gpu: nvgpu: Add reboot handler

Add a reboot handler to make sure that nvgpu does not try to busy
the GPU if the system is going down. If the system is going down
then any number of subsystems nvgpu depends on may already have
been deinitialized.

Bug 200333709
Bug 200454316

Change-Id: I2ceaf7ca4fb88643310874b5b26937ef44c6e3dd
Signed-off-by: Kary Jin <karyj@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1927018
Reviewed-by: Automatic_Commit_Validation_User
GVS: Gerrit_Virtual_Submit
Reviewed-by: Vinayak Pane <vpane@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

2 files changed, 8 insertions, 1 deletions

diff --git a/drivers/gpu/nvgpu/include/nvgpu/enabled.h b/drivers/gpu/nvgpu/include/nvgpu/enabled.h
index 074be0c3..12acf353 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/enabled.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/enabled.h
@@ -36,6 +36,7 @@ struct gk20a;
 #define NVGPU_GR_USE_DMA_FOR_FW_BOOTSTRAP 3
 #define NVGPU_FECS_TRACE_VA                     4
 #define NVGPU_CAN_RAILGATE                      5
+#define NVGPU_KERNEL_IS_DYING                   6
 
 /*
  * ECC flags
diff --git a/drivers/gpu/nvgpu/include/nvgpu/gk20a.h b/drivers/gpu/nvgpu/include/nvgpu/gk20a.h
index a256b01f..0424e74d 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/gk20a.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/gk20a.h
@@ -49,6 +49,9 @@ struct nvgpu_gpu_ctxsw_trace_filter;
 struct priv_cmd_entry;
 struct nvgpu_gpfifo_args;
 
+#ifdef __KERNEL__
+#include <linux/notifier.h>
+#endif
 #include <nvgpu/lock.h>
 #include <nvgpu/thread.h>
 
@@ -1411,6 +1414,10 @@ struct gk20a {
          */
         unsigned long *enabled_flags;
 
+#ifdef __KERNEL__
+        struct notifier_block nvgpu_reboot_nb;
+#endif
+
         nvgpu_atomic_t usage_count;
 
         struct nvgpu_mutex ctxsw_disable_lock;
@@ -1741,7 +1748,6 @@ void gk20a_idle(struct gk20a *g);
 int __gk20a_do_idle(struct gk20a *g, bool force_reset);
 int __gk20a_do_unidle(struct gk20a *g);
 
-int gk20a_can_busy(struct gk20a *g);
 int gk20a_wait_for_idle(struct gk20a *g);
 
 #define NVGPU_GPU_ARCHITECTURE_SHIFT 4