BIOS POST codes monitoring in real time from other computer

[Antonio Expósito]

Hi all,

I don’t want to disturb you with “newbie things”, but this is a way to start
like another.

I am trying to monitor the boot process of a computer, mainly BIOS POST
codes and linux kernel boot process. I know how to do it for the linux
kernel using a serial port, but I am not able to imagine how to monitor the
BIOS POST codes.

I know that almost every BIOS sends them to the ISA I/O address 0080h, but,
how can I get that codes using another computer? I mean,  without POST
ISA/PCI card, using another computer connected to it via SMBUS, LPC or
serial?

Is there any way to convert LPC to serial and monitor that port?

I want to do this with a VIA P700 motherboard, is this board supported by
the coreboot v3?

Could be easy to redirect BIOS POST codes to a serial port using a coreboot
implementation?

Thanks in advance,

Antonio

BIOS POST codes monitoring in real time from other computer

[Carl-Daniel Hailfinger]

Hi,

On 17.09.2009 21:13, Antonio Expósito wrote:
> I know that almost every BIOS sends them to the ISA I/O address 0080h, but,
> how can I get that codes using another computer? I mean,  without POST
> ISA/PCI card, using another computer connected to it via SMBUS, LPC or
> serial?

There are some POST cards which convert the POST codes to serial, but
they are really expensive (>50 EUR).
> Is there any way to convert LPC to serial and monitor that port?

You can convert LPC to usb-serial (a virtual serial device which appears
once you plug in the USB side into the monitoring computer) with the
Artec FlexyIce (formerly known as the Artec Dongle). The FlexyIce is
also usable as LPC/FWH ROM emulator and ideal for firmware/coreboot
development.
> Could be easy to redirect BIOS POST codes to a serial port using a coreboot
> implementation?

If you have coreboot, you don't need POST codes because you get detailed
messages (similar to Linux kernel messages) from coreboot on the serial
port.

Regards,
Carl-Daniel