drm/amdgpu: skip BAR resizing if the bios already did it

No need to do it again.
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_device.c

@@ -909,6 +909,11 @@ int amdgpu_device_resize_fb_bar(struct amdgpu_device *adev)
 	if (amdgpu_sriov_vf(adev))
 		return 0;
 
+	/* skip if the bios has already enabled large BAR */
+	if (adev->gmc.real_vram_size &&
+	    (pci_resource_len(adev->pdev, 0) >= adev->gmc.real_vram_size))
+		return 0;
+
 	/* Check if the root BUS has 64bit memory resources */
 	root = adev->pdev->bus;
 	while (root->parent)