xref: /openbmc/u-boot/tools/buildman/README (revision 7ca6f363)
1# Copyright (c) 2013 The Chromium OS Authors.
2#
3# SPDX-License-Identifier:	GPL-2.0+
4#
5
6What is this?
7=============
8
9This tool handles building U-Boot to check that you have not broken it
10with your patch series. It can build each individual commit and report
11which boards fail on which commits, and which errors come up. It aims
12to make full use of multi-processor machines.
13
14A key feature of buildman is its output summary, which allows warnings,
15errors or image size increases in a particular commit or board to be
16quickly identified and the offending commit pinpointed. This can be a big
17help for anyone working with >10 patches at a time.
18
19
20Caveats
21=======
22
23Buildman is still in its infancy. It is already a very useful tool, but
24expect to find problems and send patches.
25
26Buildman can be stopped and restarted, in which case it will continue
27where it left off. This should happen cleanly and without side-effects.
28If not, it is a bug, for which a patch would be welcome.
29
30Buildman gets so tied up in its work that it can ignore the outside world.
31You may need to press Ctrl-C several times to quit it. Also it will print
32out various exceptions when stopped.
33
34
35Theory of Operation
36===================
37
38(please read this section in full twice or you will be perpetually confused)
39
40Buildman is a builder. It is not make, although it runs make. It does not
41produce any useful output on the terminal while building, except for
42progress information. All the output (errors, warnings and binaries if you
43are ask for them) is stored in output directories, which you can look at
44while the build is progressing, or when it is finished.
45
46Buildman produces a concise summary of which boards succeeded and failed.
47It shows which commit introduced which board failure using a simple
48red/green colour coding. Full error information can be requested, in which
49case it is de-duped and displayed against the commit that introduced the
50error. An example workflow is below.
51
52Buildman stores image size information and can report changes in image size
53from commit to commit. An example of this is below.
54
55Buildman starts multiple threads, and each thread builds for one board at
56a time. A thread starts at the first commit, configures the source for your
57board and builds it. Then it checks out the next commit and does an
58incremental build. Eventually the thread reaches the last commit and stops.
59If errors or warnings are found along the way, the thread will reconfigure
60after every commit, and your build will be very slow. This is because a
61file that produces just a warning would not normally be rebuilt in an
62incremental build.
63
64Buildman works in an entirely separate place from your U-Boot repository.
65It creates a separate working directory for each thread, and puts the
66output files in the working directory, organised by commit name and board
67name, in a two-level hierarchy.
68
69Buildman is invoked in your U-Boot directory, the one with the .git
70directory. It clones this repository into a copy for each thread, and the
71threads do not affect the state of your git repository. Any checkouts done
72by the thread affect only the working directory for that thread.
73
74Buildman automatically selects the correct toolchain for each board. You
75must supply suitable toolchains, but buildman takes care of selecting the
76right one.
77
78Buildman always builds a branch, and always builds the upstream commit as
79well, for comparison. It cannot build individual commits at present, unless
80(maybe) you point it at an empty branch. Put all your commits in a branch,
81set the branch's upstream to a valid value, and all will be well. Otherwise
82buildman will perform random actions. Use -n to check what the random
83actions might be.
84
85Buildman is optimised for building many commits at once, for many boards.
86On multi-core machines, Buildman is fast because it uses most of the
87available CPU power. When it gets to the end, or if you are building just
88a few commits or boards, it will be pretty slow. As a tip, if you don't
89plan to use your machine for anything else, you can use -T to increase the
90number of threads beyond the default.
91
92Buildman lets you build all boards, or a subset. Specify the subset by passing
93command-line arguments that list the desired board name, architecture name,
94SOC name, or anything else in the boards.cfg file. Multiple arguments are
95allowed. Each argument will be interpreted as a regular expression, so
96behaviour is a superset of exact or substring matching. Examples are:
97
98* 'tegra20'      All boards with a Tegra20 SoC
99* 'tegra'        All boards with any Tegra Soc (Tegra20, Tegra30, Tegra114...)
