Filesystem OverView

General
Modify
- Using The Correct Console Device
Arago
Angstrom
- Build
Host and Target
Notes
- Creating a Root File System for Linux on OMAP35x
Build FAQ

General

Modify

Using The Correct Console Device

update the /etc/inittab file in the filesystem used for kernel

S:2345:respawn:/sbin/getty 115200 ttyS2
by,
S:2345:respawn:/sbin/getty 115200 ttyO2

Arago

Setting Up Build Environment and build

ubuntu install dependency

sudo apt-get install diffstat texi2html chrpath subversion python-psyco

Create the directory
Create a new directory for the build environment:
```
$ mkdir $HOME/oe
$ cd $HOME/oe
```

Clone Arago repositories

Now check out the following repositories:

$ git clone git://arago-project.org/git/arago.git
$ git clone git://arago-project.org/git/arago-oe-dev.git
$ git clone git://arago-project.org/git/arago-bitbake.git

The directory should now be populated with 3 subdirectories – arago, arago-oe-dev and arago-bitbake.

Copy setup/config files
Arago repository comes with samples of arago/setenv and arago/conf/local.conf files, which you can use as a starting point, by copying them into their actual names (without .sample extension) and modifying to suit your needs:
```
$ cp arago/setenv.sample arago/setenv
$ cp arago/conf/local.conf.sample arago/conf/local.conf
```
- File: arago/setenv Edit arago/setenv file and make sure environment variables are set properly. OEBASE should point to the directory you’ve created in the beginning:
```
export OEBASE=$HOME/oe
```
- File: arago/setenv Also, in order to use a separate "scratch" area outside of home directory, you may want to enable SCRATCH variable and point it appropriately:
```
export SCRATCH=/sim/scratch_AID
```
Set the environment variables
```
$ . arago/seten
```
Or,
```
$ source arago/setenv
```
Point to CSL toolchain
If not done before, set the PATH variable to point to the CodeSourcery toolchain (refer to Getting CodeSourcery Toolchain(The binary distribution for 2009q1-203 version) for obtaining one):
```
$ export PATH=/opt/arm-2009q1/bin:$PATH
```
Build a minimal base filesystem
Now it should be ready to start a build of the minimal filesystem image:
```
$ bitbake arago-base-image
```

Build a "demo" filesystem for OMAP3 EVM

$ MACHINE=omap3evm bitbake arago-console-image

Build different kernels for supported platforms

$ MACHINE=omap3evm bitbake virtual/kernel
$ MACHINE=beagleboard bitbake virtual/kernel
$ MACHINE=dm6446-evm bitbake virtual/kernel
$ MACHINE=dm355-evm bitbake virtual/kernel

High-level hierarchy of arago-deploy directory

Resulting images and packages will be placed under arago-deploy directory - images for the filesystem, kernel and bootloader; and ipk for binary IPK packages, respectively.

arago-deploy
|-- images
|   |-- arago
|   |-- dm355-evm
|   |-- dm6446-evm
|   `-- omap3evm
|-- ipk
|   |-- all
|   |-- arago
|   |-- armv5te
|   |-- armv7a
|   |-- dm355-evm
|   |-- dm6446-evm
|   |-- i686
|   |-- i686-armv5te-sdk
|   |-- i686-armv7a-sdk
|   `-- omap3evm
`-- sdk

Build individual package recipes
You can also look in oe/arago/recipes for individual package recipes that you can bitbake. For example:
```
bitbake curl
bitbake thhtpd
```

build a native compiler (on dm8168) using

MACHINE=c6a816x-evm ./arago-bitbake/bin/bitbake gcc-4.3.3(since codesourcery is using 4.3.3) or
MACHINE=c6a816x-evm ./arago-bitbake/bin/bitbake task-sdk-native

Crosscompiling Outside of Arago

se the sound API of the ALSA (Advanced Linux Sound Architecture) project and call it sndtest.c:

#include <stdio.h>
#include <alsa/asoundlib.h>

int main()
{
        printf("Using ALSA %s\n", snd_asoundlib_version());
        return 0;
}

We need to get the header files and libraries for ALSA on our host system in order to compile and link our sample application. Luckily, everything we need is provided by Arago in form of ipk packages. Some of the packages, like dynamic libraries, are installed to the Arago filesystem. But header files and static libraries are not installed and usually are part of the -dev packages.

Our sample application using ALSA API would require the following ipk packages:

alsa-dev_1.0.18-r0.1_armv5te.ipk
libasound2_1.0.18-r0.1_armv5te.ipk
alsa-lib-dev_1.0.18-r0.1_armv5te.ipk

alsa-dev provides all the header files. libasound2 provides the dynamic library (which is also installed on the Arago filesystem for run-time operation). And alsa-lib-dev provides the necessary support to link our application against the dynamic library.

But it is possible to extract package content without opkg using only standard Linux tools (ar and tar) and don't worry about the package database:

$ ar -p alsa-dev_1.0.18-r0.1_armv5te.ipk data.tar.gz | tar -zx
$ ar -p libasound2_1.0.18-r0.1_armv5te.ipk data.tar.gz | tar -zx
$ ar -p alsa-lib-dev_1.0.18-r0.1_armv5te.ipk data.tar.gz | tar -zx

Above commands would extract the actual content of data.tar.gz inside each of the ipk packages to the current directory, re-creating the directory hierarchy of the target. Specifically, header files will be placed under ./usr/include and libraries under ./usr/lib

The resulting command would look like:

$ arm-none-linux-gnueabi-gcc -o sndtest sndtest.c -I./usr/include/ -L./usr/lib/ -lasound

Creating recipes in Arago

Notes from https://www.ridgerun.com/developer/wiki/index.php/Creating_recipes_in_Arago

Brief review of Arago directory layout
After setting up your build environment, your directory structure should look like this:
```
workspace
|-arago
|-arago-bitbake
|-arago-oe-dev
|-arago-custom
|-arago-tmp
`-dowloads
```
- arago-custom: You should place your custom recipes here and also any overrides to recipes contained in 'arago' or 'arago-oe-dev' directories. Bitbake gives highest preference to the recipes in this directory, making it possible for you to override any functionality without having to touch directories under Arago control.
- arago-tmp:This is where the build system keeps its working files and also where it places the output of the build. There's a lot going on here, so let's look at the top layer of the directory structure under arago-tmp:
  - cache: This is where bitbake caches information it obtains from parsing all available .bb files. You will not need to look in this directory.
  - stamps: This directory contains zero length files that are used to track each phase of the build as it is completed. You will normally not need to look in this directory.
  - cross: This directory contains the cross development tools for generating code for TI procesors.
  - staging: Header files, libraries, and other items needed by the build system are stored in this directory.
  - rootfs: After an image recipe build, this directory will contain the complete root file system for the image. This directory is suitable for nfs mounting.
  - deploy: This directory contains the final output of the build process: a set of images and ipkg files.
  - work:This appropriately named directory is where the real work gets done. A subdirectory is created for each package that is built.There will typically be several subdirectories in each package working directory, let's look at the main ones:
  - <packagename-dir>:This is where the downloaded source code is expanded and patched. It will typically contain the source code for the package as well as any associated makefiles and documentation.
  - packages: This is where the build system places the files which will be packaged into ipkg files.The contents of each of these subdirectories is a root based tree of files exactly as they are to be installed in the target system.
  - tmp: This directory contains the scripts used to build the package and also the log files generated during the build process for the package. This is an extremely valuable debugging resource when you need to see exactly what the build system is doing.
  - image: There is normally no reason to look in this directory. It will contain the directory structure for the package installation, but without the actual files.
```
tmp
|-cache
|-stamps
|-cross
|-staging
|-work
|-rootfs
`-deploy
```
Recipe Contents
Besides descriptive information about the package, a recipe also includes:
- The recipe's version
- Dependent packages
- Source code location
- Patches if necessary
- Instruction of how to configure and build the package files
- Installation location on the target machine
Writting a recipe
- Basic Variables
  Recipes usually use names of the form: packagename_{versionnumber}.bb We are going to use as example, sample-recipe₁.0.0.bb, its code is presented below:
```
DESCRIPTION = "Sample program"
 PR = "r0"
 DEPENDS = ""

 SRC_URI = " \
 file://sample.c \
 "
 S = "${WORKDIR}"

 do_compile () {
 ${CC} ${CFLAGS} ${LDFLAGS} -o sample sample.c
 }

 do_install () {
 install -d ${D}${bindir}/
 install -m 0755 ${S}/sample ${D}${bindir}/
 }

 FILES_${PN} = "${bindir}/sample"
```
  Variable Description
  PN
  The package name. Determined from the recipe filename - everything up until the first underscore is considered to be the package name. For the sample-recipe₁.0.0.bb recipe the PN variable would be set to "sample-recipe".
  
  PV
  The package version. Determined from the recipe filename - everything between the first underscore and the final .bb is considered to be the package version. For the sample-recipe₁.0.0.bb recipe the PV variable would be set to "1.0.0".
  
  P
  The package name and versions separated by a hyphen. For the sample-recipe₁.0.0.bb recipe the P variable would be set to "sample-recipe-1.0.0".
  
  PR
  The package release. This should be explicitly set in the recipe, if not set it defaults to "r0".
  
  WORKDIR
  The working directory is where the source code is extracted, where files (other than patches) are copied, and where the logs and installation files are created. WORKDIR is initialized to PN-PV-PR, so for example recipe sample-recipe₁.0.0.bb, the value of WORKDIR would be set to "sample-recipe₁.0.0-r0" (assuming that the recipe set PR to "r0")
  
  S
  This is the unpacked source directory.
  Bitbake expects to find the extracted source for a package in a directory called packagename-version in the WORKDIR directory. This is the directory which it will change to before patching, compiling and installing the package.
  
  For example, let's assume we have a package recipe called sample-recipe₁.0.0.bb and we are extracting the source from the sample-1.0.0.tar.gz file. Bitbake expects the source to end up in a directory called sample-1.0.0 within the WORKDIR.
  
  If the source does not end up in this directory, then bitbake needs to be told this by explicitly setting S.
  
  D
  This is the destination directory. It specifies where your package should be installed. The packaging system takes the contents of this directory and packages it for installation on the target.
  The directory structure beneath D should reflect where the package files are to end up in the target system. For example, if a package file is intended to end up in /usr/bin on the target system, the recipe should install the files into ${D}/usr/bin.
  
  It is considered poor practice to directly specify /usr/bin. The build system provides a set of variables that you should use instead (see table in Appendix). So for the example above, the proper installation directory specification would be ${D}${bindir}
  
  DESCRIPTION
  Specifies the text that will be displayed by the package management system to describe what the package is.
  
  MANTAINER The name of the mantainer and usually an e-mail address
  
  LICENSE The package license name
  
  DEPENDS
  If there were dependencies on any other packages to build or run, we would list them here.
  
  SRC_URI
  Tell the build system where to find source code for the package
  
  FILES_${PN}
  Describes the list of files to be installed
  
  RDEPENDS
  A list of recommended packages to be installed
- Local sources and remote sources
  specified the name of the source file "sample.c" with a file:// prefix, this is the way you must do it, if the source code is located in the local file system.
```
  SRC_URI = " \
  file://sample.c \
"
```
  the case where the source code is fetched from a remote machine.
```
SRC_URI = " \
 http//www.mysite.com/downloads/sample-${PV}.tgz 
 "
```
  A second change is possible because the build system sets the S variable to ${WORKDIR}${P} by default. If the tarball is constructed in the standard fashion, we are able to delete the line in our recipe that used to explicity set S for the location of our source files.
- Applying patches
```
SRC_URI = " \
 http//www.mysite.com/downloads/sample-${PV}.tgz\
 file://examplepatch.patch;patch=1 \
 "
```
- Adding md5sum information
```
SRC_URI = "http//downloads.sourceforge.net/media_files.tar.gz;name=mediafiles"
 SRC_URI[mediafiles.md5sum] = "ffc705fc5581c584d88bd88a8b9caedf"
```

Possible command options

Bitbake normally acts on all metafiles defined in local.conf. It resolves all dependencies and builds, what is needed. To be able to do this, it first scans all directories given by the BBFILES entry in local.conf and build a hash out of that.

mrodriguez@optimus:~/devdirs/vaddio$ bitbake --help
.

Options:
 --version             show program's version number and exit
 -h, --help            show this help message and exit
  .
 .
 .
                       shell.
 -c CMD, --cmd=CMD     Specify task to execute. Note that this only executes
                       the specified task for the providee and the packages
                       it depends on, i.e. 'compile' does not implicitly call
                       stage for the dependencies (IOW: use only if you know
                       what you are doing). Depending on the base.bbclass a
                       listtasks tasks is defined and will show available
                       tasks

The following list gives an overview over the bitbake commands:

clean: cleans the package (tmp/work). Does not touch deploy dir (this has to be done manually).
fetch: fetches the package source from the source tree.
patch: eventually patches the sources with the patches provided in the package.
configure: configures the package. Knows several configure methods like autoconf/automake, qmake.
compile: compiles the package.
build: builds the package.
install: install the package.
package: packages the package.

In the sample-recipe code, there are specific instructions for the commands: compile and install. Whether is a Makefile, those might not be necessary.

do_compile () {
${CC} ${CFLAGS} ${LDFLAGS} -o sample sample.c
}

do_install () {
install -d ${D}${bindir}/
install -m 0755 ${S}/sample ${D}${bindir}/
}

Appendix

Variable name	Definition	Typical value
prefix	/usr	/usr
base_prefix	(empty)	(empty)
exec_prefix	${base_prefix}	(empty)
base_bindir	${base_prefix}/bin	/bin
base_sbindir	${base_prefix}/sbin	/sbin
base_libdir	${base_prefix}/lib	/lib
datadir	${prefix}/share	/usr/share
sysconfdir	/etc	/etc
localstatedir	/var	/var
infodir	${datadir}/info	/usr/share/info
mandir	${datadir}/man	/usr/share/man
docdir	${datadir}/doc	/usr/share/doc
servicedir	/srv	/srv
bindir	${exec_prefix}/bin	/usr/bin
sbindir	${exec_prefix}/sbin	/usr/sbin
libexecdir	${exec_prefix}/libexec	/usr/libexec
libdir	${exec_prefix}/lib	/usr/lib
includedir	${exec_prefix}/include	/usr/include

Angstrom

Build

python-numpy_1.4.1

Error

Miss the libblas and liblapack

diff --git a/recipes/python/python-numpy/00-numpy-1.4.1-no-atlas.patch b/recipes/python/python-numpy/00-numpy-1.4.1-no-atlas.patch
new file mode 100644
index 0000000..925aeb6
--- /dev/null
+++ b/recipes/python/python-numpy/00-numpy-1.4.1-no-atlas.patch
@@ -0,0 +1,28 @@
+When trying to locate libblas and liblapack, numpy will use the host
+versions of those libraries if available. This breaks compilation when
+linking.
+
+diff -Naur numpy-1.4.1/numpy/core/setup.py numpy-1.4.1/numpy/core/setup.py
+--- numpy-1.4.1/numpy/core/setup.py    2010-04-22 11:35:23.000000000 +0200
++++ numpy-1.4.1/numpy/core/setup.py    2011-11-16 17:11:22.000000000 +0100
+@@ -777,7 +777,7 @@
+ 
+     # Configure blasdot
+     blas_info = get_info('blas_opt',0)
+-    #blas_info = {}
++    blas_info = {}
+     def get_dotblas_sources(ext, build_dir):
+         if blas_info:
+             if ('NO_ATLAS_INFO',1) in blas_info.get('define_macros',[]):
+diff -Naur numpy-1.4.1/numpy/linalg/setup.py numpy-1.4.1/numpy/linalg/setup.py
+--- numpy-1.4.1/numpy/linalg/setup.py  2010-04-18 12:06:18.000000000 +0200
++++ numpy-1.4.1/numpy/linalg/setup.py  2011-11-16 17:11:35.000000000 +0100
+@@ -9,7 +9,7 @@
+     config.add_data_dir('tests')
+ 
+     # Configure lapack_lite
+-    lapack_info = get_info('lapack_opt',0) # and {}
++    lapack_info = get_info('lapack_opt',0) and {}
+     def get_lapack_lite_sources(ext, build_dir):
+         if not lapack_info:
+             print "### Warning:  Using unoptimized lapack ###"
diff --git a/recipes/python/python-numpy_1.4.1.bb b/recipes/python/python-numpy_1.4.1.bb
index f4941cf..fbe9d8d 100644
--- a/recipes/python/python-numpy_1.4.1.bb
+++ b/recipes/python/python-numpy_1.4.1.bb
@@ -2,9 +2,10 @@ DESCRIPTION = "A sophisticated Numeric Processing Package for Python"
 SECTION = "devel/python"
 PRIORITY = "optional"
 LICENSE = "PSF"
-PR = "ml0"
+PR = "ml1"

