[PATCH 00/11] improve the fb_setcmap helper

[PATCH 00/11] improve the fb_setcmap helper

[Peter Rosin]

Hi!

While trying to get CLUT support for the atmel_hlcdc driver, and
specifically for the emulated fbdev interface, I received some
push-back that my feeble in-driver attempts should be solved
by the core. This is my attempt to do it right.

Boris and Daniel, was this approximately what you had in mind?

I have obviously not tested all of this with more than a compile,
but the first patch is enough to make the atmel-hlcdc driver
do what I need. The rest is just lots of removals and cleanup
made possible by the improved core.

Please test, I would not be surprised if I have fouled up some
bit-manipulation somewhere in this mostly mechanical change...

Cheers,
peda

Peter Rosin (11):
  drm/fb-helper: do a generic fb_setcmap helper in terms of crtc
    .gamma_set
  drm: amd: remove dead code and pointless local lut storage
  drm: ast: remove dead code and pointless local lut storage
  drm: cirrus: remove dead code and pointless local lut storage
  dmr: gma500: remove dead code and pointless local lut storage
  drm: i915: remove dead code and pointless local lut storage
  drm: mgag200: remove dead code and pointless local lut storage
  drm: nouveau: remove dead code and pointless local lut storage
  drm: radeon: remove dead code and pointless local lut storage
  drm: stm: remove dead code and pointless local lut storage
  drm: remove unused and redundant callbacks

 drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c      |  24 -----
 drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h    |   1 -
 drivers/gpu/drm/amd/amdgpu/dce_v10_0.c      |  27 ++----
 drivers/gpu/drm/amd/amdgpu/dce_v11_0.c      |  27 ++----
 drivers/gpu/drm/amd/amdgpu/dce_v6_0.c       |  27 ++----
 drivers/gpu/drm/amd/amdgpu/dce_v8_0.c       |  27 ++----
 drivers/gpu/drm/amd/amdgpu/dce_virtual.c    |  23 -----
 drivers/gpu/drm/ast/ast_drv.h               |   1 -
 drivers/gpu/drm/ast/ast_fb.c                |  20 -----
 drivers/gpu/drm/ast/ast_mode.c              |  26 ++----
 drivers/gpu/drm/cirrus/cirrus_drv.h         |   8 --
 drivers/gpu/drm/cirrus/cirrus_fbdev.c       |   2 -
 drivers/gpu/drm/cirrus/cirrus_mode.c        |  71 ++++-----------
 drivers/gpu/drm/drm_fb_helper.c             | 131 +++++++++-------------------
 drivers/gpu/drm/gma500/framebuffer.c        |  22 -----
 drivers/gpu/drm/gma500/gma_display.c        |  32 +++----
 drivers/gpu/drm/gma500/psb_intel_display.c  |   7 +-
 drivers/gpu/drm/gma500/psb_intel_drv.h      |   1 -
 drivers/gpu/drm/i915/intel_drv.h            |   1 -
 drivers/gpu/drm/i915/intel_fbdev.c          |  31 -------
 drivers/gpu/drm/mgag200/mgag200_drv.h       |   5 --
 drivers/gpu/drm/mgag200/mgag200_fb.c        |   2 -
 drivers/gpu/drm/mgag200/mgag200_mode.c      |  62 ++++---------
 drivers/gpu/drm/nouveau/dispnv04/crtc.c     |  26 ++----
 drivers/gpu/drm/nouveau/nouveau_crtc.h      |   3 -
 drivers/gpu/drm/nouveau/nouveau_fbcon.c     |  22 -----
 drivers/gpu/drm/nouveau/nv50_display.c      |  39 +++------
 drivers/gpu/drm/radeon/atombios_crtc.c      |   1 -
 drivers/gpu/drm/radeon/radeon_connectors.c  |   7 +-
 drivers/gpu/drm/radeon/radeon_display.c     |  71 ++++++---------
 drivers/gpu/drm/radeon/radeon_fb.c          |   2 -
 drivers/gpu/drm/radeon/radeon_legacy_crtc.c |   1 -
 drivers/gpu/drm/stm/ltdc.c                  |  12 ---
 drivers/gpu/drm/stm/ltdc.h                  |   1 -
 include/drm/drm_fb_helper.h                 |  32 -------
 include/drm/drm_modeset_helper_vtables.h    |  16 ----
 36 files changed, 171 insertions(+), 640 deletions(-)

-- 
2.1.4

[PATCH 01/11] drm/fb-helper: do a generic fb_setcmap helper in terms of crtc .gamma_set

[Peter Rosin]

This makes the redundant fb helpers .load_lut, .gamma_set and .gamma_get
totally obsolete.

I think the gamma_store can end up invalid on error. But the way I read
it, that can happen in drm_mode_gamma_set_ioctl as well, so why should
this pesky legacy fbdev stuff be any better?

drm_fb_helper_save_lut_atomic justs saves the gamma lut for later. However,
it saves it to the gamma_store which should already be up to date with what
.gamma_get would return and is thus a nop. So, zap it.

Signed-off-by: Peter Rosin <peda@axentia.se>
---
 drivers/gpu/drm/drm_fb_helper.c | 131 ++++++++++++----------------------------
 1 file changed, 40 insertions(+), 91 deletions(-)

diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 574af01..cc2d55d 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -229,22 +229,6 @@ int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
 }
 EXPORT_SYMBOL(drm_fb_helper_remove_one_connector);
 
-static void drm_fb_helper_save_lut_atomic(struct drm_crtc *crtc, struct drm_fb_helper *helper)
-{
-	uint16_t *r_base, *g_base, *b_base;
-	int i;
-
-	if (helper->funcs->gamma_get == NULL)
-		return;
-
-	r_base = crtc->gamma_store;
-	g_base = r_base + crtc->gamma_size;
-	b_base = g_base + crtc->gamma_size;
-
-	for (i = 0; i < crtc->gamma_size; i++)
-		helper->funcs->gamma_get(crtc, &r_base[i], &g_base[i], &b_base[i], i);
-}
-
 static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc)
 {
 	uint16_t *r_base, *g_base, *b_base;
@@ -285,7 +269,6 @@ int drm_fb_helper_debug_enter(struct fb_info *info)
 			if (drm_drv_uses_atomic_modeset(mode_set->crtc->dev))
 				continue;
 
-			drm_fb_helper_save_lut_atomic(mode_set->crtc, helper);
 			funcs->mode_set_base_atomic(mode_set->crtc,
 						    mode_set->fb,
 						    mode_set->x,
@@ -1167,50 +1150,6 @@ void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
 }
 EXPORT_SYMBOL(drm_fb_helper_set_suspend_unlocked);
 
-static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green,
-		     u16 blue, u16 regno, struct fb_info *info)
-{
-	struct drm_fb_helper *fb_helper = info->par;
-	struct drm_framebuffer *fb = fb_helper->fb;
-
-	if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
-		u32 *palette;
-		u32 value;
-		/* place color in psuedopalette */
-		if (regno > 16)
-			return -EINVAL;
-		palette = (u32 *)info->pseudo_palette;
-		red >>= (16 - info->var.red.length);
-		green >>= (16 - info->var.green.length);
-		blue >>= (16 - info->var.blue.length);
-		value = (red << info->var.red.offset) |
-			(green << info->var.green.offset) |
-			(blue << info->var.blue.offset);
-		if (info->var.transp.length > 0) {
-			u32 mask = (1 << info->var.transp.length) - 1;
-
-			mask <<= info->var.transp.offset;
-			value |= mask;
-		}
-		palette[regno] = value;
-		return 0;
-	}
-
-	/*
-	 * The driver really shouldn't advertise pseudo/directcolor
-	 * visuals if it can't deal with the palette.
-	 */
-	if (WARN_ON(!fb_helper->funcs->gamma_set ||
-		    !fb_helper->funcs->gamma_get))
-		return -EINVAL;
-
-	WARN_ON(fb->format->cpp[0] != 1);
-
-	fb_helper->funcs->gamma_set(crtc, red, green, blue, regno);
-
-	return 0;
-}
-
 /**
  * drm_fb_helper_setcmap - implementation for &fb_ops.fb_setcmap
  * @cmap: cmap to set
@@ -1220,51 +1159,61 @@ int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
 {
 	struct drm_fb_helper *fb_helper = info->par;
 	struct drm_device *dev = fb_helper->dev;
-	const struct drm_crtc_helper_funcs *crtc_funcs;
-	u16 *red, *green, *blue, *transp;
+	struct drm_modeset_acquire_ctx ctx;
 	struct drm_crtc *crtc;
-	int i, j, rc = 0;
-	int start;
+	u16 *r, *g, *b;
+	int i, ret;
 
 	if (oops_in_progress)
 		return -EBUSY;
 
-	drm_modeset_lock_all(dev);
+	if (cmap->start + cmap->len < cmap->start)
+		return -EINVAL;
+
+	drm_modeset_acquire_init(&ctx, 0);
+retry:
+	ret = drm_modeset_lock_all_ctx(dev, &ctx);
+	if (ret)
+		goto out;
 	if (!drm_fb_helper_is_bound(fb_helper)) {
-		drm_modeset_unlock_all(dev);
-		return -EBUSY;
+		ret = -EBUSY;
+		goto out;
 	}
 
 	for (i = 0; i < fb_helper->crtc_count; i++) {
 		crtc = fb_helper->crtc_info[i].mode_set.crtc;
-		crtc_funcs = crtc->helper_private;
-
-		red = cmap->red;
-		green = cmap->green;
-		blue = cmap->blue;
-		transp = cmap->transp;
-		start = cmap->start;
+		if (!crtc->funcs->gamma_set || !crtc->gamma_size) {
+			ret = -EINVAL;
+			goto out;
+		}
 
-		for (j = 0; j < cmap->len; j++) {
-			u16 hred, hgreen, hblue, htransp = 0xffff;
+		if (cmap->start + cmap->len > crtc->gamma_size) {
+			ret = -EINVAL;
+			goto out;
+		}
 
-			hred = *red++;
-			hgreen = *green++;
-			hblue = *blue++;
+		r = crtc->gamma_store;
+		g = r + crtc->gamma_size;
+		b = g + crtc->gamma_size;
 
-			if (transp)
-				htransp = *transp++;
+		memcpy(r + cmap->start, cmap->red, cmap->len * sizeof(u16));
+		memcpy(g + cmap->start, cmap->green, cmap->len * sizeof(u16));
+		memcpy(b + cmap->start, cmap->blue, cmap->len * sizeof(u16));
 
-			rc = setcolreg(crtc, hred, hgreen, hblue, start++, info);
-			if (rc)
-				goto out;
-		}
-		if (crtc_funcs->load_lut)
-			crtc_funcs->load_lut(crtc);
+		ret = crtc->funcs->gamma_set(crtc, r, g, b,
+					     crtc->gamma_size, &ctx);
+		if (ret)
+			break;
 	}
- out:
-	drm_modeset_unlock_all(dev);
-	return rc;
+out:
+	if (ret == -EDEADLK) {
+		drm_modeset_backoff(&ctx);
+		goto retry;
+	}
+	drm_modeset_drop_locks(&ctx);
+	drm_modeset_acquire_fini(&ctx);
+
+	return ret;
 }
 EXPORT_SYMBOL(drm_fb_helper_setcmap);
 
-- 
2.1.4

[PATCH 02/11] drm: amd: remove dead code and pointless local lut storage

[Peter Rosin]

The redundant fb helpers .load_lut, .gamma_set and .gamma_get are
no longer used. Remove the dead code and hook up the crtc .gamma_set
to use the crtc gamma_store directly instead of duplicating that
info locally.

Signed-off-by: Peter Rosin <peda@axentia.se>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c   | 24 ------------------------
 drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h |  1 -
 drivers/gpu/drm/amd/amdgpu/dce_v10_0.c   | 27 +++++++--------------------
 drivers/gpu/drm/amd/amdgpu/dce_v11_0.c   | 27 +++++++--------------------
 drivers/gpu/drm/amd/amdgpu/dce_v6_0.c    | 27 +++++++--------------------
 drivers/gpu/drm/amd/amdgpu/dce_v8_0.c    | 27 +++++++--------------------
 drivers/gpu/drm/amd/amdgpu/dce_virtual.c | 23 -----------------------
 7 files changed, 28 insertions(+), 128 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c
index c0d8c6f..7dc3780 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c
@@ -312,31 +312,7 @@ static int amdgpu_fbdev_destroy(struct drm_device *dev, struct amdgpu_fbdev *rfb
 	return 0;
 }
 
-/** Sets the color ramps on behalf of fbcon */
-static void amdgpu_crtc_fb_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
-				      u16 blue, int regno)
-{
-	struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc);
-
-	amdgpu_crtc->lut_r[regno] = red >> 6;
-	amdgpu_crtc->lut_g[regno] = green >> 6;
-	amdgpu_crtc->lut_b[regno] = blue >> 6;
-}
-
-/** Gets the color ramps on behalf of fbcon */
-static void amdgpu_crtc_fb_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
-				      u16 *blue, int regno)
-{
-	struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc);
-
-	*red = amdgpu_crtc->lut_r[regno] << 6;
-	*green = amdgpu_crtc->lut_g[regno] << 6;
-	*blue = amdgpu_crtc->lut_b[regno] << 6;
-}
-
 static const struct drm_fb_helper_funcs amdgpu_fb_helper_funcs = {
-	.gamma_set = amdgpu_crtc_fb_gamma_set,
-	.gamma_get = amdgpu_crtc_fb_gamma_get,
 	.fb_probe = amdgpufb_create,
 };
 
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
index 43a9d3a..39f7eda 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
@@ -369,7 +369,6 @@ struct amdgpu_atom_ss {
 struct amdgpu_crtc {
 	struct drm_crtc base;
 	int crtc_id;
-	u16 lut_r[256], lut_g[256], lut_b[256];
 	bool enabled;
 	bool can_tile;
 	uint32_t crtc_offset;
diff --git a/drivers/gpu/drm/amd/amdgpu/dce_v10_0.c b/drivers/gpu/drm/amd/amdgpu/dce_v10_0.c
index 3c62c45..8e8c028 100644
--- a/drivers/gpu/drm/amd/amdgpu/dce_v10_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/dce_v10_0.c
@@ -2264,6 +2264,7 @@ static void dce_v10_0_crtc_load_lut(struct drm_crtc *crtc)
 	struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc);
 	struct drm_device *dev = crtc->dev;
 	struct amdgpu_device *adev = dev->dev_private;
+	u16 *r, *g, *b;
 	int i;
 	u32 tmp;
 
@@ -2301,11 +2302,14 @@ static void dce_v10_0_crtc_load_lut(struct drm_crtc *crtc)
 	WREG32(mmDC_LUT_WRITE_EN_MASK + amdgpu_crtc->crtc_offset, 0x00000007);
 
 	WREG32(mmDC_LUT_RW_INDEX + amdgpu_crtc->crtc_offset, 0);
+	r = crtc->gamma_store;
+	g = r + crtc->gamma_size;
+	b = g + crtc->gamma_size;
 	for (i = 0; i < 256; i++) {
 		WREG32(mmDC_LUT_30_COLOR + amdgpu_crtc->crtc_offset,
-		       (amdgpu_crtc->lut_r[i] << 20) |
-		       (amdgpu_crtc->lut_g[i] << 10) |
-		       (amdgpu_crtc->lut_b[i] << 0));
+		       ((*r++ & 0xffc0) << 14) |
+		       ((*g++ & 0xffc0) << 4) |
+		       (*b++ >> 6));
 	}
 
 	tmp = RREG32(mmDEGAMMA_CONTROL + amdgpu_crtc->crtc_offset);
@@ -2621,15 +2625,6 @@ static int dce_v10_0_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
 				    u16 *blue, uint32_t size,
 				    struct drm_modeset_acquire_ctx *ctx)
 {
-	struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc);
-	int i;
-
-	/* userspace palettes are always correct as is */
-	for (i = 0; i < size; i++) {
-		amdgpu_crtc->lut_r[i] = red[i] >> 6;
-		amdgpu_crtc->lut_g[i] = green[i] >> 6;
-		amdgpu_crtc->lut_b[i] = blue[i] >> 6;
-	}
 	dce_v10_0_crtc_load_lut(crtc);
 
 	return 0;
@@ -2841,14 +2836,12 @@ static const struct drm_crtc_helper_funcs dce_v10_0_crtc_helper_funcs = {
 	.mode_set_base_atomic = dce_v10_0_crtc_set_base_atomic,
 	.prepare = dce_v10_0_crtc_prepare,
 	.commit = dce_v10_0_crtc_commit,
-	.load_lut = dce_v10_0_crtc_load_lut,
 	.disable = dce_v10_0_crtc_disable,
 };
 
 static int dce_v10_0_crtc_init(struct amdgpu_device *adev, int index)
 {
 	struct amdgpu_crtc *amdgpu_crtc;
-	int i;
 
 	amdgpu_crtc = kzalloc(sizeof(struct amdgpu_crtc) +
 			      (AMDGPUFB_CONN_LIMIT * sizeof(struct drm_connector *)), GFP_KERNEL);
@@ -2866,12 +2859,6 @@ static int dce_v10_0_crtc_init(struct amdgpu_device *adev, int index)
 	adev->ddev->mode_config.cursor_width = amdgpu_crtc->max_cursor_width;
 	adev->ddev->mode_config.cursor_height = amdgpu_crtc->max_cursor_height;
 
-	for (i = 0; i < 256; i++) {
-		amdgpu_crtc->lut_r[i] = i << 2;
-		amdgpu_crtc->lut_g[i] = i << 2;
-		amdgpu_crtc->lut_b[i] = i << 2;
-	}
-
 	switch (amdgpu_crtc->crtc_id) {
 	case 0:
 	default:
diff --git a/drivers/gpu/drm/amd/amdgpu/dce_v11_0.c b/drivers/gpu/drm/amd/amdgpu/dce_v11_0.c
index c8ed0fa..2280376 100644
--- a/drivers/gpu/drm/amd/amdgpu/dce_v11_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/dce_v11_0.c
@@ -2248,6 +2248,7 @@ static void dce_v11_0_crtc_load_lut(struct drm_crtc *crtc)
 	struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc);
 	struct drm_device *dev = crtc->dev;
 	struct amdgpu_device *adev = dev->dev_private;
+	u16 *r, *g, *b;
 	int i;
 	u32 tmp;
 
@@ -2279,11 +2280,14 @@ static void dce_v11_0_crtc_load_lut(struct drm_crtc *crtc)
 	WREG32(mmDC_LUT_WRITE_EN_MASK + amdgpu_crtc->crtc_offset, 0x00000007);
 
 	WREG32(mmDC_LUT_RW_INDEX + amdgpu_crtc->crtc_offset, 0);
+	r = crtc->gamma_store;
+	g = r + crtc->gamma_size;
+	b = g + crtc->gamma_size;
 	for (i = 0; i < 256; i++) {
 		WREG32(mmDC_LUT_30_COLOR + amdgpu_crtc->crtc_offset,
-		       (amdgpu_crtc->lut_r[i] << 20) |
-		       (amdgpu_crtc->lut_g[i] << 10) |
-		       (amdgpu_crtc->lut_b[i] << 0));
+		       ((*r++ & 0xffc0) << 14) |
+		       ((*g++ & 0xffc0) << 4) |
+		       (*b++ >> 6));
 	}
 
 	tmp = RREG32(mmDEGAMMA_CONTROL + amdgpu_crtc->crtc_offset);
@@ -2641,15 +2645,6 @@ static int dce_v11_0_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
 				    u16 *blue, uint32_t size,
 				    struct drm_modeset_acquire_ctx *ctx)
 {
-	struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc);
-	int i;
-
-	/* userspace palettes are always correct as is */
-	for (i = 0; i < size; i++) {
-		amdgpu_crtc->lut_r[i] = red[i] >> 6;
-		amdgpu_crtc->lut_g[i] = green[i] >> 6;
-		amdgpu_crtc->lut_b[i] = blue[i] >> 6;
-	}
 	dce_v11_0_crtc_load_lut(crtc);
 
 	return 0;
@@ -2889,14 +2884,12 @@ static const struct drm_crtc_helper_funcs dce_v11_0_crtc_helper_funcs = {
 	.mode_set_base_atomic = dce_v11_0_crtc_set_base_atomic,
 	.prepare = dce_v11_0_crtc_prepare,
 	.commit = dce_v11_0_crtc_commit,
-	.load_lut = dce_v11_0_crtc_load_lut,
 	.disable = dce_v11_0_crtc_disable,
 };
 
 static int dce_v11_0_crtc_init(struct amdgpu_device *adev, int index)
 {
 	struct amdgpu_crtc *amdgpu_crtc;
-	int i;
 
 	amdgpu_crtc = kzalloc(sizeof(struct amdgpu_crtc) +
 			      (AMDGPUFB_CONN_LIMIT * sizeof(struct drm_connector *)), GFP_KERNEL);
@@ -2914,12 +2907,6 @@ static int dce_v11_0_crtc_init(struct amdgpu_device *adev, int index)
 	adev->ddev->mode_config.cursor_width = amdgpu_crtc->max_cursor_width;
 	adev->ddev->mode_config.cursor_height = amdgpu_crtc->max_cursor_height;
 
-	for (i = 0; i < 256; i++) {
-		amdgpu_crtc->lut_r[i] = i << 2;
-		amdgpu_crtc->lut_g[i] = i << 2;
-		amdgpu_crtc->lut_b[i] = i << 2;
-	}
-
 	switch (amdgpu_crtc->crtc_id) {
 	case 0:
 	default:
diff --git a/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c b/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c
index 3f3a254..6d957f0 100644
--- a/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c
@@ -1679,6 +1679,7 @@ static void dce_v6_0_crtc_load_lut(struct drm_crtc *crtc)
 	struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc);
 	struct drm_device *dev = crtc->dev;
 	struct amdgpu_device *adev = dev->dev_private;
+	u16 *r, *g, *b;
 	int i;
 
 	DRM_DEBUG_KMS("%d\n", amdgpu_crtc->crtc_id);
@@ -1708,11 +1709,14 @@ static void dce_v6_0_crtc_load_lut(struct drm_crtc *crtc)
 	WREG32(mmDC_LUT_WRITE_EN_MASK + amdgpu_crtc->crtc_offset, 0x00000007);
 
 	WREG32(mmDC_LUT_RW_INDEX + amdgpu_crtc->crtc_offset, 0);
+	r = crtc->gamma_store;
+	g = r + crtc->gamma_size;
+	b = g + crtc->gamma_size;
 	for (i = 0; i < 256; i++) {
 		WREG32(mmDC_LUT_30_COLOR + amdgpu_crtc->crtc_offset,
-		       (amdgpu_crtc->lut_r[i] << 20) |
-		       (amdgpu_crtc->lut_g[i] << 10) |
-		       (amdgpu_crtc->lut_b[i] << 0));
+		       ((*r++ & 0xffc0) << 14) |
+		       ((*g++ & 0xffc0) << 4) |
+		       (*b++ >> 6));
 	}
 
 	WREG32(mmDEGAMMA_CONTROL + amdgpu_crtc->crtc_offset,
@@ -1993,15 +1997,6 @@ static int dce_v6_0_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
 				   u16 *blue, uint32_t size,
 				   struct drm_modeset_acquire_ctx *ctx)
 {
-	struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc);
-	int i;
-
-	/* userspace palettes are always correct as is */
-	for (i = 0; i < size; i++) {
-		amdgpu_crtc->lut_r[i] = red[i] >> 6;
-		amdgpu_crtc->lut_g[i] = green[i] >> 6;
-		amdgpu_crtc->lut_b[i] = blue[i] >> 6;
-	}
 	dce_v6_0_crtc_load_lut(crtc);
 
 	return 0;
@@ -2209,14 +2204,12 @@ static const struct drm_crtc_helper_funcs dce_v6_0_crtc_helper_funcs = {
 	.mode_set_base_atomic = dce_v6_0_crtc_set_base_atomic,
 	.prepare = dce_v6_0_crtc_prepare,
 	.commit = dce_v6_0_crtc_commit,
-	.load_lut = dce_v6_0_crtc_load_lut,
 	.disable = dce_v6_0_crtc_disable,
 };
 
 static int dce_v6_0_crtc_init(struct amdgpu_device *adev, int index)
 {
 	struct amdgpu_crtc *amdgpu_crtc;
-	int i;
 
 	amdgpu_crtc = kzalloc(sizeof(struct amdgpu_crtc) +
 			      (AMDGPUFB_CONN_LIMIT * sizeof(struct drm_connector *)), GFP_KERNEL);
@@ -2234,12 +2227,6 @@ static int dce_v6_0_crtc_init(struct amdgpu_device *adev, int index)
 	adev->ddev->mode_config.cursor_width = amdgpu_crtc->max_cursor_width;
 	adev->ddev->mode_config.cursor_height = amdgpu_crtc->max_cursor_height;
 
-	for (i = 0; i < 256; i++) {
-		amdgpu_crtc->lut_r[i] = i << 2;
-		amdgpu_crtc->lut_g[i] = i << 2;
-		amdgpu_crtc->lut_b[i] = i << 2;
-	}
-
 	amdgpu_crtc->crtc_offset = crtc_offsets[amdgpu_crtc->crtc_id];
 
 	amdgpu_crtc->pll_id = ATOM_PPLL_INVALID;
diff --git a/drivers/gpu/drm/amd/amdgpu/dce_v8_0.c b/drivers/gpu/drm/amd/amdgpu/dce_v8_0.c
index 3e90c19..a946bf7 100644
--- a/drivers/gpu/drm/amd/amdgpu/dce_v8_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/dce_v8_0.c
@@ -2121,6 +2121,7 @@ static void dce_v8_0_crtc_load_lut(struct drm_crtc *crtc)
 	struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc);
 	struct drm_device *dev = crtc->dev;
 	struct amdgpu_device *adev = dev->dev_private;
+	u16 *r, *g, *b;
 	int i;
 
 	DRM_DEBUG_KMS("%d\n", amdgpu_crtc->crtc_id);
@@ -2150,11 +2151,14 @@ static void dce_v8_0_crtc_load_lut(struct drm_crtc *crtc)
 	WREG32(mmDC_LUT_WRITE_EN_MASK + amdgpu_crtc->crtc_offset, 0x00000007);
 
 	WREG32(mmDC_LUT_RW_INDEX + amdgpu_crtc->crtc_offset, 0);
+	r = crtc->gamma_store;
+	g = r + crtc->gamma_size;
+	b = g + crtc->gamma_size;
 	for (i = 0; i < 256; i++) {
 		WREG32(mmDC_LUT_30_COLOR + amdgpu_crtc->crtc_offset,
-		       (amdgpu_crtc->lut_r[i] << 20) |
-		       (amdgpu_crtc->lut_g[i] << 10) |
-		       (amdgpu_crtc->lut_b[i] << 0));
+		       ((*r++ & 0xffc0) << 14) |
+		       ((*g++ & 0xffc0) << 4) |
+		       (*b++ >> 6));
 	}
 
 	WREG32(mmDEGAMMA_CONTROL + amdgpu_crtc->crtc_offset,
@@ -2472,15 +2476,6 @@ static int dce_v8_0_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
 				   u16 *blue, uint32_t size,
 				   struct drm_modeset_acquire_ctx *ctx)
 {
-	struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc);
-	int i;
-
-	/* userspace palettes are always correct as is */
-	for (i = 0; i < size; i++) {
-		amdgpu_crtc->lut_r[i] = red[i] >> 6;
-		amdgpu_crtc->lut_g[i] = green[i] >> 6;
-		amdgpu_crtc->lut_b[i] = blue[i] >> 6;
-	}
 	dce_v8_0_crtc_load_lut(crtc);
 
 	return 0;
@@ -2699,14 +2694,12 @@ static const struct drm_crtc_helper_funcs dce_v8_0_crtc_helper_funcs = {
 	.mode_set_base_atomic = dce_v8_0_crtc_set_base_atomic,
 	.prepare = dce_v8_0_crtc_prepare,
 	.commit = dce_v8_0_crtc_commit,
-	.load_lut = dce_v8_0_crtc_load_lut,
 	.disable = dce_v8_0_crtc_disable,
 };
 
 static int dce_v8_0_crtc_init(struct amdgpu_device *adev, int index)
 {
 	struct amdgpu_crtc *amdgpu_crtc;
-	int i;
 
 	amdgpu_crtc = kzalloc(sizeof(struct amdgpu_crtc) +
 			      (AMDGPUFB_CONN_LIMIT * sizeof(struct drm_connector *)), GFP_KERNEL);
@@ -2724,12 +2717,6 @@ static int dce_v8_0_crtc_init(struct amdgpu_device *adev, int index)
 	adev->ddev->mode_config.cursor_width = amdgpu_crtc->max_cursor_width;
 	adev->ddev->mode_config.cursor_height = amdgpu_crtc->max_cursor_height;
 
-	for (i = 0; i < 256; i++) {
-		amdgpu_crtc->lut_r[i] = i << 2;
-		amdgpu_crtc->lut_g[i] = i << 2;
-		amdgpu_crtc->lut_b[i] = i << 2;
-	}
-
 	amdgpu_crtc->crtc_offset = crtc_offsets[amdgpu_crtc->crtc_id];
 
 	amdgpu_crtc->pll_id = ATOM_PPLL_INVALID;
diff --git a/drivers/gpu/drm/amd/amdgpu/dce_virtual.c b/drivers/gpu/drm/amd/amdgpu/dce_virtual.c
index 90bb083..ecf34bc 100644
--- a/drivers/gpu/drm/amd/amdgpu/dce_virtual.c
+++ b/drivers/gpu/drm/amd/amdgpu/dce_virtual.c
@@ -168,16 +168,6 @@ static int dce_virtual_crtc_gamma_set(struct drm_crtc *crtc, u16 *red,
 				      u16 *green, u16 *blue, uint32_t size,
 				      struct drm_modeset_acquire_ctx *ctx)
 {
-	struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc);
-	int i;
-
-	/* userspace palettes are always correct as is */
-	for (i = 0; i < size; i++) {
-		amdgpu_crtc->lut_r[i] = red[i] >> 6;
-		amdgpu_crtc->lut_g[i] = green[i] >> 6;
-		amdgpu_crtc->lut_b[i] = blue[i] >> 6;
-	}
-
 	return 0;
 }
 
@@ -289,11 +279,6 @@ static int dce_virtual_crtc_set_base(struct drm_crtc *crtc, int x, int y,
 	return 0;
 }
 
-static void dce_virtual_crtc_load_lut(struct drm_crtc *crtc)
-{
-	return;
-}
-
 static int dce_virtual_crtc_set_base_atomic(struct drm_crtc *crtc,
 					 struct drm_framebuffer *fb,
 					 int x, int y, enum mode_set_atomic state)
@@ -309,14 +294,12 @@ static const struct drm_crtc_helper_funcs dce_virtual_crtc_helper_funcs = {
 	.mode_set_base_atomic = dce_virtual_crtc_set_base_atomic,
 	.prepare = dce_virtual_crtc_prepare,
 	.commit = dce_virtual_crtc_commit,
-	.load_lut = dce_virtual_crtc_load_lut,
 	.disable = dce_virtual_crtc_disable,
 };
 
 static int dce_virtual_crtc_init(struct amdgpu_device *adev, int index)
 {
 	struct amdgpu_crtc *amdgpu_crtc;
-	int i;
 
 	amdgpu_crtc = kzalloc(sizeof(struct amdgpu_crtc) +
 			      (AMDGPUFB_CONN_LIMIT * sizeof(struct drm_connector *)), GFP_KERNEL);
@@ -329,12 +312,6 @@ static int dce_virtual_crtc_init(struct amdgpu_device *adev, int index)
 	amdgpu_crtc->crtc_id = index;
 	adev->mode_info.crtcs[index] = amdgpu_crtc;
 
-	for (i = 0; i < 256; i++) {
-		amdgpu_crtc->lut_r[i] = i << 2;
-		amdgpu_crtc->lut_g[i] = i << 2;
-		amdgpu_crtc->lut_b[i] = i << 2;
-	}
-
 	amdgpu_crtc->pll_id = ATOM_PPLL_INVALID;
 	amdgpu_crtc->encoder = NULL;
 	amdgpu_crtc->connector = NULL;
-- 
2.1.4

[PATCH 03/11] drm: ast: remove dead code and pointless local lut storage

[Peter Rosin]

The redundant fb helpers .load_lut, .gamma_set and .gamma_get are
no longer used. Remove the dead code and hook up the crtc .gamma_set
to use the crtc gamma_store directly instead of duplicating that
info locally.

Signed-off-by: Peter Rosin <peda@axentia.se>
---
 drivers/gpu/drm/ast/ast_drv.h  |  1 -
 drivers/gpu/drm/ast/ast_fb.c   | 20 --------------------
 drivers/gpu/drm/ast/ast_mode.c | 26 ++++++--------------------
 3 files changed, 6 insertions(+), 41 deletions(-)

diff --git a/drivers/gpu/drm/ast/ast_drv.h b/drivers/gpu/drm/ast/ast_drv.h
index 8880f0b..569a148 100644
--- a/drivers/gpu/drm/ast/ast_drv.h
+++ b/drivers/gpu/drm/ast/ast_drv.h
@@ -245,7 +245,6 @@ struct ast_connector {
 
 struct ast_crtc {
 	struct drm_crtc base;
-	u8 lut_r[256], lut_g[256], lut_b[256];
 	struct drm_gem_object *cursor_bo;
 	uint64_t cursor_addr;
 	int cursor_width, cursor_height;
diff --git a/drivers/gpu/drm/ast/ast_fb.c b/drivers/gpu/drm/ast/ast_fb.c
index 4ad4acd..dbabcac 100644
--- a/drivers/gpu/drm/ast/ast_fb.c
+++ b/drivers/gpu/drm/ast/ast_fb.c
@@ -255,27 +255,7 @@ static int astfb_create(struct drm_fb_helper *helper,
 	return ret;
 }
 
-static void ast_fb_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
-			       u16 blue, int regno)
-{
-	struct ast_crtc *ast_crtc = to_ast_crtc(crtc);
-	ast_crtc->lut_r[regno] = red >> 8;
-	ast_crtc->lut_g[regno] = green >> 8;
-	ast_crtc->lut_b[regno] = blue >> 8;
-}
-
-static void ast_fb_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
-			       u16 *blue, int regno)
-{
-	struct ast_crtc *ast_crtc = to_ast_crtc(crtc);
-	*red = ast_crtc->lut_r[regno] << 8;
-	*green = ast_crtc->lut_g[regno] << 8;
-	*blue = ast_crtc->lut_b[regno] << 8;
-}
-
 static const struct drm_fb_helper_funcs ast_fb_helper_funcs = {
-	.gamma_set = ast_fb_gamma_set,
-	.gamma_get = ast_fb_gamma_get,
 	.fb_probe = astfb_create,
 };
 
diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index aaef0a6..724c16b 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -63,15 +63,18 @@ static inline void ast_load_palette_index(struct ast_private *ast,
 static void ast_crtc_load_lut(struct drm_crtc *crtc)
 {
 	struct ast_private *ast = crtc->dev->dev_private;
-	struct ast_crtc *ast_crtc = to_ast_crtc(crtc);
+	u16 *r, *g, *b;
 	int i;
 
 	if (!crtc->enabled)
 		return;
 
+	r = crtc->gamma_store;
+	g = r + crtc->gamma_size;
+	b = g + crtc->gamma_size;
+
 	for (i = 0; i < 256; i++)
-		ast_load_palette_index(ast, i, ast_crtc->lut_r[i],
-				       ast_crtc->lut_g[i], ast_crtc->lut_b[i]);
+		ast_load_palette_index(ast, i, *r++ >> 8, *g++ >> 8, *b++ >> 8);
 }
 
 static bool ast_get_vbios_mode_info(struct drm_crtc *crtc, struct drm_display_mode *mode,
@@ -633,7 +636,6 @@ static const struct drm_crtc_helper_funcs ast_crtc_helper_funcs = {
 	.mode_set = ast_crtc_mode_set,
 	.mode_set_base = ast_crtc_mode_set_base,
 	.disable = ast_crtc_disable,
-	.load_lut = ast_crtc_load_lut,
 	.prepare = ast_crtc_prepare,
 	.commit = ast_crtc_commit,
 
@@ -648,15 +650,6 @@ static int ast_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
 			      u16 *blue, uint32_t size,
 			      struct drm_modeset_acquire_ctx *ctx)
 {
-	struct ast_crtc *ast_crtc = to_ast_crtc(crtc);
-	int i;
-
-	/* userspace palettes are always correct as is */
-	for (i = 0; i < size; i++) {
-		ast_crtc->lut_r[i] = red[i] >> 8;
-		ast_crtc->lut_g[i] = green[i] >> 8;
-		ast_crtc->lut_b[i] = blue[i] >> 8;
-	}
 	ast_crtc_load_lut(crtc);
 
 	return 0;
@@ -681,7 +674,6 @@ static const struct drm_crtc_funcs ast_crtc_funcs = {
 static int ast_crtc_init(struct drm_device *dev)
 {
 	struct ast_crtc *crtc;
-	int i;
 
 	crtc = kzalloc(sizeof(struct ast_crtc), GFP_KERNEL);
 	if (!crtc)
@@ -690,12 +682,6 @@ static int ast_crtc_init(struct drm_device *dev)
 	drm_crtc_init(dev, &crtc->base, &ast_crtc_funcs);
 	drm_mode_crtc_set_gamma_size(&crtc->base, 256);
 	drm_crtc_helper_add(&crtc->base, &ast_crtc_helper_funcs);
-
-	for (i = 0; i < 256; i++) {
-		crtc->lut_r[i] = i;
-		crtc->lut_g[i] = i;
-		crtc->lut_b[i] = i;
-	}
 	return 0;
 }
 
-- 
2.1.4

[PATCH 04/11] drm: cirrus: remove dead code and pointless local lut storage

[Peter Rosin]

The redundant fb helpers .load_lut, .gamma_set and .gamma_get are
no longer used. Remove the dead code and hook up the crtc .gamma_set
to use the crtc gamma_store directly instead of duplicating that
info locally.

Signed-off-by: Peter Rosin <peda@axentia.se>
---
 drivers/gpu/drm/cirrus/cirrus_drv.h   |  8 ----
 drivers/gpu/drm/cirrus/cirrus_fbdev.c |  2 -
 drivers/gpu/drm/cirrus/cirrus_mode.c  | 71 ++++++++---------------------------
 3 files changed, 16 insertions(+), 65 deletions(-)

diff --git a/drivers/gpu/drm/cirrus/cirrus_drv.h b/drivers/gpu/drm/cirrus/cirrus_drv.h
index 8690352..be2d7e48 100644
--- a/drivers/gpu/drm/cirrus/cirrus_drv.h
+++ b/drivers/gpu/drm/cirrus/cirrus_drv.h
@@ -96,7 +96,6 @@
 
 struct cirrus_crtc {
 	struct drm_crtc			base;
-	u8				lut_r[256], lut_g[256], lut_b[256];
 	int				last_dpms;
 	bool				enabled;
 };
@@ -180,13 +179,6 @@ cirrus_bo(struct ttm_buffer_object *bo)
 #define to_cirrus_obj(x) container_of(x, struct cirrus_gem_object, base)
 #define DRM_FILE_PAGE_OFFSET (0x100000000ULL >> PAGE_SHIFT)
 
-				/* cirrus_mode.c */
-void cirrus_crtc_fb_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
-			     u16 blue, int regno);
-void cirrus_crtc_fb_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
-			     u16 *blue, int regno);
-
-
 				/* cirrus_main.c */
 int cirrus_device_init(struct cirrus_device *cdev,
 		      struct drm_device *ddev,
diff --git a/drivers/gpu/drm/cirrus/cirrus_fbdev.c b/drivers/gpu/drm/cirrus/cirrus_fbdev.c
index 7fa58ee..1fedab0 100644
--- a/drivers/gpu/drm/cirrus/cirrus_fbdev.c
+++ b/drivers/gpu/drm/cirrus/cirrus_fbdev.c
@@ -265,8 +265,6 @@ static int cirrus_fbdev_destroy(struct drm_device *dev,
 }
 
 static const struct drm_fb_helper_funcs cirrus_fb_helper_funcs = {
-	.gamma_set = cirrus_crtc_fb_gamma_set,
-	.gamma_get = cirrus_crtc_fb_gamma_get,
 	.fb_probe = cirrusfb_create,
 };
 
diff --git a/drivers/gpu/drm/cirrus/cirrus_mode.c b/drivers/gpu/drm/cirrus/cirrus_mode.c
index 53f6f0f..a4c4a46 100644
--- a/drivers/gpu/drm/cirrus/cirrus_mode.c
+++ b/drivers/gpu/drm/cirrus/cirrus_mode.c
@@ -31,25 +31,6 @@
  * This file contains setup code for the CRTC.
  */
 
-static void cirrus_crtc_load_lut(struct drm_crtc *crtc)
-{
-	struct cirrus_crtc *cirrus_crtc = to_cirrus_crtc(crtc);
-	struct drm_device *dev = crtc->dev;
-	struct cirrus_device *cdev = dev->dev_private;
-	int i;
-
-	if (!crtc->enabled)
-		return;
-
-	for (i = 0; i < CIRRUS_LUT_SIZE; i++) {
-		/* VGA registers */
-		WREG8(PALETTE_INDEX, i);
-		WREG8(PALETTE_DATA, cirrus_crtc->lut_r[i]);
-		WREG8(PALETTE_DATA, cirrus_crtc->lut_g[i]);
-		WREG8(PALETTE_DATA, cirrus_crtc->lut_b[i]);
-	}
-}
-
 /*
  * The DRM core requires DPMS functions, but they make little sense in our
  * case and so are just stubs
@@ -330,15 +311,25 @@ static int cirrus_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
 				 u16 *blue, uint32_t size,
 				 struct drm_modeset_acquire_ctx *ctx)
 {
-	struct cirrus_crtc *cirrus_crtc = to_cirrus_crtc(crtc);
+	struct drm_device *dev = crtc->dev;
+	struct cirrus_device *cdev = dev->dev_private;
+	u16 *r, *g, *b;
 	int i;
 
-	for (i = 0; i < size; i++) {
-		cirrus_crtc->lut_r[i] = red[i];
-		cirrus_crtc->lut_g[i] = green[i];
-		cirrus_crtc->lut_b[i] = blue[i];
+	if (!crtc->enabled)
+		return 0;
+
+	r = crtc->gamma_store;
+	g = r + crtc->gamma_size;
+	b = g + crtc->gamma_size;
+
+	for (i = 0; i < CIRRUS_LUT_SIZE; i++) {
+		/* VGA registers */
+		WREG8(PALETTE_INDEX, i);
+		WREG8(PALETTE_DATA, *r++ >> 8);
+		WREG8(PALETTE_DATA, *g++ >> 8);
+		WREG8(PALETTE_DATA, *b++ >> 8);
 	}
-	cirrus_crtc_load_lut(crtc);
 
 	return 0;
 }
@@ -365,7 +356,6 @@ static const struct drm_crtc_helper_funcs cirrus_helper_funcs = {
 	.mode_set_base = cirrus_crtc_mode_set_base,
 	.prepare = cirrus_crtc_prepare,
 	.commit = cirrus_crtc_commit,
-	.load_lut = cirrus_crtc_load_lut,
 };
 
 /* CRTC setup */
@@ -373,7 +363,6 @@ static void cirrus_crtc_init(struct drm_device *dev)
 {
 	struct cirrus_device *cdev = dev->dev_private;
 	struct cirrus_crtc *cirrus_crtc;
-	int i;
 
 	cirrus_crtc = kzalloc(sizeof(struct cirrus_crtc) +
 			      (CIRRUSFB_CONN_LIMIT * sizeof(struct drm_connector *)),
@@ -387,37 +376,9 @@ static void cirrus_crtc_init(struct drm_device *dev)
 	drm_mode_crtc_set_gamma_size(&cirrus_crtc->base, CIRRUS_LUT_SIZE);
 	cdev->mode_info.crtc = cirrus_crtc;
 
-	for (i = 0; i < CIRRUS_LUT_SIZE; i++) {
-		cirrus_crtc->lut_r[i] = i;
-		cirrus_crtc->lut_g[i] = i;
-		cirrus_crtc->lut_b[i] = i;
-	}
-
 	drm_crtc_helper_add(&cirrus_crtc->base, &cirrus_helper_funcs);
 }
 
-/** Sets the color ramps on behalf of fbcon */
-void cirrus_crtc_fb_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
-			      u16 blue, int regno)
-{
-	struct cirrus_crtc *cirrus_crtc = to_cirrus_crtc(crtc);
-
-	cirrus_crtc->lut_r[regno] = red;
-	cirrus_crtc->lut_g[regno] = green;
-	cirrus_crtc->lut_b[regno] = blue;
-}
-
-/** Gets the color ramps on behalf of fbcon */
-void cirrus_crtc_fb_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
-			      u16 *blue, int regno)
-{
-	struct cirrus_crtc *cirrus_crtc = to_cirrus_crtc(crtc);
-
-	*red = cirrus_crtc->lut_r[regno];
-	*green = cirrus_crtc->lut_g[regno];
-	*blue = cirrus_crtc->lut_b[regno];
-}
-
 static void cirrus_encoder_mode_set(struct drm_encoder *encoder,
 				struct drm_display_mode *mode,
 				struct drm_display_mode *adjusted_mode)
-- 
2.1.4

[PATCH 05/11] dmr: gma500: remove dead code and pointless local lut storage

[Peter Rosin]

The redundant fb helpers .gamma_set and .gamma_get are no longer
used. Remove the dead code and hook up the crtc .gamma_set
to use the crtc gamma_store directly instead of duplicating that
info locally.

It is a bit strange that the fb helper .load_lut was not hooked
up, so this change may well make the driver work for the C8 mode
from the fbdev interface. But that is untested.

Signed-off-by: Peter Rosin <peda@axentia.se>
---
 drivers/gpu/drm/gma500/framebuffer.c       | 22 --------------------
 drivers/gpu/drm/gma500/gma_display.c       | 32 ++++++++++--------------------
 drivers/gpu/drm/gma500/psb_intel_display.c |  7 +------
 drivers/gpu/drm/gma500/psb_intel_drv.h     |  1 -
 4 files changed, 12 insertions(+), 50 deletions(-)

diff --git a/drivers/gpu/drm/gma500/framebuffer.c b/drivers/gpu/drm/gma500/framebuffer.c
index 7da70b6..2570c7f 100644
--- a/drivers/gpu/drm/gma500/framebuffer.c
+++ b/drivers/gpu/drm/gma500/framebuffer.c
@@ -479,26 +479,6 @@ static struct drm_framebuffer *psb_user_framebuffer_create
 	return psb_framebuffer_create(dev, cmd, r);
 }
 
-static void psbfb_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
-							u16 blue, int regno)
-{
-	struct gma_crtc *gma_crtc = to_gma_crtc(crtc);
-
-	gma_crtc->lut_r[regno] = red >> 8;
-	gma_crtc->lut_g[regno] = green >> 8;
-	gma_crtc->lut_b[regno] = blue >> 8;
-}
-
-static void psbfb_gamma_get(struct drm_crtc *crtc, u16 *red,
-					u16 *green, u16 *blue, int regno)
-{
-	struct gma_crtc *gma_crtc = to_gma_crtc(crtc);
-
-	*red = gma_crtc->lut_r[regno] << 8;
-	*green = gma_crtc->lut_g[regno] << 8;
-	*blue = gma_crtc->lut_b[regno] << 8;
-}
-
 static int psbfb_probe(struct drm_fb_helper *helper,
 				struct drm_fb_helper_surface_size *sizes)
 {
@@ -525,8 +505,6 @@ static int psbfb_probe(struct drm_fb_helper *helper,
 }
 
 static const struct drm_fb_helper_funcs psb_fb_helper_funcs = {
-	.gamma_set = psbfb_gamma_set,
-	.gamma_get = psbfb_gamma_get,
 	.fb_probe = psbfb_probe,
 };
 
diff --git a/drivers/gpu/drm/gma500/gma_display.c b/drivers/gpu/drm/gma500/gma_display.c
index e7fd356..f3c48a2 100644
--- a/drivers/gpu/drm/gma500/gma_display.c
+++ b/drivers/gpu/drm/gma500/gma_display.c
@@ -144,33 +144,32 @@ void gma_crtc_load_lut(struct drm_crtc *crtc)
 	struct gma_crtc *gma_crtc = to_gma_crtc(crtc);
 	const struct psb_offset *map = &dev_priv->regmap[gma_crtc->pipe];
 	int palreg = map->palette;
+	u16 *r, *g, *b;
 	int i;
 
 	/* The clocks have to be on to load the palette. */
 	if (!crtc->enabled)
 		return;
 
+	r = crtc->gamma_store;
+	g = r + crtc->gamma_size;
+	b = g + crtc->gamma_size;
+
 	if (gma_power_begin(dev, false)) {
 		for (i = 0; i < 256; i++) {
 			REG_WRITE(palreg + 4 * i,
-				  ((gma_crtc->lut_r[i] +
-				  gma_crtc->lut_adj[i]) << 16) |
-				  ((gma_crtc->lut_g[i] +
-				  gma_crtc->lut_adj[i]) << 8) |
-				  (gma_crtc->lut_b[i] +
-				  gma_crtc->lut_adj[i]));
+				  (((*r++ >> 8) + gma_crtc->lut_adj[i]) << 16) |
+				  (((*g++ >> 8) + gma_crtc->lut_adj[i]) << 8) |
+				  ((*b++ >> 8) + gma_crtc->lut_adj[i]));
 		}
 		gma_power_end(dev);
 	} else {
 		for (i = 0; i < 256; i++) {
 			/* FIXME: Why pipe[0] and not pipe[..._crtc->pipe]? */
 			dev_priv->regs.pipe[0].palette[i] =
-				  ((gma_crtc->lut_r[i] +
-				  gma_crtc->lut_adj[i]) << 16) |
-				  ((gma_crtc->lut_g[i] +
-				  gma_crtc->lut_adj[i]) << 8) |
-				  (gma_crtc->lut_b[i] +
-				  gma_crtc->lut_adj[i]);
+				(((*r++ >> 8) + gma_crtc->lut_adj[i]) << 16) |
+				(((*g++ >> 8) + gma_crtc->lut_adj[i]) << 8) |
+				((*b++ >> 8) + gma_crtc->lut_adj[i]);
 		}
 
 	}
@@ -180,15 +179,6 @@ int gma_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green, u16 *blue,
 		       u32 size,
 		       struct drm_modeset_acquire_ctx *ctx)
 {
-	struct gma_crtc *gma_crtc = to_gma_crtc(crtc);
-	int i;
-
-	for (i = 0; i < size; i++) {
-		gma_crtc->lut_r[i] = red[i] >> 8;
-		gma_crtc->lut_g[i] = green[i] >> 8;
-		gma_crtc->lut_b[i] = blue[i] >> 8;
-	}
-
 	gma_crtc_load_lut(crtc);
 
 	return 0;
diff --git a/drivers/gpu/drm/gma500/psb_intel_display.c b/drivers/gpu/drm/gma500/psb_intel_display.c
index 7b6c849..8762efa 100644
--- a/drivers/gpu/drm/gma500/psb_intel_display.c
+++ b/drivers/gpu/drm/gma500/psb_intel_display.c
@@ -518,13 +518,8 @@ void psb_intel_crtc_init(struct drm_device *dev, int pipe,
 	gma_crtc->pipe = pipe;
 	gma_crtc->plane = pipe;
 
-	for (i = 0; i < 256; i++) {
-		gma_crtc->lut_r[i] = i;
-		gma_crtc->lut_g[i] = i;
-		gma_crtc->lut_b[i] = i;
-
+	for (i = 0; i < 256; i++)
 		gma_crtc->lut_adj[i] = 0;
-	}
 
 	gma_crtc->mode_dev = mode_dev;
 	gma_crtc->cursor_addr = 0;
diff --git a/drivers/gpu/drm/gma500/psb_intel_drv.h b/drivers/gpu/drm/gma500/psb_intel_drv.h
index 6a10215..e8e4ea1 100644
--- a/drivers/gpu/drm/gma500/psb_intel_drv.h
+++ b/drivers/gpu/drm/gma500/psb_intel_drv.h
@@ -172,7 +172,6 @@ struct gma_crtc {
 	int plane;
 	uint32_t cursor_addr;
 	struct gtt_range *cursor_gt;
-	u8 lut_r[256], lut_g[256], lut_b[256];
 	u8 lut_adj[256];
 	struct psb_intel_framebuffer *fbdev_fb;
 	/* a mode_set for fbdev users on this crtc */
-- 
2.1.4

[PATCH 06/11] drm: i915: remove dead code and pointless local lut storage

[Peter Rosin]

The driver stores lut values from the fbdev interface, and is able
to give them back, but does not appear to do anything with these
lut values. The generic fb helpers have replaced this function,
and may even have made the driver work for the C8 mode from the
fbdev interface. But that is untested.

Since the fb helper .gamma_set and .gamma_get are no longer used,
just kill the mysterious dead code.

