Re: /proc/pci design idea

Ralf Baechle (ralf@cobaltmicro.com)
Tue, 16 Sep 1997 13:02:12 -0700 (PDT)

> > only, but then it won't be usable as a general device (i.e., cat /dev/pci
> > won't work).
>
> Is it really that bad to have longword reads in PCI configuration space for
> byte/word registers?

Probably not. The chipset of the SNI RM200/RM300 machines only allows
32bit wide r/w access. For smaller reads the values have to be masked out,
for smaller writes you have to do rmw.

> For writes it's different. But writes can be restricted to 1, 2 or 4 bytes
> without much problems. Software that wants to write to /dev/pci has to know how
> to deal with PCI config space anyway.

Ralf