nvgpu: gpu: include qnx_init unit in doxygen documentation

-Include qnx_init unit in doxygen documentation.
-Add documentation for gk20a_busy/idle and similar functions.
-Remove must_check return value as misra already reports violation for
 that.

Jira NVGPU-2571

Change-Id: I9573cb61865677944809dcc494d92f63cc6e0f58
Signed-off-by: Shashank Singh <shashsingh@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/2176755
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
Reviewed-by: svc-mobile-misra <svc-mobile-misra@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Alex Waterman <alexw@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

drivers/gpu/nvgpu/common/debugger.c

@@ -33,6 +33,7 @@
 #include <nvgpu/channel.h>
 #include <nvgpu/unit.h>
 #include <nvgpu/gk20a.h>
+#include <nvgpu/nvgpu_init.h>
 #include <nvgpu/debugger.h>
 #include <nvgpu/power_features/power_features.h>
 

drivers/gpu/nvgpu/common/fifo/channel.c

@@ -46,6 +46,7 @@
 #include <nvgpu/ptimer.h>
 #include <nvgpu/worker.h>
 #include <nvgpu/gk20a.h>
+#include <nvgpu/nvgpu_init.h>
 #include <nvgpu/engines.h>
 #include <nvgpu/channel.h>
 #include <nvgpu/channel_sync.h>

drivers/gpu/nvgpu/common/fifo/submit.c

@@ -21,6 +21,7 @@
  */
 
 #include <nvgpu/gk20a.h>
+#include <nvgpu/nvgpu_init.h>
 #include <nvgpu/channel.h>
 #include <nvgpu/ltc.h>
 #include <nvgpu/os_sched.h>

drivers/gpu/nvgpu/common/gr/fecs_trace.c

@@ -21,6 +21,7 @@
  */
 
 #include <nvgpu/gk20a.h>
+#include <nvgpu/nvgpu_init.h>
 #include <nvgpu/list.h>
 #include <nvgpu/log.h>
 #include <nvgpu/log2.h>

drivers/gpu/nvgpu/common/perf/perfbuf.c

@@ -24,6 +24,7 @@
 #include <nvgpu/sizes.h>
 #include <nvgpu/perfbuf.h>
 #include <nvgpu/gk20a.h>
+#include <nvgpu/nvgpu_init.h>
 
 int nvgpu_perfbuf_enable_locked(struct gk20a *g, u64 offset, u32 size)
 {

drivers/gpu/nvgpu/common/pmu/perfmon/pmu_perfmon.c

@@ -22,6 +22,7 @@
 
 #include <nvgpu/pmu/pmu_perfmon.h>
 #include <nvgpu/gk20a.h>
+#include <nvgpu/nvgpu_init.h>
 #include <nvgpu/falcon.h>
 #include <nvgpu/bug.h>
 #include <nvgpu/enabled.h>

drivers/gpu/nvgpu/common/ptimer/ptimer.c

@@ -24,6 +24,7 @@
 #include <nvgpu/ptimer.h>
 #include <nvgpu/timers.h>
 #include <nvgpu/gk20a.h>
+#include <nvgpu/nvgpu_init.h>
 
 int nvgpu_get_timestamps_zipper(struct gk20a *g,
 		u32 source_id, u32 count,

drivers/gpu/nvgpu/hal/clk/clk_gm20b.c

@@ -31,6 +31,7 @@
 #include <nvgpu/utils.h>
 #include <nvgpu/timers.h>
 #include <nvgpu/gk20a.h>
+#include <nvgpu/nvgpu_init.h>
 #include <nvgpu/therm.h>
 #include <nvgpu/pmu/pmuif/ctrlclk.h>
 

drivers/gpu/nvgpu/hal/mm/cache/flush_gk20a.c

@@ -27,6 +27,7 @@
 #include <nvgpu/mm.h>
 #include <nvgpu/io.h>
 #include <nvgpu/gk20a.h>
+#include <nvgpu/nvgpu_init.h>
 #include <nvgpu/timers.h>
 
 #include <nvgpu/hw/gk20a/hw_flush_gk20a.h>

drivers/gpu/nvgpu/hal/mm/cache/flush_gk20a_fusa.c

@@ -27,6 +27,7 @@
 #include <nvgpu/mm.h>
 #include <nvgpu/io.h>
 #include <nvgpu/gk20a.h>
+#include <nvgpu/nvgpu_init.h>
 #include <nvgpu/timers.h>
 
 #include <nvgpu/hw/gk20a/hw_flush_gk20a.h>

drivers/gpu/nvgpu/include/nvgpu/gk20a.h

@@ -39,6 +39,7 @@
  *   - @ref unit-devctl
  *   - @ref unit-sdl
  *   - @ref unit-init
+ *   - @ref unit-qnx_init
  *   - @ref unit-falcon
  *   - @ref unit-os_utils
  *   - @ref unit-acr
@@ -2329,10 +2330,6 @@ bool is_nvgpu_gpu_state_valid(struct gk20a *g);
 #define GK20A_BAR1_IORESOURCE_MEM	1U
 #define GK20A_SIM_IORESOURCE_MEM	2U
 
