#!/bin/sh

# Install a Debian kernel on a Buffalo Linkstation Pro/Live
# - intended to be automatically triggered by /etc/kernel-img.conf
# That file should contain at least:
# do_symlinks = Yes
# do_initrd = Yes
# link_in_boot = Yes
# postinst_hook = /usr/local/bin/install-linkstation-kernel
#
# Copyright 2008 Tim Small tim@seoss.co.uk
# Released under the terms of the GNU General Public License Version 2
#



#KERNEL=vmlinuz-2.6.26-rc6-orion5x
#INITRD=initrd.img-2.6.26-rc6-orion5x
KERNEL=/boot/vmlinuz
INITRD=/boot/initrd.img
KUIMAGE=/boot/uImage.buffalo
IUIMAGE=/boot/initrd.buffalo

UBOOT_MKIMAGE=/usr/bin/mkimage
DEVIO=/usr/bin/devio

cleanup()
{
	rm -f $KERNEL_SHIM $SHIMMED_KERNEL $NEWKUIMAGE $NEWIUIMAGE
}
	

if [ ! -x $DEVIO ]
then
	apt-get install devio
fi

if [ ! -x $UBOOT_MKIMAGE ]
then
	apt-get install uboot-mkimage
fi


KERNEL_SHIM=`mktemp -t kernelshim.XXXXXXXXXX` || exit 1
SHIMMED_KERNEL=`mktemp -t shimmedkernel.XXXXXXXXXX`
if [ $? -ne 0 ]; then
	cleanup
	exit 1
fi


NEWKUIMAGE=`mktemp -p /boot newkuimage.XXXXXXXXXX`
if [ $? -ne 0 ]; then
	cleanup
	exit 1
fi


NEWIUIMAGE=`mktemp -p /boot newiuimage.XXXXXXXXXX`
if [ $? -ne 0 ]; then
	cleanup
	exit 1
fi


# This devio command writes a machine-code shim to the start of the kernel
# image, to change the machine type number passed to the kernel by uboot

# First sanity check what we're running on.

# First case - a Linkstation which is already running a Debian kernel
# Second case - original Buffalo kernel with incorrect machine type

if ( ! grep -E -q '^Hardware.*Buffalo.*Pro'  /proc/cpuinfo) &&
   ( ! (grep -E -q '^Hardware.*MV-88fxx81' /proc/cpuinfo || grep -q 'panic=5 BOOTVER=' /proc/cmdline))
then
	echo "Not a linkstation?  Refusing to continue..."
	cleanup
	exit 1
fi

if [ ! -L $KERNEL ]
then
	echo "$0: Kernel symlink $KERNEL doesn't exist! Exiting"
	cleanup
	exit 1
fi

if [ ! -L $INITRD ]
then
	echo "$0: Kernel symlink $KERNEL doesn't exist! Exiting"
	cleanup
	exit 1
fi

# For kuropro use a different machine ID - 
#$DEVIO 'wl 0xe3a01c05,4' 'wl 0xe38110e5,4' > $KERNEL_SHIM
# Linkstation version -
$DEVIO 'wl 0xe3a01c06,4' 'wl 0xe3811031,4' > $KERNEL_SHIM
cat $KERNEL_SHIM $KERNEL > $SHIMMED_KERNEL
$UBOOT_MKIMAGE -A arm -O linux -T kernel -C none -a 0x00008000 -e 0x00008000 -n `readlink $KERNEL` -d $SHIMMED_KERNEL $NEWKUIMAGE
if [ $? -ne 0 ]; then
	cleanup
	exit 1
fi
$UBOOT_MKIMAGE -A arm -O linux -T ramdisk -C none -a 0x00000000 -e 0x00000000 -n `readlink $INITRD` -d $INITRD $NEWIUIMAGE
if [ $? -ne 0 ]; then
	cleanup
	exit 1
fi

if mkimage -l /boot/initrd.buffalo | grep -q -E '^Image Name:.*initrd$' && mkimage -l /boot/uImage.buffalo | grep -q -E '^Image Name:.*-arm1' 
then
	BACKUP_SUFFIX='_original'
else
	BACKUP_SUFFIX='.old'
fi

mv -f $KUIMAGE ${KUIMAGE}${BACKUP_SUFFIX} && mv -f $NEWKUIMAGE $KUIMAGE
mv -f $IUIMAGE $IUIMAGE${BACKUP_SUFFIX} && mv -f $NEWIUIMAGE $IUIMAGE

cleanup