u-boot/test/time_ut.c
Simon Glass 8271f5d4c3 test: Add a simple time test
Sometimes the time functions are incorrect due to bad time support on a
board. Add a unit test which tries to detect this.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-05-06 12:48:37 -06:00

137 lines
2.7 KiB
C

/*
* Copyright (c) 2015 Google, Inc
* Written by Simon Glass <sjg@chromium.org>
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <command.h>
#include <errno.h>
static int test_get_timer(void)
{
ulong base, start, next, diff;
int iter;
base = get_timer(0);
start = get_timer(0);
for (iter = 0; iter < 10; iter++) {
do {
next = get_timer(0);
} while (start == next);
if (start + 1 != next) {
printf("%s: iter=%d, start=%lu, next=%lu, expected a difference of 1\n",
__func__, iter, start, next);
return -EINVAL;
}
start++;
}
/*
* Check that get_timer(base) matches our elapsed time, allowing that
* an extra millisecond may have passed.
*/
diff = get_timer(base);
if (diff != iter && diff != iter + 1) {
printf("%s: expected get_timer(base) to match elapsed time: diff=%lu, expected=%d\n",
__func__, diff, iter);
return -EINVAL;
}
return 0;
}
static int test_timer_get_us(void)
{
ulong prev, next, min = 1000000;
long delta;
int iter;
/* Find the minimum delta we can measure, in microseconds */
prev = timer_get_us();
for (iter = 0; iter < 100; ) {
next = timer_get_us();
if (next != prev) {
delta = next - prev;
if (delta < 0) {
printf("%s: timer_get_us() went backwards from %lu to %lu\n",
__func__, prev, next);
return -EINVAL;
} else if (delta != 0) {
if (delta < min)
min = delta;
prev = next;
iter++;
}
}
}
if (min != 1) {
printf("%s: Minimum microsecond delta should be 1 but is %lu\n",
__func__, min);
return -EINVAL;
}
return 0;
}
static int test_time_comparison(void)
{
ulong start_us, end_us, delta_us;
long error;
ulong start;
start = get_timer(0);
start_us = timer_get_us();
while (get_timer(start) < 1000)
;
end_us = timer_get_us();
delta_us = end_us - start_us;
error = delta_us - 1000000;
printf("%s: Microsecond time for 1 second: %lu, error = %ld\n",
__func__, delta_us, error);
if (abs(error) > 1000)
return -EINVAL;
return 0;
}
static int test_udelay(void)
{
long error;
ulong start, delta;
int iter;
start = get_timer(0);
for (iter = 0; iter < 1000; iter++)
udelay(1000);
delta = get_timer(start);
error = delta - 1000;
printf("%s: Delay time for 1000 udelay(1000): %lu ms, error = %ld\n",
__func__, delta, error);
if (abs(error) > 100)
return -EINVAL;
return 0;
}
static int do_ut_time(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
int ret = 0;
ret |= test_get_timer();
ret |= test_timer_get_us();
ret |= test_time_comparison();
ret |= test_udelay();
printf("Test %s\n", ret ? "failed" : "passed");
return ret ? CMD_RET_FAILURE : CMD_RET_SUCCESS;
}
U_BOOT_CMD(
ut_time, 1, 1, do_ut_time,
"Very basic test of time functions",
""
);