linux/arch/powerpc/boot/wrapper

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#!/bin/sh
# Copyright (C) 2006 Paul Mackerras, IBM Corporation <paulus@samba.org>
# This program may be used under the terms of version 2 of the GNU
# General Public License.
# This script takes a kernel binary and optionally an initrd image
# and/or a device-tree blob, and creates a bootable zImage for a
# given platform.
# Options:
# -o zImage specify output file
# -p platform specify platform (links in $platform.o)
# -i initrd specify initrd file
# -d devtree specify device-tree blob
# -s tree.dts specify device-tree source file (needs dtc installed)
# -c cache $kernel.strip.gz (use if present & newer, else make)
# -C prefix specify command prefix for cross-building tools
# (strip, objcopy, ld)
# -D dir specify directory containing data files used by script
# (default ./arch/powerpc/boot)
# -W dir specify working directory for temporary files (default .)
# -z use gzip (legacy)
# -Z zsuffix compression to use (gz, xz or none)
# Stop execution if any command fails
set -e
# Allow for verbose output
if [ "$V" = 1 ]; then
set -x
fi
# defaults
kernel=
ofile=zImage
platform=of
initrd=
dtb=
dts=
cacheit=
binary=
compression=.gz
pie=
format=
# cross-compilation prefix
CROSS=
# mkimage wrapper script
MKIMAGE=$srctree/scripts/mkuboot.sh
# directory for object and other files used by this script
object=arch/powerpc/boot
objbin=$object
dtc=scripts/dtc/dtc
# directory for working files
tmpdir=.
usage() {
echo 'Usage: wrapper [-o output] [-p platform] [-i initrd]' >&2
echo ' [-d devtree] [-s tree.dts] [-c] [-C cross-prefix]' >&2
echo ' [-D datadir] [-W workingdir] [-Z (gz|xz|none)]' >&2
echo ' [--no-compression] [vmlinux]' >&2
exit 1
}
run_cmd() {
if [ "$V" = 1 ]; then
$* 2>&1
else
local msg
set +e
msg=$($* 2>&1)
if [ $? -ne "0" ]; then
echo $msg
exit 1
fi
set -e
fi
}
while [ "$#" -gt 0 ]; do
case "$1" in
-o)
shift
[ "$#" -gt 0 ] || usage
ofile="$1"
;;
-p)
shift
[ "$#" -gt 0 ] || usage
platform="$1"
;;
-i)
shift
[ "$#" -gt 0 ] || usage
initrd="$1"
;;
-d)
shift
[ "$#" -gt 0 ] || usage
dtb="$1"
;;
-s)
shift
[ "$#" -gt 0 ] || usage
dts="$1"
;;
-c)
cacheit=y
;;
-C)
shift
[ "$#" -gt 0 ] || usage
CROSS="$1"
;;
-D)
shift
[ "$#" -gt 0 ] || usage
object="$1"
objbin="$1"
;;
-W)
shift
[ "$#" -gt 0 ] || usage
tmpdir="$1"
;;
-z)
compression=.gz
;;
-Z)
shift
[ "$#" -gt 0 ] || usage
[ "$1" != "gz" -o "$1" != "xz" -o "$1" != "none" ] || usage
compression=".$1"
if [ $compression = ".none" ]; then
compression=
fi
;;
--no-gzip)
# a "feature" of the the wrapper script is that it can be used outside
# the kernel tree. So keeping this around for backwards compatibility.
compression=
;;
-?)
