[PATCH 3/9] irq: convert generic-chip to use irq_domain

[robherring2@gmail.com (Rob Herring)]

On 12/14/2011 11:55 PM, Shawn Guo wrote:
> On Thu, Dec 15, 2011 at 01:25:20PM +0800, Shawn Guo wrote:
>> On Wed, Dec 14, 2011 at 09:28:52AM -0600, Rob Herring wrote:
>>> From: Rob Herring <rob.herring@calxeda.com>
>>>
>>> Add irq domain support to irq generic-chip. This enables users of
>>> generic-chip to support dynamic irq assignment needed for DT interrupt
>>> binding. Users must be converted to use irq_data.hwirq for determining
>>> local interrupt numbers rather than using the Linux irq number.
>>>
>>> irq_base is kept for now as there are a few users of it. Once they
>>> are converted to use the irq domain, it can be removed.
>>>
>>> Signed-off-by: Rob Herring <rob.herring@calxeda.com>
>>> Cc: Thomas Gleixner <tglx@linutronix.de>
>>> ---
>>
>> Tested-by: Shawn Guo <shawn.guo@linaro.org>
>>
> Sorry, I have to take that tag back after I correct my test setup.
> It does not work for imx5 TZIC case, because the following change
> I suggested before is missed.
> 
> diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
> index eb763f7..2a2aac1 100644
> --- a/kernel/irq/irqdomain.c
> +++ b/kernel/irq/irqdomain.c
> @@ -39,7 +39,7 @@ void irq_domain_add(struct irq_domain *domain)
>                         return;
>                 }
>                 d->domain = domain;
> -               d->hwirq = hwirq;
> +               d->hwirq = hwirq - domain->hwirq_base;

This is a problem. It entirely defeats the point of hwirq_base and it
would break the GIC. We need to fix this in the generic irq chip.

Rob

>         }
> 
>         mutex_lock(&irq_domain_mutex);
>