[PATCH V10 26/46] drm/amd/display: Add support for sRGB EOTF in DEGAM block

Melissa Wen mwen at igalia.com
Wed Jul 9 19:45:45 UTC 2025



On 17/06/2025 00:17, Alex Hung wrote:
> Expose one 1D curve colorop with support for
> DRM_COLOROP_1D_CURVE_SRGB_EOTF and program HW to perform
> the sRGB transform when the colorop is not in bypass.
>
> With this change the following IGT test passes:
> kms_colorop --run plane-XR30-XR30-srgb_eotf
>
> The color pipeline now consists of a single colorop:
> 1. 1D curve colorop w/ sRGB EOTF
>
> Signed-off-by: Alex Hung <alex.hung at amd.com>
> Co-developed-by: Harry Wentland <harry.wentland at amd.com>
> Signed-off-by: Harry Wentland <harry.wentland at amd.com>
> Reviewed-by: Daniel Stone <daniels at collabora.com>
> ---
> V10:
>   - Replace DRM_ERROR by drm_err
>   - Creaet color pipeline when >= DCN_VERSION_3_0
>
> V9:
>   - Update function names by _plane_ (Chaitanya Kumar Borah)
>   - Update replace cleanup code by drm_colorop_pipeline_destroy (Simon Ser)
>
> v8:
>   - Fix incorrect && by || in __set_colorop_in_tf_1d_curve (Leo Li)
>
> v7:
>   - Fix checkpatch warnings
>    - Change switch "{ }" position
>    - Delete double ";"
>    - Delete "{ }" for single-line if-statement
>    - Add a new line at EOF
>    - Change SPDX-License-Identifier: GPL-2.0+ from // to /* */
>
> v6:
>   - cleanup if colorop alloc or init fails
>
>   .../gpu/drm/amd/display/amdgpu_dm/Makefile    |  3 +-
>   .../amd/display/amdgpu_dm/amdgpu_dm_color.c   | 86 +++++++++++++++++++
>   .../amd/display/amdgpu_dm/amdgpu_dm_colorop.c | 71 +++++++++++++++
>   .../amd/display/amdgpu_dm/amdgpu_dm_colorop.h | 34 ++++++++
>   .../amd/display/amdgpu_dm/amdgpu_dm_plane.c   | 16 ++++
>   5 files changed, 209 insertions(+), 1 deletion(-)
>   create mode 100644 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_colorop.c
>   create mode 100644 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_colorop.h
>
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/Makefile b/drivers/gpu/drm/amd/display/amdgpu_dm/Makefile
> index 7329b8cc2576..8e949fe77312 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/Makefile
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/Makefile
> @@ -39,7 +39,8 @@ AMDGPUDM = \
>   	amdgpu_dm_psr.o \
>   	amdgpu_dm_replay.o \
>   	amdgpu_dm_quirks.o \
> -	amdgpu_dm_wb.o
> +	amdgpu_dm_wb.o \
> +	amdgpu_dm_colorop.o
>   
>   ifdef CONFIG_DRM_AMD_DC_FP
>   AMDGPUDM += dc_fpu.o
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c
> index ebabfe3a512f..0b513ab5050f 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c
> @@ -668,6 +668,18 @@ amdgpu_tf_to_dc_tf(enum amdgpu_transfer_function tf)
>   	}
>   }
>   
> +static enum dc_transfer_func_predefined
> +amdgpu_colorop_tf_to_dc_tf(enum drm_colorop_curve_1d_type tf)
> +{
> +	switch (tf) {
> +	case DRM_COLOROP_1D_CURVE_SRGB_EOTF:
> +	case DRM_COLOROP_1D_CURVE_SRGB_INV_EOTF:
> +		return TRANSFER_FUNCTION_SRGB;
> +	default:
> +		return TRANSFER_FUNCTION_LINEAR;
> +	}
> +}
> +
>   static void __to_dc_lut3d_color(struct dc_rgb *rgb,
>   				const struct drm_color_lut lut,
>   				int bit_precision)
> @@ -1137,6 +1149,59 @@ __set_dm_plane_degamma(struct drm_plane_state *plane_state,
>   	return 0;
>   }
>   
> +static int
> +__set_colorop_in_tf_1d_curve(struct dc_plane_state *dc_plane_state,
> +		       struct drm_colorop_state *colorop_state)
> +{
> +	struct dc_transfer_func *tf = &dc_plane_state->in_transfer_func;
> +	struct drm_colorop *colorop = colorop_state->colorop;
> +	struct drm_device *drm = colorop->dev;
> +
> +	if (colorop->type != DRM_COLOROP_1D_CURVE ||
> +	    colorop_state->curve_1d_type != DRM_COLOROP_1D_CURVE_SRGB_EOTF)
> +		return -EINVAL;
> +
> +	if (colorop_state->bypass) {
> +		tf->type = TF_TYPE_BYPASS;
> +		tf->tf = TRANSFER_FUNCTION_LINEAR;
> +		return 0;
> +	}
> +
> +	drm_dbg(drm, "Degamma colorop with ID: %d\n", colorop->base.id);
> +
> +	tf->type = TF_TYPE_PREDEFINED;
> +	tf->tf = amdgpu_colorop_tf_to_dc_tf(colorop_state->curve_1d_type);
> +
> +	return 0;
> +}
> +
> +static int
> +__set_dm_plane_colorop_degamma(struct drm_plane_state *plane_state,
> +			       struct dc_plane_state *dc_plane_state,
> +			       struct drm_colorop *colorop)
> +{
> +	struct drm_colorop *old_colorop;
> +	struct drm_colorop_state *colorop_state = NULL, *new_colorop_state;
> +	struct drm_atomic_state *state = plane_state->state;
> +	int i = 0;
> +
> +	old_colorop = colorop;
> +
> +	/* 1st op: 1d curve - degamma */
> +	for_each_new_colorop_in_state(state, colorop, new_colorop_state, i) {
> +		if (new_colorop_state->colorop == old_colorop &&
> +		    new_colorop_state->curve_1d_type == DRM_COLOROP_1D_CURVE_SRGB_EOTF) {
> +			colorop_state = new_colorop_state;
> +			break;
> +		}
> +	}
> +
> +	if (!colorop_state)
> +		return -EINVAL;
> +
> +	return __set_colorop_in_tf_1d_curve(dc_plane_state, colorop_state);
> +}
> +
>   static int
>   amdgpu_dm_plane_set_color_properties(struct drm_plane_state *plane_state,
>   				     struct dc_plane_state *dc_plane_state)
> @@ -1187,6 +1252,24 @@ amdgpu_dm_plane_set_color_properties(struct drm_plane_state *plane_state,
>   	return 0;
>   }
>   
> +static int
> +amdgpu_dm_plane_set_colorop_properties(struct drm_plane_state *plane_state,
> +		       struct dc_plane_state *dc_plane_state)
> +{
> +	struct drm_colorop *colorop = plane_state->color_pipeline;
> +	int ret;
> +
> +	/* 1D Curve - DEGAM TF */
> +	if (!colorop)
> +		return -EINVAL;
> +
> +	ret = __set_dm_plane_colorop_degamma(plane_state, dc_plane_state, colorop);
> +	if (ret)
> +		return ret;
> +
> +	return 0;
> +}
> +
>   /**
>    * amdgpu_dm_update_plane_color_mgmt: Maps DRM color management to DC plane.
>    * @crtc: amdgpu_dm crtc state
> @@ -1283,5 +1366,8 @@ int amdgpu_dm_update_plane_color_mgmt(struct dm_crtc_state *crtc,
>   		dc_plane_state->input_csc_color_matrix.enable_adjustment = false;
>   	}
>   
> +	if (!amdgpu_dm_plane_set_colorop_properties(plane_state, dc_plane_state))
> +		return 0;
> +
>   	return amdgpu_dm_plane_set_color_properties(plane_state, dc_plane_state);
>   }
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_colorop.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_colorop.c
> new file mode 100644
> index 000000000000..9d371728b5fd
> --- /dev/null
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_colorop.c
> @@ -0,0 +1,71 @@
> +// SPDX-License-Identifier: MIT
> +/*
> + * Copyright 2023 Advanced Micro Devices, Inc.
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
> + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
> + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
> + * OTHER DEALINGS IN THE SOFTWARE.
