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* [PATCH v10 00/11] drm/sun4i: dsi: Fixes/updates (A33 reworked!)
@ 2019-05-20  9:03 Jagan Teki
  2019-05-20  9:03 ` [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits Jagan Teki
                   ` (10 more replies)
  0 siblings, 11 replies; 54+ messages in thread
From: Jagan Teki @ 2019-05-20  9:03 UTC (permalink / raw)
  To: Maxime Ripard, David Airlie, Daniel Vetter, Chen-Yu Tsai,
	dri-devel, linux-arm-kernel, linux-kernel
  Cc: bshah, powerpan, linux-sunxi, Jagan Teki, michael, linux-amarula

Most of these issues are reproduced while supporting Allwinner A64
MIPI-DSI [1] but to confirm it with other SoC this series is reworked
on A33 since the controller tested it A33 as of now.

Since we don't have proper evidence and documentation for dsi controller
in Allwinner, these changes are more likely to rely on new working BSP
codes (even the initial driver written as per this rule).

All these fixes/updates are tested in "bananapi,s070wv20-ct16" panel
on Allwinner A33, the same panel timings are available in panel-simple
in mainline tree.

Changes for v10:
- reworked previous "Fixes/updates" patches on A33
- reworked previous A64 DSI fixes on A33
- added proper detailed commit messages with logs
- tested on BPI-M2M board.
Changes for v9:
- rebase on drm-misc
- update commit messages
- add hsync_porch overflow patch
Changes for v8:
- rebase on master
- rework on commit messages
- rework video start delay
- include drq changes from previous version
Changes for v7:
- rebase on master
- collect Merlijn Wajer Tested-by credits.
Changes for v6:
- fixed all burst mode patches as per previous version comments
- rebase on master
- update proper commit message
- dropped unneeded comments
- order the patches that make review easy
Changes for v5, v4, v3, v2:
- use existing driver code construct for hblk computation
- create separate function for vblk computation
- cleanup commit messages
- update proper commit messages
- fixed checkpatch warnings/errors
- use proper return value for tcon0 probe
- add logic to get tcon0 divider values
- simplify timings code to support burst mode
- fix drq computation return values
- rebase on master

Any inputs?
Jagan.

[1] https://patchwork.freedesktop.org/series/57834/

Jagan Teki (11):
  drm/sun4i: dsi: Fix TCON DRQ set bits
  drm/sun4i: dsi: Update start value in video start delay
  drm/sun4i: dsi: Fix video start delay computation
  drm/sun4i: tcon: Compute DCLK dividers based on format, lanes
  drm/sun4i: tcon: Export get tcon0 routine
  drm/sun4i: dsi: Probe tcon0 during dsi_bind
  drm/sun4i: dsi: Get tcon0_div at runtime
  dt-bindings: sun6i-dsi: Add VCC-DSI supply property
  drm/sun4i: sun6i_mipi_dsi: Add VCC-DSI regulator support
  [DO NOT MERGE] drm/panel: Add Bananapi S070WV20-CT16 ICN6211 MIPI-DSI to RGB bridge
  [DO NOT MERGE] ARM: dts: sun8i: bananapi-m2m: Enable Bananapi S070WV20-CT16 DSI panel

 .../bindings/display/sunxi/sun6i-dsi.txt      |   1 +
 arch/arm/boot/dts/sun8i-r16-bananapi-m2m.dts  |  40 +++
 drivers/gpu/drm/panel/Kconfig                 |   9 +
 drivers/gpu/drm/panel/Makefile                |   1 +
 .../panel/panel-bananapi-s070wv20-icn6211.c   | 293 ++++++++++++++++++
 drivers/gpu/drm/sun4i/sun4i_tcon.c            |   7 +-
 drivers/gpu/drm/sun4i/sun4i_tcon.h            |   1 +
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c        |  46 ++-
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h        |   4 +-
 9 files changed, 393 insertions(+), 9 deletions(-)
 create mode 100644 drivers/gpu/drm/panel/panel-bananapi-s070wv20-icn6211.c

-- 
2.18.0.321.gffc6fa0e3


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linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-05-20  9:03 [PATCH v10 00/11] drm/sun4i: dsi: Fixes/updates (A33 reworked!) Jagan Teki
@ 2019-05-20  9:03 ` Jagan Teki
  2019-05-23 20:34   ` Maxime Ripard
  2019-05-20  9:03 ` [PATCH v10 02/11] drm/sun4i: dsi: Update start value in video start delay Jagan Teki
                   ` (9 subsequent siblings)
  10 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-05-20  9:03 UTC (permalink / raw)
  To: Maxime Ripard, David Airlie, Daniel Vetter, Chen-Yu Tsai,
	dri-devel, linux-arm-kernel, linux-kernel
  Cc: bshah, powerpan, linux-sunxi, Jagan Teki, michael, linux-amarula

According to "DRM kernel-internal display mode structure" in
include/drm/drm_modes.h the current driver is trying to include
sync timings along with front porch value while checking and
computing drq set bits in non-burst mode.

mode->hsync_end - mode->hdisplay => horizontal front porch + sync

With adding additional sync timings, the dsi controller leads to
wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
trigger panel flip_done timed out as:

 WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
 [CRTC:46:crtc-0] vblank wait timed out
 Modules linked in:
 CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
 Hardware name: Allwinner sun8i Family
 Workqueue: events deferred_probe_work_func
 [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
 [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
 [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
 [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
 [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
 [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
 [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
 [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
 [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
 [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
 [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
 [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
 [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
 [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
 [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
 [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
 [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
 [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
 [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
 [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
 [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
 [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
 [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
 [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
 [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
 [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
 [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
 [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
 [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
 [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
 [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
 [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
 [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
 [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
 [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
 [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
 [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
 [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
 Exception stack(0xde539fb0 to 0xde539ff8)
 9fa0:                                     00000000 00000000 00000000 00000000
 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
 ---[ end trace b57eb1e5c64c6b8b ]---
 random: fast init done
 [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
 [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
 [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out

But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
non-burst DSI mode can be computed based on "horizontal front porch"
value only (no sync timings included).

Detailed evidence for drq set bits based on A33 BSP [1] [2]

=> panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
=> (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
=> tt->hor_front_porch - 20

Which is mode->hsync_start - mode->hdisplay as per
"DRM kernel-internal display mode structure" in include/drm/drm_modes.h

So, This patch update the DRQ set bits to use front porch value.

[3] https://github.com/BPI-SINOVOIP/BPI-M64-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/de_dsi.c#L774
[2] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2031
[1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L851

Tested-by: Merlijn Wajer <merlijn@wizzup.org>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index a9ed87956f6d..c5bec0096b7c 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -436,9 +436,9 @@ static void sun6i_dsi_setup_burst(struct sun6i_dsi *dsi,
 			     SUN6I_DSI_BURST_LINE_SYNC_POINT(SUN6I_DSI_SYNC_POINT));
 
 		val = SUN6I_DSI_TCON_DRQ_ENABLE_MODE;
-	} else if ((mode->hsync_end - mode->hdisplay) > 20) {
+	} else if ((mode->hsync_start - mode->hdisplay) > 20) {
 		/* Maaaaaagic */
-		u16 drq = (mode->hsync_end - mode->hdisplay) - 20;
+		u16 drq = (mode->hsync_start - mode->hdisplay) - 20;
 
 		drq *= mipi_dsi_pixel_format_to_bpp(device->format);
 		drq /= 32;
-- 
2.18.0.321.gffc6fa0e3


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* [PATCH v10 02/11] drm/sun4i: dsi: Update start value in video start delay
  2019-05-20  9:03 [PATCH v10 00/11] drm/sun4i: dsi: Fixes/updates (A33 reworked!) Jagan Teki
  2019-05-20  9:03 ` [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits Jagan Teki
@ 2019-05-20  9:03 ` Jagan Teki
  2019-05-23 20:37   ` Maxime Ripard
  2019-06-24  9:34   ` Chen-Yu Tsai
  2019-05-20  9:03 ` [PATCH v10 03/11] drm/sun4i: dsi: Fix video start delay computation Jagan Teki
                   ` (8 subsequent siblings)
  10 siblings, 2 replies; 54+ messages in thread
From: Jagan Teki @ 2019-05-20  9:03 UTC (permalink / raw)
  To: Maxime Ripard, David Airlie, Daniel Vetter, Chen-Yu Tsai,
	dri-devel, linux-arm-kernel, linux-kernel
  Cc: bshah, powerpan, linux-sunxi, Jagan Teki, michael, linux-amarula

start value in video start delay computation done in below commit
is as per the legacy bsp drivers/video/sunxi/legacy..
"drm/sun4i: dsi: Change the start delay calculation"
(sha1: da676c6aa6413d59ab0a80c97bbc273025e640b2)

This existing start delay computation gives start value of 35,
for "bananapi,s070wv20-ct16" panel timings which indeed trigger
panel flip_done timed out as:

 WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
 [CRTC:46:crtc-0] vblank wait timed out
 Modules linked in:
 CPU: 0 PID: 31 Comm: kworker/0:1 Tainted: G        W         5.1.0-next-20190514-00025-gf928bc7cc146 #15
 Hardware name: Allwinner sun8i Family
 Workqueue: events deferred_probe_work_func
 [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
 [<c010b76c>] (show_stack) from [<c0688c90>] (dump_stack+0x84/0x98)
 [<c0688c90>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
 [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
 [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
 [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
 [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
 [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
 [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
 [<c0411b64>] (restore_fbdev_mode_atomic) from [<c0411cb0>] (drm_fb_helper_pan_display+0xac/0x1d0)
 [<c0411cb0>] (drm_fb_helper_pan_display) from [<c03a4e84>] (fb_pan_display+0xcc/0x134)
 [<c03a4e84>] (fb_pan_display) from [<c03b1214>] (bit_update_start+0x14/0x30)
 [<c03b1214>] (bit_update_start) from [<c03afe94>] (fbcon_switch+0x3d8/0x4e0)
 [<c03afe94>] (fbcon_switch) from [<c03ec930>] (redraw_screen+0x174/0x238)
 [<c03ec930>] (redraw_screen) from [<c03aceb4>] (fbcon_prepare_logo+0x3c4/0x400)
 [<c03aceb4>] (fbcon_prepare_logo) from [<c03ad2b8>] (fbcon_init+0x3c8/0x5ac)
 [<c03ad2b8>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
 [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
 [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
 [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
 [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
 [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
 [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
 [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
 [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
 [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
 [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
 [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
 [<c043f060>] (sun4i_drv_bind) from [<c044b5b0>] (try_to_bring_up_master+0x164/0x1a0)
 [<c044b5b0>] (try_to_bring_up_master) from [<c044b680>] (__component_add+0x94/0x140)
 [<c044b680>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
 [<c0445e1c>] (sun6i_dsi_probe) from [<c0452f0c>] (platform_drv_probe+0x48/0x9c)
 [<c0452f0c>] (platform_drv_probe) from [<c04512e4>] (really_probe+0x1dc/0x2c8)
 [<c04512e4>] (really_probe) from [<c0451530>] (driver_probe_device+0x60/0x160)
 [<c0451530>] (driver_probe_device) from [<c044f7bc>] (bus_for_each_drv+0x74/0xb8)
 [<c044f7bc>] (bus_for_each_drv) from [<c0451094>] (__device_attach+0xd0/0x13c)
 [<c0451094>] (__device_attach) from [<c045048c>] (bus_probe_device+0x84/0x8c)
 [<c045048c>] (bus_probe_device) from [<c0450918>] (deferred_probe_work_func+0x64/0x90)
 [<c0450918>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
 [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
 [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
 [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
 Exception stack(0xde539fb0 to 0xde539ff8)
 9fa0:                                     00000000 00000000 00000000 00000000
 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
 ---[ end trace 755e10f62b83f396 ]---
 Console: switching to colour frame buffer device 100x30
 [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
 [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
 [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out

But the expected start delay value is 1 which is confirmed from
new bsp [2].

The important and unclear note on legacy and new bsp codes [1] [2]
is both use similar start computation initially but it later reassign
it to 1 in new bsp.

Unfortunately we don't have any evidence or documentation for this
reassignment to 1 in new bsp, but it is working with all supported
panels in A33, A64.

So, use the start as per new bsp code since it is working in all
the supported panels.

[2] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L807
[1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/legacy/disp/de_bsp/de/ebios/de_dsi.c#L682

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index c5bec0096b7c..b3ca85410b2c 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -364,7 +364,17 @@ static void sun6i_dsi_inst_init(struct sun6i_dsi *dsi,
 static u16 sun6i_dsi_get_video_start_delay(struct sun6i_dsi *dsi,
 					   struct drm_display_mode *mode)
 {
-	u16 start = clamp(mode->vtotal - mode->vdisplay - 10, 8, 100);
+	/**
+	 * Allwinner legacy (drivers/video/sunxi/legacy),
+	 * new (drivers/video/sunxi/disp/de/lowlevel_sun8iw5) bsp drivers
+	 * are evaluating start as:
+	 *
+	 *	vtotal - vdisplay - 10
+	 *
+	 * but the new drivers are reassigning start to 1, which seems to be
+	 * working in all supported panels as of now.
+	 */
+	u8 start = 1;
 	u16 delay = mode->vtotal - (mode->vsync_end - mode->vdisplay) + start;
 
 	if (delay > mode->vtotal)
-- 
2.18.0.321.gffc6fa0e3


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linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* [PATCH v10 03/11] drm/sun4i: dsi: Fix video start delay computation
  2019-05-20  9:03 [PATCH v10 00/11] drm/sun4i: dsi: Fixes/updates (A33 reworked!) Jagan Teki
  2019-05-20  9:03 ` [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits Jagan Teki
  2019-05-20  9:03 ` [PATCH v10 02/11] drm/sun4i: dsi: Update start value in video start delay Jagan Teki
@ 2019-05-20  9:03 ` Jagan Teki
  2019-05-23 20:38   ` Maxime Ripard
  2019-05-20  9:03 ` [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes Jagan Teki
                   ` (7 subsequent siblings)
  10 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-05-20  9:03 UTC (permalink / raw)
  To: Maxime Ripard, David Airlie, Daniel Vetter, Chen-Yu Tsai,
	dri-devel, linux-arm-kernel, linux-kernel
  Cc: bshah, powerpan, linux-sunxi, Jagan Teki, michael, linux-amarula

The current code is computing vertical video start delay as

delay = mode->vtotal - (mode->vsync_end - mode->vdisplay) + start;

On which the second parameter

mode->vsync_end - mode->vdisplay = front porch + sync timings

according to "DRM kernel-internal display mode structure" in
include/drm/drm_modes.h

With adding additional sync timings, the desired video start delay
value as 510 for "bananapi,s070wv20-ct16" panel timings which indeed
trigger panel flip_done timed out as:

 WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
 [CRTC:46:crtc-0] vblank wait timed out
 Modules linked in:
 CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00029-g09e5b0ed0a58 #18
 Hardware name: Allwinner sun8i Family
 Workqueue: events deferred_probe_work_func
 [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
 [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
 [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
 [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
 [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
 [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
 [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
 [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
 [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
 [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
 [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
 [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
 [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
 [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
 [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
 [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
 [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
 [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
 [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
 [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
 [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
 [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
 [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
 [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
 [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
 [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
 [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
 [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
 [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
 [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
 [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
 [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
 [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
 [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
 [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
 [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
 [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
 [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
 Exception stack(0xde539fb0 to 0xde539ff8)
 9fa0:                                     00000000 00000000 00000000 00000000
 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
 ---[ end trace 495200a78b24980e ]---
 random: fast init done
 [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
 [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
 [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out

But the expected video start delay value is 513 which states that
the second parameter on the computation is "front porch" value
(no sync timings included).

This is clearly confirmed from the legacy [1] and new [2] bsp codes
that the second parameter on the video start delay is "front porch"

Here is the detailed evidence for calculating front porch as per
bsp code.

vfp = panel->lcd_vt - panel->lcd_y - panel->lcd_vbp
=> (panel->lcd_vt) - panel->lcd_y - panel->lcd_vbp
=> (tt->ver_front_porch + lcdp->panel_info.lcd_vbp
    + lcdp->panel_info.lcd_y) -  panel->lcd_y - panel->lcd_vbp
=> tt->ver_front_porch

Which is mode->vsync_start - mode->vdisplay according to
"DRM kernel-internal display mode structure" in include/drm/drm_modes.h

This patch fix this by updating the video start delay to use
front porch value.

[2] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2051
[1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L803

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index b3ca85410b2c..47d571d97600 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -375,7 +375,7 @@ static u16 sun6i_dsi_get_video_start_delay(struct sun6i_dsi *dsi,
 	 * working in all supported panels as of now.
 	 */
 	u8 start = 1;
-	u16 delay = mode->vtotal - (mode->vsync_end - mode->vdisplay) + start;
+	u16 delay = mode->vtotal - (mode->vsync_start - mode->vdisplay) + start;
 
 	if (delay > mode->vtotal)
 		delay = delay % mode->vtotal;
-- 
2.18.0.321.gffc6fa0e3


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes
  2019-05-20  9:03 [PATCH v10 00/11] drm/sun4i: dsi: Fixes/updates (A33 reworked!) Jagan Teki
                   ` (2 preceding siblings ...)
  2019-05-20  9:03 ` [PATCH v10 03/11] drm/sun4i: dsi: Fix video start delay computation Jagan Teki
@ 2019-05-20  9:03 ` Jagan Teki
  2019-05-23 20:48   ` Maxime Ripard
  2019-05-20  9:03 ` [PATCH v10 05/11] drm/sun4i: tcon: Export get tcon0 routine Jagan Teki
                   ` (6 subsequent siblings)
  10 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-05-20  9:03 UTC (permalink / raw)
  To: Maxime Ripard, David Airlie, Daniel Vetter, Chen-Yu Tsai,
	dri-devel, linux-arm-kernel, linux-kernel
  Cc: bshah, powerpan, linux-sunxi, Jagan Teki, michael, linux-amarula

pll-video => pll-mipi => tcon0 => tcon0-pixel-clock is the typical
MIPI clock topology in Allwinner DSI controller.

TCON dotclock driver is computing the desired DCLK divider based on
panel pixel clock along with input DCLK min, max divider values from
tcon driver and that would eventually set the pll-mipi clock rate.

The current code is passing dsi min and max divider value as 4 via
tcon driver which would ended-up triggering below vblank wait timed out
warning on "bananapi,s070wv20-ct16" panel.

 WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
 [CRTC:46:crtc-0] vblank wait timed out
 Modules linked in:
 CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00025-g5186cdf10757-dirty #6
 Hardware name: Allwinner sun8i Family
 Workqueue: events deferred_probe_work_func
 [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
 [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
 [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
 [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
 [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
 [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
 [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
 [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
 [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
 [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
 [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
 [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
 [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
 [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
 [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
 [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
 [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
 [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
 [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
 [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
 [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
 [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
 [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
 [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
 [<c043f060>] (sun4i_drv_bind) from [<c044b588>] (try_to_bring_up_master+0x164/0x1a0)
 [<c044b588>] (try_to_bring_up_master) from [<c044b658>] (__component_add+0x94/0x140)
 [<c044b658>] (__component_add) from [<c0445e0c>] (sun6i_dsi_probe+0x144/0x234)
 [<c0445e0c>] (sun6i_dsi_probe) from [<c0452ee4>] (platform_drv_probe+0x48/0x9c)
 [<c0452ee4>] (platform_drv_probe) from [<c04512bc>] (really_probe+0x1dc/0x2c8)
 [<c04512bc>] (really_probe) from [<c0451508>] (driver_probe_device+0x60/0x160)
 [<c0451508>] (driver_probe_device) from [<c044f794>] (bus_for_each_drv+0x74/0xb8)
 [<c044f794>] (bus_for_each_drv) from [<c045106c>] (__device_attach+0xd0/0x13c)
 [<c045106c>] (__device_attach) from [<c0450464>] (bus_probe_device+0x84/0x8c)
 [<c0450464>] (bus_probe_device) from [<c04508f0>] (deferred_probe_work_func+0x64/0x90)
 [<c04508f0>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
 [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
 [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
 [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
 Exception stack(0xde539fb0 to 0xde539ff8)
 9fa0:                                     00000000 00000000 00000000 00000000
 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
 ---[ end trace 4017fea4906ab391 ]---

But accordingly to Allwinner A33, A64 BSP codes [1] [2] this divider
is clearly using 'format/lanes' for dsi divider value, dsi_clk.clk_div

Which would compute the pll_freq and set a clock rate for it in
[3] and [4] respectively.

The same issue has reproduced in A33, A64 with 4-lane and 2-lane devices
and got fixed with this computation logic 'format/lanes', so this patch
using dclk min and max dividers as per BSP.

[1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1106
[2] https://github.com/BPI-SINOVOIP/BPI-M64-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/disp_al.c#L213
[3] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1127
[4] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1161

Tested-by: Merlijn Wajer <merlijn@wizzup.org>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
 drivers/gpu/drm/sun4i/sun4i_tcon.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index 9d8d8124b1f6..8f93121fead4 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -341,8 +341,8 @@ static void sun4i_tcon0_mode_set_cpu(struct sun4i_tcon *tcon,
 	u32 block_space, start_delay;
 	u32 tcon_div;
 
-	tcon->dclk_min_div = SUN6I_DSI_TCON_DIV;
-	tcon->dclk_max_div = SUN6I_DSI_TCON_DIV;
+	tcon->dclk_min_div = bpp/lanes;
+	tcon->dclk_max_div = bpp/lanes;
 
 	sun4i_tcon0_mode_set_common(tcon, mode);
 
-- 
2.18.0.321.gffc6fa0e3


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* [PATCH v10 05/11] drm/sun4i: tcon: Export get tcon0 routine
  2019-05-20  9:03 [PATCH v10 00/11] drm/sun4i: dsi: Fixes/updates (A33 reworked!) Jagan Teki
                   ` (3 preceding siblings ...)
  2019-05-20  9:03 ` [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes Jagan Teki
@ 2019-05-20  9:03 ` Jagan Teki
  2019-05-20  9:03 ` [PATCH v10 06/11] drm/sun4i: dsi: Probe tcon0 during dsi_bind Jagan Teki
                   ` (5 subsequent siblings)
  10 siblings, 0 replies; 54+ messages in thread
From: Jagan Teki @ 2019-05-20  9:03 UTC (permalink / raw)
  To: Maxime Ripard, David Airlie, Daniel Vetter, Chen-Yu Tsai,
	dri-devel, linux-arm-kernel, linux-kernel
  Cc: bshah, powerpan, linux-sunxi, Jagan Teki, michael, linux-amarula

Sometimes tcon attributes like tcon divider, clock rate etc are needed
in interface drivers like DSI. So for such cases interface driver must
probe the respective tcon and get the attributes.

Since tcon0 probe is already available, via sun4i_get_tcon0 function,
export the same instead of probing tcon explicitly.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Merlijn Wajer <merlijn@wizzup.org>
---
 drivers/gpu/drm/sun4i/sun4i_tcon.c | 3 ++-
 drivers/gpu/drm/sun4i/sun4i_tcon.h | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index 8f93121fead4..9e9d08ee8387 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -221,7 +221,7 @@ EXPORT_SYMBOL(sun4i_tcon_enable_vblank);
  * are located in TCON0. This helper returns a pointer to TCON0's
  * sun4i_tcon structure, or NULL if not found.
  */
-static struct sun4i_tcon *sun4i_get_tcon0(struct drm_device *drm)
+struct sun4i_tcon *sun4i_get_tcon0(struct drm_device *drm)
 {
 	struct sun4i_drv *drv = drm->dev_private;
 	struct sun4i_tcon *tcon;
@@ -235,6 +235,7 @@ static struct sun4i_tcon *sun4i_get_tcon0(struct drm_device *drm)
 
 	return NULL;
 }
+EXPORT_SYMBOL(sun4i_get_tcon0);
 
 static void sun4i_tcon_set_mux(struct sun4i_tcon *tcon, int channel,
 			       const struct drm_encoder *encoder)
diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h b/drivers/gpu/drm/sun4i/sun4i_tcon.h
index 84cfb1952ff7..88e971d5f937 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.h
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h
@@ -272,6 +272,7 @@ struct sun4i_tcon {
 struct drm_bridge *sun4i_tcon_find_bridge(struct device_node *node);
 struct drm_panel *sun4i_tcon_find_panel(struct device_node *node);
 
+struct sun4i_tcon *sun4i_get_tcon0(struct drm_device *drm);
 void sun4i_tcon_enable_vblank(struct sun4i_tcon *tcon, bool enable);
 void sun4i_tcon_mode_set(struct sun4i_tcon *tcon,
 			 const struct drm_encoder *encoder,
-- 
2.18.0.321.gffc6fa0e3


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* [PATCH v10 06/11] drm/sun4i: dsi: Probe tcon0 during dsi_bind
  2019-05-20  9:03 [PATCH v10 00/11] drm/sun4i: dsi: Fixes/updates (A33 reworked!) Jagan Teki
                   ` (4 preceding siblings ...)
  2019-05-20  9:03 ` [PATCH v10 05/11] drm/sun4i: tcon: Export get tcon0 routine Jagan Teki
@ 2019-05-20  9:03 ` Jagan Teki
  2019-05-20  9:03 ` [PATCH v10 07/11] drm/sun4i: dsi: Get tcon0_div at runtime Jagan Teki
                   ` (4 subsequent siblings)
  10 siblings, 0 replies; 54+ messages in thread
From: Jagan Teki @ 2019-05-20  9:03 UTC (permalink / raw)
  To: Maxime Ripard, David Airlie, Daniel Vetter, Chen-Yu Tsai,
	dri-devel, linux-arm-kernel, linux-kernel
  Cc: bshah, powerpan, linux-sunxi, Jagan Teki, michael, linux-amarula

Probe tcon0 during dsi_bind, so-that the tcon attributes like
divider value, clock rates are available whenever it required.

Tested-by: Merlijn Wajer <merlijn@wizzup.org>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 6 ++++++
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h | 1 +
 2 files changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index 47d571d97600..1f9ed2642a47 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -1045,6 +1045,7 @@ static int sun6i_dsi_bind(struct device *dev, struct device *master,
 	struct drm_device *drm = data;
 	struct sun4i_drv *drv = drm->dev_private;
 	struct sun6i_dsi *dsi = dev_get_drvdata(dev);
+	struct sun4i_tcon *tcon0 = sun4i_get_tcon0(drm);
 	int ret;
 
 	if (!(dsi->panel || dsi->bridge)) {
@@ -1054,6 +1055,11 @@ static int sun6i_dsi_bind(struct device *dev, struct device *master,
 
 	dsi->drv = drv;
 
+	if (!tcon0)
+		return -EINVAL;
+
+	dsi->tcon = tcon0;
+
 	drm_encoder_helper_add(&dsi->encoder,
 			       &sun6i_dsi_enc_helper_funcs);
 	ret = drm_encoder_init(drm,
diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
index 9c140f55b822..f2826e3ea165 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
@@ -28,6 +28,7 @@ struct sun6i_dsi {
 
 	struct device		*dev;
 	struct sun4i_drv	*drv;
+	struct sun4i_tcon	*tcon;
 	struct mipi_dsi_device	*device;
 	struct drm_panel	*panel;
 	struct drm_bridge	*bridge;
-- 
2.18.0.321.gffc6fa0e3


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http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* [PATCH v10 07/11] drm/sun4i: dsi: Get tcon0_div at runtime
  2019-05-20  9:03 [PATCH v10 00/11] drm/sun4i: dsi: Fixes/updates (A33 reworked!) Jagan Teki
                   ` (5 preceding siblings ...)
  2019-05-20  9:03 ` [PATCH v10 06/11] drm/sun4i: dsi: Probe tcon0 during dsi_bind Jagan Teki
@ 2019-05-20  9:03 ` Jagan Teki
  2019-05-20  9:03 ` [PATCH v10 08/11] dt-bindings: sun6i-dsi: Add VCC-DSI supply property Jagan Teki
                   ` (3 subsequent siblings)
  10 siblings, 0 replies; 54+ messages in thread
From: Jagan Teki @ 2019-05-20  9:03 UTC (permalink / raw)
  To: Maxime Ripard, David Airlie, Daniel Vetter, Chen-Yu Tsai,
	dri-devel, linux-arm-kernel, linux-kernel
  Cc: bshah, powerpan, linux-sunxi, Jagan Teki, michael, linux-amarula

tcon0 divider is used while computing drq edge0 for burst mode
devices, currently driver is using default macro value 4 via
SUN6I_DSI_TCON_DIV.

Unfortunately not all the panel devices are working with this
default divider value 4, so to make future changes on this divider
value get the divider from tcon dot clock at runtime instead of
static macro value.

Tested-by: Merlijn Wajer <merlijn@wizzup.org>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 8 +++++++-
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h | 2 --
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index 1f9ed2642a47..5584e9c2f8bd 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -396,9 +396,15 @@ static u16 sun6i_dsi_get_drq_edge0(struct sun6i_dsi *dsi,
 				   struct drm_display_mode *mode,
 				   u16 line_num, u16 edge1)
 {
+	struct sun4i_tcon *tcon = dsi->tcon;
+	unsigned long dclk_rate, dclk_parent_rate, tcon0_div;
 	u16 edge0 = edge1;
 
-	edge0 += (mode->hdisplay + 40) * SUN6I_DSI_TCON_DIV / 8;
+	dclk_rate = clk_get_rate(tcon->dclk);
+	dclk_parent_rate = clk_get_rate(clk_get_parent(tcon->dclk));
+	tcon0_div = dclk_parent_rate / dclk_rate;
+
+	edge0 += (mode->hdisplay + 40) * tcon0_div / 8;
 
 	if (edge0 > line_num)
 		return edge0 - line_num;
diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
index f2826e3ea165..156523859d82 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
@@ -13,8 +13,6 @@
 #include <drm/drm_encoder.h>
 #include <drm/drm_mipi_dsi.h>
 
-#define SUN6I_DSI_TCON_DIV	4
-
 struct sun6i_dsi {
 	struct drm_connector	connector;
 	struct drm_encoder	encoder;
-- 
2.18.0.321.gffc6fa0e3


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linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* [PATCH v10 08/11] dt-bindings: sun6i-dsi: Add VCC-DSI supply property
  2019-05-20  9:03 [PATCH v10 00/11] drm/sun4i: dsi: Fixes/updates (A33 reworked!) Jagan Teki
                   ` (6 preceding siblings ...)
  2019-05-20  9:03 ` [PATCH v10 07/11] drm/sun4i: dsi: Get tcon0_div at runtime Jagan Teki
@ 2019-05-20  9:03 ` Jagan Teki
  2019-05-20  9:03 ` [PATCH v10 09/11] drm/sun4i: sun6i_mipi_dsi: Add VCC-DSI regulator support Jagan Teki
                   ` (2 subsequent siblings)
  10 siblings, 0 replies; 54+ messages in thread
From: Jagan Teki @ 2019-05-20  9:03 UTC (permalink / raw)
  To: Maxime Ripard, David Airlie, Daniel Vetter, Chen-Yu Tsai,
	dri-devel, linux-arm-kernel, linux-kernel
  Cc: bshah, powerpan, linux-sunxi, Jagan Teki, michael, linux-amarula

Allwinner MIPI DSI controllers are supplied with SoC DSI
power rails via VCC-DSI pin.

Some board still work without supplying this but give more
faith on datasheet and hardware schematics and document this
supply property in required property list.

Reviewed-by: Rob Herring <robh@kernel.org>
Tested-by: Merlijn Wajer <merlijn@wizzup.org>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
 Documentation/devicetree/bindings/display/sunxi/sun6i-dsi.txt | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/display/sunxi/sun6i-dsi.txt b/Documentation/devicetree/bindings/display/sunxi/sun6i-dsi.txt
index 6a6cf5de08b0..1cc40663b7a2 100644
--- a/Documentation/devicetree/bindings/display/sunxi/sun6i-dsi.txt
+++ b/Documentation/devicetree/bindings/display/sunxi/sun6i-dsi.txt
@@ -21,6 +21,7 @@ Required properties:
   - phys: phandle to the D-PHY
   - phy-names: must be "dphy"
   - resets: phandle to the reset controller driving the encoder
+  - vcc-dsi-supply: the VCC-DSI power supply of the DSI encoder
 
   - ports: A ports node with endpoint definitions as defined in
     Documentation/devicetree/bindings/media/video-interfaces.txt. The
-- 
2.18.0.321.gffc6fa0e3


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linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* [PATCH v10 09/11] drm/sun4i: sun6i_mipi_dsi: Add VCC-DSI regulator support
  2019-05-20  9:03 [PATCH v10 00/11] drm/sun4i: dsi: Fixes/updates (A33 reworked!) Jagan Teki
                   ` (7 preceding siblings ...)
  2019-05-20  9:03 ` [PATCH v10 08/11] dt-bindings: sun6i-dsi: Add VCC-DSI supply property Jagan Teki
@ 2019-05-20  9:03 ` Jagan Teki
  2019-06-03 13:49   ` Maxime Ripard
  2019-05-20  9:03 ` [DO NOT MERGE] [PATCH v10 10/11] drm/panel: Add Bananapi S070WV20-CT16 ICN6211 MIPI-DSI to RGB bridge Jagan Teki
  2019-05-20  9:03 ` [DO NOT MERGE] [PATCH v10 11/11] ARM: dts: sun8i: bananapi-m2m: Enable Bananapi S070WV20-CT16 DSI panel Jagan Teki
  10 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-05-20  9:03 UTC (permalink / raw)
  To: Maxime Ripard, David Airlie, Daniel Vetter, Chen-Yu Tsai,
	dri-devel, linux-arm-kernel, linux-kernel
  Cc: bshah, powerpan, linux-sunxi, Jagan Teki, michael, linux-amarula

Allwinner MIPI DSI controllers are supplied with SoC
DSI power rails via VCC-DSI pin.

