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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Jeff Garzik <jgarzik@mandrakesoft.com>
Cc: <linuxppc-dev@lists.linuxppc.org>, <linux-kernel@vger.kernel.org>
Subject: Re: The IO problem on multiple PCI busses
Date: Sat, 3 Mar 2001 18:28:08 +0100
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>I/O is not supposed to be fast, that's what MMIO is for. :)  Just do
>
>void outb (u8 val, u16 addr)
>{
>	void *addr = ioremap (ISA_IO_BASE + addr);
>	if (addr) {
>		writeb (val, addr);
>		iounmap (addr);
>	}
>}
>
>You can map and unmap for each call :)  Ugly and slow, but hey, it's
>I/O...

Well, that would really suck ;) And I don't think it would be necessary
as we can probably limit each IO bus to 64k without much problem, and
have them permanently ioremap'ed.

Ben.
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