> + *
> + * Authors: AMD
> + *
> + */
> +
> +#include <drm/drm_print.h>
> +#include <drm/drm_plane.h>
> +#include <drm/drm_property.h>
> +#include <drm/drm_colorop.h>
> +
> +#include "amdgpu_dm_colorop.h"
> +
> +const u64 amdgpu_dm_supported_degam_tfs =
> +	BIT(DRM_COLOROP_1D_CURVE_SRGB_EOTF);
> +
> +#define MAX_COLOR_PIPELINE_OPS 10
> +
> +int amdgpu_dm_initialize_default_pipeline(struct drm_plane *plane, struct drm_prop_enum_list *list)
> +{
> +	struct drm_colorop *ops[MAX_COLOR_PIPELINE_OPS];
> +	struct drm_device *dev = plane->dev;
> +	int ret;
> +	int i = 0;
> +
> +	memset(ops, 0, sizeof(ops));
> +
> +	/* 1D curve - DEGAM TF */
> +	ops[i] = kzalloc(sizeof(struct drm_colorop), GFP_KERNEL);
> +	if (!ops[i]) {
> +		ret = -ENOMEM;
> +		goto cleanup;
> +	}
> +
> +	ret = drm_plane_colorop_curve_1d_init(dev, ops[i], plane, amdgpu_dm_supported_degam_tfs);
> +	if (ret)
> +		goto cleanup;
> +
> +	list->type = ops[i]->base.id;
> +	list->name = kasprintf(GFP_KERNEL, "Color Pipeline %d", ops[i]->base.id);
> +
> +	return 0;
> +
> +cleanup:
> +	if (ret == -ENOMEM)
> +		drm_err(plane->dev, "KMS: Failed to allocate colorop\n");
> +
> +	drm_colorop_pipeline_destroy(plane);
> +
> +	return ret;
> +}
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_colorop.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_colorop.h
> new file mode 100644
> index 000000000000..3324e2a66079
> --- /dev/null
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_colorop.h
> @@ -0,0 +1,34 @@
> +/* SPDX-License-Identifier: MIT */
> +/*
> + * Copyright 2023 Advanced Micro Devices, Inc.
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
> + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
> + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
> + * OTHER DEALINGS IN THE SOFTWARE.
> + *
> + * Authors: AMD
> + *
> + */
> +
> +#ifndef __AMDGPU_DM_COLOROP_H__
> +#define __AMDGPU_DM_COLOROP_H__
> +
> +extern const u64 amdgpu_dm_supported_degam_tfs;
> +
> +int amdgpu_dm_initialize_default_pipeline(struct drm_plane *plane, struct drm_prop_enum_list *list);
> +
> +#endif /* __AMDGPU_DM_COLOROP_H__*/
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
> index 9a5b184e594f..9a56ade18314 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
> @@ -37,6 +37,7 @@
>   #include "amdgpu_display.h"
>   #include "amdgpu_dm_trace.h"
>   #include "amdgpu_dm_plane.h"
> +#include "amdgpu_dm_colorop.h"
>   #include "gc/gc_11_0_0_offset.h"
>   #include "gc/gc_11_0_0_sh_mask.h"
>   
> @@ -1790,11 +1791,26 @@ static int
>   dm_plane_init_colorops(struct drm_plane *plane)
>   {
>   	struct drm_prop_enum_list pipelines[MAX_COLOR_PIPELINES];
> +	struct drm_device *dev = plane->dev;
> +	struct amdgpu_device *adev = drm_to_adev(dev);
> +	struct dc *dc = adev->dm.dc;
>   	int len = 0;
> +	int ret;
>   
>   	if (plane->type == DRM_PLANE_TYPE_CURSOR)
>   		return 0;
>   
> +	/* initialize pipeline */
> +	if (dc->ctx->dce_version >= DCN_VERSION_3_0) {
Hi Alex,

I think you should skip color pipeline initialization and also doesn't 
expose COLOR_PIPELINE property in DCN older than 3.
It means returning earlier as done for cursor planes, instead of only 
exposing the "Bypass" color pipeline.
So those HW versions can still use current DRM color properties that is 
not exposed if COLOR_PIPELINE is.
> +		ret = amdgpu_dm_initialize_default_pipeline(plane, &(pipelines[len]));
> +		if (ret) {
> +			drm_err(plane->dev, "Failed to create color pipeline for plane %d: %d\n",
> +				plane->base.id, ret);
> +			return ret;
> +		}
> +		len++;
> +	}
> +
>   	/* Create COLOR_PIPELINE property and attach */
>   	drm_plane_create_color_pipeline_property(plane, pipelines, len);
>   



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