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SubjectRe: PCI code: why need outb (0x01, 0xCFB); ?
On  8 Jan 03 at 10:52, H. Peter Anvin wrote:
> > 1. which device is at port address 0xCFB?
> Hopefully none.

Actually I'm not sure. This code is here since at least 2.0.28,
and during googling I even found code for direct PCI access
which sets lowest bit at 0xCFB to 1 before doing PCI config
accesses and reset it back to original value afterward.

So I believe that there were some chipsets (probably in 486&PCI times)
which did conf1/conf2 accesses depending on value of this bit.
Unfortunately I was not able to confirm this - almost nobody provides
northbridge datasheets from '94 era, even Intel does not provide them
(f.e. Neptune) anymore :-(
Best regards,
Petr Vandrovec

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