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diff --git a/documentation/sdk-manual/sdk-intro.xml b/documentation/sdk-manual/sdk-intro.xml deleted file mode 100644 index f42670ea6e..0000000000 --- a/documentation/sdk-manual/sdk-intro.xml +++ /dev/null @@ -1,353 +0,0 @@ -<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" -"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd" -[<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] > -<!--SPDX-License-Identifier: CC-BY-2.0-UK--> - -<chapter id='sdk-intro'> -<title>Introduction</title> - -<section id='sdk-manual-intro'> - <title>Introduction</title> - - <para> - Welcome to the Yocto Project Application Development and the - Extensible Software Development Kit (eSDK) manual. - This manual provides information that explains how to use both the - Yocto Project extensible and standard SDKs to develop - applications and images. - <note> - Prior to the 2.0 Release of the Yocto Project, application - development was primarily accomplished through the use of the - Application Development Toolkit (ADT) and the availability - of stand-alone cross-development toolchains and other tools. - With the 2.1 Release of the Yocto Project, application development - has transitioned to within a tool-rich extensible SDK and the more - traditional standard SDK. - </note> - </para> - - <para> - All SDKs consist of the following: - <itemizedlist> - <listitem><para> - <emphasis>Cross-Development Toolchain</emphasis>: - This toolchain contains a compiler, debugger, and various - miscellaneous tools. - </para></listitem> - <listitem><para> - <emphasis>Libraries, Headers, and Symbols</emphasis>: - The libraries, headers, and symbols are specific to the image - (i.e. they match the image). - </para></listitem> - <listitem><para> - <emphasis>Environment Setup Script</emphasis>: - This <filename>*.sh</filename> file, once run, sets up the - cross-development environment by defining variables and - preparing for SDK use. - </para></listitem> - </itemizedlist> - </para> - - <para> - Additionally, an extensible SDK has tools that allow you to easily add - new applications and libraries to an image, modify the source of an - existing component, test changes on the target hardware, and easily - integrate an application into the - <ulink url='&YOCTO_DOCS_REF_URL;#build-system-term'>OpenEmbedded build system</ulink>. - </para> - - <para> - You can use an SDK to independently develop and test code - that is destined to run on some target machine. - 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-compiler - toolchain binaries are produced for any given 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 every target still needs a sysroot because - those binaries are target-specific. - </para> - - <para> - The SDK development environment consists of the following: - <itemizedlist> - <listitem><para> - The self-contained SDK, which is an - architecture-specific cross-toolchain and - matching sysroots (target and native) all built by the - OpenEmbedded build system (e.g. the SDK). - The toolchain and sysroots are based on a - <ulink url='&YOCTO_DOCS_REF_URL;#metadata'>Metadata</ulink> - configuration and extensions, - which allows you to cross-develop on the host machine for the - target hardware. - Additionally, the extensible SDK contains the - <filename>devtool</filename> functionality. - </para></listitem> - <listitem><para> - The Quick EMUlator (QEMU), which lets you simulate - target hardware. - QEMU is not literally part of the SDK. - You must build and include this emulator separately. - However, QEMU plays an important role in the development - process that revolves around use of the SDK. - </para></listitem> - </itemizedlist> - </para> - - <para> - In summary, the extensible and standard SDK share many features. - However, the extensible SDK has powerful development tools to help you - more quickly develop applications. - Following is a table that summarizes the primary differences between - the standard and extensible SDK types when considering which to - build: - <informaltable frame='none'> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1' colwidth='1*'/> - <colspec colname='c2' colwidth='1*'/> - <colspec colname='c3' colwidth='1*'/> - <thead> - <row> - <entry align="left"><emphasis>Feature</emphasis></entry> - <entry align="left"><emphasis>Standard SDK</emphasis></entry> - <entry align="left"><emphasis>Extensible SDK</emphasis></entry> - </row> - </thead> - <tbody> - <row> - <entry align="left">Toolchain</entry> - <entry align="left">Yes</entry> - <entry align="left">Yes*</entry> - </row> - <row> - <entry align="left">Debugger</entry> - <entry align="left">Yes</entry> - <entry align="left">Yes*</entry> - </row> - <row> - <entry align="left">Size</entry> - <entry align="left">100+ MBytes</entry> - <entry align="left">1+ GBytes (or 300+ MBytes for minimal w/toolchain)</entry> - </row> - <row> - <entry align="left"><filename>devtool</filename></entry> - <entry align="left">No</entry> - <entry align="left">Yes</entry> - </row> - <row> - <entry align="left">Build Images</entry> - <entry align="left">No</entry> - <entry align="left">Yes</entry> - </row> - <row> - <entry align="left">Updateable</entry> - <entry align="left">No</entry> - <entry align="left">Yes</entry> - </row> - <row> - <entry align="left">Managed Sysroot**</entry> - <entry align="left">No</entry> - <entry align="left">Yes</entry> - </row> - <row> - <entry align="left">Installed Packages</entry> - <entry align="left">No***</entry> - <entry align="left">Yes****</entry> - </row> - <row> - <entry align="left">Construction</entry> - <entry align="left">Packages</entry> - <entry align="left">Shared State</entry> - </row> - </tbody> - </tgroup> - </informaltable> - <literallayout class='monospaced'> - * Extensible SDK contains the toolchain and debugger if <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_EXT_TYPE'><filename>SDK_EXT_TYPE</filename></ulink> is "full" or <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_INCLUDE_TOOLCHAIN'><filename>SDK_INCLUDE_TOOLCHAIN</filename></ulink> is "1", which is the default. - - ** Sysroot is managed through the use of <filename>devtool</filename>. Thus, it is less likely that you will corrupt your SDK sysroot when you try to add additional libraries. - - *** You can add runtime package management to the standard SDK but it is not supported by default. - - **** You must build and make the shared state available to extensible SDK users for "packages" you want to enable users to install. - </literallayout> - </para> - - <section id='the-cross-development-toolchain'> - <title>The Cross-Development Toolchain</title> - - <para> - The - <ulink url='&YOCTO_DOCS_REF_URL;#cross-development-toolchain'>Cross-Development Toolchain</ulink> - consists of a cross-compiler, cross-linker, and cross-debugger - that are used to develop user-space applications for targeted - hardware. - Additionally, for an extensible SDK, the toolchain also has - built-in <filename>devtool</filename> functionality. - This toolchain is created by running a SDK installer script - or through a - <ulink url='&YOCTO_DOCS_REF_URL;#build-directory'>Build Directory</ulink> - that is based on your metadata configuration or extension for - your targeted device. - The cross-toolchain works with a matching target sysroot. - </para> - </section> - - <section id='sysroot'> - <title>Sysroots</title> - - <para> - The native and target sysroots contain needed headers and libraries - for generating binaries that run on the target architecture. - The target sysroot is based on the target root filesystem image - that is built by the OpenEmbedded build system and uses the same - metadata configuration used to build the cross-toolchain. - </para> - </section> - - <section id='the-qemu-emulator'> - <title>The QEMU Emulator</title> - - <para> - The QEMU emulator allows you to simulate your hardware while - running your application or image. - QEMU is not part of the SDK but is made available a number of - different ways: - <itemizedlist> - <listitem><para> - If you have cloned the <filename>poky</filename> Git - repository to create a - <ulink url='&YOCTO_DOCS_REF_URL;#source-directory'>Source Directory</ulink> - and you have sourced the environment setup script, QEMU is - installed and automatically available. - </para></listitem> - <listitem><para> - If you have downloaded a Yocto Project release and unpacked - it to create a Source Directory and you have sourced the - environment setup script, QEMU is installed and - automatically available. - </para></listitem> - <listitem><para> - If you have installed the cross-toolchain tarball and you - have sourced the toolchain's setup environment script, QEMU - is also installed and automatically available. - </para></listitem> - </itemizedlist> - </para> - </section> -</section> - -<section id='sdk-development-model'> - <title>SDK Development Model</title> - - <para> - Fundamentally, the SDK fits into the development process as follows: - <imagedata fileref="figures/sdk-environment.png" align="center" width="6in" depth="5in" scalefit="100" /> - The SDK is installed on any machine and can be used to develop - applications, images, and kernels. - An SDK can even be used by a QA Engineer or Release Engineer. - The fundamental concept is that the machine that has the SDK installed - does not have to be associated with the machine that has the - Yocto Project installed. - A developer can independently compile and test an object on their - machine and then, when the object is ready for integration into an - image, they can simply make it available to the machine that has the - Yocto Project. - Once the object is available, the image can be rebuilt using the - Yocto Project to produce the modified image. - </para> - - <para> - You just need to follow these general steps: - <orderedlist> - <listitem><para> - <emphasis>Install the SDK for your target hardware:</emphasis> - For information on how to install the SDK, see the - "<link linkend='sdk-installing-the-sdk'>Installing the SDK</link>" - section. - </para></listitem> - <listitem><para> - <emphasis>Download or Build the Target Image:</emphasis> - The Yocto Project supports several target architectures - and has many pre-built kernel images and root filesystem - images.</para> - - <para>If you are going to develop your application on - hardware, go to the - <ulink url='&YOCTO_MACHINES_DL_URL;'><filename>machines</filename></ulink> - download area and choose a target machine area - from which to download the kernel image and root filesystem. - This download area could have several files in it that - support development using actual hardware. - For example, the area might contain - <filename>.hddimg</filename> files that combine the - kernel image with the filesystem, boot loaders, and - so forth. - Be sure to get the files you need for your particular - development process.</para> - - <para>If you are going to develop your application and - then run and test it using the QEMU emulator, go to the - <ulink url='&YOCTO_QEMU_DL_URL;'><filename>machines/qemu</filename></ulink> - download area. - From this area, go down into the directory for your - target architecture (e.g. <filename>qemux86_64</filename> - for an <trademark class='registered'>Intel</trademark>-based - 64-bit architecture). - Download the kernel, root filesystem, and any other files you - need for your process. - <note> - To use the root filesystem in QEMU, you need to extract it. - See the - "<link linkend='sdk-extracting-the-root-filesystem'>Extracting the Root Filesystem</link>" - section for information on how to extract the root - filesystem. - </note> - </para></listitem> - <listitem><para> - <emphasis>Develop and Test your Application:</emphasis> - At this point, you have the tools to develop your application. - If you need to separately install and use the QEMU emulator, - you can go to - <ulink url='http://wiki.qemu.org/Main_Page'>QEMU Home Page</ulink> - to download and learn about the emulator. - See the - "<ulink url='&YOCTO_DOCS_DEV_URL;#dev-manual-qemu'>Using the Quick EMUlator (QEMU)</ulink>" - chapter in the Yocto Project Development Tasks Manual - for information on using QEMU within the Yocto - Project. - </para></listitem> - </orderedlist> - </para> - - <para> - The remainder of this manual describes how to use the extensible - and standard SDKs. - Information also exists in appendix form that describes how you can - build, install, and modify an SDK. - </para> -</section> - -</chapter> -<!-- -vim: expandtab tw=80 ts=4 ---> |