At least on VLV when forcing a new GT frequency by writing to the min/max freq sysfs entries the kernel doesn't wait until the new frequency settles, so the subsequent readback check might fail. To fix this wait until the current frequency is between the min/max values using a 10ms timeout. Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx> --- tests/pm_rps.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) diff --git a/tests/pm_rps.c b/tests/pm_rps.c index 101f65d..9ed2125 100644 --- a/tests/pm_rps.c +++ b/tests/pm_rps.c @@ -34,6 +34,7 @@ #include <fcntl.h> #include <signal.h> #include <errno.h> +#include <time.h> #include <sys/wait.h> #include "drmtest.h" @@ -87,6 +88,38 @@ static void read_freqs(int *freqs) freqs[i] = readval(stuff[i].filp); } +static void nsleep(unsigned long ns) +{ + struct timespec ts; + int ret; + + ts.tv_sec = 0; + ts.tv_nsec = ns; + do { + struct timespec rem; + + ret = nanosleep(&ts, &rem); + igt_assert(ret == 0 || errno == EINTR); + ts = rem; + } while (ret && errno == -EINTR); +} + +static void wait_freq_settle(void) +{ + int timeout = 10; + + while (1) { + int freqs[NUMFREQ]; + + read_freqs(freqs); + if (freqs[CUR] >= freqs[MIN] && freqs[CUR] <= freqs[MAX]) + break; + nsleep(1000000); + if (!timeout--) + break; + } +} + static int do_writeval(FILE *filp, int val, int lerrno) { int ret, orig; @@ -102,6 +135,7 @@ static int do_writeval(FILE *filp, int val, int lerrno) } else { /* Expecting no error */ igt_assert_neq(ret, 0); + wait_freq_settle(); igt_assert(readval(filp) == val); } -- 1.8.4 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx