Add initial build script

build.sh

@@ -0,0 +1,134 @@
+#!/bin/bash
+
+set -e
+
+kernel_source_dir=$PWD/linux
+kernel_source_url='https://github.com/chrultrabook/linux'
+kernel_config_dir=$PWD/config
+build_dir=$PWD/build
+
+# each variant has a different config, branch, arch, etc
+variants=('stoney' 'avs' 'mt8173')
+
+function build_kernel {
+    variant=$1
+    case $variant in
+        stoney)
+            branch=master
+	    arch=x86_64
+	    ;;
+	avs)
+	    branch=avs
+	    arch=x86_64
+	    ;;
+	mt8173)
+	    branch=linux-mt8173
+	    arch=arm64
+	    ;;
+    esac
+
+    output_dir=${build_dir}/${variant}
+    module_dir=${output_dir}/modules
+    header_dir=${output_dir}/headers
+    case $arch in
+        arm*) dtbs_dir=${output_dir}/dtbs ;;
+    esac
+
+    echo "Building $variant kernel"
+
+    if [[ ! -d $kernel_source_dir ]]; then
+        git clone $kernel_source_url $kernel_source_dir
+    fi
+    cd $kernel_source_dir
+    git switch $branch
+
+    # make sure source is clean from any previous builds
+    make clean
+
+    case $arch in
+        arm64) cross="aarch64-linux-gnu-";;
+    esac
+
+    # install config for variant
+    cp ${kernel_config_dir}/${variant}.config .config
+    make CROSS_COMPILE=$cross ARCH=$arch olddefconfig
+
+    # build kernel and modules
+    make CROSS_COMPILE=$cross ARCH=$arch -j$(nproc)
+
+    # install build files to output dir
+    mkdir -p $output_dir
+    case $arch in
+        arm*) install_cmd="zinstall dtbs_install";;
+	*) install_cmd="install";;
+    esac
+    make modules_install $install_cmd \
+	    ARCH=$arch \
+            INSTALL_MOD_PATH=$module_dir \
+	    INSTALL_MOD_STRIP=1 \
+	    INSTALL_PATH=$output_dir \
+	    INSTALL_DTBS_PATH=$dtbs_dir
+    cp .config $output_dir/config
+    cp System.map $output_dir/System.map
+    cp include/config/kernel.release $output_dir/kernel.release
+
+    # install header files
+    # stolen from arch's linux PKGBUILD
+    mkdir -p $header_dir
+
+    # build files
+    install -Dt "$header_dir" -m644 .config Makefile Module.symvers System.map \
+        vmlinux
+    install -Dt "$header_dir/kernel" -m644 kernel/Makefile
+    install -Dt "$header_dir/arch/x86" -m644 arch/x86/Makefile
+    cp -t "$header_dir" -a scripts
+
+    # header files
+    cp -t "$header_dir" -a include
+    cp -t "$header_dir/arch/x86" -a arch/x86/include
+    install -Dt "$header_dir/arch/x86/kernel" -m644 arch/x86/kernel/asm-offsets.s
+    install -Dt "$header_dir/drivers/md" -m644 drivers/md/*.h
+    install -Dt "$header_dir/net/mac80211" -m644 net/mac80211/*.h
+    install -Dt "$header_dir/drivers/media/i2c" -m644 drivers/media/i2c/msp3400-driver.h
+    install -Dt "$header_dir/drivers/media/usb/dvb-usb" -m644 drivers/media/usb/dvb-usb/*.h
+    install -Dt "$header_dir/drivers/media/dvb-frontends" -m644 drivers/media/dvb-frontends/*.h
+    install -Dt "$header_dir/drivers/media/tuners" -m644 drivers/media/tuners/*.h
+    install -Dt "$header_dir/drivers/iio/common/hid-sensors" -m644 drivers/iio/common/hid-sensors/*.h
+
+    # kconfig files
+    find . -name 'Kconfig*' -exec install -Dm644 {} "$header_dir/{}" \;
+
+    # remove documentation
+    rm -r "$header_dir/Documentation"
+
+    # remove broken symlinks
+    find -L "$header_dir" -type l -delete
+
+    # remove loose objects
+    find "$header_dir" -type f -name '*.o' -delete
+
+    # strip build tools
+    while read -rd '' file; do
+        case "$(file -Sib "$file")" in
+            application/x-sharedlib\;*)      # Libraries (.so)
+                strip "$file" ;;
+            application/x-archive\;*)        # Libraries (.a)
+                strip "$file" ;;
+            application/x-executable\;*)     # Binaries
+                strip "$file" ;;
+            application/x-pie-executable\;*) # Relocatable binaries
+                strip "$file" ;;
+        esac
+    done < <(find "$header_dir" -type f -perm -u+x ! -name vmlinux -print0)
+    strip $header_dir/vmlinux
+}
+
+# if an argument is passed to the script, build that variant. otherwise build each variant
+if [[ -n $1 ]]; then
+    variant = $1
+    build_kernel $variant
+else
+    for variant in ${variants[@]}; do
+        build_kernel $variant
+    done
+fi