Quoting Daniel Vetter (2018-10-19 09:22:15) > On Mon, Oct 15, 2018 at 12:17:41PM +0100, Chris Wilson wrote: > > If the user passes i915.disable_display=1 we want to disable all the > > displays and associated HW like the powerwells on their behalf. Instead > > of short circuiting the HW probe, let it run and setup all the > > bookkeeping for the known HW. Afterwards, instead of taking over the > > BIOS fb and installing the fbcon, we shutdown all the outputs and > > teardown the bookkeeping, leaving us with no attached outputs or crtcs, > > and all the HW powered down. > > > > Open: wq flushes should be required but seem to deadlock the modprobe > > under CI. > > > > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > > Cc: Imre Deak <imre.deak@xxxxxxxxx> > > Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > i915.disable_display was for those server chips where doing all the init > resulted in a dead machine. So not sure we want this. For those server chips, we don't use i915.disable_display but detect when the fuses are lies and directly set num_pipes == 0. If we had such a machine in CI, you would already have seen a lot of the fun with KMS being allowed without any backing hw. Hence why Ville suggested we disable KMS for machines without pipes to avoid having to add a lot of defense around the driver. > What's the issue with power wells still being on and all that? On real hw > without display they won't exist, and I don't understand why we'd care for > testing. For testing. We do use .disable_display and expect rpm to still work, and to not get random display related failures interfering in displayless tests. Quite clearly we haven't been testing the displayless setups at all. -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
