iBook - hacking power managment and the PMU possible?

[alex6z]

I was wondering if it is possible to do advanced things with power managment on an iBook.

Say for example, if I wanted to clock down the CPU and FSB, Turn off the display, the GPU. the USB controller and devices, Firewire and devices, the harddisk and controller, and the cdrom drive. The CPU, northbridge, memory, pci, ethernet, and PMU(adb, keyboard and touchpad) is all than would be still on. Is it possible to do this?

Also, is it possible to reverse engineer the PMU and it's firmware? It is so small and can't be terribly complicated. Is it possible to monitor the process that OSX uses to update the PMU firmware? Could you extract the firmware from the OSX image and run it in a microcontroller emulator?