or http://www.engadget.com/2007/11/14/n...-runs-on-n800/ overclock like an 810

I've been playing around and watching the CPU go up and down while performing various tasks, and it appears the builtin SIP client gets the CPU locked to 330mhz.

/sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
and /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
both get set to 330000.

I'd like to have it return to normal behavior after a call has ended, any suggestions, aside from reboot?

This is with OS2008 on an N800.

The DSP runs at it's maximum speed (220Mhz) only when the main CPU is running at 330Mhz - oddly enough the DSP runs at 133Mhz when the main CPU is clocked at 400Mhz. Assuming SIP utilises the DSP, that would explain why the CPU must be locked at 330Mhz while SIP is active, but once SIP is no longer running or actively using the DSP the frequency scaling should return to normal... if this isn't the case (have you tried exiting SIP completely?) I would suggest a bug is raised but since we're all using an OS that isn't officially designated for the N800 I'm not sure there's much point.

Link to a Nokia Power Management PDF which details the ARM core/DSP speed relationship on page 15.

In order for clocks to sync, there has to be some common multiplication factor (110, 133, etc). So 220 and 330 MHz components sync on 110, whereas in the latter example the multiple is 133 (133 x 3= 399 eg. 400 Mhz). I'm guessing there's no other factor available for 400 MHz in this case.

Yeah, I'd expect it to go back to normal after a call, but even after closing the app it stays at 330.

I don't think I'll file any bug reports until an official release comes out, so for now I'll just bug you guys on the forums

Edit: Tried playing an mp3 in Media player, since it also uses the DSP, and it puts everything back to normal right when the mp3 stops, unless I run it after placing a call through the SIP client.

Any suggestions on how to manually clock the DSP and CPU to pre-SIP-call values?

Rebooting to get back the fancy CPU scaling sucks

dblank: Just leave it alone! It will scale the frequency and voltage according to the needs of the system :-p

Also, at the risk of putting a dampner on your experimentation, you can't use arbitrary frequency values . There has to be corresponding kernel code that will map these values to the right register values to be programmed into the OMAP.

So wait for the kernel code and read up on DVFS in the meanwhile. ;-)

Not after making a call with the SIP client it won't.

It stays at 330mhz until a reboot, then it goes back to switching between 165 and 400 depending on the needs of the system.

I just want it to go back to the state it was in before making a call.

Report a bug?

Hi guys,

New here. Apologies for not reading any FAQ I upgraded my
N800 to OS2008. The upgrade was a breeze but mplayer is
seriously broken. Video lags behind audio by several seconds.
The same file was OK under OS2007. Also, the N800 FEELS VERY WARM The front panel(aluminium?) and the screen are warm to touch. I have switched it off because I am not sure whether it will cause damage.

Now, the question is how do I underclock? Is it max min freq. params under /proc? Is there any app that will do it?

Don t say : "I upgraded my N800 to OS2008."

But "I upgraded my N800 with a leaked firmware of OS2008 for n810".