usage
;;
*)
[ -z "$kernel" ] || usage
kernel="$1"
;;
esac
shift
done
if [ -n "$dts" ]; then
if [ ! -r "$dts" -a -r "$object/dts/$dts" ]; then
dts="$object/dts/$dts"
fi
if [ -z "$dtb" ]; then
dtb="$platform.dtb"
fi
$dtc -O dtb -o "$dtb" -b 0 "$dts"
fi
if [ -z "$kernel" ]; then
kernel=vmlinux
fi
LANG=C elfformat="`${CROSS}objdump -p "$kernel" | grep 'file format' | awk '{print $4}'`"
case "$elfformat" in
elf64-powerpcle) format=elf64lppc ;;
elf64-powerpc) format=elf32ppc ;;
elf32-powerpc) format=elf32ppc ;;
esac
platformo=$object/"$platform".o
lds=$object/zImage.lds
ext=strip
objflags=-S
tmp=$tmpdir/zImage.$$.o
ksection=.kernel:vmlinux.strip
isection=.kernel:initrd
link_address='0x400000'
make_space=y
case "$platform" in
of)
platformo="$object/of.o $object/epapr.o"
make_space=n
;;
pseries)
platformo="$object/pseries-head.o $object/of.o $object/epapr.o"
link_address='0x4000000'
if [ "$format" != "elf32ppc" ]; then
link_address=
pie=-pie
fi
make_space=n
;;
maple)
platformo="$object/of.o $object/epapr.o"
link_address='0x400000'
make_space=n
;;
pmac|chrp)
platformo="$object/of.o $object/epapr.o"
make_space=n
;;
coff)
platformo="$object/crt0.o $object/of.o $object/epapr.o"
lds=$object/zImage.coff.lds
link_address='0x500000'
make_space=n
pie=
;;
miboot|uboot*)
# miboot and U-boot want just the bare bits, not an ELF binary
ext=bin
objflags="-O binary"
tmp="$ofile"
ksection=image
isection=initrd
;;
cuboot*)
binary=y
compression=
[POWERPC] bootwrapper: Build multiple cuImages Currently, the kernel uses CONFIG_DEVICE_TREE to wrap a kernel image with a fdt blob which means for any given configuration only one dts file can be selected and so support for only one board can be built This moves the selection of the default .dts file out of the kernel config and into the bootwrapper makefile. The makefile chooses which images to build based on the kernel config and the dts source file name is taken directly from the image name. For example "cuImage.ebony" will use "ebony.dts" as the device tree source file. In addition, this patch allows a specific image to be requested from the command line by adding "cuImage.%" and "treeImage.%" targets to the list of valid built targets in arch/powerpc/Makefile. This allows the default dts selection to be overridden. Another advantage to this change is it allows a single defconfig to be supplied for all boards using the same chip family and only differing in the device tree. Important note: This patch adds two new zImage targets; zImage.dtb.% and zImage.dtb.initrd.% for zImages with embedded dtb files. Currently there are 5 platforms which require this: ps3, ep405, mpc885ads, ep88xc, adder875-redboot and ep8248e. This patch *changes the zImage filenames* for those platforms. ie. 'zImage.ps3' is now 'zImage.dtb.ps3'. This new zImage.dtb targets were added so that the .dts file could be part of the dependancies list for building them. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-02-07 02:18:34 +08:00
case "$platform" in
*-mpc866ads|*-mpc885ads|*-adder875*|*-ep88xc)
[POWERPC] bootwrapper: Build multiple cuImages Currently, the kernel uses CONFIG_DEVICE_TREE to wrap a kernel image with a fdt blob which means for any given configuration only one dts file can be selected and so support for only one board can be built This moves the selection of the default .dts file out of the kernel config and into the bootwrapper makefile. The makefile chooses which images to build based on the kernel config and the dts source file name is taken directly from the image name. For example "cuImage.ebony" will use "ebony.dts" as the device tree source file. In addition, this patch allows a specific image to be requested from the command line by adding "cuImage.%" and "treeImage.%" targets to the list of valid built targets in arch/powerpc/Makefile. This allows the default dts selection to be overridden. Another advantage to this change is it allows a single defconfig to be supplied for all boards using the same chip family and only differing in the device tree. Important note: This patch adds two new zImage targets; zImage.dtb.% and zImage.dtb.initrd.% for zImages with embedded dtb files. Currently there are 5 platforms which require this: ps3, ep405, mpc885ads, ep88xc, adder875-redboot and ep8248e. This patch *changes the zImage filenames* for those platforms. ie. 'zImage.ps3' is now 'zImage.dtb.ps3'. This new zImage.dtb targets were added so that the .dts file could be part of the dependancies list for building them. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-02-07 02:18:34 +08:00
