Fwd: TiBook CPU speed

[Justin Hibbits]

D'oh, didn't hit 'Reply All'.

---------- Forwarded message ----------
From: Justin Hibbits <jrh29 at alumni.cwru.edu>
Date: Tue, Sep 20, 2011 at 9:32 AM
Subject: Re: TiBook CPU speed
To: Nathan Whitehorn <nwhitehorn at freebsd.org>


On Tue, Sep 20, 2011 at 2:23 AM, Nathan Whitehorn <nwhitehorn at freebsd.org>wrote:

> On 09/20/11 05:07, Justin Hibbits wrote:
>
>> Following up on my previous email, the saga of installing FreeBSD on a
>> TiBook, I ran into another problem: The CPU speed is reduced to 666MHz,
>> instead of 1GHz. Is there a way to get it to run at the full 1GHz?
>>
>>
> Just use cpufreq(4) -- the dev.cpu.0.freq sysctl or turn on powerd.
> -Nathan
>

I looked at that first, but the MPC7455 doesn't have frequency scaling.  I
looked at the Linux and Darwin sources after reading a linux page that you
have to explicitly tell it to go full speed, and it turns out it's a PMU
command, and requires a CPU reset, and there are two OFW properties under
/cpu, min-clock-frequency and max-clock-frequency.

- Justin