From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [patch 2/2] 8250_pnp: register x86 COM ports at the conventional
 ttyS names
Date: Wed, 16 Jan 2008 15:42:08 -0500
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Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>, linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, Russell King <rmk+serial@arm.linux.org.uk>, Jeff Garzik <jeff@garzik.org>, Andrew Morton <akpm@linux-foundation.org>, Alan Cox <alan@lxorguk.ukuu.org.uk>

Bodo Eggert wrote:
> 
> BTW1: These addresses may be used to detect ports on non-standard addresses,
> but unfortunately they don't tell the IRQ.
> 
> BTW2: When I submitted a patch using the BIOS data area, I was told that it
> might not exist on systems booting from non-PC firmware. This claim was not
> yet backed with any knowledge, nor did anybody suggest a way to detect this
> situation.
> 

This is, of course, true.  It doesn't exactly help that some (most?) 
non-PC firmware at least mimic the BIOS data area.

In this particular case, there is some minor sanity-checking that can be 
done: the values should be nonzero and aligned 8.

	-hpa