gpu: nvgpu: cyclestats mode E snapshots support

That is a kernel supporting code for cyclestats mode E.
Cyclestats mode E implemented following Windows-design in user-space
and required the following operations to be implemented:
- attach a client for shared hardware buffer of device
- detach client from shared hardware buffer
- flush means copy of available data from hardware buffer to private
  client buffers according to perfmon IDs assigned for clients
- perfmon IDs management for user-space clients
- a NVGPU_GPU_FLAGS_SUPPORT_CYCLE_STATS_SNAPSHOT capability added

Bug 1573150

Change-Id: I9e09f0fbb2be5a95c47e6d80a2e23fa839b46f9a
Signed-off-by: Leonid Moiseichuk <lmoiseichuk@nvidia.com>
Reviewed-on: http://git-master/r/740653
(cherry picked from commit 79fe89fd4cea39d8ab9dbef0558cd806ddfda87f)
Reviewed-on: http://git-master/r/753274
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Tested-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/channel_gk20a.h b/drivers/gpu/nvgpu/gk20a/channel_gk20a.h
index 5fe03cef..f022fe36 100644
--- a/drivers/gpu/nvgpu/gk20a/channel_gk20a.h
+++ b/drivers/gpu/nvgpu/gk20a/channel_gk20a.h
@@ -133,6 +133,9 @@ struct channel_gk20a {
         struct dma_buf *cyclestate_buffer_handler;
         struct mutex cyclestate_buffer_mutex;
         } cyclestate;
+
+        struct mutex cs_client_mutex;
+        struct gk20a_cs_snapshot_client *cs_client;
 #endif
         struct mutex dbg_s_lock;
         struct list_head dbg_s_list;