100* '^tegra[23]0$' All boards with either Tegra20 or Tegra30 SoC
101* 'powerpc'      All PowerPC boards
102
103Buildman does not store intermediate object files. It optionally copies
104the binary output into a directory when a build is successful. Size
105information is always recorded. It needs a fair bit of disk space to work,
106typically 250MB per thread.
107
108
109Setting up
110==========
111
1121. Get the U-Boot source. You probably already have it, but if not these
113steps should get you started with a repo and some commits for testing.
114
115$ cd /path/to/u-boot
116$ git clone git://git.denx.de/u-boot.git .
117$ git checkout -b my-branch origin/master
118$ # Add some commits to the branch, reading for testing
119
1202. Create ~/.buildman to tell buildman where to find tool chains. As an
121example:
122
123# Buildman settings file
124
125[toolchain]
126root: /
127rest: /toolchains/*
128eldk: /opt/eldk-4.2
129
130[toolchain-alias]
131x86: i386
132blackfin: bfin
133sh: sh4
134nds32: nds32le
135openrisc: or32
136
137
138This selects the available toolchain paths. Add the base directory for
139each of your toolchains here. Buildman will search inside these directories
140and also in any '/usr' and '/usr/bin' subdirectories.
141
142Make sure the tags (here root: rest: and eldk:) are unique.
143
144The toolchain-alias section indicates that the i386 toolchain should be used
145to build x86 commits.
146
147
1482. Check the available toolchains
149
150Run this check to make sure that you have a toolchain for every architecture.
151
152$ ./tools/buildman/buildman --list-tool-chains
153Scanning for tool chains
154   - scanning path '/'
155      - looking in '/.'
156      - looking in '/bin'
157      - looking in '/usr/bin'
158         - found '/usr/bin/gcc'
159Tool chain test:  OK
160         - found '/usr/bin/c89-gcc'
161Tool chain test:  OK
162         - found '/usr/bin/c99-gcc'
163Tool chain test:  OK
164         - found '/usr/bin/x86_64-linux-gnu-gcc'
165Tool chain test:  OK
166   - scanning path '/toolchains/powerpc-linux'
167      - looking in '/toolchains/powerpc-linux/.'
168      - looking in '/toolchains/powerpc-linux/bin'
169         - found '/toolchains/powerpc-linux/bin/powerpc-linux-gcc'
170Tool chain test:  OK
171      - looking in '/toolchains/powerpc-linux/usr/bin'
172   - scanning path '/toolchains/nds32le-linux-glibc-v1f'
173      - looking in '/toolchains/nds32le-linux-glibc-v1f/.'
174      - looking in '/toolchains/nds32le-linux-glibc-v1f/bin'
175         - found '/toolchains/nds32le-linux-glibc-v1f/bin/nds32le-linux-gcc'
176Tool chain test:  OK
177      - looking in '/toolchains/nds32le-linux-glibc-v1f/usr/bin'
178   - scanning path '/toolchains/nios2'
179      - looking in '/toolchains/nios2/.'
180      - looking in '/toolchains/nios2/bin'
181         - found '/toolchains/nios2/bin/nios2-linux-gcc'
182Tool chain test:  OK
183         - found '/toolchains/nios2/bin/nios2-linux-uclibc-gcc'
184Tool chain test:  OK
185      - looking in '/toolchains/nios2/usr/bin'
186         - found '/toolchains/nios2/usr/bin/nios2-linux-gcc'
187Tool chain test:  OK
188         - found '/toolchains/nios2/usr/bin/nios2-linux-uclibc-gcc'
189Tool chain test:  OK
190   - scanning path '/toolchains/microblaze-unknown-linux-gnu'
191      - looking in '/toolchains/microblaze-unknown-linux-gnu/.'
192      - looking in '/toolchains/microblaze-unknown-linux-gnu/bin'
193         - found '/toolchains/microblaze-unknown-linux-gnu/bin/microblaze-unknown-linux-gnu-gcc'
194Tool chain test:  OK
195         - found '/toolchains/microblaze-unknown-linux-gnu/bin/mb-linux-gcc'
196Tool chain test:  OK
197      - looking in '/toolchains/microblaze-unknown-linux-gnu/usr/bin'
198   - scanning path '/toolchains/mips-linux'
199      - looking in '/toolchains/mips-linux/.'
