Documentation/corebootBuildingGuide.tex

   1 %
   2 % This document is released under the GPL
   3 % Initially written by Stefan Reinauer, <stepan@coresystems.de>
   4 %
   5
   6 \documentclass[titlepage,12pt]{article}
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  24     % pdfpagemode=None,  % PDF-Viewer starts without TOC
  25     % pdfstartview=FitH,
  26     pdftitle={coreboot Porting Guide},
  27     pdfauthor={Zheng Bao},
  28     pdfsubject={coreboot configuration and build process},
  29     pdfkeywords={coreboot, AMD, configuration, Build}
  30 }
  31
  32 \setlength{\parindent}{0pt}
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  34
  35 \title{coreboot from Scratch}
  36 \author{Stefan Reinauer $<$stepan@coresystems.de$>$\and Zheng Bao $<$zheng.bao@amd.com$>$}
  37 \date{Dec 4th, 2013}
  38
  39 \begin{document}
  40
  41 \maketitle
  42
  43 \thispagestyle{empty}
  44
  45 \tableofcontents
  46
  47 \newpage
  48
  49 \section{What is coreboot}
  50 coreboot aims to replace the normal BIOS found on x86, AMD64, PPC,
  51 Alpha, and other machines with a Linux kernel that can boot Linux from a cold
  52 start. The startup code of an average coreboot port is about 500 lines of
  53 assembly and 5000 lines of C. It executes 16 instructions to get into 32bit
  54 protected mode and then performs DRAM and other hardware initializations
  55 required before Linux can take over.
  56
  57 The projects primary motivation initially was maintenance of large
  58 clusters. Not surprisingly interest and contributions have come from
  59 people with varying backgrounds.  Nowadays a large and growing number of
  60 Systems can be booted with coreboot, including embedded systems,
  61 Desktop PCs and Servers.
  62
  63 This document is used to build, modify, and port the coreboot code
  64 base on the AMD platform.
  65
  66
  67 \section{Changes}
  68
  69  \begin{itemize}
  70  \item 2013/12/20 Add Git, Gerrit, toolchains building.
  71  \item 2009/04/19 replace LinuxBIOS with coreboot
  72  \item 2004/06/02 url and language fixes from Ken Fuchs $<$kfuchs@winternet.com$>$
  73  \item 2004/02/10 ACPI and option ROM updates
  74  \item 2003/11/18 initial release
  75  \end{itemize}
  76
  77 %
  78 % Build Requirements
  79 %
  80
  81 \section{Build Requirements}
  82 To build coreboot for AMD64 from the sources you need a recent Linux.
  83 SUSE Linux 11.2, CentOS release 6.3, Fedora Core 16, Cygwin, FreeBSD,
  84 NetBSD are known to work fine.
  85
  86 To build the toolchain, you need following host compilers:
  87
  88  \begin{itemize}
  89  \item GNUtar
  90  \item GNUpatch
  91  \item GNUmake
  92  \item GCC
  93  \item binutils
  94  \item bison
  95  \item flex
  96  \item m4
  97  \item wget
  98  \end{itemize}
  99
 100 Besides the tools above, after the toolchains are built, you also need the following
 101 tools to build the source.
 102
 103  \begin{itemize}
 104  \item git: Get the source code from repository
 105  \item libncurses-dev (or ncursesw, ncurses, curses, pdcursesw, pdcurses): for menuconfig
 106  \item python: Optional for gdb.
 107  \item perl: Optional for gdb.
 108  \end{itemize}
 109
 110 %
 111 % Getting coreboot
 112 %
 113
 114 \section{Getting coreboot}
 115 The latest coreboot sources are available via GIT.
 116 For users who doesn't need to change and commit the code:
 117 { \small
 118 \begin{verbatim}
 119 $ git clone https://review.coreboot.org/coreboot
 120 \end{verbatim}
 121 }
 122 For developers, you need to get a gerrit account which you can register
 123 at \url{https://review.coreboot.org}. Please refer section ~\ref{sec:gerrit}
 124 { \small
 125 \begin{verbatim}
 126 $ git clone ssh://<username>@review.coreboot.org:29418/coreboot
 127 $ git clone https://[<username>:<password>@]review.coreboot.org/coreboot.git
 128 \end{verbatim}
 129 }
 130
 131 Checks out a sub-repository in the 3rdparty directory.
 132 { \small
 133 \begin{verbatim}
 134 $ git submodule update --init --checkout
 135 \end{verbatim}
 136 }
 137
 138 %
 139 % Building the toolchain
 140 %
 141
 142 \section{Building the toolchain}
 143 coreboot recommends and guarantees the toolchain integrated with coreboot.
