[parisc-linux] sched_clock implementation

[Carlos O'Donell]

On Sun, Sep 21, 2003 at 01:20:36PM +0200, Helge Deller wrote:
> On Sunday 21 September 2003 02:04, Grant Grundler wrote:
> > On Sat, Sep 20, 2003 at 06:02:10PM +0000, Joel Soete wrote:
> > > a quick look into paxx.pdf which about CR16 speak of "peak instruction
> > > rate" but do not define anywhere?
> > > I presume that is the cpu clock but would like somebody confirm.
> >
> > Read about "Interval Timer" (cr16) in the PA 2.0 Arch book.
> > PDC provides the exact rate that CR16 is changing.
> > Looks like PDC_TOD_ITIMER is the call but I'm not sure offhand.
> > In any case, I've only seen it used as CPU cycle counter.
> > (ie 1:1 with CPU clock).
> 
> Hi Joel,
> 
> I think we have the rate in the variable "boot_cpu_data.cpu_hz" (see 
> arch/parisc/kernel/processor.c) already.

Technically that's our highest precision timer :)

c.