amdgpu: Don't print L2 status if there's nothing to print

If a 2nd fault comes in before the 1st is handled, the 1st fault will
clear out the FAULT STATUS registers before the 2nd fault is handled.
Thus we get a lot of zeroes. If status=0, just skip the L2 fault status
information, to avoid confusion of why some VM fault status prints in
dmesg are all zeroes.

Signed-off-by: Kent Russell <kent.russell@amd.com>
Reviewed-by: Felix Kuehling <felix.kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
index 010db0e58650..f43ded8a0aab 100644
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
@@ -672,6 +672,12 @@ static int gmc_v9_0_process_interrupt(struct amdgpu_device *adev,
 	    (amdgpu_ip_version(adev, GC_HWIP, 0) >= IP_VERSION(9, 4, 2)))
 		return 0;
 
+	/* Only print L2 fault status if the status register could be read and
+	 * contains useful information
+	 */
+	if (!status)
+		return 0;
+
 	if (!amdgpu_sriov_vf(adev))
 		WREG32_P(hub->vm_l2_pro_fault_cntl, 1, ~1);