[Intel-gfx] [PATCH] drm/i915/display: Bitwise or the conversion colour specifier together

[Nautiyal, Ankit K]

Thanks Chris to catch this.

This definitely should be bitwise Operator, as mentioned by Jani is 
right thing to do.

The PCON which I had access to, had the F/W which was using 303Ch 
(previously proposed) for color conversion capability, instead of what 
is latest mentioned in the spec ie. 83h.

While testing, I had to skip this line of code, and hardcoded to older 
register ie. 303Ch.

I Will get this patch tested and update.


Thanks & Regards,

Ankit


On 12/23/2020 4:21 PM, Jani Nikula wrote:
> On Wed, 23 Dec 2020, Chris Wilson <chris at chris-wilson.co.uk> wrote:
>> drivers/gpu/drm/i915/display/intel_dp.c:6922 intel_dp_update_420() warn: should this be a bitwise op?
>> drivers/gpu/drm/i915/display/intel_dp.c:6922 intel_dp_update_420() warn: should this be a bitwise op?
>> drivers/gpu/drm/i915/display/intel_dp.c:6923 intel_dp_update_420() warn: should this be a bitwise op?
>>
>> Inside drm_dp_downstream_rgb_to_ycbcr_conversion(), that paramter
>> 'color_spc' is used as return port_cap[3] & color_spc, implying that it
>> is indeed a mask and not a boolean value.
> So this one belongs in topic/dp-hdmi-2.1-pcon branch.
>
> Purely based on the context this is the right thing to do, so:
>
> Reviewed-by: Jani Nikula <jani.nikula at intel.com>
>
> Ankit, please test the patch in case it uncovers some other
> issues. It'll impact the RGB to YCbCr conversion.
>
> BR,
> Jani.
>
>
>> Fixes: 522508b665df ("drm/i915/display: Let PCON convert from RGB to YCbCr if it can")
>> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
>> Cc: Uma Shankar <uma.shankar at intel.com>
>> Cc: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
>> Cc: Jani Nikula <jani.nikula at intel.com>
>> ---
>>   drivers/gpu/drm/i915/display/intel_dp.c | 4 ++--
>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
>> index 8b4b2ea52859..157a850a83a7 100644
>> --- a/drivers/gpu/drm/i915/display/intel_dp.c
>> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
>> @@ -6918,8 +6918,8 @@ intel_dp_update_420(struct intel_dp *intel_dp)
>>   							intel_dp->downstream_ports);
>>   	rgb_to_ycbcr = drm_dp_downstream_rgb_to_ycbcr_conversion(intel_dp->dpcd,
>>   								 intel_dp->downstream_ports,
>> -								 DP_DS_HDMI_BT601_RGB_YCBCR_CONV ||
>> -								 DP_DS_HDMI_BT709_RGB_YCBCR_CONV ||
>> +								 DP_DS_HDMI_BT601_RGB_YCBCR_CONV |
>> +								 DP_DS_HDMI_BT709_RGB_YCBCR_CONV |
>>   								 DP_DS_HDMI_BT2020_RGB_YCBCR_CONV);
>>   
>>   	if (INTEL_GEN(i915) >= 11) {