write operations appear to lose scsi interrupts and causes timeouts.
changes in this checkin include:
a nextdma bugfix causing a diagnostic check to erroneously trigger
Changed tail strategy to only use tail buffer for the minimal end slop
changed expected write dma overrun to 32 bytes.
turned on nextdma diagnostic check for dma end address since it
no longer gets triggerred by ethernet dma and helps debug scsi dma.
Added esp debugging printout and support.
a filesystem, but is not stable enough yet for general use.
increased priority of ethernet interrupts, mostly useful to aid debugging
of scsi interrupts while using an nfs disk.
added additional debugging output in the next dma driver.
perform extranneous cache flushes/purges before dma reads/ after dma writes
to aid debugging of scsi dma.
it still probes the disks ok, but is having trouble with 0xdeadbeef
in buffers read from the disk. Suspected problems with DMA alignment
and toggling the secret ninja dma control register