gpu: nvgpu: add tests for circ_buf

Add unit tests for posix circ_buf unit.

Jira NVGPU-4417

Change-Id: Ic0b04961cdd7813aed6f9b16fd0724b0e3cfeb2a
Signed-off-by: ajesh <akv@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvgpu/+/2287141
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>

userspace/units/posix/circ_buf/posix-circbuf.h

@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 2020, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+/**
+ * @addtogroup SWUTS-posix-circbuf
+ * @{
+ *
+ * Software Unit Test Specification for posix-circbuf
+ */
+
+#ifndef UNIT_POSIX_CIRCBUF_H
+#define UNIT_POSIX_CIRCBUF_H
+
+/**
+ * Test specification for test_circbufcnt
+ *
+ * Description: Test the buffer count implementation.
+ *
+ * Test Type: Feature
+ *
+ * Targets: CIRC_CNT
+ *
+ * Inputs: None
+ *
+ * Steps:
+ * 1) Invoke CIRC_CNT in loop with head assigned with loop index value and
+ *    tail as zero.
+ * 2) Check if the return value of buffer count is equal to loop index. Else
+ *    return fail.
+ * 3) Invoke CIRC_CNT in loop with head assigned as maximum index and tail
+ *    decreased according to the loop index value.
+ * 4) Check if the return value of buffer count is equal to loop index. Else
+ *    return fail.
+ * 5) Invoke CIRC_CNT with both head and tail assigned with same value.
+ * 6) Check if the return value is equal to zero, else return fail.
+ * 7) Return PASS.
+ *
+ * Output:
+ * The test returns PASS if all the invocations of CIRC_CNT returns the
+ * expected value as buffer count. Otherwise, test returns FAIL.
+ */
+int test_circbufcnt(struct unit_module *m, struct gk20a *g, void *args);
+
+/**
+ * Test specification for test_circbufspace
+ *
+ * Description: Test the buffer space check implementation.
+ *
+ * Test Type: Feature
+ *
+ * Targets: CIRC_SPACE
+ *
+ * Inputs: None
+ *
+ * Steps:
+ * 1) Invoke CIRC_SPACE in loop with head assigned as loop index and
+ *    tail as buffer size.
+ * 2) Check if the return value of buffer space is equal to the maximum
+ *    entries that the buffer can hold minus loop index. Else
+ *    return fail.
+ * 3) Return PASS.
+ *
+ * Output:
+ * The test returns PASS if all the invocations of CIRC_SPACE returns the
+ * expected value as available buffer space. Otherwise, test returns FAIL.
+ */
+int test_circbufspace(struct unit_module *m, struct gk20a *g, void *args);
+
+#endif /* UNIT_POSIX_CIRCBUF_H */