Re: System clock runs too fast after 2.6.27 -> 2.6.28.1 upgrade

[Ingo Molnar <mingo@elte.hu>]

* Florian Fainelli <florian.fainelli@telecomint.eu> wrote:

> Le Saturday 24 January 2009 02:36:30 john stultz, vous avez écrit :
> > On Fri, Jan 23, 2009 at 3:04 AM, Ingo Molnar <mingo@elte.hu> wrote:
> > > * john stultz <johnstul@us.ibm.com> wrote:
> > >> I'd think this would ideally be more of a subarch in the config
> > >> selection like the AMD Elan is, so folks know it really is not just a
> > >> extra-support feature and in fact limits what hardware you can use the
> > >> resulting kernel on.
> > >
> > > a better solution is that if RDC is set [it is unset by default] we
> > > should turn PIT_TICK_RATE into a variable, defaulting it to 1193182. If a
> > > real RDC or ELAN system is running, that variable is changed during early
> > > bootup, in the init functions for those platforms.
> >
> > Took a quick look at this, and I don't see any detection code for
> > either RDC. The X86_ELAN config also has no conditionals, but maybe
> > the elan cpufreq code can help here.
> >
> > Florian: Is there any way we can check very early (ie: in setup_arch)
> > for an RDC box?
> 
> Sorry for answering so late.
> 
> We cannot rely on the cpuid since there is not one, nor the bios, since 
> most (if not all) boards use RedBoot as a bootloader. If we have PCI 
> initiliazed, we could check the presence of a R6040 Ethernet MAC.
> [...]

yep, an early PCI quirk for that would suffice.

	Ingo