mpc8xx - power save modes - PIT

[Patrick Mahoney]

> I've tried Conn's code, but I'm experiencing problems with PLPRCR[CSCR] as
> being 1 all the time after a rfi. I am also occasionally seeing MSR_POW set
> to 1 after the rfi return.

Well the 2.4 Linux kernel does not support runtime modifications to
the clock rate. So what's the point of playing with CSCR?

>
> I can work around this problem by setting PLPRCR[CSCR] = 0 and MSR_POW = 0
> after the rfi and this eventually works. But is this the solution? I'm also
> noticing no great decrease in power consumption even though I've only got a
> couple of (sleeping) processes. And it seems that there is (mostly) no time
> between entering Doze Low mode and the rfi which confirms the unsatisfactory
> power consumption figures.

I notice no decrease at all!  :(

I set both crqen and prqen in the bootloader. The idled routine gets
entered and executed repeatedly, but no decrease in current
consumption can be observed.


Pat Mahoney

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