gpu: nvgpu: Add timeout API

Add a timeout API to nvgpu since this is a common operation done all
across the nvgpu driver.

Also add two new directories for this common code:

  drivers/gpu/nvgpu/common
  drivers/gpu/nvgpu/include/nvgpu

The common directory is for common C code. The include directory is for
common include files.

Bug 1799159

Change-Id: I8b710eecaa75c0707df83f859fb28484525185a6
Signed-off-by: Alex Waterman <alexw@nvidia.com>
Reviewed-on: http://git-master/r/1255864
GVS: Gerrit_Virtual_Submit
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 94 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/include/nvgpu/timers.h b/drivers/gpu/nvgpu/include/nvgpu/timers.h
new file mode 100644
index 00000000..e46982c9
--- /dev/null
+++ b/drivers/gpu/nvgpu/include/nvgpu/timers.h
@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) 2016, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __NVGPU_TIMERS_H__
+#define __NVGPU_TIMERS_H__
+
+struct gk20a;
+
+/*
+ * struct nvgpu_timeout - define a timeout.
+ *
+ * There are two types of timer suported:
+ *
+ *   o  NVGPU_TIMER_CPU_TIMER
+ *        Timer uses the CPU to measure the timeout.
+ *
+ *   o  NVGPU_TIMER_RETRY_TIMER
+ *        Instead of measuring a time limit keep track of the number of times
+ *        something has been attempted. After said limit, "expire" the timer.
+ *
+ * Available flags:
+ *
+ *   o  NVGPU_TIMER_NO_PRE_SI
+ *        By default when the system is not running on silicon the timeout
+ *        code will ignore the requested timeout. Specifying this flag will
+ *        override that behavior and honor the timeout regardless of platform.
+ *
+ *   o  NVGPU_TIMER_SILENT_TIMEOUT
+ *        Do not print any messages on timeout. Normally a simple message is
+ *        printed that specifies where the timeout occurred.
+ */
+struct nvgpu_timeout {
+        struct gk20a            *g;
+
+        unsigned int             flags;
+
+        union {
+                unsigned long    time;
+                struct {
+                        int      max;
+                        int      attempted;
+                } retries;
+        };
+};
+
+/*
+ * Bit 0 specifies the type of timer: CPU or retry.
+ */
+#define NVGPU_TIMER_CPU_TIMER           (0x0)
+#define NVGPU_TIMER_RETRY_TIMER         (0x1)
+
+/*
+ * Bits 1 through 7 are reserved; bits 8 and up are flags:
+ */
+#define NVGPU_TIMER_NO_PRE_SI           (0x1 << 8)
+#define NVGPU_TIMER_SILENT_TIMEOUT      (0x1 << 9)
+
+#define NVGPU_TIMER_FLAG_MASK           (NVGPU_TIMER_RETRY_TIMER |      \
+                                         NVGPU_TIMER_NO_PRE_SI |        \
+                                         NVGPU_TIMER_SILENT_TIMEOUT)
+
+int nvgpu_timeout_init(struct gk20a *g, struct nvgpu_timeout *timeout,
+                       int duration, unsigned long flags);
+int nvgpu_timeout_peek(struct nvgpu_timeout *timeout);
+
+#define nvgpu_timeout_check(__timeout)                                  \
+        __nvgpu_timeout_check_msg(__timeout,                            \
+                                  __builtin_return_address(0), "")
+
+#define nvgpu_timeout_check_msg(__timeout, fmt, args...)                \
+        __nvgpu_timeout_check_msg(__timeout,                            \
+                                  __builtin_return_address(0),          \
+                                  fmt, ##args)
+
+/*
+ * Don't use this directly.
+ */
+int __nvgpu_timeout_check_msg(struct nvgpu_timeout *timeout,
+                              void *caller, const char *fmt, ...);
+
+#endif