Quoting Ville Syrjälä (2018-02-02 17:44:58) > On Fri, Feb 02, 2018 at 05:31:57PM +0000, Chris Wilson wrote: > > I think we're okay with just using the master IIR for IRQ_NONE / > > IRQ_HANDLED as that is the interrupt generator aiui. If the child > > sources disagree that's another issue, but as far as the kernel is > > concerned i915 did generate and handle an interrupt. > > I think that might be the usual way it goes. I guess the IIR clearing is > racing with the MASTER_IRQ read as AFAIK the MASTER_IRQ status bits aren't > latched or anything (since we don't have to clear them). So I believe this > still leaves open a small window where even the MASTER_IRQ has cleared > itself by the time the irq handler gets around to reading it. So that > would look like a genuine spurious interrupt even though the GPU did > raise it for a reason. I've committed ourselves (for the time being at least) to always returning IRQ_HANDLED if the master IIR reports an interrupt. Hopefully I won't regret it :) Thanks, -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
