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Date: Tue, 03 Jul 2001 04:31:25 -0400
From: Jeff Garzik <jgarzik@mandrakesoft.com>
Organization: MandrakeSoft
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To: David Howells <dhowells@redhat.com>
Cc: Russell King <rmk@arm.linux.org.uk>, Alan Cox <alan@lxorguk.ukuu.org.uk>,
        David Woodhouse <dwmw2@infradead.org>, Jes Sorensen <jes@sunsite.dk>,
        linux-kernel@vger.kernel.org, arjanv@redhat.com
Subject: Re: [RFC] I/O Access Abstractions
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I also point out that using ioremap for PIO adds flexibility while
keeping most drivers relatively unchanged.  Everyone uses a base address
anyway, so whether its obtained directly (address from PCI BAR) or
indirectly (via ioremap), you already store it and use it.

Further, code lacking ioremap for PIO (100% of PIO code, at present)
does not require a flag day.  Drivers can be transitioned as foreign
arches start supporting ioremap for PIO... if ioremap is no-op on x86,
drivers continue to work on x86 before and after the update.  Assuming a
stored not hardcoded base address (common case), the only change to a
driver is in probe and remove, nowhere else.

-- 
Jeff Garzik      | "I respect faith, but doubt is
Building 1024    |  what gives you an education."
MandrakeSoft     |           -- Wilson Mizner