200      - looking in '/toolchains/mips-linux/bin'
201         - found '/toolchains/mips-linux/bin/mips-linux-gcc'
202Tool chain test:  OK
203      - looking in '/toolchains/mips-linux/usr/bin'
204   - scanning path '/toolchains/old'
205      - looking in '/toolchains/old/.'
206      - looking in '/toolchains/old/bin'
207      - looking in '/toolchains/old/usr/bin'
208   - scanning path '/toolchains/i386-linux'
209      - looking in '/toolchains/i386-linux/.'
210      - looking in '/toolchains/i386-linux/bin'
211         - found '/toolchains/i386-linux/bin/i386-linux-gcc'
212Tool chain test:  OK
213      - looking in '/toolchains/i386-linux/usr/bin'
214   - scanning path '/toolchains/bfin-uclinux'
215      - looking in '/toolchains/bfin-uclinux/.'
216      - looking in '/toolchains/bfin-uclinux/bin'
217         - found '/toolchains/bfin-uclinux/bin/bfin-uclinux-gcc'
218Tool chain test:  OK
219      - looking in '/toolchains/bfin-uclinux/usr/bin'
220   - scanning path '/toolchains/sparc-elf'
221      - looking in '/toolchains/sparc-elf/.'
222      - looking in '/toolchains/sparc-elf/bin'
223         - found '/toolchains/sparc-elf/bin/sparc-elf-gcc'
224Tool chain test:  OK
225      - looking in '/toolchains/sparc-elf/usr/bin'
226   - scanning path '/toolchains/arm-2010q1'
227      - looking in '/toolchains/arm-2010q1/.'
228      - looking in '/toolchains/arm-2010q1/bin'
229         - found '/toolchains/arm-2010q1/bin/arm-none-linux-gnueabi-gcc'
230Tool chain test:  OK
231      - looking in '/toolchains/arm-2010q1/usr/bin'
232   - scanning path '/toolchains/from'
233      - looking in '/toolchains/from/.'
234      - looking in '/toolchains/from/bin'
235      - looking in '/toolchains/from/usr/bin'
236   - scanning path '/toolchains/sh4-gentoo-linux-gnu'
237      - looking in '/toolchains/sh4-gentoo-linux-gnu/.'
238      - looking in '/toolchains/sh4-gentoo-linux-gnu/bin'
239         - found '/toolchains/sh4-gentoo-linux-gnu/bin/sh4-gentoo-linux-gnu-gcc'
240Tool chain test:  OK
241      - looking in '/toolchains/sh4-gentoo-linux-gnu/usr/bin'
242   - scanning path '/toolchains/avr32-linux'
243      - looking in '/toolchains/avr32-linux/.'
244      - looking in '/toolchains/avr32-linux/bin'
245         - found '/toolchains/avr32-linux/bin/avr32-gcc'
246Tool chain test:  OK
247      - looking in '/toolchains/avr32-linux/usr/bin'
248   - scanning path '/toolchains/m68k-linux'
249      - looking in '/toolchains/m68k-linux/.'
