From 8271f5d4c3a0ce8282025217509c18220a0f552b Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Sat, 2 May 2015 09:25:02 -0600 Subject: [PATCH] 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 --- test/Kconfig | 8 +++ test/Makefile | 1 + test/time_ut.c | 137 +++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 146 insertions(+) create mode 100644 test/time_ut.c diff --git a/test/Kconfig b/test/Kconfig index 1fb1716a4a..3270c84213 100644 --- a/test/Kconfig +++ b/test/Kconfig @@ -1 +1,9 @@ +config CMD_UT_TIME + bool "Unit tests for time functions" + help + Enables the 'ut_time' command which tests that the time functions + work correctly. The test is fairly simple and will not catch all + problems. But if you are having problems with udelay() and the like, + this is a good place to start. + source "test/dm/Kconfig" diff --git a/test/Makefile b/test/Makefile index 9c95805c44..08330e020c 100644 --- a/test/Makefile +++ b/test/Makefile @@ -6,3 +6,4 @@ obj-$(CONFIG_SANDBOX) += command_ut.o obj-$(CONFIG_SANDBOX) += compression.o +obj-$(CONFIG_CMD_UT_TIME) += time_ut.o diff --git a/test/time_ut.c b/test/time_ut.c new file mode 100644 index 0000000000..6b52245d7f --- /dev/null +++ b/test/time_ut.c @@ -0,0 +1,137 @@ +/* + * Copyright (c) 2015 Google, Inc + * Written by Simon Glass + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include +#include +#include + +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", + "" +); -- 2.39.5