-void gk20a_busy_noresume(struct gk20a *g);
-void gk20a_idle_nosuspend(struct gk20a *g);
-int __must_check gk20a_busy(struct gk20a *g);
-void gk20a_idle(struct gk20a *g);
 #ifdef CONFIG_PM
 int gk20a_do_idle_impl(struct gk20a *g, bool force_reset);
 int gk20a_do_unidle_impl(struct gk20a *g);

drivers/gpu/nvgpu/include/nvgpu/nvgpu_init.h

@@ -163,7 +163,7 @@ int nvgpu_can_busy(struct gk20a *g);
  *
  * @return pointer to g if successful, otherwise 0.
  */
-struct gk20a * __must_check nvgpu_get(struct gk20a *g);
+struct gk20a * nvgpu_get(struct gk20a *g);
 
 /**
  * @brief Decrement ref count on driver.
@@ -192,4 +192,41 @@ void nvgpu_check_gpu_state(struct gk20a *g);
  */
 void nvgpu_init_gpu_characteristics(struct gk20a *g);
 
+/**
+ * @brief Takes a reference for keeping gpu busy but not try to initialize it.
+ * Does nothing for safety.
+ *
+ * @param g [in] The GPU
+ */
+void gk20a_busy_noresume(struct gk20a *g);
+
+/**
+ * @brief Drops a reference for gpu. Does nothing for safety.
+ *
+ * @param g [in] The GPU
+ */
+void gk20a_idle_nosuspend(struct gk20a *g);
+
+/**
+ * @brief Takes a reference for keeping gpu busy and initialize it if this is
+ * first reference. Also, takes a power ref if power saving is supported. On
+ * safety it just checks if GPU is in usable state.
+ *
+ * @param g [in] The GPU
+ *
+ * @return 0 in case of success, -ENODEV in case of failure.
+ *
+ * This is called mostly by the devctl path to check if proceeding further is
+ * allowed or not.
+ */
+int gk20a_busy(struct gk20a *g);
+
+/**
+ * @brief Drops a reference for gpu, put on idle if power saving is supported
+ * and power ref goes to 0. Does nothing for safety.
+ *
+ * @param g [in] The GPU
+ */
+void gk20a_idle(struct gk20a *g);
+
 #endif /* NVGPU_INIT_H */

drivers/gpu/nvgpu/os/linux/cde.c

@@ -40,6 +40,7 @@
 #include <nvgpu/runlist.h>
 #include <nvgpu/utils.h>
 #include <nvgpu/gk20a.h>
+#include <nvgpu/nvgpu_init.h>
 #include <nvgpu/string.h>
 #include <nvgpu/fence.h>
 

drivers/gpu/nvgpu/os/linux/debug_bios.c

@@ -13,6 +13,7 @@
  */
 
 #include <nvgpu/types.h>
+#include <nvgpu/nvgpu_init.h>
 
 #include "debug_bios.h"
 #include "os_linux.h"

drivers/gpu/nvgpu/os/linux/debug_fecs_trace.c

@@ -17,6 +17,7 @@
 #include <linux/debugfs.h>
 
 #include <nvgpu/gr/fecs_trace.h>
+#include <nvgpu/nvgpu_init.h>
 
 #include "os_linux.h"
 

drivers/gpu/nvgpu/os/linux/debug_ltc.c

@@ -16,6 +16,7 @@
 #include "os_linux.h"
 
 #include <nvgpu/gk20a.h>
+#include <nvgpu/nvgpu_init.h>
 
 #include <linux/debugfs.h>
 #include <linux/uaccess.h>

drivers/gpu/nvgpu/os/linux/debug_pmu.c

@@ -17,6 +17,7 @@
 #include <nvgpu/pmu/debug.h>
 #include <nvgpu/pmu/pmu_pg.h>
 #include <nvgpu/pmu/fw.h>
+#include <nvgpu/nvgpu_init.h>
 
 #include "debug_pmu.h"
 #include "os_linux.h"

drivers/gpu/nvgpu/os/linux/debug_sched.c

@@ -14,6 +14,7 @@
 
 #include "debug_sched.h"
 #include "os_linux.h"
+#include <nvgpu/nvgpu_init.h>
 
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>

drivers/gpu/nvgpu/os/linux/ioctl_as.c

@@ -27,6 +27,7 @@
 #include <nvgpu/vm_area.h>
 #include <nvgpu/log2.h>
 #include <nvgpu/gk20a.h>
+#include <nvgpu/nvgpu_init.h>
 #include <nvgpu/channel.h>
 
 #include <nvgpu/linux/vm.h>

drivers/gpu/nvgpu/os/linux/sysfs.c

@@ -33,6 +33,7 @@
 #include <nvgpu/pmu/pmu_perfmon.h>
 #include <nvgpu/pmu/fw.h>
 #include <nvgpu/pmu/pmu_pg.h>
+#include <nvgpu/nvgpu_init.h>
 
 #include "os_linux.h"
 #include "sysfs.h"