250      - looking in '/toolchains/m68k-linux/bin'
251         - found '/toolchains/m68k-linux/bin/m68k-linux-gcc'
252Tool chain test:  OK
253      - looking in '/toolchains/m68k-linux/usr/bin'
254List of available toolchains (17):
255arm       : /toolchains/arm-2010q1/bin/arm-none-linux-gnueabi-gcc
256avr32     : /toolchains/avr32-linux/bin/avr32-gcc
257bfin      : /toolchains/bfin-uclinux/bin/bfin-uclinux-gcc
258c89       : /usr/bin/c89-gcc
259c99       : /usr/bin/c99-gcc
260i386      : /toolchains/i386-linux/bin/i386-linux-gcc
261m68k      : /toolchains/m68k-linux/bin/m68k-linux-gcc
262mb        : /toolchains/microblaze-unknown-linux-gnu/bin/mb-linux-gcc
263microblaze: /toolchains/microblaze-unknown-linux-gnu/bin/microblaze-unknown-linux-gnu-gcc
264mips      : /toolchains/mips-linux/bin/mips-linux-gcc
265nds32le   : /toolchains/nds32le-linux-glibc-v1f/bin/nds32le-linux-gcc
266nios2     : /toolchains/nios2/bin/nios2-linux-gcc
267powerpc   : /toolchains/powerpc-linux/bin/powerpc-linux-gcc
268sandbox   : /usr/bin/gcc
269sh4       : /toolchains/sh4-gentoo-linux-gnu/bin/sh4-gentoo-linux-gnu-gcc
270sparc     : /toolchains/sparc-elf/bin/sparc-elf-gcc
271x86_64    : /usr/bin/x86_64-linux-gnu-gcc
272
273
274You can see that everything is covered, even some strange ones that won't
275be used (c88 and c99). This is a feature.
276
277
278How to run it
279=============
280
281First do a dry run using the -n flag: (replace <branch> with a real, local
282branch with a valid upstream)
283
284$ ./tools/buildman/buildman -b <branch> -n
285
286If it can't detect the upstream branch, try checking out the branch, and
287doing something like 'git branch --set-upstream <branch> upstream/master'
288or something similar.
289
290As an exmmple:
291
292Dry run, so not doing much. But I would do this:
293
294Building 18 commits for 1059 boards (4 threads, 1 job per thread)
295Build directory: ../lcd9b
296    5bb3505 Merge branch 'master' of git://git.denx.de/u-boot-arm
297    c18f1b4 tegra: Use const for pinmux_config_pingroup/table()
298    2f043ae tegra: Add display support to funcmux
299    e349900 tegra: fdt: Add pwm binding and node
300    424a5f0 tegra: fdt: Add LCD definitions for Tegra
301    0636ccf tegra: Add support for PWM
302    a994fe7 tegra: Add SOC support for display/lcd
303    fcd7350 tegra: Add LCD driver
304    4d46e9d tegra: Add LCD support to Nvidia boards
305    991bd48 arm: Add control over cachability of memory regions
306    54e8019 lcd: Add CONFIG_LCD_ALIGNMENT to select frame buffer alignment
307    d92aff7 lcd: Add support for flushing LCD fb from dcache after update
308    dbd0677 tegra: Align LCD frame buffer to section boundary
309    0cff9b8 tegra: Support control of cache settings for LCD
310    9c56900 tegra: fdt: Add LCD definitions for Seaboard
311    5cc29db lcd: Add CONFIG_CONSOLE_SCROLL_LINES option to speed console
312    cac5a23 tegra: Enable display/lcd support on Seaboard
313    49ff541 wip
314
315Total boards to build for each commit: 1059
316
317This shows that it will build all 1059 boards, using 4 threads (because
318we have a 4-core CPU). Each thread will run with -j1, meaning that each
319make job will use a single CPU. The list of commits to be built helps you
320confirm that things look about right. Notice that buildman has chosen a
321'base' directory for you, immediately above your source tree.
322
323Buildman works entirely inside the base directory, here ../lcd9b,
324creating a working directory for each thread, and creating output
325directories for each commit and board.
326
327
328Suggested Workflow
329==================
330
331To run the build for real, take off the -n:
332
333$ ./tools/buildman/buildman -b <branch>
334
335Buildman will set up some working directories, and get started. After a
336minute or so it will settle down to a steady pace, with a display like this:
337
338Building 18 commits for 1059 boards (4 threads, 1 job per thread)
339  528   36  124 /19062  1:13:30  : SIMPC8313_SP
340
341This means that it is building 19062 board/commit combinations. So far it
342has managed to succesfully build 528. Another 36 have built with warnings,
343and 124 more didn't build at all. Buildman expects to complete the process
344in an hour and 15 minutes. Use this time to buy a faster computer.
