From fd02be86862892f091c4ddf33a69e23f122d0fa2 Mon Sep 17 00:00:00 2001 From: Scott Rifenbark Date: Wed, 27 Jul 2011 11:50:26 -0700 Subject: documentation/dev-manual/dev-manual-bsp-appendix.xml: removed redundancies Some of the more general BSP development information was more appropriate in the dev-manual-cases chapter. I removed this information and left example-specific (mostly) text. (From yocto-docs rev: d44c0fa8bdea9a2cad51ae3ca4b861a12d9fcdf9) Signed-off-by: Scott Rifenbark Signed-off-by: Richard Purdie --- .../dev-manual/dev-manual-bsp-appendix.xml | 148 ++------------------- 1 file changed, 10 insertions(+), 138 deletions(-) (limited to 'documentation') diff --git a/documentation/dev-manual/dev-manual-bsp-appendix.xml b/documentation/dev-manual/dev-manual-bsp-appendix.xml index 9ccad105b7..3c0ab28d2b 100644 --- a/documentation/dev-manual/dev-manual-bsp-appendix.xml +++ b/documentation/dev-manual/dev-manual-bsp-appendix.xml @@ -54,29 +54,15 @@ 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. + For this example, the base BSP is the Intel Atom Processor E660 with Intel Platform + Controller Hub EG20T Development Kit, which is otherwise referred to as "Crown Bay." + The BSP layer is meta-crownbay. - 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.” + For information on how to choose a base BSP, see + Developing a Board Support Package (BSP) + earlier in this manual. @@ -90,7 +76,7 @@ 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. - See the Getting Setup earlier in this manual + See Getting Setup earlier in this manual for information on how to get the BSP files. @@ -119,48 +105,11 @@ Now that you have the local Yocto Project files and the base BSP files you need to create a new layer for your BSP. + To create your BSP layer you simply copy the meta-crownbay + layer to a new 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. - - - - 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>. @@ -485,22 +434,6 @@
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: @@ -559,67 +492,6 @@
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. -- cgit v1.2.3-54-g00ecf