[PATCH] drm/msm/dpu: Adjust CDM_MUX to support CWB PINGPONG

[Abhinav Kumar]

On 3/5/2025 10:44 PM, Dmitry Baryshkov wrote:
> On Wed, Mar 05, 2025 at 07:16:51PM -0800, Jessica Zhang wrote:
>> Similar to WB_MUX, CDM_MUX also needs to be adjusted to support
>> dedicated CWB PINGPONGs
>>
>> Signed-off-by: Jessica Zhang <quic_jesszhan at quicinc.com>
>> ---
>>   drivers/gpu/drm/msm/disp/dpu1/dpu_hw_cdm.c | 4 +++-
>>   1 file changed, 3 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_cdm.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_cdm.c
>> index ae1534c49ae0..3f88c3641d4a 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_cdm.c
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_cdm.c
>> @@ -214,7 +214,9 @@ static void dpu_hw_cdm_bind_pingpong_blk(struct dpu_hw_cdm *ctx, const enum dpu_
>>   	mux_cfg = DPU_REG_READ(c, CDM_MUX);
>>   	mux_cfg &= ~0xf;
>>   
>> -	if (pp)
>> +	if (pp >= PINGPONG_CWB_0)
>> +		mux_cfg |= 0xd;
> 
> Shouldn't it be 0xb for PINGPONG_CWB_2 and 3?
> 

No, this register CDM_MUX can take only 0xd for CWB PPs.

0xb is not listed as a valid value at all.

>> +	else if (pp)
>>   		mux_cfg |= (pp - PINGPONG_0) & 0x7;
>>   	else
>>   		mux_cfg |= 0xf;
>>
>> ---
>> base-commit: 6d3175a72cc07e90f81fb35841048a8a9b5134cb
>> change-id: 20250305-cdm-cwb-mux-fix-69ed5297d4f7
>>
>> Best regards,
>> -- 
>> Jessica Zhang <quic_jesszhan at quicinc.com>
>>
>