#!/bin/bash

# vars:
# PROGRAM	the executable to run
# ARGUMENTS	the argument we're going to call PROGRAM with

DEVICE=/dev/cpu/microcode
PROGRAM=/usr/sbin/microcode_ctl
ARGUMENTS=-Qu
RETVAL=0

# Lets just be sure we have a device file...
if [ ! -e $DEVICE ] ; then
  echo "$0: microcode device $DEVICE doesn't exist"
  exit 1
elif [ ! -c $DEVICE ] ; then
  echo "$0: $DEVICE not a character device"
  exit 1
fi

microcode_ctl_start() {
  echo "Applying Intel IA32 Microcode update:  $PROGRAM"
  $PROGRAM $ARGUMENTS
  RETVAL=$?

  if [ $RETVAL -eq 3 ] ; then
    echo "$0: Cannot find source file \"/etc/microcode.dat\""
  fi

  # trap the most common case, errno 19 = no device
  if [ $RETVAL -eq 19 ] ; then
    if [ -e /proc/config.gz ] ; then
      gzip -dc /proc/config.gz | grep -q CONFIG_MICROCODE=
      GREPVAL=$?
    elif [ -e /boot/config ] ; then
      grep -q CONFIG_MICROCODE= /boot/config
      GREPVAL=$?
    elif [ -e /boot/System.map ] ; then
      grep -q microcode /boot/System.map
      GREPVAL=$?
    elif [ -e /usr/src/linux/include/linux/autoconf.h ] ; then
      grep -q ^#define.*MICROCODE /usr/src/linux/include/linux/autoconf.h
      GREPVAL=$?
    fi
    if [ $GREPVAL -ne 0 ] ; then
      echo "$0: This kernel doesn't appear to have microcode device support"
    fi
  fi
  exit $RETVAL
}

case "$1" in
'start')
  microcode_ctl_start
  ;;
*)
  echo "usage: $0 start"
esac