On Tue, Dec 15, 2020 at 10:42:19PM +0000, Andres Calderon Jaramillo wrote: > From: Andres Calderon Jaramillo <andrescj@xxxxxxxxxxxx> > > Prevent the ICL HDR plane pipeline from performing YUV color range > correction twice when the input is in limited range. This is done by > removing the limited-range code from icl_program_input_csc(). > > Before this patch the following could happen: user space gives us a YUV > buffer in limited range; per the pipeline in [1], the plane would first > go through a "YUV Range correct" stage that expands the range; the plane > would then go through the "Input CSC" stage which would also expand the > range because icl_program_input_csc() would use a matrix and an offset > that assume limited-range input; this would ultimately cause dark and > light colors to appear darker and lighter than they should respectively. > > This is an issue because if a buffer switches between being scanned out > and being composited with the GPU, the user will see a color difference. > If this switching happens quickly and frequently, the user will perceive > this as a flickering. > > [1] https://01.org/sites/default/files/documentation/intel-gfx-prm-osrc-icllp-vol12-displayengine_0.pdf#page=281 > > Signed-off-by: Andres Calderon Jaramillo <andrescj@xxxxxxxxxxxx> Thanks. Slapped a cc:stable on this and pushed. > --- > Changelog since v1: > - Don't skip the YUV range correction stage. Instead, use that stage and > modify icl_program_input_csc() to always assume full-range input. > > drivers/gpu/drm/i915/display/intel_display.c | 2 + > drivers/gpu/drm/i915/display/intel_sprite.c | 65 +++----------------- > 2 files changed, 12 insertions(+), 55 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c > index 761be8deaa9b..8fb9b4f8c1df 100644 > --- a/drivers/gpu/drm/i915/display/intel_display.c > +++ b/drivers/gpu/drm/i915/display/intel_display.c > @@ -4811,6 +4811,8 @@ u32 glk_plane_color_ctl(const struct intel_crtc_state *crtc_state, > plane_color_ctl |= PLANE_COLOR_YUV_RANGE_CORRECTION_DISABLE; > } else if (fb->format->is_yuv) { > plane_color_ctl |= PLANE_COLOR_INPUT_CSC_ENABLE; > + if (plane_state->hw.color_range == DRM_COLOR_YCBCR_FULL_RANGE) > + plane_color_ctl |= PLANE_COLOR_YUV_RANGE_CORRECTION_DISABLE; > } > > return plane_color_ctl; > diff --git a/drivers/gpu/drm/i915/display/intel_sprite.c b/drivers/gpu/drm/i915/display/intel_sprite.c > index b7e208816074..121e1b5120fd 100644 > --- a/drivers/gpu/drm/i915/display/intel_sprite.c > +++ b/drivers/gpu/drm/i915/display/intel_sprite.c > @@ -633,13 +633,19 @@ skl_program_scaler(struct intel_plane *plane, > > /* Preoffset values for YUV to RGB Conversion */ > #define PREOFF_YUV_TO_RGB_HI 0x1800 > -#define PREOFF_YUV_TO_RGB_ME 0x1F00 > +#define PREOFF_YUV_TO_RGB_ME 0x0000 > #define PREOFF_YUV_TO_RGB_LO 0x1800 > > #define ROFF(x) (((x) & 0xffff) << 16) > #define GOFF(x) (((x) & 0xffff) << 0) > #define BOFF(x) (((x) & 0xffff) << 16) > > +/* > + * Programs the input color space conversion stage for ICL HDR planes. > + * Note that it is assumed that this stage always happens after YUV > + * range correction. Thus, the input to this stage is assumed to be > + * in full-range YCbCr. > + */ > static void > icl_program_input_csc(struct intel_plane *plane, > const struct intel_crtc_state *crtc_state, > @@ -687,52 +693,7 @@ icl_program_input_csc(struct intel_plane *plane, > 0x0, 0x7800, 0x7F10, > }, > }; > - > - /* Matrix for Limited Range to Full Range Conversion */ > - static const u16 input_csc_matrix_lr[][9] = { > - /* > - * BT.601 Limted range YCbCr -> full range RGB > - * The matrix required is : > - * [1.164384, 0.000, 1.596027, > - * 1.164384, -0.39175, -0.812813, > - * 1.164384, 2.017232, 0.0000] > - */ > - [DRM_COLOR_YCBCR_BT601] = { > - 0x7CC8, 0x7950, 0x0, > - 0x8D00, 0x7950, 0x9C88, > - 0x0, 0x7950, 0x6810, > - }, > - /* > - * BT.709 Limited range YCbCr -> full range RGB > - * The matrix required is : > - * [1.164384, 0.000, 1.792741, > - * 1.164384, -0.213249, -0.532909, > - * 1.164384, 2.112402, 0.0000] > - */ > - [DRM_COLOR_YCBCR_BT709] = { > - 0x7E58, 0x7950, 0x0, > - 0x8888, 0x7950, 0xADA8, > - 0x0, 0x7950, 0x6870, > - }, > - /* > - * BT.2020 Limited range YCbCr -> full range RGB > - * The matrix required is : > - * [1.164, 0.000, 1.678, > - * 1.164, -0.1873, -0.6504, > - * 1.164, 2.1417, 0.0000] > - */ > - [DRM_COLOR_YCBCR_BT2020] = { > - 0x7D70, 0x7950, 0x0, > - 0x8A68, 0x7950, 0xAC00, > - 0x0, 0x7950, 0x6890, > - }, > - }; > - const u16 *csc; > - > - if (plane_state->hw.color_range == DRM_COLOR_YCBCR_FULL_RANGE) > - csc = input_csc_matrix[plane_state->hw.color_encoding]; > - else > - csc = input_csc_matrix_lr[plane_state->hw.color_encoding]; > + const u16 *csc = input_csc_matrix[plane_state->hw.color_encoding]; > > intel_de_write_fw(dev_priv, PLANE_INPUT_CSC_COEFF(pipe, plane_id, 0), > ROFF(csc[0]) | GOFF(csc[1])); > @@ -749,14 +710,8 @@ icl_program_input_csc(struct intel_plane *plane, > > intel_de_write_fw(dev_priv, PLANE_INPUT_CSC_PREOFF(pipe, plane_id, 0), > PREOFF_YUV_TO_RGB_HI); > - if (plane_state->hw.color_range == DRM_COLOR_YCBCR_FULL_RANGE) > - intel_de_write_fw(dev_priv, > - PLANE_INPUT_CSC_PREOFF(pipe, plane_id, 1), > - 0); > - else > - intel_de_write_fw(dev_priv, > - PLANE_INPUT_CSC_PREOFF(pipe, plane_id, 1), > - PREOFF_YUV_TO_RGB_ME); > + intel_de_write_fw(dev_priv, PLANE_INPUT_CSC_PREOFF(pipe, plane_id, 1), > + PREOFF_YUV_TO_RGB_ME); > intel_de_write_fw(dev_priv, PLANE_INPUT_CSC_PREOFF(pipe, plane_id, 2), > PREOFF_YUV_TO_RGB_LO); > intel_de_write_fw(dev_priv, > -- > 2.29.2.684.gfbc64c5ab5-goog -- Ville Syrjälä Intel _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
