Hi,

Attached patch implements DMA support to RC4030 chipset and simplifies 
jazz IO part (at 0xf0000000), where registers contain 16 bit values.
Config register has not a clear meaning (only one value is always valid, 
and sometimes another one), so use a magic value instead.
The patch also wires DMA transfers for the SCSI adapter in the Jazz 
emulation (Mips Magnum 4000 and Acer Pica 61).

Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>

Changes since v1:
- Support reuse of esp callback functions up to DMA engine
- Don't keep in memory the DMA table, but read it when needed

Changes since v2:
- Don't use cpu_single_env in the DMA transfer function, as it is NULL 
in the aio path
- Multiple improvements to the DMA transfer function: report errors to 
the caller, support for non contiguous physical pages...

Changes since v3:
- Mask out higher bits of DMA translation table address

Changes since v4:
- Fix warnings on 64 bit hosts
- Document a change on the config register

Hervé