1#!/bin/sh 2# SPDX-License-Identifier: GPL-2.0-only 3 4# XIP kernel .data segment compressor 5# 6# Created by: Nicolas Pitre, August 2017 7# Copyright: (C) 2017 Linaro Limited 8# 9 10# This script locates the start of the .data section in xipImage and 11# substitutes it with a compressed version. The needed offsets are obtained 12# from symbol addresses in vmlinux. It is expected that .data extends to 13# the end of xipImage. 14 15set -e 16 17VMLINUX="$1" 18XIPIMAGE="$2" 19 20DD="dd status=none" 21 22# Use "make V=1" to debug this script. 23case "$KBUILD_VERBOSE" in 24*1*) 25 set -x 26 ;; 27esac 28 29sym_val() { 30 # extract hex value for symbol in $1 31 local val=$($NM "$VMLINUX" 2>/dev/null | sed -n "/ $1\$/{s/ .*$//p;q}") 32 [ "$val" ] || { echo "can't find $1 in $VMLINUX" 1>&2; exit 1; } 33 # convert from hex to decimal 34 echo $((0x$val)) 35} 36 37__data_loc=$(sym_val __data_loc) 38_edata_loc=$(sym_val _edata_loc) 39base_offset=$(sym_val _xiprom) 40 41# convert to file based offsets 42data_start=$(($__data_loc - $base_offset)) 43data_end=$(($_edata_loc - $base_offset)) 44 45# Make sure data occupies the last part of the file. 46file_end=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" "$XIPIMAGE") 47if [ "$file_end" != "$data_end" ]; then 48 printf "end of xipImage doesn't match with _edata_loc (%#x vs %#x)\n" \ 49 $(($file_end + $base_offset)) $_edata_loc 1>&2 50 exit 1; 51fi 52 53# be ready to clean up 54trap 'rm -f "$XIPIMAGE.tmp"; exit 1' 1 2 3 55 56# substitute the data section by a compressed version 57$DD if="$XIPIMAGE" count=$data_start iflag=count_bytes of="$XIPIMAGE.tmp" 58$DD if="$XIPIMAGE" skip=$data_start iflag=skip_bytes | 59gzip -9 >> "$XIPIMAGE.tmp" 60 61# replace kernel binary 62mv -f "$XIPIMAGE.tmp" "$XIPIMAGE" 63