 144 Linux distributions usually modify their compilers in ways incompatible with coreboot.
 145
 146 { \small
 147 \begin{verbatim}
 148 $ cd coreboot
 149 $ make crossgcc
 150 \end{verbatim}
 151 }
 152
 153 or
 154
 155 { \small
 156 \begin{verbatim}
 157 $ cd util/crossgcc
 158 $ buildgcc
 159 \end{verbatim}
 160 }
 161
 162 The buildgcc will try to get packages from website. You need to make sure you can
 163 get access the internet. Or you can get the source.tar.gz and put it in util/crossgcc/tarballs.
 164
 165 { \small
 166 \textcolor{blue} {Welcome to the} \textcolor{red} {coreboot} \textcolor{blue} {cross toolchain builder v1.23 (September 20th, 2013)}
 167
 168 Target arch is now i386-elf
 169
 170 Will skip GDB ... ok
 171
 172 Downloading tar balls ...
 173
 174  * gmp-5.1.2.tar.bz2 (cached)
 175
 176  * mpfr-3.1.2.tar.bz2 (cached)
 177
 178  * mpc-1.0.1.tar.gz (cached)
 179
 180  * libelf-0.8.13.tar.gz (cached)
 181
 182  * gcc-4.7.3.tar.bz2 (cached)
 183
 184  * binutils-2.23.2.tar.bz2 (cached)
 185
 186  * acpica-unix-20130626.tar.gz (cached)
 187
 188 Downloaded tar balls ... \textcolor {green}{ok}
 189
 190 Unpacking and patching ...
 191
 192  * gmp-5.1.2.tar.bz2
 193
 194  * mpfr-3.1.2.tar.bz2
 195
 196  * mpc-1.0.1.tar.gz
 197
 198  * libelf-0.8.13.tar.gz
 199
 200  * gcc-4.7.3.tar.bz2
 201
 202  * binutils-2.23.2.tar.bz2
 203
 204    o binutils-2.23.2\_arv7a.patch
 205
 206    o binutils-2.23.2\_no-bfd-doc.patch
 207
 208  * acpica-unix-20130626.tar.gz
 209
 210 Unpacked and patched ... \textcolor {green}{ok}
 211
 212 Building GMP 5.1.2 ... \textcolor {green}{ok}
 213
 214 Building MPFR 3.1.2 ... \textcolor {green}{ok}
 215
 216 Building MPC 1.0.1 ... \textcolor {green}{ok}
 217
 218 Building libelf 0.8.13 ... \textcolor {green}{ok}
 219
 220 Building binutils 2.23.2 ... \textcolor {green}{ok}
 221
 222 Building GCC 4.7.3 ...  ok
 223
 224 Skipping Expat (Python scripting not enabled)
 225
 226 Skipping Python (Python scripting not enabled)
 227
 228 Skipping GDB (GDB support not enabled)
 229
 230 Building IASL 20130626 ... \textcolor {green}{ok}
 231
 232 Cleaning up... \textcolor {green}{ok}
 233
 234 \textcolor {green}{You can now run your i386-elf cross toolchain from /home/baozheng/x86/coreboot-gerrit/util/crossgcc/xgcc.}
