IRQ #0 broken on ARM

[Rob Herring]

On Fri, Nov 21, 2014 at 3:32 PM, Robert Jarzmik <robert.jarzmik at free.fr> wrote:
> Marc Zyngier <marc.zyngier at arm.com> writes:
>>> Linus has decreed it to not be a valid IRQ number, and that's basically
>>> the end of the discussion.  Generic code, and drivers, will increasingly
>>> decide that IRQ0 is not valid, and objecting to it has, and will continue
>>> to elicit a response of "fix ARM".
>>
>> I'm fine with that.
> For pxa, why not do something like that [1] ?
>
> Cheers.
>
> --
> Robert
>
> [1]
> ---8>---
>
> From 551eaf75934bd84939a40781470ed3c04d17507a Mon Sep 17 00:00:00 2001
> From: Robert Jarzmik <robert.jarzmik at free.fr>
> Date: Fri, 21 Nov 2014 22:11:42 +0100
> Subject: [PATCH] ARM: pxa: arbitrarily set first interrupt number
>
> As IRQ0, the legacy timer interrupt should not be used as an interrupt
> number, shift the interrupts by a fixed number.
>
> As we had in a special case a shift of 16 when ISA bus was used on a
> PXA, use that value as the first interrupt number, regardless of ISA or
> not.
>
> Signed-off-by: Robert Jarzmik <robert.jarzmik at free.fr>
> ---
>  arch/arm/mach-pxa/include/mach/irqs.h | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/arch/arm/mach-pxa/include/mach/irqs.h b/arch/arm/mach-pxa/include/mach/irqs.h
> index 48c2fd8..9d8983f 100644
> --- a/arch/arm/mach-pxa/include/mach/irqs.h
> +++ b/arch/arm/mach-pxa/include/mach/irqs.h
> @@ -14,12 +14,9 @@
>
>  #ifdef CONFIG_PXA_HAVE_ISA_IRQS

You can get rid of this ifdef and kconfig symbol. It is only used here.

>  #define PXA_ISA_IRQ(x) (x)
> -#define PXA_ISA_IRQ_NUM        (16)
> -#else
> -#define PXA_ISA_IRQ_NUM        (0)
>  #endif
>
> -#define PXA_IRQ(x)     (PXA_ISA_IRQ_NUM + (x))
> +#define PXA_IRQ(x)     (16 + (x))

Perhaps use NR_IRQS_LEGACY here.

>  #define IRQ_SSP3       PXA_IRQ(0)      /* SSP3 service request */
>  #define IRQ_MSL                PXA_IRQ(1)      /* MSL Interface interrupt */
> --
> 2.1.0
>
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