mpc8xx - power save modes - PIT

[Patrick Mahoney]

Conn,

I noticed a couple of things...

1- If SCCR[PRQEN] is NOT set, your idle.c patch makes the current
consumption drop as expected, but the processor never wakes up, which
is normal, but not what we want.

2- If SCCR[PRQEN] IS set, your idle.c patch seems to put the processor
in doze mode at each loop, but the current consumption does not
drop. I printk'ed the 'jiffies' global variable immediately before and
immediately after the
	_nmask_and_or_msr(0, MSR_POW | MSR_EE);
instruction. The printed values are all distant of 3 or 4 jiffies,
which suuggests that the processor spends as much time in doze mode
than in high mode. But the current consumption stays the same...

Any idea?

Regards,



Pat Mahoney

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