 235 }
 236 If you are lucky, you can get toolchains located in util/crossgcc/xgcc.
 237
 238 %
 239 % Build coreboot
 240 %
 241
 242 \section{Building coreboot}
 243 \subsection{Build main module of coreboot}
 244 { \small
 245 \begin{verbatim}
 246 $ cd coreboot
 247 $ make menuconfig
 248 .config - coreboot v4.0-4895-gc5025a4-dirty Configuration
 249 +------------------------ coreboot Configuration -------------------------+
 250 |  Arrow keys navigate the menu.  <Enter> selects submenus --->.          |
 251 |  Highlighted letters are hotkeys.  Pressing <Y> includes, <N> excludes, |
 252 |  <M> modularizes features.  Press <Esc><Esc> to exit, <?> for Help, </> |
 253 |  for Search.  Legend: [*] built-in  [ ] excluded  <M> module  < >       |
 254 | +---------------------------------------------------------------------+ |
 255 | |        General setup  --->                                          | |
 256 | |        Mainboard  --->                                              | |
 257 | |        Architecture (x86)  --->                                     | |
 258 | |        Chipset  --->                                                | |
 259 | |        Devices  --->                                                | |
 260 | |        VGA BIOS  --->                                               | |
 261 | |        Display  --->                                                | |
 262 | |        PXE ROM  --->                                                | |
 263 | |        Generic Drivers  --->                                        | |
 264 | |        Console  --->                                                | |
 265 | |    [ ] Relocatable Modules                                          | |
 266 | |        System tables  --->                                          | |
 267 | |        Payload  --->                                                | |
 268 | |        Debugging  --->                                              | |
 269 | |    ---                                                              | |
 270 | +----v(+)-------------------------------------------------------------+ |
 271 +-------------------------------------------------------------------------+
 272 |                    <Select>    < Exit >    < Help >                     |
 273 +-------------------------------------------------------------------------
 274 \end{verbatim}
 275 }
 276 Select Mainboard -$>$ Mainboard Vendor -$>$ AMD
 277                  -$>$ Mainboard Model  -$>$ Olive Hill
 278
 279 Then save, exit and run make.
 280
 281 { \small
 282 \begin{verbatim}
 283 $ make
 284 \end{verbatim}
 285 }
 286 The built image, coreboot.rom, is located at folder build.
 287
 288 \section{Programming coreboot to flash memory}
 289 The image resulting from a coreboot build can be directly programmed to
 290 a flash device, either using an external flash programmers, e.g., Dediprog SF100, or by using the
 291 Linux flash utility, flashrom.
 292
 293
 294 \subsection{Add modules and payload}
 295
 296 \subsubsection{VGA BIOS}
 297 There is a big Chance that you need to get a VGA BIOS.
 298 { \small
 299 \begin{verbatim}
 300 .config - coreboot v4.0 Configuration
 301 ------------------------------------------------------------------------------
 302 +-------------------------------- VGA BIOS --------------------------------+
 303 |  Arrow keys navigate the menu.  <Enter> selects submenus --->.           |
 304 |  Highlighted letters are hotkeys.  Pressing <Y> includes, <N> excludes,  |
 305 |  <M> modularizes features.  Press <Esc><Esc> to exit, <?> for Help, </>  |
 306 |  for Search.  Legend: [*] built-in  [ ] excluded  <M> module  < > module |
 307 | +----------------------------------------------------------------------+ |
 308 | |    [*] Add a VGA BIOS image                                          | |
 309 | |    (vgabios.bin) VGA BIOS path and filename                          | |
 310 | |    (1002,1306) VGA device PCI IDs                                    | |
 311 | |                                                                      | |
 312 | |                                                                      | |
 313 | |                                                                      | |
 314 | |                                                                      | |
 315 | |                                                                      | |
 316 | |                                                                      | |
 317 | +----------------------------------------------------------------------+ |
 318 +--------------------------------------------------------------------------+
 319 |                     <Select>    < Exit >    < Help >                     |
 320 +--------------------------------------------------------------------------+
 321 \end{verbatim}
 322 }
 323 Select VGA BIOS. ``The VGA device PCI IDs'' should be the same as your device. Get the
 324 Option ROM from Vendor's website.
 325
 326 \subsubsection{Payload}
 327 coreboot in itself is "only" minimal code for initializing a mainboard
 328 with peripherals. After the initialization, it jumps to a payload.
 329
 330 Currently, SeaBIOS is the most widely used payload. The best way to integrate SeaBIOS
 331 is setting it in menuconfig.
