iBook G4 - wrong CPU speed?

[Nathan Whitehorn]

On 07/19/12 06:55, Torfinn Ingolfsen wrote:
> I just upgraded my iBook G4[1] to FreeBSD 9.1-prerelease.
>
> Before the upgrade, dmesg showed this for the CPU:
> cpu0: Motorola PowerPC 7447A revision 1.5, 713.92 MHz
> cpu0: Features 9c000000<PPC32,ALTIVEC,FPU,MMU>
> cpu0: HID0 8450c0bc<EMCP,TBEN,NAP,DPM,ICE,DCE,SGE,BTIC,LRSTK,FOLD,BHT>
>
> The upgrade took a long time, so I could believe it was running at that speed.
>
> And after the upgrade, it still shows this:
> root at kg-ibook# uname -a
> FreeBSD kg-ibook.kg4.no 9.1-PRERELEASE FreeBSD 9.1-PRERELEASE #0: Thu Jul 19 11:26:56 CEST 2012
>      root at kg-ibook.kg4.no:/usr/obj/usr/src/sys/GENERIC  powerpc
> root at kg-ibook# dmesg | grep cpu
> cpu0: Motorola PowerPC 7447A revision 1.5, 713.92 MHz
> cpu0: Features 9c000000<PPC32,ALTIVEC,FPU,MMU>
> cpu0: HID0 8450c0bc<EMCP,TBEN,NAP,DPM,ICE,DCE,SGE,BTIC,LRSTK,FOLD,BHT>
> cpulist0: <Open Firmware CPU Group> on nexus0
> cpu0: <Open Firmware CPU> on cpulist0
> dfs0: <Dynamic Frequency Switching> on cpu0
>
> But the CPU in this thing is supposedly running at 1.42 GHz, so why is it showing the wrong speed?
> Details, dmesg output and more at the FreeBSD page for this machine[2].
>
> References:
> 1) http://sites.google.com/site/tingox/ibook_g4
> 2) http://sites.google.com/site/tingox/ibook_g4_freebsd

iBooks boot with the CPU at half speed. You can turn it back up 
automatically (and control it based on load for power savings) by 
running powerd or alternately set it by hand using the sysctl 
dev.cpu.0.freq.
-Nathan