[PATCH v5 0/6] drm: lcdif: Add i.MX93 LCDIF support

[PATCH v5 0/6] drm: lcdif: Add i.MX93 LCDIF support

[Liu Ying]

Hi,

This patch set aims to add i.MX93 LCDIF display controller support
in the existing LCDIF DRM driver.  The LCDIF embedded in i.MX93 SoC
is essentially the same to those embedded in i.MX8mp SoC.  Through
internal bridges, i.MX93 LCDIF may drive a MIPI DSI display or a LVDS
display or a parallel display.

Patch 1/6 adds device tree binding support for i.MX93 LCDIF in the
existing fsl,lcdif.yaml.

Patch 2/6 drops lcdif->bridge NULL pointer check as a cleanup patch.

Patch 3/6~5/6 prepare for adding i.MX93 LCDIF support step by step.

Patch 6/6 adds i.MX93 LCDIF compatible string as the last step of
adding i.MX93 LCDIF support.

v4->v5:
* Rebase this patch set upon v6.4-rc1 and resolve a trivial conflict for
  patch 5/6.
* Collect Alexander's R-b tag on patch 3/6, A-b tags on patch 4/6 and 5/6,
  T-b tags on patch 2/6~6/6.

v3->v4:
* Improve warning message when ignoring invalid LCDIF OF endpoint ids in
  patch 5/6. (Alexander)
* Use 'new_{c,p}state' instead of 'new_{crtc,plane}_state' in patch 3/6.
  (Alexander)
* Simplify lcdif_crtc_reset() by calling lcdif_crtc_atomic_destroy_state()
  in patch 3/6. (Alexander)
* Add '!crtc->state' check in lcdif_crtc_atomic_duplicate_state() in patch 3/6.
  (Alexander)
* Collect Alexander's R-b tags on patch 1/6, 2/6 and 6/6.

v2->v3:
* Fix a trivial typo in patch 6/6's commit message.

v1->v2:
* Add Krzysztof's A-b and Marek's R-b tags on patch 1/6.
* Split patch 2/2 in v1 into patch 2/6~6/6 in v2. (Marek, Alexander)
* Drop '!remote ||' from lcdif_attach_bridge(). (Lothar)
* Add comment on the 'base' member of lcdif_crtc_state structure to
  note it should always be the first member. (Lothar)
* Drop unneeded 'bridges' member from lcdif_drm_private structure.
* Drop a comment about bridge input bus format from lcdif_crtc_atomic_check().

Liu Ying (6):
  dt-bindings: lcdif: Add i.MX93 LCDIF support
  drm: lcdif: Drop unnecessary NULL pointer check on lcdif->bridge
  drm: lcdif: Determine bus format and flags in ->atomic_check()
  drm: lcdif: Check consistent bus format and flags across first bridges
  drm: lcdif: Add multiple encoders and first bridges support
  drm: lcdif: Add i.MX93 LCDIF compatible string

 .../bindings/display/fsl,lcdif.yaml           |   7 +-
 drivers/gpu/drm/mxsfb/lcdif_drv.c             |  71 ++++++-
 drivers/gpu/drm/mxsfb/lcdif_drv.h             |   5 +-
 drivers/gpu/drm/mxsfb/lcdif_kms.c             | 198 ++++++++++++------
 4 files changed, 206 insertions(+), 75 deletions(-)

-- 
2.37.1

[PATCH v5 1/6] dt-bindings: lcdif: Add i.MX93 LCDIF support

[Liu Ying]

There is one LCDIF embedded in i.MX93 SoC to connect with
MIPI DSI controller through LCDIF cross line pattern(controlled
by mediamix blk-ctrl) or connect with LVDS display bridge(LDB)
directly or connect with a parallel display through parallel
display format(also controlled by mediamix blk-ctrl).  i.MX93
LCDIF IP is essentially the same to i.MX8MP LCDIF IP.  Add device
tree binding for i.MX93 LCDIF.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Marek Vasut <marex@denx.de>
Reviewed-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
v4->v5:
* No change.

v3->v4:
* Add Alexander's R-b tag.

v2->v3:
* No change.

v1->v2:
* Add Krzysztof's A-b and Marek's R-b tags.

 Documentation/devicetree/bindings/display/fsl,lcdif.yaml | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
index 75b4efd70ba8..fc11ab5fc465 100644
--- a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
+++ b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
@@ -21,6 +21,7 @@ properties:
           - fsl,imx28-lcdif
           - fsl,imx6sx-lcdif
           - fsl,imx8mp-lcdif
+          - fsl,imx93-lcdif
       - items:
           - enum:
               - fsl,imx6sl-lcdif
@@ -88,7 +89,9 @@ allOf:
       properties:
         compatible:
           contains:
-            const: fsl,imx8mp-lcdif
+            enum:
+              - fsl,imx8mp-lcdif
+              - fsl,imx93-lcdif
     then:
       properties:
         clocks:
@@ -107,6 +110,7 @@ allOf:
               enum:
                 - fsl,imx6sx-lcdif
                 - fsl,imx8mp-lcdif
+                - fsl,imx93-lcdif
     then:
       properties:
         clocks:
@@ -123,6 +127,7 @@ allOf:
               - fsl,imx8mm-lcdif
               - fsl,imx8mn-lcdif
               - fsl,imx8mp-lcdif
+              - fsl,imx93-lcdif
     then:
       required:
         - power-domains
-- 
2.37.1

[PATCH v5 2/6] drm: lcdif: Drop unnecessary NULL pointer check on lcdif->bridge

[Liu Ying]

A valid bridge is already found in lcdif_attach_bridge() and set
to lcdif->bridge, so lcdif->bridge cannot be a NULL pointer. Drop
the unnecessary NULL pointer check in KMS stage.

Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
v4->v5:
* Add Alexander's T-b tag.

v3->v4:
* Add Alexander's R-b tag.

v2->v3:
* No change.

v1->v2:
* Split from patch 2/2 in v1. (Marek, Alexander)

 drivers/gpu/drm/mxsfb/lcdif_kms.c | 33 +++++++++++--------------------
 1 file changed, 12 insertions(+), 21 deletions(-)

diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
index 262bc43b1079..e54200a9fcb9 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
@@ -394,7 +394,7 @@ static void lcdif_crtc_mode_set_nofb(struct lcdif_drm_private *lcdif,
 	struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
 	u32 bus_flags = 0;
 
-	if (lcdif->bridge && lcdif->bridge->timings)
+	if (lcdif->bridge->timings)
 		bus_flags = lcdif->bridge->timings->input_bus_flags;
 	else if (bridge_state)
 		bus_flags = bridge_state->input_bus_cfg.flags;
@@ -463,30 +463,21 @@ static void lcdif_crtc_atomic_enable(struct drm_crtc *crtc,
 	struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
 	struct drm_bridge_state *bridge_state = NULL;
 	struct drm_device *drm = lcdif->drm;
-	u32 bus_format = 0;
+	u32 bus_format;
 	dma_addr_t paddr;
 
-	/* If there is a bridge attached to the LCDIF, use its bus format */
-	if (lcdif->bridge) {
-		bridge_state =
-			drm_atomic_get_new_bridge_state(state,
-							lcdif->bridge);
-		if (!bridge_state)
-			bus_format = MEDIA_BUS_FMT_FIXED;
-		else
-			bus_format = bridge_state->input_bus_cfg.format;
-
-		if (bus_format == MEDIA_BUS_FMT_FIXED) {
-			dev_warn_once(drm->dev,
-				      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
-				      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
-			bus_format = MEDIA_BUS_FMT_RGB888_1X24;
-		}
-	}
+	bridge_state = drm_atomic_get_new_bridge_state(state, lcdif->bridge);
+	if (!bridge_state)
+		bus_format = MEDIA_BUS_FMT_FIXED;
+	else
+		bus_format = bridge_state->input_bus_cfg.format;
 
-	/* If all else fails, default to RGB888_1X24 */
-	if (!bus_format)
+	if (bus_format == MEDIA_BUS_FMT_FIXED) {
+		dev_warn_once(drm->dev,
+			      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
+			      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
 		bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+	}
 
 	clk_set_rate(lcdif->clk, m->crtc_clock * 1000);
 
-- 
2.37.1

[PATCH v5 3/6] drm: lcdif: Determine bus format and flags in ->atomic_check()

[Liu Ying]

Instead of determining LCDIF output bus format and bus flags in
->atomic_enable(), do that in ->atomic_check().  This is a
preparation for the upcoming patch to check consistent bus format
and bus flags across all first downstream bridges in ->atomic_check().
New lcdif_crtc_state structure is introduced to cache bus format
and bus flags states in ->atomic_check() so that they can be read
in ->atomic_enable().

Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
v4->v5:
* Add Alexander's R-b and T-b tags.

v3->v4:
* Use 'new_{c,p}state' instead of 'new_{crtc,plane}_state'. (Alexander)
* Simplify lcdif_crtc_reset() by calling lcdif_crtc_atomic_destroy_state().
  (Alexander)
* Add '!crtc->state' check in lcdif_crtc_atomic_duplicate_state(). (Alexander)

v2->v3:
* No change.

v1->v2:
* Split from patch 2/2 in v1. (Marek, Alexander)
* Add comment on the 'base' member of lcdif_crtc_state structure to
  note it should always be the first member. (Lothar)

 drivers/gpu/drm/mxsfb/lcdif_kms.c | 134 ++++++++++++++++++++++--------
 1 file changed, 99 insertions(+), 35 deletions(-)

diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
index e54200a9fcb9..d46de433cd8e 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
@@ -30,6 +30,18 @@
 #include "lcdif_drv.h"
 #include "lcdif_regs.h"
 
+struct lcdif_crtc_state {
+	struct drm_crtc_state	base;	/* always be the first member */
+	u32			bus_format;
+	u32			bus_flags;
+};
+
+static inline struct lcdif_crtc_state *
+to_lcdif_crtc_state(struct drm_crtc_state *s)
+{
+	return container_of(s, struct lcdif_crtc_state, base);
+}
+
 /* -----------------------------------------------------------------------------
  * CRTC
  */
@@ -385,48 +397,72 @@ static void lcdif_reset_block(struct lcdif_drm_private *lcdif)
 	readl(lcdif->base + LCDC_V8_CTRL);
 }
 
-static void lcdif_crtc_mode_set_nofb(struct lcdif_drm_private *lcdif,
-				     struct drm_plane_state *plane_state,
-				     struct drm_bridge_state *bridge_state,
-				     const u32 bus_format)
+static void lcdif_crtc_mode_set_nofb(struct drm_crtc_state *crtc_state,
+				     struct drm_plane_state *plane_state)
 {
-	struct drm_device *drm = lcdif->crtc.dev;
-	struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
-	u32 bus_flags = 0;
-
-	if (lcdif->bridge->timings)
-		bus_flags = lcdif->bridge->timings->input_bus_flags;
-	else if (bridge_state)
-		bus_flags = bridge_state->input_bus_cfg.flags;
+	struct lcdif_crtc_state *lcdif_crtc_state = to_lcdif_crtc_state(crtc_state);
+	struct drm_device *drm = crtc_state->crtc->dev;
+	struct lcdif_drm_private *lcdif = to_lcdif_drm_private(drm);
+	struct drm_display_mode *m = &crtc_state->adjusted_mode;
 
 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Pixel clock: %dkHz (actual: %dkHz)\n",
 			     m->crtc_clock,
 			     (int)(clk_get_rate(lcdif->clk) / 1000));
 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Bridge bus_flags: 0x%08X\n",
-			     bus_flags);
+			     lcdif_crtc_state->bus_flags);
 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Mode flags: 0x%08X\n", m->flags);
 
 	/* Mandatory eLCDIF reset as per the Reference Manual */
 	lcdif_reset_block(lcdif);
 
-	lcdif_set_formats(lcdif, plane_state, bus_format);
+	lcdif_set_formats(lcdif, plane_state, lcdif_crtc_state->bus_format);
 
-	lcdif_set_mode(lcdif, bus_flags);
+	lcdif_set_mode(lcdif, lcdif_crtc_state->bus_flags);
 }
 
 static int lcdif_crtc_atomic_check(struct drm_crtc *crtc,
 				   struct drm_atomic_state *state)
 {
+	struct drm_device *drm = crtc->dev;
+	struct lcdif_drm_private *lcdif = to_lcdif_drm_private(drm);
 	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state,
 									  crtc);
+	struct lcdif_crtc_state *lcdif_crtc_state = to_lcdif_crtc_state(crtc_state);
 	bool has_primary = crtc_state->plane_mask &
 			   drm_plane_mask(crtc->primary);
+	struct drm_bridge_state *bridge_state;
+	struct drm_bridge *bridge = lcdif->bridge;
+	int ret;
 
 	/* The primary plane has to be enabled when the CRTC is active. */
 	if (crtc_state->active && !has_primary)
 		return -EINVAL;
 
-	return drm_atomic_add_affected_planes(state, crtc);
+	ret = drm_atomic_add_affected_planes(state, crtc);
+	if (ret)
+		return ret;
+
+	bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
+	if (!bridge_state)
+		lcdif_crtc_state->bus_format = MEDIA_BUS_FMT_FIXED;
+	else
+		lcdif_crtc_state->bus_format = bridge_state->input_bus_cfg.format;
+
+	if (lcdif_crtc_state->bus_format == MEDIA_BUS_FMT_FIXED) {
+		dev_warn_once(drm->dev,
+			      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
+			      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
+		lcdif_crtc_state->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+	}
+
+	if (bridge->timings)
+		lcdif_crtc_state->bus_flags = bridge->timings->input_bus_flags;
+	else if (bridge_state)
+		lcdif_crtc_state->bus_flags = bridge_state->input_bus_cfg.flags;
+	else
+		lcdif_crtc_state->bus_flags = 0;
+
+	return 0;
 }
 
 static void lcdif_crtc_atomic_flush(struct drm_crtc *crtc,
@@ -458,32 +494,18 @@ static void lcdif_crtc_atomic_enable(struct drm_crtc *crtc,
 				     struct drm_atomic_state *state)
 {
 	struct lcdif_drm_private *lcdif = to_lcdif_drm_private(crtc->dev);
+	struct drm_crtc_state *new_cstate = drm_atomic_get_new_crtc_state(state, crtc);
 	struct drm_plane_state *new_pstate = drm_atomic_get_new_plane_state(state,
 									    crtc->primary);
 	struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
-	struct drm_bridge_state *bridge_state = NULL;
 	struct drm_device *drm = lcdif->drm;
-	u32 bus_format;
 	dma_addr_t paddr;
 
-	bridge_state = drm_atomic_get_new_bridge_state(state, lcdif->bridge);
-	if (!bridge_state)
-		bus_format = MEDIA_BUS_FMT_FIXED;
-	else
-		bus_format = bridge_state->input_bus_cfg.format;
-
-	if (bus_format == MEDIA_BUS_FMT_FIXED) {
-		dev_warn_once(drm->dev,
-			      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
-			      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
-		bus_format = MEDIA_BUS_FMT_RGB888_1X24;
-	}
-
 	clk_set_rate(lcdif->clk, m->crtc_clock * 1000);
 
 	pm_runtime_get_sync(drm->dev);
 
-	lcdif_crtc_mode_set_nofb(lcdif, new_pstate, bridge_state, bus_format);
+	lcdif_crtc_mode_set_nofb(new_cstate, new_pstate);
 
 	/* Write cur_buf as well to avoid an initial corrupt frame */
 	paddr = drm_fb_dma_get_gem_addr(new_pstate->fb, new_pstate, 0);
@@ -520,6 +542,48 @@ static void lcdif_crtc_atomic_disable(struct drm_crtc *crtc,
 	pm_runtime_put_sync(drm->dev);
 }
 
+static void lcdif_crtc_atomic_destroy_state(struct drm_crtc *crtc,
+					    struct drm_crtc_state *state)
+{
+	__drm_atomic_helper_crtc_destroy_state(state);
+	kfree(to_lcdif_crtc_state(state));
+}
+
+static void lcdif_crtc_reset(struct drm_crtc *crtc)
+{
+	struct lcdif_crtc_state *state;
+
+	if (crtc->state)
+		lcdif_crtc_atomic_destroy_state(crtc, crtc->state);
+
+	crtc->state = NULL;
+
+	state = kzalloc(sizeof(*state), GFP_KERNEL);
+	if (state)
+		__drm_atomic_helper_crtc_reset(crtc, &state->base);
+}
+
+static struct drm_crtc_state *
+lcdif_crtc_atomic_duplicate_state(struct drm_crtc *crtc)
+{
+	struct lcdif_crtc_state *old = to_lcdif_crtc_state(crtc->state);
+	struct lcdif_crtc_state *new;
+
+	if (WARN_ON(!crtc->state))
+		return NULL;
+
+	new = kzalloc(sizeof(*new), GFP_KERNEL);
+	if (!new)
+		return NULL;
+
+	__drm_atomic_helper_crtc_duplicate_state(crtc, &new->base);
+
+	new->bus_format = old->bus_format;
+	new->bus_flags = old->bus_flags;
+
+	return &new->base;
+}
+
 static int lcdif_crtc_enable_vblank(struct drm_crtc *crtc)
 {
 	struct lcdif_drm_private *lcdif = to_lcdif_drm_private(crtc->dev);
@@ -548,12 +612,12 @@ static const struct drm_crtc_helper_funcs lcdif_crtc_helper_funcs = {
 };
 
 static const struct drm_crtc_funcs lcdif_crtc_funcs = {
-	.reset = drm_atomic_helper_crtc_reset,
+	.reset = lcdif_crtc_reset,
 	.destroy = drm_crtc_cleanup,
 	.set_config = drm_atomic_helper_set_config,
 	.page_flip = drm_atomic_helper_page_flip,
-	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
-	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
+	.atomic_duplicate_state = lcdif_crtc_atomic_duplicate_state,
+	.atomic_destroy_state = lcdif_crtc_atomic_destroy_state,
 	.enable_vblank = lcdif_crtc_enable_vblank,
 	.disable_vblank = lcdif_crtc_disable_vblank,
 };
-- 
2.37.1

[PATCH v5 4/6] drm: lcdif: Check consistent bus format and flags across first bridges

[Liu Ying]

The single LCDIF embedded in i.MX93 SoC may drive multiple displays
simultaneously.  Check bus format and flags across first bridges in
->atomic_check() to ensure they are consistent.  This is a preparation
for adding i.MX93 LCDIF support.

Acked-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
v4->v5:
* Add Alexander's A-b and T-b tags.

v3->v4:
* No change.

v2->v3:
* No change.

v1->v2:
* Split from patch 2/2 in v1. (Marek, Alexander)
* Drop a comment about bridge input bus format from lcdif_crtc_atomic_check().

 drivers/gpu/drm/mxsfb/lcdif_drv.c |  2 -
 drivers/gpu/drm/mxsfb/lcdif_drv.h |  1 -
 drivers/gpu/drm/mxsfb/lcdif_kms.c | 76 ++++++++++++++++++++++---------
 3 files changed, 55 insertions(+), 24 deletions(-)

diff --git a/drivers/gpu/drm/mxsfb/lcdif_drv.c b/drivers/gpu/drm/mxsfb/lcdif_drv.c
index 6fb5b469ee5a..e816f87828fb 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_drv.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_drv.c
@@ -52,8 +52,6 @@ static int lcdif_attach_bridge(struct lcdif_drm_private *lcdif)
 	if (ret)
 		return dev_err_probe(drm->dev, ret, "Failed to attach bridge\n");
 
-	lcdif->bridge = bridge;
-
 	return 0;
 }
 
diff --git a/drivers/gpu/drm/mxsfb/lcdif_drv.h b/drivers/gpu/drm/mxsfb/lcdif_drv.h
index 6cdba6e20c02..aa6d099a1897 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_drv.h
+++ b/drivers/gpu/drm/mxsfb/lcdif_drv.h
@@ -31,7 +31,6 @@ struct lcdif_drm_private {
 	} planes;
 	struct drm_crtc			crtc;
 	struct drm_encoder		encoder;
-	struct drm_bridge		*bridge;
 };
 
 static inline struct lcdif_drm_private *
diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
index d46de433cd8e..d6009b353a16 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
@@ -17,6 +17,7 @@
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_bridge.h>
 #include <drm/drm_color_mgmt.h>
+#include <drm/drm_connector.h>
 #include <drm/drm_crtc.h>
 #include <drm/drm_encoder.h>
 #include <drm/drm_fb_dma_helper.h>
@@ -424,15 +425,19 @@ static int lcdif_crtc_atomic_check(struct drm_crtc *crtc,
 				   struct drm_atomic_state *state)
 {
 	struct drm_device *drm = crtc->dev;
-	struct lcdif_drm_private *lcdif = to_lcdif_drm_private(drm);
 	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state,
 									  crtc);
 	struct lcdif_crtc_state *lcdif_crtc_state = to_lcdif_crtc_state(crtc_state);
 	bool has_primary = crtc_state->plane_mask &
 			   drm_plane_mask(crtc->primary);
+	struct drm_connector_state *connector_state;
+	struct drm_connector *connector;
+	struct drm_encoder *encoder;
 	struct drm_bridge_state *bridge_state;
-	struct drm_bridge *bridge = lcdif->bridge;
-	int ret;
+	struct drm_bridge *bridge;
+	u32 bus_format, bus_flags;
+	bool format_set = false, flags_set = false;
+	int ret, i;
 
 	/* The primary plane has to be enabled when the CRTC is active. */
 	if (crtc_state->active && !has_primary)
@@ -442,26 +447,55 @@ static int lcdif_crtc_atomic_check(struct drm_crtc *crtc,
 	if (ret)
 		return ret;
 
-	bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
-	if (!bridge_state)
-		lcdif_crtc_state->bus_format = MEDIA_BUS_FMT_FIXED;
-	else
-		lcdif_crtc_state->bus_format = bridge_state->input_bus_cfg.format;
-
-	if (lcdif_crtc_state->bus_format == MEDIA_BUS_FMT_FIXED) {
-		dev_warn_once(drm->dev,
-			      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
-			      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
-		lcdif_crtc_state->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+	/* Try to find consistent bus format and flags across first bridges. */
+	for_each_new_connector_in_state(state, connector, connector_state, i) {
+		if (!connector_state->crtc)
+			continue;
+
+		encoder = connector_state->best_encoder;
+
+		bridge = drm_bridge_chain_get_first_bridge(encoder);
+		if (!bridge)
+			continue;
+
+		bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
+		if (!bridge_state)
+			bus_format = MEDIA_BUS_FMT_FIXED;
+		else
+			bus_format = bridge_state->input_bus_cfg.format;
+
+		if (bus_format == MEDIA_BUS_FMT_FIXED) {
+			dev_warn(drm->dev,
+				 "[ENCODER:%d:%s]'s bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
+				 "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n",
+				 encoder->base.id, encoder->name);
+			bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+		}
+
+		if (!format_set) {
+			lcdif_crtc_state->bus_format = bus_format;
+			format_set = true;
+		} else if (lcdif_crtc_state->bus_format != bus_format) {
+			DRM_DEV_DEBUG_DRIVER(drm->dev, "inconsistent bus format\n");
+			return -EINVAL;
+		}
+
+		if (bridge->timings)
+			bus_flags = bridge->timings->input_bus_flags;
+		else if (bridge_state)
+			bus_flags = bridge_state->input_bus_cfg.flags;
+		else
+			bus_flags = 0;
+
+		if (!flags_set) {
+			lcdif_crtc_state->bus_flags = bus_flags;
+			flags_set = true;
+		} else if (lcdif_crtc_state->bus_flags != bus_flags) {
+			DRM_DEV_DEBUG_DRIVER(drm->dev, "inconsistent bus flags\n");
+			return -EINVAL;
+		}
 	}
 
-	if (bridge->timings)
-		lcdif_crtc_state->bus_flags = bridge->timings->input_bus_flags;
-	else if (bridge_state)
-		lcdif_crtc_state->bus_flags = bridge_state->input_bus_cfg.flags;
-	else
-		lcdif_crtc_state->bus_flags = 0;
-
 	return 0;
 }
 
-- 
2.37.1

[PATCH v5 5/6] drm: lcdif: Add multiple encoders and first bridges support

[Liu Ying]

The single LCDIF embedded in i.MX93 SoC may drive multiple displays
simultaneously.  Look at LCDIF output port's remote port parents to
find all enabled first bridges.  Add an encoder for each found bridge
and attach the bridge to the encoder.  This is a preparation for
adding i.MX93 LCDIF support.

Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Acked-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
v4->v5:
* Rebase upon v6.4-rc1 and resolve a trivial conflict.
* Add Alexander's A-b and T-b tags.

v3->v4:
* Improve warning message when ignoring invalid LCDIF OF endpoint ids.
  (Alexander)

v2->v3:
* No change.

v1->v2:
* Split from patch 2/2 in v1. (Marek, Alexander)
* Drop '!remote ||' from lcdif_attach_bridge(). (Lothar)
* Drop unneeded 'bridges' member from lcdif_drm_private structure.

 drivers/gpu/drm/mxsfb/lcdif_drv.c | 68 +++++++++++++++++++++++++++----
 drivers/gpu/drm/mxsfb/lcdif_drv.h |  4 +-
 drivers/gpu/drm/mxsfb/lcdif_kms.c | 21 ++--------
 3 files changed, 66 insertions(+), 27 deletions(-)

diff --git a/drivers/gpu/drm/mxsfb/lcdif_drv.c b/drivers/gpu/drm/mxsfb/lcdif_drv.c
index e816f87828fb..cf27b63b1899 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_drv.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_drv.c
@@ -9,13 +9,16 @@
 #include <linux/dma-mapping.h>
 #include <linux/io.h>
 #include <linux/module.h>
+#include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/of_graph.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_bridge.h>
 #include <drm/drm_drv.h>
+#include <drm/drm_encoder.h>
 #include <drm/drm_fbdev_dma.h>
 #include <drm/drm_gem_dma_helper.h>
 #include <drm/drm_gem_framebuffer_helper.h>
@@ -38,19 +41,68 @@ static const struct drm_mode_config_helper_funcs lcdif_mode_config_helpers = {
 	.atomic_commit_tail = drm_atomic_helper_commit_tail_rpm,
 };
 
+static const struct drm_encoder_funcs lcdif_encoder_funcs = {
+	.destroy = drm_encoder_cleanup,
+};
+
 static int lcdif_attach_bridge(struct lcdif_drm_private *lcdif)
 {
-	struct drm_device *drm = lcdif->drm;
+	struct device *dev = lcdif->drm->dev;
+	struct device_node *ep;
 	struct drm_bridge *bridge;
 	int ret;
 
-	bridge = devm_drm_of_get_bridge(drm->dev, drm->dev->of_node, 0, 0);
-	if (IS_ERR(bridge))
-		return PTR_ERR(bridge);
-
-	ret = drm_bridge_attach(&lcdif->encoder, bridge, NULL, 0);
-	if (ret)
-		return dev_err_probe(drm->dev, ret, "Failed to attach bridge\n");
+	for_each_endpoint_of_node(dev->of_node, ep) {
+		struct device_node *remote;
+		struct of_endpoint of_ep;
+		struct drm_encoder *encoder;
+
+		remote = of_graph_get_remote_port_parent(ep);
+		if (!of_device_is_available(remote)) {
+			of_node_put(remote);
+			continue;
+		}
+		of_node_put(remote);
+
+		ret = of_graph_parse_endpoint(ep, &of_ep);
+		if (ret < 0) {
+			dev_err(dev, "Failed to parse endpoint %pOF\n", ep);
+			of_node_put(ep);
+			return ret;
+		}
+
+		if (of_ep.id >= MAX_DISPLAYS) {
+			dev_warn(dev, "ingoring invalid endpoint id %u\n", of_ep.id);
+			continue;
+		}
+
+		bridge = devm_drm_of_get_bridge(dev, dev->of_node, 0, of_ep.id);
+		if (IS_ERR(bridge)) {
+			of_node_put(ep);
+			return dev_err_probe(dev, PTR_ERR(bridge),
+					     "Failed to get bridge for endpoint%u\n",
+					     of_ep.id);
+		}
+
+		encoder = &lcdif->encoders[of_ep.id];
+		encoder->possible_crtcs = drm_crtc_mask(&lcdif->crtc);
+		ret = drm_encoder_init(lcdif->drm, encoder, &lcdif_encoder_funcs,
+				       DRM_MODE_ENCODER_NONE, NULL);
+		if (ret) {
+			dev_err(dev, "Failed to initialize encoder for endpoint%u: %d\n",
+				of_ep.id, ret);
+			of_node_put(ep);
+			return ret;
+		}
+
+		ret = drm_bridge_attach(encoder, bridge, NULL, 0);
+		if (ret) {
+			of_node_put(ep);
+			return dev_err_probe(dev, ret,
+					     "Failed to attach bridge for endpoint%u\n",
+					     of_ep.id);
+		}
+	}
 
 	return 0;
 }
diff --git a/drivers/gpu/drm/mxsfb/lcdif_drv.h b/drivers/gpu/drm/mxsfb/lcdif_drv.h
index aa6d099a1897..c7400bd9bbd9 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_drv.h
+++ b/drivers/gpu/drm/mxsfb/lcdif_drv.h
@@ -14,6 +14,8 @@
 #include <drm/drm_encoder.h>
 #include <drm/drm_plane.h>
 
+#define MAX_DISPLAYS	3
+
 struct clk;
 
 struct lcdif_drm_private {
@@ -30,7 +32,7 @@ struct lcdif_drm_private {
 		/* i.MXRT does support overlay planes, add them here. */
 	} planes;
 	struct drm_crtc			crtc;
-	struct drm_encoder		encoder;
+	struct drm_encoder		encoders[MAX_DISPLAYS];
 };
 
 static inline struct lcdif_drm_private *
diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
index d6009b353a16..c35d769f91dd 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
@@ -656,14 +656,6 @@ static const struct drm_crtc_funcs lcdif_crtc_funcs = {
 	.disable_vblank = lcdif_crtc_disable_vblank,
 };
 
-/* -----------------------------------------------------------------------------
- * Encoder
- */
-
-static const struct drm_encoder_funcs lcdif_encoder_funcs = {
-	.destroy = drm_encoder_cleanup,
-};
-
 /* -----------------------------------------------------------------------------
  * Planes
  */
@@ -756,7 +748,6 @@ int lcdif_kms_init(struct lcdif_drm_private *lcdif)
 					BIT(DRM_COLOR_YCBCR_BT2020);
 	const u32 supported_ranges = BIT(DRM_COLOR_YCBCR_LIMITED_RANGE) |
 				     BIT(DRM_COLOR_YCBCR_FULL_RANGE);
-	struct drm_encoder *encoder = &lcdif->encoder;
 	struct drm_crtc *crtc = &lcdif->crtc;
 	int ret;
 
@@ -780,13 +771,7 @@ int lcdif_kms_init(struct lcdif_drm_private *lcdif)
 		return ret;
 
 	drm_crtc_helper_add(crtc, &lcdif_crtc_helper_funcs);
-	ret = drm_crtc_init_with_planes(lcdif->drm, crtc,
-					&lcdif->planes.primary, NULL,
-					&lcdif_crtc_funcs, NULL);
-	if (ret)
-		return ret;
-
-	encoder->possible_crtcs = drm_crtc_mask(crtc);
-	return drm_encoder_init(lcdif->drm, encoder, &lcdif_encoder_funcs,
-				DRM_MODE_ENCODER_NONE, NULL);
+	return drm_crtc_init_with_planes(lcdif->drm, crtc,
+					 &lcdif->planes.primary, NULL,
+					 &lcdif_crtc_funcs, NULL);
 }
-- 
2.37.1

[PATCH v5 6/6] drm: lcdif: Add i.MX93 LCDIF compatible string

[Liu Ying]

With all previous preparations done to make it possible for the
single LCDIF embedded in i.MX93 SoC to drive multiple displays
simultaneously, add i.MX93 LCDIF compatible string as the last
step of adding i.MX93 LCDIF support.

Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
v4->v5:
* Add Alexander's T-b tag.

v3->v4:
* Add Alexander's R-b tag.

v2->v3:
* Fix a trivial typo in commit message.

v1->v2:
* Split from patch 2/2 in v1. (Marek, Alexander)

 drivers/gpu/drm/mxsfb/lcdif_drv.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/mxsfb/lcdif_drv.c b/drivers/gpu/drm/mxsfb/lcdif_drv.c
index cf27b63b1899..d1bd0f51f451 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_drv.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_drv.c
@@ -249,6 +249,7 @@ static const struct drm_driver lcdif_driver = {
 
 static const struct of_device_id lcdif_dt_ids[] = {
 	{ .compatible = "fsl,imx8mp-lcdif" },
+	{ .compatible = "fsl,imx93-lcdif" },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, lcdif_dt_ids);
-- 
2.37.1

Re: [PATCH v5 1/6] dt-bindings: lcdif: Add i.MX93 LCDIF support

[Rob Herring]

On Mon, 08 May 2023 13:57:35 +0800, Liu Ying wrote:
> There is one LCDIF embedded in i.MX93 SoC to connect with
> MIPI DSI controller through LCDIF cross line pattern(controlled
> by mediamix blk-ctrl) or connect with LVDS display bridge(LDB)
> directly or connect with a parallel display through parallel
> display format(also controlled by mediamix blk-ctrl).  i.MX93
> LCDIF IP is essentially the same to i.MX8MP LCDIF IP.  Add device
> tree binding for i.MX93 LCDIF.
> 
> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> Reviewed-by: Marek Vasut <marex@denx.de>
> Reviewed-by: Alexander Stein <alexander.stein@ew.tq-group.com>
> Signed-off-by: Liu Ying <victor.liu@nxp.com>
> ---
> v4->v5:
> * No change.
> 
> v3->v4:
> * Add Alexander's R-b tag.
> 
> v2->v3:
> * No change.
> 
> v1->v2:
> * Add Krzysztof's A-b and Marek's R-b tags.
> 
>  Documentation/devicetree/bindings/display/fsl,lcdif.yaml | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/media/i2c/ovti,ov2685.example.dtb: camera-sensor@3c: port:endpoint:data-lanes: [[1]] is too short
	From schema: /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/media/i2c/ovti,ov2685.yaml
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/media/rockchip-isp1.example.dtb: camera@3c: port:endpoint:data-lanes: [[1]] is too short
	From schema: /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/media/i2c/ovti,ov2685.yaml
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie-ep.example.dtb: pcie-ep@33800000: Unevaluated properties are not allowed ('assigned-clock-parents', 'assigned-clock-rates', 'assigned-clocks' were unexpected)
	From schema: /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie-ep.yaml

doc reference errors (make refcheckdocs):
Documentation/usb/gadget_uvc.rst: Documentation/userspace-api/media/v4l/pixfmt-packed.yuv.rst
MAINTAINERS: Documentation/devicetree/bindings/pwm/pwm-apple.yaml

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20230508055740.635256-2-victor.liu@nxp.com

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.

Re: [PATCH v5 2/6] drm: lcdif: Drop unnecessary NULL pointer check on lcdif->bridge

[Marek Vasut]

On 5/8/23 07:57, Liu Ying wrote:

Hi,

> diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
> index 262bc43b1079..e54200a9fcb9 100644
> --- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
> +++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
> @@ -394,7 +394,7 @@ static void lcdif_crtc_mode_set_nofb(struct lcdif_drm_private *lcdif,
>   	struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
>   	u32 bus_flags = 0;
>   
> -	if (lcdif->bridge && lcdif->bridge->timings)
> +	if (lcdif->bridge->timings)
>   		bus_flags = lcdif->bridge->timings->input_bus_flags;
>   	else if (bridge_state)
>   		bus_flags = bridge_state->input_bus_cfg.flags;
> @@ -463,30 +463,21 @@ static void lcdif_crtc_atomic_enable(struct drm_crtc *crtc,
>   	struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
>   	struct drm_bridge_state *bridge_state = NULL;
>   	struct drm_device *drm = lcdif->drm;
> -	u32 bus_format = 0;
> +	u32 bus_format;
>   	dma_addr_t paddr;
>   
> -	/* If there is a bridge attached to the LCDIF, use its bus format */
> -	if (lcdif->bridge) {
> -		bridge_state =
> -			drm_atomic_get_new_bridge_state(state,
> -							lcdif->bridge);
> -		if (!bridge_state)
> -			bus_format = MEDIA_BUS_FMT_FIXED;
> -		else
> -			bus_format = bridge_state->input_bus_cfg.format;
> -
> -		if (bus_format == MEDIA_BUS_FMT_FIXED) {
> -			dev_warn_once(drm->dev,
> -				      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
> -				      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
> -			bus_format = MEDIA_BUS_FMT_RGB888_1X24;
> -		}
> -	}
> +	bridge_state = drm_atomic_get_new_bridge_state(state, lcdif->bridge);
> +	if (!bridge_state)
> +		bus_format = MEDIA_BUS_FMT_FIXED;
> +	else
> +		bus_format = bridge_state->input_bus_cfg.format;

The code below seems to change the logic slightly.

Could it happen that:
- bridge_state is valid (i.e. non-NULL)
- bridge_state->input_bus_cfg.format is set to 0 (i.e. not set) ?
   (note that MEDIA_BUS_FMT_FIXED is defined as 0x0001)

> -	/* If all else fails, default to RGB888_1X24 */
> -	if (!bus_format)
> +	if (bus_format == MEDIA_BUS_FMT_FIXED) {
> +		dev_warn_once(drm->dev,
> +			      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
> +			      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
>   		bus_format = MEDIA_BUS_FMT_RGB888_1X24;
> +	}
>   
>   	clk_set_rate(lcdif->clk, m->crtc_clock * 1000);

[...]

Re: [PATCH v5 3/6] drm: lcdif: Determine bus format and flags in ->atomic_check()

[Marek Vasut]

On 5/8/23 07:57, Liu Ying wrote:
> Instead of determining LCDIF output bus format and bus flags in
> ->atomic_enable(), do that in ->atomic_check().  This is a
> preparation for the upcoming patch to check consistent bus format
> and bus flags across all first downstream bridges in ->atomic_check().
> New lcdif_crtc_state structure is introduced to cache bus format
> and bus flags states in ->atomic_check() so that they can be read
> in ->atomic_enable().
> 
> Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
> Reviewed-by: Alexander Stein <alexander.stein@ew.tq-group.com>
> Signed-off-by: Liu Ying <victor.liu@nxp.com>

Reviewed-by: Marek Vasut <marex@denx.de>

Re: [PATCH v5 4/6] drm: lcdif: Check consistent bus format and flags across first bridges

[Marek Vasut]

On 5/8/23 07:57, Liu Ying wrote:
> The single LCDIF embedded in i.MX93 SoC may drive multiple displays
> simultaneously.  Check bus format and flags across first bridges in
> ->atomic_check() to ensure they are consistent.  This is a preparation
> for adding i.MX93 LCDIF support.
> 
> Acked-by: Alexander Stein <alexander.stein@ew.tq-group.com>
> Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
> Signed-off-by: Liu Ying <victor.liu@nxp.com>

Reviewed-by: Marek Vasut <marex@denx.de>

Re: [PATCH v5 5/6] drm: lcdif: Add multiple encoders and first bridges support

[Marek Vasut]

On 5/8/23 07:57, Liu Ying wrote:
> The single LCDIF embedded in i.MX93 SoC may drive multiple displays
> simultaneously.  Look at LCDIF output port's remote port parents to
> find all enabled first bridges.  Add an encoder for each found bridge
> and attach the bridge to the encoder.  This is a preparation for
> adding i.MX93 LCDIF support.
> 
> Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
> Acked-by: Alexander Stein <alexander.stein@ew.tq-group.com>
> Signed-off-by: Liu Ying <victor.liu@nxp.com>
> ---
> v4->v5:
> * Rebase upon v6.4-rc1 and resolve a trivial conflict.
> * Add Alexander's A-b and T-b tags.
> 
> v3->v4:
> * Improve warning message when ignoring invalid LCDIF OF endpoint ids.
>    (Alexander)
> 
> v2->v3:
> * No change.
> 
> v1->v2:
> * Split from patch 2/2 in v1. (Marek, Alexander)
> * Drop '!remote ||' from lcdif_attach_bridge(). (Lothar)
> * Drop unneeded 'bridges' member from lcdif_drm_private structure.
> 
>   drivers/gpu/drm/mxsfb/lcdif_drv.c | 68 +++++++++++++++++++++++++++----
>   drivers/gpu/drm/mxsfb/lcdif_drv.h |  4 +-
>   drivers/gpu/drm/mxsfb/lcdif_kms.c | 21 ++--------
>   3 files changed, 66 insertions(+), 27 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mxsfb/lcdif_drv.c b/drivers/gpu/drm/mxsfb/lcdif_drv.c
> index e816f87828fb..cf27b63b1899 100644
> --- a/drivers/gpu/drm/mxsfb/lcdif_drv.c
> +++ b/drivers/gpu/drm/mxsfb/lcdif_drv.c
> @@ -9,13 +9,16 @@
>   #include <linux/dma-mapping.h>
>   #include <linux/io.h>
>   #include <linux/module.h>
> +#include <linux/of.h>
>   #include <linux/of_device.h>
> +#include <linux/of_graph.h>
>   #include <linux/platform_device.h>
>   #include <linux/pm_runtime.h>
>   
>   #include <drm/drm_atomic_helper.h>
>   #include <drm/drm_bridge.h>
>   #include <drm/drm_drv.h>
> +#include <drm/drm_encoder.h>
>   #include <drm/drm_fbdev_dma.h>
>   #include <drm/drm_gem_dma_helper.h>
>   #include <drm/drm_gem_framebuffer_helper.h>
> @@ -38,19 +41,68 @@ static const struct drm_mode_config_helper_funcs lcdif_mode_config_helpers = {
>   	.atomic_commit_tail = drm_atomic_helper_commit_tail_rpm,
>   };
>   
> +static const struct drm_encoder_funcs lcdif_encoder_funcs = {
> +	.destroy = drm_encoder_cleanup,
> +};
> +
>   static int lcdif_attach_bridge(struct lcdif_drm_private *lcdif)
>   {
> -	struct drm_device *drm = lcdif->drm;
> +	struct device *dev = lcdif->drm->dev;
> +	struct device_node *ep;
>   	struct drm_bridge *bridge;
>   	int ret;
>   
> -	bridge = devm_drm_of_get_bridge(drm->dev, drm->dev->of_node, 0, 0);
> -	if (IS_ERR(bridge))
> -		return PTR_ERR(bridge);
> -
> -	ret = drm_bridge_attach(&lcdif->encoder, bridge, NULL, 0);
> -	if (ret)
> -		return dev_err_probe(drm->dev, ret, "Failed to attach bridge\n");
> +	for_each_endpoint_of_node(dev->of_node, ep) {
> +		struct device_node *remote;
> +		struct of_endpoint of_ep;
> +		struct drm_encoder *encoder;
> +
> +		remote = of_graph_get_remote_port_parent(ep);
> +		if (!of_device_is_available(remote)) {
> +			of_node_put(remote);
> +			continue;
> +		}
> +		of_node_put(remote);
> +
> +		ret = of_graph_parse_endpoint(ep, &of_ep);
> +		if (ret < 0) {
> +			dev_err(dev, "Failed to parse endpoint %pOF\n", ep);
> +			of_node_put(ep);
> +			return ret;
> +		}
> +
> +		if (of_ep.id >= MAX_DISPLAYS) {

Can we make the maximum number of displays, or really bridge, specific 
to IP instance instead (1 for mx8mp, 3 for mx93) ? If so, then I think 
we need to track a list of bridges in some linked list or some such 
dynamic structure, which would allow us to get rid of MAX_DISPLAYS macro.

> +			dev_warn(dev, "ingoring invalid endpoint id %u\n", of_ep.id);

s@ingoring@ignoring@

[...]

Re: [PATCH v5 6/6] drm: lcdif: Add i.MX93 LCDIF compatible string

[Marek Vasut]

On 5/8/23 07:57, Liu Ying wrote:
> With all previous preparations done to make it possible for the
> single LCDIF embedded in i.MX93 SoC to drive multiple displays
> simultaneously, add i.MX93 LCDIF compatible string as the last
> step of adding i.MX93 LCDIF support.
> 
> Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
> Reviewed-by: Alexander Stein <alexander.stein@ew.tq-group.com>
> Signed-off-by: Liu Ying <victor.liu@nxp.com>

Reviewed-by: Marek Vasut <marex@denx.de>

Re: [PATCH v5 2/6] drm: lcdif: Drop unnecessary NULL pointer check on lcdif->bridge

[Ying Liu]

On Tue, May 9, 2023 at 10:14 AM Marek Vasut <marex@denx.de> wrote:
>
> On 5/8/23 07:57, Liu Ying wrote:
>
> Hi,

Hi,

>
> > diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
> > index 262bc43b1079..e54200a9fcb9 100644
> > --- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
> > +++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
> > @@ -394,7 +394,7 @@ static void lcdif_crtc_mode_set_nofb(struct lcdif_drm_private *lcdif,
> >       struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
> >       u32 bus_flags = 0;
> >
> > -     if (lcdif->bridge && lcdif->bridge->timings)
> > +     if (lcdif->bridge->timings)
> >               bus_flags = lcdif->bridge->timings->input_bus_flags;
> >       else if (bridge_state)
> >               bus_flags = bridge_state->input_bus_cfg.flags;
> > @@ -463,30 +463,21 @@ static void lcdif_crtc_atomic_enable(struct drm_crtc *crtc,
> >       struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
> >       struct drm_bridge_state *bridge_state = NULL;
> >       struct drm_device *drm = lcdif->drm;
> > -     u32 bus_format = 0;
> > +     u32 bus_format;
> >       dma_addr_t paddr;
> >
> > -     /* If there is a bridge attached to the LCDIF, use its bus format */
> > -     if (lcdif->bridge) {
> > -             bridge_state =
> > -                     drm_atomic_get_new_bridge_state(state,
> > -                                                     lcdif->bridge);
> > -             if (!bridge_state)
> > -                     bus_format = MEDIA_BUS_FMT_FIXED;
> > -             else
> > -                     bus_format = bridge_state->input_bus_cfg.format;
> > -
> > -             if (bus_format == MEDIA_BUS_FMT_FIXED) {
> > -                     dev_warn_once(drm->dev,
> > -                                   "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
> > -                                   "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
> > -                     bus_format = MEDIA_BUS_FMT_RGB888_1X24;
> > -             }
> > -     }
> > +     bridge_state = drm_atomic_get_new_bridge_state(state, lcdif->bridge);
> > +     if (!bridge_state)
> > +             bus_format = MEDIA_BUS_FMT_FIXED;
> > +     else
> > +             bus_format = bridge_state->input_bus_cfg.format;
>
> The code below seems to change the logic slightly.
>
> Could it happen that:
> - bridge_state is valid (i.e. non-NULL)
> - bridge_state->input_bus_cfg.format is set to 0 (i.e. not set) ?
>    (note that MEDIA_BUS_FMT_FIXED is defined as 0x0001)

Yes, bridge_state->input_bus_cfg.format could be zero.
Will keep the below default MEDIA_BUS_FMT_RGB888_1X24
bus format setting in next version.

Regards,
Liu Ying

>
> > -     /* If all else fails, default to RGB888_1X24 */
> > -     if (!bus_format)
> > +     if (bus_format == MEDIA_BUS_FMT_FIXED) {
> > +             dev_warn_once(drm->dev,
> > +                           "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
> > +                           "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
> >               bus_format = MEDIA_BUS_FMT_RGB888_1X24;
> > +     }
> >
> >       clk_set_rate(lcdif->clk, m->crtc_clock * 1000);
>
> [...]

Re: [PATCH v5 2/6] drm: lcdif: Drop unnecessary NULL pointer check on lcdif->bridge

[Marek Vasut]

On 5/10/23 10:30, Ying Liu wrote:
> On Tue, May 9, 2023 at 10:14 AM Marek Vasut <marex@denx.de> wrote:
>>
>> On 5/8/23 07:57, Liu Ying wrote:
>>
>> Hi,
> 
> Hi,