 332 { \small
 333 \begin{verbatim}
 334 +------------------------------- Payload ---------------------------------+
 335 |  Arrow keys navigate the menu.  <Enter> selects submenus --->.           |
 336 |  Highlighted letters are hotkeys.  Pressing <Y> includes, <N> excludes,  |
 337 |  <M> modularizes features.  Press <Esc><Esc> to exit, <?> for Help, </>  |
 338 |  for Search.  Legend: [*] built-in  [ ] excluded  <M> module  < > module |
 339 | +----------------------------------------------------------------------+ |
 340 | |        Add a payload (SeaBIOS)  --->                                 | |
 341 | |        SeaBIOS version (1.7.2.1)  --->                               | |
 342 | |    [*] Use LZMA compression for payloads (NEW)                       | |
 343 | |                                                                      | |
 344 | |                                                                      | |
 345 | |                                                                      | |
 346 | |                                                                      | |
 347 | |                                                                      | |
 348 | |                                                                      | |
 349 | +----------------------------------------------------------------------+ |
 350 +--------------------------------------------------------------------------+
 351 |                     <Select>    < Exit >    < Help >                     |
 352 +--------------------------------------------------------------------------+
 353 \end{verbatim}
 354 The script in Makefile will automatically checkout, config, build the SeaBIOS source,
 355 and integrat the binary into the final image.
 356
 357 %
 358 % Working with Git
 359 %
 360
 361 \section{Working with Git}
 362 \subsection{Configuration of Git}
 363 Inside the checkout you should install a commit-msg hook that adds a
 364 Change-Id into commit messages, which uniquely identifies the logical
 365 change in Gerrit even across multiple iterations of the commit. The
 366 hook only needs to be installed once per clone, and installation can
 367 be done with:
 368 { \small
 369 \begin{verbatim}
 370 $ cd coreboot
 371 $ cp ./util/gitconfig/* .git/hooks
 372 \end{verbatim}
 373 }
 374 configure your name and email in git.
 375 { \small
 376 \begin{verbatim}
 377 $ git config --global user.name "Your Name Comes Here"
 378 $ git config --global user.email your.email@example.com'
 379 \end{verbatim}
 380 }
 381 The name~\ref{user name} and email~\ref{Contact Information} should be the same the settings in gerrit.
 382 Otherwise you can not push you code to community.
 383
 384 Then run the following command once, to tell git that by default you
 385 want to submit all commits in the currently checked-out branch for
 386 review on gerrit:
 387 { \small
 388 \begin{verbatim}
 389 $ git config remote.origin.push HEAD:refs/for/main
 390 \end{verbatim}
 391 }
 392
 393 The above configurations for git has been integrated into Makefile. You can run
 394 { \small
 395 \begin{verbatim}
 396 $ make gitconfig
 397 \end{verbatim}
 398 }
 399
 400 \subsection{Work flow}
 401
 402 It is recommended that you make a new branch when you start to work, not pushing changes to main.
 403 { \small
 404 \begin{verbatim}
 405 $ git checkout main -b mybranch
 406 \end{verbatim}
 407 }
 408 After you have done your changes, run:
 409 { \small
 410 \begin{verbatim}
 411 $ git add file_need_to_submit.c
 412 $ git commit -m "my first change."
 413 \end{verbatim}
 414 }
 415
 416 % Does anyone have a better word to describe the philosophy of splitting changes to patches?
 417 You need to realize that the changes you have made should be well divided into
 418 several commits. Each of them has one and only one meaning. You could use git rebase -i to
 419 split, squash, remove, rewrite you comment.
 420
 421 Here is an example of a well-formatted commit message:
 422
 423 { \small
 424 \begin{verbatim}
 425 examplecomponent: Refactor duplicated setup into a function
 426
 427 Setting up the demo device correctly requires the exact same register
 428 values to be written into each of the PCI device functions. Moving the
 429 writes into a function allows also otherexamplecomponent to use them.
 430
 431 Signed-off-by: Joe Hacker <joe@hacker.email>
 432 \end{verbatim}
 433 }
 434
 435 Then you can push the code.
 436 { \small
 437 \begin{verbatim}
 438 $ git push
 439 \end{verbatim}
 440 }
 441
 442 You can go to the ~\ref{sec:gerrit} gerrit to see if your changes is successfully pushed.
 443
 444 Often it might happen that the patch you sent for approval is not good
 445 enough from the first attempt. Gerrit and git make it easy to track
 446 patch evolution during the review process until patches meet our
 447 quality standards and are ready for approval.
