From: Nikola Cornij Date: Wed, 5 Jun 2019 18:29:47 +0000 (-0400) Subject: drm/amd/display: Set one 4:2:0-related PPS field as recommended by DSC spec X-Git-Tag: v5.3-rc2~20^2^2~25 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=61011e63f87fe5dd0ebff787cd78df4d7d66aec5;p=linux.git drm/amd/display: Set one 4:2:0-related PPS field as recommended by DSC spec [why] 'second_line_offset_adj' was mistakenly left at zero, even though DSC spec v1.2a recommends setting this field to 512 for 4:2:0. [how] Set 'second_line_offset_adj' to 512 for 4:2:0 and leave at zero otherwise Signed-off-by: Nikola Cornij Reviewed-by: Eric Bernstein Acked-by: Leo Li Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/amd/display/dc/dsc/drm_dsc_dc.c b/drivers/gpu/drm/amd/display/dc/dsc/drm_dsc_dc.c index 67089765780b..340ef4d41ebd 100644 --- a/drivers/gpu/drm/amd/display/dc/dsc/drm_dsc_dc.c +++ b/drivers/gpu/drm/amd/display/dc/dsc/drm_dsc_dc.c @@ -377,6 +377,12 @@ int drm_dsc_compute_rc_parameters(struct drm_dsc_config *vdsc_cfg) vdsc_cfg->rc_bits = (hrd_delay * vdsc_cfg->bits_per_pixel) / 16; vdsc_cfg->initial_dec_delay = hrd_delay - vdsc_cfg->initial_xmit_delay; + /* As per DSC spec v1.2a recommendation: */ + if (vdsc_cfg->native_420) + vdsc_cfg->second_line_offset_adj = 512; + else + vdsc_cfg->second_line_offset_adj = 0; + return 0; } EXPORT_SYMBOL(drm_dsc_compute_rc_parameters);