gpu: nvgpu: Add debugfs wrapper for exposing profilers

The current debugfs code is completely specific to FIFO's kickoff
profiler. But exposing these debugfs nodes is really a perfectly
generic operation to any given profiler.

Therefore add a generic debugfs interface for exposing profilers.
Any code that implements a profiler can now use a single function
call to export a profiler to the GPU debugfs area.

JIRA NVGPU-5606

Change-Id: I67a5bd9998fcfac94678e465442b9a38ab7e7612
Signed-off-by: Alex Waterman <alexw@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvgpu/+/2358382
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>

drivers/gpu/nvgpu/os/linux/swprofile_debugfs.h

@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2020 NVIDIA Corporation.  All rights reserved.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __NVGPU_PROFILE_DEBUGFS_H__
+#define __NVGPU_PROFILE_DEBUGFS_H__
+
+struct dentry;
+
+struct gk20a;
+struct nvgpu_swprofiler;
+
+void nvgpu_debugfs_swprofile_init(struct gk20a *g,
+				  struct dentry *root,
+				  struct nvgpu_swprofiler *p,
+				  const char *name);
+
+#endif /* __NVGPU_PROFILE_DEBUGFS_H__ */