[PATCH v3 09/32] drm/amd/display: add plane 3D LUT driver-specific properties

Melissa Wen mwen at igalia.com
Tue Oct 3 16:17:40 UTC 2023


On 09/27, Harry Wentland wrote:
> 
> 
> On 2023-09-25 15:49, Melissa Wen wrote:
> > Add 3D LUT property for plane color transformations using a 3D lookup
> > table. 3D LUT allows for highly accurate and complex color
> > transformations and is suitable to adjust the balance between color
> > channels. It's also more complex to manage and require more
> > computational resources. Since a 3D LUT has a limited number of entries
> > in each dimension we want to use them in an optimal fashion. This means
> > using the 3D LUT in a colorspace that is optimized for human vision,
> > such as sRGB, PQ, or another non-linear space. Therefore, userpace may
> > need one 1D LUT (shaper) before it to delinearize content and another 1D
> > LUT after 3D LUT (blend) to linearize content again for blending. The
> > next patches add these 1D LUTs to the plane color mgmt pipeline.
> > 
> > v3:
> > - improve commit message about 3D LUT
> > - describe the 3D LUT entries and size (Harry)
> > 
> > Signed-off-by: Melissa Wen <mwen at igalia.com>
> > ---
> >  drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h      | 17 ++++++++++++++
> >  .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h |  9 ++++++++
> >  .../amd/display/amdgpu_dm/amdgpu_dm_color.c   | 14 +++++++++++
> >  .../amd/display/amdgpu_dm/amdgpu_dm_plane.c   | 23 +++++++++++++++++++
> >  4 files changed, 63 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
> > index 66bae0eed80c..1b5f25989f7f 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
> > @@ -363,6 +363,23 @@ struct amdgpu_mode_info {
> >  	 * @plane_hdr_mult_property:
> >  	 */
> >  	struct drm_property *plane_hdr_mult_property;
> > +	/**
> > +	 * @plane_lut3d_property: Plane property for color transformation using
> > +	 * a 3D LUT (pre-blending), a three-dimensional array where each
> > +	 * element is an RGB triplet. Each dimension has a size of the cubed
> > +	 * root of lut3d_size. The array contains samples from the approximated
> > +	 * function. On AMD, values between samples are estimated by
> > +	 * tetrahedral interpolation. The array is accessed with three indices,
> > +	 * one for each input dimension (color channel), blue being the
> > +	 * outermost dimension, red the innermost.
> > +	 */
> > +	struct drm_property *plane_lut3d_property;
> > +	/**
> > +	 * @plane_degamma_lut_size_property: Plane property to define the max
> > +	 * size of 3D LUT as supported by the driver (read-only). The max size
> > +	 * is the max size of one dimension cubed.
> > +	 */
> 
> I've been thinking about this some more and don't particulary
> like that we're reporting the size as the dimension cubed, e.g.,
> 4913 (17^3) instead of 17. This works for an AMD private API
> (and I'm okay with keeping it as-is if changing it is a lot of
> effort at this point) but in a generic API it would be a source
> of bugs or undefined behavior if a driver mistakenly reported
> a size that doesn't have an even cubed root.
> 
> Reporting the size of a single dimension (e.g., 17 in the case
> of the current AMD driver) would be clearer.
> 
> Could we still change that?

I understand your points, makes sense. I'll send a version that fits the
single-dimension size.

Thanks for the suggestion.

