[RFC PATCH 02/12] ARM: smp_twd: add support for remapped PPI interrupts

[Marc Zyngier]

On Mon, 25 Apr 2011 10:04:17 -0700
Stephen Boyd <sboyd at codeaurora.org> wrote:

Hi Stephen,

> On 4/20/2011 12:08 PM, Marc Zyngier wrote:
> > diff --git a/arch/arm/include/asm/entry-macro-multi.S b/arch/arm/include/asm/entry-macro-multi.S
> > index ec0bbf7..c599795 100644
> > --- a/arch/arm/include/asm/entry-macro-multi.S
> > +++ b/arch/arm/include/asm/entry-macro-multi.S
> > @@ -24,7 +24,7 @@
> >  	adrne	lr, BSYM(1b)
> >  	bne	do_IPI
> >  
> > -#ifdef CONFIG_LOCAL_TIMERS
> > +#if defined(CONFIG_LOCAL_TIMERS) && !defined(CONFIG_ARM_GIC_VPPI)
> >  	test_for_ltirq r0, r6, r5, lr
> >  	movne	r0, sp
> >  	adrne	lr, BSYM(1b)
> > diff --git a/arch/arm/include/asm/hardware/entry-macro-gic.S b/arch/arm/include/asm/hardware/entry-macro-gic.S
> > index c115b82..14a3363 100644
> > --- a/arch/arm/include/asm/hardware/entry-macro-gic.S
> > +++ b/arch/arm/include/asm/hardware/entry-macro-gic.S
> > @@ -17,23 +17,26 @@
> >  	.endm
> >  #endif
> >  
> > +#ifdef CONFIG_ARM_GIC_VPPI
> > +#define DO_IRQ_BASE	16
> > +#else
> > +#define DO_IRQ_BASE	30
> > +#endif
> > +
> >  /*
> >   * The interrupt numbering scheme is defined in the
> >   * interrupt controller spec.  To wit:
> >   *
> >   * Interrupts 0-15 are IPI
> > - * 16-28 are reserved
> > - * 29-31 are local.  We allow 30 to be used for the watchdog.
> > + * 16-31 are local.  We allow 30 to be used for the watchdog.
> >   * 32-1020 are global
> >   * 1021-1022 are reserved
> >   * 1023 is "spurious" (no interrupt)
> >   *
> > - * For now, we ignore all local interrupts so only return an interrupt if it's
> > - * between 30 and 1020.  The test_for_ipi routine below will pick up on IPIs.
> > - *
> >   * A simple read from the controller will tell us the number of the highest
> >   * priority enabled interrupt.  We then just need to check whether it is in the
> > - * valid range for an IRQ (30-1020 inclusive).
> > + * valid range for an IRQ (30-1020 inclusive). If CONFIG_ARM_GIC_VPPI is
> > + * enabled, local interrupts are handled the same way as global ones.
> >   */
> >  
> >  	.macro  get_irqnr_and_base, irqnr, irqstat, base, tmp
> > @@ -43,7 +46,7 @@
> >  
> >  	ldr	\tmp, =1021
> >  	bic     \irqnr, \irqstat, #0x1c00
> > -	cmp     \irqnr, #29
> > +	cmp     \irqnr, #(DO_IRQ_BASE - 1)
> >  	cmpcc	\irqnr, \irqnr
> >  	cmpne	\irqnr, \tmp
> >  	cmpcs	\irqnr, \irqnr
> > @@ -63,6 +66,7 @@
> >  	cmpcs	\irqnr, \irqnr
> >  	.endm
> >  
> > +#ifndef CONFIG_ARM_GIC_VPPI
> >  /* As above, this assumes that irqstat and base are preserved.. */
> >  
> >  	.macro test_for_ltirq, irqnr, irqstat, base, tmp
> > @@ -73,3 +77,4 @@
> >  	streq	\irqstat, [\base, #GIC_CPU_EOI]
> >  	cmp	\tmp, #0
> >  	.endm
> > +#endif
> 
> I would expect these bits to be part of the first patch in this series
> because they're necessary to actually use the CONFIG_ARM_GIC_VPPI
> option. Can you move them to the first patch?

I'd tend to agree with you, though local timer being the only user of
PPIs, it doesn't matter that much... ;-)

I'll move these changes to the first patch on the next iteration of the
patch set.

Thanks,

	M.
-- 
I'm the slime oozin' out from your TV set...