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Date: Mon, 20 Nov 2006 11:42:48 +0000
From: Alan <alan@lxorguk.ukuu.org.uk>
To: Stefan Roese <ml@stefan-roese.de>
Subject: Re: [PATCH] serial: Use real irq on UART0 (IRQ = 0) on PPC4xx systems
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On Mon, 20 Nov 2006 12:00:36 +0100
Stefan Roese <ml@stefan-roese.de> wrote:

> This patch fixes a problem seen on multiple 4xx platforms, where
> the UART0 interrupt number is 0. The macro "is_real_interrupt" lead
> on those systems to not use an real interrupt but the timer based
> implementation.

NAK.

Zero means "no interrupt" in the Linux space. If you have a physical IRQ
0 remap it to a convenient number (eg map IRQ's + 1, or stick it on the
end). The logical and physical IRQ numbering in Linux don't have to match
up - and given some platforms have IRQ numbering per bus and the like
clearly doesn't in many cases.