drm/amdgpu: Skip the VRAM base offset on SRIOV

[Why]
As VF cannot read MMMC_VM_FB_OFFSET with L1 Policy(read 0xffffffff).
It leads to driver get the incorrect vram base offset.

[How]
Since SR-IOV is dGPU only, skip reading this register and set the
fb_offest to 0.

Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Yifan Zha <Yifan.Zha@amd.com>
Signed-off-by: Horace Chen <horace.chen@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c
index 592729c..846ccb6 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c
@@ -649,7 +649,10 @@ static void gmc_v11_0_vram_gtt_location(struct amdgpu_device *adev,
        amdgpu_gmc_gart_location(adev, mc);
 
        /* base offset of vram pages */
-       adev->vm_manager.vram_base_offset = adev->mmhub.funcs->get_mc_fb_offset(adev);
+       if (amdgpu_sriov_vf(adev))
+               adev->vm_manager.vram_base_offset = 0;
+       else
+               adev->vm_manager.vram_base_offset = adev->mmhub.funcs->get_mc_fb_offset(adev);
 }
 
 /**