diff options
author | Scott Rifenbark <scott.m.rifenbark@intel.com> | 2010-11-11 11:05:19 -0800 |
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committer | Richard Purdie <rpurdie@linux.intel.com> | 2010-11-15 22:25:25 +0000 |
commit | c2f7ed472c2a9fde96fee5931612ac12ccc5e038 (patch) | |
tree | 8827cbd959348b1e2054929f2515753a4423adf2 | |
parent | b1f69283b3606be8b031f7df6a8c56816ecd97d8 (diff) | |
download | poky-c2f7ed472c2a9fde96fee5931612ac12ccc5e038.tar.gz |
Poky Reference Manual: Removed the bsp.xml file.
Because I am single-sourcing the bsp.xml file that is used both as
chapter 4 in the Poky Reference Manual and as the singe file in the BSP
Guide I removed the bsp.xml file that was local to the poky-ref-manual
folder.
Signed-off-by: Scott Rifenbark <scott.m.rifenbark@intel.com>
-rw-r--r-- | documentation/poky-ref-manual/bsp.xml | 469 |
1 files changed, 0 insertions, 469 deletions
diff --git a/documentation/poky-ref-manual/bsp.xml b/documentation/poky-ref-manual/bsp.xml deleted file mode 100644 index 3256760339..0000000000 --- a/documentation/poky-ref-manual/bsp.xml +++ /dev/null | |||
@@ -1,469 +0,0 @@ | |||
1 | <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> | ||
2 | <chapter id="bsp"> | ||
3 | |||
4 | <title>Board Support Packages (BSP) - Developers Guide</title> | ||
5 | |||
6 | <para> | ||
7 | A Board Support Package (BSP) is a collection of information that | ||
8 | defines how to support a particular hardware device, set of devices, or | ||
9 | hardware platform. | ||
10 | The BSP includes information about the hardware features | ||
11 | present on the device and kernel configuration information along with any | ||
12 | additional hardware drivers required. | ||
13 | The BSP also lists any additional software | ||
14 | components required in addition to a generic Linux software stack for both | ||
15 | essential and optional platform features. | ||
16 | </para> | ||
17 | |||
18 | <para> | ||
19 | This section (or document if you are reading the BSP Developer's Guide) defines | ||
20 | a structure for these components | ||
21 | so that BSPs follow a commonly understood layout. | ||
22 | Providing a common form allows end-users to understand and become familiar | ||
23 | with the layout. | ||
24 | A common form also encourages standardization | ||
25 | of software support of hardware. | ||
26 | </para> | ||
27 | |||
28 | <para> | ||
29 | The proposed format does have elements that are specific to the Poky and | ||
30 | OpenEmbedded build systems. | ||
31 | It is intended that this information can be | ||
32 | used by other systems besides Poky and OpenEmbedded and that it will be simple | ||
33 | to extract information and convert it to other formats if required. | ||
34 | Poky, through its standard layers mechanism, can directly accept The format | ||
35 | described as a layer. | ||
36 | The BSP captures all | ||
37 | the hardware-specific details in one place in a standard format, which is | ||
38 | useful for any person wishing to use the hardware platform regardless of | ||
39 | the build system they are using. | ||
40 | </para> | ||
41 | |||
42 | <para> | ||
43 | The BSP specification does not include a build system or other tools - | ||
44 | it is concerned with the hardware-specific components only. | ||
45 | At the end | ||
46 | distribution point you can ship the BSP combined with a build system | ||
47 | and other tools. | ||
48 | However, it is important to maintain the distinction that these | ||
49 | are separate components that happen to be combined in certain end products. | ||
50 | </para> | ||
51 | |||
52 | <section id="bsp-filelayout"> | ||
53 | <title>Example Filesystem Layout</title> | ||
54 | |||
55 | <para> | ||
56 | The BSP consists of a file structure inside a base directory, meta-bsp in this example, | ||
57 | where "bsp" is a placeholder for the machine or platform name. | ||
58 | Examples of some files that it could contain are: | ||
59 | </para> | ||
60 | |||
61 | <para> | ||
62 | <programlisting> | ||
63 | meta-bsp/ | ||
64 | meta-bsp/binary/zImage | ||
65 | meta-bsp/binary/poky-image-minimal.directdisk | ||
66 | meta-bsp/conf/layer.conf | ||
67 | meta-bsp/conf/machine/*.conf | ||
68 | meta-bsp/conf/machine/include/tune-*.inc | ||
69 | meta-bsp/packages/bootloader/bootloader_0.1.bb | ||
70 | meta-bsp/packages/linux/linux-bsp-2.6.50/*.patch | ||
71 | meta-bsp/packages/linux/linux-bsp-2.6.50/defconfig-bsp | ||
72 | meta-bsp/packages/linux/linux-bsp_2.6.50.bb | ||
73 | meta-bsp/packages/modem/modem-driver_0.1.bb | ||
74 | meta-bsp/packages/modem/modem-daemon_0.1.bb | ||
75 | meta-bsp/packages/image-creator/image-creator-native_0.1.bb | ||
76 | meta-bsp/prebuilds/ | ||
77 | </programlisting> | ||
78 | </para> | ||
79 | |||
80 | <para> | ||
81 | The following sections detail what these files and directories could contain. | ||
82 | </para> | ||
83 | |||
84 | </section> | ||
85 | |||
86 | <section id="bsp-filelayout-binary"> | ||
87 | <title>Prebuilt User Binaries (meta-bsp/binary/*)</title> | ||
88 | |||
89 | <para> | ||
90 | This optional area contains useful prebuilt kernels and userspace filesystem | ||
91 | images appropriate to the target system. | ||
92 | Users could use these to get a system | ||
93 | running and quickly get started on development tasks. | ||
94 | The exact types of binaries | ||
95 | present are highly hardware-dependent. | ||
96 | However, a README file should be present | ||
97 | that explains how to use them with the target hardware. | ||
98 | If prebuilt binaries are | ||
99 | present, source code to meet licensing requirements must also be provided in | ||
100 | some form. | ||
101 | </para> | ||
102 | |||
103 | </section> | ||
104 | |||
105 | <section id='bsp-filelayout-layer'> | ||
106 | <title>Layer Configuration (meta-bsp/conf/layer.conf)</title> | ||
107 | |||
108 | <para> | ||
109 | This file identifies the structure as a Poky layer, identifies the | ||
110 | contents of the layer and contains information about how Poky should use | ||
111 | it. | ||
112 | Generally, a standard boilerplate file consisting of the following works. | ||
113 | </para> | ||
114 | |||
115 | <para> | ||
116 | <programlisting> | ||
117 | # We have a conf directory, add to BBPATH | ||
118 | BBPATH := "${BBPATH}${LAYERDIR}" | ||
119 | |||
120 | # We have a recipes directory containing .bb and .bbappend files, add to BBFILES | ||
121 | BBFILES := "${BBFILES} ${LAYERDIR}/recipes/*/*.bb \ ${LAYERDIR}/recipes/*/*.bbappend" | ||
122 | |||
123 | BBFILE_COLLECTIONS += "bsp" | ||
124 | BBFILE_PATTERN_bsp := "^${LAYERDIR}/" | ||
125 | BBFILE_PRIORITY_bsp = "5" | ||
126 | </programlisting> | ||
127 | </para> | ||
128 | |||
129 | <para> | ||
130 | This file simply makes bitbake aware of the recipes and conf directories and is required | ||
131 | for recognition of the BSP by Poky. | ||
132 | </para> | ||
133 | |||
134 | </section> | ||
135 | |||
136 | <section id="bsp-filelayout-machine"> | ||
137 | <title>Hardware Configuration Options (meta-bsp/conf/machine/*.conf)</title> | ||
138 | |||
139 | <para> | ||
140 | The machine files bind together all the information contained elsewhere | ||
141 | in the BSP into a format that Poky/OpenEmbedded can understand. | ||
142 | If the BSP supports multiple machines, multiple machine configuration files | ||
143 | can be present. | ||
144 | These filenames correspond to the values to which users have set the MACHINE variable. | ||
145 | </para> | ||
146 | |||
147 | <para> | ||
148 | These files define things such as what kernel package to use | ||
149 | (PREFERRED_PROVIDER of virtual/kernel), what hardware drivers to | ||
150 | include in different types of images, any special software components | ||
151 | that are needed, any bootloader information, and also any special image | ||
152 | format requirements. | ||
153 | </para> | ||
154 | |||
155 | <para> | ||
156 | At least one machine file is required for a Poky BSP layer. | ||
157 | However, you can supply more than one file. | ||
158 | </para> | ||
159 | |||
160 | </section> | ||
161 | |||
162 | <section id="bsp-filelayout-tune"> | ||
163 | <title>Hardware Optimization Options (meta-bsp/conf/machine/include/tune-*.inc)</title> | ||
164 | |||
165 | <para> | ||
166 | These are shared hardware "tuning" definitions and are commonly used to | ||
167 | pass specific optimization flags to the compiler. | ||
168 | An example is tune-atom.inc: | ||
169 | </para> | ||
170 | <para> | ||
171 | <programlisting> | ||
172 | BASE_PACKAGE_ARCH = "core2" | ||
173 | TARGET_CC_ARCH = "-m32 -march=core2 -msse3 -mtune=generic -mfpmath=sse" | ||
174 | </programlisting> | ||
175 | </para> | ||
176 | <para> | ||
177 | This example defines a new package architecture called "core2" and uses the | ||
178 | specified optimization flags, which are carefully chosen to give best | ||
179 | performance on atom processors. | ||
180 | </para> | ||
181 | <para> | ||
182 | The tune file would be included by the machine definition and can be | ||
183 | contained in the BSP or referenced from one of the standard core set of | ||
184 | files included with Poky itself. | ||
185 | </para> | ||
186 | <para> | ||
187 | Both the base package architecuture file and the tune file are optional for a Poky BSP layer. | ||
188 | </para> | ||
189 | </section> | ||
190 | |||
191 | <section id='bsp-filelayout-kernel'> | ||
192 | <title>Linux Kernel Configuration (meta-bsp/packages/linux/*)</title> | ||
193 | |||
194 | <para> | ||
195 | These files make up the definition of a kernel to use with this | ||
196 | hardware. | ||
197 | In this case, it is a complete self-contained kernel with its own | ||
198 | configuration and patches. | ||
199 | However, kernels can be shared between many machines as well. | ||
200 | Following is an example: | ||
201 | <programlisting> | ||
202 | meta-bsp/packages/linux/linux-bsp_2.6.50.bb | ||
203 | </programlisting> | ||
204 | This example file is the core kernel recipe that details from where to get the kernel | ||
205 | source. | ||
206 | All standard source code locations are supported so this could | ||
207 | be a release tarball, some git repository, or source included in | ||
208 | the directory within the BSP itself. | ||
209 | </para> | ||
210 | <para> | ||
211 | The file then contains information about what patches to apply and how to configure and build them. | ||
212 | It can reuse the main Poky kernel build class, so the definitions here can remain very simple. | ||
213 | </para> | ||
214 | <para> | ||
215 | <programlisting> | ||
216 | linux-bsp-2.6.50/*.patch | ||
217 | </programlisting> | ||
218 | </para> | ||
219 | <para> | ||
220 | The above example file contains patches you can apply against the base kernel, from wherever | ||
221 | they may have been obtained. | ||
222 | </para> | ||
223 | <para> | ||
224 | <programlisting> | ||
225 | meta-bsp/packages/linux/linux-bsp-2.6.50/defconfig-bsp | ||
226 | </programlisting> | ||
227 | </para> | ||
228 | <para> | ||
229 | Finally, this last example file contains kernel configuration information. | ||
230 | </para> | ||
231 | <para> | ||
232 | Examples of kernel recipes are available in Poky itself. | ||
233 | These files are optional since a kernel from Poky could be selected, although it | ||
234 | would be unusual not to have a kernel configuration. | ||
235 | </para> | ||
236 | </section> | ||
237 | |||
238 | <section id='bsp-filelayout-packages'> | ||
239 | <title>Other Software (meta-bsp/packages/*)</title> | ||
240 | |||
241 | <para> | ||
242 | This section describes other pieces of software that the hardware might need for best | ||
243 | operation. | ||
244 | This section shows examples of the kinds of things that you could encounter. | ||
245 | The examples are standard <filename>.bb</filename> file recipes in the | ||
246 | usual Poky format. | ||
247 | You can include the source directly by referring to it in the source control system or | ||
248 | the released tarballs of external software projects. | ||
249 | You only need to provide these types of files if the platform requires them. | ||
250 | </para> | ||
251 | <para> | ||
252 | The following file is a bootloader recipe that can be used to generate a new | ||
253 | bootloader binary. | ||
254 | Sometimes these files are included in the final image format and are needed to re-flash hardware. | ||
255 | </para> | ||
256 | <para> | ||
257 | <programlisting> | ||
258 | meta-bsp/packages/bootloader/bootloader_0.1.bb | ||
259 | </programlisting> | ||
260 | </para> | ||
261 | <para> | ||
262 | These next two files are examples of a hardware driver and a hardware daemon that might need | ||
263 | to be included in images to make the hardware useful. | ||
264 | Although the example uses "modem" there may be other components needed, such as firmware. | ||
265 | </para> | ||
266 | <para> | ||
267 | <programlisting> | ||
268 | meta-bsp/packages/modem/modem-driver_0.1.bb | ||
269 | meta-bsp/packages/modem/modem-daemon_0.1.bb | ||
270 | </programlisting> | ||
271 | </para> | ||
272 | <para> | ||
273 | Sometimes the device needs an image in a very specific format so that the update | ||
274 | mechanism can accept and re-flash it. | ||
275 | Recipes to build the tools needed to do this can be included with the BSP. | ||
276 | Following is an example. | ||
277 | </para> | ||
278 | <para> | ||
279 | <programlisting> | ||
280 | meta-bsp/packages/image-creator/image-creator-native_0.1.bb | ||
281 | </programlisting> | ||
282 | </para> | ||
283 | </section> | ||
284 | |||
285 | <section id='bs-filelayout-bbappend'> | ||
286 | <title>Append BSP-Specific Information to Existing Recipes</title> | ||
287 | <para> | ||
288 | Suppose you have a recipe such as 'pointercal' that requires machine-specific information. | ||
289 | At the same time, you have your new BSP code nicely partitioned into a layer through which | ||
290 | you would also like to specify any machine-specific information associated with your new machine. | ||
291 | Before the <filename>.bbappend</filename> extension was introduced, you would have to copy the whole | ||
292 | pointercal recipe and files into your layer and then add the single file for your machine. | ||
293 | </para> | ||
294 | <para> | ||
295 | With the <filename>.bbappend</filename> extension, however, your work becomes much easier. | ||
296 | This extension allows you to easily merge BSP-specific information with the original recipe. | ||
297 | Whenever bitbake finds any <filename>.bbappend</filename> files they will be | ||
298 | included after bitbake loads the associated <filename>.bb</filename> but before any finalize | ||
299 | or anonymous methods run. | ||
300 | This allows the BSP layer to do whatever it might want to do to customize the original recipe. | ||
301 | </para> | ||
302 | <para> | ||
303 | If your recipe needs to reference extra files it can use the FILESEXTRAPATH variable | ||
304 | to specify their location. | ||
305 | The example below shows extra files contained in a folder called ${PN} (the package name). | ||
306 | </para> | ||
307 | <programlisting> | ||
308 | FILESEXTRAPATHS := "${THISDIR}/${PN}" | ||
309 | </programlisting> | ||
310 | <para> | ||
311 | This technique allows the BSP to add machine-specific configuration files to the layer directory, | ||
312 | which will be picked up by bitbake. | ||
313 | For an example see <filename>meta-emenlow/packages/formfactor</filename>. | ||
314 | </para> | ||
315 | </section> | ||
316 | |||
317 | <section id="bsp-filelayout-prebuilds"> | ||
318 | <title>Prebuild Data (meta-bsp/prebuilds/*)</title> | ||
319 | <para> | ||
320 | This location can contain precompiled representations of the source code | ||
321 | contained elsewhere in the BSP layer. | ||
322 | Assuming a compatible configuration is used, Poky can process and use these optional precompiled | ||
323 | representations to provide much faster build times. | ||
324 | </para> | ||
325 | </section> | ||
326 | |||
327 | <section id='bsp-click-through-licensing'> | ||
328 | <title>BSP 'Click-Through' Licensing Procedure</title> | ||
329 | |||
330 | <note><para> This section describes how | ||
331 | click-through licensing is expected to work. | ||
332 | Currently, this functionality is not yet implemented. | ||
333 | </para></note> | ||
334 | |||
335 | <para> | ||
336 | In some cases, a BSP contains separately licensed IP | ||
337 | (Intellectual Property) for a component that imposes | ||
338 | upon the user a requirement to accept the terms of a | ||
339 | 'click-through' license. | ||
340 | Once the license is accepted the | ||
341 | Poky build system can then build and include the | ||
342 | corresponding component in the final BSP image. | ||
343 | Some affected components might be essential to the normal | ||
344 | functioning of the system and have no 'free' replacement | ||
345 | (i.e. the resulting system would be non-functional | ||
346 | without them). | ||
347 | On the other hand, other components might be simply | ||
348 | 'good-to-have' or purely elective, or if essential | ||
349 | nonetheless have a 'free' (possibly less-capable) | ||
350 | version that could be used as a in the BSP recipe. | ||
351 | </para> | ||
352 | |||
353 | <para> | ||
354 | For cases where you can substitute something and still maintain functionality, the Poky website will make | ||
355 | available a 'de-featured' BSP completely free of | ||
356 | the encumbered IP. | ||
357 | In that case you can use the substitution directly and without | ||
358 | any further licensing requirements. | ||
359 | If present, this | ||
360 | fully 'de-featured' BSP will be named meta-bsp (i.e. the | ||
361 | normal default naming convention). | ||
362 | If available, this is the simplest the most preferred option. | ||
