Lab2 - Cross Compilation for Beagle Board using ARM Toolchain

I am successfully able to install all packages.

[gawk, autoconf, automake, libtool, libncurses5-dev, bison, flex, patch, gettext, texinfo, curl, subversion]

(5) Getting Crosstool-ng

Get the 1.4.2 release of Crosstool-ng from

http://ymorin.is-a-geek.org/dokuwiki/projects/crosstool

Expand the archive right in the current directory, and enter the Crosstool-ng source directory.

$ sudo tar xvjf crosstool-ng-1.4.2.tar.bz2

Go to the directory crosstool-ng-1.4.2

$ cd crosstool-ng-1.4.2

(6) Installing Crosstool-ng

We can either install Crosstool-ng globally on the system, or keep it locally in its download directory. We'll choose the latter solution. As documented in docs/overview.txt, do:

./configure --local

make

make install

Following Snapshot shows result of “make” and “make install” command.

Then you can get Crosstool-ng help by running 

./ct-ng help

(7) Configure the toolchain to produce

A single installation of Crosstool-ng allows to produce as many tool chains as you want for different architectures, with different C libraries and different versions of the various components.

Crosstool-ng comes with a set of ready-made configuration files for various typical setups: Crosstool-ng calls them «samples». They can be listed by using ./ct-ng help.

We will use the arm-unknown-linux-uclibcgnueabi sample. It can be loaded by issuing:

./ct-ng arm-unknown-linux-uclibcgnueabi

[Execute it from directory /home/harshlavingia/felabs/sysdev/toolchain/crosstool-ng-1.4.2]

Then, to refine the configuration, let's run the menuconfig interface:

./ct-ng menuconfig

In Path and misc options:

Change the prefix directory to /usr/local/xtools/${CT_TARGET}

This is the place where the toolchain will be installed.

Change the number of parallel jobs to 2 times the number of CPU cores in your workstation. Building your toolchain will be faster.

In Toolchain options:

Set «Tuple's alias» to arm-linux. This way, we will be able to use the compiler as arm linux gcc instead of arm-unknown-linux-uclibcgnueabi-gcc which is much longer.

In the C compiler options:

Disable Java and Fortran. We won't need them, so let's reduce the toolchain compilation time by removing them.

In Debug facilities:

Enable gdb, strace and ltrace. Remove the other options. In gdb options, enable the “Cross gdb” and “Build a static gdbserver” options; the other options are not needed.

(8) Produce the toolchain

1. Create the directory /usr/local/xtools/ and change its owner to your user, so that Crosstool-ng can write to it.

1. If crosstool-ng complains about the LD_LIBRARY_PATH environment variable, unset it as follows: 

$ unset LD_LIBRARY_PATH

1. Build Cross-Compiler

$ ./ct-ng build

Then wait! [When I did it took more than 2 hours]

For Ubuntu 10.04 [Lucid Linux] version you will get build error. You can see detailed error in file /usr/local/xtools/arm-unknown-linux-uclibcgnueabi/build.log.

I resolve this error with the help of following link.

http://git.uclibc.org/uClibc/commit/?id=49e81cada73616864b9b31df0aeb6961c30f5a6e

You need to patch this as below. Edit the following file.

$ vi ./targets/src/uClibc-0.9.30.1/extra/scripts/unifdef.c

Complete file path:

/home/[username]/felabs/sysdev/toolchain/crosstool-ng-1.4.2/targets/src/uClibc-0.9.30.1/extra/scripts/unidef.c

There are three changes which are shown in different color and + sign for which line you must add and – sign for which line you must remove.

static void             error(const char *);

static int              findsym(const char *);

static void             flushline(bool);

-static Linetype         getline(void);

+static Linetype         get_line(void);

static Linetype         ifeval(const char **);

static void             ignoreoff(void);

static void             ignoreon(void);

@@ -517,7 +517,7 @@ process(void)

              for (;;) {

                            linenum++;

-                            lineval = getline();

+                            lineval = get_line();

                            trans_table[ifstate[depth]][lineval]();

                            debug("process %s -> %s depth %d",

                                linetype_name[lineval],

@@ -531,7 +531,7 @@ process(void)

  * help from skipcomment().

  */

static Linetype

-getline(void)

+get_line(void)

{

              const char *cp;

              int cursym;

@@ -889,9 +889,8 @@ skipcomment(const char *cp)

                                                        cp += 1;

                                          } else if (strchr(" \t", *cp) != NULL) {

                                                        cp += 1;

-                                          } else {

+                                          } else

                                                        return (cp);

-                                          }

                                          continue;

                            case CXX_COMMENT:

                                          if (strncmp(cp, "\n", 1) == 0) {

............

Again follow the previous steps (6) from directory

[/home/[username]/felabs/sysdev/toolchain/crosstool-ng-1.4.2] and you can successfully build ARM tool chain.

(9) Testing the toolchain

You can now test your toolchain by adding /usr/local/xtools/arm-unknown-linux-uclibcgnueabi/bin/ to your PATH environment variable.

Content of directory [usr/local/xtools/arm-unknown-linux-uclibcgnueabi/bin] is shown as below.

Compile the simple hello.c program in your main lab directory with arm-linux-gcc. You can use the file command on your binary to make sure it has correctly been compiled for the ARM architecture.

$ arm-linux-gcc hello.c

$ file a.out

To write this code into first you need to compress this code and copy this code in SD card’s Root file system. Then extract it to get executable cross compiled binary. This is required to copy from one file system [Ubuntu linux] to SD card file system.

Now remove SD card from Laptop and plug into Beagle Board. [Check Lab3 document]

Then boot the kernel from SD card and you will get linux prompt. Type ls command to see the linux file system hierarchy which shown in following Snapshot.

Now you can execute your cross compiled binary file a.out of ARM platform on Beagle Board as below.

$ ./a.out

You can see the execution result in following Snapshot.

(10) Cleaning up

To save almost 2 GB of storage space, remove the targets/ subdirectory in the Crosstool-ng directory.

References

[1] CS530 class material website - http://octomize.com/~education/classes/embed_linux/beagle_board/slide/index_slide.html

[2] Software Archieve - http://free-electrons.com/labs/embedded_linux.tar.bz2

[3] Crosstool-ng [Download release 1.4.2] - http://ymorin.is-a-geek.org/dokuwiki/projects/crosstool

[4] Beagle Board information on Wikipedia - http://en.wikipedia.org/wiki/Beagle_Board

[5] Patch unidef.c file for Ubuntu 10.04 to successfully build tool chain 1.4.2

http://sourceware.org/ml/crossgcc/2009-10/msg00066.html

http://git.uclibc.org/uClibc/commit/?id=49e81cada73616864b9b31df0aeb6961c30f5a6e