From 2aaa36e95ea586ad23edfcc1d474e8b735a4d1c3 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Mateusz=20Jo=C5=84czyk?= Date: Sat, 19 Feb 2022 08:27:13 +0100 Subject: [PATCH] selftests/rtc: continuously read RTC in a loop for 30s MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Some problems with reading the RTC time may happen rarely, for example while the RTC is updating. So read the RTC many times to catch these problems. For example, a previous attempt for my commit ea6fa4961aab ("rtc: mc146818-lib: fix RTC presence check") was incorrect and would have triggered this selftest. To avoid the risk of damaging the hardware, wait 11ms before consecutive reads. In rtc_time_to_timestamp I copied values manually instead of casting - just to be on the safe side. The 11ms wait period was chosen so that it is not a divisor of 1000ms. Signed-off-by: Mateusz Jończyk Cc: Alessandro Zummo Cc: Alexandre Belloni Cc: Shuah Khan Signed-off-by: Shuah Khan --- tools/testing/selftests/rtc/rtctest.c | 66 +++++++++++++++++++++++++++ tools/testing/selftests/rtc/settings | 2 +- 2 files changed, 67 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/rtc/rtctest.c b/tools/testing/selftests/rtc/rtctest.c index 66af608fb4c6..2b9d929a24ed 100644 --- a/tools/testing/selftests/rtc/rtctest.c +++ b/tools/testing/selftests/rtc/rtctest.c @@ -20,6 +20,8 @@ #define NUM_UIE 3 #define ALARM_DELTA 3 +#define READ_LOOP_DURATION_SEC 30 +#define READ_LOOP_SLEEP_MS 11 static char *rtc_file = "/dev/rtc0"; @@ -49,6 +51,70 @@ TEST_F(rtc, date_read) { rtc_tm.tm_hour, rtc_tm.tm_min, rtc_tm.tm_sec); } +static time_t rtc_time_to_timestamp(struct rtc_time *rtc_time) +{ + struct tm tm_time = { + .tm_sec = rtc_time->tm_sec, + .tm_min = rtc_time->tm_min, + .tm_hour = rtc_time->tm_hour, + .tm_mday = rtc_time->tm_mday, + .tm_mon = rtc_time->tm_mon, + .tm_year = rtc_time->tm_year, + }; + + return mktime(&tm_time); +} + +static void nanosleep_with_retries(long ns) +{ + struct timespec req = { + .tv_sec = 0, + .tv_nsec = ns, + }; + struct timespec rem; + + while (nanosleep(&req, &rem) != 0) { + req.tv_sec = rem.tv_sec; + req.tv_nsec = rem.tv_nsec; + } +} + +TEST_F_TIMEOUT(rtc, date_read_loop, READ_LOOP_DURATION_SEC + 2) { + int rc; + long iter_count = 0; + struct rtc_time rtc_tm; + time_t start_rtc_read, prev_rtc_read; + + TH_LOG("Continuously reading RTC time for %ds (with %dms breaks after every read).", + READ_LOOP_DURATION_SEC, READ_LOOP_SLEEP_MS); + + rc = ioctl(self->fd, RTC_RD_TIME, &rtc_tm); + ASSERT_NE(-1, rc); + start_rtc_read = rtc_time_to_timestamp(&rtc_tm); + prev_rtc_read = start_rtc_read; + + do { + time_t rtc_read; + + rc = ioctl(self->fd, RTC_RD_TIME, &rtc_tm); + ASSERT_NE(-1, rc); + + rtc_read = rtc_time_to_timestamp(&rtc_tm); + /* Time should not go backwards */ + ASSERT_LE(prev_rtc_read, rtc_read); + /* Time should not increase more then 1s at a time */ + ASSERT_GE(prev_rtc_read + 1, rtc_read); + + /* Sleep 11ms to avoid killing / overheating the RTC */ + nanosleep_with_retries(READ_LOOP_SLEEP_MS * 1000000); + + prev_rtc_read = rtc_read; + iter_count++; + } while (prev_rtc_read <= start_rtc_read + READ_LOOP_DURATION_SEC); + + TH_LOG("Performed %ld RTC time reads.", iter_count); +} + TEST_F_TIMEOUT(rtc, uie_read, NUM_UIE + 2) { int i, rc, irq = 0; unsigned long data; diff --git a/tools/testing/selftests/rtc/settings b/tools/testing/selftests/rtc/settings index a953c96aa16e..0c1a2075d5f3 100644 --- a/tools/testing/selftests/rtc/settings +++ b/tools/testing/selftests/rtc/settings @@ -1 +1 @@ -timeout=180 +timeout=210