 SRC_URI = "${SOURCEFORGE_MIRROR}/numpy/numpy-${PV}.tar.gz \
+           file://00-numpy-1.4.1-no-atlas.patch \
           file://config.h \
           file://numpyconfig.h \
          "

Then the result are: python-numpy_1.4.1.bb

DESCRIPTION = "A sophisticated Numeric Processing Package for Python"
SECTION = "devel/python"
PRIORITY = "optional"
LICENSE = "PSF"
#PR = "ml0"
PR = "ml1"

SRC_URI = "${SOURCEFORGE_MIRROR}/numpy/numpy-${PV}.tar.gz \
            file://00-numpy-1.4.1-no-atlas.patch \
           file://config.h \
           file://numpyconfig.h \
          "

S = "${WORKDIR}/numpy-${PV}"

inherit distutils

# Make the build fail and replace *config.h with proper one
# This is a ugly, ugly hack - Koen
do_compile_prepend() {
         BUILD_SYS=${BUILD_SYS} HOST_SYS=${HOST_SYS} \
         ${STAGING_BINDIR_NATIVE}/python setup.py build ${DISTUTILS_BUILD_ARGS} || \
         true
         cp ${WORKDIR}/*config.h ${S}/build/$(ls ${S}/build | grep src)/numpy/core/include/numpy/
}

SRC_URI[md5sum] = "5c7b5349dc3161763f7f366ceb96516b"
SRC_URI[sha256sum] = "2e7bb84573e5123e07f3c919fd433bc09b78d606252b6b719e385c2a981d8e06"

00-numpy-1.4.1-no-atlas.patch

When trying to locate libblas and liblapack, numpy will use the host
versions of those libraries if available. This breaks compilation when
linking.

diff -Naur numpy-1.4.1/numpy/core/setup.py numpy-1.4.1/numpy/core/setup.py
--- numpy-1.4.1/numpy/core/setup.py     2010-04-22 11:35:23.000000000 +0200
+++ numpy-1.4.1/numpy/core/setup.py     2011-11-16 17:11:22.000000000 +0100
@@ -777,7 +777,7 @@

     # Configure blasdot
     blas_info = get_info('blas_opt',0)
-    #blas_info = {}
+    blas_info = {}
     def get_dotblas_sources(ext, build_dir):
         if blas_info:
             if ('NO_ATLAS_INFO',1) in blas_info.get('define_macros',[]):
diff -Naur numpy-1.4.1/numpy/linalg/setup.py numpy-1.4.1/numpy/linalg/setup.py
--- numpy-1.4.1/numpy/linalg/setup.py   2010-04-18 12:06:18.000000000 +0200
+++ numpy-1.4.1/numpy/linalg/setup.py   2011-11-16 17:11:35.000000000 +0100
@@ -9,7 +9,7 @@
     config.add_data_dir('tests')

     # Configure lapack_lite
-    lapack_info = get_info('lapack_opt',0) # and {}
+    lapack_info = get_info('lapack_opt',0) and {}
     def get_lapack_lite_sources(ext, build_dir):
         if not lapack_info:
             print "### Warning:  Using unoptimized lapack ###"

libnet_1.1.2.1.bb

Error

openembedded/recipes/libnet/libnet_1.1.2.1.bb md5sum error 

or

ERROR: Unable to unpack '/home/testbed/oe/sources/downloads/libnet_1.1.2.1.orig.tar.gz' to '/home/testbed/oe/build/tmp-angstrom_2010_x/work/armv7a-angstrom-linux-gnueabi/libnet-1.1.2.1-r4' (cmd: tar xz --no-same-owner -f /home/testbed/oe/sources/downloads/libnet_1.1.2.1.orig.tar.gz):
Execution of 'tar xz --no-same-owner -f
/home/testbed/oe/sources/downloads/libnet_1.1.2.1.orig.tar.gz' failed with exit code 2:

Do
- delete the broken tar downloads/libnet_1.1.2.1.orig.tar.gz
- download it from http://us.archive.ubuntu.com/ubuntu/pool/universe/libn/libnet/libnet_1.1.2.1.orig.tar.gz
- compute the md5sum and correct libnet_1.1.2.1.orig.tar.gz.md5

iproute2-2.6.38

Download from http://repository.timesys.com/buildsources/i/iproute2/iproute2-2.6.38/
debianutils_2.30.tar.gz

Download from http://www.openpandora.org/firmware/sources/
base-passwd_3.5.20.tar.gz

from http://ftp.acc.umu.se/mirror/cdimage/snapshot/Debian/pool/main/b/base-passwd/

Host and Target

After setting up opkg respository and pointing it to apache webserver with my vmware, now allows me easy install of python, dropbear, perl, etc cross-complied using code sourcery.

On Host:
Install Apache sudo apt-get install apache2
After you finish building packages on host, refresh the package index on the host: > bitbake package-index
add a symlink to the arago deploy/ipk directory to apache's home page /var/www/oe-repo

On EVM:
Determine your host IP address, and then add a src/gz line to /etc/opkg/opkg.conf
On the device, re-fetch the package list : opkg update
On the device, search for packages or install them
opkg list '*strace*'= =opkg install strace

Notes

Creating a Root File System for Linux on OMAP35x

http://processors.wiki.ti.com/index.php/Creating_a_Root_File_System_for_Linux_on_OMAP35x

create the directory
For simplicity, this note will assume the user’s directory is “user”. The home directory is then /home/user

All source code will be in the “src” directory, or /home/user/src

Code will be built in the “build” directory, or /home/user/build

The target root file system will be built in the “target” directory, or /home/user/target

To create these directories, go to /home/user and enter
```
[root@localhost user]# cd /home/user
[root@localhost user]# mkdir src
[root@localhost user]# mkdir build
[root@localhost user]# mkdir target
```

Configure the Linux Kernel to Support File Systems

The Linux kernel must be configured to support the file systems described in this note. To configure the kernel enter “make menuconfig” on the command line.

Device Node Creation

The v2.6.22.x releases default to enabling hotplug, sysfs, and tmpfs. To make sure hotplug is set, type in “make menuconfig” and from the “Main menu” use the down arrow key to scroll down to the “General setup” entry and press the Enter key to select it. Scroll down to “Configure standard kernel features (for small systems)” and press the Enter key. Scroll down to “Support for hot-pluggable devices” and make sure it is set. The Space Bar selects and de-selects options. A sample sub-menu is shown below:

┌──────── Configure standard kernel features (for small systems) ─────────┐
│  Arrow keys navigate the menu.  <Enter> selects submenus --->.          │
│  Highlighted letters are hotkeys.  Pressing <Y> includes, <N> excludes, │
│  <M> modularizes features.  Press <Esc><Esc> to exit, <?> for Help, </> │
│  for Search.  Legend: [*] built-in  [ ] excluded  <M> module  < >       │
│ ┌─────────────────────────────────────────────────────────────────────┐ │
│ │    --- Configure standard kernel features (for small systems)       │ │
│ │    [*]   Enable 16-bit UID system calls                             │ │
│ │    [ ]   Sysctl syscall support                                     │ │
│ │    [*]   Load all symbols for debugging/ksymoops                    │ │
│ │    [ ]     Include all symbols in kallsyms                          │ │
│ │    [*]     Do an extra kallsyms pass                                │ │
│ │    [*]   Support for hot-pluggable devices                          │ │
│ │    [*]   Enable support for printk                                  │ │
│ │    [*]   BUG() support                                              │ │
│ │    [*]   Enable ELF core dumps                                      │ │
│ └────v(+)─────────────────────────────────────────────────────────────┘ │
├─────────────────────────────────────────────────────────────────────────┤
│                    <Select>    < Exit >    < Help >                     │

To ensure sysfs and tmpfs are selected, start back at the “Main menu” and scroll down to the “File systems” option. Press Enter to select it and then scroll down to the “Pseudo filesystems” option and press Enter to select it. The file systems selected here should be: /proc, /proc/sys, sysfs, and “Virtual memory file system support.” That last one is also referred to as /tmpfs. A sample sub-menu is shown below.

