Revert "gpu: nvgpu: return error from mutex_acquire() if pmu not initialized"

This reverts commit 50497d4031103df1067f14ce4c1e14b15713efb9.

Simply returning error from mutex_acquire() causes the code
to call disable_elpg() which decreases elpg refcount
But we already have a race condition between pmu initialization
where we initialize elpg and runlist update where we call
this mutex_acquire and decrease the refcount

As a result of this race and returned error we might mess up
with the elpg refcount and cause abnormal behaviour

Hence revert this change for now until we have clean fix
considering this race as well

Bug 200024116

Change-Id: Ie64ca36f70aba6b15c2acc235a5d36d13c9025aa
Signed-off-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-on: http://git-master/r/441793
Reviewed-by: Arto Merilainen <amerilainen@nvidia.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/pmu_gk20a.c b/drivers/gpu/nvgpu/gk20a/pmu_gk20a.c
index 3abf1b43..c23d83cf 100644
--- a/drivers/gpu/nvgpu/gk20a/pmu_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/pmu_gk20a.c
@@ -1227,7 +1227,7 @@ int pmu_mutex_acquire(struct pmu_gk20a *pmu, u32 id, u32 *token)
         u32 data, owner, max_retry;
 
         if (!pmu->initialized)
-                return -EINVAL;
+                return 0;
 
         BUG_ON(!token);
         BUG_ON(!PMU_MUTEX_ID_IS_VALID(id));
@@ -1296,7 +1296,7 @@ int pmu_mutex_release(struct pmu_gk20a *pmu, u32 id, u32 *token)
         u32 owner, data;
 
         if (!pmu->initialized)
-                return -EINVAL;
+                return 0;
 
         BUG_ON(!token);
         BUG_ON(!PMU_MUTEX_ID_IS_VALID(id));