From mboxrd@z Thu Jan  1 00:00:00 1970
From: Russell King - ARM Linux <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
Subject: Re: [PATCHv2 02/10] ARM: vic: MULTI_IRQ_HANDLER handler
Date: Thu, 3 Nov 2011 13:31:02 +0000
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To: Linus Walleij <linus.walleij-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
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On Thu, Nov 03, 2011 at 02:00:15PM +0100, Linus Walleij wrote:
> On Thu, Nov 3, 2011 at 1:51 PM, Russell King - ARM Linux
> <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org> wrote:
> =

> > =A0 =A0 =A0 =A0stat =3D readl_relaxed(vic->base + VIC_IRQ_STATUS);
> > =A0 =A0 =A0 =A0while (stat) {
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0while (stat) {
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0irq =3D ffs(stat) - 1;
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0stat &=3D ~(1 << irq);
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0handle_irq(irq);
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0}
> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0stat =3D readl_relaxed(vic->base + VIC_I=
RQ_STATUS);
> > =A0 =A0 =A0 =A0}
> >
> > This ensures that we process all interrupts found pending before we
> > re-check for any new interrupts pending. =A0Arguably this is a much
> > fairer implementation (and may mean if things get irrevokably stuck,
> > things like sysrq via the console uart may still work.)
> =

> I really like the looks of this, Jamie can you do it like that?
> =

> Maybe some smallish comment about what's going on can be
> good for future generations reading that code...

Bear in mind that it gets a little more complex when you have more
than one VIC, because the outer loop should be across all VICs.