363 | This, of course, assumes the resulting functionality meets requirements. | ||
364 | </para> | ||
365 | |||
366 | <para> | ||
367 | If however, a non-encumbered version is unavailable or | ||
368 | the 'free' version would provide unsuitable | ||
369 | functionality or quality, an encumbered version can be | ||
370 | used. | ||
371 | Encumbered versions of a BSP are given names of | ||
372 | the form meta-bsp-nonfree. | ||
373 | </para> | ||
374 | |||
375 | <para> | ||
376 | Several methods exist within the Poky build system to satisfy the licensing | ||
377 | requirements for an encumbered BSP. | ||
378 | The following list describes them in preferential order: | ||
379 | </para> | ||
380 | |||
381 | <orderedlist> | ||
382 | <listitem> | ||
383 | |||
384 | <para> | ||
385 | Get a license key (or keys) for the encumbered BSP | ||
386 | by visiting | ||
387 | <ulink url='https://pokylinux.org/bsp-keys.html'>https://pokylinux.org/bsp-keys.html</ulink> | ||
388 | and give the name of the BSP and your e-mail address in the web form. | ||
389 | </para> | ||
390 | |||
391 | <programlisting> | ||
392 | [screenshot of dialog box] | ||
393 | </programlisting> | ||
394 | |||
395 | <para> | ||
396 | After agreeing to any applicable license terms, the | ||
397 | BSP key(s) will be immediately sent to the address | ||
398 | you gave and you can use them by specifying BSPKEY_<keydomain> | ||
399 | environment variables when building the image: | ||
400 | </para> | ||
401 | |||
402 | <programlisting> | ||
403 | $ BSPKEY_<keydomain>=<key> bitbake poky-image-sato | ||
404 | </programlisting> | ||
405 | |||
406 | <para> | ||
407 | These steps allow the encumbered image to be built | ||
408 | with no change at all to the normal build process. | ||
409 | </para> | ||
410 | |||
411 | <para> | ||
412 | Equivalently and probably more conveniently, a line | ||
413 | for each key can instead be put into the user's | ||
414 | <filename>local.conf</filename> file. | ||
415 | </para> | ||
416 | |||
417 | <para> | ||
418 | The <keydomain> component of the | ||
419 | BSPKEY_<keydomain> is required because there | ||
420 | might be multiple licenses in effect for a give BSP. | ||
421 | In such cases, a given <keydomain> corresponds to | ||
422 | a particular license. In order for an encumbered | ||
423 | BSP that encompasses multiple key domains to be built | ||
424 | successfully, a <keydomain> entry for each | ||
425 | applicable license must be present in <filename>local.conf</filename> or | ||
426 | supplied on the command-line. | ||
427 | </para> | ||
428 | </listitem> | ||
429 | <listitem> | ||
430 | <para> | ||
431 | Do nothing - build as you normally would. | ||
432 | When a license is needed the build will stop and prompt you with instructions. | ||
433 | Follow the license prompts that originate from the | ||
434 | encumbered BSP. | ||
435 | These prompts usually take the form of instructions | ||
436 | needed to manually fetch the encumbered package(s) | ||
437 | and md5 sums into the required directory (e.g. the poky/build/downloads) | ||
438 | Once the manual package fetch has been | ||
439 | completed, restart the build to continue where | ||
440 | it left off. | ||
441 | During the build the prompt will not appear again since you have satisfied the | ||
442 | requirement. | ||
443 | </para> | ||
444 | </listitem> | ||
445 | <listitem> | ||
446 | <para> | ||
447 | Get a full-featured BSP recipe rather than a key, by | ||
448 | visiting | ||
449 | <ulink url='https://pokylinux.org/bsps.html'>https://pokylinux.org/bsps.html</ulink>. | ||
450 | Accepting the license agreement(s) presented will | ||
451 | subsequently allow you to download a tarball | ||
452 | containing a full-featured BSP that is legally cleared for | ||
453 | your use by the just-given license agreement(s). | ||
454 | This method will also allow the encumbered image to | ||
455 | be built with no change at all to the normal build | ||
456 | process. | ||
457 | </para> | ||
458 | </listitem> | ||
459 | </orderedlist> | ||
460 | <para> | ||
461 | Note that the third method is also the only option available | ||
462 | when downloading pre-compiled images generated from | ||
463 | non-free BSPs. | ||
464 | Those images are likewise available at | ||
465 | <ulink url='https://pokylinux.org/bsps.html'>https://pokylinux.org/bsps.html</ulink>. | ||
466 | </para> | ||
467 | </section> | ||
468 | |||
469 | </chapter> | ||