Re: [LinuxBIOS] lpci_set_subsystem question

[Segher Boessenkool]

> > Shouldn't the PCI config register always be 0x2c (subsystem ID 
> > register)
> > like in the last example (bcm5780_sb_pci_main.c)? Should these 
> > functions
> > even be there since there is a stock pci_dev_set_subsystem() that 
> > seems
> > to be correct?
>
> IIRC it should be, but is not always. A lot of chips don't quite
> follow the spec, and this weird out-of-band setting of registers crops
> up. That's my take on it anyway.

The PCI spec only defines the "read" behaviour of the subsystem
config registers as far as I know.  Anything writing those regs
is just as non-standard (or moreso!) as something using special
regs is.

Segher