Merge "Add kernel-rebuilding script for the emulator."

2 files changed, 182 insertions, 1 deletions

diff --git a/distrib/build-kernel.sh b/distrib/build-kernel.sh
new file mode 100755
index 0000000..769a9a6
--- /dev/null
+++ b/distrib/build-kernel.sh
@@ -0,0 +1,150 @@
+#!/bin/sh
+#
+# A small script used to rebuild the Android goldfish kernel image
+# See docs/KERNEL.TXT for usage instructions.
+#
+MACHINE=goldfish
+VARIANT=goldfish
+OUTPUT=/tmp/kernel-qemu
+CROSSPREFIX=arm-eabi-
+CONFIG=goldfish
+
+# Extract number of processors
+JOBS=`grep -c "processor" /proc/cpuinfo`
+JOBS=$(( $JOBS*2 ))
+
+ARCH=arm
+
+OPTION_HELP=no
+OPTION_ARMV7=no
+OPTION_OUT=
+OPTION_CROSS=
+OPTION_ARCH=
+OPTION_CONFIG=
+
+for opt do
+    optarg=$(expr "x$opt" : 'x[^=]*=\(.*\)')
+    case $opt in
+    --help|-h|-\?) OPTION_HELP=yes
+        ;;
+    --armv7)
+        OPTION_ARMV7=yes
+        ;;
+    --out=*)
+        OPTION_OUT=$optarg
+        ;;
+    --cross=*)
+        OPTION_CROSS=$optarg
+        ;;
+    --arch=*)
+        OPTION_ARCH=$optarg
+        ;;
+    --config=*)
+        OPTION_CONFIG=$optarg
+        ;;
+    -j*)
+        JOBS=$optarg
+        ;;
+    *)
+        echo "unknown option '$opt', use --help"
+        exit 1
+    esac
+done
+
+if [ $OPTION_HELP = "yes" ] ; then
+    echo "Rebuild the prebuilt kernel binary for Android's emulator."
+    echo ""
+    echo "options (defaults are within brackets):"
+    echo ""
+    echo "  --help                   print this message"
+    echo "  --arch=<arch>            change target architecture [$ARCH]"
+    echo "  --armv7                  build ARMv7 binaries (see note below)"
+    echo "  --out=<directory>        output directory [$OUTPUT]"
+    echo "  --cross=<prefix>         cross-toolchain prefix [$CROSSPREFIX]"
+    echo "  --config=<name>          kernel config name [$CONFIG]"
+    echo ""
+    echo "NOTE: --armv7 is equivalent to --config=goldfish_armv7. It is"
+    echo "      ignored if --config=<name> is used."
+    echo ""
+    exit 0
+fi
+
+if [ -n "$OPTION_ARCH" ]; then
+    ARCH="$OPTION_ARCH"
+fi
+
+if [ -n "$OPTION_CONFIG" ]; then
+    CONFIG="$OPTION_CONFIG"
+elif [ "$OPTION_ARMV7" = "yes" ]; then
+    CONFIG=goldfish_armv7
+fi
+
+# Check that we are in the kernel directory
+if [ ! -d arch/$ARCH/mach-$MACHINE ] ; then
+    echo "Cannot find arch/$ARCH/mach-$MACHINE. Please cd to the kernel source directory."
+    echo "Aborting."
+    #exit 1
+fi
+
+# Check output directory.
+if [ -n "$OPTION_OUT" ] ; then
+    if [ ! -d "$OPTION_OUT" ] ; then
+        echo "Output directory '$OPTION_OUT' does not exist ! Aborting."
+        exit 1
+    fi
+    OUTPUT=$OPTION_OUT
+else
+    mkdir -p $OUTPUT
+fi
+
+if [ -n "$OPTION_CROSS" ] ; then
+    CROSSPREFIX="$OPTION_CROSS"
+else
+    case $ARCH in
+        arm)
+            CROSSPREFIX=arm-eabi-
+            ZIMAGE=zImage
+            ;;
+        x86)
+            CROSSPREFIX=i686-android-linux-
+            ZIMAGE=bzImage
+            ;;
+        *)
+            echo "ERROR: Unsupported architecture!"
+            exit 1
+            ;;
+    esac
+fi
+
+export CROSS_COMPILE="$CROSSPREFIX" ARCH SUBARCH=$ARCH
+
+# Check that the cross-compiler is in our path
+#
+CROSS_COMPILER="${CROSS_COMPILE}gcc"
+CROSS_COMPILER_VERSION=$($CROSS_COMPILER --version 2>/dev/null)
+if [ $? != 0 ] ; then
+    echo "It looks like $CROSS_COMPILER is not in your path ! Aborting."
+    exit 1
+fi
+
+rm -f include/asm &&
+make ${CONFIG}_defconfig &&    # configure the kernel
+make -j$JOBS                   # build it
+
+if [ $? != 0 ] ; then
+    echo "Could not build the kernel. Aborting !"
+    exit 1
+fi
+
+OUTPUT_KERNEL=kernel-qemu
+OUTPUT_VMLINUX=vmlinux-qemu
+if [ "$OPTION_ARMV7" = "yes" ] ; then
+    OUTPUT_KERNEL=${OUTPUT_KERNEL}-armv7
+    OUTPUT_VMLINUX=${OUTPUT_VMLINUX}-armv7
+fi
+
+cp -f arch/$ARCH/boot/$ZIMAGE $OUTPUT/$OUTPUT_KERNEL
+cp -f vmlinux $OUTPUT/$OUTPUT_VMLINUX
+
+echo "Kernel $CONFIG prebuilt image copied to $OUTPUT successfully !"
+exit 0
diff --git a/docs/KERNEL.TXT b/docs/KERNEL.TXT
index e174fe5..35d1f1f 100644
--- a/docs/KERNEL.TXT
+++ b/docs/KERNEL.TXT
@@ -1,6 +1,37 @@
 HOW TO REBUILT THE ANDROID EMULATOR-SPECIFIC KERNEL:
 ====================================================
 
+I. Helper script:
+-----------------
+
+We now provide a helper script to rebuild the kernel,
+it is under distrib/rebuild-kernel.sh.
+
+You need the sources in android.git.kernel.org/kernel/common.git,
+in branch origin/archive/android-gldfish-2.6.29 (note the typo!)
+
+To rebuild the ARM kernel:
+
+  cd $KERNEL_SOURCES
+  /path/to/rebuild-kernel.sh --out=$ANDROID/prebuilt/android-arm/kernel
+
+To rebuild the x86 kernel:
+
+  cd $KERNEL_SOURCES
+  /path/to/rebuild-kernel.sh --arch=x86 --out=$ANDROID/prebuilt/android-x86/kernel
+
+Note that you will need to have your cross-toolchain in your path.
+If this is not the case, the script will complain and give you the
+expected name. Use --cross=<prefix> to specify a different toolchain.
+
+See rebuild-kernel.sh --help for more options and details.
+
+
+II. Rebuilding from scratch:
+----------------------------
+
+If you don't or can't use the script, here are manual instructions:
+
 You need to have the Android toolchain in your path
 (i.e. 'arm-eabi-gcc --version' must work)
 
@@ -8,7 +39,7 @@ then:
 
 git clone git://android.git.kernel.org/kernel/common.git kernel-common
 cd kernel-common
-git checkout origin/android-goldfish-2.6.29
+git checkout origin/archive/android-gldfish-2.6.29
 
 export CROSS_COMPILE=arm-eabi-
 export ARCH=arm