345
346
347To find out how the build went, ask for a summary with -s. You can do this
348either before the build completes (presumably in another terminal) or or
349afterwards. Let's work through an example of how this is used:
350
351$ ./tools/buildman/buildman -b lcd9b -s
352...
35301: Merge branch 'master' of git://git.denx.de/u-boot-arm
354   powerpc:   + galaxy5200_LOWBOOT
35502: tegra: Use const for pinmux_config_pingroup/table()
35603: tegra: Add display support to funcmux
35704: tegra: fdt: Add pwm binding and node
35805: tegra: fdt: Add LCD definitions for Tegra
35906: tegra: Add support for PWM
36007: tegra: Add SOC support for display/lcd
36108: tegra: Add LCD driver
36209: tegra: Add LCD support to Nvidia boards
36310: arm: Add control over cachability of memory regions
36411: lcd: Add CONFIG_LCD_ALIGNMENT to select frame buffer alignment
36512: lcd: Add support for flushing LCD fb from dcache after update
366       arm:   + lubbock
36713: tegra: Align LCD frame buffer to section boundary
36814: tegra: Support control of cache settings for LCD
36915: tegra: fdt: Add LCD definitions for Seaboard
37016: lcd: Add CONFIG_CONSOLE_SCROLL_LINES option to speed console
37117: tegra: Enable display/lcd support on Seaboard
37218: wip
373
374This shows which commits have succeeded and which have failed. In this case
375the build is still in progress so many boards are not built yet (use -u to
376see which ones). But still we can see a few failures. The galaxy5200_LOWBOOT
377never builds correctly. This could be a problem with our toolchain, or it
378could be a bug in the upstream. The good news is that we probably don't need
379to blame our commits. The bad news is it isn't tested on that board.
380
381Commit 12 broke lubbock. That's what the '+ lubbock' means. The failure
382is never fixed by a later commit, or you would see lubbock again, in green,
383without the +.
384
385To see the actual error:
386
387$ ./tools/buildman/buildman -b <branch> -se lubbock
388...
38912: lcd: Add support for flushing LCD fb from dcache after update
390       arm:   + lubbock
391+common/libcommon.o: In function `lcd_sync':
392+/u-boot/lcd9b/.bm-work/00/common/lcd.c:120: undefined reference to `flush_dcache_range'
393+arm-none-linux-gnueabi-ld: BFD (Sourcery G++ Lite 2010q1-202) 2.19.51.20090709 assertion fail /scratch/julian/2010q1-release-linux-lite/obj/binutils-src-2010q1-202-arm-none-linux-gnueabi-i686-pc-linux-gnu/bfd/elf32-arm.c:12572
394+make: *** [/u-boot/lcd9b/.bm-work/00/build/u-boot] Error 139
39513: tegra: Align LCD frame buffer to section boundary
39614: tegra: Support control of cache settings for LCD
39715: tegra: fdt: Add LCD definitions for Seaboard
39816: lcd: Add CONFIG_CONSOLE_SCROLL_LINES option to speed console
399-/u-boot/lcd9b/.bm-work/00/common/lcd.c:120: undefined reference to `flush_dcache_range'
400+/u-boot/lcd9b/.bm-work/00/common/lcd.c:125: undefined reference to `flush_dcache_range'
40117: tegra: Enable display/lcd support on Seaboard
40218: wip
403
404So the problem is in lcd.c, due to missing cache operations. This information
405should be enough to work out what that commit is doing to break these
406boards. (In this case pxa did not have cache operations defined).
407
408If you see error lines marked with - that means that the errors were fixed
409by that commit. Sometimes commits can be in the wrong order, so that a
410breakage is introduced for a few commits and fixed by later commits. This
411shows up clearly with buildman. You can then reorder the commits and try
412again.
413
414At commit 16, the error moves - you can see that the old error at line 120
415is fixed, but there is a new one at line 126. This is probably only because
416we added some code and moved the broken line futher down the file.
417
418If many boards have the same error, then -e will display the error only
419once. This makes the output as concise as possible.
420
421The full build output in this case is available in:
422
423../lcd9b/12_of_18_gd92aff7_lcd--Add-support-for/lubbock/
424
425   done: Indicates the build was done, and holds the return code from make.