Add support for this supply pin by adding voltage
regulator handling code to MIPI DSI driver.

Tested-by: Merlijn Wajer <merlijn@wizzup.org>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 14 ++++++++++++++
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h |  3 +++
 2 files changed, 17 insertions(+)

diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index 5584e9c2f8bd..a5d73a283ed7 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -1150,6 +1150,12 @@ static int sun6i_dsi_probe(struct platform_device *pdev)
 		return PTR_ERR(base);
 	}
 
+	dsi->regulator = devm_regulator_get(dev, "vcc-dsi");
+	if (IS_ERR(dsi->regulator)) {
+		dev_err(dev, "Couldn't get VCC-DSI supply\n");
+		return PTR_ERR(dsi->regulator);
+	}
+
 	dsi->regs = devm_regmap_init_mmio_clk(dev, "bus", base,
 					      &sun6i_dsi_regmap_config);
 	if (IS_ERR(dsi->regs)) {
@@ -1223,6 +1229,13 @@ static int sun6i_dsi_remove(struct platform_device *pdev)
 static int __maybe_unused sun6i_dsi_runtime_resume(struct device *dev)
 {
 	struct sun6i_dsi *dsi = dev_get_drvdata(dev);
+	int err;
+
+	err = regulator_enable(dsi->regulator);
+	if (err) {
+		dev_err(dsi->dev, "failed to enable VCC-DSI supply: %d\n", err);
+		return err;
+	}
 
 	reset_control_deassert(dsi->reset);
 	clk_prepare_enable(dsi->mod_clk);
@@ -1255,6 +1268,7 @@ static int __maybe_unused sun6i_dsi_runtime_suspend(struct device *dev)
 
 	clk_disable_unprepare(dsi->mod_clk);
 	reset_control_assert(dsi->reset);
+	regulator_disable(dsi->regulator);
 
 	return 0;
 }
diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
index 156523859d82..c76b71259d2e 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
@@ -13,6 +13,8 @@
 #include <drm/drm_encoder.h>
 #include <drm/drm_mipi_dsi.h>
 
+#include <linux/regulator/consumer.h>
+
 struct sun6i_dsi {
 	struct drm_connector	connector;
 	struct drm_encoder	encoder;
@@ -21,6 +23,7 @@ struct sun6i_dsi {
 	struct clk		*bus_clk;
 	struct clk		*mod_clk;
 	struct regmap		*regs;
+	struct regulator	*regulator;
 	struct reset_control	*reset;
 	struct phy		*dphy;
 
-- 
2.18.0.321.gffc6fa0e3


_______________________________________________
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linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* [DO NOT MERGE] [PATCH v10 10/11] drm/panel: Add Bananapi S070WV20-CT16 ICN6211 MIPI-DSI to RGB bridge
  2019-05-20  9:03 [PATCH v10 00/11] drm/sun4i: dsi: Fixes/updates (A33 reworked!) Jagan Teki
                   ` (8 preceding siblings ...)
  2019-05-20  9:03 ` [PATCH v10 09/11] drm/sun4i: sun6i_mipi_dsi: Add VCC-DSI regulator support Jagan Teki
@ 2019-05-20  9:03 ` Jagan Teki
  2019-05-20  9:03 ` [DO NOT MERGE] [PATCH v10 11/11] ARM: dts: sun8i: bananapi-m2m: Enable Bananapi S070WV20-CT16 DSI panel Jagan Teki
  10 siblings, 0 replies; 54+ messages in thread
From: Jagan Teki @ 2019-05-20  9:03 UTC (permalink / raw)
  To: Maxime Ripard, David Airlie, Daniel Vetter, Chen-Yu Tsai,
	dri-devel, linux-arm-kernel, linux-kernel
  Cc: bshah, powerpan, linux-sunxi, Jagan Teki, michael, linux-amarula

Bananapi S070WV20-CT16 ICN6211 is 800x480, 4-lane MIPI-DSI to RGB bridge
panel which can be used to connect via DSI port on BPI-M64 board,
so add a driver for it.

The same panel PCB comes with parallel RBG which is supported via
panel-simple driver with "bananapi,s070wv20-ct16" compatible.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
 drivers/gpu/drm/panel/Kconfig                 |   9 +
 drivers/gpu/drm/panel/Makefile                |   1 +
 .../panel/panel-bananapi-s070wv20-icn6211.c   | 293 ++++++++++++++++++
 3 files changed, 303 insertions(+)
 create mode 100644 drivers/gpu/drm/panel/panel-bananapi-s070wv20-icn6211.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index e36dbb4df867..d0cb2fa3e721 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -17,6 +17,15 @@ config DRM_PANEL_ARM_VERSATILE
 	  reference designs. The panel is detected using special registers
 	  in the Versatile family syscon registers.
 
+config DRM_PANEL_BANANAPI_S070WV20_ICN6211
+	tristate "Bananapi S070WV20-CT16 ICN6211 MIPI-DSI to RGB bridge panel driver"
+	depends on OF
+	depends on DRM_MIPI_DSI
+	depends on BACKLIGHT_CLASS_DEVICE
+	help
+	  Say Y if you want to enable support for panels based on the
+	  Bananapi S070WV20-CT16 MIPI-DSI controller.
+
 config DRM_PANEL_LVDS
 	tristate "Generic LVDS panel driver"
 	depends on OF
diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index 78e3dc376bdd..a68e990a4a73 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_DRM_PANEL_ARM_VERSATILE) += panel-arm-versatile.o
+obj-$(CONFIG_DRM_PANEL_BANANAPI_S070WV20_ICN6211) += panel-bananapi-s070wv20-icn6211.o
 obj-$(CONFIG_DRM_PANEL_LVDS) += panel-lvds.o
 obj-$(CONFIG_DRM_PANEL_SIMPLE) += panel-simple.o
 obj-$(CONFIG_DRM_PANEL_FEIYANG_FY07024DI26A30D) += panel-feiyang-fy07024di26a30d.o
diff --git a/drivers/gpu/drm/panel/panel-bananapi-s070wv20-icn6211.c b/drivers/gpu/drm/panel/panel-bananapi-s070wv20-icn6211.c
new file mode 100644
index 000000000000..52a5b60278af
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-bananapi-s070wv20-icn6211.c
@@ -0,0 +1,293 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018 Amarula Solutions
+ * Author: Jagan Teki <jagan@amarulasolutions.com>
+ */
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+
+#include <linux/gpio/consumer.h>
+#include <linux/regulator/consumer.h>
+
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_panel.h>
+
+struct s070wv20 {
+	struct drm_panel	panel;
+	struct mipi_dsi_device	*dsi;
+
+	struct backlight_device	*backlight;
+	struct regulator	*vdd;
+	struct gpio_desc	*enable_gpio;
+	struct gpio_desc	*reset_gpio;
+};
+
+static inline struct s070wv20 *panel_to_s070wv20(struct drm_panel *panel)
+{
+	return container_of(panel, struct s070wv20, panel);
+}
+
+struct s070wv20_init_cmd {
+	size_t len;
+	const char *data;
+};
+
+#define S070WV20_INIT_CMD(...) { \
+	.len = sizeof((char[]){__VA_ARGS__}), \
+	.data = (char[]){__VA_ARGS__} }
+
+static const struct s070wv20_init_cmd s070wv20_init_cmds[] = {
+	S070WV20_INIT_CMD(0x7A, 0xC1),
+	S070WV20_INIT_CMD(0x20, 0x20),
+	S070WV20_INIT_CMD(0x21, 0xE0),
+	S070WV20_INIT_CMD(0x22, 0x13),
+	S070WV20_INIT_CMD(0x23, 0x28),
+	S070WV20_INIT_CMD(0x24, 0x30),
+	S070WV20_INIT_CMD(0x25, 0x28),
+	S070WV20_INIT_CMD(0x26, 0x00),
+	S070WV20_INIT_CMD(0x27, 0x0D),
+	S070WV20_INIT_CMD(0x28, 0x03),
+	S070WV20_INIT_CMD(0x29, 0x1D),
+	S070WV20_INIT_CMD(0x34, 0x80),
+	S070WV20_INIT_CMD(0x36, 0x28),
+	S070WV20_INIT_CMD(0xB5, 0xA0),
+	S070WV20_INIT_CMD(0x5C, 0xFF),
+	S070WV20_INIT_CMD(0x2A, 0x01),
+	S070WV20_INIT_CMD(0x56, 0x92),
+	S070WV20_INIT_CMD(0x6B, 0x71),
+	S070WV20_INIT_CMD(0x69, 0x2B),
+	S070WV20_INIT_CMD(0x10, 0x40),
+	S070WV20_INIT_CMD(0x11, 0x98),
+	S070WV20_INIT_CMD(0xB6, 0x20),
+	S070WV20_INIT_CMD(0x51, 0x20),
+	S070WV20_INIT_CMD(0x09, 0x10),
+};
+
+static int s070wv20_prepare(struct drm_panel *panel)
+{
+	struct s070wv20 *ctx = panel_to_s070wv20(panel);
+	struct mipi_dsi_device *dsi = ctx->dsi;
+	unsigned int i;
+	int ret;
+
+	ret = regulator_enable(ctx->vdd);
+	if (ret)
+		return ret;
+
+	msleep(50);
+
+	gpiod_set_value(ctx->reset_gpio, 1);
+	msleep(50);
+
+	gpiod_set_value(ctx->enable_gpio, 1);
+	msleep(50);
+
+	gpiod_set_value(ctx->reset_gpio, 0);
+	msleep(50);
+
+	gpiod_set_value(ctx->reset_gpio, 1);
+	msleep(20);
+
+	for (i = 0; i < ARRAY_SIZE(s070wv20_init_cmds); i++) {
+		const struct s070wv20_init_cmd *cmd = &s070wv20_init_cmds[i];
+
+		ret = mipi_dsi_generic_write(dsi, cmd->data, cmd->len);
+		if (ret < 0)
+			return ret;
+
+		msleep(10);
+	}
+
+	return 0;
+}
+
+static int s070wv20_enable(struct drm_panel *panel)
+{
+	struct s070wv20 *ctx = panel_to_s070wv20(panel);
+
+	msleep(120);
+
+	mipi_dsi_dcs_set_display_on(ctx->dsi);
+	backlight_enable(ctx->backlight);
+
+	return 0;
+}
+
+static int s070wv20_disable(struct drm_panel *panel)
+{
+	struct s070wv20 *ctx = panel_to_s070wv20(panel);
+
+	backlight_disable(ctx->backlight);
+	return mipi_dsi_dcs_set_display_on(ctx->dsi);
+}
+
+static int s070wv20_unprepare(struct drm_panel *panel)
+{
+	struct s070wv20 *ctx = panel_to_s070wv20(panel);
+	int ret;
+
+	ret = mipi_dsi_dcs_set_display_off(ctx->dsi);
+	if (ret < 0)
+		dev_err(panel->dev, "failed to set display off: %d\n", ret);
+
+	ret = mipi_dsi_dcs_enter_sleep_mode(ctx->dsi);
+	if (ret < 0)
+		dev_err(panel->dev, "failed to enter sleep mode: %d\n", ret);
+
+	msleep(100);
+
+	gpiod_set_value(ctx->reset_gpio, 0);
+
+	gpiod_set_value(ctx->reset_gpio, 1);
+
+	gpiod_set_value(ctx->enable_gpio, 0);
+
+	gpiod_set_value(ctx->reset_gpio, 0);
+
+	regulator_disable(ctx->vdd);
+
+	return 0;
+}
+
+static const struct drm_display_mode s070wv20_default_mode = {
+	.clock = 30000,
+	.vrefresh = 60,
+
+	.hdisplay = 800,
+	.hsync_start = 800 + 40,
+	.hsync_end = 800 + 40 + 48,
+	.htotal = 800 + 40 + 48 + 40,
+
+	.vdisplay = 480,
+	.vsync_start = 480 + 13,
+	.vsync_end = 480 + 13 + 3,
+	.vtotal = 480 + 13 + 3 + 29,
+
+	.width_mm	= 86,
+	.height_mm	= 154,
+};
+
+static int s070wv20_get_modes(struct drm_panel *panel)
+{
+	struct drm_connector *connector = panel->connector;
+	struct s070wv20 *ctx = panel_to_s070wv20(panel);
+	struct drm_display_mode *mode;
+
+	mode = drm_mode_duplicate(panel->drm, &s070wv20_default_mode);
+	if (!mode) {
+		dev_err(&ctx->dsi->dev, "failed to add mode %ux%ux@%u\n",
+			s070wv20_default_mode.hdisplay,
+			s070wv20_default_mode.vdisplay,
+			s070wv20_default_mode.vrefresh);
+		return -ENOMEM;
+	}
+
+	drm_mode_set_name(mode);
+
+	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
+	drm_mode_probed_add(connector, mode);
+
+	panel->connector->display_info.width_mm = mode->width_mm;
+	panel->connector->display_info.height_mm = mode->height_mm;
+
+	return 1;
+}
+
+static const struct drm_panel_funcs s070wv20_funcs = {
+	.disable = s070wv20_disable,
+	.unprepare = s070wv20_unprepare,
+	.prepare = s070wv20_prepare,
+	.enable = s070wv20_enable,
+	.get_modes = s070wv20_get_modes,
+};
+
+static int s070wv20_dsi_probe(struct mipi_dsi_device *dsi)
+{
+	struct device_node *np;
+	struct s070wv20 *ctx;
+	int ret;
+
+	ctx = devm_kzalloc(&dsi->dev, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+	mipi_dsi_set_drvdata(dsi, ctx);
+	ctx->dsi = dsi;
+
+	drm_panel_init(&ctx->panel);
+	ctx->panel.dev = &dsi->dev;
+	ctx->panel.funcs = &s070wv20_funcs;
+
+	ctx->vdd = devm_regulator_get(&dsi->dev, "vdd");
+	if (IS_ERR(ctx->vdd)) {
+		dev_err(&dsi->dev, "Couldn't get vdd regulator\n");
+		return PTR_ERR(ctx->vdd);
+	}
+
+	ctx->enable_gpio = devm_gpiod_get(&dsi->dev, "enable", GPIOD_OUT_LOW);
+	if (IS_ERR(ctx->enable_gpio)) {
+		dev_err(&dsi->dev, "Couldn't get our enable GPIO\n");
+		return PTR_ERR(ctx->enable_gpio);
+	}
+
+	ctx->reset_gpio = devm_gpiod_get(&dsi->dev, "reset", GPIOD_OUT_LOW);
+	if (IS_ERR(ctx->reset_gpio)) {
+		dev_err(&dsi->dev, "Couldn't get our reset GPIO\n");
+		return PTR_ERR(ctx->reset_gpio);
+	}
+
+	np = of_parse_phandle(dsi->dev.of_node, "backlight", 0);
+	if (np) {
+		ctx->backlight = of_find_backlight_by_node(np);
+		of_node_put(np);
+
+		if (!ctx->backlight)
+			return -EPROBE_DEFER;
+	}
+
+	ret = drm_panel_add(&ctx->panel);
+	if (ret < 0)
+		return ret;
+
+	dsi->mode_flags = MIPI_DSI_MODE_VIDEO_SYNC_PULSE;
+	dsi->format = MIPI_DSI_FMT_RGB888;
+	dsi->lanes = 4;
+
+	return mipi_dsi_attach(dsi);
+}
+
+static int s070wv20_dsi_remove(struct mipi_dsi_device *dsi)
+{
+	struct s070wv20 *ctx = mipi_dsi_get_drvdata(dsi);
+
+	mipi_dsi_detach(dsi);
+	drm_panel_remove(&ctx->panel);
+
+	if (ctx->backlight)
+		put_device(&ctx->backlight->dev);
+
+	return 0;
+}
+
+static const struct of_device_id s070wv20_of_match[] = {
+	{ .compatible = "bananapi,s070wv20-ct16-icn6211", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, s070wv20_of_match);
+
+static struct mipi_dsi_driver s070wv20_driver = {
+	.probe = s070wv20_dsi_probe,
+	.remove = s070wv20_dsi_remove,
+	.driver = {
+		.name = "bananapi-s070wv20-ct16-icn6211",
+		.of_match_table = s070wv20_of_match,
+	},
+};
+module_mipi_dsi_driver(s070wv20_driver);
+
+MODULE_AUTHOR("Jagan Teki <jagan@amarulasolutions.com>");
+MODULE_DESCRIPTION("Bananapi S070WV20-CT16 ICN6211 MIPI-DSI to RGB");
+MODULE_LICENSE("GPL v2");
-- 
2.18.0.321.gffc6fa0e3


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^ permalink raw reply	[flat|nested] 54+ messages in thread

* [DO NOT MERGE] [PATCH v10 11/11] ARM: dts: sun8i: bananapi-m2m: Enable Bananapi S070WV20-CT16 DSI panel
  2019-05-20  9:03 [PATCH v10 00/11] drm/sun4i: dsi: Fixes/updates (A33 reworked!) Jagan Teki
                   ` (9 preceding siblings ...)
  2019-05-20  9:03 ` [DO NOT MERGE] [PATCH v10 10/11] drm/panel: Add Bananapi S070WV20-CT16 ICN6211 MIPI-DSI to RGB bridge Jagan Teki
@ 2019-05-20  9:03 ` Jagan Teki
  10 siblings, 0 replies; 54+ messages in thread
From: Jagan Teki @ 2019-05-20  9:03 UTC (permalink / raw)
  To: Maxime Ripard, David Airlie, Daniel Vetter, Chen-Yu Tsai,
	dri-devel, linux-arm-kernel, linux-kernel
  Cc: bshah, powerpan, linux-sunxi, Jagan Teki, michael, linux-amarula

This patch add support for Bananapi S070WV20-CT16 DSI panel to
BPI-M2M board.

DSI panel connected via board DSI port with,
- DCDC1 as VCC-DSI supply
- DLDO1 as VDD supply
- PL5 gpio for lcd reset gpio pin
- PB7 gpio for lcd enable gpio pin
- PL4 gpio for backlight enable pin

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
 arch/arm/boot/dts/sun8i-r16-bananapi-m2m.dts | 40 ++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/arch/arm/boot/dts/sun8i-r16-bananapi-m2m.dts b/arch/arm/boot/dts/sun8i-r16-bananapi-m2m.dts
index e1c75f7fa3ca..4e71e81d2bad 100644
--- a/arch/arm/boot/dts/sun8i-r16-bananapi-m2m.dts
+++ b/arch/arm/boot/dts/sun8i-r16-bananapi-m2m.dts
@@ -44,6 +44,7 @@
 #include "sun8i-a33.dtsi"
 
 #include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/pwm/pwm.h>
 
 / {
 	model = "BananaPi M2 Magic";
@@ -61,6 +62,14 @@
 		stdout-path = "serial0:115200n8";
 	};
 
+	backlight: backlight {
+		compatible = "pwm-backlight";
+		pwms = <&pwm 0 50000 PWM_POLARITY_INVERTED>;
+		brightness-levels = <1 2 4 8 16 32 64 128 255>;
+		default-brightness-level = <8>;
+		enable-gpios = <&r_pio 0 4 GPIO_ACTIVE_HIGH>; /* LCD-BL-EN: PL4 */
+	};
+
 	leds {
 		compatible = "gpio-leds";
 
@@ -122,6 +131,27 @@
 	status = "okay";
 };
 
+&de {
+	status = "okay";
+};
+
+&dphy {
+	status = "okay";
+};
+
+&dsi {
+	vcc-dsi-supply = <&reg_dcdc1>;		/* VCC3V3-DSI */
+	status = "okay";
+
+	panel@0 {
+		compatible = "bananapi,s070wv20-ct16-icn6211";
+		reg = <0>;
+		enable-gpios = <&pio 1 7 GPIO_ACTIVE_HIGH>; /* LCD-PWR-EN: PB7 */
+		reset-gpios = <&r_pio 0 5 GPIO_ACTIVE_HIGH>; /* LCD-RST: PL5 */
+		backlight = <&backlight>;
+	};
+};
+
 &ehci0 {
 	status = "okay";
 };
@@ -157,6 +187,12 @@
 	status = "okay";
 };
 
+&pwm {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pwm0_pin>;
+	status = "okay";
+};
+
 &r_rsb {
 	status = "okay";
 
@@ -269,6 +305,10 @@
 	status = "okay";
 };
 
+&tcon0 {
+	status = "okay";
+};
+
 &uart0 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&uart0_pb_pins>;
-- 
2.18.0.321.gffc6fa0e3


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http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-05-20  9:03 ` [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits Jagan Teki
@ 2019-05-23 20:34   ` Maxime Ripard
  2019-05-24 10:18     ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-05-23 20:34 UTC (permalink / raw)
  To: Jagan Teki
  Cc: bshah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	powerpan, Chen-Yu Tsai, Daniel Vetter, michael, linux-amarula,
	linux-arm-kernel

On Mon, May 20, 2019 at 02:33:08PM +0530, Jagan Teki wrote:
> According to "DRM kernel-internal display mode structure" in
> include/drm/drm_modes.h the current driver is trying to include
> sync timings along with front porch value while checking and
> computing drq set bits in non-burst mode.
>
> mode->hsync_end - mode->hdisplay => horizontal front porch + sync
>
> With adding additional sync timings, the dsi controller leads to
> wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> trigger panel flip_done timed out as:
>
>  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
>  [CRTC:46:crtc-0] vblank wait timed out
>  Modules linked in:
>  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
>  Hardware name: Allwinner sun8i Family
>  Workqueue: events deferred_probe_work_func
>  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
>  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
>  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
>  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
>  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
>  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
>  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
>  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
>  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
>  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
>  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
>  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
>  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
>  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
>  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
>  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
>  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
>  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
>  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
>  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
>  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
>  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
>  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
>  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
>  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
>  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
>  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
>  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
>  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
>  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
>  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
>  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
>  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
>  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
>  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
>  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
>  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
>  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
>  Exception stack(0xde539fb0 to 0xde539ff8)
>  9fa0:                                     00000000 00000000 00000000 00000000
>  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
>  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
>  ---[ end trace b57eb1e5c64c6b8b ]---
>  random: fast init done
>  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
>  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
>  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
>
> But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> non-burst DSI mode can be computed based on "horizontal front porch"
> value only (no sync timings included).
>
> Detailed evidence for drq set bits based on A33 BSP [1] [2]
>
> => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> => tt->hor_front_porch - 20

The thing is, while your explanation on the DRM side is sound,
Allwinner has been using the hbp field of their panel description to
store what DRM calls the backporch and the sync period.

And nowhere in that commit log you are describing whether it's still
an issue or not, and if it's not anymore how you did test that it's
not the case anymore.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 02/11] drm/sun4i: dsi: Update start value in video start delay
  2019-05-20  9:03 ` [PATCH v10 02/11] drm/sun4i: dsi: Update start value in video start delay Jagan Teki
@ 2019-05-23 20:37   ` Maxime Ripard
  2019-05-24 10:25     ` Jagan Teki
  2019-06-24  9:34   ` Chen-Yu Tsai
  1 sibling, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-05-23 20:37 UTC (permalink / raw)
  To: Jagan Teki
  Cc: bshah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	powerpan, Chen-Yu Tsai, Daniel Vetter, michael, linux-amarula,
	linux-arm-kernel

On Mon, May 20, 2019 at 02:33:09PM +0530, Jagan Teki wrote:
> start value in video start delay computation done in below commit
> is as per the legacy bsp drivers/video/sunxi/legacy..
> "drm/sun4i: dsi: Change the start delay calculation"
> (sha1: da676c6aa6413d59ab0a80c97bbc273025e640b2)
>
> This existing start delay computation gives start value of 35,
> for "bananapi,s070wv20-ct16" panel timings which indeed trigger
> panel flip_done timed out as:
>
>  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
>  [CRTC:46:crtc-0] vblank wait timed out
>  Modules linked in:
>  CPU: 0 PID: 31 Comm: kworker/0:1 Tainted: G        W         5.1.0-next-20190514-00025-gf928bc7cc146 #15
>  Hardware name: Allwinner sun8i Family
>  Workqueue: events deferred_probe_work_func
>  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
>  [<c010b76c>] (show_stack) from [<c0688c90>] (dump_stack+0x84/0x98)
>  [<c0688c90>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
>  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
>  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
>  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
>  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
>  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
>  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
>  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c0411cb0>] (drm_fb_helper_pan_display+0xac/0x1d0)
>  [<c0411cb0>] (drm_fb_helper_pan_display) from [<c03a4e84>] (fb_pan_display+0xcc/0x134)
>  [<c03a4e84>] (fb_pan_display) from [<c03b1214>] (bit_update_start+0x14/0x30)
>  [<c03b1214>] (bit_update_start) from [<c03afe94>] (fbcon_switch+0x3d8/0x4e0)
>  [<c03afe94>] (fbcon_switch) from [<c03ec930>] (redraw_screen+0x174/0x238)
>  [<c03ec930>] (redraw_screen) from [<c03aceb4>] (fbcon_prepare_logo+0x3c4/0x400)
>  [<c03aceb4>] (fbcon_prepare_logo) from [<c03ad2b8>] (fbcon_init+0x3c8/0x5ac)
>  [<c03ad2b8>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
>  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
>  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
>  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
>  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
>  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
>  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
>  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
>  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
>  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
>  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
>  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
>  [<c043f060>] (sun4i_drv_bind) from [<c044b5b0>] (try_to_bring_up_master+0x164/0x1a0)
>  [<c044b5b0>] (try_to_bring_up_master) from [<c044b680>] (__component_add+0x94/0x140)
>  [<c044b680>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
>  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452f0c>] (platform_drv_probe+0x48/0x9c)
>  [<c0452f0c>] (platform_drv_probe) from [<c04512e4>] (really_probe+0x1dc/0x2c8)
>  [<c04512e4>] (really_probe) from [<c0451530>] (driver_probe_device+0x60/0x160)
>  [<c0451530>] (driver_probe_device) from [<c044f7bc>] (bus_for_each_drv+0x74/0xb8)
>  [<c044f7bc>] (bus_for_each_drv) from [<c0451094>] (__device_attach+0xd0/0x13c)
>  [<c0451094>] (__device_attach) from [<c045048c>] (bus_probe_device+0x84/0x8c)
>  [<c045048c>] (bus_probe_device) from [<c0450918>] (deferred_probe_work_func+0x64/0x90)
>  [<c0450918>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
>  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
>  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
>  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
>  Exception stack(0xde539fb0 to 0xde539ff8)
>  9fa0:                                     00000000 00000000 00000000 00000000
>  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
>  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
>  ---[ end trace 755e10f62b83f396 ]---
>  Console: switching to colour frame buffer device 100x30
>  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
>  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
>  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
>
> But the expected start delay value is 1 which is confirmed from
> new bsp [2].

If you're saying that the "legacy" link (second one) is the new BSP.

> The important and unclear note on legacy and new bsp codes [1] [2]
> is both use similar start computation initially but it later reassign
> it to 1 in new bsp.

Then start_delay is never reassigned to 1 in that link, and is clamped
between 8 and 100 as the code that you are removing is doing.

> Unfortunately we don't have any evidence or documentation for this
> reassignment to 1 in new bsp, but it is working with all supported
> panels in A33, A64.

No, it's not. That was added to fix a panel that is supported today.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 03/11] drm/sun4i: dsi: Fix video start delay computation
  2019-05-20  9:03 ` [PATCH v10 03/11] drm/sun4i: dsi: Fix video start delay computation Jagan Teki
@ 2019-05-23 20:38   ` Maxime Ripard
  2019-05-24 10:26     ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-05-23 20:38 UTC (permalink / raw)
  To: Jagan Teki
  Cc: bshah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	powerpan, Chen-Yu Tsai, Daniel Vetter, michael, linux-amarula,
	linux-arm-kernel

On Mon, May 20, 2019 at 02:33:10PM +0530, Jagan Teki wrote:
> The current code is computing vertical video start delay as
>
> delay = mode->vtotal - (mode->vsync_end - mode->vdisplay) + start;
>
> On which the second parameter
>
> mode->vsync_end - mode->vdisplay = front porch + sync timings
>
> according to "DRM kernel-internal display mode structure" in
> include/drm/drm_modes.h
>
> With adding additional sync timings, the desired video start delay
> value as 510 for "bananapi,s070wv20-ct16" panel timings which indeed
> trigger panel flip_done timed out as:
>
>  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
>  [CRTC:46:crtc-0] vblank wait timed out
>  Modules linked in:
>  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00029-g09e5b0ed0a58 #18
>  Hardware name: Allwinner sun8i Family
>  Workqueue: events deferred_probe_work_func
>  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
>  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
>  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
>  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
>  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
>  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
>  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
>  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
>  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
>  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
>  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
>  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
>  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
>  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
>  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
>  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
>  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
>  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
>  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
>  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
>  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
>  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
>  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
>  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
>  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
>  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
>  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
>  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
>  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
>  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
>  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
>  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
>  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
>  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
>  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
>  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
>  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
>  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
>  Exception stack(0xde539fb0 to 0xde539ff8)
>  9fa0:                                     00000000 00000000 00000000 00000000
>  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
>  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
>  ---[ end trace 495200a78b24980e ]---
>  random: fast init done
>  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
>  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
>  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
>
> But the expected video start delay value is 513 which states that
> the second parameter on the computation is "front porch" value
> (no sync timings included).
>
> This is clearly confirmed from the legacy [1] and new [2] bsp codes
> that the second parameter on the video start delay is "front porch"
>
> Here is the detailed evidence for calculating front porch as per
> bsp code.
>
> vfp = panel->lcd_vt - panel->lcd_y - panel->lcd_vbp
> => (panel->lcd_vt) - panel->lcd_y - panel->lcd_vbp
> => (tt->ver_front_porch + lcdp->panel_info.lcd_vbp
>     + lcdp->panel_info.lcd_y) -  panel->lcd_y - panel->lcd_vbp
> => tt->ver_front_porch

The comment on patch 1 still applies on this patch

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes
  2019-05-20  9:03 ` [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes Jagan Teki
@ 2019-05-23 20:48   ` Maxime Ripard
  2019-05-24 10:07     ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-05-23 20:48 UTC (permalink / raw)
  To: Jagan Teki
  Cc: bshah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	powerpan, Chen-Yu Tsai, Daniel Vetter, michael, linux-amarula,
	linux-arm-kernel

On Mon, May 20, 2019 at 02:33:11PM +0530, Jagan Teki wrote:
> pll-video => pll-mipi => tcon0 => tcon0-pixel-clock is the typical
> MIPI clock topology in Allwinner DSI controller.
>
> TCON dotclock driver is computing the desired DCLK divider based on
> panel pixel clock along with input DCLK min, max divider values from
> tcon driver and that would eventually set the pll-mipi clock rate.
>
> The current code is passing dsi min and max divider value as 4 via
> tcon driver which would ended-up triggering below vblank wait timed out
> warning on "bananapi,s070wv20-ct16" panel.
>
>  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
>  [CRTC:46:crtc-0] vblank wait timed out
>  Modules linked in:
>  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00025-g5186cdf10757-dirty #6
>  Hardware name: Allwinner sun8i Family
>  Workqueue: events deferred_probe_work_func
>  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
>  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
>  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
>  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
>  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
>  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
>  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
>  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
>  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
>  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
>  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
>  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
>  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
>  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
>  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
>  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
>  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
>  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
>  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
>  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
>  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
>  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
>  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
>  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
>  [<c043f060>] (sun4i_drv_bind) from [<c044b588>] (try_to_bring_up_master+0x164/0x1a0)
>  [<c044b588>] (try_to_bring_up_master) from [<c044b658>] (__component_add+0x94/0x140)
>  [<c044b658>] (__component_add) from [<c0445e0c>] (sun6i_dsi_probe+0x144/0x234)
>  [<c0445e0c>] (sun6i_dsi_probe) from [<c0452ee4>] (platform_drv_probe+0x48/0x9c)
>  [<c0452ee4>] (platform_drv_probe) from [<c04512bc>] (really_probe+0x1dc/0x2c8)
>  [<c04512bc>] (really_probe) from [<c0451508>] (driver_probe_device+0x60/0x160)
>  [<c0451508>] (driver_probe_device) from [<c044f794>] (bus_for_each_drv+0x74/0xb8)
>  [<c044f794>] (bus_for_each_drv) from [<c045106c>] (__device_attach+0xd0/0x13c)
>  [<c045106c>] (__device_attach) from [<c0450464>] (bus_probe_device+0x84/0x8c)
>  [<c0450464>] (bus_probe_device) from [<c04508f0>] (deferred_probe_work_func+0x64/0x90)
>  [<c04508f0>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
>  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
>  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
>  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
>  Exception stack(0xde539fb0 to 0xde539ff8)
>  9fa0:                                     00000000 00000000 00000000 00000000
>  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
>  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
>  ---[ end trace 4017fea4906ab391 ]---
>
> But accordingly to Allwinner A33, A64 BSP codes [1] [2] this divider
> is clearly using 'format/lanes' for dsi divider value, dsi_clk.clk_div
>
> Which would compute the pll_freq and set a clock rate for it in
> [3] and [4] respectively.
>
> The same issue has reproduced in A33, A64 with 4-lane and 2-lane devices
> and got fixed with this computation logic 'format/lanes', so this patch
> using dclk min and max dividers as per BSP.
>
> [1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1106
> [2] https://github.com/BPI-SINOVOIP/BPI-M64-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/disp_al.c#L213
> [3] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1127
> [4] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1161

In that mail, I've pointed out that clk_div isn't used for the TCON dclk divider:
http://lists.infradead.org/pipermail/linux-arm-kernel/2019-February/629596.html

The only reply you've sent is that you indeed see that the divider is
set to 4 in the BSP, but you're now saying that the BSP can change
it. If so, then please point exactly the flaw in the explanation in
that mail.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes
  2019-05-23 20:48   ` Maxime Ripard
@ 2019-05-24 10:07     ` Jagan Teki
  2019-06-04 14:30       ` Maxime Ripard
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-05-24 10:07 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Fri, May 24, 2019 at 2:18 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Mon, May 20, 2019 at 02:33:11PM +0530, Jagan Teki wrote:
> > pll-video => pll-mipi => tcon0 => tcon0-pixel-clock is the typical
> > MIPI clock topology in Allwinner DSI controller.
> >
> > TCON dotclock driver is computing the desired DCLK divider based on
> > panel pixel clock along with input DCLK min, max divider values from
> > tcon driver and that would eventually set the pll-mipi clock rate.
> >
> > The current code is passing dsi min and max divider value as 4 via
> > tcon driver which would ended-up triggering below vblank wait timed out
> > warning on "bananapi,s070wv20-ct16" panel.
> >
> >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> >  [CRTC:46:crtc-0] vblank wait timed out
> >  Modules linked in:
> >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00025-g5186cdf10757-dirty #6
> >  Hardware name: Allwinner sun8i Family
> >  Workqueue: events deferred_probe_work_func
> >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> >  [<c043f060>] (sun4i_drv_bind) from [<c044b588>] (try_to_bring_up_master+0x164/0x1a0)
> >  [<c044b588>] (try_to_bring_up_master) from [<c044b658>] (__component_add+0x94/0x140)
> >  [<c044b658>] (__component_add) from [<c0445e0c>] (sun6i_dsi_probe+0x144/0x234)
> >  [<c0445e0c>] (sun6i_dsi_probe) from [<c0452ee4>] (platform_drv_probe+0x48/0x9c)
> >  [<c0452ee4>] (platform_drv_probe) from [<c04512bc>] (really_probe+0x1dc/0x2c8)
> >  [<c04512bc>] (really_probe) from [<c0451508>] (driver_probe_device+0x60/0x160)
> >  [<c0451508>] (driver_probe_device) from [<c044f794>] (bus_for_each_drv+0x74/0xb8)
> >  [<c044f794>] (bus_for_each_drv) from [<c045106c>] (__device_attach+0xd0/0x13c)
> >  [<c045106c>] (__device_attach) from [<c0450464>] (bus_probe_device+0x84/0x8c)
> >  [<c0450464>] (bus_probe_device) from [<c04508f0>] (deferred_probe_work_func+0x64/0x90)
> >  [<c04508f0>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> >  Exception stack(0xde539fb0 to 0xde539ff8)
> >  9fa0:                                     00000000 00000000 00000000 00000000
> >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> >  ---[ end trace 4017fea4906ab391 ]---
> >
> > But accordingly to Allwinner A33, A64 BSP codes [1] [2] this divider
> > is clearly using 'format/lanes' for dsi divider value, dsi_clk.clk_div
> >
> > Which would compute the pll_freq and set a clock rate for it in
> > [3] and [4] respectively.
> >
> > The same issue has reproduced in A33, A64 with 4-lane and 2-lane devices
> > and got fixed with this computation logic 'format/lanes', so this patch
> > using dclk min and max dividers as per BSP.
> >
> > [1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1106
> > [2] https://github.com/BPI-SINOVOIP/BPI-M64-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/disp_al.c#L213
> > [3] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1127
> > [4] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1161
>
> In that mail, I've pointed out that clk_div isn't used for the TCON dclk divider:
> http://lists.infradead.org/pipermail/linux-arm-kernel/2019-February/629596.html
>
> The only reply you've sent is that you indeed see that the divider is
> set to 4 in the BSP, but you're now saying that the BSP can change
> it. If so, then please point exactly the flaw in the explanation in
> that mail.

