Hi, +marcheu On 26 November 2015 at 10:07, Daniel Vetter <daniel@xxxxxxxx> wrote: > On Wed, Nov 25, 2015 at 05:09:02PM +0530, Thulasimani, Sivakumar wrote: >> however good to explicitly check for this, >> following needs to be tested before sending in next patch/merge >> 1) MST displays verification (Ander's reported on first set of patches) >> 2) check behavior on sleep - resume (dave&danvet) >> 3) storm handling needs to be handled as well. (i assume this should be >> fine, >> but good to check explicitly) (danvet) >> > > Yeah the storm mitigation will keep on working. What I'm worried about is > that polling won't work any more: When a storm happens we disable the hpd > and switch all affected connectors completely to polling. Polling happens > through the probe helpers in drm_probe_helper.c, and that code exclusively > uses ->detect callbacks. Which means if we no longer re-probe in detect > (since we assume hpd works correctly) then this will break the storm > handling code. > > Simplest fix (but a bit a hack) would be to check whether polling is > enabled at the top of intel_hdmi_detect and if so execute a full probe. > And not just return the cached values. > > Note that storms are only a concern for HDMI, not DP (somehow DP hw is > less shit). Hmm, from what I understand it's a concern on DP as well. Maybe due to DP->HDMI converters which just pass HPD through? Google's Type-C -> DP cable crushes all short HPD events - breaking MST short pulses - which I assume wasn't for no reason: https://chromium.googlesource.com/chromiumos/platform/ec/+/master/board/dingdong/board.c#27 Cheers, Daniel _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
