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Re: check & reprogram PCI BAR

On Tue, Jan 19, 2010 at 12:57:30PM -0600, David Young wrote:
> On Tue, Jan 19, 2010 at 12:57:57PM +0100, Manuel Bouyer wrote:
> > On Tue, Jan 19, 2010 at 12:50:55PM +0100, Christoph Egger wrote:
> > > Why are the *FIXUP options disabled by default in x86 kernels?
> > 
> > Because on some systems it reprograms the BARs in a way which doesn't
> > work. I'm not sure the kernel can do this in a reasonable and safe
> > way anyway, it would need detailled knowledge of the hardware,
> > which may not be available.
> What detailed knowledge do you have in mind?

For example, device for which the kernel has no drivers, but still
have registers mapped in I/O or memory space.
I'm sure PC hardware also have a few fun things I don't know about :)

Manuel Bouyer <>
     NetBSD: 26 ans d'experience feront toujours la difference

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