┌────────────────────────── Pseudo filesystems ───────────────────────────┐
│  Arrow keys navigate the menu.  <Enter> selects submenus --->.          │
│  Highlighted letters are hotkeys.  Pressing <Y> includes, <N> excludes, │
│  <M> modularizes features.  Press <Esc><Esc> to exit, <?> for Help, </> │
│  for Search.  Legend: [*] built-in  [ ] excluded  <M> module  < >       │
│ ┌─────────────────────────────────────────────────────────────────────┐ │
│ │    [*] /proc file system support                                    │ │
│ │    [*]   Sysctl support (/proc/sys)                                 │ │
│ │    [*] sysfs file system support                                    │ │
│ │    [*] Virtual memory file system support (former shm fs)           │ │
│ │    [ ]   Tmpfs POSIX Access Control Lists                           │ │
│ │    < > Userspace-driven configuration filesystem (EXPERIMENTAL)     │ │
│ │                                                                     │ │
│ │                                                                     │ │
│ │                                                                     │ │
│ │                                                                     │ │
│ └─────────────────────────────────────────────────────────────────────┘ │
├─────────────────────────────────────────────────────────────────────────┤
│                    <Select>    < Exit >    < Help >                     │
└─────────────────────────────────────────────────────────────────────────┘

Configure the Linux Kernel for Root File System over NFS

From the “Main Menu” use the down arrow to scroll down to “File systems” and select it by pressing the Enter key. Under “File Systems” scroll down to “Network file systems” and select it. On this page make sure that “NFS file system support”, “Provide NFSv3 client support”, “Provide NFSv4 client support,” and “Root file system on NFS” are selected. A sample sub-menu is shown below.

┌───────────────────────── Network File Systems ──────────────────────────┐
 │  Arrow keys navigate the menu.  <Enter> selects submenus --->.          │
 │  Highlighted letters are hotkeys.  Pressing <Y> includes, <N> excludes, │
 │  <M> modularizes features.  Press <Esc><Esc> to exit, <?> for Help, </> │
 │  for Search.  Legend: [*] built-in  [ ] excluded  <M> module  < >       │
 │ ┌─────────────────────────────────────────────────────────────────────┐ │
 │ │    <*> NFS file system support                                      │ │
 │ │    [*]   Provide NFSv3 client support                               │ │
 │ │    [ ]     Provide client support for the NFSv3 ACL protocol extensi│ │
 │ │    [*]   Provide NFSv4 client support (EXPERIMENTAL)                │ │
 │ │    [ ]   Allow direct I/O on NFS files                              │ │
 │ │    < > NFS server support                                           │ │
 │ │    [*] Root file system on NFS                                      │ │
 │ │    [ ] Support for rpcbind versions 3 & 4 (EXPERIMENTAL)            │ │
 │ │    --- Secure RPC: Kerberos V mechanism (EXPERIMENTAL)              │ │
 │ │    < > Secure RPC: SPKM3 mechanism (EXPERIMENTAL)                   │ │
 │ └────v(+)─────────────────────────────────────────────────────────────┘ │
 ├─────────────────────────────────────────────────────────────────────────┤
 │                    <Select>    < Exit >    < Help >                     │
 └─────────────────────────────────────────────────────────────────────────┘

Configure the Linux Kernel for RAMDISK support

In this configuration the u-boot boot loader is used to download a binary image to RAM and pass parameters to the kernel telling it the root file system is on a ramdisk, where it is located, and its size. From the “Main menu” scroll down to “Device Drivers” and select it. Then scroll down to “Block devices” and select it. On this sub-menu make sure “RAM disk support” is selected. For the “Default RAM disk size” enter 16384. The RAM disk built in this note is 16M.

┌───────────────────────────── Block devices ─────────────────────────────┐
│  Arrow keys navigate the menu.  <Enter> selects submenus --->.          │
│  Highlighted letters are hotkeys.  Pressing <Y> includes, <N> excludes, │
│  <M> modularizes features.  Press <Esc><Esc> to exit, <?> for Help, </> │
│  for Search.  Legend: [*] built-in  [ ] excluded  <M> module  < >       │
│ ┌─────────────────────────────────────────────────────────────────────┐ │
│ │    <*> Loopback device support                                      │ │
│ │    < >   Cryptoloop Support                                         │ │
│ │    < > Network block device support                                 │ │
│ │    < > Low Performance USB Block driver                             │ │
│ │    <*> RAM disk support                                             │ │
│ │    (16)  Default number of RAM disks                                │ │
│ │    (16384) Default RAM disk size (kbytes)                           │ │
│ │    (1024) Default RAM disk block size (bytes)                       │ │
│ │    < > Packet writing on CD/DVD media                               │ │
│ │    < > ATA over Ethernet support                                    │ │
│ └─────────────────────────────────────────────────────────────────────┘ │
├─────────────────────────────────────────────────────────────────────────┤
│                    <Select>    < Exit >    < Help >                     │
└─────────────────────────────────────────────────────────────────────────┘

The step above configures the kernel for build in a ramdisk. Now go back to the “Main menu” and again select “General setup.” Scroll down and make sure “Initial RAM filesystem and RAM disk (initramfs/initrd) support” is selected. By default in the T.I. kernel it is.

┌───────────────────────────── General setup ─────────────────────────────┐
│  Arrow keys navigate the menu.  <Enter> selects submenus --->.          │
│  Highlighted letters are hotkeys.  Pressing <Y> includes, <N> excludes, │
│  <M> modularizes features.  Press <Esc><Esc> to exit, <?> for Help, </> │
│  for Search.  Legend: [*] built-in  [ ] excluded  <M> module  < >       │
│ ┌────^(-)─────────────────────────────────────────────────────────────┐ │
│ │    [ ] Auditing support                                             │ │
│ │    <*> Kernel .config support                                       │ │
│ │    [*] Enable access to .config through /proc/config.gz             │ │
│ │    (14) Kernel log buffer size (16 => 64KB, 17 => 128KB)            │ │
│ │    [*] Create deprecated sysfs files                                │ │
│ │    [ ] Kernel->user space relay support (formerly relayfs)          │ │
│ │    [*] Initial RAM filesystem and RAM disk (initramfs/initrd) suppor│ │
│ │    ()    Initramfs source file(s)                                   │ │
│ │    [*] Optimize for size (Look out for broken compilers!)           │ │
│ │    [*] Configure standard kernel features (for small systems)  ---> │ │
│ │        Choose SLAB allocator (SLAB)  --->                           │ │
│ └─────────────────────────────────────────────────────────────────────┘ │
├─────────────────────────────────────────────────────────────────────────┤
│                    <Select>    < Exit >    < Help >                     │
└──────────────────────────────────────────────────────── ────────────────┘

Configure the Linux Kernel for Memory Technology Devices (MTD)

To use any of the flash file systems, such as JFFS2 or CRAMFS, the MTD layer must be configured. MTD are typically flash devices used for storage. Configuring the individual drivers can be tricky. If a device is CFI compliant then all that is needed is to select the CFI options. In this example, CFI is selected, as is Intel/Sharp just in case the part it not CFI compliant. Starting at the “Main menu” scroll down to “Device Drivers” and select it. Scroll down to “Memory Technology Devices (MTD) support” and select it. There are numerous options that can/should be selected. The screen captures below are length