Melissa

> 
> Harry
> 
> 
> > +	struct drm_property *plane_lut3d_size_property;
> >  };
> >  
> >  #define AMDGPU_MAX_BL_LEVEL 0xFF
> > diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
> > index 7ca594c7dfbe..dbd36fc24eca 100644
> > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
> > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
> > @@ -773,6 +773,11 @@ struct dm_plane_state {
> >  	 * S31.32 sign-magnitude.
> >  	 */
> >  	__u64 hdr_mult;
> > +	/**
> > +	 * @lut3d: 3D lookup table blob. The blob (if not NULL) is an array of
> > +	 * &struct drm_color_lut.
> > +	 */
> > +	struct drm_property_blob *lut3d;
> >  };
> >  
> >  struct dm_crtc_state {
> > @@ -858,6 +863,10 @@ void amdgpu_dm_update_freesync_caps(struct drm_connector *connector,
> >  
> >  void amdgpu_dm_trigger_timing_sync(struct drm_device *dev);
> >  
> > +/* 3D LUT max size is 17x17x17 */
> > +#define MAX_COLOR_3DLUT_ENTRIES 4913
> > +#define MAX_COLOR_3DLUT_BITDEPTH 12
> > +/* 1D LUT size */
> >  #define MAX_COLOR_LUT_ENTRIES 4096
> >  /* Legacy gamm LUT users such as X doesn't like large LUT sizes */
> >  #define MAX_COLOR_LEGACY_LUT_ENTRIES 256
> > 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 f274909c0c7e..e2f3f2099cac 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
> > @@ -207,6 +207,20 @@ amdgpu_dm_create_color_properties(struct amdgpu_device *adev)
> >  		return -ENOMEM;
> >  	adev->mode_info.plane_hdr_mult_property = prop;
> >  
> > +	prop = drm_property_create(adev_to_drm(adev),
> > +				   DRM_MODE_PROP_BLOB,
> > +				   "AMD_PLANE_LUT3D", 0);
> > +	if (!prop)
> > +		return -ENOMEM;
> > +	adev->mode_info.plane_lut3d_property = prop;
> > +
> > +	prop = drm_property_create_range(adev_to_drm(adev),
> > +					 DRM_MODE_PROP_IMMUTABLE,
> > +					 "AMD_PLANE_LUT3D_SIZE", 0, UINT_MAX);
> > +	if (!prop)
> > +		return -ENOMEM;
> > +	adev->mode_info.plane_lut3d_size_property = prop;
> > +
> >  	return 0;
> >  }
> >  #endif
> > 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 b66da6b76f5c..56f9109ecf60 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
> > @@ -1361,6 +1361,8 @@ dm_drm_plane_duplicate_state(struct drm_plane *plane)
> >  
> >  	if (dm_plane_state->degamma_lut)
> >  		drm_property_blob_get(dm_plane_state->degamma_lut);
> > +	if (dm_plane_state->lut3d)
> > +		drm_property_blob_get(dm_plane_state->lut3d);
> >  
> >  	dm_plane_state->degamma_tf = old_dm_plane_state->degamma_tf;
> >  	dm_plane_state->hdr_mult = old_dm_plane_state->hdr_mult;
> > @@ -1434,6 +1436,8 @@ static void dm_drm_plane_destroy_state(struct drm_plane *plane,
> >  
> >  	if (dm_plane_state->degamma_lut)
> >  		drm_property_blob_put(dm_plane_state->degamma_lut);
> > +	if (dm_plane_state->lut3d)
> > +		drm_property_blob_put(dm_plane_state->lut3d);
> >  
> >  	if (dm_plane_state->dc_state)
> >  		dc_plane_state_release(dm_plane_state->dc_state);
> > @@ -1464,6 +1468,14 @@ dm_atomic_plane_attach_color_mgmt_properties(struct amdgpu_display_manager *dm,
> >  	drm_object_attach_property(&plane->base,
> >  				   dm->adev->mode_info.plane_hdr_mult_property,
> >  				   AMDGPU_HDR_MULT_DEFAULT);
> > +
> > +	if (dpp_color_caps.hw_3d_lut) {
> > +		drm_object_attach_property(&plane->base,
> > +					   mode_info.plane_lut3d_property, 0);
> > +		drm_object_attach_property(&plane->base,
> > +					   mode_info.plane_lut3d_size_property,
> > +					   MAX_COLOR_3DLUT_ENTRIES);
> > +	}
> >  }
> >  
> >  static int
> > @@ -1495,6 +1507,14 @@ dm_atomic_plane_set_property(struct drm_plane *plane,
> >  			dm_plane_state->hdr_mult = val;
> >  			dm_plane_state->base.color_mgmt_changed = 1;
> >  		}
> > +	} else if (property == adev->mode_info.plane_lut3d_property) {
> > +		ret = drm_property_replace_blob_from_id(plane->dev,
> > +							&dm_plane_state->lut3d,
> > +							val, -1,
> > +							sizeof(struct drm_color_lut),
> > +							&replaced);
> > +		dm_plane_state->base.color_mgmt_changed |= replaced;
> > +		return ret;
> >  	} else {
> >  		drm_dbg_atomic(plane->dev,
> >  			       "[PLANE:%d:%s] unknown property [PROP:%d:%s]]\n",
> > @@ -1522,6 +1542,9 @@ dm_atomic_plane_get_property(struct drm_plane *plane,
> >  		*val = dm_plane_state->degamma_tf;
> >  	} else if (property == adev->mode_info.plane_hdr_mult_property) {
> >  		*val = dm_plane_state->hdr_mult;
> > +	} else 	if (property == adev->mode_info.plane_lut3d_property) {
> > +		*val = (dm_plane_state->lut3d) ?
> > +			dm_plane_state->lut3d->base.id : 0;
> >  	} else {
> >  		return -EINVAL;
> >  	}
> 


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