Re: XFree86 4.1.0: call for help
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).
As Kostas pointed out, an efficent method to deal with the many buses of
some Apple machines will have to be worked out in the future.
ani
Reply to: