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Subject: Re: Reverting old hack
From:   Benjamin Herrenschmidt <benh@kernel.crashing.org>
To:     Ralf Baechle <ralf@linux-mips.org>
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Date:   Thu, 25 Feb 2010 07:53:31 +1100
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On Wed, 2010-02-24 at 17:41 +0100, Ralf Baechle wrote:
> 
> The complicated solution is to reserve all address range that potencially
> could cause such aliases.  But with the PCI spec limiting port allocations
> for devices to a maximum of 256 bytes 16MB of port address space already is
> way more than one would ever expect to be used so I suggest to just limit
> the port address space to 16MB.
> 
> Could you test the patch below?

On PPC I set the top level IO resource to no more than 1M, actually even
as small as 64K on some bridges. There's no point doing more, x86 ony
have 64K of IO space anyways :-)

Cheers,
Ben.