tiBook CPU speed
I noticed this issue mentioned previously on this list, but there didn't
seem to be any resolution.
The 800MHz tiBook boots linux in 667MHz mode:
/proc/device-tree/cpus/PowerPC,G4
min-clock-frequency
0000000: 27c1 9cc0 '...
max-clock-frequency
0000000: 2faf 0800 /...
clock-frequency
0000000: 27c1 9cc0 '...
force-reduced-speed
0000000: 0000 0001 ....
I don't know if that last entry is a bitmask, or a state. I imagine that
if it's a state, I can just go and reset it in Open Firmware, and
everything will be OK, but for laptop users, being able to throttle the
CPU speed is really useful.
A cursory poke around the PPC 7455 docs on the motorola website seems to
indicate that the speed throttling isn't done with an MSR on the CPU. I
don't know where to look for good documentation about Open Firmware and
Apple hardware (any pointers?).
Toby.
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