Signed-off-by: Peter Rosin <peda@axentia.se>
---
 drivers/gpu/drm/i915/intel_drv.h   |  1 -
 drivers/gpu/drm/i915/intel_fbdev.c | 31 -------------------------------
 2 files changed, 32 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 83dd409..503edf3 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -785,7 +785,6 @@ struct intel_crtc {
 	struct drm_crtc base;
 	enum pipe pipe;
 	enum plane plane;
-	u8 lut_r[256], lut_g[256], lut_b[256];
 	/*
 	 * Whether the crtc and the connected output pipeline is active. Implies
 	 * that crtc->enabled is set, i.e. the current mode configuration has
diff --git a/drivers/gpu/drm/i915/intel_fbdev.c b/drivers/gpu/drm/i915/intel_fbdev.c
index 03347c6..5bac953 100644
--- a/drivers/gpu/drm/i915/intel_fbdev.c
+++ b/drivers/gpu/drm/i915/intel_fbdev.c
@@ -281,27 +281,6 @@ static int intelfb_create(struct drm_fb_helper *helper,
 	return ret;
 }
 
-/** Sets the color ramps on behalf of RandR */
-static void intel_crtc_fb_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
-				    u16 blue, int regno)
-{
-	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
-
-	intel_crtc->lut_r[regno] = red >> 8;
-	intel_crtc->lut_g[regno] = green >> 8;
-	intel_crtc->lut_b[regno] = blue >> 8;
-}
-
-static void intel_crtc_fb_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
-				    u16 *blue, int regno)
-{
-	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
-
-	*red = intel_crtc->lut_r[regno] << 8;
-	*green = intel_crtc->lut_g[regno] << 8;
-	*blue = intel_crtc->lut_b[regno] << 8;
-}
-
 static struct drm_fb_helper_crtc *
 intel_fb_helper_crtc(struct drm_fb_helper *fb_helper, struct drm_crtc *crtc)
 {
@@ -370,7 +349,6 @@ static bool intel_fb_initial_config(struct drm_fb_helper *fb_helper,
 		struct drm_connector *connector;
 		struct drm_encoder *encoder;
 		struct drm_fb_helper_crtc *new_crtc;
-		struct intel_crtc *intel_crtc;
 
 		fb_conn = fb_helper->connector_info[i];
 		connector = fb_conn->connector;
@@ -412,13 +390,6 @@ static bool intel_fb_initial_config(struct drm_fb_helper *fb_helper,
 
 		num_connectors_enabled++;
 
-		intel_crtc = to_intel_crtc(connector->state->crtc);
-		for (j = 0; j < 256; j++) {
-			intel_crtc->lut_r[j] = j;
-			intel_crtc->lut_g[j] = j;
-			intel_crtc->lut_b[j] = j;
-		}
-
 		new_crtc = intel_fb_helper_crtc(fb_helper,
 						connector->state->crtc);
 
@@ -519,8 +490,6 @@ static bool intel_fb_initial_config(struct drm_fb_helper *fb_helper,
 
 static const struct drm_fb_helper_funcs intel_fb_helper_funcs = {
 	.initial_config = intel_fb_initial_config,
-	.gamma_set = intel_crtc_fb_gamma_set,
-	.gamma_get = intel_crtc_fb_gamma_get,
 	.fb_probe = intelfb_create,
 };
 
-- 
2.1.4

[PATCH 07/11] drm: mgag200: remove dead code and pointless local lut storage

[Peter Rosin]

The redundant fb helpers .load_lut, .gamma_set and .gamma_get are
no longer used. Remove the dead code and hook up the crtc .gamma_set
to use the crtc gamma_store directly instead of duplicating that
info locally.

Signed-off-by: Peter Rosin <peda@axentia.se>
---
 drivers/gpu/drm/mgag200/mgag200_drv.h  |  5 ---
 drivers/gpu/drm/mgag200/mgag200_fb.c   |  2 --
 drivers/gpu/drm/mgag200/mgag200_mode.c | 62 ++++++++--------------------------
 3 files changed, 15 insertions(+), 54 deletions(-)

diff --git a/drivers/gpu/drm/mgag200/mgag200_drv.h b/drivers/gpu/drm/mgag200/mgag200_drv.h
index c88b6ec..04f1dfb 100644
--- a/drivers/gpu/drm/mgag200/mgag200_drv.h
+++ b/drivers/gpu/drm/mgag200/mgag200_drv.h
@@ -237,11 +237,6 @@ mgag200_bo(struct ttm_buffer_object *bo)
 {
 	return container_of(bo, struct mgag200_bo, bo);
 }
-				/* mgag200_crtc.c */
-void mga_crtc_fb_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
-			     u16 blue, int regno);
-void mga_crtc_fb_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
-			     u16 *blue, int regno);
 
 				/* mgag200_mode.c */
 int mgag200_modeset_init(struct mga_device *mdev);
diff --git a/drivers/gpu/drm/mgag200/mgag200_fb.c b/drivers/gpu/drm/mgag200/mgag200_fb.c
index 5d3b1fa..5cf980a 100644
--- a/drivers/gpu/drm/mgag200/mgag200_fb.c
+++ b/drivers/gpu/drm/mgag200/mgag200_fb.c
@@ -258,8 +258,6 @@ static int mga_fbdev_destroy(struct drm_device *dev,
 }
 
 static const struct drm_fb_helper_funcs mga_fb_helper_funcs = {
-	.gamma_set = mga_crtc_fb_gamma_set,
-	.gamma_get = mga_crtc_fb_gamma_get,
 	.fb_probe = mgag200fb_create,
 };
 
diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
index adb411a..117bec3 100644
--- a/drivers/gpu/drm/mgag200/mgag200_mode.c
+++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
@@ -27,15 +27,19 @@
 
 static void mga_crtc_load_lut(struct drm_crtc *crtc)
 {
-	struct mga_crtc *mga_crtc = to_mga_crtc(crtc);
 	struct drm_device *dev = crtc->dev;
 	struct mga_device *mdev = dev->dev_private;
 	struct drm_framebuffer *fb = crtc->primary->fb;
+	u16 *r_ptr, *g_ptr, *b_ptr;
 	int i;
 
 	if (!crtc->enabled)
 		return;
 
+	r_ptr = crtc->gamma_store;
+	g_ptr = r_ptr + crtc->gamma_size;
+	b_ptr = g_ptr + crtc->gamma_size;
+
 	WREG8(DAC_INDEX + MGA1064_INDEX, 0);
 
 	if (fb && fb->format->cpp[0] * 8 == 16) {
@@ -46,25 +50,27 @@ static void mga_crtc_load_lut(struct drm_crtc *crtc)
 				if (i > (MGAG200_LUT_SIZE >> 1)) {
 					r = b = 0;
 				} else {
-					r = mga_crtc->lut_r[i << 1];
-					b = mga_crtc->lut_b[i << 1];
+					r = *r_ptr++ >> 8;
+					b = *b_ptr++ >> 8;
+					r_ptr++;
+					b_ptr++;
 				}
 			} else {
-				r = mga_crtc->lut_r[i];
-				b = mga_crtc->lut_b[i];
+				r = *r_ptr++ >> 8;
+				b = *b_ptr++ >> 8;
 			}
 			/* VGA registers */
 			WREG8(DAC_INDEX + MGA1064_COL_PAL, r);
-			WREG8(DAC_INDEX + MGA1064_COL_PAL, mga_crtc->lut_g[i]);
+			WREG8(DAC_INDEX + MGA1064_COL_PAL, *g_ptr++ >> 8);
 			WREG8(DAC_INDEX + MGA1064_COL_PAL, b);
 		}
 		return;
 	}
 	for (i = 0; i < MGAG200_LUT_SIZE; i++) {
 		/* VGA registers */
-		WREG8(DAC_INDEX + MGA1064_COL_PAL, mga_crtc->lut_r[i]);
-		WREG8(DAC_INDEX + MGA1064_COL_PAL, mga_crtc->lut_g[i]);
-		WREG8(DAC_INDEX + MGA1064_COL_PAL, mga_crtc->lut_b[i]);
+		WREG8(DAC_INDEX + MGA1064_COL_PAL, *r_ptr++ >> 8);
+		WREG8(DAC_INDEX + MGA1064_COL_PAL, *g_ptr++ >> 8);
+		WREG8(DAC_INDEX + MGA1064_COL_PAL, *b_ptr++ >> 8);
 	}
 }
 
@@ -1396,14 +1402,6 @@ static int mga_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
 			      u16 *blue, uint32_t size,
 			      struct drm_modeset_acquire_ctx *ctx)
 {
-	struct mga_crtc *mga_crtc = to_mga_crtc(crtc);
-	int i;
-
-	for (i = 0; i < size; i++) {
-		mga_crtc->lut_r[i] = red[i] >> 8;
-		mga_crtc->lut_g[i] = green[i] >> 8;
-		mga_crtc->lut_b[i] = blue[i] >> 8;
-	}
 	mga_crtc_load_lut(crtc);
 
 	return 0;
@@ -1452,14 +1450,12 @@ static const struct drm_crtc_helper_funcs mga_helper_funcs = {
 	.mode_set_base = mga_crtc_mode_set_base,
 	.prepare = mga_crtc_prepare,
 	.commit = mga_crtc_commit,
-	.load_lut = mga_crtc_load_lut,
 };
 
 /* CRTC setup */
 static void mga_crtc_init(struct mga_device *mdev)
 {
 	struct mga_crtc *mga_crtc;
-	int i;
 
 	mga_crtc = kzalloc(sizeof(struct mga_crtc) +
 			      (MGAG200FB_CONN_LIMIT * sizeof(struct drm_connector *)),
@@ -1473,37 +1469,9 @@ static void mga_crtc_init(struct mga_device *mdev)
 	drm_mode_crtc_set_gamma_size(&mga_crtc->base, MGAG200_LUT_SIZE);
 	mdev->mode_info.crtc = mga_crtc;
 
-	for (i = 0; i < MGAG200_LUT_SIZE; i++) {
-		mga_crtc->lut_r[i] = i;
-		mga_crtc->lut_g[i] = i;
-		mga_crtc->lut_b[i] = i;
-	}
-
 	drm_crtc_helper_add(&mga_crtc->base, &mga_helper_funcs);
 }
 
-/** Sets the color ramps on behalf of fbcon */
-void mga_crtc_fb_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
-			      u16 blue, int regno)
-{
-	struct mga_crtc *mga_crtc = to_mga_crtc(crtc);
-
-	mga_crtc->lut_r[regno] = red >> 8;
-	mga_crtc->lut_g[regno] = green >> 8;
-	mga_crtc->lut_b[regno] = blue >> 8;
-}
-
-/** Gets the color ramps on behalf of fbcon */
-void mga_crtc_fb_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
-			      u16 *blue, int regno)
-{
-	struct mga_crtc *mga_crtc = to_mga_crtc(crtc);
-
-	*red = (u16)mga_crtc->lut_r[regno] << 8;
-	*green = (u16)mga_crtc->lut_g[regno] << 8;
-	*blue = (u16)mga_crtc->lut_b[regno] << 8;
-}
-
 /*
  * The encoder comes after the CRTC in the output pipeline, but before
  * the connector. It's responsible for ensuring that the digital
-- 
2.1.4

[PATCH 08/11] drm: nouveau: remove dead code and pointless local lut storage

[Peter Rosin]

The redundant fb helpers .load_lut, .gamma_set and .gamma_get are
no longer used. Remove the dead code and hook up the crtc .gamma_set
to use the crtc gamma_store directly instead of duplicating that
info locally.

Signed-off-by: Peter Rosin <peda@axentia.se>
---
 drivers/gpu/drm/nouveau/dispnv04/crtc.c | 26 ++++++++--------------
 drivers/gpu/drm/nouveau/nouveau_crtc.h  |  3 ---
 drivers/gpu/drm/nouveau/nouveau_fbcon.c | 22 -------------------
 drivers/gpu/drm/nouveau/nv50_display.c  | 39 ++++++++++-----------------------
 4 files changed, 21 insertions(+), 69 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/dispnv04/crtc.c b/drivers/gpu/drm/nouveau/dispnv04/crtc.c
index 4b4b0b4..8f689f1 100644
--- a/drivers/gpu/drm/nouveau/dispnv04/crtc.c
+++ b/drivers/gpu/drm/nouveau/dispnv04/crtc.c
@@ -764,13 +764,18 @@ nv_crtc_gamma_load(struct drm_crtc *crtc)
 	struct nouveau_crtc *nv_crtc = nouveau_crtc(crtc);
 	struct drm_device *dev = nv_crtc->base.dev;
 	struct rgb { uint8_t r, g, b; } __attribute__((packed)) *rgbs;
+	u16 *r, *g, *b;
 	int i;
 
 	rgbs = (struct rgb *)nv04_display(dev)->mode_reg.crtc_reg[nv_crtc->index].DAC;
+	r = crtc->gamma_store;
+	g = r + crtc->gamma_size;
+	b = g + crtc->gamma_size;
+
 	for (i = 0; i < 256; i++) {
-		rgbs[i].r = nv_crtc->lut.r[i] >> 8;
-		rgbs[i].g = nv_crtc->lut.g[i] >> 8;
-		rgbs[i].b = nv_crtc->lut.b[i] >> 8;
+		rgbs[i].r = *r++ >> 8;
+		rgbs[i].g = *g++ >> 8;
+		rgbs[i].b = *b++ >> 8;
 	}
 
 	nouveau_hw_load_state_palette(dev, nv_crtc->index, &nv04_display(dev)->mode_reg);
@@ -792,13 +797,6 @@ nv_crtc_gamma_set(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b,
 		  struct drm_modeset_acquire_ctx *ctx)
 {
 	struct nouveau_crtc *nv_crtc = nouveau_crtc(crtc);
-	int i;
-
-	for (i = 0; i < size; i++) {
-		nv_crtc->lut.r[i] = r[i];
-		nv_crtc->lut.g[i] = g[i];
-		nv_crtc->lut.b[i] = b[i];
-	}
 
 	/* We need to know the depth before we upload, but it's possible to
 	 * get called before a framebuffer is bound.  If this is the case,
@@ -1095,7 +1093,6 @@ static const struct drm_crtc_helper_funcs nv04_crtc_helper_funcs = {
 	.mode_set = nv_crtc_mode_set,
 	.mode_set_base = nv04_crtc_mode_set_base,
 	.mode_set_base_atomic = nv04_crtc_mode_set_base_atomic,
-	.load_lut = nv_crtc_gamma_load,
 	.disable = nv_crtc_disable,
 };
 
@@ -1103,17 +1100,12 @@ int
 nv04_crtc_create(struct drm_device *dev, int crtc_num)
 {
 	struct nouveau_crtc *nv_crtc;
-	int ret, i;
+	int ret;
 
 	nv_crtc = kzalloc(sizeof(*nv_crtc), GFP_KERNEL);
 	if (!nv_crtc)
 		return -ENOMEM;
 
-	for (i = 0; i < 256; i++) {
-		nv_crtc->lut.r[i] = i << 8;
-		nv_crtc->lut.g[i] = i << 8;
-		nv_crtc->lut.b[i] = i << 8;
-	}
 	nv_crtc->lut.depth = 0;
 
 	nv_crtc->index = crtc_num;
diff --git a/drivers/gpu/drm/nouveau/nouveau_crtc.h b/drivers/gpu/drm/nouveau/nouveau_crtc.h
index 050fcf3..b7a18fb 100644
--- a/drivers/gpu/drm/nouveau/nouveau_crtc.h
+++ b/drivers/gpu/drm/nouveau/nouveau_crtc.h
@@ -61,9 +61,6 @@ struct nouveau_crtc {
 
 	struct {
 		struct nouveau_bo *nvbo;
-		uint16_t r[256];
-		uint16_t g[256];
-		uint16_t b[256];
 		int depth;
 	} lut;
 
diff --git a/drivers/gpu/drm/nouveau/nouveau_fbcon.c b/drivers/gpu/drm/nouveau/nouveau_fbcon.c
index 2665a07..f770784 100644
--- a/drivers/gpu/drm/nouveau/nouveau_fbcon.c
+++ b/drivers/gpu/drm/nouveau/nouveau_fbcon.c
@@ -278,26 +278,6 @@ nouveau_fbcon_accel_init(struct drm_device *dev)
 		info->fbops = &nouveau_fbcon_ops;
 }
 
-static void nouveau_fbcon_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
-				    u16 blue, int regno)
-{
-	struct nouveau_crtc *nv_crtc = nouveau_crtc(crtc);
-
-	nv_crtc->lut.r[regno] = red;
-	nv_crtc->lut.g[regno] = green;
-	nv_crtc->lut.b[regno] = blue;
-}
-
-static void nouveau_fbcon_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
-				    u16 *blue, int regno)
-{
-	struct nouveau_crtc *nv_crtc = nouveau_crtc(crtc);
-
-	*red = nv_crtc->lut.r[regno];
-	*green = nv_crtc->lut.g[regno];
-	*blue = nv_crtc->lut.b[regno];
-}
-
 static void
 nouveau_fbcon_zfill(struct drm_device *dev, struct nouveau_fbdev *fbcon)
 {
@@ -467,8 +447,6 @@ void nouveau_fbcon_gpu_lockup(struct fb_info *info)
 }
 
 static const struct drm_fb_helper_funcs nouveau_fbcon_helper_funcs = {
-	.gamma_set = nouveau_fbcon_gamma_set,
-	.gamma_get = nouveau_fbcon_gamma_get,
 	.fb_probe = nouveau_fbcon_create,
 };
 
diff --git a/drivers/gpu/drm/nouveau/nv50_display.c b/drivers/gpu/drm/nouveau/nv50_display.c
index 775c100..3686f5b 100644
--- a/drivers/gpu/drm/nouveau/nv50_display.c
+++ b/drivers/gpu/drm/nouveau/nv50_display.c
@@ -2193,28 +2193,28 @@ nv50_head_lut_load(struct drm_crtc *crtc)
 	struct nv50_disp *disp = nv50_disp(crtc->dev);
 	struct nouveau_crtc *nv_crtc = nouveau_crtc(crtc);
 	void __iomem *lut = nvbo_kmap_obj_iovirtual(nv_crtc->lut.nvbo);
+	u16 *r, *g, *b;
 	int i;
 
