Building libreboot from source

This section relates to building libreboot from source, and working with the git repository.

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Install build dependencies

Before doing anything, you need the dependencies first. This is true if you want to build libreboot from source, with either libreboot_src.tar.xz or git. If you are using libreboot_util.tar.xz (binary archive) then you can ignore this, because ROM images and statically compiled executables for the utilities are included.

For Trisquel 7, you can run the following command:
$ sudo ./build dependencies trisquel7

For Parabola, you can run the following command:
$ sudo ./build dependencies parabola
or:
# ./build dependencies parabola

For other GNU/Linux distributions, you can adapt the existing scripts.

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Get the full source code from metadata (git clone)

If you downloaded libreboot from git, then there are some steps to download and patch the source code for all relevant dependencies. The archive in the git repository used to be available as a tarball called 'libreboot_meta.tar.gz'. It contains 'metadata' (scripts) which define how the source was created (where it came from).

You can use the scripts included to download everything.

First, install the build dependencies.

Since libreboot makes extensive use of git, you need to configure git properly. If you have not yet configured git, then the minimum requirement is:
$ git config --global user.name "Your Name"
$ git config --global user.email your@emailaddress.com
This is what will also appear in git logs if you ever commit your own changes to a given repository. For more information, see http://git-scm.com/doc.

Another nice config for you (optional, but recommended):
$ git config --global core.editor nano
$ git config --global color.status auto
$ git config --global color.branch auto
$ git config --global color.interactive auto
$ git config --global color.diff auto

After that, run the script:
$ ./download all

What this did was download everything (grub, coreboot, memtest86+, bucts, flashrom) at the versions last tested for this release, and patch them. Read the script in a text editor to learn more.

To build the ROM images, see #build.

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How to build "bucts" (for LenovoBIOS X60/X60S/X60T/T60)

This is for Lenovo BIOS users on the ThinkPad X60/X60S, X60 Tablet and T60. If you have coreboot or libreboot running already, ignore this.

BUC.TS isn't really specific to these laptops, but is a bit inside the a register in the chipset on some Intel systems.

Bucts is needed when flashing in software the X60/X60S/X60T/T60 ROM while Lenovo BIOS is running; external flashing will be safe regardless. Each ROM contains identical data inside the two final 64K region in the file*. This corresponds to the final two 64K regions in the flash chip. Lenovo BIOS will prevent you from writing the final one, so running "bucts 1" will set the machine to boot from the other block instead (which is writeable along with everything beneath it when using a patched flashrom. see #build_flashrom). After shutting down and booting up after the first flash of libreboot, the final 64K block is writeable so you flash the ROM again with an unpatched flashrom and run "bucts 0" to make the machine boot from the normal (highest) block again.

*Libreboot ROM images have identical data in those two 64KiB regions because dd is used to do that, by the build system. If you're building from upstream (coreboot), you have to do it manually.

BUC.TS is backed up (powered) by the NVRAM battery (or CMOS battery, as some people call it). On thinkpads, this is typically in a yellow plastic package with the battery inside, connected via power lines to the mainboard. Removing that battery removes power to BUC.TS, resetting the bit back to 0 (if you previously set it to 1).

BUC.TS utility is included in libreboot_src.tar.xz and libreboot_util.tar.xz.
If you downloaded from git, follow #build_meta before you proceed.

"BUC" means "Backup Control" (it's a register) and "TS" means "Top Swap" (it's a status bit). Hence "bucts" (BUC.TS). TS 1 and TS 0 corresponds to bucts 1 and bucts 0.

If you have the binary release archive, you'll find executables under ./bucts/. Otherwise if you need to build from source, continue reading.

First, install the build dependencies.

To build bucts, do this in the main directory:
$ ./build module bucts

To statically compile it, do this:
$ ./build module bucts static

The "builddeps" script in libreboot_src also makes use of builddeps-bucts.