426         This is 0 for a good build, typically 2 for a failure.
427
428   err:  Output from stderr, if any. Errors and warnings appear here.
429
430   log:  Output from stdout. Normally there isn't any since buildman runs
431         in silent mode for now.
432
433   toolchain: Shows information about the toolchain used for the build.
434
435   sizes: Shows image size information.
436
437It is possible to get the build output there also. Use the -k option for
438this. In that case you will also see some output files, like:
439
440   System.map  toolchain  u-boot  u-boot.bin  u-boot.map  autoconf.mk
441   (also SPL versions u-boot-spl and u-boot-spl.bin if available)
442
443
444Checking Image Sizes
445====================
446
447A key requirement for U-Boot is that you keep code/data size to a minimum.
448Where a new feature increases this noticeably it should normally be put
449behind a CONFIG flag so that boards can leave it off and keep the image
450size more or less the same with each new release.
451
452To check the impact of your commits on image size, use -S. For example:
453
454$ ./tools/buildman/buildman -b us-x86 -sS
455Summary of 10 commits for 1066 boards (4 threads, 1 job per thread)
45601: MAKEALL: add support for per architecture toolchains
45702: x86: Add function to get top of usable ram
458       x86: (for 1/3 boards)  text -272.0  rodata +41.0
45903: x86: Add basic cache operations
46004: x86: Permit bootstage and timer data to be used prior to relocation
461       x86: (for 1/3 boards)  data +16.0
46205: x86: Add an __end symbol to signal the end of the U-Boot binary
463       x86: (for 1/3 boards)  text +76.0
46406: x86: Rearrange the output input to remove BSS
465       x86: (for 1/3 boards)  bss -2140.0
46607: x86: Support relocation of FDT on start-up
467       x86: +   coreboot-x86
46808: x86: Add error checking to x86 relocation code
46909: x86: Adjust link device tree include file
47010: x86: Enable CONFIG_OF_CONTROL on coreboot
471
472
473You can see that image size only changed on x86, which is good because this
474series is not supposed to change any other board. From commit 7 onwards the
475build fails so we don't get code size numbers. The numbers are fractional
476because they are an average of all boards for that architecture. The
477intention is to allow you to quickly find image size problems introduced by
478your commits.
479
480Note that the 'text' region and 'rodata' are split out. You should add the
481two together to get the total read-only size (reported as the first column
482in the output from binutil's 'size' utility).
483
484A useful option is --step which lets you skip some commits. For example
485--step 2 will show the image sizes for only every 2nd commit (so it will
486compare the image sizes of the 1st, 3rd, 5th... commits). You can also use
487--step 0 which will compare only the first and last commits. This is useful
488for an overview of how your entire series affects code size.
489
490You can also use -d to see a detailed size breakdown for each board. This
491list is sorted in order from largest growth to largest reduction.
492
493It is possible to go a little further with the -B option (--bloat). This
494shows where U-Boot has bloted, breaking the size change down to the function
495level. Example output is below:
496
497$ ./tools/buildman/buildman -b us-mem4 -sSdB
498...
49919: Roll crc32 into hash infrastructure
500       arm: (for 10/10 boards)  all -143.4  bss +1.2  data -4.8  rodata -48.2 text -91.6
501            paz00          :  all +23  bss -4  rodata -29  text +56
502               u-boot: add: 1/0, grow: 3/-2 bytes: 168/-104 (64)
503                 function                                   old     new   delta
504                 hash_command                                80     160     +80
505                 crc32_wd_buf                                 -      56     +56
506                 ext4fs_read_file                           540     568     +28
507                 insert_var_value_sub                       688     692      +4
508                 run_list_real                             1996    1992      -4
509                 do_mem_crc                                 168      68    -100
510            trimslice      :  all -9  bss +16  rodata -29  text +4
511               u-boot: add: 1/0, grow: 1/-3 bytes: 136/-124 (12)
512                 function                                   old     new   delta
513                 hash_command                                80     160     +80
514                 crc32_wd_buf                                 -      56     +56
515                 ext4fs_iterate_dir                         672     668      -4
516                 ext4fs_read_file                           568     548     -20
517                 do_mem_crc                                 168      68    -100
518            whistler       :  all -9  bss +16  rodata -29  text +4
519               u-boot: add: 1/0, grow: 1/-3 bytes: 136/-124 (12)
520                 function                                   old     new   delta
521                 hash_command                                80     160     +80
522                 crc32_wd_buf                                 -      56     +56
523                 ext4fs_iterate_dir                         672     668      -4
524                 ext4fs_read_file                           568     548     -20
525                 do_mem_crc                                 168      68    -100
526            seaboard       :  all -9  bss -28  rodata -29  text +48
527               u-boot: add: 1/0, grow: 3/-2 bytes: 160/-104 (56)
528                 function                                   old     new   delta
529                 hash_command                                80     160     +80
530                 crc32_wd_buf                                 -      56     +56
531                 ext4fs_read_file                           548     568     +20
532                 run_list_real                             1996    2000      +4
533                 do_nandboot                                760     756      -4
534                 do_mem_crc                                 168      68    -100
535            colibri_t20_iris:  all -9  rodata -29  text +20
536               u-boot: add: 1/0, grow: 2/-3 bytes: 140/-112 (28)
537                 function                                   old     new   delta
538                 hash_command                                80     160     +80
539                 crc32_wd_buf                                 -      56     +56
540                 read_abs_bbt                               204     208      +4
541                 do_nandboot                                760     756      -4
542                 ext4fs_read_file                           576     568      -8
543                 do_mem_crc                                 168      68    -100
544            ventana        :  all -37  bss -12  rodata -29  text +4
545               u-boot: add: 1/0, grow: 1/-3 bytes: 136/-124 (12)
546                 function                                   old     new   delta
547                 hash_command                                80     160     +80
548                 crc32_wd_buf                                 -      56     +56
549                 ext4fs_iterate_dir                         672     668      -4
550                 ext4fs_read_file                           568     548     -20
551                 do_mem_crc                                 168      68    -100
552            harmony        :  all -37  bss -16  rodata -29  text +8
553               u-boot: add: 1/0, grow: 2/-3 bytes: 140/-124 (16)
554                 function                                   old     new   delta
555                 hash_command                                80     160     +80
556                 crc32_wd_buf                                 -      56     +56
557                 nand_write_oob_syndrome                    428     432      +4
558                 ext4fs_iterate_dir                         672     668      -4
559                 ext4fs_read_file                           568     548     -20
560                 do_mem_crc                                 168      68    -100
561            medcom-wide    :  all -417  bss +28  data -16  rodata -93  text -336
562               u-boot: add: 1/-1, grow: 1/-2 bytes: 88/-376 (-288)
563                 function                                   old     new   delta
564                 crc32_wd_buf                                 -      56     +56
565                 do_fat_read_at                            2872    2904     +32
566                 hash_algo                                   16       -     -16
567                 do_mem_crc                                 168      68    -100
568                 hash_command                               420     160    -260
569            tec            :  all -449  bss -4  data -16  rodata -93  text -336
570               u-boot: add: 1/-1, grow: 1/-2 bytes: 88/-376 (-288)
571                 function                                   old     new   delta
572                 crc32_wd_buf                                 -      56     +56
573                 do_fat_read_at                            2872    2904     +32
574                 hash_algo                                   16       -     -16
575                 do_mem_crc                                 168      68    -100
576                 hash_command                               420     160    -260
577            plutux         :  all -481  bss +16  data -16  rodata -93  text -388
578               u-boot: add: 1/-1, grow: 1/-3 bytes: 68/-408 (-340)
579                 function                                   old     new   delta
580                 crc32_wd_buf                                 -      56     +56
581                 do_load_serial_bin                        1688    1700     +12
582                 hash_algo                                   16       -     -16
583                 do_fat_read_at                            2904    2872     -32
584                 do_mem_crc                                 168      68    -100
585                 hash_command                               420     160    -260
586   powerpc: (for 5/5 boards)  all +37.4  data -3.2  rodata -41.8  text +82.4
587            MPC8610HPCD    :  all +55  rodata -29  text +84
588               u-boot: add: 1/0, grow: 0/-1 bytes: 176/-96 (80)
589                 function                                   old     new   delta
590                 hash_command                                 -     176    +176
591                 do_mem_crc                                 184      88     -96
592            MPC8641HPCN    :  all +55  rodata -29  text +84
593               u-boot: add: 1/0, grow: 0/-1 bytes: 176/-96 (80)
594                 function                                   old     new   delta
595                 hash_command                                 -     176    +176
596                 do_mem_crc                                 184      88     -96
597            MPC8641HPCN_36BIT:  all +55  rodata -29  text +84
598               u-boot: add: 1/0, grow: 0/-1 bytes: 176/-96 (80)
599                 function                                   old     new   delta
600                 hash_command                                 -     176    +176
601                 do_mem_crc                                 184      88     -96
602            sbc8641d       :  all +55  rodata -29  text +84
603               u-boot: add: 1/0, grow: 0/-1 bytes: 176/-96 (80)
604                 function                                   old     new   delta
605                 hash_command                                 -     176    +176
606                 do_mem_crc                                 184      88     -96
607            xpedite517x    :  all -33  data -16  rodata -93  text +76
608               u-boot: add: 1/-1, grow: 0/-1 bytes: 176/-112 (64)
609                 function                                   old     new   delta
610                 hash_command                                 -     176    +176
611                 hash_algo                                   16       -     -16
612                 do_mem_crc                                 184      88     -96
613...
614
615
616This shows that commit 19 has increased text size for arm (although only one
617board was built) and by 96 bytes for powerpc. This increase was offset in both
618cases by reductions in rodata and data/bss.
619
620Shown below the summary lines is the sizes for each board. Below each board
621is the sizes for each function. This information starts with:
622
623   add - number of functions added / removed
624   grow - number of functions which grew / shrunk
625   bytes - number of bytes of code added to / removed from all functions,
626            plus the total byte change in brackets
627
628The change seems to be that hash_command() has increased by more than the
629do_mem_crc() function has decreased. The function sizes typically add up to
630roughly the text area size, but note that every read-only section except
631rodata is included in 'text', so the function total does not exactly
632correspond.
633
634It is common when refactoring code for the rodata to decrease as the text size
635increases, and vice versa.
636
637
638Providing 'make' flags
639======================
640
641U-Boot's build system supports a few flags (such as BUILD_TAG) which affect
642the build product. These flags can be specified in the buildman settings
643file. They can also be useful when building U-Boot against other open source
644software.
645
646[make-flags]
647at91-boards=ENABLE_AT91_TEST=1
648snapper9260=${at91-boards} BUILD_TAG=442
649snapper9g45=${at91-boards} BUILD_TAG=443
650
651This will use 'make ENABLE_AT91_TEST=1 BUILD_TAG=442' for snapper9260
652and 'make ENABLE_AT91_TEST=1 BUILD_TAG=443' for snapper9g45. A special
653variable ${target} is available to access the target name (snapper9260 and
654snapper9g20 in this case). Variables are resolved recursively.
655
656It is expected that any variables added are dealt with in U-Boot's
657config.mk file and documented in the README.
658
659
660Other options
661=============
662
663Buildman has various other command line options. Try --help to see them.
664
665
666TODO
667====
668
669This has mostly be written in my spare time as a response to my difficulties
670in testing large series of patches. Apart from tidying up there is quite a
671bit of scope for improvement. Things like better error diffs, easier access
672to log files, error display while building. Also it would be nice it buildman
673could 'hunt' for problems, perhaps by building a few boards for each arch,
674or checking commits for changed files and building only boards which use
675those files.
676
677
678Credits
679=======
680
681Thanks to Grant Grundler <grundler@chromium.org> for his ideas for improving
682the build speed by building all commits for a board instead of the other
683way around.
684
685
686Simon Glass
687sjg@chromium.org
688Halloween 2012
689Updated 12-12-12
690Updated 23-02-13
691