Hi Harry, Am Dienstag, den 25.06.2019, 10:00 -0400 schrieb Harry Wentland: > arm32's udelay only allows values up to 2000 microseconds. msleep > does the trick for us here as there is no problem if this isn't > microsecond accurate and takes a tad longer. A "tad" longer in this case means likely double the intended wait. Please see "SLEEPING FOR ~USECS OR SMALL MSECS ( 10us - 20ms)" in Documentation/timers/timers-howto.txt. The sleep here should use usleep_range. In general the DC code seems to use quite a lot of the udelay busy waits. I doubt that many of those occurrences are in atomic context, so could easily use a sleeping wait. Digging further this seems to apply across amdgpu, not only DC. Regards, Lucas > Signed-off-by: Harry Wentland <harry.wentland@xxxxxxx> > --- > drivers/gpu/drm/amd/display/dc/core/dc_link.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c > b/drivers/gpu/drm/amd/display/dc/core/dc_link.c > index 4c31930f1cdf..f5d02f89b3f9 100644 > --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c > +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c > @@ -548,7 +548,7 @@ static void > read_edp_current_link_settings_on_detect(struct dc_link *link) > break; > } > > - udelay(8000); > + msleep(8); > } > > ASSERT(status == DC_OK); _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
