drm/amdgpu: add coreboot workaround for KV/KB

Coreboot seems to have a problem correctly setting up access to the stolen VRAM
on KV/KB. Use the direct access only when necessary.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reported-and-tested-by: Fredrik Bruhn <fredrik.bruhn@unibap.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Christian König 2020-01-16 14:06:59 +01:00 committed by Alex Deucher
parent da2f84ba73
commit 77171eade8

View File

@ -381,7 +381,8 @@ static int gmc_v7_0_mc_init(struct amdgpu_device *adev)
adev->gmc.aper_size = pci_resource_len(adev->pdev, 0);
#ifdef CONFIG_X86_64
if (adev->flags & AMD_IS_APU) {
if (adev->flags & AMD_IS_APU &&
adev->gmc.real_vram_size > adev->gmc.aper_size) {
adev->gmc.aper_base = ((u64)RREG32(mmMC_VM_FB_OFFSET)) << 22;
adev->gmc.aper_size = adev->gmc.real_vram_size;
}