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From: Arnd Bergmann <arnd@arndb.de>
To: Axel Lin <axel.lin@ingics.com>
Subject: Re: irqchip: sirfsoc: Question about SIRFSOC_NUM_IRQS setting
Date: Thu, 4 Jul 2013 17:29:43 +0200
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On Thursday 04 July 2013, Axel Lin wrote:
> irq_setup_generic_chip() setup max. 32 interrupts starting from gc->irq_base.
> 
> sirfsoc_irq_init()
>   -> sirfsoc_alloc_gc()
>     -> irq_setup_generic_chip()
> 
> In sirfsoc_irq_init(), current code calls
> sirfsoc_alloc_gc(base + 4, 32, SIRFSOC_NUM_IRQS - 32); //Note, SIRFSOC_NUM_IRQS is 128
> 
> So I'm wondering if SIRFSOC_NUM_IRQS setting is correct or not.

I think this is a result of the sirf marco platform getting added. Note
also the comment in

        /* using legacy because irqchip_generic does not work with linear */
        sirfsoc_irqdomain = irq_domain_add_legacy(np, SIRFSOC_NUM_IRQS, 0, 0,
                                 &irq_domain_simple_ops, base);


With linux-3.11 this is no longer true: the generic irqchip now does
work with the linear domain, and the code can be simplified by
using irq_alloc_domain_generic_chips(), which also gets rid
of the SIRFSOC_NUM_IRQS constant.

	Arnd