Re: Switching to Xorg

[der Mouse <mouse%Rodents.Montreal.QC.CA@localhost>]

> If X wants to access a PCI graphics board it currently needs to be
> the console. Part of the reason is that - unlike many 32bit machines
> - PCI bus addresses don't coincide with their physical addresses from
> the CPU's point of view, the console driver hides that from the
> Xserver so it can mmap PCI resources with their bus addresses, but
> only for the console.

Surely the right thing to do is to fix the framebuffer drivers so mmap
works on them without their having to be console?

> Also, the physical address of the PCI address space depends on the
> machine and to make things more complicated some Ultras have more
> than one PCI bus.

None of which should matter; that's what the framebuffer driver is for:
to present a uniform interface to application code, regardless of the
underlying resources.

> Before you ask - none of this is different with Xorg, it may change
> with their next major release if someone ports libpciaccess to
> NetBSD.

Better would be to fix the (severley) broken paradigm that has the X
server knowing anything about buses.  The X server should be using a
uniform interface presented by the framebuffer driver, independent of
the underlying bus(s) (if any) - that's what drivers are *for*!  (It
works fine that way on sparc32....)

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