┌──────────────── Memory Technology Device (MTD) support ─────────────────┐
│  Arrow keys navigate the menu.  <Enter> selects submenus --->.          │
│  Highlighted letters are hotkeys.  Pressing <Y> includes, <N> excludes, │
│  <M> modularizes features.  Press <Esc><Esc> to exit, <?> for Help, </> │
│  for Search.  Legend: [*] built-in  [ ] excluded  <M> module  < >       │
│ ┌─────────────────────────────────────────────────────────────────────┐ │
│ │    --- Memory Technology Device (MTD) support                       │ │
│ │    [ ]   Debugging                                                  │ │
│ │    <*>   MTD concatenating support                                  │ │
│ │    [*]   MTD partitioning support                                   │ │
│ │    < >     RedBoot partition table parsing                          │ │
│ │    [*]     Command line partition table parsing                     │ │
│ │    < >     ARM Firmware Suite partition parsing                     │ │
│ │    ---   User Modules And Translation Layers                        │ │
│ │    <*>   Direct char device access to MTD devices                   │ │
│ │    ---   Common interface to block layer for MTD 'translation layers│ │
│ │    <*>   Caching block device access to MTD devices                 │ │
│ │    < >   FTL (Flash Translation Layer) support                      │ │
│ │    < >   NFTL (NAND Flash Translation Layer) support                │ │
│ │    < >   INFTL (Inverse NAND Flash Translation Layer) support       │ │
│ │    < >   Resident Flash Disk (Flash Translation Layer) support      │ │
│ │    < >   NAND SSFDC (SmartMedia) read only translation layer        │ │
│ │          RAM/ROM/Flash chip drivers  --->                           │ │
│ │          Mapping drivers for chip access  --->                      │ │
│ │          Self-contained MTD device drivers  --->                    │ │
│ │    <*>   NAND Device Support  --->                                  │ │
│ │    <*>   OneNAND Device Support  --->                               │ │
│ │          UBI - Unsorted block images  --->                          │ │
│ └─────────────────────────────────────────────────────────────────────┘ │
├─────────────────────────────────────────────────────────────────────────┤
│                    <Select>    < Exit >    < Help >                     │
└─────────────────────────────────────────────────────────────────────────┘

Select the “RAM/ROM/Flash chip drivers” and ensure CFI and Intel/Sharp are selected.

┌────────────────────── RAM/ROM/Flash chip drivers ───────────────────────┐
│  Arrow keys navigate the menu.  <Enter> selects submenus --->.          │
│  Highlighted letters are hotkeys.  Pressing <Y> includes, <N> excludes, │
│  <M> modularizes features.  Press <Esc><Esc> to exit, <?> for Help, </> │
│  for Search.  Legend: [*] built-in  [ ] excluded  <M> module  < >       │
│ ┌─────────────────────────────────────────────────────────────────────┐ │
│ │    <*> Detect flash chips by Common Flash Interface (CFI) probe     │ │
│ │    < > Detect non-CFI AMD/JEDEC-compatible flash chips              │ │
│ │    [ ] Flash chip driver advanced configuration options             │ │
│ │    <*> Support for Intel/Sharp flash chips                          │ │
│ │    < > Support for AMD/Fujitsu flash chips                          │ │
│ │    < > Support for ST (Advanced Architecture) flash chips           │ │
│ │    < > Support for RAM chips in bus mapping                         │ │
│ │    < > Support for ROM chips in bus mapping                         │ │
│ │    < > Support for absent chips in bus mapping                      │ │
│ │                                                                     │ │
│ │                                                                     │ │
│ └─────────────────────────────────────────────────────────────────────┘ │
├─────────────────────────────────────────────────────────────────────────┤
│                    <Select>    < Exit >    < Help >                     │
└─────────────────────────────────────────────────────────────────────────┘

Finally, go back to the MTD menu and select the “Mapping drivers for chip access” option. This option enables the partitioning of the MTD into four partitions: u-boot, u-boot environment, kernel, and file system.

┌──────────────────── Mapping drivers for chip access ────────────────────┐
│  Arrow keys navigate the menu.  <Enter> selects submenus --->.          │
│  Highlighted letters are hotkeys.  Pressing <Y> includes, <N> excludes, │
│  <M> modularizes features.  Press <Esc><Esc> to exit, <?> for Help, </> │
│  for Search.  Legend: [*] built-in  [ ] excluded  <M> module  < >       │
│ ┌─────────────────────────────────────────────────────────────────────┐ │
│ │    [ ] Support non-linear mappings of flash chips                   │ │
│ │    < > CFI Flash device in physical memory map                      │ │
│ │    < > CFI Flash device mapped on ARM Integrator/P720T              │ │
│ │    <*> TI OMAP board mappings                                       │ │
│ │    < > Map driver for platform device RAM (mtd-ram)                 │ │
│ │                                                                     │ │
│ │                                                                     │ │
│ └─────────────────────────────────────────────────────────────────────┘ │
├─────────────────────────────────────────────────────────────────────────┤
│                    <Select>    < Exit >    < Help >                     │
└─────────────────────────────────────────────────────────────────────────┘

Download and Build BusyBox
The source to BusyBox can be downloaded from http://www.busybox.net/downloads. Download busybox-1.20.2.tar.bz2 to the /home/user/src directory. Change directory to the build directory and extract the source code with the tar utility.
```
[root@localhost src]# cd ../build
[root@localhost build]# tar -xjvf ../src/busybox-1.20.2.tar.bz2
```
And then:
```
[root@localhost build]# cd busybox-1.20.2
[root@localhost busybox-1.2.2.1]# make menuconfig
```
To build BusyBox, simply type in make at the command line. After a few minutes the compile should be complete. When compilation is complete install BusyBox to the target directory. The make and install commands are show below:
```
[root@localhost busybox-1.2.2.1]# make
[root@localhost busybox-1.2.2.1]# make CONFIG_PREFIX=/home/user/target install
```

Configure the New Target Root File System

Looking at the newly built root file system, there are only three subdirectories of binaries and a symbolic link of bin/busybox to linuxrc. More directories must be created before the file system can be used. Some device nodes should be created, too.

[root@localhost bin]# cd /home/user/target/
[root@localhost target]# dir
total 28
drwxr-xr-x  2 root root 4096 Nov 21 10:20 bin
lrwxrwxrwx  1 root root   11 Nov 21 10:20 linuxrc -> bin/busybox
drwxr-xr-x  2 root root 4096 Nov 21 10:20 sbin
drwxr-xr-x  4 root root 4096 Nov 21 10:20 usr

Create the dev, dev/pts, etc, etc/init.d, lib, mnt, opt, proc, root, sys, tmp, var, and var/log directories. Also create the device node for the initial console.

[root@localhost target]# mkdir dev
[root@localhost target]# mknod dev/console c 5 1
[root@localhost target]# mkdir dev/pts
[root@localhost target]# mkdir etc
[root@localhost target]# mkdir etc/init.d
[root@localhost target]# mkdir lib
[root@localhost target]# mkdir mnt
[root@localhost target]# mkdir opt
[root@localhost target]# mkdir proc
[root@localhost target]# mkdir root
[root@localhost target]# mkdir sys
[root@localhost target]# mkdir tmp
[root@localhost target]# mkdir var
[root@localhost target]# mkdir var/log

To have the /proc and /dev/pts file systems mounted at boot time, the file etc/fstab must be created in the etc directory.

[root@localhost target]# cd etc
[root@localhost etc]# vi fstab
proc            /proc           proc    defaults        0 0
none            /dev/pts        devpts  mode=0622       0 0

The login utilities use the files group, hosts, and passwd in the etc directory for logging in. For now, only root needs to be defined in group and passwd while hosts just needs to have localhost defined.
```
[root@localhost etc]# vi group
root:x:0:root

[root@localhost etc]# vi passwd
root::0:0:root:/root:/bin/ash 

[root@localhost etc]# vi hosts
127.0.0.1       localhost
```

The kernel starts “/sbin/init” after it boots.Init reads the etc/inittab file to determine what to do at start up, shutdown, or when a user logs in. These inittab files can get quite complicated. A simple one is shown below:

[root@localhost etc]# vi inittab
::sysinit:/etc/init.d/rcS 

# /bin/ash
#
# Start an "askfirst" shell on the serial port
console::askfirst:-/bin/ash

# Stuff to do when restarting the init process
::restart:/sbin/init

# Stuff to do before rebooting
::ctrlaltdel:/sbin/reboot
::shutdown:/bin/umount -a -r
::shutdown:/sbin/swapoff -a

The “sysinit” line tells init to run the /etc/init.d/rcS script to set up the system.

A simple etc/init.d/rcS file could assume file systems existed in the kernel and would simply mount the mount points as needed. A more complicated one would test for the existence of file systems and if found, mount them; if not found, find ways to still get the system booted.

The author has taken the etc/init.d/rcS and mdev.conf files from the V2.6.22.18-OMAP3 release for a simple example. The rcS script will test for the existence of file systems and mount them accordingly.

[root@localhost etc]# vi init.d/rcS

#!/bin/sh
#   ---------------------------------------------
#   Common settings
#   ---------------------------------------------
HOSTNAME=OMAP3EVM
VERSION=1.0.0

hostname $HOSTNAME

#   ---------------------------------------------
#   Prints execution status.
#
#   arg1 : Execution status
#   arg2 : Continue (0) or Abort (1) on error
#   ---------------------------------------------
status ()
{
       if [ $1 -eq 0 ] ; then
               echo "[SUCCESS]"
       else
               echo "[FAILED]"

               if [ $2 -eq 1 ] ; then
                       echo "... System init aborted."
                       exit 1
               fi
       fi

}

#   ---------------------------------------------
#   Get verbose
#   ---------------------------------------------
echo ""
echo "    System initialization..."
echo ""
echo "    Hostname       : $HOSTNAME"
echo "    Filesystem     : v$VERSION"
echo ""
echo ""
echo "    Kernel release : `uname -s` `uname -r`"
echo "    Kernel version : `uname -v`"
echo ""


#   ---------------------------------------------
#   MDEV Support
#   (Requires sysfs support in the kernel)
#   ---------------------------------------------
echo -n " Mounting /proc             : "
mount -n -t proc /proc /proc
status $? 1

echo -n " Mounting /sys              : "
mount -n -t sysfs sysfs /sys
status $? 1

echo -n " Mounting /dev              : "
mount -n -t tmpfs mdev /dev
status $? 1

echo -n " Mounting /dev/pts          : "
mkdir /dev/pts
mount -t devpts devpts /dev/pts
status $? 1

echo -n " Enabling hot-plug          : "
echo "/sbin/mdev" > /proc/sys/kernel/hotplug
status $? 0

echo -n " Populating /dev            : "
mkdir /dev/input
mkdir /dev/snd

mdev -s
status $? 0

#   ---------------------------------------------
#   Disable power management
#   (Requires sysfs support in the kernel)
#   ---------------------------------------------
# echo -n " Disabling Power mgmt       : "
# echo -n "1" > /sys/power/cpuidle_deepest_state
# status $? 1

#   ---------------------------------------------
#   Turn off LCD after 1 hour of inactivity
#   (Requires sysfs support in the kernel)
#   ---------------------------------------------
# echo -n " Turn off LCD after 1 hour  : "
# echo -n "3600" > /sys/power/fb_timeout_value
# status $? 1


#   ---------------------------------------------
#   Mount the default file systems
#   ---------------------------------------------
echo -n " Mounting other filesystems : "
mount -a
status $? 0


#   ---------------------------------------------
#   Set PATH
#   ---------------------------------------------
export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin


#   ---------------------------------------------
#   Start other daemons
#   ---------------------------------------------
echo -n " Starting syslogd           : "
/sbin/syslogd
status $? 0

echo -n " Starting telnetd           : "
/usr/sbin/telnetd
status $? 0


#   ---------------------------------------------
#   Done!
#   ---------------------------------------------
echo ""
echo "System initialization complete."


#   ---------------------------------------------
#   Start demo app
#   ---------------------------------------------
#if [[ -x /etc/init.d/demo_start ]]; then
#       echo " Starting Demo Application..."
#       /etc/init.d/demo_start &
#       sleep 5
#fi
Please note that in more recent kernels (2.6.29 and newer) the sysfs entries shown above to disable power management and control the LCD inactivity timeout shown above have been removed. For latest details on using OMAP Power Management in Linux please refer to this article.

To automatically mount the debugfs on start-up the following can be added to the above rcS file. Please note that the debugfs needs to be selected in the kernel configuration and built into the kernel before you can mount it. The below script checks to see if the debugfs is supported by the kernel before attempting to mount the file-system. To enable the debugfs run "make menuconfig" and go to "Kernel Hacking" and select "Debug Filesystem".

cat /proc/filesystems | grep -q debugfs
if [ $? -eq 0 ] ; then
        echo -n " Mounting /debug             : "
        mount -n -t debugfs none /debug
        status $? 1
fi

To automatically mount the debugfs on start-up the following can be added to the above rcS file. Please note that the debugfs needs to be selected in the kernel configuration and built into the kernel before you can mount it. The below script checks to see if the debugfs is supported by the kernel before attempting to mount the file-system. To enable the debugfs run "make menuconfig" and go to "Kernel Hacking" and select "Debug Filesystem".

cat /proc/filesystems | grep -q debugfs
if [ $? -eq 0 ] ; then
        echo -n " Mounting /debug             : "
        mount -n -t debugfs none /debug
        status $? 1
fi

After saving the file, change its access permissions so that it is executable for all.

[root@localhost etc]# vi mdev.conf

audio       0:5 0666
console     0:5 0600
control.*   0:0 0660 @/bin/mv /dev/$MDEV /dev/snd/
dsp         0:5 0666
event.*     0:0 0600 @/bin/mv /dev/$MDEV /dev/input/
fb          0:5 0666
nfs         0:5 0770
null        0:0 0777
pcm.*       0:0 0660 @/bin/mv /dev/$MDEV /dev/snd/
rtc         0:0 0666
tty         0:5 0660
tty0*       0:5 0660
tty1*       0:5 0660
tty2*       0:5 0660
tty3*       0:5 0660
tty4*       0:5 0660
tty5*       0:5 0660
tty6*       0:5 0660
ttyS*       0:5 0640
urandom     0:0 0444
zero        0:0 0666

Add the Shared Libraries Applications will Require
In the Code Sourcery tool chain, most of the libraries are found in the /home/testbed/CodeSourcery/Sourcery_G++_Lite/arm-none-linux-gnueabi/libc/lib directory. Simply copy these files to the root file system, maintaining symbolic links and then strip out unneeded debug information.
```
[root@localhost user]# cd /home/user/target/lib
[root@localhost lib]# cp –r /home/testbed/CodeSourcery/Sourcery_G++_Lite/arm-none-linux-gnueabi/libc/lib/* .
[root@localhost lib]# arm-none-linux-gnueabi-strip *
```
Some libraries might be in other directories in the tool chain; those would have to be found on a “trial and error” basis when applications do not load because of a missing shared library.
Mounting the Root File System over NFS
Enhancing the Root File System
Any drivers built as modules need to be added to the target root file system
```
[root@localhost 2.6_kernel]# make modules
[root@localhost 2.6_kernel]# make INSTALL_MOD_PATH=/home/user/target modules_install
```
One problem still exists – the modules still have debug information so they are larger than they need to be. When debug information is no longer needed, use the arm-none-linux-gnueabi-strip utility to remove it.
```
[root@localhost user]# cd /home/user/target/lib/modules
[root@localhost modules]# arm-none-linux-gnueabi-strip `find . –name “*.ko”`
```

Build FAQ

Openembedded build cmake: Error running link command: No such file or directory

The errors are:

| Linking CXX static library libcmsys.a
| cd /home/testbed/oe/arago-tmp/work/armv5te-none-linux-gnueabi/cmake-2.8.3-r2.1/cmake-2.8.3/Source/kwsys && /home/testbed/oe/arago-tmp/sysroots/i686-linux/usr/bin/cmake -P CMakeFiles/cmsys.dir/cmake_clean_target.cmake
| cd /home/testbed/oe/arago-tmp/work/armv5te-none-linux-gnueabi/cmake-2.8.3-r2.1/cmake-2.8.3/Source/kwsys && /home/testbed/oe/arago-tmp/sysroots/i686-linux/usr/bin/cmake -E cmake_link_script CMakeFiles/cmsys.dir/link.txt --verbose=1
| CMAKE_AR-NOTFOUND cr libcmsys.a  CMakeFiles/cmsys.dir/ProcessUNIX.o CMakeFiles/cmsys.dir/Base64.o CMakeFiles/cmsys.dir/MD5.o CMakeFiles/cmsys.dir/Terminal.o CMakeFiles/cmsys.dir/System.o CMakeFiles/cmsys.dir/String.o CMakeFiles/cmsys.dir/Directory.o CMakeFiles/cmsys.dir/DynamicLoader.o CMakeFiles/cmsys.dir/Glob.o CMakeFiles/cmsys.dir/RegularExpression.o CMakeFiles/cmsys.dir/SystemTools.o CMakeFiles/cmsys.dir/CommandLineArguments.o CMakeFiles/cmsys.dir/Registry.o CMakeFiles/cmsys.dir/IOStream.o CMakeFiles/cmsys.dir/SystemInformation.o
| Error running link command: No such file or directory
| make[2]: *** [Source/kwsys/libcmsys.a] Error 2
| make[2]: Leaving directory `/home/testbed/oe/arago-tmp/work/armv5te-none-linux-gnueabi/cmake-2.8.3-r2.1/cmake-2.8.3'
| make[1]: *** [Source/kwsys/CMakeFiles/cmsys.dir/all] Error 2
| make[1]: Leaving directory `/home/testbed/oe/arago-tmp/work/armv5te-none-linux-gnueabi/cmake-2.8.3-r2.1/cmake-2.8.3'
| make: *** [all] Error 2
| FATAL: oe_runmake failed
| ERROR: Function do_compile failed
NOTE: package cmake-2.8.3-r2.1: task do_compile: Failed
ERROR: TaskFailed event exception, aborting
ERROR: Build of /home/testbed/oe/arago-oe-dev/recipes/cmake/cmake_2.8.3.bb do_compile failed
ERROR: Task 15 (/home/testbed/oe/arago-oe-dev/recipes/cmake/cmake_2.8.3.bb, do_compile) failed with exit code 1
ERROR: '/home/testbed/oe/arago-oe-dev/recipes/cmake/cmake_2.8.3.bb' failed
ERROR: '/home/testbed/oe/arago-oe-dev/recipes/cmake/cmake_2.8.3.bb' failed

To do add the arm-none-linux-gnueabi-ar path to the CMAKE_FIND_ROOT_PATH
In the file: /home/testbed/oe/arago-oe-dev/classes/cmake.bbclass

echo "set( CMAKE_FIND_ROOT_PATH ${STAGING_DIR_HOST} ${STAGING_DIR_NATIVE} ${STAGING_DIR_NATIVE}${prefix_native}/${BASE_PACKAGE_ARCH} "/home/testbed/CodeSourcery/Sourcery_G++_Lite" )" >> ${WORKDIR}/toolchain.cmake

Openembedded build cmake: bin/ld: cannot find libncurses.so.5

The errors are like:

oe/build-minimal-uclibc/minimal-uclibc-dev/sysroots/i686-linux/usr/armv7a/lib/gcc/arm-oe-linux-uclibceabi/4.5.3/../../../../arm-oe-linux-uclibceabi/bin/ld: skipping incompatible /oe/build-minimal-uclibc/minimal-uclibc-dev/sysroots/i686-linux/usr/lib/libexpat.so when searching for -lexpat
        /oe/build-minimal-uclibc/minimal-uclibc-dev/sysroots/i686-linux/usr/armv7a/lib/gcc/arm-oe-linux-uclibceabi/4.5.3/../../../../arm-oe-linux-uclibceabi/bin/ld: skipping incompatible /oe/build-minimal-uclibc/minimal-uclibc-dev/sysroots/i686-linux/usr/lib/libexpat.a when searching for -lexpat
        /oe/build-minimal-uclibc/minimal-uclibc-dev/sysroots/i686-linux/usr/armv7a/lib/gcc/arm-oe-linux-uclibceabi/4.5.3/../../../../arm-oe-linux-uclibceabi/bin/ld: skipping incompatible /oe/build-minimal-uclibc/minimal-uclibc-dev/sysroots/i686-linux/usr/lib/libz.so when searching for -lz
        /oe/build-minimal-uclibc/minimal-uclibc-dev/sysroots/i686-linux/usr/armv7a/lib/gcc/arm-oe-linux-uclibceabi/4.5.3/../../../../arm-oe-linux-uclibceabi/bin/ld: skipping incompatible /oe/build-minimal-uclibc/minimal-uclibc-dev/sysroots/i686-linux/usr/lib/libz.a when searching for -lz
        /oe/build-minimal-uclibc/minimal-uclibc-dev/sysroots/i686-linux/usr/armv7a/lib/gcc/arm-oe-linux-uclibceabi/4.5.3/../../../../arm-oe-linux-uclibceabi/bin/ld: skipping incompatible /oe/build-minimal-uclibc/minimal-uclibc-dev/sysroots/i686-linux/usr/lib/libcurl.so when searching for -lcurl
        /oe/build-minimal-uclibc/minimal-uclibc-dev/sysroots/i686-linux/usr/armv7a/lib/gcc/arm-oe-linux-uclibceabi/4.5.3/../../../../arm-oe-linux-uclibceabi/bin/ld: skipping incompatible /oe/build-minimal-uclibc/minimal-uclibc-dev/sysroots/i686-linux/usr/lib/libcurl.a when searching for -lcurl
        /oe/build-minimal-uclibc/minimal-uclibc-dev/sysroots/i686-linux/usr/armv7a/lib/gcc/arm-oe-linux-uclibceabi/4.5.3/../../../../arm-oe-linux-uclibceabi/bin/ld: skipping incompatible /oe/build-minimal-uclibc/minimal-uclibc-dev/sysroots/i686-linux/usr/lib/libncurses.so.5 when searching for libncurses.so.5
        /oe/build-minimal-uclibc/minimal-uclibc-dev/sysroots/i686-linux/usr/armv7a/lib/gcc/arm-oe-linux-uclibceabi/4.5.3/../../../../arm-oe-linux-uclibceabi/bin/ld: cannot find libncurses.so.5

To do Miss the DEPENDS: ncures, add `ncurses` to `DEPENDS`

--- a/recipes/cmake/cmake_2.8.3.bb
+++ b/recipes/cmake/cmake_2.8.3.bb
@@ -4,7 +4,7 @@ PR = "${INC_PR}.1"

 inherit cmake

-DEPENDS += "curl expat zlib libarchive"
+DEPENDS += "curl expat zlib libarchive ncurses"

 SRC_URI[md5sum] = "a76a44b93acf5e3badda9de111385921"
 SRC_URI[sha256sum] = "689ed02786b5cefa5515c7716784ee82a82e8ece6be5a3d629ac3cc0c05fc288"

Openembedded: hang after this line "hwclock: can't open '/dev/misc/rtc':"

The system ends up with hang after:

INIT: version 2.86 booting
Please wait: booting...
Starting udev

Root filesystem already rw, not remounting
logger: mount: mount point /proc/bus/usb does not exist
Caching udev devnodes
Populating dev cache
ALSA: Restoring mixer settings...
/usr/sbin/alsactl: load_state:1625: No soundcards found...
Configuring network interfaces... ifconfig: SIOCGIFFLAGS: No such device
ifconfig: SIOCGIFFLAGS: No such device
eth0      No such device

ifconfig: SIOCGIFFLAGS: No such device
done.
Starting portmap daemon: portmapportmap: fork: No such device.
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.all.rp_filter = 1
hwclock: can't open '/dev/misc/rtc': No such file or directory
Tue Mar 13 20:12:00 UTC 2012
hwclock: can't open '/dev/misc/rtc': No such file or directory

