Re: [PATCH v7 11/25] drm/i915: Register color correction capabilities

Bish, Jim
2015-10-21T23:19:10Z

On Tue, 2015-10-20 at 18:04 +0530, Shashank Sharma wrote:
> From DRM color management:
> ============================
> DRM color manager supports these color properties:
> 1. "ctm": Color transformation matrix property, where a
> color transformation matrix of 9 correction values gets
> applied as correction.
> 2. "palette_before_ctm": for corrections which get applied
> beore color transformation matrix correction.
> 3. "palette_after_ctm": for corrections which get applied
> after color transformation matrix correction.
>
> These color correction capabilities may differ per platform,
> supporting
> various different no. of correction coefficients. So DRM color
> manager
> support few properties using which a user space can query the
> platform's
> capability, and prepare color correction accordingly.
> These query properties are:
> 1. cm_coeff_after_ctm_property
> 2. cm_coeff_before_ctm_property
> (CTM is fix to 9 coefficients across industry)
>
> Now, Intel color manager registers:
> ======================================
> 1. Gamma correction property as "palette_after_ctm" property
> 2. Degamma correction capability as "palette_bafore_ctm" property
> capability as "palette_after_ctm" DRM color property hook.
> 3. CSC as "ctm" property.
>
> So finally, This patch does the following:
> 1. Add a function which loads the platform's color correction
> capabilities in the cm_crtc_palette_capabilities_property
> structure.
> 2. Attaches the cm_crtc_palette_capabilities_property to every CRTC
> getting initiaized.
> 3. Adds two new parameters "num_samples_after_ctm" and
> "num_samples_before_ctm" in intel_device_info as gamma and
> degamma coefficients vary per platform basis.
>
> Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
> Signed-off-by: Kausal Malladi <kausalmalladi@gmail.com>
> ---
> drivers/gpu/drm/i915/i915_drv.h | 2 ++
> drivers/gpu/drm/i915/intel_color_manager.c | 31
> ++++++++++++++++++++++++++++++
> 2 files changed, 33 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/i915_drv.h
> b/drivers/gpu/drm/i915/i915_drv.h
> index 8afda45..613bee2 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -789,6 +789,8 @@ struct intel_device_info {
> u8 num_sprites[I915_MAX_PIPES];
> u8 gen;
> u8 ring_mask; /* Rings supported by the HW */
> + u16 num_samples_after_ctm;
> + u16 num_samples_before_ctm;
thought we agreed last week that num_samples was going to be
removed. May be ok to handle in a later patch unless
someone has strong objection.

Jim
> DEV_INFO_FOR_EACH_FLAG(DEFINE_FLAG, SEP_SEMICOLON);
> /* Register offsets for the various display pipes and transcoders
> */
> int pipe_offsets[I915_MAX_TRANSCODERS];
> diff --git a/drivers/gpu/drm/i915/intel_color_manager.c
> b/drivers/gpu/drm/i915/intel_color_manager.c
> index b03ee94..334bfff 100644
> --- a/drivers/gpu/drm/i915/intel_color_manager.c
> +++ b/drivers/gpu/drm/i915/intel_color_manager.c
> @@ -30,4 +30,35 @@
> void intel_attach_color_properties_to_crtc(struct drm_device *dev,
> struct drm_crtc *crtc)
> {
> + struct drm_mode_config *config = &dev->mode_config;
> + struct drm_mode_object *mode_obj = &crtc->base;
> +
> + /*
> + * Register:
> + * =========
> + * Gamma correction as palette_after_ctm property
> + * Degamma correction as palette_before_ctm property
> + *
> + * Load:
> + * =====
> + * no. of coefficients supported on this platform for gamma
> + * and degamma with the query properties. A user
> + * space agent should read these query property, and prepare
> + * the color correction values accordingly. Its expected from the
> + * driver to load the right number of coefficients during the init
> + * phase.
> + */
> + if (config->cm_coeff_after_ctm_property) {
> + drm_object_attach_property(mode_obj,
> + config->cm_coeff_after_ctm_property,
> + INTEL_INFO(dev)->num_samples_after_ctm);
> + DRM_DEBUG_DRIVER("Gamma query property initialized\n");
> + }
> +
> + if (config->cm_coeff_before_ctm_property) {
> + drm_object_attach_property(mode_obj,
> + config->cm_coeff_before_ctm_property,
> + INTEL_INFO(dev)->num_samples_before_ctm);
> + DRM_DEBUG_DRIVER("Degamma query property initialized\n");
> + }
> }