[PATCH 1/1] drm/amdgpu: Use GTT for dumb buffer if sg display enabled

[Michel Dänzer]

On 2018-05-22 01:22 AM, Deepak Sharma wrote:
> When vram size <= THRESHOLD(256M) lets use GTT for dumb buffer
> allocation. As SG will be enabled with vram size <= 256M
> scan out will not be an issue.
> 
> Signed-off-by: Deepak Sharma <Deepak.Sharma at amd.com>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> index 2c8e27370284..c547d92dbf4e 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> @@ -749,15 +749,18 @@ int amdgpu_mode_dumb_create(struct drm_file *file_priv,
>  	struct amdgpu_device *adev = dev->dev_private;
>  	struct drm_gem_object *gobj;
>  	uint32_t handle;
> +	u32 domain;
>  	int r;
>  
>  	args->pitch = amdgpu_align_pitch(adev, args->width,
>  					 DIV_ROUND_UP(args->bpp, 8), 0);
>  	args->size = (u64)args->pitch * args->height;
>  	args->size = ALIGN(args->size, PAGE_SIZE);
> +	domain = AMDGPU_GEM_DOMAIN_VRAM;
> +	if (adev->gmc.real_vram_size <= AMDGPU_SG_THRESHOLD)
> +		domain = AMDGPU_GEM_DOMAIN_GTT;

This could choose GTT even in cases where scanout from that isn't
supported.

It should call amdgpu_display_supported_domains, and then use the same
logic as in amdgpu_bo_pin_restricted:

        if (domain == (AMDGPU_GEM_DOMAIN_VRAM | AMDGPU_GEM_DOMAIN_GTT)) {
                domain = AMDGPU_GEM_DOMAIN_VRAM;
                if (adev->gmc.real_vram_size <= AMDGPU_SG_THRESHOLD)
                        domain = AMDGPU_GEM_DOMAIN_GTT;
        }

Maybe this logic could be refactored into a helper function.


-- 
Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer