> ....I suspect I am
missing something somewhere, but I can't find any references to cpu speed control for the MIPS processors, specically the au1x range.
The Au1xxx has a PLL that multiplies the incoming 12 MHz clock up to the internal frequency. Just be aware there are lots of peripheral clocks and bus clocks derived from this internal frequency. There is code in the kernel power management to allow changing the frequency during operation of Linux, but I don't know how well it works today as I have not tested that for quite some time.
Thanks.
-- Dan