[PATCH V2 2/2] drm/amdkfd: use GTT for VRAM on APUs only if GTT is larger

[Mario Limonciello]

On 1/31/2025 11:21, Alex Deucher wrote:
> If the user has configured a large carveout on a small APU,
> only use GTT for VRAM allocations if GTT is larger than
> VRAM.
> 
> v2: fix reversed check (Philip)
> 
> Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 6 ++++--
>   1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> index 32b42f1104623..1b8d7c4889341 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> @@ -1989,8 +1989,10 @@ int amdgpu_ttm_init(struct amdgpu_device *adev)
>   	DRM_INFO("amdgpu: %uM of GTT memory ready.\n",
>   		 (unsigned int)(gtt_size / (1024 * 1024)));
>   
> -	if (adev->flags & AMD_IS_APU)
> -		adev->apu_prefer_gtt = true;
> +	if (adev->flags & AMD_IS_APU) {
> +		if (adev->gmc.real_vram_size < gtt_size)
> +			adev->apu_prefer_gtt = true;
> +	}
>   
>   	/* Initialize doorbell pool on PCI BAR */
>   	r = amdgpu_ttm_init_on_chip(adev, AMDGPU_PL_DOORBELL, adev->doorbell.size / PAGE_SIZE);

For both patches:

Reviewed-by: Mario Limonciello <mario.limonciello at amd.com>