diff options
author | Scott Rifenbark <srifenbark@gmail.com> | 2016-03-21 14:25:47 -0700 |
---|---|---|
committer | Richard Purdie <richard.purdie@linuxfoundation.org> | 2016-03-23 21:56:09 +0000 |
commit | 7233e359ddc50c80415c746449c33aa0fe83862d (patch) | |
tree | 66c18581190b4fa64f93be2e918a62ba81e2d8d7 /documentation/sdk-manual | |
parent | b31bf7c68b99d5893ab671612cda34ce01a631bf (diff) | |
download | openembedded-core-contrib-7233e359ddc50c80415c746449c33aa0fe83862d.tar.gz |
sdk-manual: Edits to add extensible SDK configuration sections.
(From yocto-docs rev: 378bbceb8ea06c225c4758807e25a35521faa3a9)
Signed-off-by: Scott Rifenbark <srifenbark@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Diffstat (limited to 'documentation/sdk-manual')
-rw-r--r-- | documentation/sdk-manual/sdk-appendix-customizing.xml | 381 | ||||
-rw-r--r-- | documentation/sdk-manual/sdk-appendix-obtain.xml | 82 | ||||
-rw-r--r-- | documentation/sdk-manual/sdk-extensible.xml | 116 | ||||
-rw-r--r-- | documentation/sdk-manual/sdk-intro.xml | 28 |
4 files changed, 506 insertions, 101 deletions
diff --git a/documentation/sdk-manual/sdk-appendix-customizing.xml b/documentation/sdk-manual/sdk-appendix-customizing.xml index 2068143df3..3ee0d7c90a 100644 --- a/documentation/sdk-manual/sdk-appendix-customizing.xml +++ b/documentation/sdk-manual/sdk-appendix-customizing.xml @@ -6,17 +6,380 @@ <title>Customizing the SDK</title> -<para role='writernotes'> - This chapter is going to cover the details on extending the SDK through - user customizations. - I am not sure if this is possible for both the standard and extensible - SDK or what. +<para> + This appendix presents customizations you can apply to both the standard + and extensible SDK. + Each subsection identifies the type of SDK to which the section applies. </para> -<para role='writernotes'> - I do not have a feel for what sub-topics need to be covered here. - I need to get this information from Paul. -</para> +<section id='sdk-configuring-the-extensible-sdk'> + <title>Configuring the Extensible SDK</title> + + <para> + The extensible SDK primarily consists of a pre-configured copy of + the build system from which it was produced. + Thus, the SDK's configuration is derived using that build system. + However, filters exist that are applied such as the following that + are applied to <filename>local.conf</filename> and + <filename>auto.conf</filename> when present: + <itemizedlist> + <listitem><para> + Variables whose values start with "/" are excluded since the + assumption is that those values are paths that are likely to + be specific to the build host. + </para></listitem> + <listitem><para> + Variables listed in + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_LOCAL_CONF_BLACKLIST'><filename>SDK_LOCAL_CONF_BLACKLIST</filename></ulink> + are excluded. + The default value blacklists + <ulink url='&YOCTO_DOCS_REF_URL;#var-CONF_VERSION'><filename>CONF_VERSION</filename></ulink>, + <ulink url='&YOCTO_DOCS_REF_URL;#var-BB_NUMBER_THREADS'><filename>BB_NUMBER_THREADS</filename></ulink>, + <ulink url='&YOCTO_DOCS_REF_URL;#var-PARALLEL_MAKE'><filename>PARALLEL_MAKE</filename></ulink>, + <ulink url='&YOCTO_DOCS_REF_URL;#var-PRSERV_HOST'><filename>PRSERV_HOST</filename></ulink>, + and + <ulink url='&YOCTO_DOCS_REF_URL;#var-SSTATE_MIRRORS'><filename>SSTATE_MIRRORS</filename></ulink>. + </para></listitem> + <listitem><para> + Variables listed in + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_LOCAL_CONF_WHITELIST'><filename>SDK_LOCAL_CONF_WHITELIST</filename></ulink> + are included. + Including these variables overrides either of the above two + conditions. + The default value is blank. + </para></listitem> + <listitem><para> + Classes inherited globally with + <ulink url='&YOCTO_DOCS_REF_URL;#var-INHERIT'><filename>INHERIT</filename></ulink> + that are listed in + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_INHERIT_BLACKLIST'><filename>SDK_INHERIT_BLACKLIST</filename></ulink> + are disabled. + Using <filename>SDK_INHERIT_BLACKLIST</filename> to disable + these classes is is the typical method to disable classes that + are problematic or unnecessary in the SDK context. + The default value blacklists the + <ulink url='&YOCTO_DOCS_REF_URL;#ref-classes-buildhistory'><filename>buildhistory</filename></ulink> + and + <ulink url='&YOCTO_DOCS_REF_URL;#ref-classes-icecc'><filename>icecc</filename></ulink> + classes. + </para></listitem> + </itemizedlist> + Additionally, the contents of <filename>conf/sdk-extra.conf</filename>, + when present, are appended to the end of + <filename>conf/local.conf</filename> within the produced SDK, without + any filtering. + Not filtering these contents is particularly useful if you want to + set a variable value just for the SDK and not the build system used to + create the SDK. + </para> +</section> + +<section id='adjusting-the-extensible-sdk-to-suit-your-build-system-setup'> + <title>Adjusting the Extensible SDK to Suit Your Build System Setup</title> + + <para> + In most cases, the extensible SDK defaults should work. + However, some cases exist for which you might consider making + adjustments: + <itemizedlist> + <listitem><para> + If your SDK configuration inherits additional classes + using the + <ulink url='&YOCTO_DOCS_REF_URL;#var-INHERIT'><filename>INHERIT</filename></ulink> + variable and you do not need or want those classes enabled in + the SDK, you can blacklist them by adding them to the + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_INHERIT_BLACKLIST'><filename>SDK_INHERIT_BLACKLIST</filename></ulink> + variable. + The default value of <filename>SDK_INHERIT_BLACKLIST</filename> + is set using the "?=" operator. + Consequently, you will need to either set the complete value + using "=" or append the value using "_append". + </para></listitem> + <listitem><para> + If you have classes or recipes that add additional tasks to + the standard build flow (i.e. that execute as part of building + the recipe as opposed to needing to be called explicitly), then + you need to do one of the following: + <itemizedlist> + <listitem><para> + Ensure the tasks are shared state tasks (i.e. their + output is saved to and can be restored from the shared + state cache), or that the tasks are able to be + produced quickly from a task that is a shared state + task and add the task name to the value of + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_RECRDEP_TASKS'><filename>SDK_RECRDEP_TASKS</filename></ulink>. + </para></listitem> + <listitem><para> + Disable the tasks if they are added by a class and + you do not need the functionality the class provides + in the extensible SDK. + To disable the tasks, add the class to + <filename>SDK_INHERIT_BLACKLIST</filename> as previously + described. + </para></listitem> + </itemizedlist> + </para></listitem> + <listitem><para> + Generally, you want to have a shared state mirror set up so + users of the SDK can add additional items to the SDK after + installation without needing to build the items from source. + See the + "<link linkend='sdk-providing-additional-installable-extensible-sdk-content'>Providing Additional Installable Extensible SDK Content</link>" + section for information. + </para></listitem> + <listitem><para> + If you want users of the SDK to be able to easily update the + SDK, you need to set the + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_UPDATE_URL'><filename>SDK_UPDATE_URL</filename></ulink> + variable. + For more information, see the + "<link linkend='sdk-providing-updates-after-installing-the-extensible-sdk'>Providing Updates After Installing the Extensible SDK</link>" + section. + </para></listitem> + <listitem><para> + If you have adjusted the list of files and directories that + appear in + <ulink url='&YOCTO_DOCS_REF_URL;#var-COREBASE'><filename>COREBASE</filename></ulink> + (other than layers that are enabled through + <filename>bblayers.conf</filename>), then must list these + files in + <ulink url='&YOCTO_DOCS_REF_URL;#var-COREBASE_FILES'><filename>COREBASE_FILES</filename></ulink> + so that the files are copied into the SDK. + </para></listitem> + <listitem><para> + If your build system setup uses a different environment setup + script other than + <ulink url='&YOCTO_DOCS_REF_URL;#structure-core-script'><filename>&OE_INIT_FILE;</filename></ulink> + or + <ulink url='&YOCTO_DOCS_REF_URL;#structure-memres-core-script'><filename>oe-init-build-env-memres</filename></ulink>, + then you must set + <ulink url='&YOCTO_DOCS_REF_URL;#var-OE_INIT_ENV_SCRIPT'><filename>OE_INIT_ENV_SCRIPT</filename></ulink> + to point to the environment setup script you use. + <note> + You must also reflect this change in the value used for the + <filename>COREBASE_FILES</filename> variable as previously + described. + </note> + </para></listitem> + </itemizedlist> + </para> +</section> + +<section id='sdk-changing-the-appearance-of-the-extensible-sdk'> + <title>Changing the Appearance of the Extensible SDK</title> + + <para> + You can change the title shown by the SDK installer by setting the + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_TITLE'><filename>SDK_TITLE</filename></ulink> + variable. + By default, this title is derived from + <ulink url='&YOCTO_DOCS_REF_URL;#var-DISTRO_NAME'><filename>DISTRO_NAME</filename></ulink> + when it is set. + If the <filename>DISTRO_NAME</filename> variable is not set, the title + is derived from the + <ulink url='&YOCTO_DOCS_REF_URL;#var-DISTRO'><filename>DISTRO</filename></ulink> + variable. + </para> +</section> + +<section id='sdk-providing-updates-after-installing-the-extensible-sdk'> + <title>Providing Updates After Installing the Extensible SDK</title> + + <para> + When you make changes to your configuration or to the metadata and + if you want those changes to be reflected in installed SDKs, you need + to perform additional steps to make it possible for those that use + the SDK to update their installations with the + <filename>devtool sdk-update</filename> command: + <orderedlist> + <listitem><para> + Arrange to be created a directory that can be shared over + HTTP or HTTPS. + </para></listitem> + <listitem><para> + Set the + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_UPDATE_URL'><filename>SDK_UPDATE_URL</filename></ulink> + variable to point to the corresponding HTTP or HTTPS URL. + Setting this variable causes any SDK built to default to that + URL and thus, the user does not have to pass the URL to the + <filename>devtool sdk-update</filename> command. + </para></listitem> + <listitem><para> + Build the extensible SDK normally (i.e., use the + <filename>bitbake -c populate_sdk_ext</filename> <replaceable>imagename</replaceable> + command). + </para></listitem> + <listitem><para> + Publish the SDK using the following command: + <literallayout class='monospaced'> + $ oe-publish-sdk <replaceable>some_path</replaceable>/sdk-installer.sh <replaceable>path_to_shared/http_directory</replaceable> + </literallayout> + You must repeat this step each time you rebuild the SDK + with changes that you want to make available through the + update mechanism. + </para></listitem> + </orderedlist> + </para> + + <para> + Completing the above steps allows users of the existing SDKs to + simply run <filename>devtool sdk-update</filename> to retrieve the + latest updates. + See the + "<link linkend='sdk-updating-the-extensible-sdk'>Updating the Extensible SDK</link>" + section for further information. + </para> +</section> + +<section id='sdk-providing-additional-installable-extensible-sdk-content'> + <title>Providing Additional Installable Extensible SDK Content</title> + + <para> + If you want the users of the extensible SDK you are building to be + able to add items to the SDK without needing to build the + items from source, you need to do a number of things: + <orderedlist> + <listitem><para> + Ensure the additional items you want the user to be able to + install are actually built. + You can ensure these items are built a number of different + ways: 1) Build them explicitly, perhaps using one or more + "meta" recipes that depend on lists of other recipes to keep + things tidy, or 2) Build the "world" target and set + <filename>EXCLUDE_FROM_WORLD_pn-</filename><replaceable>recipename</replaceable> + for the recipes you do not want built. + See the + <ulink url='&YOCTO_DOCS_REF_URL;#var-EXCLUDE_FROM_WORLD'><filename>EXCLUDE_FROM_WORLD</filename></ulink> + variable for additional information. + </para></listitem> + <listitem><para> + Expose the <filename>sstate-cache</filename> directory + produced by the build. + Typically, you expose this directory over HTTP or HTTPS. + </para></listitem> + <listitem><para> + Set the appropriate configuration so that the produced SDK + knows how to find the configuration. + The variable you need to set is + <ulink url='&YOCTO_DOCS_REF_URL;#var-SSTATE_MIRRORS'><filename>SSTATE_MIRRORS</filename></ulink>: + <literallayout class='monospaced'> + SSTATE_MIRRORS = "file://.* http://<replaceable>example</replaceable>.com/<replaceable>some_path</replaceable>/sstate-cache/PATH" + </literallayout> + You can set the <filename>SSTATE_MIRRORS</filename> variable + in two different places: + <itemizedlist> + <listitem><para> + If the mirror value you are setting is appropriate to + be set for both the build system that is actually + building the SDK and the SDK itself (i.e. the mirror + is accessible in both places or it will fail quickly + on the build system side, and its contents will not + interfere with the build), then you can set the + variable in your <filename>local.conf</filename> + or custom distro configuration file. + You can "whitelist" the variable through the SDK by + adding the following: + <literallayout class='monospaced'> + SDK_LOCAL_CONF_WHITELIST = "SSTATE_MIRRORS" + </literallayout> + </para></listitem> + <listitem><para> + Alternatively, if you just want to set the + <filename>SSTATE_MIRRORS</filename> variable's value + for the SDK alone, create a + <filename>conf/sdk-extra.conf</filename> either in + your + <ulink url='&YOCTO_DOCS_DEV_URL;#build-directory'>Build Directory</ulink> + or within any layer and put your + <filename>SSTATE_MIRRORS</filename> setting within + that file. + <note> + This second option is the safest option should + you have any doubts as to which method to use when + setting <filename>SSTATE_MIRRORS</filename>. + </note> + </para></listitem> + </itemizedlist> + </para></listitem> + </orderedlist> + </para> +</section> + +<section id='sdk-minimizing-the-size-of-the-extensible-sdk-installer-download'> + <title>Minimizing the Size of the Extensible SDK Installer Download</title> + + <para> + By default, the extensible SDK bundles the shared state artifacts for + everything needed to reconstruct the image for which the SDK was built. + This bundling can lead to an SDK installer file that is a Gigabyte or + more in size. + If the size of this file causes a problem, you can build an SDK that + has just enough in it to install and provide access to the + <filename>devtool command</filename> by setting the following in your + configuration: + <literallayout class='monospaced'> + SDK_EXT_TYPE = "minimal" + </literallayout> + Setting + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_EXT_TYPE'><filename>SDK_EXT_TYPE</filename></ulink> + to "minimal" produces an SDK installer that is around 35 Mbytes in + size, which downloads and installs quickly. + You need to realize, though, that the installer does not install any + libraries or tools out of the box. + These must be installed either "on the fly" or through actions you + perform using <filename>devtool</filename> or explicitly with the + <filename>devtool sdk-install</filename> command. + </para> + + <para> + In most cases, when building a minimal SDK you will need to also enable + bringing in the information on a wider range of packages produced by + the system. + This is particularly true so that <filename>devtool add</filename> + is able to effectively map dependencies it discovers in a source tree + to the appropriate recipes. + Also so that the <filename>devtool search</filename> command + is able to return useful results. + </para> + + <para> + To facilitate this wider range of information, you would additionally + set the following: + <literallayout class='monospaced'> + SDK_INCLUDE_PKGDATA = "1" + </literallayout> + See the + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_INCLUDE_PKGDATA'><filename>SDK_INCLUDE_PKGDATA</filename></ulink> + variable for additional information. + </para> + + <para> + Setting the <filename>SDK_INCLUDE_PKGDATA</filename> variable as + shown causes the "world" target to be built so that information + for all of the recipes included within it are available. + Having these recipes available increases build time significantly and + increases the size of the SDK installer by 30-80 Mbytes depending on + how many recipes are included in your configuration. + </para> + + <para> + You can use + <filename>EXCLUDE_FROM_WORLD_pn-</filename><replaceable>recipename</replaceable> + for recipes you want to exclude. + However, it is assumed that you would need to be building the "world" + target if you want to provide additional items to the SDK. + Consequently, building for "world" should not represent undue + overhead in most cases. + <note> + If you set <filename>SDK_EXT_TYPE</filename> to "minimal", + then providing a shared state mirror is mandatory so that items + can be installed as needed. + See the + "<link linkend='sdk-providing-additional-installable-extensible-sdk-content'>Providing Additional Installable Extensible SDK Content</link>" + section for more information. + </note> + </para> +</section> </appendix> <!-- diff --git a/documentation/sdk-manual/sdk-appendix-obtain.xml b/documentation/sdk-manual/sdk-appendix-obtain.xml index 6ffc958695..daa5e79fe8 100644 --- a/documentation/sdk-manual/sdk-appendix-obtain.xml +++ b/documentation/sdk-manual/sdk-appendix-obtain.xml @@ -52,18 +52,20 @@ <para> As an alternative to locating and downloading a toolchain installer, - you can build the toolchain installer if you have a - <ulink url='&YOCTO_DOCS_DEV_URL;#build-directory'>Build Directory</ulink>. - <note> - Although not the preferred method, it is also possible to use - <filename>bitbake meta-toolchain</filename> to build the toolchain - installer. - If you do use this method, you must separately install and extract - the target sysroot. - For information on how to install the sysroot, see the - "<link linkend='sdk-extracting-the-root-filesystem'>Extracting the Root Filesystem</link>" - section. - </note> + you can build the toolchain installer assuming you have first sourced + the environment setup script. + See the + "<ulink url='&YOCTO_DOCS_QS_URL;#qs-building-images'>Building Images</ulink>" + section in the Yocto Project Quick Start for steps that show you + how to set up the Yocto Project environment. + In particular, you need to be sure the + <ulink url='&YOCTO_DOCS_REF_URL;#var-MACHINE'><filename>MACHINE</filename></ulink> + variable matches the architecture for which you are building and that + the + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDKMACHINE'><filename>SDKMACHINE</filename></ulink> + variable is correctly set if you are building a toolchain designed to + run on an architecture that differs from your current development host + machine (i.e. the build machine). </para> <para> @@ -81,54 +83,6 @@ </para> <para> - Another powerful feature is that the toolchain is completely - self-contained. - The binaries are linked against their own copy of - <filename>libc</filename>, which results in no dependencies - on the target system. - To achieve this, the pointer to the dynamic loader is - configured at install time since that path cannot be dynamically - altered. - This is the reason for a wrapper around the - <filename>populate_sdk</filename> and - <filename>populate_sdk_ext</filename> archives. - </para> - - <para> - Another feature is that only one set of cross-canadian toolchain - binaries are produced per architecture. - This feature takes advantage of the fact that the target hardware can - be passed to <filename>gcc</filename> as a set of compiler options. - Those options are set up by the environment script and contained in - variables such as - <ulink url='&YOCTO_DOCS_REF_URL;#var-CC'><filename>CC</filename></ulink> - and - <ulink url='&YOCTO_DOCS_REF_URL;#var-LD'><filename>LD</filename></ulink>. - This reduces the space needed for the tools. - Understand, however, that a sysroot is still needed for every target - since those binaries are target-specific. - </para> - - <para> - Remember, before using any BitBake command, you - must source the build environment setup script - (i.e. - <ulink url='&YOCTO_DOCS_REF_URL;#structure-core-script'><filename>&OE_INIT_FILE;</filename></ulink> - or - <ulink url='&YOCTO_DOCS_REF_URL;#structure-memres-core-script'><filename>oe-init-build-env-memres</filename></ulink>) - located in the Source Directory and you must make sure your - <filename>conf/local.conf</filename> variables are correct. - In particular, you need to be sure the - <ulink url='&YOCTO_DOCS_REF_URL;#var-MACHINE'><filename>MACHINE</filename></ulink> - variable matches the architecture for which you are building and that - the - <ulink url='&YOCTO_DOCS_REF_URL;#var-SDKMACHINE'><filename>SDKMACHINE</filename></ulink> - variable is correctly set if you are building a toolchain designed to - run on an architecture that differs from your current development host - machine (i.e. the build machine). - </para> - - <para> When the <filename>bitbake</filename> command completes, the toolchain installer will be in <filename>tmp/deploy/sdk</filename> in the Build Directory. @@ -154,12 +108,8 @@ <title>Extracting the Root Filesystem</title> <para> - After installing the toolchain or building it using BitBake, - you need a root filesystem, which you need to separately extract. - </para> - - <para> - Here are some cases where you need to extract the root filesystem: + After installing the toolchain, for some use cases you + might need to separately extract a root filesystem: <itemizedlist> <listitem><para>You want to boot the image using NFS. </para></listitem> diff --git a/documentation/sdk-manual/sdk-extensible.xml b/documentation/sdk-manual/sdk-extensible.xml index bc9ccd28d3..f9f04072d7 100644 --- a/documentation/sdk-manual/sdk-extensible.xml +++ b/documentation/sdk-manual/sdk-extensible.xml @@ -540,39 +540,103 @@ </para> </section> -<section id='sdk-using-the-extensible-sdk-to-task-2'> - <title>Using the Extensible SDK to <replaceable>item-2</replaceable></title> - - <para role='writernotes'> - Describe the specific task you are going to accomplish with the - extensible SDK. - Provide a diagram showing the rough flow of the task. - Provide specific steps using a real example that works through the - task. +<section id='sdk-installing-additional-items-into-the-extensible-sdk'> + <title>Installing Additional Items Into the Extensible SDK</title> + + <para> + The extensible SDK typically only comes with a small number of tools + and libraries out of the box. + If you have a minimal SDK, then it starts mostly empty and is + populated on-demand. + However, sometimes you will need to explicitly install extra items + into the SDK. + If you need these extra items, you can first search for the items + using the <filename>devtool search</filename> command. + For example, suppose you need to link to libGL but you are not sure + which recipe provides it. + You can use the following command to find out: + <literallayout class='monospaced'> + $ devtool search libGL + mesa A free implementation of the OpenGL API + </literallayout> + Once you know the recipe (i.e. <filename>mesa</filename> in this + example), you can install it: + <literallayout class='monospaced'> + $ devtool sdk-install mesa + </literallayout> + By default, the <filename>devtool sdk-install</filename> assumes the + item is available in pre-built form from your SDK provider. + If the item is not available and it is acceptable to build the item + from source, you can add the "-s" option as follows: + <literallayout class='monospaced'> + $ devtool sdk-install -s mesa + </literallayout> + It is important to remember that building the item from source takes + significantly longer than installing the pre-built artifact. + Also, if no recipe exists for the item you want to add to the SDK, you + must add it using the <filename>devtool add</filename> command. </para> </section> -<section id='sdk-using-the-extensible-sdk-to-task-3'> - <title>Using the Extensible SDK to <replaceable>item-3</replaceable></title> - - <para role='writernotes'> - Describe the specific task you are going to accomplish with the - extensible SDK. - Provide a diagram showing the rough flow of the task. - Provide specific steps using a real example that works through the - task. +<section id='sdk-updating-the-extensible-sdk'> + <title>Updating the Extensible SDK</title> + + <para> + If you are working with an extensible SDK that gets occasionally + updated (e.g. typically when that SDK has been provided to you by + another party), then you will need to manually pull down those + updates to your installed SDK. + </para> + + <para> + To update your installed SDK, run the following: + <literallayout class='monospaced'> + $ devtool sdk-update + </literallayout> + The previous command assumes your SDK provider has set the default + update URL for you. + If that URL has not been set, you need to specify it yourself as + follows: + <literallayout class='monospaced'> + $ devtool sdk-update <replaceable>path_to_update_directory</replaceable> + </literallayout> + <note> + The URL needs to point specifically to a published SDK and not an + SDK installer that you would download and install. + </note> </para> </section> -<section id='sdk-using-the-extensible-sdk-to-task-x'> - <title>Using the Extensible SDK to <replaceable>item-x</replaceable></title> +<section id='sdk-creating-a-derivative-sdk-with-additional-components'> + <title>Creating a Derivative SDK With Additional Components</title> - <para role='writernotes'> - Describe the specific task you are going to accomplish with the - extensible SDK. - Provide a diagram showing the rough flow of the task. - Provide specific steps using a real example that works through the - task. + <para> + You might need to produce an SDK that contains your own custom + libraries for sending to a third party (e.g., if you are a vendor with + customers needing to build their own software for the target platform). + If that is the case, then you can produce a derivative SDK based on + the currently installed SDK fairly easily. + Use these steps: + <orderedlist> + <listitem><para>If necessary, install an extensible SDK that + you want to use as a base for your derivative SDK. + </para></listitem> + <listitem><para>Source the environment script for the SDK. + </para></listitem> + <listitem><para>Add the extra libraries or other components + you want by using the <filename>devtool add</filename> + command. + </para></listitem> + <listitem><para>Run the <filename>devtool build-sdk</filename> + command. + </para></listitem> + </orderedlist> + The above procedure takes the recipes added to the workspace and + constructs a new SDK installer containing those recipes and the + resulting binary artifacts. + The recipes go into their own separate layer in the constructed + derivative SDK, leaving the workspace clean and ready for you + to add your own recipes. </para> </section> diff --git a/documentation/sdk-manual/sdk-intro.xml b/documentation/sdk-manual/sdk-intro.xml index 36d946459d..d71aafeba1 100644 --- a/documentation/sdk-manual/sdk-intro.xml +++ b/documentation/sdk-manual/sdk-intro.xml @@ -46,6 +46,34 @@ </para> <para> + SDKs are completely self-contained. + The binaries are linked against their own copy of + <filename>libc</filename>, which results in no dependencies + on the target system. + To achieve this, the pointer to the dynamic loader is + configured at install time since that path cannot be dynamically + altered. + This is the reason for a wrapper around the + <filename>populate_sdk</filename> and + <filename>populate_sdk_ext</filename> archives. + </para> + + <para> + Another feature for the SDKs is that only one set of cross-canadian + toolchain binaries are produced per architecture. + This feature takes advantage of the fact that the target hardware can + be passed to <filename>gcc</filename> as a set of compiler options. + Those options are set up by the environment script and contained in + variables such as + <ulink url='&YOCTO_DOCS_REF_URL;#var-CC'><filename>CC</filename></ulink> + and + <ulink url='&YOCTO_DOCS_REF_URL;#var-LD'><filename>LD</filename></ulink>. + This reduces the space needed for the tools. + Understand, however, that a sysroot is still needed for every target + since those binaries are target-specific. + </para> + + <para> Going beyond the actual SDK, the SDK development environment consists of the following: <itemizedlist> |