[coreboot] SeaBIOS, serial output, and grub
ward at gnu.org
Thu May 21 22:11:38 CEST 2009
On Thu, May 21, 2009 at 01:03:30PM -0400, Ward Vandewege wrote:
> On Thu, May 21, 2009 at 12:13:04PM -0400, Ward Vandewege wrote:
> > 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!
> OK, I can now get to the boot menu, which is great.
> Ideally though, all output starting from 'Starting Seabios' would end up on
> serial as well as console. So, drive detection, gpxe being loaded, any other
> option roms being loaded.
> Is that at all possible? Perhaps seabios could treat an optionrom with name
> genroms/sgabios.rom as special and load it before all other option roms?
Perhaps somewhat related: there's a screen redrawing issue when using
sgabios. After sgabios loads, it resets the cursor position to the top of the
screen, which makes the rest of the output go on top of whatever was already
on the screen.
I suppose that if sgabios could be loaded much earlier - before 'Starting
SeaBIOS' is printed to the console, this would not be an issue.
Ward Vandewege <ward at fsf.org>
Free Software Foundation - Senior Systems Administrator
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