[PATCH V2 1/2] drm/amdgpu: Move xgmi ras initialization from .late_init to .early_init

[Chai, Thomas]

-----Original Message-----
From: Lazar, Lijo <Lijo.Lazar at amd.com> 
Sent: Thursday, January 20, 2022 1:49 PM
To: Chai, Thomas <YiPeng.Chai at amd.com>; amd-gfx at lists.freedesktop.org
Cc: Zhou1, Tao <Tao.Zhou1 at amd.com>; Zhang, Hawking <Hawking.Zhang at amd.com>; Clements, John <John.Clements at amd.com>; Chai, Thomas <YiPeng.Chai at amd.com>
Subject: Re: [PATCH V2 1/2] drm/amdgpu: Move xgmi ras initialization from .late_init to .early_init



On 1/20/2022 8:48 AM, yipechai wrote:
> Move xgmi ras initialization from .late_init to .early_init, which let 
> xgmi ras can be initialized only once.
> 
> Signed-off-by: yipechai <YiPeng.Chai at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c | 15 ++++++++++-----
>   drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.h |  1 +
>   drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c  |  5 +++++
>   drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c   |  5 +++++
>   4 files changed, 21 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c 
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c
> index 3483a82f5734..788c0257832d 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c
> @@ -436,6 +436,16 @@ void amdgpu_gmc_filter_faults_remove(struct amdgpu_device *adev, uint64_t addr,
>   	} while (fault->timestamp < tmp);
>   }
>   
> +int amdgpu_gmc_ras_early_init(struct amdgpu_device *adev) {
> +	if (!adev->gmc.xgmi.connected_to_cpu) {
> +		adev->gmc.xgmi.ras = &xgmi_ras;
> +		amdgpu_ras_register_ras_block(adev, &adev->gmc.xgmi.ras->ras_block);
> +	}
> +
> +	return 0;
> +}
> +
>   int amdgpu_gmc_ras_late_init(struct amdgpu_device *adev)
>   {
>   	int r;
> @@ -452,11 +462,6 @@ int amdgpu_gmc_ras_late_init(struct amdgpu_device *adev)
>   			return r;
>   	}
>   
> -	if (!adev->gmc.xgmi.connected_to_cpu) {
> -		adev->gmc.xgmi.ras = &xgmi_ras;
> -		amdgpu_ras_register_ras_block(adev, &adev->gmc.xgmi.ras->ras_block);
> -	}
> -
>   	if (adev->gmc.xgmi.ras && adev->gmc.xgmi.ras->ras_block.ras_late_init) {
>   		r = adev->gmc.xgmi.ras->ras_block.ras_late_init(adev, NULL);
>   		if (r)
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.h 
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.h
> index 0001631cfedb..ac4c0e50b45c 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.h
> @@ -318,6 +318,7 @@ bool amdgpu_gmc_filter_faults(struct amdgpu_device *adev,
>   			      uint16_t pasid, uint64_t timestamp);
>   void amdgpu_gmc_filter_faults_remove(struct amdgpu_device *adev, uint64_t addr,
>   				     uint16_t pasid);
> +int amdgpu_gmc_ras_early_init(struct amdgpu_device *adev);
>   int amdgpu_gmc_ras_late_init(struct amdgpu_device *adev);
>   void amdgpu_gmc_ras_fini(struct amdgpu_device *adev);
>   int amdgpu_gmc_allocate_vm_inv_eng(struct amdgpu_device *adev); diff 
> --git a/drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c 
> b/drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c
> index 4f8d356f8432..7a6ad5d467b2 100644
> --- a/drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c
> +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c
> @@ -719,6 +719,7 @@ static void gmc_v10_0_set_gfxhub_funcs(struct 
> amdgpu_device *adev)
>   
>   static int gmc_v10_0_early_init(void *handle)
>   {
> +	int r;
>   	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
>   
>   	gmc_v10_0_set_mmhub_funcs(adev);
> @@ -734,6 +735,10 @@ static int gmc_v10_0_early_init(void *handle)
>   	adev->gmc.private_aperture_end =
>   		adev->gmc.private_aperture_start + (4ULL << 30) - 1;
>   
> +	r = amdgpu_gmc_ras_early_init(adev);
> +	if (r)
> +		return r;
> +

>At this point it's unknown if RAS is applicable for the SKU. I think this failure check shouldn't be there (here and below one).

>amdgpu_gmc_ras_early_init is return 0 always, that way also this check is not needed.

[Thomas]  Just like calling amdgpu_gmc_ras_late_init,  checking the return status may make the code extensible.  
	   In amdgpu_gmc_ras_early_init,  the xgmi ras initialization may always return 0, but it may add functions that need to check the return status in future.

Thanks,
Lijo

>   	return 0;
>   }
>   
> diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c 
> b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> index c76ffd1a70cd..3cdd3d459d51 100644
> --- a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> @@ -1318,6 +1318,7 @@ static void gmc_v9_0_set_mca_funcs(struct 
> amdgpu_device *adev)
>   
>   static int gmc_v9_0_early_init(void *handle)
>   {
> +	int r;
>   	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
>   
>   	/* ARCT and VEGA20 don't have XGMI defined in their IP discovery 
> tables */ @@ -1347,6 +1348,10 @@ static int gmc_v9_0_early_init(void *handle)
>   	adev->gmc.private_aperture_end =
>   		adev->gmc.private_aperture_start + (4ULL << 30) - 1;
>   
> +	r = amdgpu_gmc_ras_early_init(adev);
> +	if (r)
> +		return r;
> +
>   	return 0;
>   }
>   
>