vcgencmd - Raspberry Pi GPU Firmware CLI

# Alpine Linux
apk add raspberrypi-utils-vcgencmd

vcgencmd version            # Show firmware version
vcgencmd measure_temp       # Show GPU temperature
vcgencmd get_throttled      # Check for under-voltage or overheating issues (see breakdown below)
vcgencmd measure_clock arm  # Show ARM (CPU) clock frequency in Hz
vcgencmd measure_volts core # Show core voltage

vcgencmd get_mem arm     # Show memory allocated to ARM (CPU) in MB
vcgencmd get_mem gpu     # Show memory allocated to GPU in MB
vcgencmd display_power 1 # Turn display power ON
vcgencmd display_power 0 # Turn display power OFF

vcgencmd codec_enabled H264  # Check if H264 hardware codec is enabled
vcgencmd codec_enabled MJPEG # Check if MJPEG hardware codec is enabled

# 解析 get_throttled 位
v=$(( $(vcgencmd get_throttled | cut -d= -f2) ))
for b in 0:under-voltage 1:freq-capped 2:throttled 3:soft-temp-limit \
  16:under-voltage-occurred 17:freq-capped-occurred 18:throttled-occurred 19:soft-temp-limit-occurred; do
  if (( v >> ${b%%:*} & 1 )); then echo "${b#*:}"; fi
done

volt=0.8563V (core)
volt=1.1000V (sdram_c)
volt=1.1000V (sdram_i)
volt=1.1000V (sdram_p)

arm_64bit=1
arm_freq=1500
core_freq=500
total_mem=1024