Re: [PATCH 2/2] drm/msm: Fix duplicate gpu node in icc summary

[Akhil P Oommen <akhilpo@codeaurora.org>]

On 10/19/2020 8:29 PM, Jordan Crouse wrote:
> On Mon, Oct 19, 2020 at 06:49:18PM +0530, Akhil P Oommen wrote:
>> On targets with a6xx gpu, there is a duplicate gpu icc node listed in
>> the interconnect summary. On these targets, calling
> 
> This first sentence is confusing to me. I think the following few sentences do
> a better job of explaining what you are trying to do.
I can just remove that line.
> 
>> dev_pm_opp_of_add_table() api initializes the icc nodes for gpu indirectly.
>> So we should avoid using of_icc_get() api in the common probe path. To fix
>> this, we can move of_icc_get() to target specific code where it is
>> required.
> 
>> Signed-off-by: Akhil P Oommen <akhilpo@codeaurora.org>
>> ---
>>   drivers/gpu/drm/msm/adreno/a3xx_gpu.c   | 21 +++++++++++++++++++--
>>   drivers/gpu/drm/msm/adreno/a4xx_gpu.c   | 20 ++++++++++++++++++--
>>   drivers/gpu/drm/msm/adreno/adreno_gpu.c | 29 +----------------------------
>>   3 files changed, 38 insertions(+), 32 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/msm/adreno/a3xx_gpu.c b/drivers/gpu/drm/msm/adreno/a3xx_gpu.c
>> index f29c77d..93da668 100644
>> --- a/drivers/gpu/drm/msm/adreno/a3xx_gpu.c
>> +++ b/drivers/gpu/drm/msm/adreno/a3xx_gpu.c
>> @@ -519,6 +519,8 @@ struct msm_gpu *a3xx_gpu_init(struct drm_device *dev)
>>   	struct msm_gpu *gpu;
>>   	struct msm_drm_private *priv = dev->dev_private;
>>   	struct platform_device *pdev = priv->gpu_pdev;
>> +	struct icc_path *ocmem_icc_path;
>> +	struct icc_path *icc_path;
>>   	int ret;
>>   
>>   	if (!pdev) {
>> @@ -566,13 +568,28 @@ struct msm_gpu *a3xx_gpu_init(struct drm_device *dev)
>>   		goto fail;
>>   	}
>>   
>> +	icc_path = devm_of_icc_get(&pdev->dev, "gfx-mem");
>> +	ret = IS_ERR(icc_path);
>> +	if (ret)
>> +		goto fail;
>> +
>> +	ocmem_icc_path = devm_of_icc_get(&pdev->dev, "ocmem");
>> +	ret = IS_ERR(ocmem_icc_path);
>> +	if (ret) {
>> +		/* allow -ENODATA, ocmem icc is optional */
>> +		if (ret != -ENODATA)
>> +			goto fail;
>> +		ocmem_icc_path = NULL;
>> +	}
>> +
>> +
>>   	/*
>>   	 * Set the ICC path to maximum speed for now by multiplying the fastest
>>   	 * frequency by the bus width (8). We'll want to scale this later on to
>>   	 * improve battery life.
>>   	 */
>> -	icc_set_bw(gpu->icc_path, 0, Bps_to_icc(gpu->fast_rate) * 8);
>> -	icc_set_bw(gpu->ocmem_icc_path, 0, Bps_to_icc(gpu->fast_rate) * 8);
>> +	icc_set_bw(icc_path, 0, Bps_to_icc(gpu->fast_rate) * 8);
>> +	icc_set_bw(ocmem_icc_path, 0, Bps_to_icc(gpu->fast_rate) * 8);
> 
> This seems reasonable but I hope we can get somebody to sign off on a real a3xx
> part.
> 
>>   
>>   	return gpu;
>>   
>> diff --git a/drivers/gpu/drm/msm/adreno/a4xx_gpu.c b/drivers/gpu/drm/msm/adreno/a4xx_gpu.c
>> index 2b93b33..c0be3a0 100644
>> --- a/drivers/gpu/drm/msm/adreno/a4xx_gpu.c
>> +++ b/drivers/gpu/drm/msm/adreno/a4xx_gpu.c
>> @@ -648,6 +648,8 @@ struct msm_gpu *a4xx_gpu_init(struct drm_device *dev)
>>   	struct msm_gpu *gpu;
>>   	struct msm_drm_private *priv = dev->dev_private;
>>   	struct platform_device *pdev = priv->gpu_pdev;
>> +	struct icc_path *ocmem_icc_path;
>> +	struct icc_path *icc_path;
>>   	int ret;
>>   
>>   	if (!pdev) {
>> @@ -694,13 +696,27 @@ struct msm_gpu *a4xx_gpu_init(struct drm_device *dev)
>>   		goto fail;
>>   	}
>>   
>> +	icc_path = devm_of_icc_get(&pdev->dev, "gfx-mem");
>> +	ret = IS_ERR(icc_path);
>> +	if (ret)
>> +		goto fail;
>> +
>> +	ocmem_icc_path = devm_of_icc_get(&pdev->dev, "ocmem");
>> +	ret = IS_ERR(ocmem_icc_path);
>> +	if (ret) {
>> +		/* allow -ENODATA, ocmem icc is optional */
>> +		if (ret != -ENODATA)
>> +			goto fail;
>> +		ocmem_icc_path = NULL;
>> +	}
>> +
>>   	/*
>>   	 * Set the ICC path to maximum speed for now by multiplying the fastest
>>   	 * frequency by the bus width (8). We'll want to scale this later on to
>>   	 * improve battery life.
>>   	 */
>> -	icc_set_bw(gpu->icc_path, 0, Bps_to_icc(gpu->fast_rate) * 8);
>> -	icc_set_bw(gpu->ocmem_icc_path, 0, Bps_to_icc(gpu->fast_rate) * 8);
>> +	icc_set_bw(icc_path, 0, Bps_to_icc(gpu->fast_rate) * 8);
>> +	icc_set_bw(ocmem_icc_path, 0, Bps_to_icc(gpu->fast_rate) * 8);
> 
> Less confident we can find any 4xx fans to test this, but if a3xx works then so
> should this (in theory).
> 
>>   	return gpu;
>>   
>> diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
>> index fd8f491..6e3b820 100644
>> --- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
>> +++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
>> @@ -920,35 +920,8 @@ int adreno_gpu_init(struct drm_device *drm, struct platform_device *pdev,
>>   
>>   	ret = msm_gpu_init(drm, pdev, &adreno_gpu->base, &funcs->base,
>>   			adreno_gpu->info->name, &adreno_gpu_config);
>> -	if (ret)
>> -		return ret;
>> -
>> -	/*
>> -	 * The legacy case, before "interconnect-names", only has a
>> -	 * single interconnect path which is equivalent to "gfx-mem"
>> -	 */
>> -	if (!of_find_property(dev->of_node, "interconnect-names", NULL)) {
>> -		gpu->icc_path = of_icc_get(dev, NULL);
>> -	} else {
>> -		gpu->icc_path = of_icc_get(dev, "gfx-mem");
>> -		gpu->ocmem_icc_path = of_icc_get(dev, "ocmem");
>> -	}
>>   
>> -	if (IS_ERR(gpu->icc_path)) {
>> -		ret = PTR_ERR(gpu->icc_path);
>> -		gpu->icc_path = NULL;
>> -		return ret;
>> -	}
>> -
>> -	if (IS_ERR(gpu->ocmem_icc_path)) {
>> -		ret = PTR_ERR(gpu->ocmem_icc_path);
>> -		gpu->ocmem_icc_path = NULL;
>> -		/* allow -ENODATA, ocmem icc is optional */
>> -		if (ret != -ENODATA)
>> -			return ret;
>> -	}
>> -
>> -	return 0;
>> +	return ret;
> 
> This could go even further:
> 
> return msm_gpu_init(...);
> 
Yep, we can do that. Thanks for the feedback.

--Akhil
>>   }
>>   
>>   void adreno_gpu_cleanup(struct adreno_gpu *adreno_gpu)
>> -- 
>> 2.7.4
>>
>