Raspberry Pi Userland (VCGENCMD)

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   Warning

In above mentioned guide installation is more detailed

The Raspberry Pi is an ARM device (BCM2835, ARMv6).

This document contains notes about getting Funtoo Linux up-and-running on the Raspberry Pi. Most information is already available on other documents, so this document mostly explains how to get the information needed to perform the installation.

Please read Funtoo Linux Installation on ARM for general information about installing Funtoo Linux on ARM architecture.

Please read Raspberry Pi for general information about installing Funtoo Linux on Raspberry Pi Board (armv6j).

Installation

Raspberry Pi Userland

Get Raspberry Pi userspace tools and libraries (VCGENCMD):

root # cd /tmp/
root # git clone --depth 1 git://github.com/raspberrypi/firmware/
root # cp -r firmware/hardfp/opt/vc /opt/

Configure PATH and libs:

root # echo 'export PATH=/opt/vc/bin:/opt/vc/sbin:$PATH' >> /etc/profile
root # echo -e '# /etc/env.d/00vcgencmd\n# Do not edit this file\n\nLDPATH="/opt/vc/lib"' > /etc/env.d/00vcgencmd
root # source /etc/profile
root # env-update
root # ldconfig


Commands

Amount of memory dedicated to the operating system and video

root # vcgencmd get_mem arm && vcgencmd get_mem gpu

Frequency (clock)

root # for src in arm core h264 isp v3d uart pwm emmc pixel vec hdmi dpi ; do echo -e "$src:\t$(vcgencmd measure_clock $src)" ; done

Volts

root # for id in core sdram_c sdram_i sdram_p ; do  echo -e "$id:\t$(vcgencmd measure_volts $id)" ;  done

Version

Show firmware version:

root # vcgencmd version

Temperature

Try measure temperature:

root # vcgencmd measure_temp
temp=48.7'C

Codecs

Shows whether the specified codec is enabled, the codec can be one of H264, MPG2, WVC1, MPG4, MJPG, WMV9. Please note that it was implemented in a Pi with licenses MPG2 e VC1 activated.

root # for codec in H264 MPG2 WVC1 MPG4 MJPG WMV9 ; do echo -e "$codec:\t$(vcgencmd codec_enabled $codec)" ; done

Performance analysis

This analysis require "stress" ebuild:

root # emerge app-benchmarks/stress

Measure the temperature and cause a 'stress' to measure heat dissipation:

root # vcgencmd measure_temp && stress  --cpu 1 -t 300 &&  vcgencmd measure_temp

You may notice that "stress" the processor increases the temperature, but nowhere near 80 ° C. I always compile a lot of things in parallel so distributed with x86_64 hosts or other raspberry's cluster.