Re: [PATCH 1/2] drm/display/dp: Default 8 bpc support when DSC is supported
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 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
---
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;
}
Re: [PATCH 1/2] drm/display/dp: Default 8 bpc support when DSC is supported
On Thu, 24 Aug 2023, Ankit Nautiyal 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
> ---
> 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;
> }
--
Jani Nikula, Intel Open Source Graphics Center
[PATCH 1/2] drm/display/dp: Default 8 bpc support when DSC is supported
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
---
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))
+ 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;
}
--
2.40.1
Re: [PATCH 1/2] drm/display/dp: Default 8 bpc support when DSC is supported
Hi Ankit,
kernel test robot noticed the following build warnings:
[auto build test WARNING on drm-tip/drm-tip]
[also build test WARNING on linus/master v6.5-rc7 next-20230823]
[cannot apply to drm-intel/for-linux-next drm-intel/for-linux-next-fixes
drm-misc/drm-misc-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url:
https://github.com/intel-lab-lkp/linux/commits/Ankit-Nautiyal/drm-display-dp-Default-8-bpc-support-when-DSC-is-supported/20230823-195946
base: git://anongit.freedesktop.org/drm/drm-tip drm-tip
patch link:
https://lore.kernel.org/r/20230823115425.715644-2-ankit.k.nautiyal%40intel.com
patch subject: [PATCH 1/2] drm/display/dp: Default 8 bpc support when DSC is
supported
config: i386-randconfig-r036-20230823
(https://download.01.org/0day-ci/archive/20230824/202308240007.1eds9xsl-...@intel.com/config)
compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git
ae42196bc493ffe877a7e3dff8be32035dea4d07)
reproduce:
(https://download.01.org/0day-ci/archive/20230824/202308240007.1eds9xsl-...@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot
| Closes:
https://lore.kernel.org/oe-kbuild-all/202308240007.1eds9xsl-...@intel.com/
All warnings (new ones prefixed by >>):
>> drivers/gpu/drm/display/drm_dp_helper.c:2451:6: warning: logical not is only
>> applied to the left hand side of this bitwise operator
>> [-Wlogical-not-parentheses]
if (!dsc_dpcd[DP_DSC_SUPPORT] & DP_DSC_DECOMPRESSION_IS_SUPPORTED)
^ ~
drivers/gpu/drm/display/drm_dp_helper.c:2451:6: note: add parentheses after
the '!' to evaluate the bitwise operator first
if (!dsc_dpcd[DP_DSC_SUPPORT] & DP_DSC_DECOMPRESSION_IS_SUPPORTED)
^
( )
drivers/gpu/drm/display/drm_dp_helper.c:2451:6: note: add parentheses around
left hand side expression to silence this warning
if (!dsc_dpcd[DP_DSC_SUPPORT] & DP_DSC_DECOMPRESSION_IS_SUPPORTED)
^
()
1 warning generated.
vim +2451 drivers/gpu/drm/display/drm_dp_helper.c
2428
2429 /**
2430 * drm_dp_dsc_sink_supported_input_bpcs() - Get all the input bits per
component
2431 * values supported by the DSC sink.
2432 * @dsc_dpcd: DSC capabilities from DPCD
2433 * @dsc_bpc: An array to be filled by this helper with supported
2434 * input bpcs.
2435 *
2436 * Read the DSC DPCD from the sink device to parse the supported bits
per
2437 * component values. This is used to populate the DSC parameters
2438 * in the drm_dsc_config by the driver.
2439 * Driver creates an infoframe using these parameters to populate
2440 * drm_dsc_pps_infoframe. These are sent to the sink using DSC
2441 * infoframe using the helper function drm_dsc_pps_infoframe_pack()
2442 *
2443 * Returns:
2444 * Number of input BPC values parsed from the DPCD
2445 */
2446 int drm_dp_dsc_sink_supported_input_bpcs(const u8
dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE],
2447 u8 dsc_bpc[3])
2448 {
2449 int num_bpc = 0;
2450
> 2451 if (!dsc_dpcd[DP_DSC_SUPPORT] &
> DP_DSC_DECOMPRESSION_IS_SUPPORTED)
2452 return 0;
2453
2454 u8 color_depth = dsc_dpcd[DP_DSC_DEC_COLOR_DEPTH_CAP -
DP_DSC_SUPPORT];
2455
2456 if (color_depth & DP_DSC_12_BPC)
2457 dsc_bpc[num_bpc++] = 12;
2458 if (color_depth & DP_DSC_10_BPC)
2459 dsc_bpc[num_bpc++] = 10;
2460
2461 /* A DP DSC Sink devices shall support 8 bpc. */
2462 dsc_bpc[num_bpc++] = 8;
2463
2464 return num_bpc;
2465 }
2466 EXPORT_SYMBOL(drm_dp_dsc_sink_supported_input_bpcs);
2467
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
[PATCH 1/2] drm/display/dp: Default 8 bpc support when DSC is supported
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.
Signed-off-by: Ankit Nautiyal
---
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..0aa4ce17420c 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 (!dsc_dpcd[DP_DSC_SUPPORT] & DP_DSC_DECOMPRESSION_IS_SUPPORTED)
+ 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;
}
--
2.40.1