Frankly, I have explained these details in commit message and previous
version patch[1] with print messages on the code.

BSP has tcon_div and dsi_div. dsi_div is dynamic which depends on
bpp/lanes and it indeed depends on PLL computation (not tcon_div),
anyway I have explained again on this initial link you mentioned.
Please have a look and get back.

[1] https://patchwork.freedesktop.org/patch/291525/

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-05-23 20:34   ` Maxime Ripard
@ 2019-05-24 10:18     ` Jagan Teki
  2019-05-29 14:54       ` Maxime Ripard
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-05-24 10:18 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Fri, May 24, 2019 at 2:04 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Mon, May 20, 2019 at 02:33:08PM +0530, Jagan Teki wrote:
> > According to "DRM kernel-internal display mode structure" in
> > include/drm/drm_modes.h the current driver is trying to include
> > sync timings along with front porch value while checking and
> > computing drq set bits in non-burst mode.
> >
> > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> >
> > With adding additional sync timings, the dsi controller leads to
> > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > trigger panel flip_done timed out as:
> >
> >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> >  [CRTC:46:crtc-0] vblank wait timed out
> >  Modules linked in:
> >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
> >  Hardware name: Allwinner sun8i Family
> >  Workqueue: events deferred_probe_work_func
> >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> >  Exception stack(0xde539fb0 to 0xde539ff8)
> >  9fa0:                                     00000000 00000000 00000000 00000000
> >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> >  ---[ end trace b57eb1e5c64c6b8b ]---
> >  random: fast init done
> >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> >
> > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > non-burst DSI mode can be computed based on "horizontal front porch"
> > value only (no sync timings included).
> >
> > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> >
> > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > => tt->hor_front_porch - 20
>
> The thing is, while your explanation on the DRM side is sound,
> Allwinner has been using the hbp field of their panel description to
> store what DRM calls the backporch and the sync period.

Exactly, hbp = backporch + sync
https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046

And the above computation is rely on that as well. If you can see the
final out of the above computation you can get the front porch value
(w/o sync )

>
> And nowhere in that commit log you are describing whether it's still
> an issue or not, and if it's not anymore how you did test that it's
> not the case anymore.

No, I have explained 1st and 2nd para about
00. There is any additional sync timings in the drq set bits
01: issue occur due to adding addition sync timings with longs on the
panel, by referring
03: and later paragraphs proved that there is no sync timings used in BSP

Am I missing anythings?

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 02/11] drm/sun4i: dsi: Update start value in video start delay
  2019-05-23 20:37   ` Maxime Ripard
@ 2019-05-24 10:25     ` Jagan Teki
  2019-05-30 10:42       ` Maxime Ripard
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-05-24 10:25 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Fri, May 24, 2019 at 2:07 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Mon, May 20, 2019 at 02:33:09PM +0530, Jagan Teki wrote:
> > start value in video start delay computation done in below commit
> > is as per the legacy bsp drivers/video/sunxi/legacy..
> > "drm/sun4i: dsi: Change the start delay calculation"
> > (sha1: da676c6aa6413d59ab0a80c97bbc273025e640b2)
> >
> > This existing start delay computation gives start value of 35,
> > for "bananapi,s070wv20-ct16" panel timings which indeed trigger
> > panel flip_done timed out as:
> >
> >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> >  [CRTC:46:crtc-0] vblank wait timed out
> >  Modules linked in:
> >  CPU: 0 PID: 31 Comm: kworker/0:1 Tainted: G        W         5.1.0-next-20190514-00025-gf928bc7cc146 #15
> >  Hardware name: Allwinner sun8i Family
> >  Workqueue: events deferred_probe_work_func
> >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> >  [<c010b76c>] (show_stack) from [<c0688c90>] (dump_stack+0x84/0x98)
> >  [<c0688c90>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c0411cb0>] (drm_fb_helper_pan_display+0xac/0x1d0)
> >  [<c0411cb0>] (drm_fb_helper_pan_display) from [<c03a4e84>] (fb_pan_display+0xcc/0x134)
> >  [<c03a4e84>] (fb_pan_display) from [<c03b1214>] (bit_update_start+0x14/0x30)
> >  [<c03b1214>] (bit_update_start) from [<c03afe94>] (fbcon_switch+0x3d8/0x4e0)
> >  [<c03afe94>] (fbcon_switch) from [<c03ec930>] (redraw_screen+0x174/0x238)
> >  [<c03ec930>] (redraw_screen) from [<c03aceb4>] (fbcon_prepare_logo+0x3c4/0x400)
> >  [<c03aceb4>] (fbcon_prepare_logo) from [<c03ad2b8>] (fbcon_init+0x3c8/0x5ac)
> >  [<c03ad2b8>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> >  [<c043f060>] (sun4i_drv_bind) from [<c044b5b0>] (try_to_bring_up_master+0x164/0x1a0)
> >  [<c044b5b0>] (try_to_bring_up_master) from [<c044b680>] (__component_add+0x94/0x140)
> >  [<c044b680>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452f0c>] (platform_drv_probe+0x48/0x9c)
> >  [<c0452f0c>] (platform_drv_probe) from [<c04512e4>] (really_probe+0x1dc/0x2c8)
> >  [<c04512e4>] (really_probe) from [<c0451530>] (driver_probe_device+0x60/0x160)
> >  [<c0451530>] (driver_probe_device) from [<c044f7bc>] (bus_for_each_drv+0x74/0xb8)
> >  [<c044f7bc>] (bus_for_each_drv) from [<c0451094>] (__device_attach+0xd0/0x13c)
> >  [<c0451094>] (__device_attach) from [<c045048c>] (bus_probe_device+0x84/0x8c)
> >  [<c045048c>] (bus_probe_device) from [<c0450918>] (deferred_probe_work_func+0x64/0x90)
> >  [<c0450918>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> >  Exception stack(0xde539fb0 to 0xde539ff8)
> >  9fa0:                                     00000000 00000000 00000000 00000000
> >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> >  ---[ end trace 755e10f62b83f396 ]---
> >  Console: switching to colour frame buffer device 100x30
> >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> >
> > But the expected start delay value is 1 which is confirmed from
> > new bsp [2].
>
> If you're saying that the "legacy" link (second one) is the new BSP.

Will update, thanks.

>
> > The important and unclear note on legacy and new bsp codes [1] [2]
> > is both use similar start computation initially but it later reassign
> > it to 1 in new bsp.
>
> Then start_delay is never reassigned to 1 in that link, and is clamped
> between 8 and 100 as the code that you are removing is doing.

Please see the link one more please
https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L807

>
> > Unfortunately we don't have any evidence or documentation for this
> > reassignment to 1 in new bsp, but it is working with all supported
> > panels in A33, A64.
>
> No, it's not. That was added to fix a panel that is supported today.

No, I have see this in  A33, A64. and these are controller drivers
right, if it panel fix and it should be part of panel driver isn't it?

We can even see the same in pin64 longsleep kernel and others.

https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L807
https://github.com/longsleep/linux-pine64/blob/pine64-hacks-1.2/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/de_dsi.c#L730

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 03/11] drm/sun4i: dsi: Fix video start delay computation
  2019-05-23 20:38   ` Maxime Ripard
@ 2019-05-24 10:26     ` Jagan Teki
  2019-06-21  8:35       ` [linux-sunxi] " Chen-Yu Tsai
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-05-24 10:26 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Fri, May 24, 2019 at 2:18 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Mon, May 20, 2019 at 02:33:10PM +0530, Jagan Teki wrote:
> > The current code is computing vertical video start delay as
> >
> > delay = mode->vtotal - (mode->vsync_end - mode->vdisplay) + start;
> >
> > On which the second parameter
> >
> > mode->vsync_end - mode->vdisplay = front porch + sync timings
> >
> > according to "DRM kernel-internal display mode structure" in
> > include/drm/drm_modes.h
> >
> > With adding additional sync timings, the desired video start delay
> > value as 510 for "bananapi,s070wv20-ct16" panel timings which indeed
> > trigger panel flip_done timed out as:
> >
> >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> >  [CRTC:46:crtc-0] vblank wait timed out
> >  Modules linked in:
> >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00029-g09e5b0ed0a58 #18
> >  Hardware name: Allwinner sun8i Family
> >  Workqueue: events deferred_probe_work_func
> >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> >  Exception stack(0xde539fb0 to 0xde539ff8)
> >  9fa0:                                     00000000 00000000 00000000 00000000
> >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> >  ---[ end trace 495200a78b24980e ]---
> >  random: fast init done
> >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> >
> > But the expected video start delay value is 513 which states that
> > the second parameter on the computation is "front porch" value
> > (no sync timings included).
> >
> > This is clearly confirmed from the legacy [1] and new [2] bsp codes
> > that the second parameter on the video start delay is "front porch"
> >
> > Here is the detailed evidence for calculating front porch as per
> > bsp code.
> >
> > vfp = panel->lcd_vt - panel->lcd_y - panel->lcd_vbp
> > => (panel->lcd_vt) - panel->lcd_y - panel->lcd_vbp
> > => (tt->ver_front_porch + lcdp->panel_info.lcd_vbp
> >     + lcdp->panel_info.lcd_y) -  panel->lcd_y - panel->lcd_vbp
> > => tt->ver_front_porch
>
> The comment on patch 1 still applies on this patch

Thanks, I have responded on that. Same applies here.

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-05-24 10:18     ` Jagan Teki
@ 2019-05-29 14:54       ` Maxime Ripard
  2019-05-29 18:14         ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-05-29 14:54 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

[-- Attachment #1.1: Type: text/plain, Size: 7285 bytes --]

On Fri, May 24, 2019 at 03:48:51PM +0530, Jagan Teki wrote:
> On Fri, May 24, 2019 at 2:04 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> >
> > On Mon, May 20, 2019 at 02:33:08PM +0530, Jagan Teki wrote:
> > > According to "DRM kernel-internal display mode structure" in
> > > include/drm/drm_modes.h the current driver is trying to include
> > > sync timings along with front porch value while checking and
> > > computing drq set bits in non-burst mode.
> > >
> > > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> > >
> > > With adding additional sync timings, the dsi controller leads to
> > > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > > trigger panel flip_done timed out as:
> > >
> > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > >  [CRTC:46:crtc-0] vblank wait timed out
> > >  Modules linked in:
> > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
> > >  Hardware name: Allwinner sun8i Family
> > >  Workqueue: events deferred_probe_work_func
> > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> > >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> > >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> > >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> > >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> > >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> > >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> > >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> > >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> > >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > >  9fa0:                                     00000000 00000000 00000000 00000000
> > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > >  ---[ end trace b57eb1e5c64c6b8b ]---
> > >  random: fast init done
> > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > >
> > > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > > non-burst DSI mode can be computed based on "horizontal front porch"
> > > value only (no sync timings included).
> > >
> > > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> > >
> > > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > > => tt->hor_front_porch - 20
> >
> > The thing is, while your explanation on the DRM side is sound,
> > Allwinner has been using the hbp field of their panel description to
> > store what DRM calls the backporch and the sync period.
>
> Exactly, hbp = backporch + sync
> https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046
>
> And the above computation is rely on that as well. If you can see the
> final out of the above computation you can get the front porch value
> (w/o sync )

As I was saying, you are explaining it well for DRM, but in order for
your last formula (the one coming from the BSP) to make sense, you
have to explain that the horizontal back porch for Allwinner contains
the sync period, otherwise your expansion of lcd_ht doesn't make
sense.

> > And nowhere in that commit log you are describing whether it's still
> > an issue or not, and if it's not anymore how you did test that it's
> > not the case anymore.
>
> No, I have explained 1st and 2nd para about
> 00. There is any additional sync timings in the drq set bits
> 01: issue occur due to adding addition sync timings with longs on the
> panel, by referring
> 03: and later paragraphs proved that there is no sync timings used in BSP
>
> Am I missing anythings?

I'm sorry, but I'm not quite sure what you mean here :/

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-05-29 14:54       ` Maxime Ripard
@ 2019-05-29 18:14         ` Jagan Teki
  2019-06-04 10:00           ` Maxime Ripard
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-05-29 18:14 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Wed, May 29, 2019 at 8:24 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Fri, May 24, 2019 at 03:48:51PM +0530, Jagan Teki wrote:
> > On Fri, May 24, 2019 at 2:04 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > >
> > > On Mon, May 20, 2019 at 02:33:08PM +0530, Jagan Teki wrote:
> > > > According to "DRM kernel-internal display mode structure" in
> > > > include/drm/drm_modes.h the current driver is trying to include
> > > > sync timings along with front porch value while checking and
> > > > computing drq set bits in non-burst mode.
> > > >
> > > > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> > > >
> > > > With adding additional sync timings, the dsi controller leads to
> > > > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > > > trigger panel flip_done timed out as:
> > > >
> > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > >  Modules linked in:
> > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
> > > >  Hardware name: Allwinner sun8i Family
> > > >  Workqueue: events deferred_probe_work_func
> > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> > > >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> > > >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> > > >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> > > >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> > > >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> > > >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> > > >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> > > >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> > > >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > >  ---[ end trace b57eb1e5c64c6b8b ]---
> > > >  random: fast init done
> > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > >
> > > > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > > > non-burst DSI mode can be computed based on "horizontal front porch"
> > > > value only (no sync timings included).
> > > >
> > > > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> > > >
> > > > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > > > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > > > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > > > => tt->hor_front_porch - 20
> > >
> > > The thing is, while your explanation on the DRM side is sound,
> > > Allwinner has been using the hbp field of their panel description to
> > > store what DRM calls the backporch and the sync period.
> >
> > Exactly, hbp = backporch + sync
> > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046
> >
> > And the above computation is rely on that as well. If you can see the
> > final out of the above computation you can get the front porch value
> > (w/o sync )
>
> As I was saying, you are explaining it well for DRM, but in order for
> your last formula (the one coming from the BSP) to make sense, you
> have to explain that the horizontal back porch for Allwinner contains
> the sync period, otherwise your expansion of lcd_ht doesn't make
> sense.

I'm not sure why we need to take care of back porch since the formula
clearly evaluating a result as front porch, without sync timing (as
current code included this sync), I keep the hbp and trying to
substitute the lcd_ht value so the end result would cancel hbp.

I have used this front porch formula from BSP
tt->hor_front_porch= lcdp->panel_info.lcd_ht-lcdp->panel_info.lcd_hbp
- lcdp->panel_info.lcd_x;
https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2047

and evaluated drq set-bit formula

tt->hor_front_porch= lcdp->panel_info.lcd_ht-lcdp->panel_info.lcd_hbp
- lcdp->panel_info.lcd_x;
lcdp->panel_info.lcd_ht = tt->hor_front_porch +
lcdp->panel_info.lcd_hbp +  lcdp->panel_info.lcd_x

=> panel->lcd_ht - panel->lcd_x - panel->lcd_hbp
(substitute the lcd_ht)
=> tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
lcdp->panel_info.lcd_x - panel->lcd_x - panel->lcd_hbp
(here hbp and lcd_x would cancel, and the result is front porch)
=> tt->hor_front_porch

>
> > > And nowhere in that commit log you are describing whether it's still
> > > an issue or not, and if it's not anymore how you did test that it's
> > > not the case anymore.
> >
> > No, I have explained 1st and 2nd para about
> > 00. There is any additional sync timings in the drq set bits
> > 01: issue occur due to adding addition sync timings with longs on the
> > panel, by referring
> > 03: and later paragraphs proved that there is no sync timings used in BSP
> >
> > Am I missing anythings?
>
> I'm sorry, but I'm not quite sure what you mean here :/

I'm just mentioning how I fragmented/grouped the commit message.

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 02/11] drm/sun4i: dsi: Update start value in video start delay
  2019-05-24 10:25     ` Jagan Teki
@ 2019-05-30 10:42       ` Maxime Ripard
  2019-06-13  8:04         ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-05-30 10:42 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Fri, May 24, 2019 at 03:55:42PM +0530, Jagan Teki wrote:
> On Fri, May 24, 2019 at 2:07 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> >
> > On Mon, May 20, 2019 at 02:33:09PM +0530, Jagan Teki wrote:
> > > start value in video start delay computation done in below commit
> > > is as per the legacy bsp drivers/video/sunxi/legacy..
> > > "drm/sun4i: dsi: Change the start delay calculation"
> > > (sha1: da676c6aa6413d59ab0a80c97bbc273025e640b2)
> > >
> > > This existing start delay computation gives start value of 35,
> > > for "bananapi,s070wv20-ct16" panel timings which indeed trigger
> > > panel flip_done timed out as:
> > >
> > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > >  [CRTC:46:crtc-0] vblank wait timed out
> > >  Modules linked in:
> > >  CPU: 0 PID: 31 Comm: kworker/0:1 Tainted: G        W         5.1.0-next-20190514-00025-gf928bc7cc146 #15
> > >  Hardware name: Allwinner sun8i Family
> > >  Workqueue: events deferred_probe_work_func
> > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > >  [<c010b76c>] (show_stack) from [<c0688c90>] (dump_stack+0x84/0x98)
> > >  [<c0688c90>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c0411cb0>] (drm_fb_helper_pan_display+0xac/0x1d0)
> > >  [<c0411cb0>] (drm_fb_helper_pan_display) from [<c03a4e84>] (fb_pan_display+0xcc/0x134)
> > >  [<c03a4e84>] (fb_pan_display) from [<c03b1214>] (bit_update_start+0x14/0x30)
> > >  [<c03b1214>] (bit_update_start) from [<c03afe94>] (fbcon_switch+0x3d8/0x4e0)
> > >  [<c03afe94>] (fbcon_switch) from [<c03ec930>] (redraw_screen+0x174/0x238)
> > >  [<c03ec930>] (redraw_screen) from [<c03aceb4>] (fbcon_prepare_logo+0x3c4/0x400)
> > >  [<c03aceb4>] (fbcon_prepare_logo) from [<c03ad2b8>] (fbcon_init+0x3c8/0x5ac)
> > >  [<c03ad2b8>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > >  [<c043f060>] (sun4i_drv_bind) from [<c044b5b0>] (try_to_bring_up_master+0x164/0x1a0)
> > >  [<c044b5b0>] (try_to_bring_up_master) from [<c044b680>] (__component_add+0x94/0x140)
> > >  [<c044b680>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452f0c>] (platform_drv_probe+0x48/0x9c)
> > >  [<c0452f0c>] (platform_drv_probe) from [<c04512e4>] (really_probe+0x1dc/0x2c8)
> > >  [<c04512e4>] (really_probe) from [<c0451530>] (driver_probe_device+0x60/0x160)
> > >  [<c0451530>] (driver_probe_device) from [<c044f7bc>] (bus_for_each_drv+0x74/0xb8)
> > >  [<c044f7bc>] (bus_for_each_drv) from [<c0451094>] (__device_attach+0xd0/0x13c)
> > >  [<c0451094>] (__device_attach) from [<c045048c>] (bus_probe_device+0x84/0x8c)
> > >  [<c045048c>] (bus_probe_device) from [<c0450918>] (deferred_probe_work_func+0x64/0x90)
> > >  [<c0450918>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > >  9fa0:                                     00000000 00000000 00000000 00000000
> > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > >  ---[ end trace 755e10f62b83f396 ]---
> > >  Console: switching to colour frame buffer device 100x30
> > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > >
> > > But the expected start delay value is 1 which is confirmed from
> > > new bsp [2].
> >
> > If you're saying that the "legacy" link (second one) is the new BSP.
>
> Will update, thanks.
>
> >
> > > The important and unclear note on legacy and new bsp codes [1] [2]
> > > is both use similar start computation initially but it later reassign
> > > it to 1 in new bsp.
> >
> > Then start_delay is never reassigned to 1 in that link, and is clamped
> > between 8 and 100 as the code that you are removing is doing.
>
> Please see the link one more please
> https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L807
>
> >
> > > Unfortunately we don't have any evidence or documentation for this
> > > reassignment to 1 in new bsp, but it is working with all supported
> > > panels in A33, A64.
> >
> > No, it's not. That was added to fix a panel that is supported today.
>
> No, I have see this in A33, A64. and these are controller drivers
> right, if it panel fix and it should be part of panel driver isn't
> it?

I'm not sure to follow that argument. You're submitting that fix to
allow other panels to work, right? So surely, some issues that can be
found using a given panel might not be solely fixed in the panel driver.

> We can even see the same in pin64 longsleep kernel and others.
>
> https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L807
> https://github.com/longsleep/linux-pine64/blob/pine64-hacks-1.2/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/de_dsi.c#L730

Yeah, and both of these have the legacy driver part with the clamping
too.

I'll test these patches again some time next week

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 09/11] drm/sun4i: sun6i_mipi_dsi: Add VCC-DSI regulator support
  2019-05-20  9:03 ` [PATCH v10 09/11] drm/sun4i: sun6i_mipi_dsi: Add VCC-DSI regulator support Jagan Teki
@ 2019-06-03 13:49   ` Maxime Ripard
  2019-06-13  7:55     ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-06-03 13:49 UTC (permalink / raw)
  To: Jagan Teki
  Cc: bshah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	powerpan, Chen-Yu Tsai, Daniel Vetter, michael, linux-amarula,
	linux-arm-kernel

[-- Attachment #1.1: Type: text/plain, Size: 539 bytes --]

On Mon, May 20, 2019 at 02:33:16PM +0530, Jagan Teki wrote:
> Allwinner MIPI DSI controllers are supplied with SoC
> DSI power rails via VCC-DSI pin.
>
> Add support for this supply pin by adding voltage
> regulator handling code to MIPI DSI driver.
>
> Tested-by: Merlijn Wajer <merlijn@wizzup.org>
> Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>

This creates a lot of warnings at boot time on my board this is
missing vcc-dsi-supply.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

[-- Attachment #1.2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]

[-- Attachment #2: Type: text/plain, Size: 176 bytes --]

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-05-29 18:14         ` Jagan Teki
@ 2019-06-04 10:00           ` Maxime Ripard
  2019-06-05  7:47             ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-06-04 10:00 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

[-- Attachment #1.1: Type: text/plain, Size: 7863 bytes --]

On Wed, May 29, 2019 at 11:44:56PM +0530, Jagan Teki wrote:
> On Wed, May 29, 2019 at 8:24 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> >
> > On Fri, May 24, 2019 at 03:48:51PM +0530, Jagan Teki wrote:
> > > On Fri, May 24, 2019 at 2:04 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > >
> > > > On Mon, May 20, 2019 at 02:33:08PM +0530, Jagan Teki wrote:
> > > > > According to "DRM kernel-internal display mode structure" in
> > > > > include/drm/drm_modes.h the current driver is trying to include
> > > > > sync timings along with front porch value while checking and
> > > > > computing drq set bits in non-burst mode.
> > > > >
> > > > > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> > > > >
> > > > > With adding additional sync timings, the dsi controller leads to
> > > > > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > > > > trigger panel flip_done timed out as:
> > > > >
> > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > >  Modules linked in:
> > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
> > > > >  Hardware name: Allwinner sun8i Family
> > > > >  Workqueue: events deferred_probe_work_func
> > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> > > > >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> > > > >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> > > > >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> > > > >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> > > > >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> > > > >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> > > > >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> > > > >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> > > > >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > >  ---[ end trace b57eb1e5c64c6b8b ]---
> > > > >  random: fast init done
> > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > > >
> > > > > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > > > > non-burst DSI mode can be computed based on "horizontal front porch"
> > > > > value only (no sync timings included).
> > > > >
> > > > > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> > > > >
> > > > > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > > > > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > > > > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > > > > => tt->hor_front_porch - 20
> > > >
> > > > The thing is, while your explanation on the DRM side is sound,
> > > > Allwinner has been using the hbp field of their panel description to
> > > > store what DRM calls the backporch and the sync period.
> > >
> > > Exactly, hbp = backporch + sync
> > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046
> > >
> > > And the above computation is rely on that as well. If you can see the
> > > final out of the above computation you can get the front porch value
> > > (w/o sync )
> >
> > As I was saying, you are explaining it well for DRM, but in order for
> > your last formula (the one coming from the BSP) to make sense, you
> > have to explain that the horizontal back porch for Allwinner contains
> > the sync period, otherwise your expansion of lcd_ht doesn't make
> > sense.
>
> I'm not sure why we need to take care of back porch since the formula
> clearly evaluating a result as front porch, without sync timing (as
> current code included this sync), I keep the hbp and trying to
> substitute the lcd_ht value so the end result would cancel hbp.

Because it changes how lcd_ht expands. In the DRM case, it will expand
to the displayed area, the front porch, the sync period and the back
porch.

In your case, you expand it to the displayed area, the front porch and
the back porch, precisely because in Allwinner's case, the back porch
has the sync period.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes
  2019-05-24 10:07     ` Jagan Teki
@ 2019-06-04 14:30       ` Maxime Ripard
  2019-06-05  7:41         ` [linux-sunxi] " Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-06-04 14:30 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

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On Fri, May 24, 2019 at 03:37:36PM +0530, Jagan Teki wrote:
> On Fri, May 24, 2019 at 2:18 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> >
> > On Mon, May 20, 2019 at 02:33:11PM +0530, Jagan Teki wrote:
> > > pll-video => pll-mipi => tcon0 => tcon0-pixel-clock is the typical
> > > MIPI clock topology in Allwinner DSI controller.
> > >
> > > TCON dotclock driver is computing the desired DCLK divider based on
> > > panel pixel clock along with input DCLK min, max divider values from
> > > tcon driver and that would eventually set the pll-mipi clock rate.
> > >
> > > The current code is passing dsi min and max divider value as 4 via
> > > tcon driver which would ended-up triggering below vblank wait timed out
> > > warning on "bananapi,s070wv20-ct16" panel.
> > >
> > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > >  [CRTC:46:crtc-0] vblank wait timed out
> > >  Modules linked in:
> > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00025-g5186cdf10757-dirty #6
> > >  Hardware name: Allwinner sun8i Family
> > >  Workqueue: events deferred_probe_work_func
> > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > >  [<c043f060>] (sun4i_drv_bind) from [<c044b588>] (try_to_bring_up_master+0x164/0x1a0)
> > >  [<c044b588>] (try_to_bring_up_master) from [<c044b658>] (__component_add+0x94/0x140)
> > >  [<c044b658>] (__component_add) from [<c0445e0c>] (sun6i_dsi_probe+0x144/0x234)
> > >  [<c0445e0c>] (sun6i_dsi_probe) from [<c0452ee4>] (platform_drv_probe+0x48/0x9c)
> > >  [<c0452ee4>] (platform_drv_probe) from [<c04512bc>] (really_probe+0x1dc/0x2c8)
> > >  [<c04512bc>] (really_probe) from [<c0451508>] (driver_probe_device+0x60/0x160)
> > >  [<c0451508>] (driver_probe_device) from [<c044f794>] (bus_for_each_drv+0x74/0xb8)
> > >  [<c044f794>] (bus_for_each_drv) from [<c045106c>] (__device_attach+0xd0/0x13c)
> > >  [<c045106c>] (__device_attach) from [<c0450464>] (bus_probe_device+0x84/0x8c)
> > >  [<c0450464>] (bus_probe_device) from [<c04508f0>] (deferred_probe_work_func+0x64/0x90)
> > >  [<c04508f0>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > >  9fa0:                                     00000000 00000000 00000000 00000000
> > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > >  ---[ end trace 4017fea4906ab391 ]---
> > >
> > > But accordingly to Allwinner A33, A64 BSP codes [1] [2] this divider
> > > is clearly using 'format/lanes' for dsi divider value, dsi_clk.clk_div
> > >
> > > Which would compute the pll_freq and set a clock rate for it in
> > > [3] and [4] respectively.
> > >
> > > The same issue has reproduced in A33, A64 with 4-lane and 2-lane devices
> > > and got fixed with this computation logic 'format/lanes', so this patch
> > > using dclk min and max dividers as per BSP.
> > >
> > > [1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1106
> > > [2] https://github.com/BPI-SINOVOIP/BPI-M64-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/disp_al.c#L213
> > > [3] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1127
> > > [4] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1161
> >
> > In that mail, I've pointed out that clk_div isn't used for the TCON dclk divider:
> > http://lists.infradead.org/pipermail/linux-arm-kernel/2019-February/629596.html
> >
> > The only reply you've sent is that you indeed see that the divider is
> > set to 4 in the BSP, but you're now saying that the BSP can change
> > it. If so, then please point exactly the flaw in the explanation in
> > that mail.
>
> Frankly, I have explained these details in commit message and previous
> version patch[1] with print messages on the code.
>
> BSP has tcon_div and dsi_div. dsi_div is dynamic which depends on
> bpp/lanes and it indeed depends on PLL computation (not tcon_div),
> anyway I have explained again on this initial link you mentioned.
> Please have a look and get back.

