[coreboot] SeaBIOS, serial output, and grub

Ward Vandewege ward at gnu.org
Thu May 21 18:13:04 CEST 2009

On Fri, May 15, 2009 at 10:37:56PM -0400, Kevin O'Connor wrote:
> On Fri, May 15, 2009 at 11:27:35AM -0400, Ward Vandewege wrote:
> > Now - the reason why I wanted to use sgabios, was to get the seabios console
> > output on serial.
> > 
> > As you can see in the logs, sgabios is loaded too late to be much use for
> > that (after the disk detection, and after seabios prints 'Press F12 for boot
> > menu').
> > 
> > If sgabios is the way to get seabios to copy console to serial, would it be
> > possible to load the sgabios option rom (much) earlier?
> Sgabios isn't a PnP rom, and it therefore doesn't get called before
> the boot menu.  You can try the patch to sgabios below - I don't know
> how reliable it will be.

That worked! However, the serial bug is apparently back - grub's printing
'Press any key to continue' very very slowly, and ignoring serial console
input while that is happening. See boot log at:


Once grub gets to the 'press esc for menu' countdown, serial console works


Ward Vandewege <ward at fsf.org>
Free Software Foundation - Senior Systems Administrator

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