 448
 449 You can easily modify a patch sent to gerrit by you or even by someone
 450 else. Just apply it locally using one of the possible ways to do it,
 451 make a new local commit that fixes the issues reported by the
 452 reviewers, then rebase the change by preserving the same Change-ID. We
 453 recommend you to use the git rebase command in interactive mode,
 454
 455 Once your patch gets a +2 comment, your patch can be merged (cherry-pick, actually) to origin/main.
 456
 457 %
 458 % Working with Gerrit
 459 %
 460
 461 \section{Working with Gerrit}
 462 \label{sec:gerrit}
 463 If you are a coreboot user, not planning to contribute, you can skip this section.
 464 \subsection{Get gerrit account}
 465 You need to get an OpenID first. Currently Google account give you an OpenID. It means, if you have a gmail account, you have an OpenID. You can try to signed in.
 466 click \url{https://review.coreboot.org}
 467
 468 %\includegraphics[width=6.00in,height=1.00in]{gerrit_signin.png}
 469 { \small
 470 \begin{verbatim}
 471 +-----------------------------------------------------------+
 472 |All    Projects  Documentation           Register  Sign In |
 473 |Open Merged   Abandoned                                    |
 474 |Search for status:open                                     |
 475 +-----------------------------------------------------------+
 476 |Subject      Status   Owner  Project  Branch Updated CR V  |
 477 |cpu: Rename..      Alexandru coreboot main   1:20 PM +1    |
 478 |cpu: Only a..      Alexandru coreboot main   1:17 PM    X  |
 479 |arch/x86: D..      Alexandru coreboot main   1:09 PM       |
 480 |                                                           |
 481 |                                                  Next ->  |
 482 |Press '?' to view keyboard shortcuts | Powered by Gerrit   |
 483 +-----------------------------------------------------------+
 484 \end{verbatim}
 485 }
 486 Click ``Sign In'', You will get
 487
 488 %\includegraphics[width=6.00in,height=4.00in]{openid.png}
 489
 490 You will be redirected to Google to get logging in.
 491
 492 % \includegraphics[width=6.00in,height=1.50in]{login.png}
 493 { \small
 494 \begin{verbatim}
 495 Sign In to Gerrit Code Review at review.coreboot.org
 496 +--------------------------------------------------+
 497 +--------------------------------------------------+
 498 [] Remember me
 499 Sign In Cancel
 500 Sign in with a Google Account
 501 Sign in with a Yahoo! ID
 502 What is OpenID?
 503
 504 OpenID provides secure single-sign-on, without revealing your passwords to this website.
 505
 506 There are many OpenID providers available. You may already be member of one!
 507
 508 Get OpenID
 509 \end{verbatim}
 510 }
 511
 512 \subsection{Configure account}
 513 Click the dropdown button near the user name and click ``Settings''
 514
 515 % \includegraphics[width=6.00in,height=4.00in]{settings}
 516 % \epsfig{figure=keystroke_left}
 517 % \epstopdf {file=settings.eps}
 518 % \epsfig{file=settings.eps}
 519
 520 \label{user name} In ``profile'' section, type the user name for git. This probably can be changed only once.
 521 { \small
 522 \begin{verbatim}
 523 Profile               Username      zbao
 524 Preferences           Full Name     Zheng Bao
 525 Watched Projects      Email Address zheng.bao@amd.com
 526 Contact Information   Registered    Jun 28, 2011 4:33 PM
 527 SSH Public Keys       Account ID    1000034
 528 HTTP Password
 529 Identities
 530 Groups
 531 \end{verbatim}
 532 }
 533
 534 \label{Contact Information} In ``Contact Information'', enter you full name and your Email, which should be configured in your .gitconfig
