drm/amdgpu: check before checking pci bridge registers

Make sure we are not the root device before attempting to
read the pcie bridge registers to check the pcie gen speeed.

Fixes a crash when the device is passed through to a VM.

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

diff --git a/drivers/gpu/drm/amd/amdgpu/cik.c b/drivers/gpu/drm/amd/amdgpu/cik.c
index 4b6ce74753cded5179b17eaf698ddd16766760b1..484710cfdf8243d563afe908c2b9c9884879f971 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/cik.c
+++ b/drivers/gpu/drm/amd/amdgpu/cik.c
@@ -1567,6 +1567,9 @@ static void cik_pcie_gen3_enable(struct amdgpu_device *adev)
        int ret, i;
        u16 tmp16;
 
+       if (pci_is_root_bus(adev->pdev->bus))
+               return;
+
        if (amdgpu_pcie_gen2 == 0)
                return;
 

diff --git a/drivers/gpu/drm/amd/amdgpu/vi.c b/drivers/gpu/drm/amd/amdgpu/vi.c
index b55ceb14fdcd91e92f7a5924a232490a6419a80a..0bac8702e9348c2ee9c86ed52d6aaf490ef5032f 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/vi.c
+++ b/drivers/gpu/drm/amd/amdgpu/vi.c
@@ -1005,6 +1005,9 @@ static void vi_pcie_gen3_enable(struct amdgpu_device *adev)
        u32 mask;
        int ret;
 
+       if (pci_is_root_bus(adev->pdev->bus))
+               return;
+
        if (amdgpu_pcie_gen2 == 0)
                return;