Re: [coreboot] Need confirmation if HP nx6310 will work with coreboot

Hi,

oh shit, I thought it would be sufficient to rewrite the flash chip on the board by flashrom! Why this effort?

Need confirmation if HP nx6310 will work with coreboot

[Carl-Daniel Hailfinger]

Hi,

On 07.04.2010 12:36, [e-mail] wrote:
> oh shit, I thought it would be sufficient to rewrite the flash chip on the board by flashrom! Why this effort?

Stefan's description was about the easy and optimal way to get coreboot
running. Depending on the embedded controller (EC) on your board, it is
easily possible you will spend a few weeks or even months full-time to
have coreboot working completely on your laptop.

Why is it such a big effort to port coreboot to a new board, especially
a laptop?
- An OS can simply probe for hardware and load the correct driver.
coreboot can't do that because some of the hardware has to be
initialized blindly (probing is impossible).
- Many board specific settings are not stored in the hardware and there
is no way to determine them from software. The firmware (coreboot/BIOS)
has to know them, or RAM/interrupts/DMA/... will not work. An OS
retrieves these settings from the firmware.
- For some of the hardware on laptops (usually the EC) there is no
documentation at all, so you can either leave the EC (which has its own
firmware) alone and try to reverse engineer the communication protocol
between EC and main CPU which will take weeks or months, or you can
write your own EC firmware which will take months with docs or years
without docs.
- It is not unusual to need a few dozen tries before coreboot runs well
enough on a board that you can reflash in-system.

Regards,
Carl-Daniel