> What I'm asking is, can the hardware itself map the framebuffer (or
> whatever) into the address space,

Even good-old ISA cards were able to do so (ok only in the first 16 MB
of physical address space *G*). With PCI they became able to tell the
chipset about the size of their "card memory" and the memory controller
in the chipset will respect these in its internal memory mapping (and
tell it to the CPU (and the operating system) so the CPU will disable
its interlal L1 caches etc. for these address ranges etc.)

Just look at /proc/iomem to see how heterogenious the physical address
space is on modern computers.

The mmap() just maps portions of this physical address space into your
logical/program/user address space.

Lars R.

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