Board:asus/p5gc-mx

This page describes how to use coreboot on the Asus p5gc-mx 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_ASUS=y
CONFIG_BOARD_ASUS_P5GC_MX=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 ASUS and the Mainboard model to P5GC-MX.

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 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 8MB. 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>

The VGA shared RAM can be increased to 16MB, 32MB or 64MB by running:

<syntaxhighlight lang="bash" inline>./nvramtool -C build/coreboot.rom -w gfx_uma_size=16M</syntaxhighlight> or <syntaxhighlight lang="bash" inline>./nvramtool -C build/coreboot.rom -w gfx_uma_size=32M</syntaxhighlight> or <syntaxhighlight lang="bash" inline>./nvramtool -C build/coreboot.rom -w gfx_uma_size=64M</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.

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

Internal flashing

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

External flashing

This board has a socketed DIP8 chip, so you can use - for instance - a CH341A to flash it.

Status (as of commit 5bb27b7815)

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 up to 1067MHz FSB. Pentium 4-like CPUs don'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	Quad cores are not supported by the chipset.
Hardware virtualization	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | Untested
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
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 }}" | N/A
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 }}" | Untested
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	VBIOS works. Only textmode available for native graphic init.
On-board Ethernet	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | OK
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 }}" | N/A
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
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 }}" | Untested
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 }}" | N/A
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
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 }}" | Unknown
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 }}" | Unkown
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 }}" | Unknown
Wake on LAN	OK=lime | TODO=red | No=red | WIP=orange | Untested=yellow | N/A=lightgray | yellow }}" | Unknown
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. Has a DIP8 socket.

Peculiarities

Normally on boards with an LGA755 socket the FSB multiplier is determined by 3 pins/straps on the CPU called BSEL. On this board those pins on the CPU are not hooked up to the memory controller, but some GPIOs on the SuperIO are used instead. The result is that to set up the correct FSB the SuperIO needs to be configured and then the system reset. Since this reset takes a few seconds, the fans will spin up, than spin down again to resume a full boot a few seconds later.

Variants

• The P5GC-MX/1333 might work just fine with the current code. The P5GC-MX/1333 vendor bios works fine on P5GC-MX but does not configure the SuperIO GPIO BSEL straps correctly which might indicate that it does not have those.
• P5GC-MX/GBL ?