From 5b8301a3b835890808e22d0fe34caac5ae5071d6 Mon Sep 17 00:00:00 2001 From: Scott Rifenbark Date: Wed, 27 Jul 2011 10:39:56 -0700 Subject: documentation/dev-manual/dev-manual-cases.xml: generalized the BSP case Because the BSP example is now in an appendix, I re-wrote this section to overview the case. (From yocto-docs rev: c0d88c6050bd17d65d8fe8c8abb227998fd4c11e) Signed-off-by: Scott Rifenbark Signed-off-by: Richard Purdie --- documentation/dev-manual/dev-manual-cases.xml | 842 +++++--------------------- 1 file changed, 155 insertions(+), 687 deletions(-) (limited to 'documentation') diff --git a/documentation/dev-manual/dev-manual-cases.xml b/documentation/dev-manual/dev-manual-cases.xml index 28d48d0c9e..ebc8eeca1e 100644 --- a/documentation/dev-manual/dev-manual-cases.xml +++ b/documentation/dev-manual/dev-manual-cases.xml @@ -14,6 +14,11 @@ target hardware. + + This chapter presents an overview of the primary cases. + Supsequent appendices in the manual provide detailed explanations of the examples. + + [WRITERS NOTE: What is undetermined at this point is how much of the entire development process we include in this particular chapter. @@ -52,702 +57,165 @@ see Yocto Project Terms in this manual. + + The remainder of this section presents the basic steps to create a BSP basing it on an + existing BSP that ships with the Yocto Project. + You can reference BSP Development Case + for a detailed example that uses the Crown Bay BSP as a base BSP from which to start. + + Here are the basic steps involved in creating a BSP: - Be sure your host development system is set up to support - development using the Yocto Project. - See + Set up your host development system to support + development using the Yocto Project: See The Linux Distributions section and The Packages section both in the Yocto Project Quick Start for requirements. You will also need a release of Yocto Project installed on the host. - Choose a BSP available with Yocto Project that most closely represents - your hardware. - Get set up with a base BSP. - Make a copy of the existing BSP and isolate your work by creating a layer - for your recipes. - Make configuration and recipe changes to your new BSP layer. - Prepare for the build. - Select and configure the kernel. - Identify the machine branch. - Build the image. + Establish a local copy of the Yocto Project files on your + system: You need to have the Yocto Project files available on your host system. + Having the Yocto Project files on your system gives you access to the build + process and tools you need. + For information on how to get these files, see the + Getting Setup section in this manual. + Choose a Yocto Project-supported BSP as your base BSP: + The Yocto Project ships with several BSPs that support various hardware. + It is best to base your new BSP on an existing BSP rather than create all the + recipes and configuration files from scratch. + While it is possible to create everything from scratch, basing your new BSP + on something that is close is much easier. + Or, at a minimum, it gives you some structure with which to start. + At this point you need to understand your target hardware well enough to determine which + existing BSP it most closely matches. + Things to consider are your hardware’s on-board features such as CPU type and graphics support. + You should look at the README files for supported BSPs to get an idea of which one + you could use. + A generic Atom-based BSP to consider is the Crown Bay that does not support + the Intel® Embedded Media Graphics Driver (EMGD). + The remainder of this example uses that base BSP. + To see the supported BSPs, go to the Yocto Project + download page and click + on “BSP Downloads.” + Establish a local copy of the base BSP files: Having + the BSP files on your system gives you access to the build + process and tools you need. + For information on how to get these files, see + Getting Setup earlier in this manual. + Create your own BSP layer: Layers are ideal for + isolating and storing work for a given piece of hardware. + A layer is really just a location or area in which you place the recipes for your BSP. + In fact, a BSP is, in itself, a special type of layer. + Consider an application as another example that illustrates a layer. + Suppose you are creating an application that has library or other dependencies in + order for it to compile and run. + The layer, in this case, would be where all the recipes that define those dependencies + are kept. The key point for a layer is that it is an isolated area that contains + all the relevant information for the project that the Yocto Project build + system knows about. + The Yocto Project supports four BSPs that are part of the + Yocto Project release: atom-pc, beagleboard, + mpc8315e, and routerstationpro. + The recipes and configurations for these four BSPs are located and dispersed + within local Yocto Project files. + Consequently, they are not totally isolated in the spirit of layers unless you think + of meta-yocto as a layer itself. + On the other hand, BSP layers for Crown Bay, Emenlow, Jasper Forest, + N450, and Sugar Bay are isolated. + When you set up a layer for a new BSP you should follow a standard layout. + This layout is described in the + + Example Filesystem Layout section of the Board Support Package (BSP) Development + Guide. + In the standard layout you will notice a suggested structure for recipes and + configuration information. + You can see the standard layout for the Crown Bay BSP in this example by examining the + directory structure of the meta-crownbay layer inside the + local Yocto Project files. + Make configuration and recipe changes to your new BSP + layer: The standard BSP layer structure organizes the files you need to edit in + conf and several recipes-* within the + BSP layer. + Configuration changes identify where your new layer is on the local system + and identify which kernel you are going to use. + Recipe changes include altering recipes (.bb files), removing + recipes you don't use, and adding new recipes that you need to support your hardware. + + Prepare for the build: Once you have made all the + changes to your BSP layer there remains a few things + you need to do for the Yocto Project build system in order for it to create your image. + You need to get the build environment ready by sourcing an environment setup script + and you need to be sure two key configuration files are configured appropriately. + The entire process for building an image is overviewed in the + + Building an Image section of the Yocto Project Quick Start. + You might want to reference this information. + Build the image: The Yocto Project uses the BitBake + tool to build images based on the type of image + you want to create. + You can find more information on BitBake + here. + The build process supports several types of images to satisfy different needs. + When you issue the BitBake command you provide a “top-level” recipe that essentially + starts the process off of building the type of image you want. + [WRITER'S NOTE: Consider moving this to the Poky Reference Manual.] + You can find these recipes in the meta/recipes-core/images and + meta/recipes-sato/images directories of your local Yocto Project + file structure (Git repository or extracted release tarball). + Although the recipe names are somewhat explanatory, here is a list that describes them: + + Base – A foundational basic image without support + for X that can be reasonably used for customization. + Core – A foundational basic image with support for + X that can be reasonably used for customization. + Direct Disk – An image that you can copy directory to + the disk of the target device. + Live – An image you can run from a USB device or from + a CD without having to first install something. + Minimal – A small image without a GUI. + This image is not much more than a kernel with a shell. + Minimal Development – A Minimal image suitable for + development work. + Minimal Direct Disk – A Minimal Direct + Disk image. + Minimal RAM-based Initial Root Filesystem – + A minimal image + that has the initramfs as part of the kernel, which allows the + system to find the first “init” program more efficiently. + Minimal Live – A Minimal Live image. + Minimal MTD Utilities – A minimal image that has support + for the MTD utilities, which let the user interact with the MTD subsystem in + the kernel to perform operations on flash devices. + Sato – An image with Sato support, a mobile environment + and visual style that works well with mobile devices. + Sato Development – A Sato image suitable for + development work. + Sato Direct Disk – A Sato Direct + Disk image. + Sato Live – A Sato Live image. + Sato SDK – A Sato image that includes the Yocto Project + toolchain and development libraries. + Sato SDK Direct Disk – A Sato SDK Direct + Disk image. + Sato SDK Live – A Sato SDK Live + image. + + - You can view a video presentation of the BSP creation process - here. - You can also find supplemental information in the - - Board Support Package (BSP) Development Guide. - Finally, there is wiki page write up of the example located - - here you might find helpful. -
- Setting Up Yocto Project - - - You need to have the Yocto Project files available on your host system. - You can get files through tarball extraction or by cloning the poky - Git repository. - Typically, cloning the Git repository is the method to use. - This allows you to maintain a complete history of changes and facilitates you - contributing back to the Yocto Project. - However, if you just want a hierarchical file structure that contains the recipes - and metadata that let you develop you can download tarballs from the - download page. - - - - Regardless of the method you use this manual will refer to the resulting - hierarchical set of files as "the local Yocto Project files." - - - - [WRITER'S NOTE: I need to substitute correct and actual filenames for the - 1.1 release throughout this example once they become available.] - - - - If you download a tarball you can extract it into any directory you want using the - tar command. - For example, the following command extracts the Yocto Project 1.1 release tarball - into the current working directory and sets up a file structure whose top-level - directory is named poky-1.1: - - $ tar xfj poky-1.1.tar.bz2 - - - - - The following transcript shows how to clone the poky Git repository - into the current working directory. - The command creates the repository in a directory named poky: - - $ git clone git://git.yoctoproject.org/poky - Initialized empty Git repository in /home/scottrif/poky/.git/ - remote: Counting objects: 107624, done. - remote: Compressing objects: 100% (37128/37128), done. - remote: Total 107624 (delta 73393), reused 99851 (delta 67287) - Receiving objects: 100% (107624/107624), 69.74 MiB | 483 KiB/s, done. - Resolving deltas: 100% (73393/73393), done. - - - - - Once you have the local poky Git repository set up, - you have many development branches from which you can work. - From inside the repository you can see the branch names and the tag names used - in the Git repository using either of the following two commands: - - $ git branch -a - $ git tag -l - - For this example we are going to use the Yocto Project 1.1 Release, - which maps to the 1.1 branch in the repository. - These commands create a local branch named 1.1 - that tracks the remote branch of the same name. - - - $ cd poky - $ git checkout -b 1.1 origin/1.1 - Switched to a new branch '1.1' - - -
- -
- Choosing a Base BSP - - - The Yocto Project ships with several BSPs that support various hardware. - It is best to base your new BSP on an existing BSP rather than create all the - recipes and configuration files from scratch. - While it is possible to create everything from scratch, basing your new BSP - on something that is close is much easier. - Or, at a minimum, it gives you some structure with which to start. - - - - At this point you need to understand your target hardware well enough to determine which - existing BSP it most closely matches. - Things to consider are your hardware’s on-board features such as CPU type and graphics support. - You should look at the README files for supported BSPs to get an idea of which one - you could use. - A generic Atom-based BSP to consider is the Crown Bay that does not support - the Intel® Embedded Media Graphics Driver (EMGD). - The remainder of this example uses that base BSP. - - - - To see the supported BSPs, go to the Yocto Project - download page and click - on “BSP Downloads.” - -
- -
- Getting Your Base BSP - - - You need to have the base BSP layer on your development system. - Like the local Yocto Project files, you can get the BSP - layer one of two ways: - download the BSP tarball and extract it, or set up a local Git repository that - has the Yocto Project BSP layers. - You should use the same method that you used to get the local Yocto Project files earlier. - - - - If you are using tarball extraction, simply download the tarball for the base - BSP you chose in the previous step and then extract it into any directory - you choose using the tar command. - Upon extraction, the BSP source directory (layer) will be named - meta-<BSP_name>. - The following command extracts the Crown Bay BSP into the current directory and names it - meta-crownbay: - - $ tar xjf crownbay-noemgd-1.1.tar.bz2 - - - - - If you cloned a poky Git repository - then you need to set up a different local Git repository - (meta-intel) for the BSP. - The meta-intel Git repository contains all the metadata - that supports BSP creation. - When you set up the meta-intel Git repository you can - set it up anywhere you want. - We will set up the repository inside the - poky Git repository in this example. - - - - The following transcript shows the steps to clone the meta-intel - Git repository inside the poky Git repository created earlier in this - example. - - $cd poky - $ git clone git://git.yoctoproject.org/meta-intel.git - Initialized empty Git repository in /home/scottrif/poky/meta-intel/.git/ - remote: Counting objects: 1325, done. - remote: Compressing objects: 100% (1078/1078), done. - remote: Total 1325 (delta 546), reused 85 (delta 27) - Receiving objects: 100% (1325/1325), 1.56 MiB | 330 KiB/s, done. - Resolving deltas: 100% (546/546), done. - - - - - Because meta-intel is its own Git repository you will want - to be sure you are in the appropriate branch for your work. - For this example we are going to use the 1.1 branch. - - $ cd meta-intel - $ git checkout -b 1.1 origin/1.1 - Switched to a new branch 'bernard' - - -
- -
- Making a Copy of the Base BSP to Create Your New BSP Layer - - - Now that you have the local Yocto Project files and the base BSP files you need to create a - new layer for your BSP. - - - - Layers are ideal for isolating and storing work for a given piece of hardware. - A layer is really just a location or area in which you place the recipes for your BSP. - In fact, a BSP is, in itself, a special type of layer. - Consider an application as another example that illustrates a layer. - Suppose you are creating an application that has library or other dependencies in - order for it to compile and run. - The layer, in this case, would be where all the recipes that define those dependencies - are kept. The key point for a layer is that it is an isolated area that contains - all the relevant information for the project that the Yocto Project build system knows about. - - - - The Yocto Project supports four BSPs that are part of the - Yocto Project release: atom-pc, beagleboard, - mpc8315e, and routerstationpro. - The recipes and configurations for these four BSPs are located and dispersed - within local Yocto Project files. - Consequently, they are not totally isolated in the spirit of layers unless you think - of meta-yocto as a layer itself. - On the other hand, BSP layers for Crown Bay, Emenlow, Jasper Forest, - N450, and Sugar Bay are isolated. - - - - When you set up a layer for a new BSP you should follow a standard layout. - This layout is described in the - - Example Filesystem Layout section of the Board Support Package (BSP) Development - Guide. - In the standard layout you will notice a suggested structure for recipes and - configuration information. - You can see the standard layout for the Crown Bay BSP in this example by examining the - directory structure of the meta-crownbay layer inside the - local Yocto Project files. - - - - To create your BSP layer you simply copy the meta-crownbay - layer to a new layer. - For this example the new layer will be named meta-mymachine. - The name must follow the BSP layer naming convention, which is - meta-<name>. - The following example assumes your working directory is meta-intel - inside the local Yocto Project files. - If you downloaded and expanded a Crown Bay tarball then you simply copy the resulting - meta-crownbay directory structure to a location of your choice. - Good practice for a Git repository, however, is to just copy the new layer alongside - the existing - BSP layers in the meta-intel Git repository: - - $ cp -a meta-crownbay/ meta-mymachine - - -
- -
- Making Changes to Your BSP - - - Right now you have two identical BSP layers with different names: - meta-crownbay and meta-mymachine. - You need to change your configurations so that they work for your new BSP and - your particular hardware. - We will look first at the configurations, which are all done in the layer’s - conf directory. - - - - First, since in this example the new BSP will not support EMGD we will get rid of the - crownbay.conf file and then rename the - crownbay-noemgd.conf file to mymachine.conf. - Much of what we do in the configuration directory is designed to help the Yocto Project - build system work with the new layer and to be able to find and use the right software. - The following two commands result in a single machine configuration file named - mymachine.conf. - - $ rm meta-mymachine/conf/machine/crownbay.conf - $ mv meta-mymachine/conf/machine/crownbay-noemgd.conf \ - meta-mymachine/conf/machine/mymachine.conf - - - - - The next step makes changes to mymachine.conf itself. - The only changes needed for this example are changes to the comment lines. - Here we simply substitute the Crown Bay name with an appropriate name. - - - - Note that inside the mymachine.conf is the - PREFERRED_PROVIDER_virtual/kernel statement. - This statement identifies the kernel that the BSP is going to use. - In this case the BSP is using linux-yocto, which is the - current Linux Yocto kernel based on the Linux 2.6.37 release. - - - - The next configuration file in the new BSP layer we need to edit is layer.conf. - This file identifies build information needed for the new layer. - You can see the - - Layer Configuration File section in the Board Support Packages (BSP) Development Guide - for more information on this configuration file. - Basically, we are changing the existing statements to work with our BSP. - - - - The file contains these statements that reference the Crown Bay BSP: - - BBFILE_COLLECTIONS += "crownbay" - BBFILE_PATTERN_crownbay := "^${LAYERDIR}/" - BBFILE_PRIORITY_crownbay = "6" - - - - - Simply substitute the machine string name crownbay - with the new machine name mymachine to get the following: - - BBFILE_COLLECTIONS_mymachine += "mymachine" - BBFILE_PATTERN_mymachine := "^${LAYERDIR}/" - BBFILE_PRIORITY_mymachine = "6" - - - - - Now we will take a look at the recipes in your new layer. - The standard BSP structure has areas for BSP, graphics, core, and kernel recipes. - When you create a BSP you use these areas for appropriate recipes and append files. - Recipes take the form of .bb files. - If you want to leverage the existing recipes the Yocto Project build system uses - but change those recipes you can use .bbappend files. - All new recipes and append files for your layer must go in the layer’s - recipes-bsp, recipes-kernel, - recipes-core, and - recipes-graphics directories. - - - - First, let's look at recipes-bsp. - For this example we are not adding any new BSP recipes. - And, we only need to remove the formfactor we do not want and change the name of - the remaining one that doesn't support EMGD. - These commands take care of the recipes-bsp recipes: - - $ rm ‐rf meta-mymachine/recipes-graphics/xorg-xserver/*emgd* - $ mv meta-mymachine/recipes-bsp/formfactor/formfactor/crownbay-noemgd/ \ - meta-mymachine/recipes-bsp/formfactor/formfactor/mymachine - - - - - Now let's look at recipes-graphics. - For this example we want to remove anything that supports EMGD and - be sure to rename remaining directories appropriately. - The following commands clean up the recipes-graphics directory: - - $ rm ‐rf meta-mymachine/recipes-graphics/xorg-xserver/xserver-xf86-emgd* - $ rm ‐rf meta-mymachine/recipes-graphics/xorg-xserver/xserver-xf86-config/crownbay - $ mv meta-mymachine/recipes-graphics/xorg-xserver/xserver-xf86-config/crownbay-noemgd \ - meta-mymachine/recipes-graphics/xorg-xserver/xserver-xf86-config/mymachine - - - - - At this point the recipes-graphics directory just has files that - support Video Electronics Standards Association (VESA) graphics modes and not EMGD. - - - - Now let's look at changes in recipes-core. - The file task-core-tools.bbappend in - recipes-core/tasks appends the similarly named recipe - located in the local Yocto Project files at - meta/recipes-core/tasks. - The "append" file in our layer right now is Crown Bay-specific and supports - EMGD and non-EMGD. - Here are the contents of the file: - - RRECOMMENDS_task-core-tools-profile_append_crownbay = " systemtap" - RRECOMMENDS_task-core-tools-profile_append_crownbay-noemgd = " systemtap" - - - - - The RRECOMMENDS statements list packages that - extend usability. - The first RRECOMMENDS statement can be removed, while the - second one can be changed to reflect meta-mymachine: - - RRECOMMENDS_task-core-tools-profile_append_mymachine = " systemtap" - - - - - Finally, let's look at recipes-kernel changes. - Recall that the BSP uses the linux-yocto kernel as determined - earlier in the mymachine.conf. - The recipe for that kernel is not located in the - BSP layer but rather in the local Yocto Project files at - meta/recipes-kernel/linux and is - named linux-yocto-2.6.37.bb. - The SRCREV_machine and SRCREV_meta - statements point to the exact commits used by the Yocto Project development team - in their source repositories that identify the right kernel for our hardware. - - - - However, in the meta-mymachine layer in - recipes-kernel/linux resides a .bbappend - file named linux-yocto-2.6.37.bbappend that - is appended to the recipe of the same name in meta/recipes-kernel/link. - Thus, the SRCREV statements in the "append" file override - the more general statements found in meta. - - - - The SRCREV statements in the "append" file currently identify - the kernel that supports the Crown Bay BSP with and without EMGD support. - Here are the statements: - - SRCREV_machine_pn-linux-yocto_crownbay ?= \ - "372c0ab135978bd8ca3a77c88816a25c5ed8f303" - SRCREV_meta_pn-linux-yocto_crownbay ?= \ - "d5d3c6480d61f83503ccef7fbcd765f7aca8b71b" - - SRCREV_machine_pn-linux-yocto_crownbay-noemgd ?= \ - "372c0ab135978bd8ca3a77c88816a25c5ed8f303" - SRCREV_meta_pn-linux-yocto_crownbay-noemgd ?= \ - "d5d3c6480d61f83503ccef7fbcd765f7aca8b71b" - - - - - You will notice that there are two pairs of SRCREV statements. - The top pair identifies the kernel that supports - EMGD, which we don’t care about in this example. - The bottom pair identifies the kernel that we will use: - linux-yocto. - At this point though, the unique commit strings all are still associated with - Crown Bay and not meta-mymachine. - - - - To fix this situation in linux-yocto-2.6.37.bbappend - we delete the two SRCREV statements that support - EMGD (the top pair). - We also change the remaining pair to specify mymachine - and insert the commit identifiers to identify the kernel in which we - are interested, which will be based on the atom-pc-standard - kernel. - Here are the final SRCREV statements: - - SRCREV_machine_pn-linux-yocto-_mymachine ?= \ - "fce17f046d3756045e4dfb49221d1cf60fcae329" - SRCREV_meta_pn-linux-yocto-stable_mymachine ?= \ - "84f1a422d7e21fbc23a687035bdf9d42471f19e0" - - - - - If you are familiar with Git repositories you probably won’t have trouble locating the - exact commit strings in the Yocto Project source repositories you need to change - the SRCREV statements. - You can find all the machine and meta - branch points (commits) for the linux-yocto-2.6.37 kernel - here. - - - - If you need a little more assistance after going to the link then do the following: - - Expand the list of branches by clicking […] - Click on the yocto/standard/common-pc/atom-pc - branch - Click on the commit column header to view the top commit - Copy the commit string for use in the - linux-yocto-2.6.37.bbappend file - - - - - For the SRCREV statement that points to the meta - branch use the same procedure except expand the meta - branch in step 2 above. - - - - Also in the linux-yocto-2.6.37.bbappend file are - COMPATIBLE_MACHINE, KMACHINE, - and KERNEL_FEATURES statements. - Two sets of these exist: one set supports EMGD and one set does not. - Because we are not interested in supporting EMGD those three can be deleted. - The remaining three must be changed so that mymachine replaces - crownbay-noemgd and crownbay. - Here is the final linux-yocto-2.6.37.bbappend file after all - the edits: - - FILESEXTRAPATHS_prepend := "${THISDIR}/${PN}:" - - COMPATIBLE_MACHINE_mymachine = "mymachine" - KMACHINE_mymachine = "yocto/standard/mymachine" - KERNEL_FEATURES_append_mymachine += " cfg/smp.scc" - - SRCREV_machine_pn-linux-yocto_mymachine ?= \ - "fce17f046d3756045e4dfb49221d1cf60fcae329" - SRCREV_meta_pn-linux-yocto_mymachine ?= \ - "84f1a422d7e21fbc23a687035bdf9d42471f19e0" - - - - - In summary, the edits to the layer’s recipe files result in removal of any files and - statements that do not support your targeted hardware in addition to the inclusion - of any new recipes you might need. - In this example, it was simply a matter of ridding the new layer - meta-machine of any code that supported the EMGD features - and making sure we were identifying the kernel that supports our example, which - is the atom-pc-standard kernel. - We did not introduce any new recipes to the layer. - - - - Finally, it is also important to update the layer’s README - file so that the information in it reflects your BSP. - -
- -
- Preparing for the Build - - - Once you have made all the changes to your BSP layer there remains a few things - you need to do for the Yocto Project build system in order for it to create your image. - You need to get the build environment ready by sourcing an environment setup script - and you need to be sure two key configuration files are configured appropriately. - - - - The entire process for building an image is overviewed in the - - Building an Image section of the Yocto Project Quick Start. - You might want to reference this information. - The remainder of this section will apply to our example of the - meta-mymachine layer. - - - - To get ready to build your image that uses the new layer you need to do the following: - - Get the environment ready for the build by sourcing the environment - script. - The environment script is in the top-level of the local Yocto Project files - directory structure. - The script has the string - init-build-env in the file’s name. - For this example, the following command gets the build environment ready: - - $ source oe-init-build-env yocto-build - - When you source the script a build directory is created in the current - working directory. - In our example we were in the poky directory. - Thus, entering the previous command created the yocto-build directory. - If you do not provide a name for the build directory it defaults to - build. - The yocot-build directory contains a - conf directory that has - two configuration files you will need to check: bblayers.conf - and local.conf. - Check and edit the resulting local.conf file. - This file minimally identifies the machine for which to build the image by - configuring the MACHINE variable. - For this example you must set the variable to mymachine as follows: - - MACHINE ??= “mymachine” - - You should also be sure any other variables in which you are interested are set. - Some variables to consider are BB_NUMBER_THREADS - and PARALLEL_MAKE, both of which can greatly reduce your build time - if you are using a multi-threaded development system (e.g. values of - 8 and j 6, respectively are optimal - for a development machine that has four available cores). - Update the bblayers.conf file so that it includes - the path to your new BSP layer. - In this example you need to include the pathname to meta-mymachine. - For this example the - BBLAYERS variable in the file would need to include the following path: - - $HOME/poky/meta-intel/meta-mymachine - - - - - - The appendix - - Reference: Variables Glossary in the Yocto Project Reference Manual has more information - on configuration variables. - -
- -
- Building the Image - - - The Yocto Project uses the BitBake tool to build images based on the type of image - you want to create. - You can find more information on BitBake - here. - - - - The build process supports several types of images to satisfy different needs. - When you issue the BitBake command you provide a “top-level” recipe that essentially - starts the process off of building the type of image you want. - - - - [WRITER'S NOTE: Consider moving this to the Poky Reference Manual.] - - - - You can find these recipes in the meta/recipes-core/images and - meta/recipes-sato/images directories of your local Yocto Project - file structure (Git repository or extracted release tarball). - Although the recipe names are somewhat explanatory, here is a list that describes them: - - Base – A foundational basic image without support - for X that can be reasonably used for customization. - Core – A foundational basic image with support for - X that can be reasonably used for customization. - Direct Disk – An image that you can copy directory to - the disk of the target device. - Live – An image you can run from a USB device or from - a CD without having to first install something. - Minimal – A small image without a GUI. - This image is not much more than a kernel with a shell. - Minimal Development – A Minimal image suitable for - development work. - Minimal Direct Disk – A Minimal Direct Disk image. - Minimal RAM-based Initial Root Filesystem – A minimal image - that has the initramfs as part of the kernel, which allows the - system to find the first “init” program more efficiently. - Minimal Live – A Minimal Live image. - Minimal MTD Utilities – A minimal image that has support - for the MTD utilities, which let the user interact with the MTD subsystem in - the kernel to perform operations on flash devices. - Sato – An image with Sato support, a mobile environment - and visual style that works well with mobile devices. - Sato Development – A Sato image suitable for - development work. - Sato Direct Disk – A Sato Direct Disk image. - Sato Live – A Sato Live image. - Sato SDK – A Sato image that includes the Yocto Project - toolchain and development libraries. - Sato SDK Direct Disk – A Sato SDK Direct - Disk image. - Sato SDK Live – A Sato SDK Live image. - - - - - The remainder of this section applies to our example of the meta-mymachine layer. - - - - To build the image for our meta-mymachine BSP enter the following command - from the same shell from which you ran the setup script. - You should run the bitbake command without any intervening shell commands. - For example, moving your working directory around could cause problems. - Here is the command for this example: - - $ bitbake –k core-image-sato-live - - - - - This command specifies an image that has Sato support and that can be run from a USB device or - from a CD without having to first install anything. - The build process takes significant time and includes thousands of tasks, which are reported - at the console. - If the build results in any type of error you should check for misspellings in the - files you changed or problems with your host development environment such as missing packages. - -
+ + You can view a video presentation of the BSP creation process + here. + You can also find supplemental information in the + + Board Support Package (BSP) Development Guide. + Finally, there is wiki page write up of the example located + + here you might find helpful. +
@@ -883,9 +351,9 @@ You need to have the Yocto Project files available on your host system. - The process is identical to that described in getting the files in section - "Setting Up Yocto Project" for - the BSP development case. + The process is identical to that described in the + "Getting Setup" section earlier in this + manual. Be sure to either set up a local Git repository for poky or download and unpack the Yocto Project release tarball. -- cgit v1.2.3-54-g00ecf