From 5488dc16fde74595a40c5d20ae52d978313f0b4e Mon Sep 17 00:00:00 2001 From: Lionel Landwerlin Date: Fri, 26 Feb 2016 17:05:00 +0000 Subject: drm: introduce pipe color correction properties Patch based on a previous series by Shashank Sharma. This introduces optional properties to enable color correction at the pipe level. It relies on 3 transformations applied to every pixels displayed. First a lookup into a degamma table, then a multiplication of the rgb components by a 3x3 matrix and finally another lookup into a gamma table. The following properties can be added to a pipe : - DEGAMMA_LUT : blob containing degamma LUT - DEGAMMA_LUT_SIZE : number of elements in DEGAMMA_LUT - CTM : transformation matrix applied after the degamma LUT - GAMMA_LUT : blob containing gamma LUT - GAMMA_LUT_SIZE : number of elements in GAMMA_LUT DEGAMMA_LUT_SIZE and GAMMA_LUT_SIZE are read only properties, set by the driver to tell userspace applications what sizes should be the lookup tables in DEGAMMA_LUT and GAMMA_LUT. A helper is also provided so legacy gamma correction is redirected through these new properties. v2: Register LUT size properties as range v3: Fix round in drm_color_lut_get_value() helper More docs on how degamma/gamma properties are used v4: Update contributors v5: Rename CTM_MATRIX property to CTM (Doh!) Add legacy gamma_set atomic helper Describe CTM/LUT acronyms in the kernel doc v6: Fix missing blob unref in drm_atomic_helper_crtc_reset Signed-off-by: Shashank Sharma Signed-off-by: Kumar, Kiran S Signed-off-by: Kausal Malladi Signed-off-by: Lionel Landwerlin Reviewed-by: Matt Roper Acked-by: Rob Bradford [danvet: CrOS maintainers are also happy with the userspacde side: https://codereview.chromium.org/1182063002/ ] Reviewed-by: Daniel Stone Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/1456506302-640-4-git-send-email-lionel.g.landwerlin@intel.com --- Documentation/DocBook/gpu.tmpl | 59 ++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 57 insertions(+), 2 deletions(-) (limited to 'Documentation/DocBook') diff --git a/Documentation/DocBook/gpu.tmpl b/Documentation/DocBook/gpu.tmpl index fe6b36a2fd98..1692c4dd5487 100644 --- a/Documentation/DocBook/gpu.tmpl +++ b/Documentation/DocBook/gpu.tmpl @@ -1816,7 +1816,7 @@ void intel_crt_init(struct drm_device *dev) Description/Restrictions - DRM + DRM Generic “rotation” BITMASK @@ -2068,7 +2068,7 @@ void intel_crt_init(struct drm_device *dev) property to suggest an Y offset for a connector - Optional + Optional “scaling mode” ENUM { "None", "Full", "Center", "Full aspect" } @@ -2092,6 +2092,61 @@ void intel_crt_init(struct drm_device *dev) TBD + “DEGAMMA_LUT” + BLOB + 0 + CRTC + DRM property to set the degamma lookup table + (LUT) mapping pixel data from the framebuffer before it is + given to the transformation matrix. The data is an interpreted + as an array of struct drm_color_lut elements. Hardware might + choose not to use the full precision of the LUT elements nor + use all the elements of the LUT (for example the hardware + might choose to interpolate between LUT[0] and LUT[4]). + + + “DEGAMMA_LUT_SIZE” + RANGE | IMMUTABLE + Min=0, Max=UINT_MAX + CRTC + DRM property to gives the size of the lookup + table to be set on the DEGAMMA_LUT property (the size depends + on the underlying hardware). + + + “CTM” + BLOB + 0 + CRTC + DRM property to set the current + transformation matrix (CTM) apply to pixel data after the + lookup through the degamma LUT and before the lookup through + the gamma LUT. The data is an interpreted as a struct + drm_color_ctm. + + + “GAMMA_LUT” + BLOB + 0 + CRTC + DRM property to set the gamma lookup table + (LUT) mapping pixel data after to the transformation matrix to + data sent to the connector. The data is an interpreted as an + array of struct drm_color_lut elements. Hardware might choose + not to use the full precision of the LUT elements nor use all + the elements of the LUT (for example the hardware might choose + to interpolate between LUT[0] and LUT[4]). + + + “GAMMA_LUT_SIZE” + RANGE | IMMUTABLE + Min=0, Max=UINT_MAX + CRTC + DRM property to gives the size of the lookup + table to be set on the GAMMA_LUT property (the size depends on + the underlying hardware). + + i915 Generic "Broadcast RGB" -- cgit v1.2.3