The wiki is being retired!
Documentation is now handled by the same processes we use for code: Add something to the Documentation/ directory in the coreboot repo, and it will be rendered to https://doc.coreboot.org/. Contributions welcome!
|IDE using CF-to-IDE adapter||?||—|
|SATA||WIP||There are issues with disk detection on the CK804 chipset. This is being investigated.|
|PCI add-on cards||?||—|
|PCI Express add-on cards||?||—|
|Serial port (COM1)||Works||Serial console for coreboot and Linux is fully operational.|
|CPU frequency scaling / powersave modes||?||Probably won't work as long as there's no ACPI implementation for this board(?)|
Before you begin
Do yourself a favor, and get a BiosSavior before you begin. There are different models, make sure you order the one you need. It depends on the size and type of the ROM chip on your board. Our S2891 board has an 8Mbit PLCC chip. This is the list of BiosSavior vendors:
Unfortunately the largest BiosSavior of the PMC type is only 512Kbyte; the proprietary BIOS is 1024Kbyte large. You can build a coreboot image in 512Kbyte, so this should not be a problem; you may want to buy a couple of extra 1Mbyte PLCC chips to save a copy of the original BIOS, and put it somewhere safe.
While coreboot replaces the functions of the proprietary BIOS, it does not replace the VGA BIOS. If you want VGA on your corebooted machine (not strictly necessary for servers), you will need to extract the VGA BIOS and concatenate it with the coreboot image, before burning it to your ROM. See below for details.
This wiki page is maintained by Ward Vandewege (ward at gnu dot org).
The S2891 comes with a 8Mbit BIOS chip (SST 49LF080A). This is sufficient to have a fully functional coreboot with FILO or LAB payload, as described below.
coreboot requires a payload to boot an operating system.
If you want to boot from the network, you will need to use Etherboot.
If you want to boot from an IDE drive, USB stick or CDROM, you can use FILO.
Booting from SATA is a bit harder; the CK804 chipset on this board does not support a legacy IDE mode, so FILO and Etherboot can not boot directly from SATA.
In order to boot from SATA, we need to use 'linux-as-a-bootloader' (LAB) as a payload. You will need a 1MB ROM chip (thankfully the S2891 comes with a 1MB ROM chip) for this payload. It consists of a (stripped down) kernel + busybox, which can then be used to kexec a kernel from disk. If your disks are playing up, you will still have a busybox environment on boot, which could be useful for debugging.
Building the payload
You can build a coreboot image with a kconfig-style configuration tool (buildrom) if you want to use FILO or LAB. This is by far the easiest way to build a ROM image.
Check out buildrom:
svn co svn://coreboot.org/buildrom
Now configure buildrom:
cd buildrom/buildrom-devel make menuconfig
Configure to your liking. If you use the LAB payload, make sure to exclude the kexec binary and boot menu from the initramfs, otherwise your image will be too big. Please note that currently only the FILO and LAB payloads have been tested. The other payloads likely require some more work before they will be useable. Patches are welcome, of course.
If all goes well, you should now have a ROM image file
This image will be exactly 988KB large, leaving 36KB for the VGA BIOS.
Skip this section if you use the LAB payload.
When using FILO in GRUB emulation mode, it's important to get a few details right in your GRUB boot stanza. This is what mine looks like:
title Ubuntu LB, kernel 2.6.21-rc3 root (hd4,0) kernel /boot/vmlinuz-2.6.21-rc3 root=/dev/sda1 ro console=tty0 console=ttyS0,115200 savedefault boot
Note the root device — FILO sees the first SATA device as hd4.
In order to get serial output from GRUB, you will also need to add something like this to your menu.lst:
# serial port 0 serial --unit=0 --speed=115200 terminal --timeout=15 serial console
Skip this section if you use the FILO payload.
The LAB payload expects a file /lab.conf on /dev/sda1 with contents like this:
CMDLINE="root=/dev/sda1 ro console=tty0 console=ttyS0,115200" KERNEL="/vmlinuz-188.8.131.52" INITRD="" VT="1"
This is the kernel that you will be running after boot. It will be kexec'ed by the kernel that is burned into your ROM chip.
You will also need a statically linked copy of kexec, which the LAB payload expects to reside at
If you are on a Debian-based system, you can easily recompile your kexec package to be statically linked by following these instructions:
cd /usr/src apt-get source kexec-tools export LDFLAGS="-static"
Now edit kexec-tools-1.101-kdump10/kexec-tools-1.101/kexec/Makefile, change line 53 to
$(CC) $(LDFLAGS) $(KCFLAGS) -o $@ $(KEXEC_OBJS) $(UTIL_LIB) $(LIBS)
(you're adding the LDFLAGS variable)
cd kexec-tools-1.101-kdump10 dpkg-buildpackage -rfakeroot -b cd .. dpkg -i kexec-tools_1.101-kdump10-2ubuntu2_i386.deb
Adjust the package name as necessary for your distribution. You can tell if your copy of kexec is statically linked by running 'file' on it:
If all is well, you will see something like this:
/sbin/kexec: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), for GNU/Linux 2.2.0, statically linked, for GNU/Linux 2.2.0, stripped
The binary will also be considerably larger than its dynamically linked cousin.
Note that you must build a 32-bit version of kexec, because buildrom puts a 32 bit kernel into the ROM image. A 32-bit kexec can kexec into a 64 bit kernel, so if your system is 64 bit this will work just fine.
The LAB code currently expects lab.conf and kexec to live in / on /dev/sda1.
Skip this section if you don't need VGA support in your coreboot.
The S2891 VGA BIOS is 36K long. The last 4KB are not available in RAM after boot (with the proprietary BIOS), however, so we can not use this method to extract the VGA BIOS:
While booted with your proprietary BIOS, you can see where your vga bios starts and how much space it takes by issuing
cat /proc/iomem | grep "Video ROM"Then get a copy of your vga bios.
dd if=/dev/mem of=vgabios.bin bs=1k count=32 skip=768Our vga bios is 32K. Verify that the image is correct - it should start with 55 AA, and contain strings that indicate it's your VGA bios. You should be able to clearly make out 'ATI RAGE' etc.
So this does not work - the last 4K is missing. Thankfully, Anton Borisov has some tools that can extract the VGA BIOS — and other option ROMs, in fact — from the BIOS images that Tyan offers on its website.
You can download the tool for Phoenix here:
Then download the latest proprietary BIOS for the S2891 from the Tyan website:
Once you have the image, you can display its contents like this:
./phnxdeco 2891202T.wph -ls
That should show output like:
-=PhoenixDeco, version 0.33 (Linux)=-
Filelength : 100756 (1050454 bytes) Filename : ../2891202T.wph PhoenixBIOS hook found at : F6FB0 System Information at : F6FFE BootBlock : 7000 bytes BankSize : 1024 KB Version : DEVEL042 Start : F8BB5 Offset : F0000 BCP Modules : 80 BCPFCP : FCA73 FCP 1st module : 9DD5 (F9DD5) Released : 30 November 2006 at 11:19:23 /* Copyrighted Information */ NAPI /* ----------------------- */ ================================== MODULE MAP ================================= Class Code . Instance . . C I LEVEL START END LENGTH RATIO LINK TO FILEOFFSET ---- ----- --------- --------- ------ ----- --------- ---------- G 0 NONE FFFF 8BB5 FFFF 8FFF 430 100% FFFF 8048 F8BB5h D 0 LZINT FFFF 8048 FFFF 8BB4 B52 70% FFFF 7FDB F8048h A 1 LZINT FFFF 7FDB FFFF 8047 52 70% FFFF 7FBC F7FDBh * 0 NONE FFFF 7FBC FFFF 7FDA 4 100% FFFF 7BA3 F7FBCh B 0 LZINT FFFF 7BA3 FFFF 7FBB 3FE 3% FFFF 0E05 F7BA3h X 0 NONE FFFF 0E05 FFFF 7BA1 6D82 100% FFFE C525 F0E05h S 0 LZINT FFFE C525 FFFF 0E04 48C5 46% FFFE 8601 EC525h E 0 LZINT FFFE 8601 FFFE C524 3F09 41% FFFE 65D5 E8601h C 0 NONE FFFE 65D5 FFFE 85FF 2010 100% FFFE 0005 E65D5h X 1 NONE FFFE 0005 FFFE 644F 6430 100% FFFD A653 E0005h T 0 LZINT FFFD A653 FFFE 0004 5997 42% FFFD 365C DA653h R 0 LZINT FFFD 365C FFFD A652 6FDC 58% FFFC DAC1 D365Ch R 1 LZINT FFFC DAC1 FFFD 365B 5B80 63% FFFB 9ED0 CDAC1h R 2 LZINT FFFB 9ED0 FFFC DAC0 13BD6 61% FFFA 73D5 B9ED0h R 3 LZINT FFFA 73D5 FFFB 9ECF 12AE0 98% FFF9 48E0 A73D5h R 4 LZINT FFF9 48E0 FFFA 73D4 12ADA 98% FFF8 B14D 948E0h R 5 LZINT FFF8 B14D FFF9 48DF 9778 59% FFF8 9830 8B14Dh L 0 LZINT FFF8 9830 FFF8 B14C 1902 0% FFF8 825D 89830h M 0 LZINT FFF8 825D FFF8 982F 15B8 64% FFF8 5C92 8825Dh Q 0 LZINT FFF8 5C92 FFF8 825C 25B0 41% FFF7 F3D7 85C92h H 0 NONE FFF7 F3D7 FFF8 5C91 68A0 100% FFF7 DDF1 7F3D7h A 0 LZINT FFF7 DDF1 FFF7 F3D6 15CB 38% FFF7 766B 7DDF1h B 1 LZINT FFF7 766B FFF7 8D91 170C 25% FFF6 F699 7766Bh B 2 LZINT FFF6 F699 FFF7 766A 7FB7 73% FFF6 5694 6F699h B 3 LZINT FFF6 5694 FFF6 F698 9FEA 67% FFF5 A1F3 65694h B 4 LZINT FFF5 A1F3 FFF6 5693 B486 71% FFF5 917A 5A1F3h B 5 LZINT FFF5 917A FFF5 A1F2 105E 68% FFF5 8477 5917Ah B 6 LZINT FFF5 8477 FFF5 9179 CE8 67% 0000 0000 58477h Total Sections: 28
Now extract all these parts:
./phnxdeco 2891202T.wph -xs
That will create a number of new files:
-rw-r--r-- 1 ward ward 14643 2007-06-20 15:16 ACPI0.rom -rw-r--r-- 1 ward ward 116 2007-06-20 15:16 ACPI1.rom -rw-r--r-- 1 ward ward 28672 2007-06-20 15:16 bb.rom -rw-r--r-- 1 ward ward 33913 2007-06-20 15:16 BIOSCOD0.rom -rw-r--r-- 1 ward ward 22987 2007-06-20 15:16 BIOSCOD1.rom -rw-r--r-- 1 ward ward 44635 2007-06-20 15:16 BIOSCOD2.rom -rw-r--r-- 1 ward ward 60875 2007-06-20 15:16 BIOSCOD3.rom -rw-r--r-- 1 ward ward 64891 2007-06-20 15:16 BIOSCOD4.rom -rw-r--r-- 1 ward ward 6123 2007-06-20 15:16 BIOSCOD5.rom -rw-r--r-- 1 ward ward 4907 2007-06-20 15:16 BIOSCOD6.rom -rw-r--r-- 1 ward ward 1099 2007-06-20 15:16 DECOMPC0.rom -rw-r--r-- 1 ward ward 4128 2007-06-20 15:16 DISPLAY0.rom -rw-r--r-- 1 ward ward 787512 2007-06-20 15:16 LOGO0.rom -rw-r--r-- 1 ward ward 8576 2007-06-20 15:16 MISER0.rom -rw-r--r-- 1 ward ward 49152 2007-06-20 15:16 OPROM0.rom -rw-r--r-- 1 ward ward 36864 2007-06-20 15:16 OPROM1.rom -rw-r--r-- 1 ward ward 131072 2007-06-20 15:16 OPROM2.rom -rw-r--r-- 1 ward ward 77824 2007-06-20 15:16 OPROM3.rom -rw-r--r-- 1 ward ward 77824 2007-06-20 15:16 OPROM4.rom -rw-r--r-- 1 ward ward 65536 2007-06-20 15:16 OPROM5.rom -rw-r--r-- 1 ward ward 28061 2007-06-20 15:16 ROMEXEC0.rom -rw-r--r-- 1 ward ward 25675 2007-06-20 15:16 ROMEXEC1.rom -rw-r--r-- 1 ward ward 1234 2007-06-20 15:16 rom.scr -rw-r--r-- 1 ward ward 39110 2007-06-20 15:16 SETUP0.rom -rw-r--r-- 1 ward ward 40396 2007-06-20 15:16 STRINGS0.rom -rw-r--r-- 1 ward ward 4 2007-06-20 15:16 TCPA_*0.rom -rw-r--r-- 1 ward ward 26784 2007-06-20 15:16 TCPA_H0.rom -rw-r--r-- 1 ward ward 23136 2007-06-20 15:16 TCPA_Q0.rom -rw-r--r-- 1 ward ward 53472 2007-06-20 15:16 TEMPLAT0.rom -rw-r--r-- 1 ward ward 8208 2007-06-20 15:16 UPDATE0.rom
After a bit of fun with 'strings', we can deduce that the OPROM1.rom file contains our VGA BIOS.
So, now that we have the proper VGA BIOS image (36K long), we need to concatenate the VGA BIOS with the coreboot image
cat OPROM1.rom tyan-s2891.rom > final_coreboot.rom
Burning the BIOS
Make sure your BiosSavior is set to the 'RD1' position (not to 'ORG'!), so that you can always revert to the original BIOS.
On the target machine:
cd coreboot-v2/util/flashrom ./flashrom -v -w path/to/your/final_coreboot.rom
If you want VGA support, make sure you burn the final_coreboot.rom image!
You now need to 'halt' the machine. A soft reset won't work the first time you boot from the proprietary BIOS into coreboot.
Since we set up serial output in the coreboot configuration files above, you will want to hook up a serial console (or a copy of minicom or the like) to see what the box is doing while starting up. Keep your eyes on the screen after hitting the power button - coreboot will be up and running way before you expect it!
If you have problems, don't despair. Power down the box, switch the BiosSavior to 'ORG' and boot in the proprietary BIOS. Just don't forget to switch the BiosSavior back to the 'RD1' position before flashing the BIOS!
See what went wrong, and subscribe and post to the friendly and helpful mailing list if you can't figure it out by yourself.
|This work is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or any later version. This work 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 the GNU General Public License for more details.|