From mboxrd@z Thu Jan  1 00:00:00 1970
From: arnd@arndb.de (Arnd Bergmann)
Date: Fri, 28 Feb 2014 13:27:24 +0100
Subject: [PATCH 1/3] PCI: designware: add legacy PCI interrupt mapping
In-Reply-To: <1393589374.5225.9.camel@weser.hi.pengutronix.de>
References: <1393550394-11071-1-git-send-email-tharvey@gateworks.com>
 <5728262.sMhnqxGTXH@wuerfel>
 <1393589374.5225.9.camel@weser.hi.pengutronix.de>
Message-ID: <6315058.94ydMC9ka8@wuerfel>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Friday 28 February 2014 13:09:34 Lucas Stach wrote:
> Am Freitag, den 28.02.2014, 12:37 +0100 schrieb Arnd Bergmann:
> > On Friday 28 February 2014 12:27:36 Lucas Stach wrote:
> > The interrupt-map doesn't even look well-formed, since it refers to
> > a gic that has #interrupt-cells=<3>, but only has one cell with the
> > value. This clearly cannot work at all. It should probably be
> > 
> >       interrupt-map = <0x0 0 &gic GIC_SPI 21 IRQ_TYPE_LEVEL_HIGH>;
> > 
> > Note that '53' is the IRQ number that is commonly assigned to
> > SPI interrupt 21, since SPI starts at number 32 on GIC.
> > 
> Ah, I see. Thanks for the explanation. So we have a bogus Exynos DT,
> which will break existing systems once the kernel starts to do the right
> thing. This is starting to look great. 
 
It seems tegra and r-car have the same bug. We can probably fix it
in a backwards-compatible way by changing the function to call
the generic helper first and if that fails call printk_once()
to emit a warning and return the hardwired IRQ number.

	Arnd