platformo=$object/cuboot-8xx.o
;;
*5200*|*-motionpro)
platformo=$object/cuboot-52xx.o
;;
*-pq2fads|*-ep8248e|*-mpc8272*|*-storcenter)
platformo=$object/cuboot-pq2.o
;;
*-mpc824*)
platformo=$object/cuboot-824x.o
;;
*-mpc83*|*-asp834x*)
[POWERPC] bootwrapper: Build multiple cuImages Currently, the kernel uses CONFIG_DEVICE_TREE to wrap a kernel image with a fdt blob which means for any given configuration only one dts file can be selected and so support for only one board can be built This moves the selection of the default .dts file out of the kernel config and into the bootwrapper makefile. The makefile chooses which images to build based on the kernel config and the dts source file name is taken directly from the image name. For example "cuImage.ebony" will use "ebony.dts" as the device tree source file. In addition, this patch allows a specific image to be requested from the command line by adding "cuImage.%" and "treeImage.%" targets to the list of valid built targets in arch/powerpc/Makefile. This allows the default dts selection to be overridden. Another advantage to this change is it allows a single defconfig to be supplied for all boards using the same chip family and only differing in the device tree. Important note: This patch adds two new zImage targets; zImage.dtb.% and zImage.dtb.initrd.% for zImages with embedded dtb files. Currently there are 5 platforms which require this: ps3, ep405, mpc885ads, ep88xc, adder875-redboot and ep8248e. This patch *changes the zImage filenames* for those platforms. ie. 'zImage.ps3' is now 'zImage.dtb.ps3'. This new zImage.dtb targets were added so that the .dts file could be part of the dependancies list for building them. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-02-07 02:18:34 +08:00
platformo=$object/cuboot-83xx.o
;;
*-tqm8541|*-mpc8560*|*-tqm8560|*-tqm8555|*-ksi8560*)
[POWERPC] bootwrapper: Build multiple cuImages Currently, the kernel uses CONFIG_DEVICE_TREE to wrap a kernel image with a fdt blob which means for any given configuration only one dts file can be selected and so support for only one board can be built This moves the selection of the default .dts file out of the kernel config and into the bootwrapper makefile. The makefile chooses which images to build based on the kernel config and the dts source file name is taken directly from the image name. For example "cuImage.ebony" will use "ebony.dts" as the device tree source file. In addition, this patch allows a specific image to be requested from the command line by adding "cuImage.%" and "treeImage.%" targets to the list of valid built targets in arch/powerpc/Makefile. This allows the default dts selection to be overridden. Another advantage to this change is it allows a single defconfig to be supplied for all boards using the same chip family and only differing in the device tree. Important note: This patch adds two new zImage targets; zImage.dtb.% and zImage.dtb.initrd.% for zImages with embedded dtb files. Currently there are 5 platforms which require this: ps3, ep405, mpc885ads, ep88xc, adder875-redboot and ep8248e. This patch *changes the zImage filenames* for those platforms. ie. 'zImage.ps3' is now 'zImage.dtb.ps3'. This new zImage.dtb targets were added so that the .dts file could be part of the dependancies list for building them. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-02-07 02:18:34 +08:00
platformo=$object/cuboot-85xx-cpm2.o
;;
*-mpc85*|*-tqm85*|*-sbc85*)
[POWERPC] bootwrapper: Build multiple cuImages Currently, the kernel uses CONFIG_DEVICE_TREE to wrap a kernel image with a fdt blob which means for any given configuration only one dts file can be selected and so support for only one board can be built This moves the selection of the default .dts file out of the kernel config and into the bootwrapper makefile. The makefile chooses which images to build based on the kernel config and the dts source file name is taken directly from the image name. For example "cuImage.ebony" will use "ebony.dts" as the device tree source file. In addition, this patch allows a specific image to be requested from the command line by adding "cuImage.%" and "treeImage.%" targets to the list of valid built targets in arch/powerpc/Makefile. This allows the default dts selection to be overridden. Another advantage to this change is it allows a single defconfig to be supplied for all boards using the same chip family and only differing in the device tree. Important note: This patch adds two new zImage targets; zImage.dtb.% and zImage.dtb.initrd.% for zImages with embedded dtb files. Currently there are 5 platforms which require this: ps3, ep405, mpc885ads, ep88xc, adder875-redboot and ep8248e. This patch *changes the zImage filenames* for those platforms. ie. 'zImage.ps3' is now 'zImage.dtb.ps3'. This new zImage.dtb targets were added so that the .dts file could be part of the dependancies list for building them. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-02-07 02:18:34 +08:00
platformo=$object/cuboot-85xx.o
;;
*-amigaone)
link_address='0x800000'
;;
[POWERPC] bootwrapper: Build multiple cuImages Currently, the kernel uses CONFIG_DEVICE_TREE to wrap a kernel image with a fdt blob which means for any given configuration only one dts file can be selected and so support for only one board can be built This moves the selection of the default .dts file out of the kernel config and into the bootwrapper makefile. The makefile chooses which images to build based on the kernel config and the dts source file name is taken directly from the image name. For example "cuImage.ebony" will use "ebony.dts" as the device tree source file. In addition, this patch allows a specific image to be requested from the command line by adding "cuImage.%" and "treeImage.%" targets to the list of valid built targets in arch/powerpc/Makefile. This allows the default dts selection to be overridden. Another advantage to this change is it allows a single defconfig to be supplied for all boards using the same chip family and only differing in the device tree. Important note: This patch adds two new zImage targets; zImage.dtb.% and zImage.dtb.initrd.% for zImages with embedded dtb files. Currently there are 5 platforms which require this: ps3, ep405, mpc885ads, ep88xc, adder875-redboot and ep8248e. This patch *changes the zImage filenames* for those platforms. ie. 'zImage.ps3' is now 'zImage.dtb.ps3'. This new zImage.dtb targets were added so that the .dts file could be part of the dependancies list for building them. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-02-07 02:18:34 +08:00
esac
;;
ps3)
platformo="$object/ps3-head.o $object/ps3-hvcall.o $object/ps3.o"
lds=$object/zImage.ps3.lds
compression=
ext=bin
objflags="-O binary --set-section-flags=.bss=contents,alloc,load,data"
ksection=.kernel:vmlinux.bin
isection=.kernel:initrd
link_address=''
make_space=n
pie=
;;
ep88xc|ep405|ep8248e)
platformo="$object/fixed-head.o $object/$platform.o"
binary=y
;;
adder875-redboot)
platformo="$object/fixed-head.o $object/redboot-8xx.o"
binary=y
;;
simpleboot-virtex405-*)
platformo="$object/virtex405-head.o $object/simpleboot.o $object/virtex.o"
binary=y
;;
simpleboot-virtex440-*)
platformo="$object/fixed-head.o $object/simpleboot.o $object/virtex.o"
binary=y
;;
simpleboot-*)
platformo="$object/fixed-head.o $object/simpleboot.o"
binary=y
;;
asp834x-redboot)
platformo="$object/fixed-head.o $object/redboot-83xx.o"
binary=y
;;
xpedite52*)
link_address='0x1400000'
platformo=$object/cuboot-85xx.o
;;
gamecube|wii)
link_address='0x600000'
platformo="$object/$platform-head.o $object/$platform.o"
;;
treeboot-currituck)
link_address='0x1000000'
;;
treeboot-akebono)
link_address='0x1000000'
;;
treeboot-iss4xx-mpic)
platformo="$object/treeboot-iss4xx.o"
;;
epapr)
platformo="$object/pseries-head.o $object/epapr.o $object/epapr-wrapper.o"
link_address='0x20000000'
pie=-pie
;;
mvme5100)
platformo="$object/fixed-head.o $object/mvme5100.o"
binary=y
;;
mvme7100)
platformo="$object/motload-head.o $object/mvme7100.o"
link_address='0x4000000'