I'll have a look, thanks.

I've given your patches a try on my setup though, and this patch
breaks it with vblank timeouts and some horizontal lines that looks
like what should be displayed, but blinking and on the right of the
display. The previous ones are fine though.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes
  2019-06-04 14:30       ` Maxime Ripard
@ 2019-06-05  7:41         ` " Jagan Teki
  2019-06-13 13:16           ` Maxime Ripard
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-06-05  7:41 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Tue, Jun 4, 2019 at 8:00 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Fri, May 24, 2019 at 03:37:36PM +0530, Jagan Teki wrote:
> > On Fri, May 24, 2019 at 2:18 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > >
> > > On Mon, May 20, 2019 at 02:33:11PM +0530, Jagan Teki wrote:
> > > > pll-video => pll-mipi => tcon0 => tcon0-pixel-clock is the typical
> > > > MIPI clock topology in Allwinner DSI controller.
> > > >
> > > > TCON dotclock driver is computing the desired DCLK divider based on
> > > > panel pixel clock along with input DCLK min, max divider values from
> > > > tcon driver and that would eventually set the pll-mipi clock rate.
> > > >
> > > > The current code is passing dsi min and max divider value as 4 via
> > > > tcon driver which would ended-up triggering below vblank wait timed out
> > > > warning on "bananapi,s070wv20-ct16" panel.
> > > >
> > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > >  Modules linked in:
> > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00025-g5186cdf10757-dirty #6
> > > >  Hardware name: Allwinner sun8i Family
> > > >  Workqueue: events deferred_probe_work_func
> > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b588>] (try_to_bring_up_master+0x164/0x1a0)
> > > >  [<c044b588>] (try_to_bring_up_master) from [<c044b658>] (__component_add+0x94/0x140)
> > > >  [<c044b658>] (__component_add) from [<c0445e0c>] (sun6i_dsi_probe+0x144/0x234)
> > > >  [<c0445e0c>] (sun6i_dsi_probe) from [<c0452ee4>] (platform_drv_probe+0x48/0x9c)
> > > >  [<c0452ee4>] (platform_drv_probe) from [<c04512bc>] (really_probe+0x1dc/0x2c8)
> > > >  [<c04512bc>] (really_probe) from [<c0451508>] (driver_probe_device+0x60/0x160)
> > > >  [<c0451508>] (driver_probe_device) from [<c044f794>] (bus_for_each_drv+0x74/0xb8)
> > > >  [<c044f794>] (bus_for_each_drv) from [<c045106c>] (__device_attach+0xd0/0x13c)
> > > >  [<c045106c>] (__device_attach) from [<c0450464>] (bus_probe_device+0x84/0x8c)
> > > >  [<c0450464>] (bus_probe_device) from [<c04508f0>] (deferred_probe_work_func+0x64/0x90)
> > > >  [<c04508f0>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > >  ---[ end trace 4017fea4906ab391 ]---
> > > >
> > > > But accordingly to Allwinner A33, A64 BSP codes [1] [2] this divider
> > > > is clearly using 'format/lanes' for dsi divider value, dsi_clk.clk_div
> > > >
> > > > Which would compute the pll_freq and set a clock rate for it in
> > > > [3] and [4] respectively.
> > > >
> > > > The same issue has reproduced in A33, A64 with 4-lane and 2-lane devices
> > > > and got fixed with this computation logic 'format/lanes', so this patch
> > > > using dclk min and max dividers as per BSP.
> > > >
> > > > [1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1106
> > > > [2] https://github.com/BPI-SINOVOIP/BPI-M64-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/disp_al.c#L213
> > > > [3] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1127
> > > > [4] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1161
> > >
> > > In that mail, I've pointed out that clk_div isn't used for the TCON dclk divider:
> > > http://lists.infradead.org/pipermail/linux-arm-kernel/2019-February/629596.html
> > >
> > > The only reply you've sent is that you indeed see that the divider is
> > > set to 4 in the BSP, but you're now saying that the BSP can change
> > > it. If so, then please point exactly the flaw in the explanation in
> > > that mail.
> >
> > Frankly, I have explained these details in commit message and previous
> > version patch[1] with print messages on the code.
> >
> > BSP has tcon_div and dsi_div. dsi_div is dynamic which depends on
> > bpp/lanes and it indeed depends on PLL computation (not tcon_div),
> > anyway I have explained again on this initial link you mentioned.
> > Please have a look and get back.
>
> I'll have a look, thanks.
>
> I've given your patches a try on my setup though, and this patch
> breaks it with vblank timeouts and some horizontal lines that looks
> like what should be displayed, but blinking and on the right of the
> display. The previous ones are fine though.

Would you please send me the link of panel driver.

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http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-06-04 10:00           ` Maxime Ripard
@ 2019-06-05  7:47             ` Jagan Teki
  2019-06-13 12:56               ` Maxime Ripard
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-06-05  7:47 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Tue, Jun 4, 2019 at 3:30 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Wed, May 29, 2019 at 11:44:56PM +0530, Jagan Teki wrote:
> > On Wed, May 29, 2019 at 8:24 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > >
> > > On Fri, May 24, 2019 at 03:48:51PM +0530, Jagan Teki wrote:
> > > > On Fri, May 24, 2019 at 2:04 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > >
> > > > > On Mon, May 20, 2019 at 02:33:08PM +0530, Jagan Teki wrote:
> > > > > > According to "DRM kernel-internal display mode structure" in
> > > > > > include/drm/drm_modes.h the current driver is trying to include
> > > > > > sync timings along with front porch value while checking and
> > > > > > computing drq set bits in non-burst mode.
> > > > > >
> > > > > > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> > > > > >
> > > > > > With adding additional sync timings, the dsi controller leads to
> > > > > > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > > > > > trigger panel flip_done timed out as:
> > > > > >
> > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > >  Modules linked in:
> > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
> > > > > >  Hardware name: Allwinner sun8i Family
> > > > > >  Workqueue: events deferred_probe_work_func
> > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> > > > > >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> > > > > >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> > > > > >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> > > > > >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> > > > > >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> > > > > >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> > > > > >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> > > > > >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > >  ---[ end trace b57eb1e5c64c6b8b ]---
> > > > > >  random: fast init done
> > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > > > >
> > > > > > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > > > > > non-burst DSI mode can be computed based on "horizontal front porch"
> > > > > > value only (no sync timings included).
> > > > > >
> > > > > > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> > > > > >
> > > > > > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > > > > > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > => tt->hor_front_porch - 20
> > > > >
> > > > > The thing is, while your explanation on the DRM side is sound,
> > > > > Allwinner has been using the hbp field of their panel description to
> > > > > store what DRM calls the backporch and the sync period.
> > > >
> > > > Exactly, hbp = backporch + sync
> > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046
> > > >
> > > > And the above computation is rely on that as well. If you can see the
> > > > final out of the above computation you can get the front porch value
> > > > (w/o sync )
> > >
> > > As I was saying, you are explaining it well for DRM, but in order for
> > > your last formula (the one coming from the BSP) to make sense, you
> > > have to explain that the horizontal back porch for Allwinner contains
> > > the sync period, otherwise your expansion of lcd_ht doesn't make
> > > sense.
> >
> > I'm not sure why we need to take care of back porch since the formula
> > clearly evaluating a result as front porch, without sync timing (as
> > current code included this sync), I keep the hbp and trying to
> > substitute the lcd_ht value so the end result would cancel hbp.
>
> Because it changes how lcd_ht expands. In the DRM case, it will expand
> to the displayed area, the front porch, the sync period and the back
> porch.
>
> In your case, you expand it to the displayed area, the front porch and
> the back porch, precisely because in Allwinner's case, the back porch
> has the sync period.

I understand the point, but technically it matter about the final
computation result.  May be we can even manage the same computation in
back porch, but I'm not sure. Since the final output doesn't involve
any sync length, why we can include that ie what I'm not sure. with
inclusion of sync timings we have wrong tcon drq set bit, it's been
verified.

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http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 09/11] drm/sun4i: sun6i_mipi_dsi: Add VCC-DSI regulator support
  2019-06-03 13:49   ` Maxime Ripard
@ 2019-06-13  7:55     ` Jagan Teki
  2019-06-13 13:14       ` Maxime Ripard
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-06-13  7:55 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Mon, Jun 3, 2019 at 7:19 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Mon, May 20, 2019 at 02:33:16PM +0530, Jagan Teki wrote:
> > Allwinner MIPI DSI controllers are supplied with SoC
> > DSI power rails via VCC-DSI pin.
> >
> > Add support for this supply pin by adding voltage
> > regulator handling code to MIPI DSI driver.
> >
> > Tested-by: Merlijn Wajer <merlijn@wizzup.org>
> > Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
>
> This creates a lot of warnings at boot time on my board this is
> missing vcc-dsi-supply.

Is it about regulator_put or similar, would you provide the log.

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 02/11] drm/sun4i: dsi: Update start value in video start delay
  2019-05-30 10:42       ` Maxime Ripard
@ 2019-06-13  8:04         ` Jagan Teki
  2019-06-14 14:28           ` Maxime Ripard
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-06-13  8:04 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Fri, May 31, 2019 at 12:23 AM Maxime Ripard
<maxime.ripard@bootlin.com> wrote:
>
> On Fri, May 24, 2019 at 03:55:42PM +0530, Jagan Teki wrote:
> > On Fri, May 24, 2019 at 2:07 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > >
> > > On Mon, May 20, 2019 at 02:33:09PM +0530, Jagan Teki wrote:
> > > > start value in video start delay computation done in below commit
> > > > is as per the legacy bsp drivers/video/sunxi/legacy..
> > > > "drm/sun4i: dsi: Change the start delay calculation"
> > > > (sha1: da676c6aa6413d59ab0a80c97bbc273025e640b2)
> > > >
> > > > This existing start delay computation gives start value of 35,
> > > > for "bananapi,s070wv20-ct16" panel timings which indeed trigger
> > > > panel flip_done timed out as:
> > > >
> > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > >  Modules linked in:
> > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Tainted: G        W         5.1.0-next-20190514-00025-gf928bc7cc146 #15
> > > >  Hardware name: Allwinner sun8i Family
> > > >  Workqueue: events deferred_probe_work_func
> > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > >  [<c010b76c>] (show_stack) from [<c0688c90>] (dump_stack+0x84/0x98)
> > > >  [<c0688c90>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c0411cb0>] (drm_fb_helper_pan_display+0xac/0x1d0)
> > > >  [<c0411cb0>] (drm_fb_helper_pan_display) from [<c03a4e84>] (fb_pan_display+0xcc/0x134)
> > > >  [<c03a4e84>] (fb_pan_display) from [<c03b1214>] (bit_update_start+0x14/0x30)
> > > >  [<c03b1214>] (bit_update_start) from [<c03afe94>] (fbcon_switch+0x3d8/0x4e0)
> > > >  [<c03afe94>] (fbcon_switch) from [<c03ec930>] (redraw_screen+0x174/0x238)
> > > >  [<c03ec930>] (redraw_screen) from [<c03aceb4>] (fbcon_prepare_logo+0x3c4/0x400)
> > > >  [<c03aceb4>] (fbcon_prepare_logo) from [<c03ad2b8>] (fbcon_init+0x3c8/0x5ac)
> > > >  [<c03ad2b8>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b5b0>] (try_to_bring_up_master+0x164/0x1a0)
> > > >  [<c044b5b0>] (try_to_bring_up_master) from [<c044b680>] (__component_add+0x94/0x140)
> > > >  [<c044b680>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452f0c>] (platform_drv_probe+0x48/0x9c)
> > > >  [<c0452f0c>] (platform_drv_probe) from [<c04512e4>] (really_probe+0x1dc/0x2c8)
> > > >  [<c04512e4>] (really_probe) from [<c0451530>] (driver_probe_device+0x60/0x160)
> > > >  [<c0451530>] (driver_probe_device) from [<c044f7bc>] (bus_for_each_drv+0x74/0xb8)
> > > >  [<c044f7bc>] (bus_for_each_drv) from [<c0451094>] (__device_attach+0xd0/0x13c)
> > > >  [<c0451094>] (__device_attach) from [<c045048c>] (bus_probe_device+0x84/0x8c)
> > > >  [<c045048c>] (bus_probe_device) from [<c0450918>] (deferred_probe_work_func+0x64/0x90)
> > > >  [<c0450918>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > >  ---[ end trace 755e10f62b83f396 ]---
> > > >  Console: switching to colour frame buffer device 100x30
> > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > >
> > > > But the expected start delay value is 1 which is confirmed from
> > > > new bsp [2].
> > >
> > > If you're saying that the "legacy" link (second one) is the new BSP.
> >
> > Will update, thanks.
> >
> > >
> > > > The important and unclear note on legacy and new bsp codes [1] [2]
> > > > is both use similar start computation initially but it later reassign
> > > > it to 1 in new bsp.
> > >
> > > Then start_delay is never reassigned to 1 in that link, and is clamped
> > > between 8 and 100 as the code that you are removing is doing.
> >
> > Please see the link one more please
> > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L807
> >
> > >
> > > > Unfortunately we don't have any evidence or documentation for this
> > > > reassignment to 1 in new bsp, but it is working with all supported
> > > > panels in A33, A64.
> > >
> > > No, it's not. That was added to fix a panel that is supported today.
> >
> > No, I have see this in A33, A64. and these are controller drivers
> > right, if it panel fix and it should be part of panel driver isn't
> > it?
>
> I'm not sure to follow that argument. You're submitting that fix to
> allow other panels to work, right? So surely, some issues that can be
> found using a given panel might not be solely fixed in the panel driver.

I'm not sure I understand this. I have been verifying different panels
to check across. and this change literally in BSP and the BSP code is
using this based on the logs confirmation. all the logs and working
conditions shows that the fix would required in dsi.

>
> > We can even see the same in pin64 longsleep kernel and others.
> >
> > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L807
> > https://github.com/longsleep/linux-pine64/blob/pine64-hacks-1.2/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/de_dsi.c#L730
>
> Yeah, and both of these have the legacy driver part with the clamping
> too.

Yes, both legacy has clamping, but not using. they used it in new
version driver which I'm referring above.

>
> I'll test these patches again some time next week

Any help on the testing.

_______________________________________________
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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-06-05  7:47             ` Jagan Teki
@ 2019-06-13 12:56               ` Maxime Ripard
  2019-06-14  6:33                 ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-06-13 12:56 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

[-- Attachment #1.1: Type: text/plain, Size: 9124 bytes --]

On Wed, Jun 05, 2019 at 01:17:11PM +0530, Jagan Teki wrote:
> On Tue, Jun 4, 2019 at 3:30 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> >
> > On Wed, May 29, 2019 at 11:44:56PM +0530, Jagan Teki wrote:
> > > On Wed, May 29, 2019 at 8:24 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > >
> > > > On Fri, May 24, 2019 at 03:48:51PM +0530, Jagan Teki wrote:
> > > > > On Fri, May 24, 2019 at 2:04 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > >
> > > > > > On Mon, May 20, 2019 at 02:33:08PM +0530, Jagan Teki wrote:
> > > > > > > According to "DRM kernel-internal display mode structure" in
> > > > > > > include/drm/drm_modes.h the current driver is trying to include
> > > > > > > sync timings along with front porch value while checking and
> > > > > > > computing drq set bits in non-burst mode.
> > > > > > >
> > > > > > > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> > > > > > >
> > > > > > > With adding additional sync timings, the dsi controller leads to
> > > > > > > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > > > > > > trigger panel flip_done timed out as:
> > > > > > >
> > > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > > >  Modules linked in:
> > > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
> > > > > > >  Hardware name: Allwinner sun8i Family
> > > > > > >  Workqueue: events deferred_probe_work_func
> > > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > > >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> > > > > > >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> > > > > > >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> > > > > > >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> > > > > > >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> > > > > > >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> > > > > > >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> > > > > > >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> > > > > > >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > > >  ---[ end trace b57eb1e5c64c6b8b ]---
> > > > > > >  random: fast init done
> > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > > > > >
> > > > > > > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > > > > > > non-burst DSI mode can be computed based on "horizontal front porch"
> > > > > > > value only (no sync timings included).
> > > > > > >
> > > > > > > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> > > > > > >
> > > > > > > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > > > > > > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > => tt->hor_front_porch - 20
> > > > > >
> > > > > > The thing is, while your explanation on the DRM side is sound,
> > > > > > Allwinner has been using the hbp field of their panel description to
> > > > > > store what DRM calls the backporch and the sync period.
> > > > >
> > > > > Exactly, hbp = backporch + sync
> > > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046
> > > > >
> > > > > And the above computation is rely on that as well. If you can see the
> > > > > final out of the above computation you can get the front porch value
> > > > > (w/o sync )
> > > >
> > > > As I was saying, you are explaining it well for DRM, but in order for
> > > > your last formula (the one coming from the BSP) to make sense, you
> > > > have to explain that the horizontal back porch for Allwinner contains
> > > > the sync period, otherwise your expansion of lcd_ht doesn't make
> > > > sense.
> > >
> > > I'm not sure why we need to take care of back porch since the formula
> > > clearly evaluating a result as front porch, without sync timing (as
> > > current code included this sync), I keep the hbp and trying to
> > > substitute the lcd_ht value so the end result would cancel hbp.
> >
> > Because it changes how lcd_ht expands. In the DRM case, it will expand
> > to the displayed area, the front porch, the sync period and the back
> > porch.
> >
> > In your case, you expand it to the displayed area, the front porch and
> > the back porch, precisely because in Allwinner's case, the back porch
> > has the sync period.
>
> I understand the point, but technically it matter about the final
> computation result.  May be we can even manage the same computation in
> back porch, but I'm not sure. Since the final output doesn't involve
> any sync length, why we can include that ie what I'm not sure.

We have the following formula:
lcd_ht - lcd_x - lcd_hbp - 20

Using the concepts as they are defined in DRM, this expands to:
x + hbp + hsync + hfp - x - hbp - 20

which ends up as
hsync + hfp - 20

Now, the same formula with how Allwinner defines it:
x + hbp + hfp - x - hbp - 20

which ends up as
hfp - 20

So it definitely matters, and the sync period is used in one but not
the other.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 09/11] drm/sun4i: sun6i_mipi_dsi: Add VCC-DSI regulator support
  2019-06-13  7:55     ` Jagan Teki
@ 2019-06-13 13:14       ` Maxime Ripard
  0 siblings, 0 replies; 54+ messages in thread
From: Maxime Ripard @ 2019-06-13 13:14 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

[-- Attachment #1.1: Type: text/plain, Size: 847 bytes --]

On Thu, Jun 13, 2019 at 01:25:52PM +0530, Jagan Teki wrote:
> On Mon, Jun 3, 2019 at 7:19 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> >
> > On Mon, May 20, 2019 at 02:33:16PM +0530, Jagan Teki wrote:
> > > Allwinner MIPI DSI controllers are supplied with SoC
> > > DSI power rails via VCC-DSI pin.
> > >
> > > Add support for this supply pin by adding voltage
> > > regulator handling code to MIPI DSI driver.
> > >
> > > Tested-by: Merlijn Wajer <merlijn@wizzup.org>
> > > Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
> >
> > This creates a lot of warnings at boot time on my board this is
> > missing vcc-dsi-supply.
>
> Is it about regulator_put or similar, would you provide the log.

Sure
http://code.bulix.org/whiea9-769551?raw

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes
  2019-06-05  7:41         ` [linux-sunxi] " Jagan Teki
@ 2019-06-13 13:16           ` Maxime Ripard
  2019-06-14 12:03             ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-06-13 13:16 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

[-- Attachment #1.1: Type: text/plain, Size: 7870 bytes --]

On Wed, Jun 05, 2019 at 01:11:44PM +0530, Jagan Teki wrote:
> On Tue, Jun 4, 2019 at 8:00 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> >
> > On Fri, May 24, 2019 at 03:37:36PM +0530, Jagan Teki wrote:
> > > On Fri, May 24, 2019 at 2:18 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > >
> > > > On Mon, May 20, 2019 at 02:33:11PM +0530, Jagan Teki wrote:
> > > > > pll-video => pll-mipi => tcon0 => tcon0-pixel-clock is the typical
> > > > > MIPI clock topology in Allwinner DSI controller.
> > > > >
> > > > > TCON dotclock driver is computing the desired DCLK divider based on
> > > > > panel pixel clock along with input DCLK min, max divider values from
> > > > > tcon driver and that would eventually set the pll-mipi clock rate.
> > > > >
> > > > > The current code is passing dsi min and max divider value as 4 via
> > > > > tcon driver which would ended-up triggering below vblank wait timed out
> > > > > warning on "bananapi,s070wv20-ct16" panel.
> > > > >
> > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > >  Modules linked in:
> > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00025-g5186cdf10757-dirty #6
> > > > >  Hardware name: Allwinner sun8i Family
> > > > >  Workqueue: events deferred_probe_work_func
> > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b588>] (try_to_bring_up_master+0x164/0x1a0)
> > > > >  [<c044b588>] (try_to_bring_up_master) from [<c044b658>] (__component_add+0x94/0x140)
> > > > >  [<c044b658>] (__component_add) from [<c0445e0c>] (sun6i_dsi_probe+0x144/0x234)
> > > > >  [<c0445e0c>] (sun6i_dsi_probe) from [<c0452ee4>] (platform_drv_probe+0x48/0x9c)
> > > > >  [<c0452ee4>] (platform_drv_probe) from [<c04512bc>] (really_probe+0x1dc/0x2c8)
> > > > >  [<c04512bc>] (really_probe) from [<c0451508>] (driver_probe_device+0x60/0x160)
> > > > >  [<c0451508>] (driver_probe_device) from [<c044f794>] (bus_for_each_drv+0x74/0xb8)
> > > > >  [<c044f794>] (bus_for_each_drv) from [<c045106c>] (__device_attach+0xd0/0x13c)
> > > > >  [<c045106c>] (__device_attach) from [<c0450464>] (bus_probe_device+0x84/0x8c)
> > > > >  [<c0450464>] (bus_probe_device) from [<c04508f0>] (deferred_probe_work_func+0x64/0x90)
> > > > >  [<c04508f0>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > >  ---[ end trace 4017fea4906ab391 ]---
> > > > >
> > > > > But accordingly to Allwinner A33, A64 BSP codes [1] [2] this divider
> > > > > is clearly using 'format/lanes' for dsi divider value, dsi_clk.clk_div
> > > > >
> > > > > Which would compute the pll_freq and set a clock rate for it in
> > > > > [3] and [4] respectively.
> > > > >
> > > > > The same issue has reproduced in A33, A64 with 4-lane and 2-lane devices
> > > > > and got fixed with this computation logic 'format/lanes', so this patch
> > > > > using dclk min and max dividers as per BSP.
> > > > >
> > > > > [1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1106
> > > > > [2] https://github.com/BPI-SINOVOIP/BPI-M64-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/disp_al.c#L213
> > > > > [3] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1127
> > > > > [4] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1161
> > > >
> > > > In that mail, I've pointed out that clk_div isn't used for the TCON dclk divider:
> > > > http://lists.infradead.org/pipermail/linux-arm-kernel/2019-February/629596.html
> > > >
> > > > The only reply you've sent is that you indeed see that the divider is
> > > > set to 4 in the BSP, but you're now saying that the BSP can change
> > > > it. If so, then please point exactly the flaw in the explanation in
> > > > that mail.
> > >
> > > Frankly, I have explained these details in commit message and previous
> > > version patch[1] with print messages on the code.
> > >
> > > BSP has tcon_div and dsi_div. dsi_div is dynamic which depends on
> > > bpp/lanes and it indeed depends on PLL computation (not tcon_div),
> > > anyway I have explained again on this initial link you mentioned.
> > > Please have a look and get back.
> >
> > I'll have a look, thanks.
> >
> > I've given your patches a try on my setup though, and this patch
> > breaks it with vblank timeouts and some horizontal lines that looks
> > like what should be displayed, but blinking and on the right of the
> > display. The previous ones are fine though.
>
> Would you please send me the link of panel driver.

It's drivers/gpu/drm/panel/panel-ronbo-rb070d30.c

Maximey

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-06-13 12:56               ` Maxime Ripard
@ 2019-06-14  6:33                 ` Jagan Teki
  2019-06-14 14:45                   ` Maxime Ripard
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-06-14  6:33 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Thu, Jun 13, 2019 at 6:56 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Wed, Jun 05, 2019 at 01:17:11PM +0530, Jagan Teki wrote:
> > On Tue, Jun 4, 2019 at 3:30 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > >
> > > On Wed, May 29, 2019 at 11:44:56PM +0530, Jagan Teki wrote:
> > > > On Wed, May 29, 2019 at 8:24 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > >
> > > > > On Fri, May 24, 2019 at 03:48:51PM +0530, Jagan Teki wrote:
> > > > > > On Fri, May 24, 2019 at 2:04 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > >
> > > > > > > On Mon, May 20, 2019 at 02:33:08PM +0530, Jagan Teki wrote:
> > > > > > > > According to "DRM kernel-internal display mode structure" in
> > > > > > > > include/drm/drm_modes.h the current driver is trying to include
> > > > > > > > sync timings along with front porch value while checking and
> > > > > > > > computing drq set bits in non-burst mode.
> > > > > > > >
> > > > > > > > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> > > > > > > >
> > > > > > > > With adding additional sync timings, the dsi controller leads to
> > > > > > > > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > > > > > > > trigger panel flip_done timed out as:
> > > > > > > >
> > > > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > > > >  Modules linked in:
> > > > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
> > > > > > > >  Hardware name: Allwinner sun8i Family
> > > > > > > >  Workqueue: events deferred_probe_work_func
> > > > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > > > >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> > > > > > > >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> > > > > > > >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> > > > > > > >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> > > > > > > >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> > > > > > > >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> > > > > > > >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> > > > > > > >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> > > > > > > >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > > > >  ---[ end trace b57eb1e5c64c6b8b ]---
> > > > > > > >  random: fast init done
> > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > > > > > >
> > > > > > > > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > > > > > > > non-burst DSI mode can be computed based on "horizontal front porch"
> > > > > > > > value only (no sync timings included).
> > > > > > > >
> > > > > > > > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> > > > > > > >
> > > > > > > > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > > > > > > > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > => tt->hor_front_porch - 20
> > > > > > >
> > > > > > > The thing is, while your explanation on the DRM side is sound,
> > > > > > > Allwinner has been using the hbp field of their panel description to
> > > > > > > store what DRM calls the backporch and the sync period.
> > > > > >
> > > > > > Exactly, hbp = backporch + sync
> > > > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046
> > > > > >
> > > > > > And the above computation is rely on that as well. If you can see the
> > > > > > final out of the above computation you can get the front porch value
> > > > > > (w/o sync )
> > > > >
> > > > > As I was saying, you are explaining it well for DRM, but in order for
> > > > > your last formula (the one coming from the BSP) to make sense, you
> > > > > have to explain that the horizontal back porch for Allwinner contains
> > > > > the sync period, otherwise your expansion of lcd_ht doesn't make
> > > > > sense.
> > > >
> > > > I'm not sure why we need to take care of back porch since the formula
> > > > clearly evaluating a result as front porch, without sync timing (as
> > > > current code included this sync), I keep the hbp and trying to
> > > > substitute the lcd_ht value so the end result would cancel hbp.
> > >
> > > Because it changes how lcd_ht expands. In the DRM case, it will expand
> > > to the displayed area, the front porch, the sync period and the back
> > > porch.
> > >
> > > In your case, you expand it to the displayed area, the front porch and
> > > the back porch, precisely because in Allwinner's case, the back porch
> > > has the sync period.
> >
> > I understand the point, but technically it matter about the final
> > computation result.  May be we can even manage the same computation in
> > back porch, but I'm not sure. Since the final output doesn't involve
> > any sync length, why we can include that ie what I'm not sure.
>
> We have the following formula:
> lcd_ht - lcd_x - lcd_hbp - 20
>
> Using the concepts as they are defined in DRM, this expands to:
> x + hbp + hsync + hfp - x - hbp - 20

Here is diff between allwinner hbp vs hbp in DRM.

Say hbp in DRM can call it hbackporch, so

=> x + hbackporch + hsync + hfp - -x - hbp - 20

(and here we need to substitute hbp formula from allwinner since the
actual equation would coming from there
https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046)

=> x + hbackporch + hsync + hfp - x - (hbackporch + hsync) - 20
=> x + hbackporch + hsync + hfp - x - hbackporch - hsync - 20
=> hfp - 20

>
> which ends up as
> hsync + hfp - 20
>
> Now, the same formula with how Allwinner defines it:
> x + hbp + hfp - x - hbp - 20
> which ends up as
> hfp - 20

This is true, and same I have explained in commit log. and hbp here is
as per allwinner so we endedup hfp. which is satisfied by above DRM
equation.

>
> So it definitely matters, and the sync period is used in one but not
> the other.

With the above explanation there is no sync included.

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes
  2019-06-13 13:16           ` Maxime Ripard
@ 2019-06-14 12:03             ` Jagan Teki
  2019-06-24 13:04               ` Maxime Ripard
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-06-14 12:03 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Thu, Jun 13, 2019 at 7:28 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Wed, Jun 05, 2019 at 01:11:44PM +0530, Jagan Teki wrote:
> > On Tue, Jun 4, 2019 at 8:00 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > >
> > > On Fri, May 24, 2019 at 03:37:36PM +0530, Jagan Teki wrote:
> > > > On Fri, May 24, 2019 at 2:18 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > >
> > > > > On Mon, May 20, 2019 at 02:33:11PM +0530, Jagan Teki wrote:
> > > > > > pll-video => pll-mipi => tcon0 => tcon0-pixel-clock is the typical
> > > > > > MIPI clock topology in Allwinner DSI controller.
> > > > > >
> > > > > > TCON dotclock driver is computing the desired DCLK divider based on
> > > > > > panel pixel clock along with input DCLK min, max divider values from
> > > > > > tcon driver and that would eventually set the pll-mipi clock rate.
> > > > > >
> > > > > > The current code is passing dsi min and max divider value as 4 via
> > > > > > tcon driver which would ended-up triggering below vblank wait timed out
> > > > > > warning on "bananapi,s070wv20-ct16" panel.
> > > > > >
> > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > >  Modules linked in:
> > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00025-g5186cdf10757-dirty #6
> > > > > >  Hardware name: Allwinner sun8i Family
> > > > > >  Workqueue: events deferred_probe_work_func
> > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b588>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > >  [<c044b588>] (try_to_bring_up_master) from [<c044b658>] (__component_add+0x94/0x140)
> > > > > >  [<c044b658>] (__component_add) from [<c0445e0c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > >  [<c0445e0c>] (sun6i_dsi_probe) from [<c0452ee4>] (platform_drv_probe+0x48/0x9c)
> > > > > >  [<c0452ee4>] (platform_drv_probe) from [<c04512bc>] (really_probe+0x1dc/0x2c8)
> > > > > >  [<c04512bc>] (really_probe) from [<c0451508>] (driver_probe_device+0x60/0x160)
> > > > > >  [<c0451508>] (driver_probe_device) from [<c044f794>] (bus_for_each_drv+0x74/0xb8)
> > > > > >  [<c044f794>] (bus_for_each_drv) from [<c045106c>] (__device_attach+0xd0/0x13c)
> > > > > >  [<c045106c>] (__device_attach) from [<c0450464>] (bus_probe_device+0x84/0x8c)
> > > > > >  [<c0450464>] (bus_probe_device) from [<c04508f0>] (deferred_probe_work_func+0x64/0x90)
> > > > > >  [<c04508f0>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > >  ---[ end trace 4017fea4906ab391 ]---
> > > > > >
> > > > > > But accordingly to Allwinner A33, A64 BSP codes [1] [2] this divider
> > > > > > is clearly using 'format/lanes' for dsi divider value, dsi_clk.clk_div
> > > > > >
> > > > > > Which would compute the pll_freq and set a clock rate for it in
> > > > > > [3] and [4] respectively.
> > > > > >
> > > > > > The same issue has reproduced in A33, A64 with 4-lane and 2-lane devices
> > > > > > and got fixed with this computation logic 'format/lanes', so this patch
> > > > > > using dclk min and max dividers as per BSP.
> > > > > >
> > > > > > [1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1106
> > > > > > [2] https://github.com/BPI-SINOVOIP/BPI-M64-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/disp_al.c#L213
> > > > > > [3] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1127
> > > > > > [4] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1161
> > > > >
> > > > > In that mail, I've pointed out that clk_div isn't used for the TCON dclk divider:
> > > > > http://lists.infradead.org/pipermail/linux-arm-kernel/2019-February/629596.html
> > > > >
> > > > > The only reply you've sent is that you indeed see that the divider is
> > > > > set to 4 in the BSP, but you're now saying that the BSP can change
> > > > > it. If so, then please point exactly the flaw in the explanation in
> > > > > that mail.
> > > >
> > > > Frankly, I have explained these details in commit message and previous
> > > > version patch[1] with print messages on the code.
> > > >
> > > > BSP has tcon_div and dsi_div. dsi_div is dynamic which depends on
> > > > bpp/lanes and it indeed depends on PLL computation (not tcon_div),
> > > > anyway I have explained again on this initial link you mentioned.
> > > > Please have a look and get back.
> > >
> > > I'll have a look, thanks.
> > >
> > > I've given your patches a try on my setup though, and this patch
> > > breaks it with vblank timeouts and some horizontal lines that looks
> > > like what should be displayed, but blinking and on the right of the
> > > display. The previous ones are fine though.
> >
> > Would you please send me the link of panel driver.
>
> It's drivers/gpu/drm/panel/panel-ronbo-rb070d30.c

Look like this panel work even w/o any vendor sequence. it's similar
to the 4-lane panel I have with RGB888, so the dclk div is 6, is it
working with this divider?