-	for (i = 0; i < 256; i++) {
-		u16 r = nv_crtc->lut.r[i] >> 2;
-		u16 g = nv_crtc->lut.g[i] >> 2;
-		u16 b = nv_crtc->lut.b[i] >> 2;
+	r = crtc->gamma_store;
+	g = r + crtc->gamma_size;
+	b = g + crtc->gamma_size;
 
+	for (i = 0; i < 256; i++) {
 		if (disp->disp->oclass < GF110_DISP) {
-			writew(r + 0x0000, lut + (i * 0x08) + 0);
-			writew(g + 0x0000, lut + (i * 0x08) + 2);
-			writew(b + 0x0000, lut + (i * 0x08) + 4);
+			writew((*r++ >> 2) + 0x0000, lut + (i * 0x08) + 0);
+			writew((*g++ >> 2) + 0x0000, lut + (i * 0x08) + 2);
+			writew((*b++ >> 2) + 0x0000, lut + (i * 0x08) + 4);
 		} else {
-			writew(r + 0x6000, lut + (i * 0x20) + 0);
-			writew(g + 0x6000, lut + (i * 0x20) + 2);
-			writew(b + 0x6000, lut + (i * 0x20) + 4);
+			writew((*r++ >> 2) + 0x6000, lut + (i * 0x20) + 0);
+			writew((*g++ >> 2) + 0x6000, lut + (i * 0x20) + 2);
+			writew((*b++ >> 2) + 0x6000, lut + (i * 0x20) + 4);
 		}
 	}
 }
 
 static const struct drm_crtc_helper_funcs
 nv50_head_help = {
-	.load_lut = nv50_head_lut_load,
 	.atomic_check = nv50_head_atomic_check,
 };
 
@@ -2223,15 +2223,6 @@ nv50_head_gamma_set(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b,
 		    uint32_t size,
 		    struct drm_modeset_acquire_ctx *ctx)
 {
-	struct nouveau_crtc *nv_crtc = nouveau_crtc(crtc);
-	u32 i;
-
-	for (i = 0; i < size; i++) {
-		nv_crtc->lut.r[i] = r[i];
-		nv_crtc->lut.g[i] = g[i];
-		nv_crtc->lut.b[i] = b[i];
-	}
-
 	nv50_head_lut_load(crtc);
 	return 0;
 }
@@ -2329,19 +2320,13 @@ nv50_head_create(struct drm_device *dev, int index)
 	struct nv50_base *base;
 	struct nv50_curs *curs;
 	struct drm_crtc *crtc;
-	int ret, i;
+	int ret;
 
 	head = kzalloc(sizeof(*head), GFP_KERNEL);
 	if (!head)
 		return -ENOMEM;
 
 	head->base.index = index;
-	for (i = 0; i < 256; i++) {
-		head->base.lut.r[i] = i << 8;
-		head->base.lut.g[i] = i << 8;
-		head->base.lut.b[i] = i << 8;
-	}
-
 	ret = nv50_base_new(drm, head, &base);
 	if (ret == 0)
 		ret = nv50_curs_new(drm, head, &curs);
-- 
2.1.4

[PATCH 09/11] drm: radeon: remove dead code and pointless local lut storage

[Peter Rosin]

The redundant fb helpers .load_lut, .gamma_set and .gamma_get are
no longer used. Remove the dead code and hook up the crtc .gamma_set
to use the crtc gamma_store directly instead of duplicating that
info locally.

Signed-off-by: Peter Rosin <peda@axentia.se>
---
 drivers/gpu/drm/radeon/atombios_crtc.c      |  1 -
 drivers/gpu/drm/radeon/radeon_connectors.c  |  7 ++-
 drivers/gpu/drm/radeon/radeon_display.c     | 71 ++++++++++++-----------------
 drivers/gpu/drm/radeon/radeon_fb.c          |  2 -
 drivers/gpu/drm/radeon/radeon_legacy_crtc.c |  1 -
 5 files changed, 33 insertions(+), 49 deletions(-)

diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c b/drivers/gpu/drm/radeon/atombios_crtc.c
index 3c492a0..02baaaf 100644
--- a/drivers/gpu/drm/radeon/atombios_crtc.c
+++ b/drivers/gpu/drm/radeon/atombios_crtc.c
@@ -2217,7 +2217,6 @@ static const struct drm_crtc_helper_funcs atombios_helper_funcs = {
 	.mode_set_base_atomic = atombios_crtc_set_base_atomic,
 	.prepare = atombios_crtc_prepare,
 	.commit = atombios_crtc_commit,
-	.load_lut = radeon_crtc_load_lut,
 	.disable = atombios_crtc_disable,
 };
 
diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c b/drivers/gpu/drm/radeon/radeon_connectors.c
index 27affbd..2f642cb 100644
--- a/drivers/gpu/drm/radeon/radeon_connectors.c
+++ b/drivers/gpu/drm/radeon/radeon_connectors.c
@@ -773,12 +773,15 @@ static int radeon_connector_set_property(struct drm_connector *connector, struct
 
 		if (connector->encoder->crtc) {
 			struct drm_crtc *crtc  = connector->encoder->crtc;
-			const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 			struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
 
 			radeon_crtc->output_csc = radeon_encoder->output_csc;
 
-			(*crtc_funcs->load_lut)(crtc);
+			/*
+			 * Our .gamma_set assumes the .gamma_store has been
+			 * prefilled and don't care about its arguments.
+			 */
+			crtc->funcs->gamma_set(crtc, NULL, NULL, NULL, 0, NULL);
 		}
 	}
 
diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c
index 17d3daf..8b7d7a0 100644
--- a/drivers/gpu/drm/radeon/radeon_display.c
+++ b/drivers/gpu/drm/radeon/radeon_display.c
@@ -42,6 +42,7 @@ static void avivo_crtc_load_lut(struct drm_crtc *crtc)
 	struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
 	struct drm_device *dev = crtc->dev;
 	struct radeon_device *rdev = dev->dev_private;
+	u16 *r, *g, *b;
 	int i;
 
 	DRM_DEBUG_KMS("%d\n", radeon_crtc->crtc_id);
@@ -60,11 +61,14 @@ static void avivo_crtc_load_lut(struct drm_crtc *crtc)
 	WREG32(AVIVO_DC_LUT_WRITE_EN_MASK, 0x0000003f);
 
 	WREG8(AVIVO_DC_LUT_RW_INDEX, 0);
+	r = crtc->gamma_store;
+	g = r + crtc->gamma_size;
+	b = g + crtc->gamma_size;
 	for (i = 0; i < 256; i++) {
 		WREG32(AVIVO_DC_LUT_30_COLOR,
-			     (radeon_crtc->lut_r[i] << 20) |
-			     (radeon_crtc->lut_g[i] << 10) |
-			     (radeon_crtc->lut_b[i] << 0));
+		       ((*r++ & 0xffc0) << 14) |
+		       ((*g++ & 0xffc0) << 4) |
+		       (*b++ >> 6));
 	}
 
 	/* Only change bit 0 of LUT_SEL, other bits are set elsewhere */
@@ -76,6 +80,7 @@ static void dce4_crtc_load_lut(struct drm_crtc *crtc)
 	struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
 	struct drm_device *dev = crtc->dev;
 	struct radeon_device *rdev = dev->dev_private;
+	u16 *r, *g, *b;
 	int i;
 
 	DRM_DEBUG_KMS("%d\n", radeon_crtc->crtc_id);
@@ -93,11 +98,14 @@ static void dce4_crtc_load_lut(struct drm_crtc *crtc)
 	WREG32(EVERGREEN_DC_LUT_WRITE_EN_MASK + radeon_crtc->crtc_offset, 0x00000007);
 
 	WREG32(EVERGREEN_DC_LUT_RW_INDEX + radeon_crtc->crtc_offset, 0);
+	r = crtc->gamma_store;
+	g = r + crtc->gamma_size;
+	b = g + crtc->gamma_size;
 	for (i = 0; i < 256; i++) {
 		WREG32(EVERGREEN_DC_LUT_30_COLOR + radeon_crtc->crtc_offset,
-		       (radeon_crtc->lut_r[i] << 20) |
-		       (radeon_crtc->lut_g[i] << 10) |
-		       (radeon_crtc->lut_b[i] << 0));
+		       ((*r++ & 0xffc0) << 14) |
+		       ((*g++ & 0xffc0) << 4) |
+		       (*b++ >> 6));
 	}
 }
 
@@ -106,6 +114,7 @@ static void dce5_crtc_load_lut(struct drm_crtc *crtc)
 	struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
 	struct drm_device *dev = crtc->dev;
 	struct radeon_device *rdev = dev->dev_private;
+	u16 *r, *g, *b;
 	int i;
 
 	DRM_DEBUG_KMS("%d\n", radeon_crtc->crtc_id);
@@ -135,11 +144,14 @@ static void dce5_crtc_load_lut(struct drm_crtc *crtc)
 	WREG32(EVERGREEN_DC_LUT_WRITE_EN_MASK + radeon_crtc->crtc_offset, 0x00000007);
 
 	WREG32(EVERGREEN_DC_LUT_RW_INDEX + radeon_crtc->crtc_offset, 0);
+	r = crtc->gamma_store;
+	g = r + crtc->gamma_size;
+	b = g + crtc->gamma_size;
 	for (i = 0; i < 256; i++) {
 		WREG32(EVERGREEN_DC_LUT_30_COLOR + radeon_crtc->crtc_offset,
-		       (radeon_crtc->lut_r[i] << 20) |
-		       (radeon_crtc->lut_g[i] << 10) |
-		       (radeon_crtc->lut_b[i] << 0));
+		       ((*r++ & 0xffc0) << 14) |
+		       ((*g++ & 0xffc0) << 4) |
+		       (*b++ >> 6));
 	}
 
 	WREG32(NI_DEGAMMA_CONTROL + radeon_crtc->crtc_offset,
@@ -172,6 +184,7 @@ static void legacy_crtc_load_lut(struct drm_crtc *crtc)
 	struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
 	struct drm_device *dev = crtc->dev;
 	struct radeon_device *rdev = dev->dev_private;
+	u16 *r, *g, *b;
 	int i;
 	uint32_t dac2_cntl;
 
@@ -183,11 +196,14 @@ static void legacy_crtc_load_lut(struct drm_crtc *crtc)
 	WREG32(RADEON_DAC_CNTL2, dac2_cntl);
 
 	WREG8(RADEON_PALETTE_INDEX, 0);
+	r = crtc->gamma_store;
+	g = r + crtc->gamma_size;
+	b = g + crtc->gamma_size;
 	for (i = 0; i < 256; i++) {
 		WREG32(RADEON_PALETTE_30_DATA,
-			     (radeon_crtc->lut_r[i] << 20) |
-			     (radeon_crtc->lut_g[i] << 10) |
-			     (radeon_crtc->lut_b[i] << 0));
+		       ((*r++ & 0xffc0) << 14) |
+		       ((*g++ & 0xffc0) << 4) |
+		       (*b++ >> 6));
 	}
 }
 
@@ -209,41 +225,10 @@ void radeon_crtc_load_lut(struct drm_crtc *crtc)
 		legacy_crtc_load_lut(crtc);
 }
 
-/** Sets the color ramps on behalf of fbcon */
-void radeon_crtc_fb_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
-			      u16 blue, int regno)
-{
-	struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
-
-	radeon_crtc->lut_r[regno] = red >> 6;
-	radeon_crtc->lut_g[regno] = green >> 6;
-	radeon_crtc->lut_b[regno] = blue >> 6;
-}
-
-/** Gets the color ramps on behalf of fbcon */
-void radeon_crtc_fb_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
-			      u16 *blue, int regno)
-{
-	struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
-
-	*red = radeon_crtc->lut_r[regno] << 6;
-	*green = radeon_crtc->lut_g[regno] << 6;
-	*blue = radeon_crtc->lut_b[regno] << 6;
-}
-
 static int radeon_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
 				 u16 *blue, uint32_t size,
 				 struct drm_modeset_acquire_ctx *ctx)
 {
-	struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
-	int i;
-
-	/* userspace palettes are always correct as is */
-	for (i = 0; i < size; i++) {
-		radeon_crtc->lut_r[i] = red[i] >> 6;
-		radeon_crtc->lut_g[i] = green[i] >> 6;
-		radeon_crtc->lut_b[i] = blue[i] >> 6;
-	}
 	radeon_crtc_load_lut(crtc);
 
 	return 0;
diff --git a/drivers/gpu/drm/radeon/radeon_fb.c b/drivers/gpu/drm/radeon/radeon_fb.c
index 356ad90..638bcb55 100644
--- a/drivers/gpu/drm/radeon/radeon_fb.c
+++ b/drivers/gpu/drm/radeon/radeon_fb.c
@@ -332,8 +332,6 @@ static int radeon_fbdev_destroy(struct drm_device *dev, struct radeon_fbdev *rfb
 }
 
 static const struct drm_fb_helper_funcs radeon_fb_helper_funcs = {
-	.gamma_set = radeon_crtc_fb_gamma_set,
-	.gamma_get = radeon_crtc_fb_gamma_get,
 	.fb_probe = radeonfb_create,
 };
 
diff --git a/drivers/gpu/drm/radeon/radeon_legacy_crtc.c b/drivers/gpu/drm/radeon/radeon_legacy_crtc.c
index ce6cb66..1f1856e 100644
--- a/drivers/gpu/drm/radeon/radeon_legacy_crtc.c
+++ b/drivers/gpu/drm/radeon/radeon_legacy_crtc.c
@@ -1116,7 +1116,6 @@ static const struct drm_crtc_helper_funcs legacy_helper_funcs = {
 	.mode_set_base_atomic = radeon_crtc_set_base_atomic,
 	.prepare = radeon_crtc_prepare,
 	.commit = radeon_crtc_commit,
-	.load_lut = radeon_crtc_load_lut,
 	.disable = radeon_crtc_disable
 };
 
-- 
2.1.4

[PATCH 10/11] drm: stm: remove dead code and pointless local lut storage

[Peter Rosin]

The redundant fb helper .load_lut is no longer used, and can not
work right without also providing the fb helpers .gamma_set and
.gamma_get thus rendering the code in this driver suspect.

Just remove the dead code.

Signed-off-by: Peter Rosin <peda@axentia.se>
---
 drivers/gpu/drm/stm/ltdc.c | 12 ------------
 drivers/gpu/drm/stm/ltdc.h |  1 -
 2 files changed, 13 deletions(-)

diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
index 1b9483d..87829b9 100644
--- a/drivers/gpu/drm/stm/ltdc.c
+++ b/drivers/gpu/drm/stm/ltdc.c
@@ -375,17 +375,6 @@ static irqreturn_t ltdc_irq(int irq, void *arg)
  * DRM_CRTC
  */
 
-static void ltdc_crtc_load_lut(struct drm_crtc *crtc)
-{
-	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
-	unsigned int i, lay;
-
-	for (lay = 0; lay < ldev->caps.nb_layers; lay++)
-		for (i = 0; i < 256; i++)
-			reg_write(ldev->regs, LTDC_L1CLUTWR + lay * LAY_OFS,
-				  ldev->clut[i]);
-}
-
 static void ltdc_crtc_enable(struct drm_crtc *crtc)
 {
 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
@@ -523,7 +512,6 @@ static void ltdc_crtc_atomic_flush(struct drm_crtc *crtc,
 }
 
 static struct drm_crtc_helper_funcs ltdc_crtc_helper_funcs = {
-	.load_lut = ltdc_crtc_load_lut,
 	.enable = ltdc_crtc_enable,
 	.disable = ltdc_crtc_disable,
 	.mode_set_nofb = ltdc_crtc_mode_set_nofb,
diff --git a/drivers/gpu/drm/stm/ltdc.h b/drivers/gpu/drm/stm/ltdc.h
index d7a9c73..620ca55 100644
--- a/drivers/gpu/drm/stm/ltdc.h
+++ b/drivers/gpu/drm/stm/ltdc.h
@@ -27,7 +27,6 @@ struct ltdc_device {
 	struct drm_panel *panel;
 	struct mutex err_lock;	/* protecting error_status */
 	struct ltdc_caps caps;
-	u32 clut[256];		/* color look up table */
 	u32 error_status;
 	u32 irq_status;
 };
-- 
2.1.4

[PATCH 11/11] drm: remove unused and redundant callbacks

[Peter Rosin]

Drivers no longer have any need for these callbacks, and there are no
users. Zap. Zap-zap-zzzap-p-pp-p.

