From mboxrd@z Thu Jan  1 00:00:00 1970
From: catalin.marinas@arm.com (Catalin Marinas)
Date: Thu, 29 Jan 2015 15:29:23 +0000
Subject: [PATCH v7 13/17] ARM64 / ACPI: Add GICv2 specific ACPI boot
 support
In-Reply-To: <CACxGe6vb8au6sc0gDMDu4kuzmYBCuOrcObWkbj1mDoCGTgVLVw@mail.gmail.com>
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 <54B8F2E3.80306@arm.com>
 <CACxGe6tBb8L8upS3zenZbrOc_c0E=MA=DqLjkSezEbregaAaaA@mail.gmail.com>
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Message-ID: <20150129152922.GG8951@e104818-lin.cambridge.arm.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Tue, Jan 27, 2015 at 04:12:08PM +0000, Grant Likely wrote:
> On Fri, Jan 16, 2015 at 2:37 PM, Marc Zyngier <marc.zyngier@arm.com> wrote:
> >>>> @@ -78,6 +79,10 @@ void __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
> >>>>  void __init init_IRQ(void)
> >>>>  {
> >>>>     irqchip_init();
> >>>> +
> >>>> +   if (!handle_arch_irq)
> >>>> +           acpi_gic_init();
> >>>> +
> >>>
> >>> Why isn't this called from irqchip_init? It would seem like the logical
> >>> spot to probe an interrupt controller.
> >>
> >> What has been done here isn't an unusual choice. We've got stuff all
> >> over the kernel that may or may not be implemented depending on what
> >> the architecture supports. If the function call is renamed to
> >> acpi_init_irq(), are you content?
> >
> > My (full) suggestion was to do it like we've done it for DT, and I don't
> > think I varied much from this point of view. Yes, calling it
> > acpi_irq_init() would be a good start, and having the ACPI-compatible
> > irqchips to be self-probable even better.
> >
> > <lack-of-sleep-rant>
> >
> > Hell, if nobody beats me to it, maybe I'll just write that code, with
> > proper entry points in the various GIC drivers. Yes, this is
> > infrastructure. Maybe it is grossly overdesigned. But I really spend too
> > much time dealing with the crap that people are happy to pile on top of
> > the GIC code to be madly enthusiastic about the general "good enough"
> > attitude.
> >
> > </lack-of-sleep-rant>
> >
> > Or to put it in a slightly more diplomatic way: If ACPI is to be our
> > future, can we please make the future look a bit better?
> 
> Hi Marc,
> 
> As per our off-list discussion, I completely agree. We don't want to
> be adding hack upon hack, and I will be first in line to NAK any
> patches taking that approach. However, for this initial series, it
> only supports exactly one GIC that can be set up by ACPI. Can we agree
> to leave it as is in this series, with the agreement that it will be
> replaced for v2m and v3 support with a proper pluggable initializer?

Can we at least call it acpi_init_irq() and avoid #including
gic-specific header files? IOW hide the apci_gic_init() behind some
generically named macro until the full solution is in place.

-- 
Catalin