Editing Cross Compiling

[[Category:Linux]]
=Cross Compiling=

This page shows how to cross compile for CellBE/ppc64


== Gentoo ==

Server: Emerge distcc crossdev & env-update & source /etc/profile & crossdev -t powerpc64-unknown-linux-gnu

Client: http://www.gentoo.org/doc/en/cross-compiling-distcc.xml (Because it's much better written than anything I could do)

== Debian/Debian-based ==

===Know your host System===
To be improve the building time it is a good idea to know how many cores your processor has and have that number of concurrent jobs.

To know how many cores you have available use :

<pre>
grep -c '^processor' /proc/cpuinfo
</pre>

This will be used later on while building the toolchain ct-ng build.#number of cores and while compiling export CONCURRENCY_LEVEL=#number of cores.

Example for a quadcore system :

<pre>
ct-ng build.4
CONCURRENCY_LEVEL=4
</pre>


===Installing Cross Tool===

Install required packages :

<pre>
sudo apt-get install build-essential gawk bison flex automake libtool cvs lzma ncurses-dev texinfo patch g++ gcj mercurial git-core
</pre>

Add the enviromental variable to bash :

<pre>
sudo vi /etc/bash.bashrc

or

vi /home/user/.bashrc
</pre>

Add the following lines at the end of the file :


export PATH="${PATH}:/home/user/crosstool/bin/"

export PATH="${PATH}:/home/user/x-tools/powerpc64-unknown-linux-gnu/bin/"

export CONCURRENCY_LEVEL=#number


Create directories and compile crosstool :

<pre>
mkdir /home/user/crosstool
mkdir /home/user/kernel
mkdir -p /home/user/toolchain/powerpc
hg clone http://crosstool-ng.org/hg/crosstool-ng
cd crosstool-ng
./configure --prefix=/home/user/crosstool/
make && make install
</pre>

* /home/user/crosstool-ng/ -> '''crostool-ng sources'''
* /home/user/crosstool/ -> '''Crosstool install directory with binaries'''
* /home/user/toolchain/ -> '''Directory where the binary will be installed'''
* /home/user/toolchain/powerpc/ -> '''Crosstool files generated in this tutorial for powerpc'''
* /home/user/toolchain/x-tools/ -> '''generated toolchain'''
* /home/user/kernel -> '''Place were graf_chokolo's linux kernel tarball will be saved'''

===Patching crosstool===

NOTE : MAYBE THIS PATCHING STEP IS USELESS WITH LASTEST CROSSTOOL-NG REVISION

For some reason, the compiler removes the symbolic links for lib64.

The following patch corrects this behaviour allowing the toolchain to work properly without further modifications.

====Required Patch====

save the following file as """important.patch""" in home/user/crosstool/lib/ct-ng-1.10.0/scripts/build

<pre>
diff --git a/scripts/build/internals.sh b/scripts/build/internals.sh
--- a/scripts/build/internals.sh
+++ b/scripts/build/internals.sh
@@ -157,8 +157,6 @@
     # the standard lib/ dirs, so we can get rid of the symlinks
     for d in                            \
         "${CT_PREFIX_DIR}"              \
-        "${CT_SYSROOT_DIR}"             \
-        "${CT_SYSROOT_DIR}/usr"         \
         "${CT_PREFIX_DIR}/${CT_TARGET}" \
     ; do
         CT_DoExecLog ALL rm -f "${d}/lib32"
</pre>

Go to that directory and apply the patch :

<pre>
cd /home/user/crosstool/lib/ct-ng-yourcrosstoolversion/scripts/build
patch < important.patch
</pre>

===Creating a cross compiler toolchain for ppc64===

Download graf_chokolo's kernel :

<pre>
cd /home/user/kernel
git clone git://git.gitbrew.org/ps3/ps3linux/linux-2.6.git
tar -zcvf linux-2.6.tar.gz linux-2.6/
</pre>

Copy the sample configuration file and modify it :

<pre>
cp /home/user/crosstool/lib/ct-ng-yourcrosstoolversion/samples/powerpc64-unknown-linux-gnu/* /home/user/toolchain/powerpc/
cd /home/user/toolchain/powerpc/
mv crosstool.config .config
cd /home/user/toolchain/powerpc/
ct-ng menuconfig
</pre>

I've added graf_chokolos kernel :

*Operating System -> Linux Kernel version -> custom tarball
*Operating System -> Path to custom tarball -> /home/user/kernel/linux-2.6.tar.gz

'''or'''
----

Start from scratch and configure the toolchain the way you want :

<pre>
cd /home/user/toolchain/powerppc/
ct-ng menuconfig
</pre>

Compile ppc64 toolchain :

<pre>
unset LD_LIBRARY_PATH LIBRARY_PATH CPATH
export LD_LIBRARY_PATH LIBRARY_PATH CPATH
ct-ng build.#number
</pre>

'''Wait for some time until it finishes compiling'''
----

===Testing if your toolchain works properly===
<pre>
export PATH="${PATH}:/home/user/x-tools/powerpc64-unknown-linux-gnu/bin/"
powerpc64-unknown-linux-gnuspe-gcc test.c -o test
</pre>

More info: http://www.ibm.com/developerworks/linux/tutorials/l-embedded-distro/section3.html

===Cross compiling openssl===

Download openssl sources
<pre>
wget http://www.openssl.org/source/openssl-0.9.8g.tar.gz
</pre>

unpack the sources :

<pre>
tar -zxvf openssl-0.9.8g.tar.gz
</pre>

Go to openssl source path :

<pre>
cd openssl-0.9.8g/
</pre>

Change the following lines in the Makefile :

<pre>
INSTALLTOP= /home/user/x-tools/powerpc64-unknown-linux-gnu/powerpc64-unknown-linux-gnu/sysroot/usr
OPENSSLDIR= /home/user/x-tools/powerpc64-unknown-linux-gnu/powerpc64-unknown-linux-gnu/sysroot/usr
CC= powerpc64-unknown-linux-gnu-gcc
AR= powerpc64-unknown-linux-gnu-ar $(ARFLAGS) r
RANLIB= powerpc64-unknown-linux-gnu-ranlib
</pre>

Finally :

<pre>
make
</pre>

===Cross compiling graf_chokolo's tools===

Make sure you have a working toolchain and openssl installed

Comment the current compiler and add your cross compiler in our case "powerpc64-unknown-linux-gnu-gcc" :

<pre>
#CC=gcc
CC=powerpc64-unknown-linux-gnu-gcc
</pre>

Finally :

<pre>
make
</pre>

You can find graf_chokolo tools and scripts here :

http://git-hacks.com/linux-ps3

===Compiling graf_chokolo's kernel and making a deb package===

Go to the directory where you saved your kernel, untar it and go to the kernel source directory :

<pre>
cd /home/user/kernel
tar xfvz linux-2.6.tar.gz
cd linux-2.6
</pre>

It is a good measure to clean the source directory :

<pre>
make clean
make-kpkg clean
</pre>

Export set ARCH=powerpc
And set the right number of concurrent jobs to be done this is used to improve the building time :

<pre>
export ARCH=powerpc
export CONCURRENCY_LEVEL=4
</pre>


Use graf_chokolo config file :

<pre>
cp ps3_linux_config .config
make oldconfig
</pre>

You can customize your by using make menuconfig.

Now lets compile and package our kernel :

<pre>
make-kpkg --arch=powerpc --cross-compile=powerpc64-unknown-linux-gnu- --rootcmd=fakeroot --initrd --append-to-version=-graf kernel_image kernel_source kernel_headers
</pre>