Board:gigabyte/ga-g41m-es2l

This page describes how to use coreboot on the Gigabyte ga-g41m-es2l mainboard.

SeaBIOS ATA DMA

By default, SeaBIOS uses PIO mode for ATA interfaces. On the ICH7 southbridge, this is very slow. Loading a kernel + initramfs can take up to 20 seconds on this board.

When using ATA DMA mode, this bug disappears. This will have to be set explicitly in the SeaBIOS config file, and selected from coreboot's menuconfig.

From the coreboot root directory, go to payloads/external/SeaBIOS/seabios: <syntaxhighlight lang="bash" inline>cd payloads/external/SeaBIOS/seabios/</syntaxhighlight>

Create a file called .config and add these lines to it:

CONFIG_COREBOOT=y
CONFIG_ATA_DMA=y
CONFIG_VGA_COREBOOT=y

Then, create a full .config file by running: <syntaxhighlight lang="bash" inline>make menuconfig</syntaxhighlight>

Navigate to General Features and make sure the Build Target is set to Build for coreboot.

Navigate to Hardware support and make sure that ATA DMA is enabled [*].

Navigate to VGA ROM and make sure that VGA Hardware Type is set to coreboot linear framebuffer.

Exit menuconfig and save the changes.

It is probably easiest to move the .config file to the coreboot root directory, under a different name (e.g. .seabiosconfig), as coreboot already has its own .config file. <syntaxhighlight lang="bash" inline>mv .config ../../../../.seabiosconfig</syntaxhighlight>

Finally return to the coreboot root directory: <syntaxhighlight lang="bash" inline>cd ../../../../</syntaxhighlight>

coreboot configuration

Create a file called .config and add at least these lines to it:

CONFIG_VENDOR_GIGABYTE=y
CONFIG_BOARD_GIGABYTE_GA_G41M_ES2L=y
CONFIG_MAINBOARD_DO_NATIVE_VGA_INIT=y
CONFIG_USE_OPTION_TABLE=y

In case you do not want CPU microcode updates included in your ROM, add this line:

CONFIG_CPU_MICROCODE_CBFS_NONE=y

In case you do want to include CPU microcode updates in your ROM, add these lines:

CONFIG_USE_BLOBS=y
CONFIG_CPU_MICROCODE_CBFS_GENERATE=y

By default, serial debugging output is enabled. It is very useful for debugging, but also slows down the boot process a lot. If you don't need serial debug or have no idea how to use it, disable it:

CONFIG_CONSOLE_SERIAL=n

Then, create a full .config file by running: <syntaxhighlight lang="bash" inline>make menuconfig</syntaxhighlight>

Navigate to General setup and make sure that Use CMOS for configuration values is enabled [*].

Navigate to Mainboard and make sure the Mainboard vendor is set to GIGABYTE and the Mainboard model to GA-G41M-ES2L.

Navigate to Chipset and make sure that Include CPU microcode in CBFS is set to either Generate from tree or Do not include microcode updates.

• In case you selected Generate from tree, make sure that General setup -> Allow use of binary-only repository is enabled [*].

Navigate to Devices and make sure that Use native graphics initialization is enabled [*].

Navigate to Generic Drivers and set your ethernet MAC address in Realtek rt8168 mac address.

• You can retrieve your MAC address either from your OS when running the vendor BIOS (with ifconfig -a for instance), or from the white label on the ethernet port.

Navigate to Payload and set your SeaBIOS configuration in SeaBIOS config file.

• This requires a full path. For instance, if your coreboot root directory is in ~/Downloads, set ~/Downloads/coreboot/.seabiosconfig

Exit menuconfig and save the changes.

Now build your ROM: <syntaxhighlight lang="bash" inline>make</syntaxhighlight>

CMOS default values

By default, the VGA shared RAM on this board is set to 64MB, and the power on after fail option is enabled. While this is fine for server use, this is not ideal for desktop or HTPC use.

In order to change CMOS defaults, you will need nvramtool: <syntaxhighlight lang="bash" inline>cd util/nvramtool/ make mv nvramtool ../../nvramtool cd ../../ </syntaxhighlight>

Power on after fail can be disabled by running: <syntaxhighlight lang="bash" inline>./nvramtool -C build/coreboot.rom -w power_on_after_fail=Disable</syntaxhighlight>

The VGA shared RAM can be increased to 128MB, 256MB or 352MB by running:

<syntaxhighlight lang="bash" inline>./nvramtool -C build/coreboot.rom -w gfx_uma_size=128M</syntaxhighlight> or <syntaxhighlight lang="bash" inline>./nvramtool -C build/coreboot.rom -w gfx_uma_size=256M</syntaxhighlight> or <syntaxhighlight lang="bash" inline>./nvramtool -C build/coreboot.rom -w gfx_uma_size=352M</syntaxhighlight>

Backing up the vendor BIOS

This board can be flashed from the vendor BIOS with flashrom, which is in the repositories of nearly every GNU/Linux distribution.

It has two chips, which is supported by flashrom's dualbiosindex option. It is recommended to use at least flashrom 0.9.7 because support for this feature is buggy in older releases.

To make a backup of the main BIOS chip, run: <syntaxhighlight lang="bash" inline>sudo flashrom -p internal:dualbiosindex=0 -r m_bios.rom</syntaxhighlight>

To make a backup of the backup BIOS chip, run: <syntaxhighlight lang="bash" inline>sudo flashrom -p internal:dualbiosindex=1 -r b_bios.rom</syntaxhighlight>

Internal flashing

As coreboot does not support Gigabyte's DualBIOS feature, only the M_BIOS chip has to be flashed. The B_BIOS chip can safely be erased.

To erase the backup BIOS chip, run: <syntaxhighlight lang="bash" inline>sudo flashrom -p internal:dualbiosindex=1 -E</syntaxhighlight>

To flash the main BIOS chip, run: <syntaxhighlight lang="bash" inline>sudo flashrom -p internal:dualbiosindex=0 -w build/coreboot.rom</syntaxhighlight>

External flashing

This board is rather hard to flash, because powering the Vcc pin on the flash chip also powers the southbridge, causing a voltage drop likely resulting in errors reading, writing and verifying the chip.

It has been found that this can be worked around by powering up the board normally (even if it doesn't boot) and then shutting it down by holding the power button for 5 seconds (or by shorting the according pins). Then connect your SPI flasher (Vcc too!) and proceed as usual.

As stated above: only M_BIOS has to be flashed. B_BIOS can simply be erased. (Or flashed as well, but that won't make a difference.)

Chip pinout

      B_BIOS                     M_BIOS
 _______________
-cs   o      vcc-           -vcc---clk-mosi-
-miso           -           |              |
-            clk-           |              |
-gnd        mosi-           |  o           |
 _______________            -cs--miso---gnd-

Status (as of commit 5360c7ef94)

Device/functionality	Status	Comments
CPU
CPU works	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK	Core 2 Duo/Quad up to 1333MHz FSB. Modded LGA771 Xeons included. Pentium 4/D won't boot.
L1 cache enabled	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
L2 cache enabled	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
L3 cache enabled	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Multiple CPU support	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Multi-core support	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
Hardware virtualization	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
RAM
EDO	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
SDRAM	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
SO-DIMM	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
DDR	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
DDR2	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK	PC2-5300 CAS 5, PC2-6400 CAS 6 and PC2-6400 CAS 5 tested.
DDR3	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Dual channel support	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
ECC support	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
On-board Hardware
On-board IDE 3.5"	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
On-board IDE 2.5"	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | Untested
On-board SATA	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
On-board SCSI	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
On-board USB	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
On-board VGA	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
On-board Ethernet	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK	Requires file in CBFS to keep the proper MAC address.
On-board Audio	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
On-board Modem	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
On-board FireWire	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
On-board Smartcard reader	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
On-board CompactFlash	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
On-board PCMCIA	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
On-board Wifi	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
On-board Bluetooth	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
On-board SD card reader	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Add-on slots/cards
ISA add-on cards	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Audio/Modem-Riser (AMR/CNR) cards	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
PCI add-on cards	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
Mini-PCI add-on cards	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Mini-PCI-Express add-on cards	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | Unknown
PCI-X add-on cards	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
AGP graphics cards	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
PCI Express x1 add-on cards	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | Untested
PCI Express x2 add-on cards	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
PCI Express x4 add-on cards	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
PCI Express x8 add-on cards	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
PCI Express x16 add-on cards	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK	SDVO/ADD2 cards also work fine.
PCI Express x32 add-on cards	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
HTX add-on cards	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Legacy / Super I/O
Floppy	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | Untested
Serial port 1 (COM1)	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
Serial port 2 (COM2)	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Parallel port	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | Untested
PS/2 keyboard	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
PS/2 mouse	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | Untested
Game port	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Infrared	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
PC speaker	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
DiskOnChip	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Input
Trackpoint	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Touchpad	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Fn Hotkeys	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Fingerprint Reader	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Laptop
Docking VGA	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Docking LAN	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Docking USB	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Docking Audio	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Docking Displayport	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Thinklight	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Webcam	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Miscellaneous
Sensors / fan control	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK	Fan speed seems fixed. In practice, this is not a problem.
Hardware watchdog	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | Unknown
SMBus	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
CAN bus	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
CPU frequency scaling	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
Other powersaving features	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
ACPI	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
Reboot	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
Poweroff	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
Suspend	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
Nonstandard LEDs	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
High precision event timers (HPET)	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
Random number generator (RNG)	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Wake on modem ring	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | N/A
Wake on LAN	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
Wake on keyboard	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | Unknown
Wake on mouse	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | Unknown
TPM	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | Unknown
Flashrom	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK	Can be flashed from vendor BIOS, with -p internal:dualbiosindex=0/1. Chip 1 can safely be erased with -E.