Well it's not just PCI that's interesting, I have this problem with
the ISA-bus on Amiga.  I've solved it by extending the bus.h interface
locally with the following functions:

u_int16_t bus_to_host_2(bus_chipset_tag_t, u_int16_t)
u_int32_t bus_to_host_4(bus_chipset_tag_t, u_int32_t)
u_int64_t bus_to_host_8(bus_chipset_tag_t, u_int64_t)

and

u_int16_t bus_to_host_2(bus_chipset_tag_t, u_int16_t)
u_int32_t bus_to_host_4(bus_chipset_tag_t, u_int32_t)
u_int64_t bus_to_host_8(bus_chipset_tag_t, u_int64_t)

These are only needed when you copy in structures as raw chunks and
need to convert on a field by field basis.  When dealing with moving
multibyte entitys directly to/from I/O space or memory, the possible
swapping is encapsulated in the bus_{io,mem}_{read,write}_[1248]
functions.

Niklas

Niklas Hallqvist       Phone: +46-(0)31-40 75 00  Home: +46-(0)31-41 93 95
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