sgimips o2 and ARCS console in video mode hangs when it scrolls

hi!

here's a fun regression. NetBSD boots and runs fine on my R5000SC-180
O2, but only with a serial console. If it decides to use the video
console, then it hangs the moment the ARC console scrolls.

This is happening way before the framebuffer driver is being called.
If I put a while(1) printf() loop in mach_init(), just after
arcbios_init(), it still happens.

It's fine on a serial console - even the crm driver finds the attached
monitor that the firmware detect and initialised and will happily be
ready to display stuff.

So, does anyone have any memories of when O2 + graphical console last
worked? A lot has changed in the arcbios code and the calling
convention stuff and I'd like to establish if this /did/ work at some
point or (if Michael pointed out in a private email thread) we used to
get far enough in boot to bring up the crm driver to kick over to the
native console code before we caused arcbios to scroll.

Thanks!



-adrian