From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Daniel Palmer <me@danielpalmer.co.uk>
Cc: linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: PATA_ARTOP reads byte from PCI IO port without mapping it to the right address.
Date: Wed, 30 Mar 2011 21:24:40 +0100 [thread overview]
Message-ID: <20110330212440.794e85de@lxorguk.ukuu.org.uk> (raw)
In-Reply-To: <4D93890A.60307@danielpalmer.co.uk>
On Wed, 30 Mar 2011 20:48:26 +0100
Daniel Palmer <me@danielpalmer.co.uk> wrote:
>
> > That is the PCI port address.
>
> I don't pretend to understand most of this fully.
> On the board the PCI address space/PCI controller is apparently at
> 0xfe240000
> So I guess that when that byte is read it should read from 0xfe240000 +
> 0x1400?
> That doesn't happen and a read happens at 0x1400 and an oops results.
> I don't know enough to point the finger really.
>
> There are probably only 2 people using this board still too. So I doubt
> it really matters. :)
That sounds like the inb() function has been broken by a change perhaps
by some related board change - if your I/O is mapped as you describe I'd
expect inb() to be implemented as something like
return *(volatile u8 *)(0xfe2400 + addr)
Might be worth bisecting between a good and bad release as it ought to be
easy to find
Alan
prev parent reply other threads:[~2011-03-30 20:24 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-30 19:09 PATA_ARTOP reads byte from PCI IO port without mapping it to the right address Daniel Palmer
2011-03-30 19:26 ` Alan Cox
2011-03-30 19:36 ` Linus Torvalds
2011-03-30 19:48 ` Daniel Palmer
2011-03-30 20:00 ` Arnd Bergmann
2011-03-30 20:24 ` Daniel Palmer
2011-03-30 20:37 ` Arnd Bergmann
2011-03-30 20:24 ` Alan Cox [this message]
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