martin@duskware.de wrote:

> > It looks only SGIMIPS_BUS_SPACE_IO and SGIMIPS_BUS_SPACE_MEM
> > require byteswapping on stream ops.
> 
> Ok - like this?

IMHO, calling bus_space_{read,write}_N() from stream functions
might cause significant overhead (especially on region/multi ops
used for PIO xfers), so it maybe better to have independent stream
read/write functions which are mostly identical with normal
bus_space_{read,write}_N() ops but different for
SGIMIPS_BUS_SPACE_{IO,MEM} tags.

Ideally, it's much better to switch sgimips bus_space tag structure
to use function pointer based one (like alpha or dreamcast etc.,
and already defined in <mips/bus_space.h>), but it depends on
your motivation ;-)
---
Izumi Tsutsui