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How to build "flashrom"

Flashrom is the utility for flashing/dumping ROM images. This is what you will use to install libreboot.

Flashrom source code is included in libreboot_src.tar.xz and libreboot_util.tar.xz.
If you downloaded from git, follow #build_meta before you proceed.

If you are using the binary release archive, then there are already binaries included under ./flashrom/. The flashing scripts will try to choose the correct one for you. Otherwise if you wish to re-build flashrom from source, continue reading.

First, install the build dependencies.

To build it, do the following in the main directory:
$ ./build module flashrom

To statically compile it, do the following in the main directory:
$ ./build module flashrom static

After you've done that, under ./flashrom/ you will find the following executables:

The "builddeps" script in libreboot_src also makes use of builddeps-flashrom.

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Configuring libreboot

Before building a ROM in libreboot (or coreboot, for that matter), you need to configure it. This is done using the following inside the source tree:
$ cd coreboot/
$ make menuconfig

If you've already built a kernel before, you know how to use this interface.

Configurations are then saved as files called ".config". Copies of each configuration used for each machine type by the libreboot build scripts are stored in resources/libreboot/config/

dmidecode

There is certain information that can be useful to enter in particular:

This information can be obtained using:
$ sudo dmidecode
# dmidecode

Specifically, it's good practise to enter the same information for libreboot that you found when running this with the original BIOS or firmware. libreboot has already done this for you. This information is for reference, in the hope that it will be useful.

ThinkPad X60, X60S and X60 Tablet configuration (file: resources/libreboot/config/x60/config)

Now go back into Devices:

The resulting .config file was saved as resources/libreboot/config/x60/config and is used by the build scripts for this machine.

This configuration is used on all variants: X60, X60S and X60 Tablet.

ThinkPad T60 configuration (file: resources/libreboot/config/t60/config)

Go back into Devices:

The resulting .config file was saved as resources/libreboot/config/t60/config and is used by the build scripts for this machine.

It is believed that the motherboards on 14.1" and 15.1" T60s are the same, so the same configuration is used on both the 14.1" and 15.1" T60s.

ThinkPad X200 configuration (file: resources/libreboot/config/x200_4mb/config and resources/libreboot/config/x200_8mb/config)

These are saved as two configs, because there are 2 size flash chips: 4MB or 8MB.

Go back and disable option ROMs:

The resulting .config file was saved as resources/libreboot/config/x200_8mb/config and resources/libreboot/config/x200_4mb/config and is used by the build scripts for this machine.

ThinkPad R400 configuration (file: resources/libreboot/config/r400_4mb/config and resources/libreboot/config/r400_8mb/config)

These are saved as two configs, because there are 2 size flash chips: 4MB or 8MB.

Go back and disable option ROMs:

The resulting .config file was saved as resources/libreboot/config/r400_8mb/config and resources/libreboot/config/r400_4mb/config and is used by the build scripts for this machine.

ThinkPad T400 configuration (file: resources/libreboot/config/t400_4mb/config and resources/libreboot/config/t400_8mb/config)

These are saved as two configs, because there are 2 size flash chips: 4MB or 8MB.

Go back and disable option ROMs:

The resulting .config file was saved as resources/libreboot/config/t400_8mb/config and resources/libreboot/config/t400_4mb/config and is used by the build scripts for this machine.

ThinkPad T500 configuration (file: resources/libreboot/config/t500_4mb/config and resources/libreboot/config/t500_8mb/config)

These are saved as two configs, because there are 2 size flash chips: 4MB or 8MB.

Go back and disable option ROMs:

The resulting .config file was saved as resources/libreboot/config/t500_8mb/config and resources/libreboot/config/t500_4mb/config and is used by the build scripts for this machine.

MacBook2,1 configuration (file: resources/libreboot/config/macbook21/config)

Go back and disable option ROMs:

The resulting .config file was saved as resources/libreboot/config/macbook21/config and is used by the build scripts for this machine. This config is also used for the MacBook1,1.