Signed-off-by: Peter Rosin <peda@axentia.se>
---
 include/drm/drm_fb_helper.h              | 32 --------------------------------
 include/drm/drm_modeset_helper_vtables.h | 16 ----------------
 2 files changed, 48 deletions(-)

diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h
index 119e5e4..80d9853 100644
--- a/include/drm/drm_fb_helper.h
+++ b/include/drm/drm_fb_helper.h
@@ -85,38 +85,6 @@ struct drm_fb_helper_surface_size {
  */
 struct drm_fb_helper_funcs {
 	/**
-	 * @gamma_set:
-	 *
-	 * Set the given gamma LUT register on the given CRTC.
-	 *
-	 * This callback is optional.
-	 *
-	 * FIXME:
-	 *
-	 * This callback is functionally redundant with the core gamma table
-	 * support and simply exists because the fbdev hasn't yet been
-	 * refactored to use the core gamma table interfaces.
-	 */
-	void (*gamma_set)(struct drm_crtc *crtc, u16 red, u16 green,
-			  u16 blue, int regno);
-	/**
-	 * @gamma_get:
-	 *
-	 * Read the given gamma LUT register on the given CRTC, used to save the
-	 * current LUT when force-restoring the fbdev for e.g. kdbg.
-	 *
-	 * This callback is optional.
-	 *
-	 * FIXME:
-	 *
-	 * This callback is functionally redundant with the core gamma table
-	 * support and simply exists because the fbdev hasn't yet been
-	 * refactored to use the core gamma table interfaces.
-	 */
-	void (*gamma_get)(struct drm_crtc *crtc, u16 *red, u16 *green,
-			  u16 *blue, int regno);
-
-	/**
 	 * @fb_probe:
 	 *
 	 * Driver callback to allocate and initialize the fbdev info structure.
diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h
index 85984b2..0773db9 100644
--- a/include/drm/drm_modeset_helper_vtables.h
+++ b/include/drm/drm_modeset_helper_vtables.h
@@ -267,22 +267,6 @@ struct drm_crtc_helper_funcs {
 				    enum mode_set_atomic);
 
 	/**
-	 * @load_lut:
-	 *
-	 * Load a LUT prepared with the &drm_fb_helper_funcs.gamma_set vfunc.
-	 *
-	 * This callback is optional and is only used by the fbdev emulation
-	 * helpers.
-	 *
-	 * FIXME:
-	 *
-	 * This callback is functionally redundant with the core gamma table
-	 * support and simply exists because the fbdev hasn't yet been
-	 * refactored to use the core gamma table interfaces.
-	 */
-	void (*load_lut)(struct drm_crtc *crtc);
-
-	/**
 	 * @disable:
 	 *
 	 * This callback should be used to disable the CRTC. With the atomic
-- 
2.1.4

Re: [PATCH 01/11] drm/fb-helper: do a generic fb_setcmap helper in terms of crtc .gamma_set

[Daniel Vetter]

On Tue, Jun 20, 2017 at 09:25:25PM +0200, Peter Rosin wrote:
> This makes the redundant fb helpers .load_lut, .gamma_set and .gamma_get
> totally obsolete.
> 
> I think the gamma_store can end up invalid on error. But the way I read
> it, that can happen in drm_mode_gamma_set_ioctl as well, so why should
> this pesky legacy fbdev stuff be any better?
> 
> drm_fb_helper_save_lut_atomic justs saves the gamma lut for later. However,
> it saves it to the gamma_store which should already be up to date with what
> .gamma_get would return and is thus a nop. So, zap it.

Removing drm_fb_helper_save_lut_atomic should be a separate patch I
think.
 
> Signed-off-by: Peter Rosin <peda@axentia.se>

> ---
>  drivers/gpu/drm/drm_fb_helper.c | 131 ++++++++++++----------------------------
>  1 file changed, 40 insertions(+), 91 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
> index 574af01..cc2d55d 100644
> --- a/drivers/gpu/drm/drm_fb_helper.c
> +++ b/drivers/gpu/drm/drm_fb_helper.c
> @@ -229,22 +229,6 @@ int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
>  }
>  EXPORT_SYMBOL(drm_fb_helper_remove_one_connector);
>  
> -static void drm_fb_helper_save_lut_atomic(struct drm_crtc *crtc, struct drm_fb_helper *helper)
> -{
> -	uint16_t *r_base, *g_base, *b_base;
> -	int i;
> -
> -	if (helper->funcs->gamma_get == NULL)
> -		return;
> -
> -	r_base = crtc->gamma_store;
> -	g_base = r_base + crtc->gamma_size;
> -	b_base = g_base + crtc->gamma_size;
> -
> -	for (i = 0; i < crtc->gamma_size; i++)
> -		helper->funcs->gamma_get(crtc, &r_base[i], &g_base[i], &b_base[i], i);
> -}
> -
>  static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc)
>  {
>  	uint16_t *r_base, *g_base, *b_base;
> @@ -285,7 +269,6 @@ int drm_fb_helper_debug_enter(struct fb_info *info)
>  			if (drm_drv_uses_atomic_modeset(mode_set->crtc->dev))
>  				continue;
>  
> -			drm_fb_helper_save_lut_atomic(mode_set->crtc, helper);
>  			funcs->mode_set_base_atomic(mode_set->crtc,
>  						    mode_set->fb,
>  						    mode_set->x,
> @@ -1167,50 +1150,6 @@ void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
>  }
>  EXPORT_SYMBOL(drm_fb_helper_set_suspend_unlocked);
>  
> -static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green,
> -		     u16 blue, u16 regno, struct fb_info *info)
> -{
> -	struct drm_fb_helper *fb_helper = info->par;
> -	struct drm_framebuffer *fb = fb_helper->fb;
> -
> -	if (info->fix.visual == FB_VISUAL_TRUECOLOR) {

This case here seems gone, and it was also the pièce de résistance when I
tried tackling fbdev lut support. As far as I understand this stuff we do
not support FB_VISUAL_TRUECOLOR palette, and all that bitshifting here is
pointless. But I'm honestly not really clear.

I think removing this case should also be a separate patch, and I'd very
much prefer that someone with some fbdev-clue would ack it.

> -		u32 *palette;
> -		u32 value;
> -		/* place color in psuedopalette */
> -		if (regno > 16)
> -			return -EINVAL;
> -		palette = (u32 *)info->pseudo_palette;
> -		red >>= (16 - info->var.red.length);
> -		green >>= (16 - info->var.green.length);
> -		blue >>= (16 - info->var.blue.length);
> -		value = (red << info->var.red.offset) |
> -			(green << info->var.green.offset) |
> -			(blue << info->var.blue.offset);
> -		if (info->var.transp.length > 0) {
> -			u32 mask = (1 << info->var.transp.length) - 1;
> -
> -			mask <<= info->var.transp.offset;
> -			value |= mask;
> -		}
> -		palette[regno] = value;
> -		return 0;
> -	}
> -
> -	/*
> -	 * The driver really shouldn't advertise pseudo/directcolor
> -	 * visuals if it can't deal with the palette.
> -	 */
> -	if (WARN_ON(!fb_helper->funcs->gamma_set ||
> -		    !fb_helper->funcs->gamma_get))
> -		return -EINVAL;
> -
> -	WARN_ON(fb->format->cpp[0] != 1);
> -
> -	fb_helper->funcs->gamma_set(crtc, red, green, blue, regno);
> -
> -	return 0;
> -}
> -
>  /**
>   * drm_fb_helper_setcmap - implementation for &fb_ops.fb_setcmap
>   * @cmap: cmap to set
> @@ -1220,51 +1159,61 @@ int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
>  {
>  	struct drm_fb_helper *fb_helper = info->par;
>  	struct drm_device *dev = fb_helper->dev;
> -	const struct drm_crtc_helper_funcs *crtc_funcs;
> -	u16 *red, *green, *blue, *transp;
> +	struct drm_modeset_acquire_ctx ctx;
>  	struct drm_crtc *crtc;
> -	int i, j, rc = 0;
> -	int start;
> +	u16 *r, *g, *b;
> +	int i, ret;
>  
>  	if (oops_in_progress)
>  		return -EBUSY;
>  
> -	drm_modeset_lock_all(dev);
> +	if (cmap->start + cmap->len < cmap->start)
> +		return -EINVAL;
> +
> +	drm_modeset_acquire_init(&ctx, 0);
> +retry:
> +	ret = drm_modeset_lock_all_ctx(dev, &ctx);
> +	if (ret)
> +		goto out;
>  	if (!drm_fb_helper_is_bound(fb_helper)) {
> -		drm_modeset_unlock_all(dev);
> -		return -EBUSY;
> +		ret = -EBUSY;
> +		goto out;
>  	}
>  
>  	for (i = 0; i < fb_helper->crtc_count; i++) {
>  		crtc = fb_helper->crtc_info[i].mode_set.crtc;
> -		crtc_funcs = crtc->helper_private;
> -
> -		red = cmap->red;
> -		green = cmap->green;
> -		blue = cmap->blue;
> -		transp = cmap->transp;
> -		start = cmap->start;
> +		if (!crtc->funcs->gamma_set || !crtc->gamma_size) {
> +			ret = -EINVAL;
> +			goto out;
> +		}
>  
> -		for (j = 0; j < cmap->len; j++) {
> -			u16 hred, hgreen, hblue, htransp = 0xffff;
> +		if (cmap->start + cmap->len > crtc->gamma_size) {
> +			ret = -EINVAL;
> +			goto out;
> +		}
>  
> -			hred = *red++;
> -			hgreen = *green++;
> -			hblue = *blue++;
> +		r = crtc->gamma_store;
> +		g = r + crtc->gamma_size;
> +		b = g + crtc->gamma_size;
>  
> -			if (transp)
> -				htransp = *transp++;
> +		memcpy(r + cmap->start, cmap->red, cmap->len * sizeof(u16));
> +		memcpy(g + cmap->start, cmap->green, cmap->len * sizeof(u16));
> +		memcpy(b + cmap->start, cmap->blue, cmap->len * sizeof(u16));
>  
> -			rc = setcolreg(crtc, hred, hgreen, hblue, start++, info);
> -			if (rc)
> -				goto out;
> -		}
> -		if (crtc_funcs->load_lut)
> -			crtc_funcs->load_lut(crtc);
> +		ret = crtc->funcs->gamma_set(crtc, r, g, b,
> +					     crtc->gamma_size, &ctx);
> +		if (ret)
> +			break;
>  	}
> - out:
> -	drm_modeset_unlock_all(dev);
> -	return rc;
> +out:
> +	if (ret == -EDEADLK) {
> +		drm_modeset_backoff(&ctx);
> +		goto retry;
> +	}
> +	drm_modeset_drop_locks(&ctx);
> +	drm_modeset_acquire_fini(&ctx);
> +
> +	return ret;

It's a pre-existing bug, but should we also try to restore the fbdev lut
in drm_fb_helper_restore_fbdev_mode_unlocked()? Would be yet another bug,
but might be relevant for your use-case. Just try to run both an fbdev
application and some kms-native thing, and then SIGKILL the native kms
app.

But since pre-existing not really required, and probably too much effort.

Thanks, Daniel

>  }
>  EXPORT_SYMBOL(drm_fb_helper_setcmap);
>  
> -- 
> 2.1.4
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

Re: [PATCH 00/11] improve the fb_setcmap helper

[Daniel Vetter]

On Tue, Jun 20, 2017 at 09:25:24PM +0200, Peter Rosin wrote:
> Hi!
> 
> While trying to get CLUT support for the atmel_hlcdc driver, and
> specifically for the emulated fbdev interface, I received some
> push-back that my feeble in-driver attempts should be solved
> by the core. This is my attempt to do it right.
> 
> Boris and Daniel, was this approximately what you had in mind?

Yeah, this is awesome. I tried to do it a few times myself, but always
failed (also due to lack of real use-case on my side).

> I have obviously not tested all of this with more than a compile,
> but the first patch is enough to make the atmel-hlcdc driver
> do what I need. The rest is just lots of removals and cleanup
> made possible by the improved core.

If it works for you it's imo good enough. Not sure anyone else really
cares about fbdev lut support at all. I have a few comments on the first
patch, but once that's sorted, and once we have given driver maintainers
enough time to ack I think I'll merge the entire pile into drm-misc.

Nice work, thanks for doing it.

Cheers, Daniel

> Please test, I would not be surprised if I have fouled up some
> bit-manipulation somewhere in this mostly mechanical change...
> 
> Cheers,
> peda
> 
> Peter Rosin (11):
>   drm/fb-helper: do a generic fb_setcmap helper in terms of crtc
>     .gamma_set
>   drm: amd: remove dead code and pointless local lut storage
>   drm: ast: remove dead code and pointless local lut storage
>   drm: cirrus: remove dead code and pointless local lut storage
>   dmr: gma500: remove dead code and pointless local lut storage
>   drm: i915: remove dead code and pointless local lut storage
>   drm: mgag200: remove dead code and pointless local lut storage
>   drm: nouveau: remove dead code and pointless local lut storage
>   drm: radeon: remove dead code and pointless local lut storage
>   drm: stm: remove dead code and pointless local lut storage
>   drm: remove unused and redundant callbacks
> 
>  drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c      |  24 -----
>  drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h    |   1 -
>  drivers/gpu/drm/amd/amdgpu/dce_v10_0.c      |  27 ++----
>  drivers/gpu/drm/amd/amdgpu/dce_v11_0.c      |  27 ++----
>  drivers/gpu/drm/amd/amdgpu/dce_v6_0.c       |  27 ++----
>  drivers/gpu/drm/amd/amdgpu/dce_v8_0.c       |  27 ++----
>  drivers/gpu/drm/amd/amdgpu/dce_virtual.c    |  23 -----
>  drivers/gpu/drm/ast/ast_drv.h               |   1 -
>  drivers/gpu/drm/ast/ast_fb.c                |  20 -----
>  drivers/gpu/drm/ast/ast_mode.c              |  26 ++----
>  drivers/gpu/drm/cirrus/cirrus_drv.h         |   8 --
>  drivers/gpu/drm/cirrus/cirrus_fbdev.c       |   2 -
>  drivers/gpu/drm/cirrus/cirrus_mode.c        |  71 ++++-----------
>  drivers/gpu/drm/drm_fb_helper.c             | 131 +++++++++-------------------
>  drivers/gpu/drm/gma500/framebuffer.c        |  22 -----
>  drivers/gpu/drm/gma500/gma_display.c        |  32 +++----
>  drivers/gpu/drm/gma500/psb_intel_display.c  |   7 +-
>  drivers/gpu/drm/gma500/psb_intel_drv.h      |   1 -
>  drivers/gpu/drm/i915/intel_drv.h            |   1 -
>  drivers/gpu/drm/i915/intel_fbdev.c          |  31 -------
>  drivers/gpu/drm/mgag200/mgag200_drv.h       |   5 --
>  drivers/gpu/drm/mgag200/mgag200_fb.c        |   2 -
>  drivers/gpu/drm/mgag200/mgag200_mode.c      |  62 ++++---------
>  drivers/gpu/drm/nouveau/dispnv04/crtc.c     |  26 ++----
>  drivers/gpu/drm/nouveau/nouveau_crtc.h      |   3 -
>  drivers/gpu/drm/nouveau/nouveau_fbcon.c     |  22 -----
>  drivers/gpu/drm/nouveau/nv50_display.c      |  39 +++------
>  drivers/gpu/drm/radeon/atombios_crtc.c      |   1 -
>  drivers/gpu/drm/radeon/radeon_connectors.c  |   7 +-
>  drivers/gpu/drm/radeon/radeon_display.c     |  71 ++++++---------
>  drivers/gpu/drm/radeon/radeon_fb.c          |   2 -
>  drivers/gpu/drm/radeon/radeon_legacy_crtc.c |   1 -
>  drivers/gpu/drm/stm/ltdc.c                  |  12 ---
>  drivers/gpu/drm/stm/ltdc.h                  |   1 -
>  include/drm/drm_fb_helper.h                 |  32 -------
>  include/drm/drm_modeset_helper_vtables.h    |  16 ----
>  36 files changed, 171 insertions(+), 640 deletions(-)
> 
> -- 
> 2.1.4
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

Re: [PATCH 01/11] drm/fb-helper: do a generic fb_setcmap helper in terms of crtc .gamma_set

[Michel Dänzer]

On 21/06/17 04:38 PM, Daniel Vetter wrote:
> On Tue, Jun 20, 2017 at 09:25:25PM +0200, Peter Rosin wrote:
>> This makes the redundant fb helpers .load_lut, .gamma_set and .gamma_get
>> totally obsolete.
>>
>> I think the gamma_store can end up invalid on error. But the way I read
>> it, that can happen in drm_mode_gamma_set_ioctl as well, so why should
>> this pesky legacy fbdev stuff be any better?
>>
>> drm_fb_helper_save_lut_atomic justs saves the gamma lut for later. However,
>> it saves it to the gamma_store which should already be up to date with what
>> .gamma_get would return and is thus a nop. So, zap it.
> 
> Removing drm_fb_helper_save_lut_atomic should be a separate patch I
> think.
>  
>> Signed-off-by: Peter Rosin <peda@axentia.se>

[...]

>> @@ -1167,50 +1150,6 @@ void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
>>  }
>>  EXPORT_SYMBOL(drm_fb_helper_set_suspend_unlocked);
>>  
>> -static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green,
>> -		     u16 blue, u16 regno, struct fb_info *info)
>> -{
>> -	struct drm_fb_helper *fb_helper = info->par;
>> -	struct drm_framebuffer *fb = fb_helper->fb;
>> -
>> -	if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
> 
> This case here seems gone, and it was also the pièce de résistance when I
> tried tackling fbdev lut support. As far as I understand this stuff we do
> not support FB_VISUAL_TRUECOLOR palette, and all that bitshifting here is
> pointless. But I'm honestly not really clear.
> 
> I think removing this case should also be a separate patch, and I'd very
> much prefer that someone with some fbdev-clue would ack it.

No need for anyone with fbdev-clue, just run fbset -i. :) fbcon uses a
TRUECOLOR visual at depths > 8.


> It's a pre-existing bug, but should we also try to restore the fbdev lut
> in drm_fb_helper_restore_fbdev_mode_unlocked()? Would be yet another bug,
> but might be relevant for your use-case. Just try to run both an fbdev
> application and some kms-native thing, and then SIGKILL the native kms
> app.
> 
> But since pre-existing not really required, and probably too much effort.

I suspect something like that indeed needs to be done though. E.g.
killing Xorg results in fbcon continuing to use the LUT set by Xorg.


