CPU freq

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1

I noticed that the board is slow and the CPU freq is 300000 - Beaglebone Black A5B

Linux arm 3.8.13-bone32 #1 SMP Fri Dec 13 20:05:25 UTC 2013 armv7l armv7l armv7l GNU/Linux
root@arm:~# cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq
300000

I know that powering from USB the board will slow down to 300000 MHz but the board is powered from +5 V with a 5Amps power supply

I even boot only from power supply and attach the usb cable after boot sequence (monitoring LED)
Any idea how to switch to high freq ? I also have problems with the USB host - I presume that it is also related to wrong detection of primary power supply

2

Change the cpu governor to “performance” and you will see difference

3

I know

But I want to be done automatically at start-up.

Because of poor power management I also have some USB problems

I will post later.

Now I look at differences between Angstrom and Ubuntu.

Angstrom does a far better job with power management and USB devices but does not have some devices files for USB G3 modem and RS 232/USB adapters I must use.

4

I know

But I want to be done automatically at start-up.

/etc/default/cpufrequtils
https://wiki.debian.org/HowTo/CpuFrequencyScaling

Because of poor power management I also have some USB problems

I will post later.

Uh, so why don't you post the details now?

Now I look at differences between Angstrom and Ubuntu.

Angstrom does a far better job with power management and USB devices but
does not have some devices files for USB G3 modem and RS 232/USB adapters I
must use.

Regards,

5

I just wanted to better document the problems.
Some of them:
If I put USB modem Huawei 3772 direct into the USB connector it flashes and then the power is cut off
If I put a USB hub between the same, but if I put another device into the hub everything is OK and I manage to work with the modem

I will put a list and screen captures wit dmesg later

6

I just wanted to better document the problems.
Some of them:
If I put USB modem Huawei 3772 direct into the USB connector it flashes and then the power is cut off

Is the device powered by USB or the 5volt barrel connector? (what rating)

If I put a USB hub between the same, but if I put another device into the hub everything is OK and I manage to work with the modem

If that fixes it, then your USB modem is crap, taking way too much
current on startup..

Regards,

7

+5 V barrel by a lab power supply 5V/5Amps
the current is 500 mA and the modem works perfect in Angstrom

8

Well they share the "same" patchset (minus 1-2 distro related
patches).. So you have the Angstrom .config (1) and mine (2)

1: https://github.com/beagleboard/kernel/blob/3.8/configs/beaglebone
2: https://github.com/RobertCNelson/linux-dev/blob/am33x-v3.8/patches/defconfig

Care to bisect/debug?

Regards,