 535 { \small
 536 \begin{verbatim}
 537       Full Name  __________________________________
 538 Preferred Email  ______________   Registered Email
 539
 540 Save Changes
 541 \end{verbatim}
 542 }
 543
 544 In ``SSH Public Keys'' section, upload your public key.
 545 { \small
 546 \begin{verbatim}
 547 Status  Algorithm   Key Comment
 548
 549 Delete
 550 Add SSH Public Key
 551  > How to Generate an SSH Key
 552 +--------------------------+
 553 |                          |
 554 |                          |
 555 |                          |
 556 |                          |
 557 |                          |
 558 |                          |
 559 |                          |
 560 |                          |
 561 |                          |
 562 +--------------------------+
 563 clear       Add  Close
 564 \end{verbatim}
 565 }
 566
 567 Click ``Add Key ...''
 568 Go back to you linux command line and type:
 569 { \small
 570 \begin{verbatim}
 571 $ ssh-keygen
 572 Generating public/private rsa key pair.
 573 Enter file in which to save the key (/home/zhengbao/.ssh/id_rsa):
 574 Enter passphrase (empty for no passphrase):
 575 Enter same passphrase again:
 576 Your identification has been saved in /home/zhengbao/.ssh/id_rsa.
 577 Your public key has been saved in /home/zhengbao/.ssh/id_rsa.pub.
 578 The key fingerprint is:
 579 xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx zhengb@host.domain
 580 The key's randomart image is:
 581 +--[ RSA 2048]----+
 582 |                 |
 583 |                 |
 584 |                 |
 585 |                 |
 586 |                 |
 587 |                 |
 588 |                 |
 589 |                 |
 590 |                 |
 591 +-----------------+
 592 \end{verbatim}
 593 }
 594 The data in ~/.ssh/id\_rsa.pub is your public key. Copy them to the box in the page of ``SSH Public Keys'' and click add.
 595
 596 In ``HTTP Password'' section, click button ``Generate Password''. You will get the password for http checkout.
 597 { \small
 598 \begin{verbatim}
 599 Username    XXX
 600 Password    XXXXXXXXXXXX
 601
 602 Generate Password   Clear Password
 603
 604 \end{verbatim}
 605 }
 606
 607 \subsection{Reviewing Changes}
 608 For each listed changes in Gerrit, you can review, comment, evaluate,
 609 cherry-pick, and even re-submit them. For you own patches, only you can
 610 abandon them. Click in the file and commit message, you can add in-line comment.
 611
 612 %
 613 % 14 Glossary
 614 %
 615
 616 \section{Glossary}
 617 \begin{itemize}
 618 \item payload
 619
 620 coreboot only cares about low level machine initialization, but also has
 621 very simple mechanisms to boot a file either from FLASHROM or IDE. That
 622 file, possibly a Linux Kernel, a boot loader or Etherboot, are called
 623 payload, since it is the first software executed that does not cope with
 624 pure initialization.
 625
 626 \item flash device
 627
 628 Flash devices are commonly used in all different computers since unlike
 629 ROMs they can be electronically erased and reprogrammed.
 630
 631 \item Gerrit
 632
 633 Gerrit is a web based code review system, facilitating online code
 634 reviews for projects using the Git version control system.
 635
 636 Gerrit makes reviews easier by showing changes in a side-by-side
 637 display, and allowing inline comments to be added by any reviewer.
 638
 639 Gerrit simplifies Git based project maintainership by permitting any
 640 authorized user to submit changes to the upstream Git repository, rather
 641 than requiring all approved changes to be merged in by hand by the
 642 project maintainer. This functionality enables a more centralized
 643 usage of Git.
 644
 645 \end{itemize}
 646
 647 \newpage
 648
 649 %
 650 % 14 Bibliography
 651 %
 652
 653 \section{Bibliography}
 654 \subsection{Additional Papers on coreboot}
 655
 656 \begin{itemize}
 657  \item
 658  \textit{\url{https://www.coreboot.org/Documentation}}
 659 \end{itemize}
 660
 661 \subsection {Links}
 662
 663 \begin{itemize}
 664  \item Etherboot: \textit{\url{http://www.etherboot.org/}}
 665  \item OpenBIOS: \textit{\url{http://www.openbios.org/}}
 666  \item Flashrom: \textit{\url{http://www.flashrom.org/}}
 667  \item Seabios: \textit{\url{http://www.seabios.org/}}
 668 \end{itemize}
 669
 670
 671 \end{document}