Hi,

>>> diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
>>> index 262bc43b1079..e54200a9fcb9 100644
>>> --- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
>>> +++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
>>> @@ -394,7 +394,7 @@ static void lcdif_crtc_mode_set_nofb(struct lcdif_drm_private *lcdif,
>>>        struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
>>>        u32 bus_flags = 0;
>>>
>>> -     if (lcdif->bridge && lcdif->bridge->timings)
>>> +     if (lcdif->bridge->timings)
>>>                bus_flags = lcdif->bridge->timings->input_bus_flags;
>>>        else if (bridge_state)
>>>                bus_flags = bridge_state->input_bus_cfg.flags;
>>> @@ -463,30 +463,21 @@ static void lcdif_crtc_atomic_enable(struct drm_crtc *crtc,
>>>        struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
>>>        struct drm_bridge_state *bridge_state = NULL;
>>>        struct drm_device *drm = lcdif->drm;
>>> -     u32 bus_format = 0;
>>> +     u32 bus_format;
>>>        dma_addr_t paddr;
>>>
>>> -     /* If there is a bridge attached to the LCDIF, use its bus format */
>>> -     if (lcdif->bridge) {
>>> -             bridge_state =
>>> -                     drm_atomic_get_new_bridge_state(state,
>>> -                                                     lcdif->bridge);
>>> -             if (!bridge_state)
>>> -                     bus_format = MEDIA_BUS_FMT_FIXED;
>>> -             else
>>> -                     bus_format = bridge_state->input_bus_cfg.format;
>>> -
>>> -             if (bus_format == MEDIA_BUS_FMT_FIXED) {
>>> -                     dev_warn_once(drm->dev,
>>> -                                   "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
>>> -                                   "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
>>> -                     bus_format = MEDIA_BUS_FMT_RGB888_1X24;
>>> -             }
>>> -     }
>>> +     bridge_state = drm_atomic_get_new_bridge_state(state, lcdif->bridge);
>>> +     if (!bridge_state)
>>> +             bus_format = MEDIA_BUS_FMT_FIXED;
>>> +     else
>>> +             bus_format = bridge_state->input_bus_cfg.format;
>>
>> The code below seems to change the logic slightly.
>>
>> Could it happen that:
>> - bridge_state is valid (i.e. non-NULL)
>> - bridge_state->input_bus_cfg.format is set to 0 (i.e. not set) ?
>>     (note that MEDIA_BUS_FMT_FIXED is defined as 0x0001)
> 
> Yes, bridge_state->input_bus_cfg.format could be zero.
> Will keep the below default MEDIA_BUS_FMT_RGB888_1X24
> bus format setting in next version.

Thanks for confirming.

The rest of the series looks good, sorry for the delay in reviews.

Re: [PATCH v5 5/6] drm: lcdif: Add multiple encoders and first bridges support

[Ying Liu]

On Tue, May 9, 2023 at 10:14 AM Marek Vasut <marex@denx.de> wrote:
>
> On 5/8/23 07:57, Liu Ying wrote:
> > The single LCDIF embedded in i.MX93 SoC may drive multiple displays
> > simultaneously.  Look at LCDIF output port's remote port parents to
> > find all enabled first bridges.  Add an encoder for each found bridge
> > and attach the bridge to the encoder.  This is a preparation for
> > adding i.MX93 LCDIF support.
> >
> > Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
> > Acked-by: Alexander Stein <alexander.stein@ew.tq-group.com>
> > Signed-off-by: Liu Ying <victor.liu@nxp.com>
> > ---
> > v4->v5:
> > * Rebase upon v6.4-rc1 and resolve a trivial conflict.
> > * Add Alexander's A-b and T-b tags.
> >
> > v3->v4:
> > * Improve warning message when ignoring invalid LCDIF OF endpoint ids.
> >    (Alexander)
> >
> > v2->v3:
> > * No change.
> >
> > v1->v2:
> > * Split from patch 2/2 in v1. (Marek, Alexander)
> > * Drop '!remote ||' from lcdif_attach_bridge(). (Lothar)
> > * Drop unneeded 'bridges' member from lcdif_drm_private structure.
> >
> >   drivers/gpu/drm/mxsfb/lcdif_drv.c | 68 +++++++++++++++++++++++++++----
> >   drivers/gpu/drm/mxsfb/lcdif_drv.h |  4 +-
> >   drivers/gpu/drm/mxsfb/lcdif_kms.c | 21 ++--------
> >   3 files changed, 66 insertions(+), 27 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/mxsfb/lcdif_drv.c b/drivers/gpu/drm/mxsfb/lcdif_drv.c
> > index e816f87828fb..cf27b63b1899 100644
> > --- a/drivers/gpu/drm/mxsfb/lcdif_drv.c
> > +++ b/drivers/gpu/drm/mxsfb/lcdif_drv.c
> > @@ -9,13 +9,16 @@
> >   #include <linux/dma-mapping.h>
> >   #include <linux/io.h>
> >   #include <linux/module.h>
> > +#include <linux/of.h>
> >   #include <linux/of_device.h>
> > +#include <linux/of_graph.h>
> >   #include <linux/platform_device.h>
> >   #include <linux/pm_runtime.h>
> >
> >   #include <drm/drm_atomic_helper.h>
> >   #include <drm/drm_bridge.h>
> >   #include <drm/drm_drv.h>
> > +#include <drm/drm_encoder.h>
> >   #include <drm/drm_fbdev_dma.h>
> >   #include <drm/drm_gem_dma_helper.h>
> >   #include <drm/drm_gem_framebuffer_helper.h>
> > @@ -38,19 +41,68 @@ static const struct drm_mode_config_helper_funcs lcdif_mode_config_helpers = {
> >       .atomic_commit_tail = drm_atomic_helper_commit_tail_rpm,
> >   };
> >
> > +static const struct drm_encoder_funcs lcdif_encoder_funcs = {
> > +     .destroy = drm_encoder_cleanup,
> > +};
> > +
> >   static int lcdif_attach_bridge(struct lcdif_drm_private *lcdif)
> >   {
> > -     struct drm_device *drm = lcdif->drm;
> > +     struct device *dev = lcdif->drm->dev;
> > +     struct device_node *ep;
> >       struct drm_bridge *bridge;
> >       int ret;
> >
> > -     bridge = devm_drm_of_get_bridge(drm->dev, drm->dev->of_node, 0, 0);
> > -     if (IS_ERR(bridge))
> > -             return PTR_ERR(bridge);
> > -
> > -     ret = drm_bridge_attach(&lcdif->encoder, bridge, NULL, 0);
> > -     if (ret)
> > -             return dev_err_probe(drm->dev, ret, "Failed to attach bridge\n");
> > +     for_each_endpoint_of_node(dev->of_node, ep) {
> > +             struct device_node *remote;
> > +             struct of_endpoint of_ep;
> > +             struct drm_encoder *encoder;
> > +
> > +             remote = of_graph_get_remote_port_parent(ep);
> > +             if (!of_device_is_available(remote)) {
> > +                     of_node_put(remote);
> > +                     continue;
> > +             }
> > +             of_node_put(remote);
> > +
> > +             ret = of_graph_parse_endpoint(ep, &of_ep);
> > +             if (ret < 0) {
> > +                     dev_err(dev, "Failed to parse endpoint %pOF\n", ep);
> > +                     of_node_put(ep);
> > +                     return ret;
> > +             }
> > +
> > +             if (of_ep.id >= MAX_DISPLAYS) {
>
> Can we make the maximum number of displays, or really bridge, specific
> to IP instance instead (1 for mx8mp, 3 for mx93) ? If so, then I think
> we need to track a list of bridges in some linked list or some such
> dynamic structure, which would allow us to get rid of MAX_DISPLAYS macro.

I don't think we need to track bridges, since bridges can be found
through connector's encoder, like  lcdif_crtc_atomic_check() does
in patch 4/6.  Instead, MAX_DISPLAYS and the encoder member
in struct lcdif_drm_private can be dropped if we call devm_kzalloc()
to allocate encoders in this function.

>
> > +                     dev_warn(dev, "ingoring invalid endpoint id %u\n", of_ep.id);
>
> s@ingoring@ignoring@

Right.  But the endpoint id check is not mandatory and is better
to be dropped together with MAX_DISPLAYS.  I mean the driver
doesn't have to validate the endpoint id set in device tree.

Regards,
Liu Ying

>
> [...]