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 02/11] drm/sun4i: dsi: Update start value in video start delay
  2019-06-13  8:04         ` Jagan Teki
@ 2019-06-14 14:28           ` Maxime Ripard
  2019-06-18 11:02             ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-06-14 14:28 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

[-- Attachment #1.1: Type: text/plain, Size: 8913 bytes --]

On Thu, Jun 13, 2019 at 01:34:04PM +0530, Jagan Teki wrote:
> On Fri, May 31, 2019 at 12:23 AM Maxime Ripard
> <maxime.ripard@bootlin.com> wrote:
> >
> > On Fri, May 24, 2019 at 03:55:42PM +0530, Jagan Teki wrote:
> > > On Fri, May 24, 2019 at 2:07 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > >
> > > > On Mon, May 20, 2019 at 02:33:09PM +0530, Jagan Teki wrote:
> > > > > start value in video start delay computation done in below commit
> > > > > is as per the legacy bsp drivers/video/sunxi/legacy..
> > > > > "drm/sun4i: dsi: Change the start delay calculation"
> > > > > (sha1: da676c6aa6413d59ab0a80c97bbc273025e640b2)
> > > > >
> > > > > This existing start delay computation gives start value of 35,
> > > > > for "bananapi,s070wv20-ct16" panel timings which indeed trigger
> > > > > panel flip_done timed out as:
> > > > >
> > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > >  Modules linked in:
> > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Tainted: G        W         5.1.0-next-20190514-00025-gf928bc7cc146 #15
> > > > >  Hardware name: Allwinner sun8i Family
> > > > >  Workqueue: events deferred_probe_work_func
> > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > >  [<c010b76c>] (show_stack) from [<c0688c90>] (dump_stack+0x84/0x98)
> > > > >  [<c0688c90>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c0411cb0>] (drm_fb_helper_pan_display+0xac/0x1d0)
> > > > >  [<c0411cb0>] (drm_fb_helper_pan_display) from [<c03a4e84>] (fb_pan_display+0xcc/0x134)
> > > > >  [<c03a4e84>] (fb_pan_display) from [<c03b1214>] (bit_update_start+0x14/0x30)
> > > > >  [<c03b1214>] (bit_update_start) from [<c03afe94>] (fbcon_switch+0x3d8/0x4e0)
> > > > >  [<c03afe94>] (fbcon_switch) from [<c03ec930>] (redraw_screen+0x174/0x238)
> > > > >  [<c03ec930>] (redraw_screen) from [<c03aceb4>] (fbcon_prepare_logo+0x3c4/0x400)
> > > > >  [<c03aceb4>] (fbcon_prepare_logo) from [<c03ad2b8>] (fbcon_init+0x3c8/0x5ac)
> > > > >  [<c03ad2b8>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b5b0>] (try_to_bring_up_master+0x164/0x1a0)
> > > > >  [<c044b5b0>] (try_to_bring_up_master) from [<c044b680>] (__component_add+0x94/0x140)
> > > > >  [<c044b680>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452f0c>] (platform_drv_probe+0x48/0x9c)
> > > > >  [<c0452f0c>] (platform_drv_probe) from [<c04512e4>] (really_probe+0x1dc/0x2c8)
> > > > >  [<c04512e4>] (really_probe) from [<c0451530>] (driver_probe_device+0x60/0x160)
> > > > >  [<c0451530>] (driver_probe_device) from [<c044f7bc>] (bus_for_each_drv+0x74/0xb8)
> > > > >  [<c044f7bc>] (bus_for_each_drv) from [<c0451094>] (__device_attach+0xd0/0x13c)
> > > > >  [<c0451094>] (__device_attach) from [<c045048c>] (bus_probe_device+0x84/0x8c)
> > > > >  [<c045048c>] (bus_probe_device) from [<c0450918>] (deferred_probe_work_func+0x64/0x90)
> > > > >  [<c0450918>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > >  ---[ end trace 755e10f62b83f396 ]---
> > > > >  Console: switching to colour frame buffer device 100x30
> > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > > >
> > > > > But the expected start delay value is 1 which is confirmed from
> > > > > new bsp [2].
> > > >
> > > > If you're saying that the "legacy" link (second one) is the new BSP.
> > >
> > > Will update, thanks.
> > >
> > > >
> > > > > The important and unclear note on legacy and new bsp codes [1] [2]
> > > > > is both use similar start computation initially but it later reassign
> > > > > it to 1 in new bsp.
> > > >
> > > > Then start_delay is never reassigned to 1 in that link, and is clamped
> > > > between 8 and 100 as the code that you are removing is doing.
> > >
> > > Please see the link one more please
> > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L807
> > >
> > > >
> > > > > Unfortunately we don't have any evidence or documentation for this
> > > > > reassignment to 1 in new bsp, but it is working with all supported
> > > > > panels in A33, A64.
> > > >
> > > > No, it's not. That was added to fix a panel that is supported today.
> > >
> > > No, I have see this in A33, A64. and these are controller drivers
> > > right, if it panel fix and it should be part of panel driver isn't
> > > it?
> >
> > I'm not sure to follow that argument. You're submitting that fix to
> > allow other panels to work, right? So surely, some issues that can be
> > found using a given panel might not be solely fixed in the panel driver.
>
> I'm not sure I understand this. I have been verifying different panels
> to check across. and this change literally in BSP and the BSP code is
> using this based on the logs confirmation. all the logs and working
> conditions shows that the fix would required in dsi.

You were saying that your fix was working with all supported panels in
A33, A64. That's simply not true, since at least one of mine will be
broken by this.

You can say that it fixes all the panels *you* have, but it's
certainly not all of them.

> > > We can even see the same in pin64 longsleep kernel and others.
> > >
> > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L807
> > > https://github.com/longsleep/linux-pine64/blob/pine64-hacks-1.2/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/de_dsi.c#L730
> >
> > Yeah, and both of these have the legacy driver part with the clamping
> > too.
>
> Yes, both legacy has clamping, but not using.

See the links above, they are being used.

> they used it in new version driver which I'm referring above.

I'm sorry, but I just don't get what you're saying. The links
mentionned above are clearly showing that it's being used, while the
other, !legacy, driver doesn't have them anymore. So it seems to be
exactly the opposite of what you're saying.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-06-14  6:33                 ` Jagan Teki
@ 2019-06-14 14:45                   ` Maxime Ripard
  2019-06-18 10:51                     ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-06-14 14:45 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

[-- Attachment #1.1: Type: text/plain, Size: 10083 bytes --]

On Fri, Jun 14, 2019 at 12:03:13PM +0530, Jagan Teki wrote:
> On Thu, Jun 13, 2019 at 6:56 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> >
> > On Wed, Jun 05, 2019 at 01:17:11PM +0530, Jagan Teki wrote:
> > > On Tue, Jun 4, 2019 at 3:30 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > >
> > > > On Wed, May 29, 2019 at 11:44:56PM +0530, Jagan Teki wrote:
> > > > > On Wed, May 29, 2019 at 8:24 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > >
> > > > > > On Fri, May 24, 2019 at 03:48:51PM +0530, Jagan Teki wrote:
> > > > > > > On Fri, May 24, 2019 at 2:04 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > >
> > > > > > > > On Mon, May 20, 2019 at 02:33:08PM +0530, Jagan Teki wrote:
> > > > > > > > > According to "DRM kernel-internal display mode structure" in
> > > > > > > > > include/drm/drm_modes.h the current driver is trying to include
> > > > > > > > > sync timings along with front porch value while checking and
> > > > > > > > > computing drq set bits in non-burst mode.
> > > > > > > > >
> > > > > > > > > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> > > > > > > > >
> > > > > > > > > With adding additional sync timings, the dsi controller leads to
> > > > > > > > > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > > > > > > > > trigger panel flip_done timed out as:
> > > > > > > > >
> > > > > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > > > > >  Modules linked in:
> > > > > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
> > > > > > > > >  Hardware name: Allwinner sun8i Family
> > > > > > > > >  Workqueue: events deferred_probe_work_func
> > > > > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > > > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > > > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > > > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > > > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > > > > >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> > > > > > > > >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > > > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> > > > > > > > >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> > > > > > > > >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> > > > > > > > >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> > > > > > > > >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> > > > > > > > >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> > > > > > > > >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> > > > > > > > >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > > > > >  ---[ end trace b57eb1e5c64c6b8b ]---
> > > > > > > > >  random: fast init done
> > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > > > > > > >
> > > > > > > > > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > > > > > > > > non-burst DSI mode can be computed based on "horizontal front porch"
> > > > > > > > > value only (no sync timings included).
> > > > > > > > >
> > > > > > > > > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> > > > > > > > >
> > > > > > > > > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > > > > > > > > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > > => tt->hor_front_porch - 20
> > > > > > > >
> > > > > > > > The thing is, while your explanation on the DRM side is sound,
> > > > > > > > Allwinner has been using the hbp field of their panel description to
> > > > > > > > store what DRM calls the backporch and the sync period.
> > > > > > >
> > > > > > > Exactly, hbp = backporch + sync
> > > > > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046
> > > > > > >
> > > > > > > And the above computation is rely on that as well. If you can see the
> > > > > > > final out of the above computation you can get the front porch value
> > > > > > > (w/o sync )
> > > > > >
> > > > > > As I was saying, you are explaining it well for DRM, but in order for
> > > > > > your last formula (the one coming from the BSP) to make sense, you
> > > > > > have to explain that the horizontal back porch for Allwinner contains
> > > > > > the sync period, otherwise your expansion of lcd_ht doesn't make
> > > > > > sense.
> > > > >
> > > > > I'm not sure why we need to take care of back porch since the formula
> > > > > clearly evaluating a result as front porch, without sync timing (as
> > > > > current code included this sync), I keep the hbp and trying to
> > > > > substitute the lcd_ht value so the end result would cancel hbp.
> > > >
> > > > Because it changes how lcd_ht expands. In the DRM case, it will expand
> > > > to the displayed area, the front porch, the sync period and the back
> > > > porch.
> > > >
> > > > In your case, you expand it to the displayed area, the front porch and
> > > > the back porch, precisely because in Allwinner's case, the back porch
> > > > has the sync period.
> > >
> > > I understand the point, but technically it matter about the final
> > > computation result.  May be we can even manage the same computation in
> > > back porch, but I'm not sure. Since the final output doesn't involve
> > > any sync length, why we can include that ie what I'm not sure.
> >
> > We have the following formula:
> > lcd_ht - lcd_x - lcd_hbp - 20
> >
> > Using the concepts as they are defined in DRM, this expands to:
> > x + hbp + hsync + hfp - x - hbp - 20
>
> Here is diff between allwinner hbp vs hbp in DRM.
>
> Say hbp in DRM can call it hbackporch, so
>
> => x + hbackporch + hsync + hfp - -x - hbp - 20
>
> (and here we need to substitute hbp formula from allwinner since the
> actual equation would coming from there
> https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046)

And this is precisely what needs to be said, with an explanation about
where that hor_back_porch is being used later on, and what impact it
could have.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-06-14 14:45                   ` Maxime Ripard
@ 2019-06-18 10:51                     ` Jagan Teki
  2019-06-18 11:43                       ` [linux-sunxi] " Chen-Yu Tsai
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-06-18 10:51 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Fri, Jun 14, 2019 at 8:15 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Fri, Jun 14, 2019 at 12:03:13PM +0530, Jagan Teki wrote:
> > On Thu, Jun 13, 2019 at 6:56 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > >
> > > On Wed, Jun 05, 2019 at 01:17:11PM +0530, Jagan Teki wrote:
> > > > On Tue, Jun 4, 2019 at 3:30 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > >
> > > > > On Wed, May 29, 2019 at 11:44:56PM +0530, Jagan Teki wrote:
> > > > > > On Wed, May 29, 2019 at 8:24 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > >
> > > > > > > On Fri, May 24, 2019 at 03:48:51PM +0530, Jagan Teki wrote:
> > > > > > > > On Fri, May 24, 2019 at 2:04 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > >
> > > > > > > > > On Mon, May 20, 2019 at 02:33:08PM +0530, Jagan Teki wrote:
> > > > > > > > > > According to "DRM kernel-internal display mode structure" in
> > > > > > > > > > include/drm/drm_modes.h the current driver is trying to include
> > > > > > > > > > sync timings along with front porch value while checking and
> > > > > > > > > > computing drq set bits in non-burst mode.
> > > > > > > > > >
> > > > > > > > > > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> > > > > > > > > >
> > > > > > > > > > With adding additional sync timings, the dsi controller leads to
> > > > > > > > > > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > > > > > > > > > trigger panel flip_done timed out as:
> > > > > > > > > >
> > > > > > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > > > > > >  Modules linked in:
> > > > > > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
> > > > > > > > > >  Hardware name: Allwinner sun8i Family
> > > > > > > > > >  Workqueue: events deferred_probe_work_func
> > > > > > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > > > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > > > > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > > > > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > > > > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > > > > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > > > > > >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> > > > > > > > > >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > > > > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> > > > > > > > > >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> > > > > > > > > >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> > > > > > > > > >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> > > > > > > > > >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> > > > > > > > > >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> > > > > > > > > >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> > > > > > > > > >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > > > > > >  ---[ end trace b57eb1e5c64c6b8b ]---
> > > > > > > > > >  random: fast init done
> > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > > > > > > > >
> > > > > > > > > > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > > > > > > > > > non-burst DSI mode can be computed based on "horizontal front porch"
> > > > > > > > > > value only (no sync timings included).
> > > > > > > > > >
> > > > > > > > > > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> > > > > > > > > >
> > > > > > > > > > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > > > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > > > > > > > > > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > > > => tt->hor_front_porch - 20
> > > > > > > > >
> > > > > > > > > The thing is, while your explanation on the DRM side is sound,
> > > > > > > > > Allwinner has been using the hbp field of their panel description to
> > > > > > > > > store what DRM calls the backporch and the sync period.
> > > > > > > >
> > > > > > > > Exactly, hbp = backporch + sync
> > > > > > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046
> > > > > > > >
> > > > > > > > And the above computation is rely on that as well. If you can see the
> > > > > > > > final out of the above computation you can get the front porch value
> > > > > > > > (w/o sync )
> > > > > > >
> > > > > > > As I was saying, you are explaining it well for DRM, but in order for
> > > > > > > your last formula (the one coming from the BSP) to make sense, you
> > > > > > > have to explain that the horizontal back porch for Allwinner contains
> > > > > > > the sync period, otherwise your expansion of lcd_ht doesn't make
> > > > > > > sense.
> > > > > >
> > > > > > I'm not sure why we need to take care of back porch since the formula
> > > > > > clearly evaluating a result as front porch, without sync timing (as
> > > > > > current code included this sync), I keep the hbp and trying to
> > > > > > substitute the lcd_ht value so the end result would cancel hbp.
> > > > >
> > > > > Because it changes how lcd_ht expands. In the DRM case, it will expand
> > > > > to the displayed area, the front porch, the sync period and the back
> > > > > porch.
> > > > >
> > > > > In your case, you expand it to the displayed area, the front porch and
> > > > > the back porch, precisely because in Allwinner's case, the back porch
> > > > > has the sync period.
> > > >
> > > > I understand the point, but technically it matter about the final
> > > > computation result.  May be we can even manage the same computation in
> > > > back porch, but I'm not sure. Since the final output doesn't involve
> > > > any sync length, why we can include that ie what I'm not sure.
> > >
> > > We have the following formula:
> > > lcd_ht - lcd_x - lcd_hbp - 20
> > >
> > > Using the concepts as they are defined in DRM, this expands to:
> > > x + hbp + hsync + hfp - x - hbp - 20
> >
> > Here is diff between allwinner hbp vs hbp in DRM.
> >
> > Say hbp in DRM can call it hbackporch, so
> >
> > => x + hbackporch + hsync + hfp - -x - hbp - 20
> >
> > (and here we need to substitute hbp formula from allwinner since the
> > actual equation would coming from there
> > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046)
>
> And this is precisely what needs to be said, with an explanation about
> where that hor_back_porch is being used later on, and what impact it
> could have.

Yes, it an equation and the mathematical equations can be substitute
to variety kind I did agree with that, whether you can use hbackporch
or not or use another-way the final resulting value is equivalent to
the value of front porch. In that case we can solve based on what I
explained above. If you still dought me, please run BSP and check the
resulting value on this check, you can get the front porch value.

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http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 02/11] drm/sun4i: dsi: Update start value in video start delay
  2019-06-14 14:28           ` Maxime Ripard
@ 2019-06-18 11:02             ` Jagan Teki
  0 siblings, 0 replies; 54+ messages in thread
From: Jagan Teki @ 2019-06-18 11:02 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Fri, Jun 14, 2019 at 7:58 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Thu, Jun 13, 2019 at 01:34:04PM +0530, Jagan Teki wrote:
> > On Fri, May 31, 2019 at 12:23 AM Maxime Ripard
> > <maxime.ripard@bootlin.com> wrote:
> > >
> > > On Fri, May 24, 2019 at 03:55:42PM +0530, Jagan Teki wrote:
> > > > On Fri, May 24, 2019 at 2:07 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > >
> > > > > On Mon, May 20, 2019 at 02:33:09PM +0530, Jagan Teki wrote:
> > > > > > start value in video start delay computation done in below commit
> > > > > > is as per the legacy bsp drivers/video/sunxi/legacy..
> > > > > > "drm/sun4i: dsi: Change the start delay calculation"
> > > > > > (sha1: da676c6aa6413d59ab0a80c97bbc273025e640b2)
> > > > > >
> > > > > > This existing start delay computation gives start value of 35,
> > > > > > for "bananapi,s070wv20-ct16" panel timings which indeed trigger
> > > > > > panel flip_done timed out as:
> > > > > >
> > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > >  Modules linked in:
> > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Tainted: G        W         5.1.0-next-20190514-00025-gf928bc7cc146 #15
> > > > > >  Hardware name: Allwinner sun8i Family
> > > > > >  Workqueue: events deferred_probe_work_func
> > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > >  [<c010b76c>] (show_stack) from [<c0688c90>] (dump_stack+0x84/0x98)
> > > > > >  [<c0688c90>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c0411cb0>] (drm_fb_helper_pan_display+0xac/0x1d0)
> > > > > >  [<c0411cb0>] (drm_fb_helper_pan_display) from [<c03a4e84>] (fb_pan_display+0xcc/0x134)
> > > > > >  [<c03a4e84>] (fb_pan_display) from [<c03b1214>] (bit_update_start+0x14/0x30)
> > > > > >  [<c03b1214>] (bit_update_start) from [<c03afe94>] (fbcon_switch+0x3d8/0x4e0)
> > > > > >  [<c03afe94>] (fbcon_switch) from [<c03ec930>] (redraw_screen+0x174/0x238)
> > > > > >  [<c03ec930>] (redraw_screen) from [<c03aceb4>] (fbcon_prepare_logo+0x3c4/0x400)
> > > > > >  [<c03aceb4>] (fbcon_prepare_logo) from [<c03ad2b8>] (fbcon_init+0x3c8/0x5ac)
> > > > > >  [<c03ad2b8>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b5b0>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > >  [<c044b5b0>] (try_to_bring_up_master) from [<c044b680>] (__component_add+0x94/0x140)
> > > > > >  [<c044b680>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452f0c>] (platform_drv_probe+0x48/0x9c)
> > > > > >  [<c0452f0c>] (platform_drv_probe) from [<c04512e4>] (really_probe+0x1dc/0x2c8)
> > > > > >  [<c04512e4>] (really_probe) from [<c0451530>] (driver_probe_device+0x60/0x160)
> > > > > >  [<c0451530>] (driver_probe_device) from [<c044f7bc>] (bus_for_each_drv+0x74/0xb8)
> > > > > >  [<c044f7bc>] (bus_for_each_drv) from [<c0451094>] (__device_attach+0xd0/0x13c)
> > > > > >  [<c0451094>] (__device_attach) from [<c045048c>] (bus_probe_device+0x84/0x8c)
> > > > > >  [<c045048c>] (bus_probe_device) from [<c0450918>] (deferred_probe_work_func+0x64/0x90)
> > > > > >  [<c0450918>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > >  ---[ end trace 755e10f62b83f396 ]---
> > > > > >  Console: switching to colour frame buffer device 100x30
> > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > > > >
> > > > > > But the expected start delay value is 1 which is confirmed from
> > > > > > new bsp [2].
> > > > >
> > > > > If you're saying that the "legacy" link (second one) is the new BSP.
> > > >
> > > > Will update, thanks.
> > > >
> > > > >
> > > > > > The important and unclear note on legacy and new bsp codes [1] [2]
> > > > > > is both use similar start computation initially but it later reassign
> > > > > > it to 1 in new bsp.
> > > > >
> > > > > Then start_delay is never reassigned to 1 in that link, and is clamped
> > > > > between 8 and 100 as the code that you are removing is doing.
> > > >
> > > > Please see the link one more please
> > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L807
> > > >
> > > > >
> > > > > > Unfortunately we don't have any evidence or documentation for this
> > > > > > reassignment to 1 in new bsp, but it is working with all supported
> > > > > > panels in A33, A64.
> > > > >
> > > > > No, it's not. That was added to fix a panel that is supported today.
> > > >
> > > > No, I have see this in A33, A64. and these are controller drivers
> > > > right, if it panel fix and it should be part of panel driver isn't
> > > > it?
> > >
> > > I'm not sure to follow that argument. You're submitting that fix to
> > > allow other panels to work, right? So surely, some issues that can be
> > > found using a given panel might not be solely fixed in the panel driver.
> >
> > I'm not sure I understand this. I have been verifying different panels
> > to check across. and this change literally in BSP and the BSP code is
> > using this based on the logs confirmation. all the logs and working
> > conditions shows that the fix would required in dsi.
>
> You were saying that your fix was working with all supported panels in
> A33, A64. That's simply not true, since at least one of mine will be
> broken by this.
>
> You can say that it fixes all the panels *you* have, but it's
> certainly not all of them.

The panels I have are running A33, A64 AW BSP and there are not using
legacy drivers. better you can use what AW BSP's are using, if
something not working with AW bsp then there can be an issue on the
panel init sequence or timings.

>
> > > > We can even see the same in pin64 longsleep kernel and others.
> > > >
> > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L807
> > > > https://github.com/longsleep/linux-pine64/blob/pine64-hacks-1.2/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/de_dsi.c#L730
> > >
> > > Yeah, and both of these have the legacy driver part with the clamping
> > > too.
> >
> > Yes, both legacy has clamping, but not using.
>
> See the links above, they are being used.
>
> > they used it in new version driver which I'm referring above.
>
> I'm sorry, but I just don't get what you're saying. The links
> mentionned above are clearly showing that it's being used, while the
> other, !legacy, driver doesn't have them anymore. So it seems to be
> exactly the opposite of what you're saying.

legacy drivers have the clamping of what the current code has, I agree
that point. but the new version BSP driver which is running on right
now, don't have clamping instead they do have a change what this patch
has.

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-06-18 10:51                     ` Jagan Teki
@ 2019-06-18 11:43                       ` " Chen-Yu Tsai
  2019-06-18 12:11                         ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Chen-Yu Tsai @ 2019-06-18 11:43 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, 坚定前行,
	Maxime Ripard, linux-kernel, dri-devel, David Airlie,
	linux-sunxi, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Tue, Jun 18, 2019 at 6:51 PM Jagan Teki <jagan@amarulasolutions.com> wrote:
>
> On Fri, Jun 14, 2019 at 8:15 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> >
> > On Fri, Jun 14, 2019 at 12:03:13PM +0530, Jagan Teki wrote:
> > > On Thu, Jun 13, 2019 at 6:56 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > >
> > > > On Wed, Jun 05, 2019 at 01:17:11PM +0530, Jagan Teki wrote:
> > > > > On Tue, Jun 4, 2019 at 3:30 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > >
> > > > > > On Wed, May 29, 2019 at 11:44:56PM +0530, Jagan Teki wrote:
> > > > > > > On Wed, May 29, 2019 at 8:24 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > >
> > > > > > > > On Fri, May 24, 2019 at 03:48:51PM +0530, Jagan Teki wrote:
> > > > > > > > > On Fri, May 24, 2019 at 2:04 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > > >
> > > > > > > > > > On Mon, May 20, 2019 at 02:33:08PM +0530, Jagan Teki wrote:
> > > > > > > > > > > According to "DRM kernel-internal display mode structure" in
> > > > > > > > > > > include/drm/drm_modes.h the current driver is trying to include
> > > > > > > > > > > sync timings along with front porch value while checking and
> > > > > > > > > > > computing drq set bits in non-burst mode.
> > > > > > > > > > >
> > > > > > > > > > > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> > > > > > > > > > >
> > > > > > > > > > > With adding additional sync timings, the dsi controller leads to
> > > > > > > > > > > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > > > > > > > > > > trigger panel flip_done timed out as:
> > > > > > > > > > >
> > > > > > > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > > > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > > > > > > >  Modules linked in:
> > > > > > > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
> > > > > > > > > > >  Hardware name: Allwinner sun8i Family
> > > > > > > > > > >  Workqueue: events deferred_probe_work_func
> > > > > > > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > > > > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > > > > > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > > > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > > > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > > > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > > > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > > > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > > > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > > > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > > > > > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > > > > > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > > > > > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > > > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > > > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > > > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > > > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > > > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > > > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > > > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > > > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > > > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > > > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > > > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > > > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > > > > > > >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> > > > > > > > > > >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > > > > > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> > > > > > > > > > >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> > > > > > > > > > >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> > > > > > > > > > >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> > > > > > > > > > >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> > > > > > > > > > >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> > > > > > > > > > >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> > > > > > > > > > >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > > > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > > > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > > > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > > > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > > > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > > > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > > > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > > > > > > >  ---[ end trace b57eb1e5c64c6b8b ]---
> > > > > > > > > > >  random: fast init done
> > > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > > > > > > > > >
> > > > > > > > > > > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > > > > > > > > > > non-burst DSI mode can be computed based on "horizontal front porch"
> > > > > > > > > > > value only (no sync timings included).
> > > > > > > > > > >
> > > > > > > > > > > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> > > > > > > > > > >
> > > > > > > > > > > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > > > > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > > > > > > > > > > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > > > > => tt->hor_front_porch - 20
> > > > > > > > > >
> > > > > > > > > > The thing is, while your explanation on the DRM side is sound,
> > > > > > > > > > Allwinner has been using the hbp field of their panel description to
> > > > > > > > > > store what DRM calls the backporch and the sync period.
> > > > > > > > >
> > > > > > > > > Exactly, hbp = backporch + sync
> > > > > > > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046
> > > > > > > > >
> > > > > > > > > And the above computation is rely on that as well. If you can see the
> > > > > > > > > final out of the above computation you can get the front porch value
> > > > > > > > > (w/o sync )
> > > > > > > >
> > > > > > > > As I was saying, you are explaining it well for DRM, but in order for
> > > > > > > > your last formula (the one coming from the BSP) to make sense, you
> > > > > > > > have to explain that the horizontal back porch for Allwinner contains
> > > > > > > > the sync period, otherwise your expansion of lcd_ht doesn't make
> > > > > > > > sense.
> > > > > > >
> > > > > > > I'm not sure why we need to take care of back porch since the formula
> > > > > > > clearly evaluating a result as front porch, without sync timing (as
> > > > > > > current code included this sync), I keep the hbp and trying to
> > > > > > > substitute the lcd_ht value so the end result would cancel hbp.
> > > > > >
> > > > > > Because it changes how lcd_ht expands. In the DRM case, it will expand
> > > > > > to the displayed area, the front porch, the sync period and the back
> > > > > > porch.
> > > > > >
> > > > > > In your case, you expand it to the displayed area, the front porch and
> > > > > > the back porch, precisely because in Allwinner's case, the back porch
> > > > > > has the sync period.
> > > > >
> > > > > I understand the point, but technically it matter about the final
> > > > > computation result.  May be we can even manage the same computation in
> > > > > back porch, but I'm not sure. Since the final output doesn't involve
> > > > > any sync length, why we can include that ie what I'm not sure.
> > > >
> > > > We have the following formula:
> > > > lcd_ht - lcd_x - lcd_hbp - 20
> > > >
> > > > Using the concepts as they are defined in DRM, this expands to:
> > > > x + hbp + hsync + hfp - x - hbp - 20
> > >
> > > Here is diff between allwinner hbp vs hbp in DRM.
> > >
> > > Say hbp in DRM can call it hbackporch, so
> > >
> > > => x + hbackporch + hsync + hfp - -x - hbp - 20
> > >
> > > (and here we need to substitute hbp formula from allwinner since the
> > > actual equation would coming from there
> > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046)
> >
> > And this is precisely what needs to be said, with an explanation about
> > where that hor_back_porch is being used later on, and what impact it
> > could have.
>
> Yes, it an equation and the mathematical equations can be substitute
> to variety kind I did agree with that, whether you can use hbackporch
> or not or use another-way the final resulting value is equivalent to
> the value of front porch. In that case we can solve based on what I
> explained above. If you still dought me, please run BSP and check the
> resulting value on this check, you can get the front porch value.

Maxime is not doubting you. He is saying that you need to include the
detailed explanation in your commit log, and not just reference pieces
of code. This is separate from the requirement of having a correct patch.

Providing just a mathematical formula isn't enough either, because it
is not clear to the average reader which term expanded into what. A
better way to do is to first provide the definition of each term in
a form easy to understand, such as the following:

    List of LCD parameters as defined by Allwinner, explained using terms
    from the DRM subsystem:

      - lcd_ht: horizontal total size
      - lcd_x: horizontal display size
      - lcd_hbp: horizontal sync + backporch

Or better yet, copy the diagram from drm_modes.h and add lcd_* to the bottom
to show the differences.

    <-------------------------------- lcd_[hv]t ----------------------------->
    <----- lcd_[xy] -------->                  <-------- lcd_[hv]bp --------->

             Active                 Front           Sync           Back
             Region                 Porch                          Porch
    <-----------------------><----------------><-------------><-------------->
      //////////////////////|
     ////////////////////// |
    //////////////////////  |..................               ................
                                               _______________
    <----- [hv]display ----->
    <------------- [hv]sync_start ------------>
    <--------------------- [hv]sync_end --------------------->
    <-------------------------------- [hv]total ----------------------------->


Then you can go on explain what effect the difference in the definition of
"backporch" has on the piece of code you are fixing:

    The DSI driver misinterpreted the hbp term from the BSP code to refer
    only to the backporch, when in fact it was backporch + sync. Thus the
    driver incorrectly used the horizontal front porch plus sync in its
    calculation of the DRQ value, when it should not have included the sync
    period.

The above explains how you came to create your fix. At this point you don't
even need to include the mathematical formulas anymore.

The why you already explained, the flip_done time outs. The result you haven't
explained, but it can be as simple as:

    With the terms fixed, the panel displays correctly without any timeouts.

Hope this explains clearly what is needed in your commit log, and how to make
it easier to understand for other, especially for people either not familiar
with display internals, and/or Allwinner specifics.

Regards
ChenYu

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-06-18 11:43                       ` [linux-sunxi] " Chen-Yu Tsai
@ 2019-06-18 12:11                         ` Jagan Teki
  2019-06-18 14:45                           ` Chen-Yu Tsai
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-06-18 12:11 UTC (permalink / raw)
  To: Chen-Yu Tsai
  Cc: Bhushan Shah, 坚定前行,
	Maxime Ripard, linux-kernel, dri-devel, David Airlie,
	linux-sunxi, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Tue, Jun 18, 2019 at 5:13 PM Chen-Yu Tsai <wens@csie.org> wrote:
>
> On Tue, Jun 18, 2019 at 6:51 PM Jagan Teki <jagan@amarulasolutions.com> wrote:
> >
> > On Fri, Jun 14, 2019 at 8:15 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > >
> > > On Fri, Jun 14, 2019 at 12:03:13PM +0530, Jagan Teki wrote:
> > > > On Thu, Jun 13, 2019 at 6:56 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > >
> > > > > On Wed, Jun 05, 2019 at 01:17:11PM +0530, Jagan Teki wrote:
> > > > > > On Tue, Jun 4, 2019 at 3:30 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > >
> > > > > > > On Wed, May 29, 2019 at 11:44:56PM +0530, Jagan Teki wrote:
> > > > > > > > On Wed, May 29, 2019 at 8:24 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > >
> > > > > > > > > On Fri, May 24, 2019 at 03:48:51PM +0530, Jagan Teki wrote:
> > > > > > > > > > On Fri, May 24, 2019 at 2:04 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > > > >
> > > > > > > > > > > On Mon, May 20, 2019 at 02:33:08PM +0530, Jagan Teki wrote:
> > > > > > > > > > > > According to "DRM kernel-internal display mode structure" in
> > > > > > > > > > > > include/drm/drm_modes.h the current driver is trying to include
> > > > > > > > > > > > sync timings along with front porch value while checking and
> > > > > > > > > > > > computing drq set bits in non-burst mode.
> > > > > > > > > > > >
> > > > > > > > > > > > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> > > > > > > > > > > >
> > > > > > > > > > > > With adding additional sync timings, the dsi controller leads to
> > > > > > > > > > > > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > > > > > > > > > > > trigger panel flip_done timed out as:
> > > > > > > > > > > >
> > > > > > > > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > > > > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > > > > > > > >  Modules linked in:
> > > > > > > > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
> > > > > > > > > > > >  Hardware name: Allwinner sun8i Family
> > > > > > > > > > > >  Workqueue: events deferred_probe_work_func
> > > > > > > > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > > > > > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > > > > > > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > > > > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > > > > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > > > > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > > > > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > > > > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > > > > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > > > > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > > > > > > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > > > > > > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > > > > > > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > > > > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > > > > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > > > > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > > > > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > > > > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > > > > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > > > > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > > > > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > > > > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > > > > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > > > > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > > > > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > > > > > > > >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> > > > > > > > > > > >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > > > > > > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> > > > > > > > > > > >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> > > > > > > > > > > >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> > > > > > > > > > > >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> > > > > > > > > > > >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> > > > > > > > > > > >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> > > > > > > > > > > >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> > > > > > > > > > > >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > > > > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > > > > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > > > > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > > > > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > > > > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > > > > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > > > > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > > > > > > > >  ---[ end trace b57eb1e5c64c6b8b ]---
> > > > > > > > > > > >  random: fast init done
> > > > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > > > > > > > > > >
> > > > > > > > > > > > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > > > > > > > > > > > non-burst DSI mode can be computed based on "horizontal front porch"
> > > > > > > > > > > > value only (no sync timings included).
> > > > > > > > > > > >
> > > > > > > > > > > > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> > > > > > > > > > > >
> > > > > > > > > > > > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > > > > > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > > > > > > > > > > > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > > > > > => tt->hor_front_porch - 20
> > > > > > > > > > >
> > > > > > > > > > > The thing is, while your explanation on the DRM side is sound,
> > > > > > > > > > > Allwinner has been using the hbp field of their panel description to
> > > > > > > > > > > store what DRM calls the backporch and the sync period.
> > > > > > > > > >
> > > > > > > > > > Exactly, hbp = backporch + sync
> > > > > > > > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046
> > > > > > > > > >
> > > > > > > > > > And the above computation is rely on that as well. If you can see the
> > > > > > > > > > final out of the above computation you can get the front porch value
> > > > > > > > > > (w/o sync )
> > > > > > > > >
> > > > > > > > > As I was saying, you are explaining it well for DRM, but in order for
> > > > > > > > > your last formula (the one coming from the BSP) to make sense, you
> > > > > > > > > have to explain that the horizontal back porch for Allwinner contains
> > > > > > > > > the sync period, otherwise your expansion of lcd_ht doesn't make
> > > > > > > > > sense.
> > > > > > > >
> > > > > > > > I'm not sure why we need to take care of back porch since the formula
> > > > > > > > clearly evaluating a result as front porch, without sync timing (as
> > > > > > > > current code included this sync), I keep the hbp and trying to
> > > > > > > > substitute the lcd_ht value so the end result would cancel hbp.
> > > > > > >
> > > > > > > Because it changes how lcd_ht expands. In the DRM case, it will expand
> > > > > > > to the displayed area, the front porch, the sync period and the back
> > > > > > > porch.
> > > > > > >
> > > > > > > In your case, you expand it to the displayed area, the front porch and
> > > > > > > the back porch, precisely because in Allwinner's case, the back porch
> > > > > > > has the sync period.
> > > > > >
> > > > > > I understand the point, but technically it matter about the final
> > > > > > computation result.  May be we can even manage the same computation in
> > > > > > back porch, but I'm not sure. Since the final output doesn't involve
> > > > > > any sync length, why we can include that ie what I'm not sure.
> > > > >
> > > > > We have the following formula:
> > > > > lcd_ht - lcd_x - lcd_hbp - 20
> > > > >
> > > > > Using the concepts as they are defined in DRM, this expands to:
> > > > > x + hbp + hsync + hfp - x - hbp - 20
> > > >
> > > > Here is diff between allwinner hbp vs hbp in DRM.
> > > >
> > > > Say hbp in DRM can call it hbackporch, so
> > > >
> > > > => x + hbackporch + hsync + hfp - -x - hbp - 20
> > > >
> > > > (and here we need to substitute hbp formula from allwinner since the
> > > > actual equation would coming from there
> > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046)
> > >
> > > And this is precisely what needs to be said, with an explanation about
> > > where that hor_back_porch is being used later on, and what impact it
> > > could have.
> >
> > Yes, it an equation and the mathematical equations can be substitute
> > to variety kind I did agree with that, whether you can use hbackporch
> > or not or use another-way the final resulting value is equivalent to
> > the value of front porch. In that case we can solve based on what I
> > explained above. If you still dought me, please run BSP and check the
> > resulting value on this check, you can get the front porch value.
>
> Maxime is not doubting you. He is saying that you need to include the
> detailed explanation in your commit log, and not just reference pieces
> of code. This is separate from the requirement of having a correct patch.
>
> Providing just a mathematical formula isn't enough either, because it
> is not clear to the average reader which term expanded into what. A

Not sure whether you see my commit log on this version or not. Each
one has it's own way of providing the details and explanation and at
the end people in ML should understand it. I'm not proving a simple
formula here (like I did it in initial version) instead I'm giving all
the respective information along with the bug log, and the bsp links
where it comes from etc. This is easier way for everyone to
understand.

Just a bit to explain what I've mentioned in the log.

Paragraph 1:

"
According to "DRM kernel-internal display mode structure" in
include/drm/drm_modes.h the current driver is trying to include
sync timings along with front porch value while checking and
computing drq set bits in non-burst mode.

mode->hsync_end - mode->hdisplay => horizontal front porch + sync
"

This paragraph explains what the existing code is using according to
DRM, which indeed help new users to understand by providing
include/drm/drm_modes.h file.

Paragraph 2:

"
With adding additional sync timings, the dsi controller leads to
wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
trigger panel flip_done timed out as:
"

This paragraph explains what is the relevant issue with existing change.

Paragraph 3:

BUG or WARNING log

Paragraph 4:

"
But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
non-burst DSI mode can be computed based on "horizontal front porch"
value only (no sync timings included).
"

This paragraph explains what is BSP is using compared with mainline.

Paragraph 5:

"
Detailed evidence for drq set bits based on A33 BSP [1] [2]

=> panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
=> (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
=> tt->hor_front_porch - 20
"

This paragraph explains the detailed steps of equation evaluation by
providing BSP links.

Paragraph 6:

"
Which is mode->hsync_start - mode->hdisplay as per
"DRM kernel-internal display mode structure" in include/drm/drm_modes.h
"

This paragraph give fix details in according to Linux DRM.

So, all the explanation which I'm trying to provide here will help to
understand, what is the issue with existing code and BUG log, how it
handle in BSP, with justification of equations and links where it
refers. Please note that I'm providing bug log and before that I've
mentioned this timeout because of additional sync. why is the timeout
with additional sync time, which I'm unaware since we don't have
associated datasheets for this but we have working BSP's to prove
that.

Frankly, I still didn't understand what I missed here to explain the
issue. request for help if you see any issues on this format or
information.

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-06-18 12:11                         ` Jagan Teki
@ 2019-06-18 14:45                           ` Chen-Yu Tsai
  2019-06-20 18:51                             ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Chen-Yu Tsai @ 2019-06-18 14:45 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, 坚定前行,
	Maxime Ripard, linux-kernel, dri-devel, David Airlie,
	linux-sunxi, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Tue, Jun 18, 2019 at 8:11 PM Jagan Teki <jagan@amarulasolutions.com> wrote:
>
> On Tue, Jun 18, 2019 at 5:13 PM Chen-Yu Tsai <wens@csie.org> wrote:
> >
> > On Tue, Jun 18, 2019 at 6:51 PM Jagan Teki <jagan@amarulasolutions.com> wrote:
> > >
> > > On Fri, Jun 14, 2019 at 8:15 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > >
> > > > On Fri, Jun 14, 2019 at 12:03:13PM +0530, Jagan Teki wrote:
> > > > > On Thu, Jun 13, 2019 at 6:56 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > >
> > > > > > On Wed, Jun 05, 2019 at 01:17:11PM +0530, Jagan Teki wrote:
> > > > > > > On Tue, Jun 4, 2019 at 3:30 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > >
> > > > > > > > On Wed, May 29, 2019 at 11:44:56PM +0530, Jagan Teki wrote:
> > > > > > > > > On Wed, May 29, 2019 at 8:24 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > > >
> > > > > > > > > > On Fri, May 24, 2019 at 03:48:51PM +0530, Jagan Teki wrote:
> > > > > > > > > > > On Fri, May 24, 2019 at 2:04 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > > > > >
> > > > > > > > > > > > On Mon, May 20, 2019 at 02:33:08PM +0530, Jagan Teki wrote:
> > > > > > > > > > > > > According to "DRM kernel-internal display mode structure" in
> > > > > > > > > > > > > include/drm/drm_modes.h the current driver is trying to include
> > > > > > > > > > > > > sync timings along with front porch value while checking and
> > > > > > > > > > > > > computing drq set bits in non-burst mode.
> > > > > > > > > > > > >
> > > > > > > > > > > > > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> > > > > > > > > > > > >
> > > > > > > > > > > > > With adding additional sync timings, the dsi controller leads to
> > > > > > > > > > > > > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > > > > > > > > > > > > trigger panel flip_done timed out as:
> > > > > > > > > > > > >
> > > > > > > > > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > > > > > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > > > > > > > > >  Modules linked in:
> > > > > > > > > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
> > > > > > > > > > > > >  Hardware name: Allwinner sun8i Family
> > > > > > > > > > > > >  Workqueue: events deferred_probe_work_func
> > > > > > > > > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > > > > > > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > > > > > > > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > > > > > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > > > > > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > > > > > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > > > > > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > > > > > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > > > > > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > > > > > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > > > > > > > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > > > > > > > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > > > > > > > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > > > > > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > > > > > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > > > > > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > > > > > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > > > > > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > > > > > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > > > > > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > > > > > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > > > > > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > > > > > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > > > > > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > > > > > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > > > > > > > > >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> > > > > > > > > > > > >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > > > > > > > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> > > > > > > > > > > > >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> > > > > > > > > > > > >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> > > > > > > > > > > > >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> > > > > > > > > > > > >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> > > > > > > > > > > > >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> > > > > > > > > > > > >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> > > > > > > > > > > > >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > > > > > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > > > > > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > > > > > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > > > > > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > > > > > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > > > > > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > > > > > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > > > > > > > > >  ---[ end trace b57eb1e5c64c6b8b ]---
> > > > > > > > > > > > >  random: fast init done
> > > > > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > > > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > > > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > > > > > > > > > > >
> > > > > > > > > > > > > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > > > > > > > > > > > > non-burst DSI mode can be computed based on "horizontal front porch"
> > > > > > > > > > > > > value only (no sync timings included).
> > > > > > > > > > > > >
> > > > > > > > > > > > > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> > > > > > > > > > > > >
> > > > > > > > > > > > > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > > > > > > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > > > > > > > > > > > > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > > > > > > => tt->hor_front_porch - 20
> > > > > > > > > > > >
> > > > > > > > > > > > The thing is, while your explanation on the DRM side is sound,
> > > > > > > > > > > > Allwinner has been using the hbp field of their panel description to
> > > > > > > > > > > > store what DRM calls the backporch and the sync period.
> > > > > > > > > > >
> > > > > > > > > > > Exactly, hbp = backporch + sync
> > > > > > > > > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046
> > > > > > > > > > >
> > > > > > > > > > > And the above computation is rely on that as well. If you can see the
> > > > > > > > > > > final out of the above computation you can get the front porch value
> > > > > > > > > > > (w/o sync )
> > > > > > > > > >
> > > > > > > > > > As I was saying, you are explaining it well for DRM, but in order for
> > > > > > > > > > your last formula (the one coming from the BSP) to make sense, you
> > > > > > > > > > have to explain that the horizontal back porch for Allwinner contains
> > > > > > > > > > the sync period, otherwise your expansion of lcd_ht doesn't make
> > > > > > > > > > sense.
> > > > > > > > >
> > > > > > > > > I'm not sure why we need to take care of back porch since the formula
> > > > > > > > > clearly evaluating a result as front porch, without sync timing (as
> > > > > > > > > current code included this sync), I keep the hbp and trying to
> > > > > > > > > substitute the lcd_ht value so the end result would cancel hbp.
> > > > > > > >
> > > > > > > > Because it changes how lcd_ht expands. In the DRM case, it will expand
> > > > > > > > to the displayed area, the front porch, the sync period and the back
> > > > > > > > porch.
> > > > > > > >
> > > > > > > > In your case, you expand it to the displayed area, the front porch and
> > > > > > > > the back porch, precisely because in Allwinner's case, the back porch
> > > > > > > > has the sync period.
> > > > > > >
> > > > > > > I understand the point, but technically it matter about the final
> > > > > > > computation result.  May be we can even manage the same computation in
> > > > > > > back porch, but I'm not sure. Since the final output doesn't involve
> > > > > > > any sync length, why we can include that ie what I'm not sure.
> > > > > >
> > > > > > We have the following formula:
> > > > > > lcd_ht - lcd_x - lcd_hbp - 20
> > > > > >
> > > > > > Using the concepts as they are defined in DRM, this expands to:
> > > > > > x + hbp + hsync + hfp - x - hbp - 20
> > > > >
> > > > > Here is diff between allwinner hbp vs hbp in DRM.
> > > > >
> > > > > Say hbp in DRM can call it hbackporch, so
> > > > >
> > > > > => x + hbackporch + hsync + hfp - -x - hbp - 20
> > > > >
> > > > > (and here we need to substitute hbp formula from allwinner since the
> > > > > actual equation would coming from there
> > > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046)
> > > >
> > > > And this is precisely what needs to be said, with an explanation about
> > > > where that hor_back_porch is being used later on, and what impact it
> > > > could have.
> > >
> > > Yes, it an equation and the mathematical equations can be substitute
> > > to variety kind I did agree with that, whether you can use hbackporch
> > > or not or use another-way the final resulting value is equivalent to
> > > the value of front porch. In that case we can solve based on what I
> > > explained above. If you still dought me, please run BSP and check the
> > > resulting value on this check, you can get the front porch value.
> >
> > Maxime is not doubting you. He is saying that you need to include the
> > detailed explanation in your commit log, and not just reference pieces
> > of code. This is separate from the requirement of having a correct patch.
> >
> > Providing just a mathematical formula isn't enough either, because it
> > is not clear to the average reader which term expanded into what. A
>
> Not sure whether you see my commit log on this version or not. Each
> one has it's own way of providing the details and explanation and at
> the end people in ML should understand it. I'm not proving a simple
> formula here (like I did it in initial version) instead I'm giving all
> the respective information along with the bug log, and the bsp links
> where it comes from etc. This is easier way for everyone to
> understand.

I did, and I'm telling you it's not easy to follow.

> Just a bit to explain what I've mentioned in the log.
>
> Paragraph 1:
>
> "
> According to "DRM kernel-internal display mode structure" in
> include/drm/drm_modes.h the current driver is trying to include
> sync timings along with front porch value while checking and
> computing drq set bits in non-burst mode.
>
> mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> "
>
> This paragraph explains what the existing code is using according to
> DRM, which indeed help new users to understand by providing
> include/drm/drm_modes.h file.

This at the beginning makes no sense. It would be better placed with
the formula after
the bug report

> Paragraph 2:
>
> "
> With adding additional sync timings, the dsi controller leads to
> wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> trigger panel flip_done timed out as:
> "
>
> This paragraph explains what is the relevant issue with existing change.
>
> Paragraph 3:
>
> BUG or WARNING log

You should lead with these two. These explain "why".

> Paragraph 4:
>
> "
> But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> non-burst DSI mode can be computed based on "horizontal front porch"
> value only (no sync timings included).
> "
>
> This paragraph explains what is BSP is using compared with mainline.
>
> Paragraph 5:
>
> "
> Detailed evidence for drq set bits based on A33 BSP [1] [2]
>
> => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> => tt->hor_front_porch - 20
> "
>
> This paragraph explains the detailed steps of equation evaluation by
> providing BSP links.

This actually makes it harder to read. For example it takes a couple passes
to realize lcd_ht expands to the stuff in the parenthesis. All the while I
still have no idea what all these variables mean or where they came from.
As I said, please don't ask users to open links and dig through code.

You should provide a simple explanation about what went wrong. As I
mentioned, you could have simply stated that when the driver was
reimplemented, the DRQ formula (which you can provide in its original
form) was incorrectly expanded because Allwinner's definition of "hbp"
is actually "hbp + sync" in DRM terms. That is actually the root cause,
which I believe is what Maxime wants detailed in the commit log.
This immediately points out what went wrong and how it went wrong,
without jumping through hoops.

Again the diagram helps immensely. (Well, maybe not for screen readers.)
It also directly shows why you replaced hsync_end with hsync_start.

> Paragraph 6:
>
> "
> Which is mode->hsync_start - mode->hdisplay as per
> "DRM kernel-internal display mode structure" in include/drm/drm_modes.h
> "
>
> This paragraph give fix details in according to Linux DRM.

Yes, and first you need to understand the formula you gave, which I
already mentioned is a bit hard.

On the side, going through the code and understanding it actually is quite
hard as I already did it a couple times before and it was really taxing.

> So, all the explanation which I'm trying to provide here will help to
> understand, what is the issue with existing code and BUG log, how it
> handle in BSP, with justification of equations and links where it
> refers. Please note that I'm providing bug log and before that I've
> mentioned this timeout because of additional sync. why is the timeout
> with additional sync time, which I'm unaware since we don't have
> associated datasheets for this but we have working BSP's to prove
> that.
>
> Frankly, I still didn't understand what I missed here to explain the
> issue. request for help if you see any issues on this format or
> information.

The one thing you missed, and that Maxime requested, was how hbp, and
the misinterpretation of it plays into all of this. In fact the different
definitions of terms between DRM and Allwinner code / FEX files is what
led to all this. The rest is, well, somewhat hard to read. I already
shared my way of explaining everything above.

ChenYu

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-06-18 14:45                           ` Chen-Yu Tsai
@ 2019-06-20 18:51                             ` Jagan Teki
  2019-06-21  3:13                               ` Chen-Yu Tsai
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-06-20 18:51 UTC (permalink / raw)
  To: Chen-Yu Tsai
  Cc: Bhushan Shah, 坚定前行,
	Maxime Ripard, linux-kernel, dri-devel, David Airlie,
	linux-sunxi, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Tue, Jun 18, 2019 at 8:15 PM Chen-Yu Tsai <wens@csie.org> wrote:
>
> On Tue, Jun 18, 2019 at 8:11 PM Jagan Teki <jagan@amarulasolutions.com> wrote:
> >
> > On Tue, Jun 18, 2019 at 5:13 PM Chen-Yu Tsai <wens@csie.org> wrote:
> > >
> > > On Tue, Jun 18, 2019 at 6:51 PM Jagan Teki <jagan@amarulasolutions.com> wrote:
> > > >
> > > > On Fri, Jun 14, 2019 at 8:15 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > >
> > > > > On Fri, Jun 14, 2019 at 12:03:13PM +0530, Jagan Teki wrote:
> > > > > > On Thu, Jun 13, 2019 at 6:56 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > >
> > > > > > > On Wed, Jun 05, 2019 at 01:17:11PM +0530, Jagan Teki wrote:
> > > > > > > > On Tue, Jun 4, 2019 at 3:30 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > >
> > > > > > > > > On Wed, May 29, 2019 at 11:44:56PM +0530, Jagan Teki wrote:
> > > > > > > > > > On Wed, May 29, 2019 at 8:24 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > > > >
> > > > > > > > > > > On Fri, May 24, 2019 at 03:48:51PM +0530, Jagan Teki wrote:
> > > > > > > > > > > > On Fri, May 24, 2019 at 2:04 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > > > > > >
> > > > > > > > > > > > > On Mon, May 20, 2019 at 02:33:08PM +0530, Jagan Teki wrote:
> > > > > > > > > > > > > > According to "DRM kernel-internal display mode structure" in
> > > > > > > > > > > > > > include/drm/drm_modes.h the current driver is trying to include
> > > > > > > > > > > > > > sync timings along with front porch value while checking and
> > > > > > > > > > > > > > computing drq set bits in non-burst mode.
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > With adding additional sync timings, the dsi controller leads to
> > > > > > > > > > > > > > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > > > > > > > > > > > > > trigger panel flip_done timed out as:
> > > > > > > > > > > > > >
> > > > > > > > > > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > > > > > > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > > > > > > > > > >  Modules linked in:
> > > > > > > > > > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
> > > > > > > > > > > > > >  Hardware name: Allwinner sun8i Family
> > > > > > > > > > > > > >  Workqueue: events deferred_probe_work_func
> > > > > > > > > > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > > > > > > > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > > > > > > > > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > > > > > > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > > > > > > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > > > > > > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > > > > > > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > > > > > > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > > > > > > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > > > > > > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > > > > > > > > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > > > > > > > > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > > > > > > > > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > > > > > > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > > > > > > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > > > > > > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > > > > > > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > > > > > > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > > > > > > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > > > > > > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > > > > > > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > > > > > > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > > > > > > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > > > > > > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > > > > > > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > > > > > > > > > >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> > > > > > > > > > > > > >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > > > > > > > > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> > > > > > > > > > > > > >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> > > > > > > > > > > > > >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> > > > > > > > > > > > > >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> > > > > > > > > > > > > >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> > > > > > > > > > > > > >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> > > > > > > > > > > > > >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> > > > > > > > > > > > > >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > > > > > > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > > > > > > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > > > > > > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > > > > > > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > > > > > > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > > > > > > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > > > > > > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > > > > > > > > > >  ---[ end trace b57eb1e5c64c6b8b ]---
> > > > > > > > > > > > > >  random: fast init done
> > > > > > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > > > > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > > > > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > > > > > > > > > > > > > non-burst DSI mode can be computed based on "horizontal front porch"
> > > > > > > > > > > > > > value only (no sync timings included).
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > > > > > > > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > > > > > > > > > > > > > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > > > > > > > => tt->hor_front_porch - 20
> > > > > > > > > > > > >
> > > > > > > > > > > > > The thing is, while your explanation on the DRM side is sound,
> > > > > > > > > > > > > Allwinner has been using the hbp field of their panel description to
> > > > > > > > > > > > > store what DRM calls the backporch and the sync period.
> > > > > > > > > > > >
> > > > > > > > > > > > Exactly, hbp = backporch + sync
> > > > > > > > > > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046
> > > > > > > > > > > >
> > > > > > > > > > > > And the above computation is rely on that as well. If you can see the
> > > > > > > > > > > > final out of the above computation you can get the front porch value
> > > > > > > > > > > > (w/o sync )
> > > > > > > > > > >
> > > > > > > > > > > As I was saying, you are explaining it well for DRM, but in order for
> > > > > > > > > > > your last formula (the one coming from the BSP) to make sense, you
> > > > > > > > > > > have to explain that the horizontal back porch for Allwinner contains
> > > > > > > > > > > the sync period, otherwise your expansion of lcd_ht doesn't make
> > > > > > > > > > > sense.
> > > > > > > > > >
> > > > > > > > > > I'm not sure why we need to take care of back porch since the formula
> > > > > > > > > > clearly evaluating a result as front porch, without sync timing (as
> > > > > > > > > > current code included this sync), I keep the hbp and trying to
> > > > > > > > > > substitute the lcd_ht value so the end result would cancel hbp.
> > > > > > > > >
> > > > > > > > > Because it changes how lcd_ht expands. In the DRM case, it will expand
> > > > > > > > > to the displayed area, the front porch, the sync period and the back
> > > > > > > > > porch.
> > > > > > > > >
> > > > > > > > > In your case, you expand it to the displayed area, the front porch and
> > > > > > > > > the back porch, precisely because in Allwinner's case, the back porch
> > > > > > > > > has the sync period.
> > > > > > > >
> > > > > > > > I understand the point, but technically it matter about the final
> > > > > > > > computation result.  May be we can even manage the same computation in
> > > > > > > > back porch, but I'm not sure. Since the final output doesn't involve
> > > > > > > > any sync length, why we can include that ie what I'm not sure.
> > > > > > >
> > > > > > > We have the following formula:
> > > > > > > lcd_ht - lcd_x - lcd_hbp - 20
> > > > > > >
> > > > > > > Using the concepts as they are defined in DRM, this expands to:
> > > > > > > x + hbp + hsync + hfp - x - hbp - 20
> > > > > >
> > > > > > Here is diff between allwinner hbp vs hbp in DRM.
> > > > > >
> > > > > > Say hbp in DRM can call it hbackporch, so
> > > > > >
> > > > > > => x + hbackporch + hsync + hfp - -x - hbp - 20
> > > > > >
> > > > > > (and here we need to substitute hbp formula from allwinner since the
> > > > > > actual equation would coming from there
> > > > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046)
> > > > >
> > > > > And this is precisely what needs to be said, with an explanation about
> > > > > where that hor_back_porch is being used later on, and what impact it
> > > > > could have.
> > > >
> > > > Yes, it an equation and the mathematical equations can be substitute
> > > > to variety kind I did agree with that, whether you can use hbackporch
> > > > or not or use another-way the final resulting value is equivalent to
> > > > the value of front porch. In that case we can solve based on what I
> > > > explained above. If you still dought me, please run BSP and check the
> > > > resulting value on this check, you can get the front porch value.
> > >
> > > Maxime is not doubting you. He is saying that you need to include the
> > > detailed explanation in your commit log, and not just reference pieces
> > > of code. This is separate from the requirement of having a correct patch.
> > >
> > > Providing just a mathematical formula isn't enough either, because it
> > > is not clear to the average reader which term expanded into what. A
> >
> > Not sure whether you see my commit log on this version or not. Each
> > one has it's own way of providing the details and explanation and at
> > the end people in ML should understand it. I'm not proving a simple
> > formula here (like I did it in initial version) instead I'm giving all
> > the respective information along with the bug log, and the bsp links
> > where it comes from etc. This is easier way for everyone to
> > understand.
>
> I did, and I'm telling you it's not easy to follow.
>
> > Just a bit to explain what I've mentioned in the log.
> >
> > Paragraph 1:
> >
> > "
> > According to "DRM kernel-internal display mode structure" in
> > include/drm/drm_modes.h the current driver is trying to include
> > sync timings along with front porch value while checking and
> > computing drq set bits in non-burst mode.
> >
> > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> > "
> >
> > This paragraph explains what the existing code is using according to
> > DRM, which indeed help new users to understand by providing
> > include/drm/drm_modes.h file.
>
> This at the beginning makes no sense. It would be better placed with
> the formula after
> the bug report
>
> > Paragraph 2:
> >
> > "
> > With adding additional sync timings, the dsi controller leads to
> > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > trigger panel flip_done timed out as:
> > "
> >
> > This paragraph explains what is the relevant issue with existing change.
> >
> > Paragraph 3:
> >
> > BUG or WARNING log
>
> You should lead with these two. These explain "why".
>
> > Paragraph 4:
> >
> > "
> > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > non-burst DSI mode can be computed based on "horizontal front porch"
> > value only (no sync timings included).
> > "
> >
> > This paragraph explains what is BSP is using compared with mainline.
> >
> > Paragraph 5:
> >
> > "
> > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> >
> > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > => tt->hor_front_porch - 20
> > "
> >
> > This paragraph explains the detailed steps of equation evaluation by
> > providing BSP links.
>
> This actually makes it harder to read. For example it takes a couple passes
> to realize lcd_ht expands to the stuff in the parenthesis. All the while I
> still have no idea what all these variables mean or where they came from.
> As I said, please don't ask users to open links and dig through code.

The main reasons I have included this information and the BSP links
are for future reference, to know the real proofs if anyone would want
to. and even the timeout log. My idea of formula evaluation here just
like what you refer in the diagram in previous mail. I thought
mathematical equations are much easier to understand and provable.

>
> You should provide a simple explanation about what went wrong. As I
> mentioned, you could have simply stated that when the driver was
> reimplemented, the DRQ formula (which you can provide in its original
> form) was incorrectly expanded because Allwinner's definition of "hbp"
> is actually "hbp + sync" in DRM terms. That is actually the root cause,
> which I believe is what Maxime wants detailed in the commit log.
> This immediately points out what went wrong and how it went wrong,
> without jumping through hoops.
>
> Again the diagram helps immensely. (Well, maybe not for screen readers.)
> It also directly shows why you replaced hsync_end with hsync_start.

True, this indeed has different and direct understanding of what went
wrong. thanks for this.

>
> > Paragraph 6:
> >
> > "
> > Which is mode->hsync_start - mode->hdisplay as per
> > "DRM kernel-internal display mode structure" in include/drm/drm_modes.h
> > "
> >
> > This paragraph give fix details in according to Linux DRM.
>
> Yes, and first you need to understand the formula you gave, which I
> already mentioned is a bit hard.
>
> On the side, going through the code and understanding it actually is quite
> hard as I already did it a couple times before and it was really taxing.
>
> > So, all the explanation which I'm trying to provide here will help to
> > understand, what is the issue with existing code and BUG log, how it
> > handle in BSP, with justification of equations and links where it
> > refers. Please note that I'm providing bug log and before that I've
> > mentioned this timeout because of additional sync. why is the timeout
> > with additional sync time, which I'm unaware since we don't have
> > associated datasheets for this but we have working BSP's to prove
> > that.
> >
> > Frankly, I still didn't understand what I missed here to explain the
> > issue. request for help if you see any issues on this format or
> > information.
>
> The one thing you missed, and that Maxime requested, was how hbp, and
> the misinterpretation of it plays into all of this. In fact the different
> definitions of terms between DRM and Allwinner code / FEX files is what
> led to all this. The rest is, well, somewhat hard to read. I already
> shared my way of explaining everything above.

Okay, will try to re-arrange the commit in next version. hope this
time will more cleaner. thanks.

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits
  2019-06-20 18:51                             ` Jagan Teki
@ 2019-06-21  3:13                               ` Chen-Yu Tsai
  0 siblings, 0 replies; 54+ messages in thread
From: Chen-Yu Tsai @ 2019-06-21  3:13 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, 坚定前行,
	Michael Trimarchi, Maxime Ripard, linux-kernel, dri-devel,
	David Airlie, linux-sunxi, Daniel Vetter, Chen-Yu Tsai,
	linux-amarula, linux-arm-kernel

On Fri, Jun 21, 2019 at 2:51 AM Jagan Teki <jagan@amarulasolutions.com> wrote:
>
> On Tue, Jun 18, 2019 at 8:15 PM Chen-Yu Tsai <wens@csie.org> wrote:
> >
> > On Tue, Jun 18, 2019 at 8:11 PM Jagan Teki <jagan@amarulasolutions.com> wrote:
> > >
> > > On Tue, Jun 18, 2019 at 5:13 PM Chen-Yu Tsai <wens@csie.org> wrote:
> > > >
> > > > On Tue, Jun 18, 2019 at 6:51 PM Jagan Teki <jagan@amarulasolutions.com> wrote:
> > > > >
> > > > > On Fri, Jun 14, 2019 at 8:15 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > >
> > > > > > On Fri, Jun 14, 2019 at 12:03:13PM +0530, Jagan Teki wrote:
> > > > > > > On Thu, Jun 13, 2019 at 6:56 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > >
> > > > > > > > On Wed, Jun 05, 2019 at 01:17:11PM +0530, Jagan Teki wrote:
> > > > > > > > > On Tue, Jun 4, 2019 at 3:30 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > > >
> > > > > > > > > > On Wed, May 29, 2019 at 11:44:56PM +0530, Jagan Teki wrote:
> > > > > > > > > > > On Wed, May 29, 2019 at 8:24 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > > > > >
> > > > > > > > > > > > On Fri, May 24, 2019 at 03:48:51PM +0530, Jagan Teki wrote:
> > > > > > > > > > > > > On Fri, May 24, 2019 at 2:04 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > On Mon, May 20, 2019 at 02:33:08PM +0530, Jagan Teki wrote:
> > > > > > > > > > > > > > > According to "DRM kernel-internal display mode structure" in
> > > > > > > > > > > > > > > include/drm/drm_modes.h the current driver is trying to include
> > > > > > > > > > > > > > > sync timings along with front porch value while checking and
> > > > > > > > > > > > > > > computing drq set bits in non-burst mode.
> > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > With adding additional sync timings, the dsi controller leads to
> > > > > > > > > > > > > > > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > > > > > > > > > > > > > > trigger panel flip_done timed out as:
> > > > > > > > > > > > > > >
> > > > > > > > > > > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > > > > > > > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > > > > > > > > > > >  Modules linked in:
> > > > > > > > > > > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00026-g01f0c75b902d-dirty #13
> > > > > > > > > > > > > > >  Hardware name: Allwinner sun8i Family
> > > > > > > > > > > > > > >  Workqueue: events deferred_probe_work_func
> > > > > > > > > > > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > > > > > > > > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > > > > > > > > > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > > > > > > > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > > > > > > > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > > > > > > > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > > > > > > > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > > > > > > > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > > > > > > > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > > > > > > > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > > > > > > > > > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > > > > > > > > > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > > > > > > > > > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > > > > > > > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > > > > > > > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > > > > > > > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > > > > > > > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > > > > > > > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > > > > > > > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > > > > > > > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > > > > > > > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > > > > > > > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > > > > > > > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > > > > > > > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > > > > > > > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > > > > > > > > > > >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> > > > > > > > > > > > > > >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > > > > > > > > > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> > > > > > > > > > > > > > >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> > > > > > > > > > > > > > >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> > > > > > > > > > > > > > >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> > > > > > > > > > > > > > >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> > > > > > > > > > > > > > >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> > > > > > > > > > > > > > >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> > > > > > > > > > > > > > >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > > > > > > > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > > > > > > > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > > > > > > > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > > > > > > > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > > > > > > > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > > > > > > > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > > > > > > > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > > > > > > > > > > >  ---[ end trace b57eb1e5c64c6b8b ]---
> > > > > > > > > > > > > > >  random: fast init done
> > > > > > > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > > > > > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > > > > > > > > > > > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > > > > > > > > > > > > > > non-burst DSI mode can be computed based on "horizontal front porch"
> > > > > > > > > > > > > > > value only (no sync timings included).
> > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> > > > > > > > > > > > > > >
> > > > > > > > > > > > > > > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > > > > > > > > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > > > > > > > > > > > > > > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > > > > > > > > > > > > > > => tt->hor_front_porch - 20
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > The thing is, while your explanation on the DRM side is sound,
> > > > > > > > > > > > > > Allwinner has been using the hbp field of their panel description to
> > > > > > > > > > > > > > store what DRM calls the backporch and the sync period.
> > > > > > > > > > > > >
> > > > > > > > > > > > > Exactly, hbp = backporch + sync
> > > > > > > > > > > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046
> > > > > > > > > > > > >
> > > > > > > > > > > > > And the above computation is rely on that as well. If you can see the
> > > > > > > > > > > > > final out of the above computation you can get the front porch value
> > > > > > > > > > > > > (w/o sync )
> > > > > > > > > > > >
> > > > > > > > > > > > As I was saying, you are explaining it well for DRM, but in order for
> > > > > > > > > > > > your last formula (the one coming from the BSP) to make sense, you
> > > > > > > > > > > > have to explain that the horizontal back porch for Allwinner contains
> > > > > > > > > > > > the sync period, otherwise your expansion of lcd_ht doesn't make
> > > > > > > > > > > > sense.
> > > > > > > > > > >
> > > > > > > > > > > I'm not sure why we need to take care of back porch since the formula
> > > > > > > > > > > clearly evaluating a result as front porch, without sync timing (as
> > > > > > > > > > > current code included this sync), I keep the hbp and trying to
> > > > > > > > > > > substitute the lcd_ht value so the end result would cancel hbp.
> > > > > > > > > >
> > > > > > > > > > Because it changes how lcd_ht expands. In the DRM case, it will expand
> > > > > > > > > > to the displayed area, the front porch, the sync period and the back
> > > > > > > > > > porch.
> > > > > > > > > >
> > > > > > > > > > In your case, you expand it to the displayed area, the front porch and
> > > > > > > > > > the back porch, precisely because in Allwinner's case, the back porch
> > > > > > > > > > has the sync period.
> > > > > > > > >
> > > > > > > > > I understand the point, but technically it matter about the final
> > > > > > > > > computation result.  May be we can even manage the same computation in
> > > > > > > > > back porch, but I'm not sure. Since the final output doesn't involve
> > > > > > > > > any sync length, why we can include that ie what I'm not sure.
> > > > > > > >
> > > > > > > > We have the following formula:
> > > > > > > > lcd_ht - lcd_x - lcd_hbp - 20
> > > > > > > >
> > > > > > > > Using the concepts as they are defined in DRM, this expands to:
> > > > > > > > x + hbp + hsync + hfp - x - hbp - 20
> > > > > > >
> > > > > > > Here is diff between allwinner hbp vs hbp in DRM.
> > > > > > >
> > > > > > > Say hbp in DRM can call it hbackporch, so
> > > > > > >
> > > > > > > => x + hbackporch + hsync + hfp - -x - hbp - 20
> > > > > > >
> > > > > > > (and here we need to substitute hbp formula from allwinner since the
> > > > > > > actual equation would coming from there
> > > > > > > https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L2046)
> > > > > >
> > > > > > And this is precisely what needs to be said, with an explanation about
> > > > > > where that hor_back_porch is being used later on, and what impact it
> > > > > > could have.
> > > > >
> > > > > Yes, it an equation and the mathematical equations can be substitute
> > > > > to variety kind I did agree with that, whether you can use hbackporch
> > > > > or not or use another-way the final resulting value is equivalent to
> > > > > the value of front porch. In that case we can solve based on what I
> > > > > explained above. If you still dought me, please run BSP and check the
> > > > > resulting value on this check, you can get the front porch value.
> > > >
> > > > Maxime is not doubting you. He is saying that you need to include the
> > > > detailed explanation in your commit log, and not just reference pieces
> > > > of code. This is separate from the requirement of having a correct patch.
> > > >
> > > > Providing just a mathematical formula isn't enough either, because it
> > > > is not clear to the average reader which term expanded into what. A
> > >
> > > Not sure whether you see my commit log on this version or not. Each
> > > one has it's own way of providing the details and explanation and at
> > > the end people in ML should understand it. I'm not proving a simple
> > > formula here (like I did it in initial version) instead I'm giving all
> > > the respective information along with the bug log, and the bsp links
> > > where it comes from etc. This is easier way for everyone to
> > > understand.
> >
> > I did, and I'm telling you it's not easy to follow.
> >
> > > Just a bit to explain what I've mentioned in the log.
> > >
> > > Paragraph 1:
> > >
> > > "
> > > According to "DRM kernel-internal display mode structure" in
> > > include/drm/drm_modes.h the current driver is trying to include
> > > sync timings along with front porch value while checking and
> > > computing drq set bits in non-burst mode.
> > >
> > > mode->hsync_end - mode->hdisplay => horizontal front porch + sync
> > > "
> > >
> > > This paragraph explains what the existing code is using according to
> > > DRM, which indeed help new users to understand by providing
> > > include/drm/drm_modes.h file.
> >
> > This at the beginning makes no sense. It would be better placed with
> > the formula after
> > the bug report
> >
> > > Paragraph 2:
> > >
> > > "
> > > With adding additional sync timings, the dsi controller leads to
> > > wrong drq set bits for "bananapi,s070wv20-ct16" panel which indeed
> > > trigger panel flip_done timed out as:
> > > "
> > >
> > > This paragraph explains what is the relevant issue with existing change.
> > >
> > > Paragraph 3:
> > >
> > > BUG or WARNING log
> >
> > You should lead with these two. These explain "why".
> >
> > > Paragraph 4:
> > >
> > > "
> > > But according to Allwinner A33, A64 BSP code [1] [3] the TCON DRQ for
> > > non-burst DSI mode can be computed based on "horizontal front porch"
> > > value only (no sync timings included).
> > > "
> > >
> > > This paragraph explains what is BSP is using compared with mainline.
> > >
> > > Paragraph 5:
> > >
> > > "
> > > Detailed evidence for drq set bits based on A33 BSP [1] [2]
> > >
> > > => panel->lcd_ht - panel->lcd_x - panel->lcd_hbp - 20
> > > => (tt->hor_front_porch + lcdp->panel_info.lcd_hbp +
> > > lcdp->panel_info.lcd_x) - panel->lcd_x - panel->lcd_hbp - 20
> > > => tt->hor_front_porch - 20
> > > "
> > >
> > > This paragraph explains the detailed steps of equation evaluation by
> > > providing BSP links.
> >
> > This actually makes it harder to read. For example it takes a couple passes
> > to realize lcd_ht expands to the stuff in the parenthesis. All the while I
> > still have no idea what all these variables mean or where they came from.
> > As I said, please don't ask users to open links and dig through code.
>
> The main reasons I have included this information and the BSP links
> are for future reference, to know the real proofs if anyone would want
> to. and even the timeout log. My idea of formula evaluation here just
> like what you refer in the diagram in previous mail. I thought
> mathematical equations are much easier to understand and provable.

Unfortunately the plain-text formatting sometimes doesn't help. Simple
text descriptions work better in most cases, diffs in others. You can
still include the formula as a reference, but it is better to explain
it outright in simple sentences, rather than providing the formula and
guiding the reader through it.

ChenYu

> > You should provide a simple explanation about what went wrong. As I
> > mentioned, you could have simply stated that when the driver was
> > reimplemented, the DRQ formula (which you can provide in its original
> > form) was incorrectly expanded because Allwinner's definition of "hbp"
> > is actually "hbp + sync" in DRM terms. That is actually the root cause,
> > which I believe is what Maxime wants detailed in the commit log.
> > This immediately points out what went wrong and how it went wrong,
> > without jumping through hoops.
> >
> > Again the diagram helps immensely. (Well, maybe not for screen readers.)
> > It also directly shows why you replaced hsync_end with hsync_start.
>
> True, this indeed has different and direct understanding of what went
> wrong. thanks for this.
>
> >
> > > Paragraph 6:
> > >
> > > "
> > > Which is mode->hsync_start - mode->hdisplay as per
> > > "DRM kernel-internal display mode structure" in include/drm/drm_modes.h
> > > "
> > >
> > > This paragraph give fix details in according to Linux DRM.
> >
> > Yes, and first you need to understand the formula you gave, which I
> > already mentioned is a bit hard.
> >
> > On the side, going through the code and understanding it actually is quite
> > hard as I already did it a couple times before and it was really taxing.
> >
> > > So, all the explanation which I'm trying to provide here will help to
> > > understand, what is the issue with existing code and BUG log, how it
> > > handle in BSP, with justification of equations and links where it
> > > refers. Please note that I'm providing bug log and before that I've
> > > mentioned this timeout because of additional sync. why is the timeout
> > > with additional sync time, which I'm unaware since we don't have
> > > associated datasheets for this but we have working BSP's to prove
> > > that.
> > >
> > > Frankly, I still didn't understand what I missed here to explain the
> > > issue. request for help if you see any issues on this format or
> > > information.
> >
> > The one thing you missed, and that Maxime requested, was how hbp, and
> > the misinterpretation of it plays into all of this. In fact the different
> > definitions of terms between DRM and Allwinner code / FEX files is what
> > led to all this. The rest is, well, somewhat hard to read. I already
> > shared my way of explaining everything above.
>
> Okay, will try to re-arrange the commit in next version. hope this
> time will more cleaner. thanks.

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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 03/11] drm/sun4i: dsi: Fix video start delay computation
  2019-05-24 10:26     ` Jagan Teki
@ 2019-06-21  8:35       ` " Chen-Yu Tsai
  2019-06-24  8:52         ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Chen-Yu Tsai @ 2019-06-21  8:35 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, 坚定前行,
	Maxime Ripard, linux-kernel, dri-devel, David Airlie,
	linux-sunxi, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Fri, May 24, 2019 at 6:27 PM Jagan Teki <jagan@amarulasolutions.com> wrote:
>
> On Fri, May 24, 2019 at 2:18 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> >
> > On Mon, May 20, 2019 at 02:33:10PM +0530, Jagan Teki wrote:
> > > The current code is computing vertical video start delay as
> > >
> > > delay = mode->vtotal - (mode->vsync_end - mode->vdisplay) + start;
> > >
> > > On which the second parameter
> > >
> > > mode->vsync_end - mode->vdisplay = front porch + sync timings
> > >
> > > according to "DRM kernel-internal display mode structure" in
> > > include/drm/drm_modes.h
> > >
> > > With adding additional sync timings, the desired video start delay
> > > value as 510 for "bananapi,s070wv20-ct16" panel timings which indeed
> > > trigger panel flip_done timed out as:
> > >
> > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > >  [CRTC:46:crtc-0] vblank wait timed out
> > >  Modules linked in:
> > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00029-g09e5b0ed0a58 #18
> > >  Hardware name: Allwinner sun8i Family
> > >  Workqueue: events deferred_probe_work_func
> > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> > >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> > >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> > >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> > >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> > >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> > >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> > >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> > >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> > >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > >  9fa0:                                     00000000 00000000 00000000 00000000
> > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > >  ---[ end trace 495200a78b24980e ]---
> > >  random: fast init done
> > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > >
> > > But the expected video start delay value is 513 which states that
> > > the second parameter on the computation is "front porch" value
> > > (no sync timings included).
> > >
> > > This is clearly confirmed from the legacy [1] and new [2] bsp codes
> > > that the second parameter on the video start delay is "front porch"
> > >
> > > Here is the detailed evidence for calculating front porch as per
> > > bsp code.
> > >
> > > vfp = panel->lcd_vt - panel->lcd_y - panel->lcd_vbp
> > > => (panel->lcd_vt) - panel->lcd_y - panel->lcd_vbp
> > > => (tt->ver_front_porch + lcdp->panel_info.lcd_vbp
> > >     + lcdp->panel_info.lcd_y) -  panel->lcd_y - panel->lcd_vbp
> > > => tt->ver_front_porch
> >
> > The comment on patch 1 still applies on this patch
>
> Thanks, I have responded on that. Same applies here.

So this patch fixes the misinterpretation of Allwinner's back porch value,
much like patch 1, but this one is for the vertical back porch. So I think
you should follow the same advice I gave you for patch 1.

ChenYu

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 03/11] drm/sun4i: dsi: Fix video start delay computation
  2019-06-21  8:35       ` [linux-sunxi] " Chen-Yu Tsai
@ 2019-06-24  8:52         ` Jagan Teki
  0 siblings, 0 replies; 54+ messages in thread
From: Jagan Teki @ 2019-06-24  8:52 UTC (permalink / raw)
  To: Chen-Yu Tsai
  Cc: Bhushan Shah, 坚定前行,
	Maxime Ripard, linux-kernel, dri-devel, David Airlie,
	linux-sunxi, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Fri, Jun 21, 2019 at 2:05 PM Chen-Yu Tsai <wens@csie.org> wrote:
>
> On Fri, May 24, 2019 at 6:27 PM Jagan Teki <jagan@amarulasolutions.com> wrote:
> >
> > On Fri, May 24, 2019 at 2:18 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > >
> > > On Mon, May 20, 2019 at 02:33:10PM +0530, Jagan Teki wrote:
> > > > The current code is computing vertical video start delay as
> > > >
> > > > delay = mode->vtotal - (mode->vsync_end - mode->vdisplay) + start;
> > > >
> > > > On which the second parameter
> > > >
> > > > mode->vsync_end - mode->vdisplay = front porch + sync timings
> > > >
> > > > according to "DRM kernel-internal display mode structure" in
> > > > include/drm/drm_modes.h
> > > >
> > > > With adding additional sync timings, the desired video start delay
> > > > value as 510 for "bananapi,s070wv20-ct16" panel timings which indeed
> > > > trigger panel flip_done timed out as:
> > > >
> > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > >  Modules linked in:
> > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00029-g09e5b0ed0a58 #18
> > > >  Hardware name: Allwinner sun8i Family
> > > >  Workqueue: events deferred_probe_work_func
> > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b598>] (try_to_bring_up_master+0x164/0x1a0)
> > > >  [<c044b598>] (try_to_bring_up_master) from [<c044b668>] (__component_add+0x94/0x140)
> > > >  [<c044b668>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
> > > >  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452ef4>] (platform_drv_probe+0x48/0x9c)
> > > >  [<c0452ef4>] (platform_drv_probe) from [<c04512cc>] (really_probe+0x1dc/0x2c8)
> > > >  [<c04512cc>] (really_probe) from [<c0451518>] (driver_probe_device+0x60/0x160)
> > > >  [<c0451518>] (driver_probe_device) from [<c044f7a4>] (bus_for_each_drv+0x74/0xb8)
> > > >  [<c044f7a4>] (bus_for_each_drv) from [<c045107c>] (__device_attach+0xd0/0x13c)
> > > >  [<c045107c>] (__device_attach) from [<c0450474>] (bus_probe_device+0x84/0x8c)
> > > >  [<c0450474>] (bus_probe_device) from [<c0450900>] (deferred_probe_work_func+0x64/0x90)
> > > >  [<c0450900>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > >  ---[ end trace 495200a78b24980e ]---
> > > >  random: fast init done
> > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
> > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
> > > >  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
> > > >
> > > > But the expected video start delay value is 513 which states that
> > > > the second parameter on the computation is "front porch" value
> > > > (no sync timings included).
> > > >
> > > > This is clearly confirmed from the legacy [1] and new [2] bsp codes
> > > > that the second parameter on the video start delay is "front porch"
> > > >
> > > > Here is the detailed evidence for calculating front porch as per
> > > > bsp code.
> > > >
> > > > vfp = panel->lcd_vt - panel->lcd_y - panel->lcd_vbp
> > > > => (panel->lcd_vt) - panel->lcd_y - panel->lcd_vbp
> > > > => (tt->ver_front_porch + lcdp->panel_info.lcd_vbp
> > > >     + lcdp->panel_info.lcd_y) -  panel->lcd_y - panel->lcd_vbp
> > > > => tt->ver_front_porch
> > >
> > > The comment on patch 1 still applies on this patch
> >
> > Thanks, I have responded on that. Same applies here.
>
> So this patch fixes the misinterpretation of Allwinner's back porch value,
> much like patch 1, but this one is for the vertical back porch. So I think
> you should follow the same advice I gave you for patch 1.

Yes, indeed I'm planning to do the same. thanks!

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [PATCH v10 02/11] drm/sun4i: dsi: Update start value in video start delay
  2019-05-20  9:03 ` [PATCH v10 02/11] drm/sun4i: dsi: Update start value in video start delay Jagan Teki
  2019-05-23 20:37   ` Maxime Ripard
@ 2019-06-24  9:34   ` Chen-Yu Tsai
  1 sibling, 0 replies; 54+ messages in thread
From: Chen-Yu Tsai @ 2019-06-24  9:34 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, 坚定前行,
	Maxime Ripard, linux-kernel, dri-devel, David Airlie,
	linux-sunxi, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

Hi,

On Mon, May 20, 2019 at 5:07 PM Jagan Teki <jagan@amarulasolutions.com> wrote:
>
> start value in video start delay computation done in below commit
> is as per the legacy bsp drivers/video/sunxi/legacy..
> "drm/sun4i: dsi: Change the start delay calculation"
> (sha1: da676c6aa6413d59ab0a80c97bbc273025e640b2)

There is a standard format for referencing commits. Please use it.
The format is:

    ... commit <leading 12 characters of commit hash> ("commit subject") ...

So your commit message should read:

    start value in video start delay was changed in commit
da676c6aa641 ("drm/sun4i:
    dsi: Change the start delay calculation") to match the legacy BSP
driver [1].

>
> This existing start delay computation gives start value of 35,
> for "bananapi,s070wv20-ct16" panel timings which indeed trigger
> panel flip_done timed out as:
>
>  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
>  [CRTC:46:crtc-0] vblank wait timed out
>  Modules linked in:
>  CPU: 0 PID: 31 Comm: kworker/0:1 Tainted: G        W         5.1.0-next-20190514-00025-gf928bc7cc146 #15
>  Hardware name: Allwinner sun8i Family
>  Workqueue: events deferred_probe_work_func
>  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
>  [<c010b76c>] (show_stack) from [<c0688c90>] (dump_stack+0x84/0x98)
>  [<c0688c90>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
>  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
>  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
>  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
>  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
>  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
>  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
>  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c0411cb0>] (drm_fb_helper_pan_display+0xac/0x1d0)
>  [<c0411cb0>] (drm_fb_helper_pan_display) from [<c03a4e84>] (fb_pan_display+0xcc/0x134)
>  [<c03a4e84>] (fb_pan_display) from [<c03b1214>] (bit_update_start+0x14/0x30)
>  [<c03b1214>] (bit_update_start) from [<c03afe94>] (fbcon_switch+0x3d8/0x4e0)
>  [<c03afe94>] (fbcon_switch) from [<c03ec930>] (redraw_screen+0x174/0x238)
>  [<c03ec930>] (redraw_screen) from [<c03aceb4>] (fbcon_prepare_logo+0x3c4/0x400)
>  [<c03aceb4>] (fbcon_prepare_logo) from [<c03ad2b8>] (fbcon_init+0x3c8/0x5ac)
>  [<c03ad2b8>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
>  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
>  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
>  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
>  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
>  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
>  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
>  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
>  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
>  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
>  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
>  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
>  [<c043f060>] (sun4i_drv_bind) from [<c044b5b0>] (try_to_bring_up_master+0x164/0x1a0)
>  [<c044b5b0>] (try_to_bring_up_master) from [<c044b680>] (__component_add+0x94/0x140)
>  [<c044b680>] (__component_add) from [<c0445e1c>] (sun6i_dsi_probe+0x144/0x234)
>  [<c0445e1c>] (sun6i_dsi_probe) from [<c0452f0c>] (platform_drv_probe+0x48/0x9c)
>  [<c0452f0c>] (platform_drv_probe) from [<c04512e4>] (really_probe+0x1dc/0x2c8)
>  [<c04512e4>] (really_probe) from [<c0451530>] (driver_probe_device+0x60/0x160)
>  [<c0451530>] (driver_probe_device) from [<c044f7bc>] (bus_for_each_drv+0x74/0xb8)
>  [<c044f7bc>] (bus_for_each_drv) from [<c0451094>] (__device_attach+0xd0/0x13c)
>  [<c0451094>] (__device_attach) from [<c045048c>] (bus_probe_device+0x84/0x8c)
>  [<c045048c>] (bus_probe_device) from [<c0450918>] (deferred_probe_work_func+0x64/0x90)
>  [<c0450918>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
>  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
>  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
>  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
>  Exception stack(0xde539fb0 to 0xde539ff8)
>  9fa0:                                     00000000 00000000 00000000 00000000
>  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
>  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
>  ---[ end trace 755e10f62b83f396 ]---
>  Console: switching to colour frame buffer device 100x30
>  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:46:crtc-0] flip_done timed out
>  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:48:DSI-1] flip_done timed out
>  [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:30:plane-0] flip_done timed out
>
> But the expected start delay value is 1 which is confirmed from
> new bsp [2].
>
> The important and unclear note on legacy and new bsp codes [1] [2]
> is both use similar start computation initially but it later reassign
> it to 1 in new bsp.
>
> Unfortunately we don't have any evidence or documentation for this
> reassignment to 1 in new bsp, but it is working with all supported
> panels in A33, A64.
>
> So, use the start as per new bsp code since it is working in all
> the supported panels.

It would be better to actually list the panels you tested. The list of
"supported panels" is nowhere to be found, and would change from release
to release anyways. It would be hard for anyone to realize which ones
were actually tested.

It would also help if others want to verify your fix, and/or test other
hardware.

Also I suggest following a similar pattern to the suggestions I gave for patch 1
for writing your commit logs:

  1. Describe what you observe to be not working.

     In this case, the display is not working, with the provided traceback
     and kernel logs.

  2. Describe what you think went wrong.

     This could be a git bisect result, or in this case, you are
providing evidence
     from the BSP with links and actual results from hardware running
the BSP. For
     actual running BSP, it would be better to provide the actual
hardware combinations
     you are running on, in addition to the BSP links. Last, the best
piece of concrete
     evidence might be relevant register values from functioning hardware.

  3. Explain that the fix corrects the issue for you, and list the hardware
     that it works on.

  4. Optional. Any other thoughts on the subject matter, such as suspicion of
     other broken hardware, or the fix might not be complete.

> [2] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L807
> [1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/legacy/disp/de_bsp/de/ebios/de_dsi.c#L682

Please list your references in increasing order:

    [1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/legacy/disp/de_bsp/de/ebios/de_dsi.c#L682
    [2] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L807

It is otherwise confusing. I believe Maxime might have mixed up the two.

Otherwise I believe the commit message matches the intent of the code.
I'm afraid I don't know enough about DSI in general or the hardware to
comment on why this works and if it's the right fix though.

Regards,
ChenYu

> Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
> ---
>  drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 12 +++++++++++-
>  1 file changed, 11 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
> index c5bec0096b7c..b3ca85410b2c 100644
> --- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
> +++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
> @@ -364,7 +364,17 @@ static void sun6i_dsi_inst_init(struct sun6i_dsi *dsi,
>  static u16 sun6i_dsi_get_video_start_delay(struct sun6i_dsi *dsi,
>                                            struct drm_display_mode *mode)
>  {
> -       u16 start = clamp(mode->vtotal - mode->vdisplay - 10, 8, 100);
> +       /**
> +        * Allwinner legacy (drivers/video/sunxi/legacy),
> +        * new (drivers/video/sunxi/disp/de/lowlevel_sun8iw5) bsp drivers
> +        * are evaluating start as:
> +        *
> +        *      vtotal - vdisplay - 10
> +        *
> +        * but the new drivers are reassigning start to 1, which seems to be
> +        * working in all supported panels as of now.
> +        */
> +       u8 start = 1;
>         u16 delay = mode->vtotal - (mode->vsync_end - mode->vdisplay) + start;
>
>         if (delay > mode->vtotal)
> --
> 2.18.0.321.gffc6fa0e3
>

_______________________________________________
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linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes
  2019-06-14 12:03             ` Jagan Teki
@ 2019-06-24 13:04               ` Maxime Ripard
  2019-06-24 16:02                 ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-06-24 13:04 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

[-- Attachment #1.1: Type: text/plain, Size: 8665 bytes --]

On Fri, Jun 14, 2019 at 05:33:23PM +0530, Jagan Teki wrote:
> On Thu, Jun 13, 2019 at 7:28 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> >
> > On Wed, Jun 05, 2019 at 01:11:44PM +0530, Jagan Teki wrote:
> > > On Tue, Jun 4, 2019 at 8:00 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > >
> > > > On Fri, May 24, 2019 at 03:37:36PM +0530, Jagan Teki wrote:
> > > > > On Fri, May 24, 2019 at 2:18 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > >
> > > > > > On Mon, May 20, 2019 at 02:33:11PM +0530, Jagan Teki wrote:
> > > > > > > pll-video => pll-mipi => tcon0 => tcon0-pixel-clock is the typical
> > > > > > > MIPI clock topology in Allwinner DSI controller.
> > > > > > >
> > > > > > > TCON dotclock driver is computing the desired DCLK divider based on
> > > > > > > panel pixel clock along with input DCLK min, max divider values from
> > > > > > > tcon driver and that would eventually set the pll-mipi clock rate.
> > > > > > >
> > > > > > > The current code is passing dsi min and max divider value as 4 via
> > > > > > > tcon driver which would ended-up triggering below vblank wait timed out
> > > > > > > warning on "bananapi,s070wv20-ct16" panel.
> > > > > > >
> > > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > > >  Modules linked in:
> > > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00025-g5186cdf10757-dirty #6
> > > > > > >  Hardware name: Allwinner sun8i Family
> > > > > > >  Workqueue: events deferred_probe_work_func
> > > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b588>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > > >  [<c044b588>] (try_to_bring_up_master) from [<c044b658>] (__component_add+0x94/0x140)
> > > > > > >  [<c044b658>] (__component_add) from [<c0445e0c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > > >  [<c0445e0c>] (sun6i_dsi_probe) from [<c0452ee4>] (platform_drv_probe+0x48/0x9c)
> > > > > > >  [<c0452ee4>] (platform_drv_probe) from [<c04512bc>] (really_probe+0x1dc/0x2c8)
> > > > > > >  [<c04512bc>] (really_probe) from [<c0451508>] (driver_probe_device+0x60/0x160)
> > > > > > >  [<c0451508>] (driver_probe_device) from [<c044f794>] (bus_for_each_drv+0x74/0xb8)
> > > > > > >  [<c044f794>] (bus_for_each_drv) from [<c045106c>] (__device_attach+0xd0/0x13c)
> > > > > > >  [<c045106c>] (__device_attach) from [<c0450464>] (bus_probe_device+0x84/0x8c)
> > > > > > >  [<c0450464>] (bus_probe_device) from [<c04508f0>] (deferred_probe_work_func+0x64/0x90)
> > > > > > >  [<c04508f0>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > > >  ---[ end trace 4017fea4906ab391 ]---
> > > > > > >
> > > > > > > But accordingly to Allwinner A33, A64 BSP codes [1] [2] this divider
> > > > > > > is clearly using 'format/lanes' for dsi divider value, dsi_clk.clk_div
> > > > > > >
> > > > > > > Which would compute the pll_freq and set a clock rate for it in
> > > > > > > [3] and [4] respectively.
> > > > > > >
> > > > > > > The same issue has reproduced in A33, A64 with 4-lane and 2-lane devices
> > > > > > > and got fixed with this computation logic 'format/lanes', so this patch
> > > > > > > using dclk min and max dividers as per BSP.
> > > > > > >
> > > > > > > [1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1106
> > > > > > > [2] https://github.com/BPI-SINOVOIP/BPI-M64-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/disp_al.c#L213
> > > > > > > [3] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1127
> > > > > > > [4] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1161
> > > > > >
> > > > > > In that mail, I've pointed out that clk_div isn't used for the TCON dclk divider:
> > > > > > http://lists.infradead.org/pipermail/linux-arm-kernel/2019-February/629596.html
> > > > > >
> > > > > > The only reply you've sent is that you indeed see that the divider is
> > > > > > set to 4 in the BSP, but you're now saying that the BSP can change
> > > > > > it. If so, then please point exactly the flaw in the explanation in
> > > > > > that mail.
> > > > >
> > > > > Frankly, I have explained these details in commit message and previous
> > > > > version patch[1] with print messages on the code.
> > > > >
> > > > > BSP has tcon_div and dsi_div. dsi_div is dynamic which depends on
> > > > > bpp/lanes and it indeed depends on PLL computation (not tcon_div),
> > > > > anyway I have explained again on this initial link you mentioned.
> > > > > Please have a look and get back.
> > > >
> > > > I'll have a look, thanks.
> > > >
> > > > I've given your patches a try on my setup though, and this patch
> > > > breaks it with vblank timeouts and some horizontal lines that looks
> > > > like what should be displayed, but blinking and on the right of the
> > > > display. The previous ones are fine though.
> > >
> > > Would you please send me the link of panel driver.
> >
> > It's drivers/gpu/drm/panel/panel-ronbo-rb070d30.c
>
> Look like this panel work even w/o any vendor sequence. it's similar
> to the 4-lane panel I have with RGB888, so the dclk div is 6, is it
> working with this divider?

It works with 4, it doesn't work with 6.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
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^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes
  2019-06-24 13:04               ` Maxime Ripard
@ 2019-06-24 16:02                 ` Jagan Teki
  2019-06-25 14:37                   ` Maxime Ripard
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-06-24 16:02 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Mon, Jun 24, 2019 at 6:34 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Fri, Jun 14, 2019 at 05:33:23PM +0530, Jagan Teki wrote:
> > On Thu, Jun 13, 2019 at 7:28 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > >
> > > On Wed, Jun 05, 2019 at 01:11:44PM +0530, Jagan Teki wrote:
> > > > On Tue, Jun 4, 2019 at 8:00 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > >
> > > > > On Fri, May 24, 2019 at 03:37:36PM +0530, Jagan Teki wrote:
> > > > > > On Fri, May 24, 2019 at 2:18 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > >
> > > > > > > On Mon, May 20, 2019 at 02:33:11PM +0530, Jagan Teki wrote:
> > > > > > > > pll-video => pll-mipi => tcon0 => tcon0-pixel-clock is the typical
> > > > > > > > MIPI clock topology in Allwinner DSI controller.
> > > > > > > >
> > > > > > > > TCON dotclock driver is computing the desired DCLK divider based on
> > > > > > > > panel pixel clock along with input DCLK min, max divider values from
> > > > > > > > tcon driver and that would eventually set the pll-mipi clock rate.
> > > > > > > >
> > > > > > > > The current code is passing dsi min and max divider value as 4 via
> > > > > > > > tcon driver which would ended-up triggering below vblank wait timed out
> > > > > > > > warning on "bananapi,s070wv20-ct16" panel.
> > > > > > > >
> > > > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > > > >  Modules linked in:
> > > > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00025-g5186cdf10757-dirty #6
> > > > > > > >  Hardware name: Allwinner sun8i Family
> > > > > > > >  Workqueue: events deferred_probe_work_func
> > > > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b588>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > > > >  [<c044b588>] (try_to_bring_up_master) from [<c044b658>] (__component_add+0x94/0x140)
> > > > > > > >  [<c044b658>] (__component_add) from [<c0445e0c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > > > >  [<c0445e0c>] (sun6i_dsi_probe) from [<c0452ee4>] (platform_drv_probe+0x48/0x9c)
> > > > > > > >  [<c0452ee4>] (platform_drv_probe) from [<c04512bc>] (really_probe+0x1dc/0x2c8)
> > > > > > > >  [<c04512bc>] (really_probe) from [<c0451508>] (driver_probe_device+0x60/0x160)
> > > > > > > >  [<c0451508>] (driver_probe_device) from [<c044f794>] (bus_for_each_drv+0x74/0xb8)
> > > > > > > >  [<c044f794>] (bus_for_each_drv) from [<c045106c>] (__device_attach+0xd0/0x13c)
> > > > > > > >  [<c045106c>] (__device_attach) from [<c0450464>] (bus_probe_device+0x84/0x8c)
> > > > > > > >  [<c0450464>] (bus_probe_device) from [<c04508f0>] (deferred_probe_work_func+0x64/0x90)
> > > > > > > >  [<c04508f0>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > > > >  ---[ end trace 4017fea4906ab391 ]---
> > > > > > > >
> > > > > > > > But accordingly to Allwinner A33, A64 BSP codes [1] [2] this divider
> > > > > > > > is clearly using 'format/lanes' for dsi divider value, dsi_clk.clk_div
> > > > > > > >
> > > > > > > > Which would compute the pll_freq and set a clock rate for it in
> > > > > > > > [3] and [4] respectively.
> > > > > > > >
> > > > > > > > The same issue has reproduced in A33, A64 with 4-lane and 2-lane devices
> > > > > > > > and got fixed with this computation logic 'format/lanes', so this patch
> > > > > > > > using dclk min and max dividers as per BSP.
> > > > > > > >
> > > > > > > > [1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1106
> > > > > > > > [2] https://github.com/BPI-SINOVOIP/BPI-M64-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/disp_al.c#L213
> > > > > > > > [3] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1127
> > > > > > > > [4] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1161
> > > > > > >
> > > > > > > In that mail, I've pointed out that clk_div isn't used for the TCON dclk divider:
> > > > > > > http://lists.infradead.org/pipermail/linux-arm-kernel/2019-February/629596.html
> > > > > > >
> > > > > > > The only reply you've sent is that you indeed see that the divider is
> > > > > > > set to 4 in the BSP, but you're now saying that the BSP can change
> > > > > > > it. If so, then please point exactly the flaw in the explanation in
> > > > > > > that mail.
> > > > > >
> > > > > > Frankly, I have explained these details in commit message and previous
> > > > > > version patch[1] with print messages on the code.
> > > > > >
> > > > > > BSP has tcon_div and dsi_div. dsi_div is dynamic which depends on
> > > > > > bpp/lanes and it indeed depends on PLL computation (not tcon_div),
> > > > > > anyway I have explained again on this initial link you mentioned.
> > > > > > Please have a look and get back.
> > > > >
> > > > > I'll have a look, thanks.
> > > > >
> > > > > I've given your patches a try on my setup though, and this patch
> > > > > breaks it with vblank timeouts and some horizontal lines that looks
> > > > > like what should be displayed, but blinking and on the right of the
> > > > > display. The previous ones are fine though.
> > > >
> > > > Would you please send me the link of panel driver.
> > >
> > > It's drivers/gpu/drm/panel/panel-ronbo-rb070d30.c
> >
> > Look like this panel work even w/o any vendor sequence. it's similar
> > to the 4-lane panel I have with RGB888, so the dclk div is 6, is it
> > working with this divider?
>
> It works with 4, it doesn't work with 6.

Can be the pixel clock with associated timings can make this diff.
Would you send me the pixel clock, pll_rate and timings this panel
used it from BSP?

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes
  2019-06-24 16:02                 ` Jagan Teki
@ 2019-06-25 14:37                   ` Maxime Ripard
  2019-07-01 19:00                     ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-06-25 14:37 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

[-- Attachment #1.1: Type: text/plain, Size: 9482 bytes --]

On Mon, Jun 24, 2019 at 09:32:11PM +0530, Jagan Teki wrote:
> On Mon, Jun 24, 2019 at 6:34 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> >
> > On Fri, Jun 14, 2019 at 05:33:23PM +0530, Jagan Teki wrote:
> > > On Thu, Jun 13, 2019 at 7:28 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > >
> > > > On Wed, Jun 05, 2019 at 01:11:44PM +0530, Jagan Teki wrote:
> > > > > On Tue, Jun 4, 2019 at 8:00 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > >
> > > > > > On Fri, May 24, 2019 at 03:37:36PM +0530, Jagan Teki wrote:
> > > > > > > On Fri, May 24, 2019 at 2:18 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > >
> > > > > > > > On Mon, May 20, 2019 at 02:33:11PM +0530, Jagan Teki wrote:
> > > > > > > > > pll-video => pll-mipi => tcon0 => tcon0-pixel-clock is the typical
> > > > > > > > > MIPI clock topology in Allwinner DSI controller.
> > > > > > > > >
> > > > > > > > > TCON dotclock driver is computing the desired DCLK divider based on
> > > > > > > > > panel pixel clock along with input DCLK min, max divider values from
> > > > > > > > > tcon driver and that would eventually set the pll-mipi clock rate.
> > > > > > > > >
> > > > > > > > > The current code is passing dsi min and max divider value as 4 via
> > > > > > > > > tcon driver which would ended-up triggering below vblank wait timed out
> > > > > > > > > warning on "bananapi,s070wv20-ct16" panel.
> > > > > > > > >
> > > > > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > > > > >  Modules linked in:
> > > > > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00025-g5186cdf10757-dirty #6
> > > > > > > > >  Hardware name: Allwinner sun8i Family
> > > > > > > > >  Workqueue: events deferred_probe_work_func
> > > > > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > > > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > > > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > > > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > > > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b588>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > > > > >  [<c044b588>] (try_to_bring_up_master) from [<c044b658>] (__component_add+0x94/0x140)
> > > > > > > > >  [<c044b658>] (__component_add) from [<c0445e0c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > > > > >  [<c0445e0c>] (sun6i_dsi_probe) from [<c0452ee4>] (platform_drv_probe+0x48/0x9c)
> > > > > > > > >  [<c0452ee4>] (platform_drv_probe) from [<c04512bc>] (really_probe+0x1dc/0x2c8)
> > > > > > > > >  [<c04512bc>] (really_probe) from [<c0451508>] (driver_probe_device+0x60/0x160)
> > > > > > > > >  [<c0451508>] (driver_probe_device) from [<c044f794>] (bus_for_each_drv+0x74/0xb8)
> > > > > > > > >  [<c044f794>] (bus_for_each_drv) from [<c045106c>] (__device_attach+0xd0/0x13c)
> > > > > > > > >  [<c045106c>] (__device_attach) from [<c0450464>] (bus_probe_device+0x84/0x8c)
> > > > > > > > >  [<c0450464>] (bus_probe_device) from [<c04508f0>] (deferred_probe_work_func+0x64/0x90)
> > > > > > > > >  [<c04508f0>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > > > > >  ---[ end trace 4017fea4906ab391 ]---
> > > > > > > > >
> > > > > > > > > But accordingly to Allwinner A33, A64 BSP codes [1] [2] this divider
> > > > > > > > > is clearly using 'format/lanes' for dsi divider value, dsi_clk.clk_div
> > > > > > > > >
> > > > > > > > > Which would compute the pll_freq and set a clock rate for it in
> > > > > > > > > [3] and [4] respectively.
> > > > > > > > >
> > > > > > > > > The same issue has reproduced in A33, A64 with 4-lane and 2-lane devices
> > > > > > > > > and got fixed with this computation logic 'format/lanes', so this patch
> > > > > > > > > using dclk min and max dividers as per BSP.
> > > > > > > > >
> > > > > > > > > [1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1106
> > > > > > > > > [2] https://github.com/BPI-SINOVOIP/BPI-M64-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/disp_al.c#L213
> > > > > > > > > [3] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1127
> > > > > > > > > [4] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1161
> > > > > > > >
> > > > > > > > In that mail, I've pointed out that clk_div isn't used for the TCON dclk divider:
> > > > > > > > http://lists.infradead.org/pipermail/linux-arm-kernel/2019-February/629596.html
> > > > > > > >
> > > > > > > > The only reply you've sent is that you indeed see that the divider is
> > > > > > > > set to 4 in the BSP, but you're now saying that the BSP can change
> > > > > > > > it. If so, then please point exactly the flaw in the explanation in
> > > > > > > > that mail.
> > > > > > >
> > > > > > > Frankly, I have explained these details in commit message and previous
> > > > > > > version patch[1] with print messages on the code.
> > > > > > >
> > > > > > > BSP has tcon_div and dsi_div. dsi_div is dynamic which depends on
> > > > > > > bpp/lanes and it indeed depends on PLL computation (not tcon_div),
> > > > > > > anyway I have explained again on this initial link you mentioned.
> > > > > > > Please have a look and get back.
> > > > > >
> > > > > > I'll have a look, thanks.
> > > > > >
> > > > > > I've given your patches a try on my setup though, and this patch
> > > > > > breaks it with vblank timeouts and some horizontal lines that looks
> > > > > > like what should be displayed, but blinking and on the right of the
> > > > > > display. The previous ones are fine though.
> > > > >
> > > > > Would you please send me the link of panel driver.
> > > >
> > > > It's drivers/gpu/drm/panel/panel-ronbo-rb070d30.c
> > >
> > > Look like this panel work even w/o any vendor sequence. it's similar
> > > to the 4-lane panel I have with RGB888, so the dclk div is 6, is it
> > > working with this divider?
> >
> > It works with 4, it doesn't work with 6.
>
> Can be the pixel clock with associated timings can make this diff.
> Would you send me the pixel clock, pll_rate and timings this panel
> used it from BSP?

This board never had an Allwinner BSP

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes
  2019-06-25 14:37                   ` Maxime Ripard
@ 2019-07-01 19:00                     ` Jagan Teki
  2019-07-02 15:29                       ` Maxime Ripard
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-07-01 19:00 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Tue, Jun 25, 2019 at 8:07 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Mon, Jun 24, 2019 at 09:32:11PM +0530, Jagan Teki wrote:
> > On Mon, Jun 24, 2019 at 6:34 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > >
> > > On Fri, Jun 14, 2019 at 05:33:23PM +0530, Jagan Teki wrote:
> > > > On Thu, Jun 13, 2019 at 7:28 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > >
> > > > > On Wed, Jun 05, 2019 at 01:11:44PM +0530, Jagan Teki wrote:
> > > > > > On Tue, Jun 4, 2019 at 8:00 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > >
> > > > > > > On Fri, May 24, 2019 at 03:37:36PM +0530, Jagan Teki wrote:
> > > > > > > > On Fri, May 24, 2019 at 2:18 AM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > >
> > > > > > > > > On Mon, May 20, 2019 at 02:33:11PM +0530, Jagan Teki wrote:
> > > > > > > > > > pll-video => pll-mipi => tcon0 => tcon0-pixel-clock is the typical
> > > > > > > > > > MIPI clock topology in Allwinner DSI controller.
> > > > > > > > > >
> > > > > > > > > > TCON dotclock driver is computing the desired DCLK divider based on
> > > > > > > > > > panel pixel clock along with input DCLK min, max divider values from
> > > > > > > > > > tcon driver and that would eventually set the pll-mipi clock rate.
> > > > > > > > > >
> > > > > > > > > > The current code is passing dsi min and max divider value as 4 via
> > > > > > > > > > tcon driver which would ended-up triggering below vblank wait timed out
> > > > > > > > > > warning on "bananapi,s070wv20-ct16" panel.
> > > > > > > > > >
> > > > > > > > > >  WARNING: CPU: 0 PID: 31 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > > > > > > > > >  [CRTC:46:crtc-0] vblank wait timed out
> > > > > > > > > >  Modules linked in:
> > > > > > > > > >  CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted 5.1.0-next-20190514-00025-g5186cdf10757-dirty #6
> > > > > > > > > >  Hardware name: Allwinner sun8i Family
> > > > > > > > > >  Workqueue: events deferred_probe_work_func
> > > > > > > > > >  [<c010ed54>] (unwind_backtrace) from [<c010b76c>] (show_stack+0x10/0x14)
> > > > > > > > > >  [<c010b76c>] (show_stack) from [<c0688c70>] (dump_stack+0x84/0x98)
> > > > > > > > > >  [<c0688c70>] (dump_stack) from [<c011d9e4>] (__warn+0xfc/0x114)
> > > > > > > > > >  [<c011d9e4>] (__warn) from [<c011da40>] (warn_slowpath_fmt+0x44/0x68)
> > > > > > > > > >  [<c011da40>] (warn_slowpath_fmt) from [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > > > > > > > > >  [<c040cd50>] (drm_atomic_helper_wait_for_vblanks.part.1) from [<c040e694>] (drm_atomic_helper_commit_tail_rpm+0x5c/0x6c)
> > > > > > > > > >  [<c040e694>] (drm_atomic_helper_commit_tail_rpm) from [<c040e4dc>] (commit_tail+0x40/0x6c)
> > > > > > > > > >  [<c040e4dc>] (commit_tail) from [<c040e5cc>] (drm_atomic_helper_commit+0xbc/0x128)
> > > > > > > > > >  [<c040e5cc>] (drm_atomic_helper_commit) from [<c0411b64>] (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > > > > > > > > >  [<c0411b64>] (restore_fbdev_mode_atomic) from [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > > > > > > > > >  [<c04156f8>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c0415774>] (drm_fb_helper_set_par+0x30/0x54)
> > > > > > > > > >  [<c0415774>] (drm_fb_helper_set_par) from [<c03ad450>] (fbcon_init+0x560/0x5ac)
> > > > > > > > > >  [<c03ad450>] (fbcon_init) from [<c03eb8a0>] (visual_init+0xbc/0x104)
> > > > > > > > > >  [<c03eb8a0>] (visual_init) from [<c03ed1b8>] (do_bind_con_driver+0x1b0/0x390)
> > > > > > > > > >  [<c03ed1b8>] (do_bind_con_driver) from [<c03ed780>] (do_take_over_console+0x13c/0x1c4)
> > > > > > > > > >  [<c03ed780>] (do_take_over_console) from [<c03ad800>] (do_fbcon_takeover+0x74/0xcc)
> > > > > > > > > >  [<c03ad800>] (do_fbcon_takeover) from [<c013c9c8>] (notifier_call_chain+0x44/0x84)
> > > > > > > > > >  [<c013c9c8>] (notifier_call_chain) from [<c013cd20>] (__blocking_notifier_call_chain+0x48/0x60)
> > > > > > > > > >  [<c013cd20>] (__blocking_notifier_call_chain) from [<c013cd50>] (blocking_notifier_call_chain+0x18/0x20)
> > > > > > > > > >  [<c013cd50>] (blocking_notifier_call_chain) from [<c03a6e44>] (register_framebuffer+0x1e0/0x2f8)
> > > > > > > > > >  [<c03a6e44>] (register_framebuffer) from [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock+0x2fc/0x50c)
> > > > > > > > > >  [<c04153c0>] (__drm_fb_helper_initial_config_and_unlock) from [<c04158c8>] (drm_fbdev_client_hotplug+0xe8/0x1b8)
> > > > > > > > > >  [<c04158c8>] (drm_fbdev_client_hotplug) from [<c0415a20>] (drm_fbdev_generic_setup+0x88/0x118)
> > > > > > > > > >  [<c0415a20>] (drm_fbdev_generic_setup) from [<c043f060>] (sun4i_drv_bind+0x128/0x160)
> > > > > > > > > >  [<c043f060>] (sun4i_drv_bind) from [<c044b588>] (try_to_bring_up_master+0x164/0x1a0)
> > > > > > > > > >  [<c044b588>] (try_to_bring_up_master) from [<c044b658>] (__component_add+0x94/0x140)
> > > > > > > > > >  [<c044b658>] (__component_add) from [<c0445e0c>] (sun6i_dsi_probe+0x144/0x234)
> > > > > > > > > >  [<c0445e0c>] (sun6i_dsi_probe) from [<c0452ee4>] (platform_drv_probe+0x48/0x9c)
> > > > > > > > > >  [<c0452ee4>] (platform_drv_probe) from [<c04512bc>] (really_probe+0x1dc/0x2c8)
> > > > > > > > > >  [<c04512bc>] (really_probe) from [<c0451508>] (driver_probe_device+0x60/0x160)
> > > > > > > > > >  [<c0451508>] (driver_probe_device) from [<c044f794>] (bus_for_each_drv+0x74/0xb8)
> > > > > > > > > >  [<c044f794>] (bus_for_each_drv) from [<c045106c>] (__device_attach+0xd0/0x13c)
> > > > > > > > > >  [<c045106c>] (__device_attach) from [<c0450464>] (bus_probe_device+0x84/0x8c)
> > > > > > > > > >  [<c0450464>] (bus_probe_device) from [<c04508f0>] (deferred_probe_work_func+0x64/0x90)
> > > > > > > > > >  [<c04508f0>] (deferred_probe_work_func) from [<c0135970>] (process_one_work+0x204/0x420)
> > > > > > > > > >  [<c0135970>] (process_one_work) from [<c013690c>] (worker_thread+0x274/0x5a0)
> > > > > > > > > >  [<c013690c>] (worker_thread) from [<c013b3d8>] (kthread+0x11c/0x14c)
> > > > > > > > > >  [<c013b3d8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> > > > > > > > > >  Exception stack(0xde539fb0 to 0xde539ff8)
> > > > > > > > > >  9fa0:                                     00000000 00000000 00000000 00000000
> > > > > > > > > >  9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > > > > > > > > >  9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > > > > > > > > >  ---[ end trace 4017fea4906ab391 ]---
> > > > > > > > > >
> > > > > > > > > > But accordingly to Allwinner A33, A64 BSP codes [1] [2] this divider
> > > > > > > > > > is clearly using 'format/lanes' for dsi divider value, dsi_clk.clk_div
> > > > > > > > > >
> > > > > > > > > > Which would compute the pll_freq and set a clock rate for it in
> > > > > > > > > > [3] and [4] respectively.
> > > > > > > > > >
> > > > > > > > > > The same issue has reproduced in A33, A64 with 4-lane and 2-lane devices
> > > > > > > > > > and got fixed with this computation logic 'format/lanes', so this patch
> > > > > > > > > > using dclk min and max dividers as per BSP.
> > > > > > > > > >
> > > > > > > > > > [1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1106
> > > > > > > > > > [2] https://github.com/BPI-SINOVOIP/BPI-M64-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/disp_al.c#L213
> > > > > > > > > > [3] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1127
> > > > > > > > > > [4] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/disp_lcd.c#L1161
> > > > > > > > >
> > > > > > > > > In that mail, I've pointed out that clk_div isn't used for the TCON dclk divider:
> > > > > > > > > http://lists.infradead.org/pipermail/linux-arm-kernel/2019-February/629596.html
> > > > > > > > >
> > > > > > > > > The only reply you've sent is that you indeed see that the divider is
> > > > > > > > > set to 4 in the BSP, but you're now saying that the BSP can change
> > > > > > > > > it. If so, then please point exactly the flaw in the explanation in
> > > > > > > > > that mail.
> > > > > > > >
> > > > > > > > Frankly, I have explained these details in commit message and previous
> > > > > > > > version patch[1] with print messages on the code.
> > > > > > > >
> > > > > > > > BSP has tcon_div and dsi_div. dsi_div is dynamic which depends on
> > > > > > > > bpp/lanes and it indeed depends on PLL computation (not tcon_div),
> > > > > > > > anyway I have explained again on this initial link you mentioned.
> > > > > > > > Please have a look and get back.
> > > > > > >
> > > > > > > I'll have a look, thanks.
> > > > > > >
> > > > > > > I've given your patches a try on my setup though, and this patch
> > > > > > > breaks it with vblank timeouts and some horizontal lines that looks
> > > > > > > like what should be displayed, but blinking and on the right of the
> > > > > > > display. The previous ones are fine though.
> > > > > >
> > > > > > Would you please send me the link of panel driver.
> > > > >
> > > > > It's drivers/gpu/drm/panel/panel-ronbo-rb070d30.c
> > > >
> > > > Look like this panel work even w/o any vendor sequence. it's similar
> > > > to the 4-lane panel I have with RGB888, so the dclk div is 6, is it
> > > > working with this divider?
> > >
> > > It works with 4, it doesn't work with 6.
> >
> > Can be the pixel clock with associated timings can make this diff.
> > Would you send me the pixel clock, pll_rate and timings this panel
> > used it from BSP?
>
> This board never had an Allwinner BSP

Running on BSP would help to understand some clue, anyway would you
send me the the value PLL_MIPI register (devme 0x1c20040) on this
board. I'm trying to understand how it value in your case.

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes
  2019-07-01 19:00                     ` Jagan Teki
@ 2019-07-02 15:29                       ` Maxime Ripard
  2019-07-02 15:40                         ` Jagan Teki
  0 siblings, 1 reply; 54+ messages in thread
From: Maxime Ripard @ 2019-07-02 15:29 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Tue, Jul 02, 2019 at 12:30:14AM +0530, Jagan Teki wrote:
> On Tue, Jun 25, 2019 at 8:07 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > > BSP has tcon_div and dsi_div. dsi_div is dynamic which depends on
> > > > > > > > > bpp/lanes and it indeed depends on PLL computation (not tcon_div),
> > > > > > > > > anyway I have explained again on this initial link you mentioned.
> > > > > > > > > Please have a look and get back.
> > > > > > > >
> > > > > > > > I'll have a look, thanks.
> > > > > > > >
> > > > > > > > I've given your patches a try on my setup though, and this patch
> > > > > > > > breaks it with vblank timeouts and some horizontal lines that looks
> > > > > > > > like what should be displayed, but blinking and on the right of the
> > > > > > > > display. The previous ones are fine though.
> > > > > > >
> > > > > > > Would you please send me the link of panel driver.
> > > > > >
> > > > > > It's drivers/gpu/drm/panel/panel-ronbo-rb070d30.c
> > > > >
> > > > > Look like this panel work even w/o any vendor sequence. it's similar
> > > > > to the 4-lane panel I have with RGB888, so the dclk div is 6, is it
> > > > > working with this divider?
> > > >
> > > > It works with 4, it doesn't work with 6.
> > >
> > > Can be the pixel clock with associated timings can make this diff.
> > > Would you send me the pixel clock, pll_rate and timings this panel
> > > used it from BSP?
> >
> > This board never had an Allwinner BSP
>
> Running on BSP would help to understand some clue, anyway would you
> send me the the value PLL_MIPI register (devme 0x1c20040) on this
> board. I'm trying to understand how it value in your case.

I'm sorry, but I'm not going to port a whole BSP on that board,
especially for something I haven't been convinced it's the right fix.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes
  2019-07-02 15:29                       ` Maxime Ripard
@ 2019-07-02 15:40                         ` Jagan Teki
  2019-07-03 11:51                           ` Maxime Ripard
  0 siblings, 1 reply; 54+ messages in thread
From: Jagan Teki @ 2019-07-02 15:40 UTC (permalink / raw)
  To: Maxime Ripard
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

On Tue, Jul 2, 2019 at 8:59 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Tue, Jul 02, 2019 at 12:30:14AM +0530, Jagan Teki wrote:
> > On Tue, Jun 25, 2019 at 8:07 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > > > BSP has tcon_div and dsi_div. dsi_div is dynamic which depends on
> > > > > > > > > > bpp/lanes and it indeed depends on PLL computation (not tcon_div),
> > > > > > > > > > anyway I have explained again on this initial link you mentioned.
> > > > > > > > > > Please have a look and get back.
> > > > > > > > >
> > > > > > > > > I'll have a look, thanks.
> > > > > > > > >
> > > > > > > > > I've given your patches a try on my setup though, and this patch
> > > > > > > > > breaks it with vblank timeouts and some horizontal lines that looks
> > > > > > > > > like what should be displayed, but blinking and on the right of the
> > > > > > > > > display. The previous ones are fine though.
> > > > > > > >
> > > > > > > > Would you please send me the link of panel driver.
> > > > > > >
> > > > > > > It's drivers/gpu/drm/panel/panel-ronbo-rb070d30.c
> > > > > >
> > > > > > Look like this panel work even w/o any vendor sequence. it's similar
> > > > > > to the 4-lane panel I have with RGB888, so the dclk div is 6, is it
> > > > > > working with this divider?
> > > > >
> > > > > It works with 4, it doesn't work with 6.
> > > >
> > > > Can be the pixel clock with associated timings can make this diff.
> > > > Would you send me the pixel clock, pll_rate and timings this panel
> > > > used it from BSP?
> > >
> > > This board never had an Allwinner BSP
> >
> > Running on BSP would help to understand some clue, anyway would you
> > send me the the value PLL_MIPI register (devme 0x1c20040) on this
> > board. I'm trying to understand how it value in your case.
>
> I'm sorry, but I'm not going to port a whole BSP on that board,
> especially for something I haven't been convinced it's the right fix.

Look like a dead lock here, this change has a conclusive evidence from
BSP (which is AW datasheet or open code to outside world) and it is
working with A33, A64 and R40 which was tested in 4 different panels
and I don't understand the reason for not going with this (atleast
check with respect to BSP).

Please suggest, what I can do further, your suggestion is very helpful here.

Jagan.

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 54+ messages in thread

* Re: [linux-sunxi] Re: [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes
  2019-07-02 15:40                         ` Jagan Teki
@ 2019-07-03 11:51                           ` Maxime Ripard
  0 siblings, 0 replies; 54+ messages in thread
From: Maxime Ripard @ 2019-07-03 11:51 UTC (permalink / raw)
  To: Jagan Teki
  Cc: Bhushan Shah, David Airlie, linux-sunxi, linux-kernel, dri-devel,
	坚定前行,
	Chen-Yu Tsai, Daniel Vetter, Michael Trimarchi, linux-amarula,
	linux-arm-kernel

[-- Attachment #1.1: Type: text/plain, Size: 2668 bytes --]

On Tue, Jul 02, 2019 at 09:10:26PM +0530, Jagan Teki wrote:
> On Tue, Jul 2, 2019 at 8:59 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > On Tue, Jul 02, 2019 at 12:30:14AM +0530, Jagan Teki wrote:
> > > On Tue, Jun 25, 2019 at 8:07 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
> > > > > > > > > > > BSP has tcon_div and dsi_div. dsi_div is dynamic which depends on
> > > > > > > > > > > bpp/lanes and it indeed depends on PLL computation (not tcon_div),
> > > > > > > > > > > anyway I have explained again on this initial link you mentioned.
> > > > > > > > > > > Please have a look and get back.
> > > > > > > > > >
> > > > > > > > > > I'll have a look, thanks.
> > > > > > > > > >
> > > > > > > > > > I've given your patches a try on my setup though, and this patch
> > > > > > > > > > breaks it with vblank timeouts and some horizontal lines that looks
> > > > > > > > > > like what should be displayed, but blinking and on the right of the
> > > > > > > > > > display. The previous ones are fine though.
> > > > > > > > >
> > > > > > > > > Would you please send me the link of panel driver.
> > > > > > > >
> > > > > > > > It's drivers/gpu/drm/panel/panel-ronbo-rb070d30.c
> > > > > > >
> > > > > > > Look like this panel work even w/o any vendor sequence. it's similar
> > > > > > > to the 4-lane panel I have with RGB888, so the dclk div is 6, is it
> > > > > > > working with this divider?
> > > > > >
> > > > > > It works with 4, it doesn't work with 6.
> > > > >
> > > > > Can be the pixel clock with associated timings can make this diff.
> > > > > Would you send me the pixel clock, pll_rate and timings this panel
> > > > > used it from BSP?
> > > >
> > > > This board never had an Allwinner BSP
> > >
> > > Running on BSP would help to understand some clue, anyway would you
> > > send me the the value PLL_MIPI register (devme 0x1c20040) on this
> > > board. I'm trying to understand how it value in your case.
> >
> > I'm sorry, but I'm not going to port a whole BSP on that board,
> > especially for something I haven't been convinced it's the right fix.
>
> Look like a dead lock here, this change has a conclusive evidence from
> BSP (which is AW datasheet or open code to outside world) and it is
> working with A33, A64 and R40 which was tested in 4 different panels
> and I don't understand the reason for not going with this (atleast
> check with respect to BSP).

Because that would take a month or so?

> Please suggest, what I can do further, your suggestion is very
> helpful here.

I already did, and you ignored it. Several times.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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[-- Attachment #2: Type: text/plain, Size: 176 bytes --]

_______________________________________________
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^ permalink raw reply	[flat|nested] 54+ messages in thread

end of thread, back to index

Thread overview: 54+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-05-20  9:03 [PATCH v10 00/11] drm/sun4i: dsi: Fixes/updates (A33 reworked!) Jagan Teki
2019-05-20  9:03 ` [PATCH v10 01/11] drm/sun4i: dsi: Fix TCON DRQ set bits Jagan Teki
2019-05-23 20:34   ` Maxime Ripard
2019-05-24 10:18     ` Jagan Teki
2019-05-29 14:54       ` Maxime Ripard
2019-05-29 18:14         ` Jagan Teki
2019-06-04 10:00           ` Maxime Ripard
2019-06-05  7:47             ` Jagan Teki
2019-06-13 12:56               ` Maxime Ripard
2019-06-14  6:33                 ` Jagan Teki
2019-06-14 14:45                   ` Maxime Ripard
2019-06-18 10:51                     ` Jagan Teki
2019-06-18 11:43                       ` [linux-sunxi] " Chen-Yu Tsai
2019-06-18 12:11                         ` Jagan Teki
2019-06-18 14:45                           ` Chen-Yu Tsai
2019-06-20 18:51                             ` Jagan Teki
2019-06-21  3:13                               ` Chen-Yu Tsai
2019-05-20  9:03 ` [PATCH v10 02/11] drm/sun4i: dsi: Update start value in video start delay Jagan Teki
2019-05-23 20:37   ` Maxime Ripard
2019-05-24 10:25     ` Jagan Teki
2019-05-30 10:42       ` Maxime Ripard
2019-06-13  8:04         ` Jagan Teki
2019-06-14 14:28           ` Maxime Ripard
2019-06-18 11:02             ` Jagan Teki
2019-06-24  9:34   ` Chen-Yu Tsai
2019-05-20  9:03 ` [PATCH v10 03/11] drm/sun4i: dsi: Fix video start delay computation Jagan Teki
2019-05-23 20:38   ` Maxime Ripard
2019-05-24 10:26     ` Jagan Teki
2019-06-21  8:35       ` [linux-sunxi] " Chen-Yu Tsai
2019-06-24  8:52         ` Jagan Teki
2019-05-20  9:03 ` [PATCH v10 04/11] drm/sun4i: tcon: Compute DCLK dividers based on format, lanes Jagan Teki
2019-05-23 20:48   ` Maxime Ripard
2019-05-24 10:07     ` Jagan Teki
2019-06-04 14:30       ` Maxime Ripard
2019-06-05  7:41         ` [linux-sunxi] " Jagan Teki
2019-06-13 13:16           ` Maxime Ripard
2019-06-14 12:03             ` Jagan Teki
2019-06-24 13:04               ` Maxime Ripard
2019-06-24 16:02                 ` Jagan Teki
2019-06-25 14:37                   ` Maxime Ripard
2019-07-01 19:00                     ` Jagan Teki
2019-07-02 15:29                       ` Maxime Ripard
2019-07-02 15:40                         ` Jagan Teki
2019-07-03 11:51                           ` Maxime Ripard
2019-05-20  9:03 ` [PATCH v10 05/11] drm/sun4i: tcon: Export get tcon0 routine Jagan Teki
2019-05-20  9:03 ` [PATCH v10 06/11] drm/sun4i: dsi: Probe tcon0 during dsi_bind Jagan Teki
2019-05-20  9:03 ` [PATCH v10 07/11] drm/sun4i: dsi: Get tcon0_div at runtime Jagan Teki
2019-05-20  9:03 ` [PATCH v10 08/11] dt-bindings: sun6i-dsi: Add VCC-DSI supply property Jagan Teki
2019-05-20  9:03 ` [PATCH v10 09/11] drm/sun4i: sun6i_mipi_dsi: Add VCC-DSI regulator support Jagan Teki
2019-06-03 13:49   ` Maxime Ripard
2019-06-13  7:55     ` Jagan Teki
2019-06-13 13:14       ` Maxime Ripard
2019-05-20  9:03 ` [DO NOT MERGE] [PATCH v10 10/11] drm/panel: Add Bananapi S070WV20-CT16 ICN6211 MIPI-DSI to RGB bridge Jagan Teki
2019-05-20  9:03 ` [DO NOT MERGE] [PATCH v10 11/11] ARM: dts: sun8i: bananapi-m2m: Enable Bananapi S070WV20-CT16 DSI panel Jagan Teki

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