#!/bin/bash
# This shell script used auto download bootloader source code and do cross compile

source ../scripts/setup_env.sh

PRJ_PATH=`pwd`

KERNEL_SRC=linux-imx

patch_file=${PRJ_PATH}/patch/linux-imx-${BSP_VER}.patch
arch=arm
defconf=${BOARD}_defconfig
drvpath=${PRJ_PATH}/../images/drivers

set -u
set -e

function do_fetch()
{
    if [ -d $KERNEL_SRC ] ; then
        pr_warn "$KERNEL_SRC fetched already."
        return 0;
    fi

    do_fetch_json $JSON_CONF KERNEL_SRC $KERNEL_SRC
}

function do_patch()
{
    cd ${KERNEL_SRC}

    if [ ! -s arch/arm/configs/$defconf -a  -s $patch_file ] ; then
        pr_warn "Patch for ${KERNEL_SRC} source code"
        patch -p1 < $patch_file
    fi

    pr_warn "Modify cross compiler in Makefile: $CROSS_TOOL"
    sed -i -e "s|^CROSS_COMPILE.*|CROSS_COMPILE?=${CROSS_TOOL}|g" Makefile

    cd ${PRJ_PATH}
}

function do_build()
{
    pr_warn "Build for ${KERNEL_SRC} source code"

    cd ${KERNEL_SRC}

    make $defconf
    make -j ${JOBS}
    make modules_install INSTALL_MOD_PATH=$drvpath INSTALL_MOD_STRIP=1

    cd ${PRJ_PATH}
}


function do_install()
{
    pr_warn "Install linux kernel image"

    cd ${KERNEL_SRC}

    do_install_json $JSON_CONF "INSTALL"

    cd ${PRJ_PATH}
}

function do_clean()
{
    pr_warn "Clean ${KERNEL_SRC} source code"

    cd ${KERNEL_SRC}

    make distclean

    cd ${PRJ_PATH}
}

function gen_patch()
{
    pr_warn "Clean ${KERNEL_SRC} source code"

    cd ${KERNEL_SRC}
    if [ -f .config ] ; then
        make savedefconfig
        mv defconfig arch/arm/configs/$defconf
    fi
    make distclean
    cd -

    mv ${KERNEL_SRC} ${KERNEL_SRC}-${BSP_VER}

    pr_warn "Fetch orignal source code"
    do_fetch

    pr_warn "Generate ${KERNEL_SRC} patch file"

    set +e
    diff -Nuar --no-dereference -x logo_linux_clut224.ppm ${KERNEL_SRC} ${KERNEL_SRC}-${BSP_VER} > $patch_file

    rm -rf ${KERNEL_SRC}
    mv ${KERNEL_SRC}-${BSP_VER} ${KERNEL_SRC}
}

function do_usage()
{
    echo ""
    echo "Usage:"
    echo "  $0 [-b] [-p] [-c] [-h]"
    echo "     -b: download and build $PRJ_NAME"
    echo "     -p: generate $PRJ_NAME patch file"
    echo "     -c: clean the source code"
    echo "     -h: show this help message"
    echo ""
    exit;
}

while getopts "bpch" OPTNAME
do
    case "${OPTNAME}" in
        "b")
            break;
            ;;

        "p")
            gen_patch
            exit;
            ;;

        "c")
            do_clean
            exit;
            ;;

        "h")
            do_usage
            exit;
            ;;

        "*")
            do_usage
            exit;
            ;;
    esac
done

#default do build action

do_fetch
do_patch
do_build
do_install

exit;