On 5/24/2023 8:25 AM, Suraj Kandpal wrote:
Move rc_param calculation for native_420 into calculate_rc_parameter.
second_line_bpg_offset and second_line_offset_adj are both rc params
and it would be better to have these calculated where all the other
rc parameters are calculated.
--v2
-Add the reason for commit in commit message [Jani]
Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
Cc: Ankit Nautiyal <ankit.k.nautiyal@xxxxxxxxx>
Signed-off-by: Suraj Kandpal <suraj.kandpal@xxxxxxxxx>
---
drivers/gpu/drm/i915/display/intel_vdsc.c | 28 +++++++++++++----------
1 file changed, 16 insertions(+), 12 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c b/drivers/gpu/drm/i915/display/intel_vdsc.c
index bd9116d2cd76..c64a38363e02 100644
--- a/drivers/gpu/drm/i915/display/intel_vdsc.c
+++ b/drivers/gpu/drm/i915/display/intel_vdsc.c
@@ -78,6 +78,22 @@ calculate_rc_params(struct drm_dsc_config *vdsc_cfg)
else
vdsc_cfg->first_line_bpg_offset = 2 * (vdsc_cfg->slice_height - 1);
+ /* According to DSC 1.2 specs in Section 4.1 if native_420 is set:
+ * -second_line_bpg_offset is 12 in general and equal to 2*(slice_height-1) if slice
+ * height < 8.
+ * -second_line_offset_adj is 512 as shown by emperical values to yeild best chroma
+ * preservation in second line.
+ */
+ if (vdsc_cfg->native_420) {
+ if (vdsc_cfg->slice_height >= 8)
+ vdsc_cfg->second_line_bpg_offset = 12;
+ else
+ vdsc_cfg->second_line_bpg_offset =
+ 2 * (vdsc_cfg->slice_height - 1);
+
+ vdsc_cfg->second_line_offset_adj = 512;
+ }
+
/* Our hw supports only 444 modes as of today */
if (bpp >= 12)
vdsc_cfg->initial_offset = 2048;
@@ -192,24 +208,12 @@ int intel_dsc_compute_params(struct intel_crtc_state *pipe_config)
/*
* According to DSC 1.2 specs in Section 4.1 if native_420 is set:
* -We need to double the current bpp.
- * -second_line_bpg_offset is 12 in general and equal to 2*(slice_height-1) if slice
- * height < 8.
- * -second_line_offset_adj is 512 as shown by emperical values to yeild best chroma
- * preservation in second line.
* -nsl_bpg_offset is calculated as second_line_offset/slice_height -1 then rounded
* up to 16 fractional bits, we left shift second line offset by 11 to preserve 11
* fractional bits.
*/
if (vdsc_cfg->native_420) {
vdsc_cfg->bits_per_pixel <<= 1;
-
- if (vdsc_cfg->slice_height >= 8)
- vdsc_cfg->second_line_bpg_offset = 12;
- else
- vdsc_cfg->second_line_bpg_offset =
- 2 * (vdsc_cfg->slice_height - 1);
-
- vdsc_cfg->second_line_offset_adj = 512;
vdsc_cfg->nsl_bpg_offset = DIV_ROUND_UP(vdsc_cfg->second_line_bpg_offset << 11,
This seems wrong. We have removed code to set second_line_bpg_offset
from here to the function calculate_rc_params, which is called later,
but nsl_bpg_offset is using the second_line_bpg_offset.
So if we want to move the two params in calculate_rc_params, then lets
call it earlier, before these values get used.
Regards,
Ankit
vdsc_cfg->slice_height - 1);
}
