On 21.05.2012, at 05:32, ron minnich rminnich@gmail.com wrote:
On Sun, May 20, 2012 at 1:23 AM, Kyösti Mälkki kyosti.malkki@gmail.com wrote:
Hi
I did not find this method of bypassing the mainboard flash chip and booting from PCI add-on card documented or discussed before.
Maybe I misunderstand, but this is how Etherboot originally worked: flash a new expansion rom onto, e.g., a 3c905 and that could take over the boot process.
If I read the original mail correctly, the method he describes maps the PCI card's option rom _over_ the mainboard one, so it allows for execution of code way earlier.
However, couldn't the normal option rom code path be used to configure the BAR to 0xfff... and trigger a triple fault, rebooting the machine automatically into coreboot? That way you wouldn't have to manually enable coreboot, but only need to have your special PCI card plugged in ;)
Alex