Re: check & reprogram PCI BAR

[David Brownlee <abs%netbsd.org@localhost>]

2010/1/19 Manuel Bouyer <bouyer%antioche.eu.org@localhost>:
> 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 :)

[Cutting across from a concurrent thread on another list...]

It would be nice if the *FIXUP options could be made runtime
configurable, so they could be enabled by 'boot -c' - would allow
people to get at them from a stock GENERIC...