binary=y
;;
esac
vmz="$tmpdir/`basename \"$kernel\"`.$ext"
# Calculate the vmlinux.strip size
${CROSS}objcopy $objflags "$kernel" "$vmz.$$"
strip_size=$(stat -c %s $vmz.$$)
if [ -z "$cacheit" -o ! -f "$vmz$compression" -o "$vmz$compression" -ot "$kernel" ]; then
# recompress the image if we need to
case $compression in
.xz)
xz --check=crc32 -f -6 "$vmz.$$"
;;
.gz)
gzip -n -f -9 "$vmz.$$"
;;
*)
# drop the compression suffix so the stripped vmlinux is used
compression=
;;
esac
if [ -n "$cacheit" ]; then
mv -f "$vmz.$$$compression" "$vmz$compression"
else
vmz="$vmz.$$"
fi
else
rm -f $vmz.$$
fi
vmz="$vmz$compression"
if [ "$make_space" = "y" ]; then
# Round the size to next higher MB limit
round_size=$(((strip_size + 0xfffff) & 0xfff00000))
round_size=0x$(printf "%x" $round_size)
link_addr=$(printf "%d" $link_address)
if [ $link_addr -lt $strip_size ]; then
echo "INFO: Uncompressed kernel (size 0x$(printf "%x\n" $strip_size))" \
"overlaps the address of the wrapper($link_address)"
echo "INFO: Fixing the link_address of wrapper to ($round_size)"
link_address=$round_size
fi
fi
# Extract kernel version information, some platforms want to include
# it in the image header
version=`${CROSS}strings "$kernel" | grep '^Linux version [-0-9.]' | \
cut -d' ' -f3`
if [ -n "$version" ]; then
uboot_version="-n Linux-$version"
fi
# physical offset of kernel image
membase=`${CROSS}objdump -p "$kernel" | grep -m 1 LOAD | awk '{print $7}'`
case "$platform" in
uboot)
rm -f "$ofile"
${MKIMAGE} -A ppc -O linux -T kernel -C gzip -a $membase -e $membase \
$uboot_version -d "$vmz" "$ofile"
if [ -z "$cacheit" ]; then
rm -f "$vmz"
fi
exit 0
;;
uboot-obs600)
rm -f "$ofile"
# obs600 wants a multi image with an initrd, so we need to put a fake
# one in even when building a "normal" image.
if [ -n "$initrd" ]; then
real_rd="$initrd"
else
real_rd=`mktemp`
echo "\0" >>"$real_rd"
fi
${MKIMAGE} -A ppc -O linux -T multi -C gzip -a $membase -e $membase \
$uboot_version -d "$vmz":"$real_rd":"$dtb" "$ofile"
if [ -z "$initrd" ]; then
rm -f "$real_rd"
fi
if [ -z "$cacheit" ]; then
rm -f "$vmz"
fi
exit 0
;;
esac
addsec() {
${CROSS}objcopy $4 $1 \
--add-section=$3="$2" \
--set-section-flags=$3=contents,alloc,load,readonly,data
}
addsec $tmp "$vmz" $ksection $object/empty.o
if [ -z "$cacheit" ]; then
rm -f "$vmz"
fi
if [ -n "$initrd" ]; then
addsec $tmp "$initrd" $isection
fi
if [ -n "$dtb" ]; then
addsec $tmp "$dtb" .kernel:dtb
if [ -n "$dts" ]; then
rm $dtb
fi
fi
if [ "$platform" != "miboot" ]; then
if [ -n "$link_address" ] ; then
text_start="-Ttext $link_address"
fi
#link everything
${CROSS}ld -m $format -T $lds $text_start $pie -o "$ofile" \
[POWERPC] zImage: Cleanup and improve zImage entry point This patch re-organises the way the zImage wrapper code is entered, to allow more flexibility on platforms with unusual entry conditions. After this patch, a platform .o file has two options: 1) It can define a _zimage_start, in which case the platform code gets control from the very beginning of execution. In this case the platform code is responsible for relocating the zImage if necessary, clearing the BSS, performing any platform specific initialization, and finally calling start() to load and enter the kernel. 2) It can define platform_init(). In this case the generic crt0.S handles initial entry, and calls platform_init() before calling start(). The signature of platform_init() is changed, however, to take up to 5 parameters (in r3..r7) as they come from the platform's initial loader, instead of a fixed set of parameters based on OF's usage. When using the generic crt0.S, the platform .o can optionally supply a custom stack to use, using the BSS_STACK() macro. If this is not supplied, the crt0.S will assume that the loader has supplied a usable stack. In either case, the platform code communicates information to the generic code (specifically, a PROM pointer for OF systems, and/or an initrd image address supplied by the bootloader) via a global structure "loader_info". In addition the wrapper script is rearranged to ensure that the platform .o is always linked first. This means that platforms where the zImage entry point is at a fixed address or offset, rather than being encoded in the binary header can be supported using option (1). Signed-off-by: David Gibson <dwg@au1.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-03-05 11:24:52 +08:00
$platformo $tmp $object/wrapper.a
rm $tmp
fi
# Some platforms need the zImage's entry point and base address
base=0x`${CROSS}nm "$ofile" | grep ' _start$' | cut -d' ' -f1`
entry=`${CROSS}objdump -f "$ofile" | grep '^start address ' | cut -d' ' -f3`
if [ -n "$binary" ]; then
mv "$ofile" "$ofile".elf
${CROSS}objcopy -O binary "$ofile".elf "$ofile"
fi
# post-processing needed for some platforms
case "$platform" in
pseries|chrp|maple)
$objbin/addnote "$ofile"
;;
coff)
[POWERPC] zImage: Cleanup and improve zImage entry point This patch re-organises the way the zImage wrapper code is entered, to allow more flexibility on platforms with unusual entry conditions. After this patch, a platform .o file has two options: 1) It can define a _zimage_start, in which case the platform code gets control from the very beginning of execution. In this case the platform code is responsible for relocating the zImage if necessary, clearing the BSS, performing any platform specific initialization, and finally calling start() to load and enter the kernel. 2) It can define platform_init(). In this case the generic crt0.S handles initial entry, and calls platform_init() before calling start(). The signature of platform_init() is changed, however, to take up to 5 parameters (in r3..r7) as they come from the platform's initial loader, instead of a fixed set of parameters based on OF's usage. When using the generic crt0.S, the platform .o can optionally supply a custom stack to use, using the BSS_STACK() macro. If this is not supplied, the crt0.S will assume that the loader has supplied a usable stack. In either case, the platform code communicates information to the generic code (specifically, a PROM pointer for OF systems, and/or an initrd image address supplied by the bootloader) via a global structure "loader_info". In addition the wrapper script is rearranged to ensure that the platform .o is always linked first. This means that platforms where the zImage entry point is at a fixed address or offset, rather than being encoded in the binary header can be supported using option (1). Signed-off-by: David Gibson <dwg@au1.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-03-05 11:24:52 +08:00
${CROSS}objcopy -O aixcoff-rs6000 --set-start "$entry" "$ofile"
$objbin/hack-coff "$ofile"
;;
cuboot*)
gzip -n -f -9 "$ofile"
${MKIMAGE} -A ppc -O linux -T kernel -C gzip -a "$base" -e "$entry" \
$uboot_version -d "$ofile".gz "$ofile"
;;
treeboot*)
mv "$ofile" "$ofile.elf"
$objbin/mktree "$ofile.elf" "$ofile" "$base" "$entry"
if [ -z "$cacheit" ]; then
rm -f "$ofile.elf"
fi
exit 0
;;
ps3)
# The ps3's loader supports loading a gzipped binary image from flash
# rom to ram addr zero. The loader then enters the system reset
# vector at addr 0x100. A bootwrapper overlay is used to arrange for
# a binary image of the kernel to be at addr zero, and yet have a
# suitable bootwrapper entry at 0x100. To construct the final rom
# image 512 bytes from offset 0x100 is copied to the bootwrapper
# place holder at symbol __system_reset_kernel. The 512 bytes of the
# bootwrapper entry code at symbol __system_reset_overlay is then
# copied to offset 0x100. At runtime the bootwrapper program copies
# the data at __system_reset_kernel back to addr 0x100.
system_reset_overlay=0x`${CROSS}nm "$ofile" \
| grep ' __system_reset_overlay$' \
| cut -d' ' -f1`
system_reset_overlay=`printf "%d" $system_reset_overlay`
system_reset_kernel=0x`${CROSS}nm "$ofile" \
| grep ' __system_reset_kernel$' \
| cut -d' ' -f1`
system_reset_kernel=`printf "%d" $system_reset_kernel`
overlay_dest="256"
overlay_size="512"
${CROSS}objcopy -O binary "$ofile" "$ofile.bin"
run_cmd dd if="$ofile.bin" of="$ofile.bin" conv=notrunc \
skip=$overlay_dest seek=$system_reset_kernel \
count=$overlay_size bs=1
run_cmd dd if="$ofile.bin" of="$ofile.bin" conv=notrunc \
skip=$system_reset_overlay seek=$overlay_dest \
count=$overlay_size bs=1
odir="$(dirname "$ofile.bin")"
rm -f "$odir/otheros.bld"
gzip -n --force -9 --stdout "$ofile.bin" > "$odir/otheros.bld"
;;
esac