[PATCH v2] drm/amdgpu: add print for iommu translation mode

[Felix Kuehling]

On 2023-03-20 10:08, Graham Sider wrote:
> Add log to display whether RAM is direct vs DMA mapped.
>
> Signed-off-by: Graham Sider <Graham.Sider at amd.com>

Acked-by: Felix Kuehling <Felix.Kuehling at amd.com>


> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 6 +++++-
>   1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index 3bd6c5aef796..83774824694b 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -3528,8 +3528,12 @@ static void amdgpu_device_check_iommu_direct_map(struct amdgpu_device *adev)
>   	struct iommu_domain *domain;
>   
>   	domain = iommu_get_domain_for_dev(adev->dev);
> -	if (!domain || domain->type == IOMMU_DOMAIN_IDENTITY)
> +	if (!domain || domain->type == IOMMU_DOMAIN_IDENTITY) {
> +		dev_info(adev->dev, "RAM is direct mapped to GPU (not translated by IOMMU)\n");
>   		adev->ram_is_direct_mapped = true;
> +	} else {
> +		dev_info(adev->dev, "RAM is DMA mapped to GPU (translated by IOMMU)\n");
> +	}
>   }
>   
>   static const struct attribute *amdgpu_dev_attributes[] = {