[Intel-gfx] [PATCH 2/2] drm/i915: shut up gen8+ SDE irq dmesg noise

[Dave Gordon]

On 23/10/15 10:14, Daniel Vetter wrote:
> On Fri, Oct 23, 2015 at 10:03:50AM +0100, Chris Wilson wrote:
>> On Fri, Oct 23, 2015 at 10:56:12AM +0200, Daniel Vetter wrote:
>>> We get tons of cases where the master interrupt handler apparently set
>>> a bit, with the SDEIIR agreeing. No idea what's going on there, but
>>> it's consistent on gen8+, no one seems to care about it and it's
>>> making CI results flaky.
>>
>> Just delete the message and delete them all. There isn't anything we can
>> do and if anybody actually cared (which apparently they didn't in the
>> first place), they could just trace the mmio.
>
> The non-SDE ones don't fire and I think are useful. And in case we have
> another report from users that gmbus is not reliably working with their
> touchpad (this is how we discovered the original pch irq issues) I think
> finding some breadcrumbs in dmesg would be useful. The SDE one happens
> rarely enough that I don't think it should be a performance issue, ever.
>
> Hence why I decided to keep them.
> -Daniel

I used to get the "master interrupt lied" message quite frequently. 
Since it was not clear whether it really meant that the master had an 
extra bit set or that one (any) of the detail registers was missing an 
interrupt bit, I tried servicing the interrupt anyway. But it didn't 
help with any of the issues I was seeing at the time, and the message no 
longer occurs (on SKL) with more recent kernels.

.Dave.