Joe, Just a quick update. On Sun, 22 Sep 2013, Maciej W. Rozycki wrote: > As to the PMAG-AA board itself -- well, this is indeed a very rare item, > but I happen to have a specimen. To support it properly I'll first have > to wire it to a monitor somehow though; signalling is standard, 1.0 Vpp > composite monochrome, but what looks to me like a type F connector is used > for video output, quite unusually for a graphics card (and for DEC itself > too as 3W3 was their usual video socket). It looks to me like converting > it to BNC and then a standard DE-15 VGA connector (via the green line) > will be the easiest way to get image produced by the adapter on a > contemporary monitor (sync-on-green required of course, but with LCD > devices being the norm now that seems less of a problem these days). So more weirdly even that's actually a TNC connector rather than a type F one. I've got a suitable TNC->BNC adapter now (although regrettably such adapters seem to be available as 50Ω parts only; hopefully any distortion won't be too significant or maybe my digital monitor will even be able to compensate it, but at £1.76 (~$2.64) per item it's certainly worth trying before resorting to the original DEC TNC->BNC cable still apparently available from second-hand part suppliers at ~£80/$120 per a mere 1ft part) and a BNC->DE-15 cable is on the way. > > --- a/drivers/video/pmag-aa-fb.c > > +++ b/drivers/video/pmag-aa-fb.c > > @@ -459,7 +459,7 @@ static int __init init_one(int slot) > > return -EINVAL; > > > > printk(KERN_INFO "fb%d: %s frame buffer in TC slot %d\n", > > - GET_FB_IDX(ip->info.node), ip->info.modename, slot); > > + ip->info.node, ip->info.modename, slot); > > > > return 0; > > } > > Thanks, but the changes required are actually much more than that -- the > driver has never been converted to the modern TURBOchannel API. I have > now dug out an old patch I was working on back in 2006 to convert this > driver as well as drivers/video/maxinefb.c. I'll try to complete the two > drivers as soon as possible (unfortunately I can't test the latter at all; > it's for an onboard graphics adapter of another DECstation model), > although I now remember the main reason I didn't complete them back then > was they used an old internal API that was removed and no suitable > replacement provided. I need to investigate again what that actually was > though (hw cursor probably). So I think I've got all the basic stuff covered now, including a change similar to your proposal as well as a conversion to the driver model/new TURBOchannel support infrastructure. But what I remembered is actually right, the issue is wiring hardware cursor support into fbcon. The driver uses its own display_switch structure with its own aafbcon_cursor handler to use the twin onboard Bt431 chips for cursor generation (there's also aafbcon_set_font that pokes at the Bt431s for cursor dimension changes). I need to figure out what the best way will be to make the fbcon subsystem support such an arrangement and that'll take me a little bit yet, so please be patient. Note that the board is weird enough to have a 1-bit (true monochrome) graphics plane, however the Bt455 used by the MX graphics adapter for screen image generation is a 4-bit grey-scale video RAMDAC (only the LSB inputs of its pixel port are wired to the graphics plane) and the twin Bt431s use the overlay plane to produce a 2-bit grey-scale cursor. So we do want to use the hardware cursor to be able to make it prominent among the characters displayed throughout the screen and a software-generated cursor cannot really substitute what hardware provides. Maciej
