Confusing about xm cpu speed in ubuntu

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1

I am running ubuntu-10.10-r1-minimal-armel.tar.7z from
http://elinux.org/BeagleBoardUbuntu. The cpu speed is supposed to be
800MHz, since boot.scr set mpurate 800. However, cpuinfo shows
BogoMIPS is 675.36, while demesg shows running at 800MHz. My question
is, is my xm actually running at 675MHz? How could I speed it up to
800MHz? What if I change mpurate to 1000 in boot.cmd and run the
script to make it boot.scr? Hope some guide before I actually change
this setting.

See the cpuinfo and dmesg output below

2

I am running ubuntu-10.10-r1-minimal-armel.tar.7z from
BeagleBoardUbuntu - eLinux.org. The cpu speed is supposed to be
800MHz, since boot.scr set mpurate 800. However, cpuinfo shows
BogoMIPS is 675.36, while demesg shows running at 800MHz. My question
is, is my xm actually running at 675MHz? How could I speed it up to
800MHz?

Yeap, that's just the speed the kernel reports when you give it 'mpurate=800'

What if I change mpurate to 1000 in boot.cmd and run the
script to make it boot.scr? Hope some guide before I actually change
this setting.

Oh you can change it to anything you want... but without the digital
voltage scaling patches anything above 800Mhz will be pure luck.
Hence the artificial limitation i set up in the boot.scr...

Regards,

3

Thank you, Robert.
So I misunderstood the meaning of mpurate. I thought is just means cpu
frequency, but actually it means core rate, right?

So I change it to mpurate 950, which is supposed to corresponding to
800MHz. Run the script, cpuinfo now shows that BogoMIPS is 803.49.
Great!

It shows that Crystal/core/MPU is 26/950/332 MHz, and cpuinfo shows
803.49. Notice that core is great than Mpu
Compare to original angstrom(the one came with xm), it shows Crystal/
core/MPU is 26/332/1000 MHz, and cpuinfo shows 995. Notice that the
Mpu is great than core.

The two schemes seems quit different. But both got high bogomips.

Could you explain me a little about the relationship between cpu
freqency and Core and MPU.

4

OT: apologies as the thread title specifically refers to Ubuntu...

...but we have RISC OS running at 1GHz (albeit with caution as the
temp checking isn't implemented yet).
http://www.riscosopen.org/forum/forums/5/topics/466?page=2#posts-4611

For anyone curious, there's a little post- RISC OS London Show chat
here:
http://www.iconbar.com/articles/London_show_approaches/index1260.html#115734
and also on the comp.sys.acorn newsgroups

The blog post(s) that some are anticipating
http://groups.google.com/group/beagleboard/browse_thread/thread/62e92273db32beec/b7aa1f1c33622351#b7aa1f1c33622351
will follow at some point and will be announced on this list.

5

Oh you can change it to anything you want... but without the digital
voltage scaling patches anything above 800Mhz will be pure luck.
Hence the artificial limitation i set up in the boot.scr...

Are the patches available somewhere? Are they included in newer kernels?

Regards,

--
Robert Nelson
http://www.rcn-ee.com/

Thanks,
Rafael

6

They aren't released in any kernel yet.. just follow
http://vger.kernel.org/vger-lists.html#linux-omap as they might get
merged this cycle..

Regards,