Fixed prebuilt path and toolchain names

1) Use "prebuilts" instead of "prebuilt" to legalize BUILD_TOP
2) Update CROSSTOOLCHAIN and CROSSPREFIX for all arch
3) Add -fno-pic because some toolchain (eg. x86 and mips)
   in prebuilts/gcc are NDK-compatible (ie. enforces -fpic, etc)

Verified to build working kernel-goldfish for all arch

Change-Id: I93ac8f0beeaae14aa4575629fd8eaf4af73ef7ce

2 files changed, 21 insertions, 25 deletions

diff --git a/distrib/build-kernel.sh b/distrib/build-kernel.sh
index 4b50353..67488ac 100755
--- a/distrib/build-kernel.sh
+++ b/distrib/build-kernel.sh
@@ -6,7 +6,7 @@
 MACHINE=goldfish
 VARIANT=goldfish
 OUTPUT=/tmp/kernel-qemu
-CROSSPREFIX=arm-eabi-
+CROSSPREFIX=arm-linux-androideabi-
 CONFIG=goldfish
 
 # Determine the host architecture, and which default prebuilt tag we need.
@@ -127,15 +127,15 @@ if [ -n "$OPTION_CROSS" ] ; then
 else
     case $ARCH in
         arm)
-            CROSSTOOLCHAIN=arm-eabi-4.4.3
-            CROSSPREFIX=arm-eabi-
+            CROSSTOOLCHAIN=arm-linux-androideabi-4.6
+            CROSSPREFIX=arm-linux-androideabi-
             ;;
         x86)
             CROSSTOOLCHAIN=i686-linux-android-4.6
             CROSSPREFIX=i686-linux-android-
             ;;
         mips)
-            CROSSTOOLCHAIN=mipsel-linux-android-4.4.3
+            CROSSTOOLCHAIN=mipsel-linux-android-4.6
             CROSSPREFIX=mipsel-linux-android-
             ;;
         *)
@@ -166,17 +166,13 @@ if [ $? != 0 ] ; then
         # Assume this script is under external/qemu/distrib/ in the
         # Android source tree.
         BUILD_TOP=$(dirname $0)/../../..
-        if [ ! -d "$BUILD_TOP/prebuilt" ]; then
+        if [ ! -d "$BUILD_TOP/prebuilts" ]; then
             BUILD_TOP=
         else
             BUILD_TOP=$(cd $BUILD_TOP && pwd)
         fi
     fi
-    if [ "$ARCH" = "mips" ]; then
-        CROSSPREFIX=$BUILD_TOP/prebuilts/gcc/$HOST_TAG/$ARCH/$CROSSTOOLCHAIN/bin/$CROSSPREFIX
-    else
-        CROSSPREFIX=$BUILD_TOP/prebuilt/$HOST_TAG/toolchain/$CROSSTOOLCHAIN/bin/$CROSSPREFIX
-    fi
+    CROSSPREFIX=$BUILD_TOP/prebuilts/gcc/$HOST_TAG/$ARCH/$CROSSTOOLCHAIN/bin/$CROSSPREFIX
     if [ "$BUILD_TOP" -a -f ${CROSSPREFIX}gcc ]; then
         echo "Auto-config: --cross=$CROSSPREFIX"
     else
@@ -195,15 +191,11 @@ fi
 
 
 # Special magic redirection with our magic toolbox script
-# This is needed to add extra compiler flags for x86
+# This is needed to add extra compiler flags to compiler.
+# See kernel-toolchain/android-kernel-toolchain-* for details
 #
-# We could use that for ARM, but don't need to at the moment.
-#
-if [ "$ARCH" = "x86" ]; then
-    export REAL_CROSS_COMPILE="$CROSS_COMPILE"
-    export ARCH
-    CROSS_COMPILE=$(dirname "$0")/kernel-toolchain/android-kernel-toolchain-
-fi
+export REAL_CROSS_COMPILE="$CROSS_COMPILE"
+CROSS_COMPILE=$(dirname "$0")/kernel-toolchain/android-kernel-toolchain-
 
 # Do the build
 #
diff --git a/distrib/kernel-toolchain/toolbox.sh b/distrib/kernel-toolchain/toolbox.sh
index b9947e2..89b49bb 100755
--- a/distrib/kernel-toolchain/toolbox.sh
+++ b/distrib/kernel-toolchain/toolbox.sh
@@ -1,10 +1,10 @@
 #!/bin/sh
 #
-# This is a wrapper around our x86 toolchain that allows us to add a few
+# This is a wrapper around our toolchain that allows us to add a few
 # compiler flags.
-# The issue is that our x86 toolchain is NDK-compatible, and hence enforces
-# -mfpmath=sse and -fpic by default. When building the kernel, we need to
-# disable this.
+# The issue is that our toolchain are NDK-compatible, and hence enforces
+# -fpic (and also -mfpmath=sse for x86) by default.  When building the
+# kernel, we need to disable this.
 #
 # Also support ccache compilation if USE_CCACHE is defined as "1"
 #
@@ -43,9 +43,13 @@ PROGSUFFIX=${PROGNAME##$PROGPREFIX}
 
 EXTRA_FLAGS=
 
-# Special case #1: For x86, disable SSE FPU arithmetic, and PIC code
-if [ "$ARCH" = "x86" -a "$PROGSUFFIX" = gcc ]; then
-    EXTRA_FLAGS=$EXTRA_FLAGS" -mfpmath=387 -fno-pic"
+if [ "$PROGSUFFIX" = gcc ]; then
+    # Special case #1: For all, disable PIC code
+    EXTRA_FLAGS=$EXTRA_FLAGS" -fno-pic"
+    if [ "$ARCH" = "x86" ]; then
+        # Special case #2: For x86, disable SSE FPU arithmetic too
+        EXTRA_FLAGS=$EXTRA_FLAGS" -mfpmath=387"
+    fi
 fi
 
 # Invoke real cross-compiler toolchain program now