Re: i915_driver_irq_handler: irq 42: nobody cared

Daniel Vetter
2012-04-10T08:57:30Z

On Tue, Apr 10, 2012 at 10:47:49AM +0200, Jiri Slaby wrote:
> On 04/09/2012 07:11 PM, Jesse Barnes wrote:
> > On Fri, 30 Mar 2012 11:45:43 +0100 Chris Wilson
> > <chris@chris-wilson.co.uk> wrote:
> >
> >> On Fri, 30 Mar 2012 11:59:28 +0200, Jiri Slaby <jslaby@suse.cz>
> >> wrote:
> >>> I don't know what to dump more, because iir is obviously zero
> >>> too. What other sources of interrupts are on the (G33) chip?
> >>
> >> IIR is the master interrupt, with chained secondary interrupt
> >> statuses. If IIR is 0, the interrupt wasn't raised by the GPU.
> >
> > I've actually seen cases where one of the PIPE*STAT regs is stuck,
> > and even if IIR is 0 we still get interrupts... Jiri can you verify
> > the PIPE*STAT regs have bits set, maybe one or more we don't check
> > for?
>
> Note that I already attached their contents... This is what is in them
> (pipes 0 and 1):
> [ 3572.968581] i915_driver_irq_handler: 0=00000000 1=00000000
> [ 3572.977472] i915_driver_irq_handler: 0=00000000 1=00000000
> [ 3576.224839] i915_driver_irq_handler: 0=00000000 1=00000000
> [ 3576.243558] i915_driver_irq_handler: 0=00000000 1=00000000
> [ 3576.384912] i915_driver_irq_handler: 0=00000000 1=00000000
> [ 3576.403462] i915_driver_irq_handler: 0=00000000 1=00000000
> [ 3577.464100] i915_driver_irq_handler: 0=00000000 1=00000000
> [ 3577.477383] i915_driver_irq_handler: 0=00000000 1=00000000
> [ 3577.829016] i915_driver_irq_handler: 0=00020000 1=00000000
> [ 3577.830093] i915_driver_irq_handler: 0=00020000 1=00000000
>
> I.e. the handler is called when IIR=0 and both pipe stats are 0.

Hm, can you also dump the PORT_HOTPLUG_STAT register? That's the only
other subordinate interrupt source left.
-Daniel
--
Daniel Vetter
Mail: daniel@ffwll.ch
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