| Message ID | 20230824034705.755243-1-ankit.k.nautiyal@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] drm/display/dp: Default 8 bpc support when DSC is supported | expand |
On Thu, 24 Aug 2023, Ankit Nautiyal <ankit.k.nautiyal@intel.com> wrote: > As per DP v1.4, a DP DSC Sink device shall support 8bpc in DPCD 6Ah. > Apparently some panels that do support DSC, are not setting the bit for > 8bpc. > > So always assume 8bpc support by DSC decoder, when DSC is claimed to be > supported. > > v2: Use helper to check dsc support. (Ankit) > > Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com> > --- > drivers/gpu/drm/display/drm_dp_helper.c | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c > index e6a78fd32380..309fc10cde78 100644 > --- a/drivers/gpu/drm/display/drm_dp_helper.c > +++ b/drivers/gpu/drm/display/drm_dp_helper.c > @@ -2447,14 +2447,19 @@ int drm_dp_dsc_sink_supported_input_bpcs(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_S > u8 dsc_bpc[3]) > { > int num_bpc = 0; > + > + if(!drm_dp_sink_supports_dsc(dsc_dpcd)) ^ Missing space. > + return 0; > + > u8 color_depth = dsc_dpcd[DP_DSC_DEC_COLOR_DEPTH_CAP - DP_DSC_SUPPORT]; All declarations should be before code. > > if (color_depth & DP_DSC_12_BPC) > dsc_bpc[num_bpc++] = 12; > if (color_depth & DP_DSC_10_BPC) > dsc_bpc[num_bpc++] = 10; > - if (color_depth & DP_DSC_8_BPC) > - dsc_bpc[num_bpc++] = 8; > + > + /* A DP DSC Sink devices shall support 8 bpc. */ Mixed singular and plural, a ... devices. > + dsc_bpc[num_bpc++] = 8; > > return num_bpc; > }
Thanks Jani for the corrections and suggestions. I agree to them and will fix them in next version. Now that I see the commit subject line also should have been "Assume 8 bpc support when DSC is supported", will change that too. Regards, Ankit On 8/24/2023 3:15 PM, Jani Nikula wrote: > On Thu, 24 Aug 2023, Ankit Nautiyal <ankit.k.nautiyal@intel.com> wrote: >> As per DP v1.4, a DP DSC Sink device shall support 8bpc in DPCD 6Ah. >> Apparently some panels that do support DSC, are not setting the bit for >> 8bpc. >> >> So always assume 8bpc support by DSC decoder, when DSC is claimed to be >> supported. >> >> v2: Use helper to check dsc support. (Ankit) >> >> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com> >> --- >> drivers/gpu/drm/display/drm_dp_helper.c | 9 +++++++-- >> 1 file changed, 7 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c >> index e6a78fd32380..309fc10cde78 100644 >> --- a/drivers/gpu/drm/display/drm_dp_helper.c >> +++ b/drivers/gpu/drm/display/drm_dp_helper.c >> @@ -2447,14 +2447,19 @@ int drm_dp_dsc_sink_supported_input_bpcs(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_S >> u8 dsc_bpc[3]) >> { >> int num_bpc = 0; >> + >> + if(!drm_dp_sink_supports_dsc(dsc_dpcd)) > ^ > > Missing space. > >> + return 0; >> + >> u8 color_depth = dsc_dpcd[DP_DSC_DEC_COLOR_DEPTH_CAP - DP_DSC_SUPPORT]; > All declarations should be before code. > >> >> if (color_depth & DP_DSC_12_BPC) >> dsc_bpc[num_bpc++] = 12; >> if (color_depth & DP_DSC_10_BPC) >> dsc_bpc[num_bpc++] = 10; >> - if (color_depth & DP_DSC_8_BPC) >> - dsc_bpc[num_bpc++] = 8; >> + >> + /* A DP DSC Sink devices shall support 8 bpc. */ > Mixed singular and plural, a ... devices. > >> + dsc_bpc[num_bpc++] = 8; >> >> return num_bpc; >> }
diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c index e6a78fd32380..309fc10cde78 100644 --- a/drivers/gpu/drm/display/drm_dp_helper.c +++ b/drivers/gpu/drm/display/drm_dp_helper.c @@ -2447,14 +2447,19 @@ int drm_dp_dsc_sink_supported_input_bpcs(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_S u8 dsc_bpc[3]) { int num_bpc = 0; + + if(!drm_dp_sink_supports_dsc(dsc_dpcd)) + return 0; + u8 color_depth = dsc_dpcd[DP_DSC_DEC_COLOR_DEPTH_CAP - DP_DSC_SUPPORT]; if (color_depth & DP_DSC_12_BPC) dsc_bpc[num_bpc++] = 12; if (color_depth & DP_DSC_10_BPC) dsc_bpc[num_bpc++] = 10; - if (color_depth & DP_DSC_8_BPC) - dsc_bpc[num_bpc++] = 8; + + /* A DP DSC Sink devices shall support 8 bpc. */ + dsc_bpc[num_bpc++] = 8; return num_bpc; }
As per DP v1.4, a DP DSC Sink device shall support 8bpc in DPCD 6Ah. Apparently some panels that do support DSC, are not setting the bit for 8bpc. So always assume 8bpc support by DSC decoder, when DSC is claimed to be supported. v2: Use helper to check dsc support. (Ankit) Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com> --- drivers/gpu/drm/display/drm_dp_helper.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)