QEMU (x86 i440fx/piix4) configuration (file: resources/libreboot/config/qemu_i440fx_piix4/config)

Go back and disable option ROMs:

The resulting .config file was saved as resources/libreboot/config/qemu_i440fx_piix4/config and is used by the build scripts for this machine.

QEMU (x86 q35/ich9) configuration (file: resources/libreboot/config/qemu_q35_ich9/config)

Go back and disable option ROMs:

The resulting .config file was saved as resources/libreboot/config/qemu_q35_ich9/config and is used by the build scripts for this machine.

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How to build the ROM images

You don't need to do much, as there are scripts already written for you that can build everything automatically.

You can build libreboot from source on a 32-bit (i686) or 64-bit (x86_64) system. Recommended (if possible): x86_64. On a ThinkPad T60, you can replace the CPU (Core 2 Duo T5600, T7200 or T7600. T5600 recommended) for 64-bit support. On an X60s, you can replace the board with one that has a Core 2 Duo L7400 (you could also use an X60 Tablet board with the same CPU). On an X60, you can replace the board with one that has a Core 2 Duo T5600 or T7200 (T5600 is recommended). All MacBook2,1 laptops are 64-bit, as are all ThinkPad X200, X200S, X200 Tablet, R400, T400 and T500 laptops. Warning: MacBook1,1 laptops are all 32-bit only.

First, install the build dependencies.

If you downloaded libreboot from git, refer to #build_meta.

Build all of the components used in libreboot:
$ ./build module all

After that, build the ROM images (for all boards):
$ ./build roms withgrub
Alternatively, you can build for a specific board or set of boards. For example:
$ ./build roms withgrub x60
$ ./build roms withgrub x200_8mb
$ ./build roms withgrub x60 x200_8mb
The list of board options can be found by looking at the directory names in resources/libreboot/config/.

To clean (reverse) everything, do the following:
$ ./build clean all

The ROM images will be stored under bin/.

Preparing release archives (optional)

This is only confirmed to work (tested) in Trisquel 7. Parabola *fails* at this stage (for now).

Do the following:
$ ./build release archives

If you are building on an i686 host, this will build statically linked 32-bit binaries in the binary release archive that you created, for: nvramtool, cbfstool, ich9deblob, cbmem.

If you are building on an x86_64 host, this will build statically linked 32- *and* 64-bit binaries for cbmem, ich9deblob, cbfstool and nvramtool.

To include statically linked i686 and x86_64 binaries for bucts and flashrom, you will need to build them on a chroot, a virtual machine or a real system where the host uses each given architecture. These packages are difficult to cross-compile, and the libreboot project is still figuring out how to deal with them.

The same applies if you want to include statically linked flashrom binaries for ARM.

armv7l binaries (tested on a BeagleBone Black) are also included in libreboot_util, for:

If you are building binaries on a live system or chroot (for flashrom/bucts), you can use the following to statically link them:
$ ./build module flashrom static
$ ./build module bucts static

The same conditions as above apply for ARM (except, building bucts on ARM is pointless, and for flashrom you only need the normal executable since the lenovobios_sst and _macronix executables are meant to run on an X60/T60 while lenovo bios is present, working around the security restrictions).

The command that you used for generating the release archives will also run the following command:
$ ./build external source
The archive tobuild.tar.xz will have been created under release/, containing bucts, flashrom and all other required resources for building them.

You'll find that the files libreboot_util.tar.xz and libreboot_src.tar.xz have been created, under release/.

The ROM images will be stored in separate archives for each machine, under release/rom/.

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Copyright © 2014, 2015 Francis Rowe <info@gluglug.org.uk>
This document is released under the Creative Commons Attribution-ShareAlike 4.0 International Public License and all future versions. A copy of the license can be found at ../license.txt.

This document is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See ../license.txt for more information.