diff options
| author | Suraj Kandpal <[email protected]> | 2023-08-04 14:07:37 +0530 |
|---|---|---|
| committer | Ankit Nautiyal <[email protected]> | 2023-08-14 10:18:54 +0530 |
| commit | 58554dbf0991da6a2847b3159594f6306bff978b (patch) | |
| tree | 0dc4fd110b8024483e1be27d965581de1fd09de7 | |
| parent | 4bed08d99c681f1564e4a633b33d8a6d0446c706 (diff) | |
drm/i915/vdsc: Fix first_line_bpg_offset calculation
On checking DSC1.1 Errata and DSC 1.2 spec the current formula
we were using was incorrect to calculate first_line_bpg_offset.
The new fixed formula is derived from C model.
--v2
-Use clamp function in linux/minmax.h [Ankit]
--v3
-remove linux/minmax.h header
Signed-off-by: Suraj Kandpal <[email protected]>
Reviewed-by: Ankit Nautiyal <[email protected]>
Signed-off-by: Ankit Nautiyal <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_vdsc.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c b/drivers/gpu/drm/i915/display/intel_vdsc.c index 9d76c2756784..e4c395b4dc46 100644 --- a/drivers/gpu/drm/i915/display/intel_vdsc.c +++ b/drivers/gpu/drm/i915/display/intel_vdsc.c @@ -80,13 +80,19 @@ calculate_rc_params(struct drm_dsc_config *vdsc_cfg) int bpc = vdsc_cfg->bits_per_component; int bpp = vdsc_cfg->bits_per_pixel >> 4; int qp_bpc_modifier = (bpc - 8) * 2; + int uncompressed_bpg_rate; + int first_line_bpg_offset; u32 res, buf_i, bpp_i; if (vdsc_cfg->slice_height >= 8) - vdsc_cfg->first_line_bpg_offset = - 12 + DIV_ROUND_UP((9 * min(34, vdsc_cfg->slice_height - 8)), 100); + first_line_bpg_offset = + 12 + (9 * min(34, vdsc_cfg->slice_height - 8)) / 100; else - vdsc_cfg->first_line_bpg_offset = 2 * (vdsc_cfg->slice_height - 1); + first_line_bpg_offset = 2 * (vdsc_cfg->slice_height - 1); + + uncompressed_bpg_rate = (3 * bpc + (vdsc_cfg->convert_rgb ? 0 : 2)) * 3; + vdsc_cfg->first_line_bpg_offset = clamp(first_line_bpg_offset, 0, + uncompressed_bpg_rate - 3 * bpp); /* * According to DSC 1.2 spec in Section 4.1 if native_420 is set: |