gpu: nvgpu: Unify remove/shutdown codepaths

The following changes are part of the porting of the bind/unbind
functionality.

These changes reuse the shutdown codepaths in iGPU and dGPU and fix a locking
issue with in gk20a_busy() where the usage count can lead to a deadlock during
the driver shutdown. It fixes a racing condition with the gr/mm code by
invalidating the sw ready flag while holding the busy lock

JIRA: EVLR-1739

Change-Id: I62ce47378436b21f447f4cd93388759ed3f9bad1
Signed-off-by: David Nieto <dmartineznie@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1554959
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: svccoveritychecker <svccoveritychecker@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 1 insertions, 2 deletions

diff --git a/drivers/gpu/nvgpu/clk/clk_arb.c b/drivers/gpu/nvgpu/clk/clk_arb.c
index 0204627b..4f09da74 100644
--- a/drivers/gpu/nvgpu/clk/clk_arb.c
+++ b/drivers/gpu/nvgpu/clk/clk_arb.c
@@ -489,9 +489,8 @@ void nvgpu_clk_arb_cleanup_arbiter(struct gk20a *g)
                         nvgpu_kfree(g, arb->vf_table_pool[index].gpc2clk_points);
                         nvgpu_kfree(g, arb->vf_table_pool[index].mclk_points);
                 }
+                nvgpu_mutex_destroy(&g->clk_arb->pstate_lock);
         }
-
-        nvgpu_mutex_destroy(&g->clk_arb->pstate_lock);
         nvgpu_kfree(g, g->clk_arb);
         g->clk_arb = NULL;
 }