[PATCH 3/4] drm/amdgpu: Only overwrite serial if field is empty

[Kent Russell]

On Aldebaran, the serial may be obtained from the FRU. Only overwrite
the serial with the unique_id if the serial is empty. This will support
printing serial numbers for mGPU devices where there are 2 unique_ids
for the 2 GPUs, but only one serial number for the board

Signed-off-by: Kent Russell <kent.russell at amd.com>
---
 drivers/gpu/drm/amd/pm/swsmu/smu13/aldebaran_ppt.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu13/aldebaran_ppt.c b/drivers/gpu/drm/amd/pm/swsmu/smu13/aldebaran_ppt.c
index 6e781cee8bb6..dfcf9a53e5ea 100644
--- a/drivers/gpu/drm/amd/pm/swsmu/smu13/aldebaran_ppt.c
+++ b/drivers/gpu/drm/amd/pm/swsmu/smu13/aldebaran_ppt.c
@@ -1615,7 +1615,8 @@ static void aldebaran_get_unique_id(struct smu_context *smu)
 	mutex_unlock(&smu->metrics_lock);
 
 	adev->unique_id = ((uint64_t)upper32 << 32) | lower32;
-	sprintf(adev->serial, "%016llx", adev->unique_id);
+	if (adev->serial[0] == '\0')
+		sprintf(adev->serial, "%016llx", adev->unique_id);
 }
 
 static bool aldebaran_is_baco_supported(struct smu_context *smu)
-- 
2.25.1