Xfree86-4.0.1, Lombard, Mach64 driver, X-server Crash

[Geert Uytterhoeven]

On Wed, 27 Sep 2000, Takashi Oe wrote:
> On Wed, 27 Sep 2000, Benjamin Herrenschmidt wrote:
> > >Here's a copy of my XF86Config file.
> > >Two other minor nuisances:
> > >
> > >Since using yaboot, my console cursor has disappeared. Is this an OF or a
> > >yaboot problem? It's very hard to navigate in vi to edit anything (.config
> > >files for one thing) without a cursor!
> >
> > Completely ? Or does it appear with different colors depending on the VC
> > you are on ? I've seen such bug appear here or there but never took the
> > time to track it down...
> >
> > I suspect an atyfb problem ;)
>
> I think this is more of a generic fb device layer problem or a combination
> of driver bug and upper layer bug.  Or I totally don't understand how
> fbcon works.
>
> My understanding is this:
> Video console uses 16 colors, and it only initializes the cmap
> corresponding to those 16 colors.  The other entries in cmap are up to
> each individual fb driver or undefined as far as console is concerned.
> For software cursor, driver specific (struct display_switch *)ops->revc()
> is used to make the cursor blink.  For the generic fbcon_cfb{16,32}_revc,
> it xors each pixel with masks 0xffff (depth 16) or 0xffffffff (depth 32).
> For controlfb which I am very familiar with, the "correct" masks are
> 0x3def for 555 and 0x0f0f0f0f for 8888.  That is, only 4 LSBs or low 16
> for each red, green, and blue are xor'ed since cmap entries corresponding
> to higher bits are undefined as far as fbcon support is concerned.

In 2.5.x, we'll have a user-defined xor mask for the cursor as the 17th entry
in the dispsw_data array.

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds


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