Message-ID: <b844c47e-8ee4-8163-3888-43a06edfd1a2@linaro.org>
Date:   Wed, 1 Feb 2023 11:51:04 +0100
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Subject: Re: [PATCH 02/14] drm/msm/a6xx: Extend UBWC config
Content-Language: en-US
To:     Akhil P Oommen <quic_akhilpo@quicinc.com>,
        linux-arm-msm@vger.kernel.org, andersson@kernel.org,
        agross@kernel.org, krzysztof.kozlowski@linaro.org
Cc:     marijn.suijten@somainline.org, Rob Clark <robdclark@gmail.com>,
        Abhinav Kumar <quic_abhinavk@quicinc.com>,
        Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        Sean Paul <sean@poorly.run>, David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>, Chia-I Wu <olvaffe@gmail.com>,
        Douglas Anderson <dianders@chromium.org>,
        dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org,
        linux-kernel@vger.kernel.org
References: <20230126151618.225127-1-konrad.dybcio@linaro.org>
 <20230126151618.225127-3-konrad.dybcio@linaro.org>
 <3644f111-0d69-1006-f032-782e1b00cd17@quicinc.com>
From:   Konrad Dybcio <konrad.dybcio@linaro.org>
In-Reply-To: <3644f111-0d69-1006-f032-782e1b00cd17@quicinc.com>
Content-Type: text/plain; charset=UTF-8
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Precedence: bulk


On 1.02.2023 10:30, Akhil P Oommen wrote:
> On 1/26/2023 8:46 PM, 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@linaro.org>
>> ---
>>  drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 26 ++++++++++++++++++--------
>>  1 file changed, 18 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..ad5d791b804c 100644
>> --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>> @@ -786,17 +786,22 @@ 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;
> Wouldn't this break a630?

// highest_bank_bit = 15 on 845, from "qcom,highest-bank-bit" in dt

bit = adreno_dev->highest_bank_bit ? adreno_dev->highest_bank_bit - 13 : 0;
// => bit = 2

lower_bit = bit & 0x3;
// => lower_bit = 2

Yes it would! Thanks for catching that, I'll add the A630 case in v2.

The 1 default value comes from the fact that highest_bank_bit is 13
when it's unset in dt, which makes lower_bit 1.


Konrad

> 
> -Akhil.
>> +	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_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 +812,23 @@ 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)
>