Re: i915_driver_irq_handler: irq 42: nobody cared

Michel Dänzer
2012-04-11T06:29:40Z

On Die, 2012-04-10 at 11:34 -0700, Jesse Barnes wrote:
> On Tue, 10 Apr 2012 20:11:29 +0200
> Jiri Slaby <jslaby@suse.cz> wrote:
>
> > On 04/10/2012 06:26 PM, Jesse Barnes wrote:
> > > So port hotplug is always reporting that port C has a hotplug
> > > interrupt though... If you write 0x3 back to it does the interrupt
> > > stop?
> >
> > I'm not sure I got it right. This doesn't help:
> > --- a/drivers/gpu/drm/i915/i915_irq.c
> > +++ b/drivers/gpu/drm/i915/i915_irq.c
> > @@ -1416,6 +1416,17 @@ static irqreturn_t
> > i915_driver_irq_handler(DRM_IRQ_ARGS)
> > iir = new_iir;
> > }
> >
> > + if (ret == IRQ_NONE) {
> > + u32 hp = I915_READ(PORT_HOTPLUG_STAT);
> > + if (hp) {
> > + I915_WRITE(PORT_HOTPLUG_STAT, hp);
> > + I915_READ(PORT_HOTPLUG_STAT);
> > + }
> > +
> > + if (printk_ratelimit())
> > + printk(KERN_DEBUG "%s: %.8x\n", __func__, hp);
> > +
> > + }
> >
> > return ret;
> > }
>
> Yeah that looks right, you still get 0x300?

You said 'If you write 0x3 back' above, but this code writes 0x300.
Which is right?

--
Earthling Michel Dänzer | http://www.amd.com
Libre software enthusiast | Debian, X and DRI developer