Re: XFree86 4.1.0: call for help
On Fri, 1 Jun 2001, Ani Joshi wrote:
> On Sat, 2 Jun 2001, Michel [ISO-8859-1] Dänzer wrote:
> > I might do that, but then is there any benefit of vgaHW working on a Mac? It
> > seems to work fine without, so I might as well hack the syscall to fail.
>
> Yes, vgaHW is very much indeed needed on Mac (or pretty much any
> platform). For boards with a VGA core which doesn't have its VGA
> registers mirrored in (MM)IO space, this is the only way to setup a mode.
> Since PPC doesn't have "normal" ISA IO space (0x0 - 0xffff), we map the
> ISAio region (usually first 0xffff off the pciBase, unfortunately some
> machines have many pciBases, which is the problem ofcourse), this giving
> the various port IO (inb/outb,etc.) consistent functionality with i386.
>
> While few of these boards are used on PPC (voodoo3 was the main reason why
> I added ISA IO support for ppc in X, but apparently there is new evidence
> that voodoo3 does indeed have vga regs in MMIO), it is still necessary to
> have this functionality for other boards (mostly all old boards like the
> S3 chipsets, ARK, and many others can only set VGA regs by PIO).
AFAIK `sufficiently new'[*] S3 chips power up in MMIO mode.
[*] All PCI chips starting with S3Trio64V+, Vision868/968, and the various
ViRGEs. The Vision864/964, and probably the original Trio32/64 as well,
power up in legacy mode (not to mention old ISA/VLB chips we don't care
about).
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@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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