Good news for kernel hackers, and especially coreboot developers like me: AMD has released the chipset documentation for the RS780 chipset, including the BIOS Developer's Guide. And these documents are being released freely and openly to the public, no NDAs required, which is great!
The coreboot community, which includes government organizations, corporations, research labs and individuals from around the world, is very excited to expand on our existing and decade-long collaboration with AMD. This collaboration has, over the years, resulted in the inclusion of coreboot into everything from some of the largest AMD-based supercomputers in the world to some of the smallest embedded systems.
Together with the recent SB700/SB710/SB750 documentation release, the Developer Guide release for the RS780 family of Integrated Chipset/Graphics Processors enables the coreboot community to support any board with AMD chipsets out there, from embedded to enthusiast desktop and high-end server boards.
This new release once again demonstrates AMD's commitment to open standards and software that provides an improved user experience and Total Cost of Ownership for users in every walk of life. One cornerstone of this openness is the availability of documentation without NDA, enabling everyone to contribute.
Coreboot is open source, so every interested developer or user can modify, tweak and extend it to their heart's content.
An additional benefit of this documentation release is flashrom support for all AMD chipsets which enables users to reflash their BIOS/firmware/coreboot from within Linux and *BSD without rebooting.
Coreboot code for the SB700 and 780 chipset family is already being worked on by Zheng Bao at AMD in his spare time and the coreboot community is happy to work with him on finishing and integrating the code into the official coreboot codebase.
We'd like to thank Sharon Troia at AMD for making these documentation releases possible.
The exact download URLs are listed at http://www.coreboot.org/Datasheets.
I have mentioned the flashrom utility in my blog in the past. This is a small command line tool which allows you to update your BIOS/coreboot/firmware chips without opening the computer and without any special boot procedures.
Yesterday, flashrom 0.9 was finally released. Here's a short passage from the release announcement:
After nine years of development and constant improvement, we have added support for every BIOS flash ROM technology present on x86 mainboards and every flash ROM chip we ever saw in the wild.
Highlights of flashrom include:
Please note that rewriting your flash chip can be dangerous and flashrom developers make no guarantees whatsoever. That said, many users have successfully replaced proprietary tools such as awdflash, amiflash and afudos with flashrom.
Do yourself a favor and try flashrom next time you want to upgrade your BIOS. No more floppies or bootable CD-ROMs with DOS/Windows binaries or similar crap. Run flashrom conveniently from the Linux command line, or even via SSH or serial console if you want...
When trying to port coreboot (previously LinuxBIOS) to a new mainboard you're often confronted with a big problem: the BIOS/ROM chip on the respective motherboard is soldered onto the board (i.e., not in a socket).
This means that you cannot easily (hot-)swap the chip during development or for recovery purposes. So you basically have exactly one try to flash the ROM chip with a fully working/booting coreboot image. If that goes wrong your board is bricked.
This makes it pretty much impossible to develop a coreboot port for such boards (and soldered-on ROM chips are becoming more and more common, unfortunately).
However, I've recently tried to replace the soldered-on (PLCC) ROM chip on one of my boards with a socket. What sounds pretty scary at first, especially given that I have almost non-existant soldering skills, turned out to be really not that hard. Also, it can be done with relatively cheap and readily available equipment.
I have written a short HOWTO for desoldering chips and soldering on sockets in the coreboot wiki, and also finished a video showing most of the process, which I hope will be helpful for others:
$ youtube-dl -t 'http://www.youtube.com/watch?v=30x4oxyczH4'
I also tried to upload the video to Vimeo, but first they told me to install the Flash 10 abomination (and there's no way I will do that). After browsing the help/forum pages a bit I found a traditional, non-flash upload form, but that then tells me that I cannot upload Ogg Theora videos. WTF?
The Ogg Theora video support feature request has been open for more that a year. Until that issue is fixed I'll just use other video services, thanks...
Here's a nice opportunity for everyone to learn more about coreboot, a Free Software / Open Source firmware/BIOS for x86 PCs.
Ron Minnich, founder of the LinuxBIOS (now called coreboot) project, Peter Stuge of Stuge Konsult, and Stefan Reinauer of coresystems GmbH have given a presentation for the Google Tech Talks series recently. The topic was (of course) coreboot, its history, goals, features and technical details, surrounding tools and libraries such as flashrom and libpayload, as well as an automated test system for running a hardware test-suite upon every checkin in the coreboot repository.
A video of the talk, aptly named coreboot (aka LinuxBIOS): The Free/Open-Source x86 Firmware (134 MB), is available from Youtube, get it for instance via:
$ apt-get install youtube-dl $ youtube-dl http://www.youtube.com/watch?v=X72LgcMpM9k
The talk includes various demos of coreboot and various payloads you can use with coreboot. One nice example is the TINT payload, a Tetris-like game for Linux (
apt-get install tint for the curious), which has been reworked to be usable as a coreboot payload.
So, yes, you can now put Tetris in your BIOS ROM chip and play it from there (no hard drive required).
Other demos included some cluster nodes with coreboot, and a "normal" x86 desktop board booting coreboot + Linux in a very few seconds (much room left for optimizing there though, if you really want to get into fast booting).
Check out the full talk for more infos, and if you're willing to give it a try (see the list of currently supported boards), contact us on the mailing list or join the #coreboot IRC channel on Freenode.
The coreboot project (previously known as LinuxBIOS) is taking part in the Google Summer of Code™ 2008 program. This year, the project has been assigned two slots/students who will work on the following projects:
This project aims to integrate into the coreboot BIOS a payload consisting of a minimalist KVM-aware Linux kernel along with an initrd image that contains the tools needed for creating and starting guest virtual machines installed on top of it. The resulting system could host any x86(or x86-64) OS that can run over KVM (almost any major OS does), and there is a great challenge to make it as small as possible, so that it can fit in a 2MB flash image.
Currently coreboot can not boot from an arbitrary SCSI controller. There are two solutions for the problem: (1) Use Linux and Kexec. This requires to keep the SCSI driver in the flash chip. (2) Use x86emu/vm86/ADLO and the int13 method. This would allow to use the PCI option rom available on all modern SCSI controllers. So we obviously need a solution based on the latter. This could as well be implemented as a Linux program, as an intermediate payload, or as a shared library. At this point of time, I would like to implemente it as a daemon program. The program needs to catch the int13 interrupt vector that the SCSI option rom installs and make it available to arbitrary (firmware/payload) code trying to load something from disk.
This should make for an interesting summer with nice improvements for coreboot.