[PATCH] drm/amdkfd: fix clock counter retrieval for node without GPU

[Felix Kuehling]

From: Andres Rodriguez <andres.rodriguez at amd.com>

Currently if a user requests clock counters for a node without a GPU
resource we will always return EINVAL.

Instead if no GPU resource is attached, fill the gpu_clock_counter
argument with zeroes so that we may proceed and return valid CPU
counters.

Signed-off-by: Andres Rodriguez <andres.rodriguez at amd.com>
Signed-off-by: Felix Kuehling <Felix.Kuehling at amd.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_chardev.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
index cd679cf..b5e5f0e 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
@@ -749,12 +749,13 @@ static int kfd_ioctl_get_clock_counters(struct file *filep,
 	struct timespec64 time;
 
 	dev = kfd_device_by_id(args->gpu_id);
-	if (dev == NULL)
-		return -EINVAL;
-
-	/* Reading GPU clock counter from KGD */
-	args->gpu_clock_counter =
-		dev->kfd2kgd->get_gpu_clock_counter(dev->kgd);
+	if (dev)
+		/* Reading GPU clock counter from KGD */
+		args->gpu_clock_counter =
+			dev->kfd2kgd->get_gpu_clock_counter(dev->kgd);
+	else
+		/* Node without GPU resource */
+		args->gpu_clock_counter = 0;
 
 	/* No access to rdtsc. Using raw monotonic time */
 	getrawmonotonic64(&time);
-- 
2.7.4