> On Wed, Jan 14, 1998 at 04:56:38PM -0800, William J. Earl wrote:
> > > Thinking about it, the kernel should only try to touch the gfx hardware
> > > at all, if the ARC environment variable ``console'' is unset. If you
> > > want to run from a serial console, then the variable's value should be
> > > either ``d1'' or ``d2'' for the first rsp. second serial interface.
> > > I suppose IRIX just defaults to serial console because it knows that
> > > a Challenge S is headless or after a failed probe for gfx hardware.
> > IRIX probes for the graphics card. If the probe fails, it
> > assumes this is not one. If there is no graphics, or if console != g,
> > it sets the system console to the serial port. Note, however, that
> > IRIX normally puts up an X login on the graphics head even if
> > console=d and thus the console is on the serial port. This seems
> > like a reasonable approach for linux as well.
> Indeed, this is how Linux will behave after the probe / console env
> thing is fixed. I assume your more than minimal necessary probe has the
> purpose to make shut that the machine does not only have gfx but also
> that the gfx found in the address space is not something else like the
> XZ for example?
Yes, that is correct. Also, it means that the system will
come up with a serial console if the graphics board is completely dead.