On Mon, 2007-06-25 at 11:49 -0700, Kok, Auke wrote: > Alan Cox wrote: > > On Sun, 24 Jun 2007 20:19:18 -0700 > > Auke Kok <[EMAIL PROTECTED]> wrote: > > > >> Currently there are 97 occurrences where drivers need the pci > >> revision ID. We can do this once for all devices. Even the pci > >> subsystem needs the revision several times for quirks. The extra > >> u8 member pads out nicely in the pci_dev struct. > >> > >> Signed-off-by: Auke Kok <[EMAIL PROTECTED]> > > > > Seems worth caching yes. Care needed changing the other uses however > > that the revision isn't changeable on the hardware in some magic fashion. > > if that happens the device could also change pci ID... I don't think we can > guard against that kind of abuse anyway. While this is perfectly possible > (e.g. > network cards carrying this info in their eeproms), we should still be OK > with > the core patch, but the device driver itself needs to pull the information > manually from the device using the pci_get_config_byte() method.
the other thing btw is that this approach allows us to use quirks and the like to fix up "crap". Maybe a good rule-of-thumb (and as with any other rule of thumb there are exceptions): Drivers should NEVER touch the standard part of PCI config space without going through a specific PCI layer API for the value they want. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
