Re: [PATCH v2 02/14] drm/msm/a6xx: Extend UBWC config

[Konrad Dybcio]

On 17.02.2023 21:46, Dmitry Baryshkov wrote:
> On 14/02/2023 19:31, Konrad Dybcio wrote:
>> Port setting min_access_length, ubwc_mode and upper_bit from downstream.
>> Values were validated using downstream device trees for SM8[123]50 and
>> left default (as per downstream) elsewhere.
>>
>> Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
>> ---
>>   drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 29 +++++++++++++++++++--------
>>   1 file changed, 21 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>> index c5f5d0bb3fdc..8855d798bbb3 100644
>> --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>> @@ -786,17 +786,25 @@ static void a6xx_set_cp_protect(struct msm_gpu *gpu)
>>   static void a6xx_set_ubwc_config(struct msm_gpu *gpu)
>>   {
>>       struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
>> -    u32 lower_bit = 2;
>> +    u32 lower_bit = 1;
> 
> Any reason to change the default value here?
> If it is to match chipsets you are adding, it might be worth splitting this change to that patch.
Not really now that I think about it, especially since the
correct default value should be zero:

-- part of msm-4.19 --
bit = adreno_dev->highest_bank_bit ? adreno_dev->highest_bank_bit - 13 : 0;
lower_bit = bit & 0x3;
upper_bit = (bit >> 0x2) & 1;

where adreno_dev->highest_bank_bit is read from the dt property
"qcom,highest-bank-bit"

Anyway, I should be able to verify it for all the SoCs which
we support.

Konrad
> 
>> +    u32 upper_bit = 0;
>>       u32 amsbc = 0;
>>       u32 rgb565_predicator = 0;
>>       u32 uavflagprd_inv = 0;
>> +    u32 min_acc_len = 0;
>> +    u32 ubwc_mode = 0;
>>         /* a618 is using the hw default values */
>>       if (adreno_is_a618(adreno_gpu))
>>           return;
>>   -    if (adreno_is_a640_family(adreno_gpu))
>> +    if (adreno_is_a630(adreno_gpu))
>> +        lower_bit = 2;
>> +
>> +    if (adreno_is_a640_family(adreno_gpu)) {
>>           amsbc = 1;
>> +        lower_bit = 2;
>> +    }
>>         if (adreno_is_a650(adreno_gpu) || adreno_is_a660(adreno_gpu)) {
>>           /* TODO: get ddr type from bootloader and use 2 for LPDDR4 */
>> @@ -807,18 +815,23 @@ static void a6xx_set_ubwc_config(struct msm_gpu *gpu)
>>       }
>>         if (adreno_is_7c3(adreno_gpu)) {
>> -        lower_bit = 1;
>>           amsbc = 1;
>>           rgb565_predicator = 1;
>>           uavflagprd_inv = 2;
>>       }
>>         gpu_write(gpu, REG_A6XX_RB_NC_MODE_CNTL,
>> -        rgb565_predicator << 11 | amsbc << 4 | lower_bit << 1);
>> -    gpu_write(gpu, REG_A6XX_TPL1_NC_MODE_CNTL, lower_bit << 1);
>> -    gpu_write(gpu, REG_A6XX_SP_NC_MODE_CNTL,
>> -        uavflagprd_inv << 4 | lower_bit << 1);
>> -    gpu_write(gpu, REG_A6XX_UCHE_MODE_CNTL, lower_bit << 21);
>> +          rgb565_predicator << 11 | upper_bit << 10 | amsbc << 4 |
>> +          min_acc_len << 3 | lower_bit << 1 | ubwc_mode);
>> +
>> +    gpu_write(gpu, REG_A6XX_TPL1_NC_MODE_CNTL, upper_bit << 4 |
>> +          min_acc_len << 3 | lower_bit << 1 | ubwc_mode);
>> +
>> +    gpu_write(gpu, REG_A6XX_SP_NC_MODE_CNTL, upper_bit << 10 |
>> +          uavflagprd_inv << 4 | min_acc_len << 3 |
>> +          lower_bit << 1 | ubwc_mode);
>> +
>> +    gpu_write(gpu, REG_A6XX_UCHE_MODE_CNTL, min_acc_len << 23 | lower_bit << 21);
>>   }
>>     static int a6xx_cp_init(struct msm_gpu *gpu)
>