Re: [NILO-discuss] Zen and the art of running in real mode

[H. P. A. <hp...@zy...>]

Michael Brown wrote:
> 
> Sadly not.  Dedicated I/O space is a legacy x86 feature; in order to work 
> in non-x86 machines, hardware needs to support memory-mapped I/O.  Since 
> x86 can also use memory-mapped I/O (unless, of course, you're stuck in 
> real-mode), there's no real benefit to supporting it.  Hence, newer cards 
> are likely to be MMIO-only.
> 

There are two more reasons for this:

a) IOIO is only available in 256-byte chunks due to ISA address space 
braindamage;
b) On x86, IOIO is *SLOW* due mostly to the SMI virtualization support.

	-hpa