-- 
Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer

Re: [Nouveau] [PATCH 01/11] drm/fb-helper: do a generic fb_setcmap helper in terms of crtc .gamma_set

[Daniel Vetter]

On Wed, Jun 21, 2017 at 04:59:31PM +0900, Michel Dänzer wrote:
> On 21/06/17 04:38 PM, Daniel Vetter wrote:
> > On Tue, Jun 20, 2017 at 09:25:25PM +0200, Peter Rosin wrote:
> >> This makes the redundant fb helpers .load_lut, .gamma_set and .gamma_get
> >> totally obsolete.
> >>
> >> I think the gamma_store can end up invalid on error. But the way I read
> >> it, that can happen in drm_mode_gamma_set_ioctl as well, so why should
> >> this pesky legacy fbdev stuff be any better?
> >>
> >> drm_fb_helper_save_lut_atomic justs saves the gamma lut for later. However,
> >> it saves it to the gamma_store which should already be up to date with what
> >> .gamma_get would return and is thus a nop. So, zap it.
> > 
> > Removing drm_fb_helper_save_lut_atomic should be a separate patch I
> > think.
> >  
> >> Signed-off-by: Peter Rosin <peda@axentia.se>
> 
> [...]
> 
> >> @@ -1167,50 +1150,6 @@ void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
> >>  }
> >>  EXPORT_SYMBOL(drm_fb_helper_set_suspend_unlocked);
> >>  
> >> -static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green,
> >> -		     u16 blue, u16 regno, struct fb_info *info)
> >> -{
> >> -	struct drm_fb_helper *fb_helper = info->par;
> >> -	struct drm_framebuffer *fb = fb_helper->fb;
> >> -
> >> -	if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
> > 
> > This case here seems gone, and it was also the pièce de résistance when I
> > tried tackling fbdev lut support. As far as I understand this stuff we do
> > not support FB_VISUAL_TRUECOLOR palette, and all that bitshifting here is
> > pointless. But I'm honestly not really clear.
> > 
> > I think removing this case should also be a separate patch, and I'd very
> > much prefer that someone with some fbdev-clue would ack it.
> 
> No need for anyone with fbdev-clue, just run fbset -i. :) fbcon uses a
> TRUECOLOR visual at depths > 8.

Then I understand even less what exactly this code does ... Should we keep
it? Is it just pure cargo-cult? Only needed when we'd change the color
depth of the fbdev buffer, which we never do at runtime?

> > It's a pre-existing bug, but should we also try to restore the fbdev lut
> > in drm_fb_helper_restore_fbdev_mode_unlocked()? Would be yet another bug,
> > but might be relevant for your use-case. Just try to run both an fbdev
> > application and some kms-native thing, and then SIGKILL the native kms
> > app.
> > 
> > But since pre-existing not really required, and probably too much effort.
> 
> I suspect something like that indeed needs to be done though. E.g.
> killing Xorg results in fbcon continuing to use the LUT set by Xorg.

Ok, the only trouble with that is atomic kms locking, which requires that
we can only do 1 commit per lock-holding time, and also
drm_modeset_lock_all is an evil hack and needs to be phased out. Two
solutions:

- We just update the lut after we've dropped the locks again in
  restore_fbdev_mode.
- We need both a legacy path, in restore_fbdev_mode_legacy, and an atomic
  path in restore_fbdev_mode_atomic. The latter cannot use the gamme_set
  callback, since that would call drm_atomic_helper_legacy_gamma_set for
  atomic drivers, which would result in two calls to drm_atomic_commit in
  one critical sections. Instead that needs to open-code the logic in
  drm_atomic_helper_legacy_gamma_set and integrate it into the overall
  fbdev restore commit.

The 2nd option is a bit more typing, but much cleaner. It also fits better
into some of the refactoring plans I have (I want to get rid of
drm_modeset_lock_all in the fbdev emulation). And has the benefit of
giving drivers a bit more complex fbdev emulation atomic commits, which
would be good for testing I think.

Cheers, Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

Re: [Nouveau] [PATCH 01/11] drm/fb-helper: do a generic fb_setcmap helper in terms of crtc .gamma_set

[Michel Dänzer]

On 21/06/17 05:14 PM, Daniel Vetter wrote:
> On Wed, Jun 21, 2017 at 04:59:31PM +0900, Michel Dänzer wrote:
>> On 21/06/17 04:38 PM, Daniel Vetter wrote:
>>> On Tue, Jun 20, 2017 at 09:25:25PM +0200, Peter Rosin wrote:
>>>> This makes the redundant fb helpers .load_lut, .gamma_set and .gamma_get
>>>> totally obsolete.
>>>>
>>>> I think the gamma_store can end up invalid on error. But the way I read
>>>> it, that can happen in drm_mode_gamma_set_ioctl as well, so why should
>>>> this pesky legacy fbdev stuff be any better?
>>>>
>>>> drm_fb_helper_save_lut_atomic justs saves the gamma lut for later. However,
>>>> it saves it to the gamma_store which should already be up to date with what
>>>> .gamma_get would return and is thus a nop. So, zap it.
>>>
>>> Removing drm_fb_helper_save_lut_atomic should be a separate patch I
>>> think.
>>>  
>>>> Signed-off-by: Peter Rosin <peda@axentia.se>
>>
>> [...]
>>
>>>> @@ -1167,50 +1150,6 @@ void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
>>>>  }
>>>>  EXPORT_SYMBOL(drm_fb_helper_set_suspend_unlocked);
>>>>  
>>>> -static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green,
>>>> -		     u16 blue, u16 regno, struct fb_info *info)
>>>> -{
>>>> -	struct drm_fb_helper *fb_helper = info->par;
>>>> -	struct drm_framebuffer *fb = fb_helper->fb;
>>>> -
>>>> -	if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
>>>
>>> This case here seems gone, and it was also the pièce de résistance when I
>>> tried tackling fbdev lut support. As far as I understand this stuff we do
>>> not support FB_VISUAL_TRUECOLOR palette, and all that bitshifting here is
>>> pointless. But I'm honestly not really clear.
>>>
>>> I think removing this case should also be a separate patch, and I'd very
>>> much prefer that someone with some fbdev-clue would ack it.
>>
>> No need for anyone with fbdev-clue, just run fbset -i. :)

Adding Bartlomiej and the linux-fbdev list, just in case I'm wrong below.


>> fbcon uses a TRUECOLOR visual at depths > 8.
> 
> Then I understand even less what exactly this code does ... Should we keep
> it?

I think we need it. It updates the entries of info->pseudo_palette,
which is kind of a pseudocolor palette mapping 16 indices to pixel
values to write to the framebuffer.

If the setcolreg hook is removed, the setcmap hook needs to do this instead.


-- 
Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer

Re: [PATCH 01/11] drm/fb-helper: do a generic fb_setcmap helper in terms of crtc .gamma_set

[Peter Rosin]

On 2017-06-21 09:38, Daniel Vetter wrote:
> On Tue, Jun 20, 2017 at 09:25:25PM +0200, Peter Rosin wrote:
>> This makes the redundant fb helpers .load_lut, .gamma_set and .gamma_get
>> totally obsolete.
>>
>> I think the gamma_store can end up invalid on error. But the way I read
>> it, that can happen in drm_mode_gamma_set_ioctl as well, so why should
>> this pesky legacy fbdev stuff be any better?
>>
>> drm_fb_helper_save_lut_atomic justs saves the gamma lut for later. However,
>> it saves it to the gamma_store which should already be up to date with what
>> .gamma_get would return and is thus a nop. So, zap it.
> 
> Removing drm_fb_helper_save_lut_atomic should be a separate patch I
> think.

Then 3 patches would be needed, first some hybrid thing that does it the
old way, but also stores the lut in .gamma_store, then the split-out that
removes drm_fb_helper_save_lut_atomic, then whatever is needed to get
to the desired code. I can certainly do that, but do you want me to?

I.e., the statement that drm_fb_helper_save_lut_atomic is a nop is only
true when (part of) the other patch is also considered.

>> Signed-off-by: Peter Rosin <peda@axentia.se>
> 
>> ---
>>  drivers/gpu/drm/drm_fb_helper.c | 131 ++++++++++++----------------------------
>>  1 file changed, 40 insertions(+), 91 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
>> index 574af01..cc2d55d 100644
>> --- a/drivers/gpu/drm/drm_fb_helper.c
>> +++ b/drivers/gpu/drm/drm_fb_helper.c
>> @@ -229,22 +229,6 @@ int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
>>  }
>>  EXPORT_SYMBOL(drm_fb_helper_remove_one_connector);
>>  
>> -static void drm_fb_helper_save_lut_atomic(struct drm_crtc *crtc, struct drm_fb_helper *helper)
>> -{
>> -	uint16_t *r_base, *g_base, *b_base;
>> -	int i;
>> -
>> -	if (helper->funcs->gamma_get == NULL)
>> -		return;
>> -
>> -	r_base = crtc->gamma_store;
>> -	g_base = r_base + crtc->gamma_size;
>> -	b_base = g_base + crtc->gamma_size;
>> -
>> -	for (i = 0; i < crtc->gamma_size; i++)
>> -		helper->funcs->gamma_get(crtc, &r_base[i], &g_base[i], &b_base[i], i);
>> -}
>> -
>>  static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc)
>>  {
>>  	uint16_t *r_base, *g_base, *b_base;
>> @@ -285,7 +269,6 @@ int drm_fb_helper_debug_enter(struct fb_info *info)
>>  			if (drm_drv_uses_atomic_modeset(mode_set->crtc->dev))
>>  				continue;
>>  
>> -			drm_fb_helper_save_lut_atomic(mode_set->crtc, helper);
>>  			funcs->mode_set_base_atomic(mode_set->crtc,
>>  						    mode_set->fb,
>>  						    mode_set->x,
>> @@ -1167,50 +1150,6 @@ void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
>>  }
>>  EXPORT_SYMBOL(drm_fb_helper_set_suspend_unlocked);
>>  
>> -static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green,
>> -		     u16 blue, u16 regno, struct fb_info *info)
>> -{
>> -	struct drm_fb_helper *fb_helper = info->par;
>> -	struct drm_framebuffer *fb = fb_helper->fb;
>> -
>> -	if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
> 
> This case here seems gone, and it was also the pièce de résistance when I
> tried tackling fbdev lut support. As far as I understand this stuff we do
> not support FB_VISUAL_TRUECOLOR palette, and all that bitshifting here is
> pointless. But I'm honestly not really clear.

Oops, sorry, I simply missed that, I'll have a closer look...

> I think removing this case should also be a separate patch, and I'd very
> much prefer that someone with some fbdev-clue would ack it.
> 
>> -		u32 *palette;
>> -		u32 value;
>> -		/* place color in psuedopalette */
>> -		if (regno > 16)
>> -			return -EINVAL;
>> -		palette = (u32 *)info->pseudo_palette;
>> -		red >>= (16 - info->var.red.length);
>> -		green >>= (16 - info->var.green.length);
>> -		blue >>= (16 - info->var.blue.length);
>> -		value = (red << info->var.red.offset) |
>> -			(green << info->var.green.offset) |
>> -			(blue << info->var.blue.offset);
>> -		if (info->var.transp.length > 0) {
>> -			u32 mask = (1 << info->var.transp.length) - 1;
>> -
>> -			mask <<= info->var.transp.offset;
>> -			value |= mask;
>> -		}
>> -		palette[regno] = value;
>> -		return 0;
>> -	}
>> -
>> -	/*
>> -	 * The driver really shouldn't advertise pseudo/directcolor
>> -	 * visuals if it can't deal with the palette.
>> -	 */
>> -	if (WARN_ON(!fb_helper->funcs->gamma_set ||
>> -		    !fb_helper->funcs->gamma_get))
>> -		return -EINVAL;
>> -
>> -	WARN_ON(fb->format->cpp[0] != 1);
>> -
>> -	fb_helper->funcs->gamma_set(crtc, red, green, blue, regno);
>> -
>> -	return 0;
>> -}
>> -
>>  /**
>>   * drm_fb_helper_setcmap - implementation for &fb_ops.fb_setcmap
>>   * @cmap: cmap to set
>> @@ -1220,51 +1159,61 @@ int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
>>  {
>>  	struct drm_fb_helper *fb_helper = info->par;
>>  	struct drm_device *dev = fb_helper->dev;
>> -	const struct drm_crtc_helper_funcs *crtc_funcs;
>> -	u16 *red, *green, *blue, *transp;
>> +	struct drm_modeset_acquire_ctx ctx;
>>  	struct drm_crtc *crtc;
>> -	int i, j, rc = 0;
>> -	int start;
>> +	u16 *r, *g, *b;
>> +	int i, ret;
>>  
>>  	if (oops_in_progress)
>>  		return -EBUSY;
>>  
>> -	drm_modeset_lock_all(dev);
>> +	if (cmap->start + cmap->len < cmap->start)
>> +		return -EINVAL;
>> +
>> +	drm_modeset_acquire_init(&ctx, 0);
>> +retry:
>> +	ret = drm_modeset_lock_all_ctx(dev, &ctx);
>> +	if (ret)
>> +		goto out;
>>  	if (!drm_fb_helper_is_bound(fb_helper)) {
>> -		drm_modeset_unlock_all(dev);
>> -		return -EBUSY;
>> +		ret = -EBUSY;
>> +		goto out;
>>  	}
>>  
>>  	for (i = 0; i < fb_helper->crtc_count; i++) {
>>  		crtc = fb_helper->crtc_info[i].mode_set.crtc;
>> -		crtc_funcs = crtc->helper_private;
>> -
>> -		red = cmap->red;
>> -		green = cmap->green;
>> -		blue = cmap->blue;
>> -		transp = cmap->transp;
>> -		start = cmap->start;
>> +		if (!crtc->funcs->gamma_set || !crtc->gamma_size) {
>> +			ret = -EINVAL;
>> +			goto out;
>> +		}
>>  
>> -		for (j = 0; j < cmap->len; j++) {
>> -			u16 hred, hgreen, hblue, htransp = 0xffff;
>> +		if (cmap->start + cmap->len > crtc->gamma_size) {
>> +			ret = -EINVAL;
>> +			goto out;
>> +		}
>>  
>> -			hred = *red++;
>> -			hgreen = *green++;
>> -			hblue = *blue++;
>> +		r = crtc->gamma_store;
>> +		g = r + crtc->gamma_size;
>> +		b = g + crtc->gamma_size;
>>  
>> -			if (transp)
>> -				htransp = *transp++;
>> +		memcpy(r + cmap->start, cmap->red, cmap->len * sizeof(u16));
>> +		memcpy(g + cmap->start, cmap->green, cmap->len * sizeof(u16));
>> +		memcpy(b + cmap->start, cmap->blue, cmap->len * sizeof(u16));
>>  
>> -			rc = setcolreg(crtc, hred, hgreen, hblue, start++, info);
>> -			if (rc)
>> -				goto out;
>> -		}
>> -		if (crtc_funcs->load_lut)
>> -			crtc_funcs->load_lut(crtc);
>> +		ret = crtc->funcs->gamma_set(crtc, r, g, b,
>> +					     crtc->gamma_size, &ctx);
>> +		if (ret)
>> +			break;
>>  	}
>> - out:
>> -	drm_modeset_unlock_all(dev);
>> -	return rc;
>> +out:
>> +	if (ret == -EDEADLK) {
>> +		drm_modeset_backoff(&ctx);
>> +		goto retry;
>> +	}
>> +	drm_modeset_drop_locks(&ctx);
>> +	drm_modeset_acquire_fini(&ctx);
>> +
>> +	return ret;
> 
> It's a pre-existing bug, but should we also try to restore the fbdev lut
> in drm_fb_helper_restore_fbdev_mode_unlocked()? Would be yet another bug,
> but might be relevant for your use-case. Just try to run both an fbdev
> application and some kms-native thing, and then SIGKILL the native kms
> app.
> 
> But since pre-existing not really required, and probably too much effort.

Good thing too, because I don't really know my way around this code...

Cheers,
peda

> Thanks, Daniel
> 
>>  }
>>  EXPORT_SYMBOL(drm_fb_helper_setcmap);
>>  
>> -- 
>> 2.1.4
>>
>> _______________________________________________
>> dri-devel mailing list
>> dri-devel@lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/dri-devel
> 

Re: [PATCH 08/11] drm: nouveau: remove dead code and pointless local lut storage

[Peter Rosin]

On 2017-06-20 21:25, Peter Rosin wrote:
> The redundant fb helpers .load_lut, .gamma_set and .gamma_get are
> no longer used. Remove the dead code and hook up the crtc .gamma_set
> to use the crtc gamma_store directly instead of duplicating that
> info locally.

[...]

> -	for (i = 0; i < 256; i++) {
> -		u16 r = nv_crtc->lut.r[i] >> 2;
> -		u16 g = nv_crtc->lut.g[i] >> 2;
> -		u16 b = nv_crtc->lut.b[i] >> 2;
> +	r = crtc->gamma_store;
> +	g = r + crtc->gamma_size;
> +	b = g + crtc->gamma_size;
>  
> +	for (i = 0; i < 256; i++) {
>  		if (disp->disp->oclass < GF110_DISP) {
> -			writew(r + 0x0000, lut + (i * 0x08) + 0);
> -			writew(g + 0x0000, lut + (i * 0x08) + 2);
> -			writew(b + 0x0000, lut + (i * 0x08) + 4);
> +			writew((*r++ >> 2) + 0x0000, lut + (i * 0x08) + 0);
> +			writew((*g++ >> 2) + 0x0000, lut + (i * 0x08) + 2);
> +			writew((*b++ >> 2) + 0x0000, lut + (i * 0x08) + 4);
>  		} else {
> -			writew(r + 0x6000, lut + (i * 0x20) + 0);
> -			writew(g + 0x6000, lut + (i * 0x20) + 2);
> -			writew(b + 0x6000, lut + (i * 0x20) + 4);
> +			writew((*r++ >> 2) + 0x6000, lut + (i * 0x20) + 0);
> +			writew((*g++ >> 2) + 0x6000, lut + (i * 0x20) + 2);
> +			writew((*b++ >> 2) + 0x6000, lut + (i * 0x20) + 4);
>  		}
>  	}
>  }

I forgot to mention this, but the above is very strange for
disp->disp->oclass >= GF110_DISP because 0x6000 interferes with
the 14 bits that appear to be the lut depth in the registers.

I suspect some other bit-shift should be used for that case?

Someone should probably consult a datasheet...

Cheers,
peda

Re: [PATCH 11/11] drm: remove unused and redundant callbacks

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 2979 bytes --]

Hi Peter,

[auto build test ERROR on drm/drm-next]
[also build test ERROR on next-20170621]
[cannot apply to v4.12-rc6]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Peter-Rosin/improve-the-fb_setcmap-helper/20170621-205441
base:   git://people.freedesktop.org/~airlied/linux.git drm-next
config: arm-allmodconfig (attached as .config)
compiler: arm-linux-gnueabi-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
        wget https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=arm 

All errors (new ones prefixed by >>):

>> drivers/gpu//drm/armada/armada_fbdev.c:121:2: error: unknown field 'gamma_set' specified in initializer
     .gamma_set = armada_drm_crtc_gamma_set,
     ^
>> drivers/gpu//drm/armada/armada_fbdev.c:121:15: error: initialization from incompatible pointer type [-Werror=incompatible-pointer-types]
     .gamma_set = armada_drm_crtc_gamma_set,
                  ^~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/gpu//drm/armada/armada_fbdev.c:121:15: note: (near initialization for 'armada_fb_helper_funcs.fb_probe')
>> drivers/gpu//drm/armada/armada_fbdev.c:122:2: error: unknown field 'gamma_get' specified in initializer
     .gamma_get = armada_drm_crtc_gamma_get,
     ^
   drivers/gpu//drm/armada/armada_fbdev.c:122:15: error: initialization from incompatible pointer type [-Werror=incompatible-pointer-types]
     .gamma_get = armada_drm_crtc_gamma_get,
                  ^~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/gpu//drm/armada/armada_fbdev.c:122:15: note: (near initialization for 'armada_fb_helper_funcs.initial_config')
   cc1: some warnings being treated as errors

vim +/gamma_set +121 drivers/gpu//drm/armada/armada_fbdev.c

96f60e37 Russell King   2012-08-15  115  			ret = 1;
96f60e37 Russell King   2012-08-15  116  	}
96f60e37 Russell King   2012-08-15  117  	return ret;
96f60e37 Russell King   2012-08-15  118  }
96f60e37 Russell King   2012-08-15  119  
3a493879 Thierry Reding 2014-06-27  120  static const struct drm_fb_helper_funcs armada_fb_helper_funcs = {
96f60e37 Russell King   2012-08-15 @121  	.gamma_set	= armada_drm_crtc_gamma_set,
96f60e37 Russell King   2012-08-15 @122  	.gamma_get	= armada_drm_crtc_gamma_get,
96f60e37 Russell King   2012-08-15  123  	.fb_probe	= armada_fb_probe,
96f60e37 Russell King   2012-08-15  124  };
96f60e37 Russell King   2012-08-15  125  

:::::: The code at line 121 was first introduced by commit
:::::: 96f60e37dc66091bde8d5de136ff6fda09f2d799 DRM: Armada: Add Armada DRM driver

:::::: TO: Russell King <rmk+kernel@arm.linux.org.uk>
:::::: CC: Russell King <rmk+kernel@arm.linux.org.uk>

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 62456 bytes --]

Re: [PATCH 01/11] drm/fb-helper: do a generic fb_setcmap helper in terms of crtc .gamma_set

[Daniel Vetter]

On Wed, Jun 21, 2017 at 11:40:52AM +0200, Peter Rosin wrote:
> On 2017-06-21 09:38, Daniel Vetter wrote:
> > On Tue, Jun 20, 2017 at 09:25:25PM +0200, Peter Rosin wrote:
> >> This makes the redundant fb helpers .load_lut, .gamma_set and .gamma_get
> >> totally obsolete.
> >>
> >> I think the gamma_store can end up invalid on error. But the way I read
> >> it, that can happen in drm_mode_gamma_set_ioctl as well, so why should
> >> this pesky legacy fbdev stuff be any better?
> >>
> >> drm_fb_helper_save_lut_atomic justs saves the gamma lut for later. However,
> >> it saves it to the gamma_store which should already be up to date with what
> >> .gamma_get would return and is thus a nop. So, zap it.
> > 
> > Removing drm_fb_helper_save_lut_atomic should be a separate patch I
> > think.
> 
> Then 3 patches would be needed, first some hybrid thing that does it the
> old way, but also stores the lut in .gamma_store, then the split-out that
> removes drm_fb_helper_save_lut_atomic, then whatever is needed to get
> to the desired code. I can certainly do that, but do you want me to?

Explain that in the commit message and it's fine.

> > It's a pre-existing bug, but should we also try to restore the fbdev lut
> > in drm_fb_helper_restore_fbdev_mode_unlocked()? Would be yet another bug,
> > but might be relevant for your use-case. Just try to run both an fbdev
> > application and some kms-native thing, and then SIGKILL the native kms
> > app.
> > 
> > But since pre-existing not really required, and probably too much effort.
> 
> Good thing too, because I don't really know my way around this code...

Btw I cc'ed you on one of my patches in the fbdev locking series, we might
need to do the same legacy vs. atomic split for the new lut code as I did
for dpms. The rule with atomic is that you can't do multiple commits under
drm_modeset_lock_all, you either have to do one overall atomic commit
(preferred) or drop&reacquire locks again. This matters for LUT since
you're updating the LUT on all CRTCs, which when using the gamma_set
atomic helper would be multiple commits :-/

Using the dpms patch as template it shouldn't be too hard to address that
for your patch here too.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

Re: [PATCH 11/11] drm: remove unused and redundant callbacks

[Daniel Vetter]

On Thu, Jun 22, 2017 at 12:34:36AM +0800, kbuild test robot wrote:
> Hi Peter,
> 
> [auto build test ERROR on drm/drm-next]
> [also build test ERROR on next-20170621]
> [cannot apply to v4.12-rc6]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
> 
> url:    https://github.com/0day-ci/linux/commits/Peter-Rosin/improve-the-fb_setcmap-helper/20170621-205441
> base:   git://people.freedesktop.org/~airlied/linux.git drm-next
> config: arm-allmodconfig (attached as .config)
> compiler: arm-linux-gnueabi-gcc (Debian 6.1.1-9) 6.1.1 20160705
> reproduce:
>         wget https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # save the attached .config to linux build tree
>         make.cross ARCH=arm 
> 
> All errors (new ones prefixed by >>):
> 
> >> drivers/gpu//drm/armada/armada_fbdev.c:121:2: error: unknown field 'gamma_set' specified in initializer
>      .gamma_set = armada_drm_crtc_gamma_set,

Looks like you've missed at least the armada driver in your conversion?
-Daniel

>      ^
> >> drivers/gpu//drm/armada/armada_fbdev.c:121:15: error: initialization from incompatible pointer type [-Werror=incompatible-pointer-types]
>      .gamma_set = armada_drm_crtc_gamma_set,
>                   ^~~~~~~~~~~~~~~~~~~~~~~~~
>    drivers/gpu//drm/armada/armada_fbdev.c:121:15: note: (near initialization for 'armada_fb_helper_funcs.fb_probe')
> >> drivers/gpu//drm/armada/armada_fbdev.c:122:2: error: unknown field 'gamma_get' specified in initializer
>      .gamma_get = armada_drm_crtc_gamma_get,
>      ^
>    drivers/gpu//drm/armada/armada_fbdev.c:122:15: error: initialization from incompatible pointer type [-Werror=incompatible-pointer-types]
>      .gamma_get = armada_drm_crtc_gamma_get,
>                   ^~~~~~~~~~~~~~~~~~~~~~~~~
>    drivers/gpu//drm/armada/armada_fbdev.c:122:15: note: (near initialization for 'armada_fb_helper_funcs.initial_config')
>    cc1: some warnings being treated as errors
> 
> vim +/gamma_set +121 drivers/gpu//drm/armada/armada_fbdev.c
> 
> 96f60e37 Russell King   2012-08-15  115  			ret = 1;
> 96f60e37 Russell King   2012-08-15  116  	}
> 96f60e37 Russell King   2012-08-15  117  	return ret;
> 96f60e37 Russell King   2012-08-15  118  }
> 96f60e37 Russell King   2012-08-15  119  
> 3a493879 Thierry Reding 2014-06-27  120  static const struct drm_fb_helper_funcs armada_fb_helper_funcs = {
> 96f60e37 Russell King   2012-08-15 @121  	.gamma_set	= armada_drm_crtc_gamma_set,
> 96f60e37 Russell King   2012-08-15 @122  	.gamma_get	= armada_drm_crtc_gamma_get,
> 96f60e37 Russell King   2012-08-15  123  	.fb_probe	= armada_fb_probe,
> 96f60e37 Russell King   2012-08-15  124  };
> 96f60e37 Russell King   2012-08-15  125  
> 
> :::::: The code at line 121 was first introduced by commit
> :::::: 96f60e37dc66091bde8d5de136ff6fda09f2d799 DRM: Armada: Add Armada DRM driver
> 
> :::::: TO: Russell King <rmk+kernel@arm.linux.org.uk>
> :::::: CC: Russell King <rmk+kernel@arm.linux.org.uk>
> 
> ---
> 0-DAY kernel test infrastructure                Open Source Technology Center
> https://lists.01.org/pipermail/kbuild-all                   Intel Corporation


> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel


-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

Re: [PATCH 11/11] drm: remove unused and redundant callbacks

[Boris Brezillon]

On Thu, 22 Jun 2017 08:37:55 +0200
Daniel Vetter <daniel@ffwll.ch> wrote:

> On Thu, Jun 22, 2017 at 12:34:36AM +0800, kbuild test robot wrote:
> > Hi Peter,
> > 
> > [auto build test ERROR on drm/drm-next]
> > [also build test ERROR on next-20170621]
> > [cannot apply to v4.12-rc6]
> > [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
> > 
> > url:    https://github.com/0day-ci/linux/commits/Peter-Rosin/improve-the-fb_setcmap-helper/20170621-205441
> > base:   git://people.freedesktop.org/~airlied/linux.git drm-next
> > config: arm-allmodconfig (attached as .config)
> > compiler: arm-linux-gnueabi-gcc (Debian 6.1.1-9) 6.1.1 20160705
> > reproduce:
> >         wget https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> >         chmod +x ~/bin/make.cross
> >         # save the attached .config to linux build tree
> >         make.cross ARCH=arm 
> > 
> > All errors (new ones prefixed by >>):
> >   
> > >> drivers/gpu//drm/armada/armada_fbdev.c:121:2: error: unknown field 'gamma_set' specified in initializer  
> >      .gamma_set = armada_drm_crtc_gamma_set,  
> 
> Looks like you've missed at least the armada driver in your conversion?

Already fixed in v2 ;-).

Re: [PATCH 01/11] drm/fb-helper: do a generic fb_setcmap helper in terms of crtc .gamma_set

[Peter Rosin]

On 2017-06-22 08:36, Daniel Vetter wrote:
> On Wed, Jun 21, 2017 at 11:40:52AM +0200, Peter Rosin wrote:
>> On 2017-06-21 09:38, Daniel Vetter wrote:
>>> On Tue, Jun 20, 2017 at 09:25:25PM +0200, Peter Rosin wrote:
>>>> This makes the redundant fb helpers .load_lut, .gamma_set and .gamma_get
>>>> totally obsolete.
>>>>
>>>> I think the gamma_store can end up invalid on error. But the way I read
>>>> it, that can happen in drm_mode_gamma_set_ioctl as well, so why should
>>>> this pesky legacy fbdev stuff be any better?
>>>>
>>>> drm_fb_helper_save_lut_atomic justs saves the gamma lut for later. However,
>>>> it saves it to the gamma_store which should already be up to date with what
>>>> .gamma_get would return and is thus a nop. So, zap it.
>>>
>>> Removing drm_fb_helper_save_lut_atomic should be a separate patch I
>>> think.
>>
>> Then 3 patches would be needed, first some hybrid thing that does it the
>> old way, but also stores the lut in .gamma_store, then the split-out that
>> removes drm_fb_helper_save_lut_atomic, then whatever is needed to get
>> to the desired code. I can certainly do that, but do you want me to?
> 
> Explain that in the commit message and it's fine.

I did the split in v2, I assume that's ok too. Better in case anyone ever
needs to run a bisect on this...

>>> It's a pre-existing bug, but should we also try to restore the fbdev lut
>>> in drm_fb_helper_restore_fbdev_mode_unlocked()? Would be yet another bug,
>>> but might be relevant for your use-case. Just try to run both an fbdev
>>> application and some kms-native thing, and then SIGKILL the native kms
>>> app.
>>>
>>> But since pre-existing not really required, and probably too much effort.
>>
>> Good thing too, because I don't really know my way around this code...
> 
> Btw I cc'ed you on one of my patches in the fbdev locking series, we might
> need to do the same legacy vs. atomic split for the new lut code as I did
> for dpms. The rule with atomic is that you can't do multiple commits under
> drm_modeset_lock_all, you either have to do one overall atomic commit
> (preferred) or drop&reacquire locks again. This matters for LUT since
> you're updating the LUT on all CRTCs, which when using the gamma_set
> atomic helper would be multiple commits :-/

Ahh, ok, I see the problem.

> Using the dpms patch as template it shouldn't be too hard to address that
> for your patch here too.

Hmm, in that patch you handle the legacy case in a separate function, and
doing that for the lut case looks difficult when the atomic commit happens
inside the helper (typically drm_atomic_helper_legacy_gamma_set which
could perhaps be handled, but a real drag to handle for drivers that have
a custom crtc .gamma_set).

So, I'm aiming for the drop&reacquire approach...

However, I don't have all of that series, and I suspect that is why I do
not have any fb_helper->lock.

I'll send my best guess as a follow-up to patch 3/14 in v2.

Cheers,
peda

Re: [PATCH 01/11] drm/fb-helper: do a generic fb_setcmap helper in terms of crtc .gamma_set

[Daniel Vetter]

On Thu, Jun 22, 2017 at 10:48:10AM +0200, Peter Rosin wrote:
> On 2017-06-22 08:36, Daniel Vetter wrote:
> > On Wed, Jun 21, 2017 at 11:40:52AM +0200, Peter Rosin wrote:
> >> On 2017-06-21 09:38, Daniel Vetter wrote:
> >>> On Tue, Jun 20, 2017 at 09:25:25PM +0200, Peter Rosin wrote:
> >>>> This makes the redundant fb helpers .load_lut, .gamma_set and .gamma_get
> >>>> totally obsolete.
> >>>>
> >>>> I think the gamma_store can end up invalid on error. But the way I read
> >>>> it, that can happen in drm_mode_gamma_set_ioctl as well, so why should
> >>>> this pesky legacy fbdev stuff be any better?
> >>>>
> >>>> drm_fb_helper_save_lut_atomic justs saves the gamma lut for later. However,
> >>>> it saves it to the gamma_store which should already be up to date with what
> >>>> .gamma_get would return and is thus a nop. So, zap it.
> >>>
> >>> Removing drm_fb_helper_save_lut_atomic should be a separate patch I
> >>> think.
> >>
> >> Then 3 patches would be needed, first some hybrid thing that does it the
> >> old way, but also stores the lut in .gamma_store, then the split-out that
> >> removes drm_fb_helper_save_lut_atomic, then whatever is needed to get
> >> to the desired code. I can certainly do that, but do you want me to?
> > 
> > Explain that in the commit message and it's fine.
> 
> I did the split in v2, I assume that's ok too. Better in case anyone ever
> needs to run a bisect on this...
> 
> >>> It's a pre-existing bug, but should we also try to restore the fbdev lut
> >>> in drm_fb_helper_restore_fbdev_mode_unlocked()? Would be yet another bug,
> >>> but might be relevant for your use-case. Just try to run both an fbdev
> >>> application and some kms-native thing, and then SIGKILL the native kms
> >>> app.
> >>>
> >>> But since pre-existing not really required, and probably too much effort.
> >>
> >> Good thing too, because I don't really know my way around this code...
> > 
> > Btw I cc'ed you on one of my patches in the fbdev locking series, we might
> > need to do the same legacy vs. atomic split for the new lut code as I did
> > for dpms. The rule with atomic is that you can't do multiple commits under
> > drm_modeset_lock_all, you either have to do one overall atomic commit
> > (preferred) or drop&reacquire locks again. This matters for LUT since
> > you're updating the LUT on all CRTCs, which when using the gamma_set
> > atomic helper would be multiple commits :-/
> 
> Ahh, ok, I see the problem.
> 
> > Using the dpms patch as template it shouldn't be too hard to address that
> > for your patch here too.
> 
> Hmm, in that patch you handle the legacy case in a separate function, and
> doing that for the lut case looks difficult when the atomic commit happens
> inside the helper (typically drm_atomic_helper_legacy_gamma_set which
> could perhaps be handled, but a real drag to handle for drivers that have
> a custom crtc .gamma_set).

Yeah, that's essentially why you need 2 functions. Legacy one calls the
legacy interfaces, the atomic one calls the new fancy atomic property
stuff directly (i.e. it open-codes the property setting dance from the
helper, but with one atomic commit across all crtc).

The reason that the legacy callback functions are helpers and not just
default behavior is that I expected some drivers to need special hacks to
keep their existing legacy kms userspace working. Atomic helpers unified
behaviour a lot that beforehand was slightly inconsistent. I somewhat
expect that long-term we'll unexport all the compat helpers and just make
them the default for all atomic drivers.

> So, I'm aiming for the drop&reacquire approach...

Hm, I prefer the open-coding, that's at least what we do everywhere else.
Has the benefit that it's more atomic (one commit for everything).

> However, I don't have all of that series, and I suspect that is why I do
> not have any fb_helper->lock.

Oh sorry, entire series is on dri-devel. I can do a git branch too if you
need one, atm it's in my general pile:

https://cgit.freedesktop.org/~danvet/drm/log/

Cheers, Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch