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Diffstat (limited to 'poky/documentation/bsp-guide/bsp.xml')
| -rw-r--r-- | poky/documentation/bsp-guide/bsp.xml | 97 |
1 files changed, 52 insertions, 45 deletions
diff --git a/poky/documentation/bsp-guide/bsp.xml b/poky/documentation/bsp-guide/bsp.xml index 58f5733f7..96c0455f6 100644 --- a/poky/documentation/bsp-guide/bsp.xml +++ b/poky/documentation/bsp-guide/bsp.xml @@ -19,7 +19,7 @@ </para> <para> - This guide presents information about BSP Layers, defines a structure for components + This guide presents information about BSP layers, defines a structure for components so that BSPs follow a commonly understood layout, discusses how to customize a recipe for a BSP, addresses BSP licensing, and provides information that shows you how to create a @@ -34,7 +34,7 @@ <para> A BSP consists of a file structure inside a base directory. Collectively, you can think of the base directory, its file structure, - and the contents as a BSP Layer. + and the contents as a <firstterm>BSP layer</firstterm>. Although not a strict requirement, BSP layers in the Yocto Project use the following well-established naming convention: <literallayout class='monospaced'> @@ -69,9 +69,9 @@ Each repository is a BSP layer supported by the Yocto Project (e.g. <filename>meta-raspberrypi</filename> and <filename>meta-intel</filename>). - Each of these layers is a repository unto itself and clicking on a - layer reveals information that includes two links from which you can choose - to set up a clone of the layer's repository on your local host system. + Each of these layers is a repository unto itself and clicking on + the layer name displays two URLs from which you can + clone the layer's repository to your local system. Here is an example that clones the Raspberry Pi BSP layer: <literallayout class='monospaced'> $ git clone git://git.yoctoproject.org/meta-raspberrypi @@ -83,12 +83,13 @@ <filename>meta-yocto-bsp</filename> layer is part of the shipped <filename>poky</filename> repository. The <filename>meta-yocto-bsp</filename> layer maintains several - BSPs such as the Beaglebone, EdgeRouter, and generic versions of + "reference" BSPs including the ARM-based Beaglebone, MIPS-based + EdgeRouter, and generic versions of both 32-bit and 64-bit IA machines. </para> <para> - For information on the BSP development workflow, see the + For information on typical BSP development workflow, see the "<link linkend='developing-a-board-support-package-bsp'>Developing a Board Support Package (BSP)</link>" section. For more information on how to set up a local copy of source files @@ -98,12 +99,12 @@ </para> <para> - The layer's base directory + The BSP layer's base directory (<filename>meta-<replaceable>bsp_root_name</replaceable></filename>) - is the root directory of the BSP Layer. + is the root directory of that Layer. This directory is what you add to the <ulink url='&YOCTO_DOCS_REF_URL;#var-BBLAYERS'><filename>BBLAYERS</filename></ulink> - variable in the <filename>conf/bblayers.conf</filename> file found in the + variable in the <filename>conf/bblayers.conf</filename> file found in your <ulink url='&YOCTO_DOCS_REF_URL;#build-directory'>Build Directory</ulink>, which is established after you run the OpenEmbedded build environment setup script (i.e. @@ -153,6 +154,20 @@ layer. The <filename>meta-openembedded</filename> layer contains many <filename>meta-*</filename> layers. + In cases like this, you need to include the names of the actual + layers you want to work with, such as: + <literallayout class='monospaced'> + BBLAYERS ?= " \ + /usr/local/src/yocto/meta \ + /usr/local/src/yocto/meta-poky \ + /usr/local/src/yocto/meta-yocto-bsp \ + /usr/local/src/yocto/meta-mylayer \ + .../meta-openembedded/meta-oe \ + .../meta-openembedded/meta-perl \ + .../meta-openembedded/meta-networking \ + " + </literallayout> + and so on. </para> <para> @@ -351,25 +366,24 @@ layer combined with a build system and other tools. Realize that it is important to maintain the distinction that the BSP layer, a build system, and tools are - separate components that could to be combined in + separate components that could be combined in certain end products. </para> <para> - Before looking at the common form for the file structure - inside a BSP Layer, you should be aware that some + Before looking at the recommended form for the directory structure + inside a BSP layer, you should be aware that some requirements do exist in order for a BSP layer to - be considered compliant with the Yocto Project. + be considered <firstterm>compliant</firstterm> with the Yocto Project. For that list of requirements, see the "<link linkend='released-bsp-requirements'>Released BSP Requirements</link>" section. </para> <para> - Below is the common form for the file structure - inside a BSP Layer. + Below is the typical directory structure for a BSP layer. While this basic form represents the standard, - realize that the actual file structures for specific + realize that the actual layout for individual BSPs could differ. <literallayout class='monospaced'> meta-<replaceable>bsp_root_name</replaceable>/ @@ -567,7 +581,7 @@ for the BSP. The type or types of files here can vary depending on the licensing requirements. - For example, in the Raspberry Pi BSP all licensing + For example, in the Raspberry Pi BSP, all licensing requirements are handled with the <filename>COPYING.MIT</filename> file. </para> @@ -802,7 +816,7 @@ <ulink url='&YOCTO_DOCS_REF_URL;#source-directory'>Source Directory</ulink>. For example, many <filename>tune-*</filename> files (e.g. <filename>tune-arm1136jf-s.inc</filename>, - <filename>tun-1586-nlp.inc</filename>, and so forth) + <filename>tune-1586-nlp.inc</filename>, and so forth) reside in the <filename>poky/meta/conf/machine/include</filename> directory. @@ -834,7 +848,7 @@ This optional directory contains miscellaneous recipe files for the BSP. Most notably would be the formfactor files. - For example, in the Raspberry Pi BSP there is the + For example, in the Raspberry Pi BSP, there is the <filename>formfactor_0.0.bbappend</filename> file, which is an append file used to augment the recipe that starts the build. @@ -901,7 +915,7 @@ The <filename>*.bb</filename> files would be a developer-supplied kernel recipe. This area of the BSP hierarchy can contain both these - types of files, although in practice, it is likely that + types of files although, in practice, it is likely that you would have one or the other. </para> @@ -976,7 +990,7 @@ <title>Developing a Board Support Package (BSP)</title> <para> - This section contains the high-level procedure you can + This section describes the high-level procedure you can follow to create a BSP. Although not required for BSP creation, the <filename>meta-intel</filename> repository, which @@ -1075,10 +1089,6 @@ (<filename>beaglebone-yocto</filename>) </para></listitem> <listitem><para> - Freescale MPC8315E-RDB - (<filename>mpc8315e-rdb</filename>) - </para></listitem> - <listitem><para> Ubiquiti Networks EdgeRouter Lite (<filename>edgerouter</filename>) </para></listitem> @@ -1302,7 +1312,7 @@ (<filename>openembedded-core</filename>) or the Source Directory (<filename>poky</filename>). In other words, make sure you place related - files in appropriately related + files in appropriately-related <filename>recipes-*</filename> subdirectories specific to the recipe's function, or within a subdirectory containing a set of closely-related @@ -1319,7 +1329,7 @@ directory. This license covers the BSP Metadata as a whole. You must specify which license to use since no - default license exists when one not specified. + default license exists when one is not specified. See the <ulink url='&YOCTO_GIT_URL;/cgit.cgi/meta-raspberrypi/tree/COPYING.MIT'><filename>COPYING.MIT</filename></ulink> file for the Raspberry Pi BSP in the @@ -1342,12 +1352,10 @@ file should contain the following: <itemizedlist> <listitem><para> - A brief description about the hardware the BSP - targets. + A brief description of the target hardware. </para></listitem> <listitem><para> - A list of all the dependencies - on which a BSP layer depends. + A list of all the dependencies of the BSP. These dependencies are typically a list of required layers needed to build the BSP. @@ -1610,7 +1618,7 @@ <title>BSP Licensing Considerations</title> <para> - In some cases, a BSP contains separately licensed + In some cases, a BSP contains separately-licensed Intellectual Property (IP) for a component or components. For these cases, you are required to accept the terms of a commercial or other type of license that requires @@ -1623,7 +1631,7 @@ </para> <para> - You could find that some separately licensed components + You could find that some separately-licensed components that are essential for normal operation of the system might not have an unencumbered (or free) substitute. Without these essential components, the system would be @@ -1631,7 +1639,7 @@ Then again, you might find that other licensed components that are simply 'good-to-have' or purely elective do have an unencumbered, free replacement component that you can - use rather than agreeing to the separately licensed + use rather than agreeing to the separately-licensed component. Even for components essential to the system, you might find an unencumbered component that is not identical but @@ -1744,7 +1752,7 @@ <para> The <filename>bitbake-layers create-layer</filename> script automates creating a BSP layer. - What makes a layer a "BSP layer", is the presence of a machine + What makes a layer a "BSP layer" is the presence of at least one machine configuration file. Additionally, a BSP layer usually has a kernel recipe or an append file that leverages off an existing kernel recipe. @@ -1868,11 +1876,14 @@ </para> <para> - Machine configuration files exist in the + One or more machine configuration files exist in the <replaceable>bsp_layer</replaceable><filename>/conf/machine/</filename> directory of the layer: <literallayout class='monospaced'> - <replaceable>bsp_layer</replaceable><filename>/conf/machine/</filename><replaceable>machine</replaceable><filename>.conf</filename> + <replaceable>bsp_layer</replaceable><filename>/conf/machine/</filename><replaceable>machine1</replaceable><filename>.conf</filename> + <replaceable>bsp_layer</replaceable><filename>/conf/machine/</filename><replaceable>machine2</replaceable><filename>.conf</filename> + <replaceable>bsp_layer</replaceable><filename>/conf/machine/</filename><replaceable>machine3</replaceable><filename>.conf</filename> + ... more ... </literallayout> For example, the machine configuration file for the <ulink url='http://beagleboard.org/bone'>BeagleBone and BeagleBone Black development boards</ulink> @@ -1923,8 +1934,8 @@ IMAGE_BOOT_FILES ?= "u-boot.${UBOOT_SUFFIX} MLO zImage am335x-bone.dtb am335x-boneblack.dtb am335x-bonegreen.dtb" </literallayout> The variables used to configure the machine define - machine-specific properties. - For example, machine-dependent packages, machine + machine-specific properties; + for example, machine-dependent packages, machine tunings, the type of kernel to build, and U-Boot configurations. </para> @@ -1935,7 +1946,7 @@ machine configuration file for the BeagleBone development boards. Realize that much more can be defined as part of - a machines configuration file. + a machine's configuration file. In general, you can learn about related variables that this example does not have by locating the variables in the @@ -2182,7 +2193,6 @@ KBRANCH_genericx86-64 = "v5.0/standard/base" KBRANCH_edgerouter = "v5.0/standard/edgerouter" KBRANCH_beaglebone-yocto = "v5.0/standard/beaglebone" - KBRANCH_mpc8315e-rdb = "v5.0/standard/fsl-mpc8315e-rdb" KMACHINE_genericx86 ?= "common-pc" KMACHINE_genericx86-64 ?= "common-pc-64" @@ -2192,19 +2202,16 @@ SRCREV_machine_genericx86-64 ?= "3df4aae6074e94e794e27fe7f17451d9353cdf3d" SRCREV_machine_edgerouter ?= "3df4aae6074e94e794e27fe7f17451d9353cdf3d" SRCREV_machine_beaglebone-yocto ?= "3df4aae6074e94e794e27fe7f17451d9353cdf3d" - SRCREV_machine_mpc8315e-rdb ?= "8b62af7f252af10588276802c4c6d7c502e875be" COMPATIBLE_MACHINE_genericx86 = "genericx86" COMPATIBLE_MACHINE_genericx86-64 = "genericx86-64" COMPATIBLE_MACHINE_edgerouter = "edgerouter" COMPATIBLE_MACHINE_beaglebone-yocto = "beaglebone-yocto" - COMPATIBLE_MACHINE_mpc8315e-rdb = "mpc8315e-rdb" LINUX_VERSION_genericx86 = "5.0.3" LINUX_VERSION_genericx86-64 = "5.0.3" LINUX_VERSION_edgerouter = "5.0.3" LINUX_VERSION_beaglebone-yocto = "5.0.3" - LINUX_VERSION_mpc8315e-rdb = "5.0.3" </literallayout> This particular append file works for all the machines that are part of the |