drm/amdgpu: The VI specific EXE bit should only apply to GMC v8.0 above

BugLink: http://bugs.launchpad.net/bugs/1553179

commit 8f3c1629 upstream.
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Ken Wang <Qingqing.Wang@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

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

@@ -808,7 +808,7 @@ uint32_t amdgpu_ttm_tt_pte_flags(struct amdgpu_device *adev, struct ttm_tt *ttm,
 			flags |= AMDGPU_PTE_SNOOPED;
 	}
 
-	if (adev->asic_type >= CHIP_TOPAZ)
+	if (adev->asic_type >= CHIP_TONGA)
 		flags |= AMDGPU_PTE_EXECUTABLE;
 
 	flags |= AMDGPU_PTE_READABLE;