Subject: [PATCH 2/4] ARM: OMAP2/3: intc: Add DT support for TI interrupt controller

From: [email-masked] (Rob Herring)
Date: Thu, 15 Dec 2011 14:52:02 -0600

On 12/15/2011 11:49 AM, Cousson, Benoit wrote:
> On 12/9/2011 5:12 PM, Rob Herring wrote:
>> On 12/09/2011 10:06 AM, Cousson, Benoit wrote:
> 
> [...]
> 
>>> My point is that even in the DT case I do have some devices that are
>>> initialized without DT for the moment and thus cannot get access to the
>>> interrupt-controller node and then cannot retrieve the domain information.
>>>
>>> How can I ensure the proper hwirq ->  irq translation then for such devices?
>>> Only the one created by DT will have the correct irq number.
>>
>> Okay, I missed that aspect of it. So I guess 0 base is fine for now.
>>
>> Rob
> 
> Following that discussion, I made a patch (included below) last week to add domain support just before this one for DT migration.
> I'm now wondering if it makes sense to do it like that considering your recent patch: irq: convert generic-chip to use irq_domain.
> 
> What do you think?

Using my patch should definitely simplify yours. You'll definitely need
the fix I discussed with Shawn. Also, I do have to sort out that it
breaks on x86 with Grant's suggested change, but that's not too complicated.

Rob

> 
> Thanks,
> Benoit
> 
> ---
> From 3083589f48604aab3d801179810c2af8339525ae Mon Sep 17 00:00:00 2001
> From: Benoit Cousson <[email-masked]>
> Date: Thu, 8 Dec 2011 22:16:51 +0100
> Subject: [PATCH] ARM: OMAP2/3: intc: Add irqdomain support
> 
> Introduce the usage of the irqdomain to prepare the DT support.
> The irq_base is still hard coded to 0 to allow non-DT drivers
> to work with the previous assumption that was hwirq = irq.
> 
> Signed-off-by: Benoit Cousson <[email-masked]>
> Cc: Tony Lindgren <[email-masked]>
> Cc: Rob Herring <[email-masked]>
> ---
>  arch/arm/mach-omap2/irq.c |   18 +++++++++++++++++-
>  1 files changed, 17 insertions(+), 1 deletions(-)
> 
> diff --git a/arch/arm/mach-omap2/irq.c b/arch/arm/mach-omap2/irq.c
> index 42b1d65..2f65dfd 100644
> --- a/arch/arm/mach-omap2/irq.c
> +++ b/arch/arm/mach-omap2/irq.c
> @@ -17,6 +17,7 @@
>  #include <mach/hardware.h>
>  #include <asm/exception.h>
>  #include <asm/mach/irq.h>
> +#include <linux/irqdomain.h>
>  
>  
>  /* selected INTC register offsets */
> @@ -57,6 +58,8 @@ static struct omap_irq_bank {
>  	},
>  };
>  
> +static struct irq_domain domain;
> +
>  /* Structure to save interrupt controller context */
>  struct omap3_intc_regs {
>  	u32 sysconfig;
> @@ -158,6 +161,17 @@ static void __init omap_init_irq(u32 base, int nr_irqs)
>  	if (WARN_ON(!omap_irq_base))
>  		return;
>  
> +	/*
> +	 * XXX: Use a 0 irq_base for the moment since the legacy devices
> +	 * created statically are expected a hwirq = irq mapping.
> +	 * A proper offset will be added later, when IRQ resource creation
> +	 * will be handled by DT.
> +	 */
> +	domain.irq_base = 0;
> +	domain.nr_irq = nr_irqs;
> +	domain.ops = &irq_domain_simple_ops;
> +	irq_domain_add(&domain);
> +
>  	for (i = 0; i < ARRAY_SIZE(irq_banks); i++) {
>  		struct omap_irq_bank *bank = irq_banks + i;
>  
> @@ -225,8 +239,10 @@ out:
>  		irqnr = readl_relaxed(base_addr + INTCPS_SIR_IRQ_OFFSET);
>  		irqnr &= ACTIVEIRQ_MASK;
>  
> -		if (irqnr)
> +		if (irqnr) {
> +			irqnr = irq_domain_to_irq(&domain, irqnr);
>  			handle_IRQ(irqnr, regs);
> +		}
>  	} while (irqnr);
>  }
>