To fix the problem, follow those steps:¹^,²

1. Go to udev receipes
$ cd ~/oe/openembedded/recipes/udev

2. Delete file udev_171.bb
$ rm udev_171.bb

3. Modify file udev_git.bb
Change PV = "171" to be PV = "162" (may older, the linux 2.6.37 uses the 141)

4. Modify ~/oe/openembedded/conf/distro/include/angstrom-2010-preferred-versions.inc
change from
PREFERRED_VERSION_udev = "171"
to
PREFERRED_VERSION_udev = "162"

5. Re-build udev
$ bitbake -f udev -c clean
$ bitbake -f udev -c configure     or (use task-base to replace task-base-extended)
Go to udev work directory and delete this portion from Makefile.am

                # ------------------------------------------------------------------------------

                # Bluetooth HID devices with special magic to switch the device

                # ------------------------------------------------------------------------------

                extras_hid2hci_hid2hci_SOURCES = extras/hid2hci/hid2hci.c

                extras_hid2hci_hid2hci_CPPFLAGS = $(AM_CPPFLAGS) $(LIBUSB_CFLAGS)

                extras_hid2hci_hid2hci_LDADD = libudev/libudev-private.la $(LIBUSB_LIBS)

                dist_udevrules_DATA += extras/hid2hci/70-hid2hci.rules

                libexec_PROGRAMS += extras/hid2hci/hid2hci

$ bitbake -f udev

6. We also need to fix udev verion 171 dependency from previous bitbake otherwise you will see this error
|  * satisfy_dependencies_for: Cannot satisfy the following dependencies for task-base:
|  *    libudev0 (>= 171) *
|  * opkg_install_cmd: Cannot install package task-base.

To find out what packages need to rebuild
cd /home/infocast35/stuff/build/tmp/deploy/eglibc/ipk/armv5te
$ for f in *.ipk; do ar p $f control.tar.gz | tar -zxO ./control|grep "libudev0 (>= 171)" && ls $f; done

Depends: libusb-0.1-4 (>= 0.1.3), libusb-1.0-0 (>= 1.0.8), libc6 (>= 2.12), libglib-2.0-0 (>= 2.28.5), libdbus-1-3 (>= 1.4.1), libreadline5 (>= 5.2), libudev0 (>= 171)
bluez4_4.98-r8.0.9_armv7a.ipk......

7. clean some packages
$ bitbake -f bluez4 -c clean
$ bitbake -f gstreamer -c clean
$ bitbake -f gst-plugins-base -c clean

8. ReRun
$ bitbake -c clean xxx-image
$ bitbake xxx-image

Note:

udev 169 and up require kernel 2.6.36 for ARM
udev 162 may have conflict with bluez and hid2hci, may need to implement this fix http://git.kernel.org/?p=linux/hotplug/udev.git;a=commitdiff;h=07f1d2860e8ee393abaaead75a6ab3af0f10efbb

Openembedded build: Cannot satisfy the following dependencies for task-base

Sometimes its required to downgrade a package version e.g. you are suspecting that the problem is caused by udev version 171 so you would like to build a root file system incrementally using udev 164

So you do required rituals of selecting 164 version of udev using PREFERRED_VERSION_udev = “164″

and then bitbake <your image>

and expectedly it should build your image again with udev 164 in it but it may not happen and you might end up with errors like

| Configuring udev.
| Configuring task-base-extended.
| Configuring sysvinit-pidof.
| Configuring tinylogin.
| Configuring sysvinit.
| Collected errors:
|  * satisfy_dependencies_for: Cannot satisfy the following dependencies for task-base:
|  *    libudev0 (>= 171) *
|  * opkg_install_cmd: Cannot install package task-base.
| ERROR: Function ‘do_rootfs’ failed (see /home/kraj/work/angstrom/build/tmp-angstrom_2010_x-uclibc/work/qemumips-angstrom-linux-uclibc/console-image-1.0-r0/temp/log.do_rootfs.15163 for further information)
NOTE: package console-image-1.0-r0: task do_rootfs: Failed
ERROR: Task 8 (/home/kraj/work/angstrom/sources/meta-angstrom/recipes-angstrom/images/console-image.bb, do_rootfs) failed with exit code ’1′
ERROR:
‘/home/kraj/work/angstrom/sources/meta-angstrom/recipes-angstrom/images/console-image.bb’
failed

The problem here is that there is a package which has created a dependency on libudev0 >= 171 but now we are sysrooting with 164. Ideally bitbake should have noticed it and rebuilt the concerned recipe but it does not happen

To do

You need to figure out with package is wanting libudev0 171+

$cd /home/testbed/oe/build/tmp-angstrom_2010_x/deploy/eglibc/ipk/armv7a
$ for f in *.ipk; do ar p $f control.tar.gz | tar -zxO ./control|grep“libudev0 (>= 171)” && ls $f; done

Depends: libusb-0.1-4 (>= 0.1.3), libusb-1.0-0 (>= 1.0.8), libc6 (>= 2.12), libglib-2.0-0 (>= 2.28.5), libdbus-1-3 (>= 1.4.1), libreadline5 (>= 5.2), libudev0 (>= 171)
bluez4_4.98-r8.0.9_armv7a.ipk
Depends: libgstinterfaces-0.10-0 (>= 0.10.32), gstreamer (>= 0.10.32), libgmodule-2.0-0 (>= 2.28.5), libxml2 (>= 2.7.8), libz1 (>= 1.2.3), libc6 (>= 2.12), libsm6 (>= 1.2.0), libuuid1 (>= 2.18), libice6 (>= 1.0.7), libxv1 (>= 1.0.6), libxext6 (>= 1.3.0), libx11-6 (>= 1.4.3), libxcb1 (>= 1.6), libpthread-stubs0 (>= 0.2), libxau6 (>= 1.0.6), libxdmcp6 (>= 1.1.0), libgudev-1.0-0 (>= 171), libudev0 (>= 171), libgobject-2.0-0 (>= 2.28.5), libgthread-2.0-0 (>= 2.28.5), libglib-2.0-0 (>= 2.28.5)
gst-plugin-video4linux_0.10.32-r11.1.9_armv7a.ipk => gst-plugins 
Depends: libdrm2 (>= 2.4.25), libc6 (>= 2.12), libkms1 (>= 2.4.25), libcairo2 (>= 1.10.0), libpixman-1-0 (>= 0.22.0), libfontconfig1 (>= 2.8.0), libexpat1 (>= 2.0.1), libfreetype6 (>= 2.4.3), libpng12-0 (>= 1.2.46), libxrender1 (>= 0.9.6), libx11-6 (>= 1.4.3), libxcb1 (>= 1.6), libpthread-stubs0 (>= 0.2), libxau6 (>= 1.0.6), libxdmcp6 (>= 1.1.0), libz1 (>= 1.2.3), libudev0 (>= 171)
libdrm-tests_2.4.25-r0.9_armv7a.ipk

So you know now the ipk which is depending on udev 171 and is being pulled into the image

$ bitbake -f bluez4 -c clean
$ bitbake -f gstreamer -c clean
$ bitbake -f gst-plugins-base -c clean

Footnotes:

http://www.purinux.org/blog/2012/03/openembedded-hang-after-this-line-hwclock-cant-open-devmiscrtc.html

http://www.purinux.org/blog/2012/03/how-to-create-oe-for-infocast35.html

Filesystem OverView

Table of Contents

General

arago main page

angstrom

busybox

ubuntu

OpenEmbedded

Poky Linux

Root File system solutions

Creating a Root File System for Linux on OMAP35x

Initrd

Modify

Using The Correct Console Device

Arago

Setting Up Build Environment and build

Crosscompiling Outside of Arago

Creating recipes in Arago

Angstrom

Build

Host and Target

Notes

Creating a Root File System for Linux on OMAP35x

Build FAQ

Openembedded build cmake: Error running link command: No such file or directory

Openembedded build cmake: bin/ld: cannot find libncurses.so.5

Openembedded: hang after this line "hwclock: can't open '/dev/misc/rtc':"

Openembedded build: Cannot satisfy the following dependencies for task-base

Footnotes: