"XXX Maxphys temporary changed to 32K while SCSI driver is fixed."
I (and soda) don't know what the "SCSI driver" is, but add local
asc_minphys() to limit max xfer size only for asc.c for now.
- According to old asc.c driver, DMA_START() is called before NCR_CMD_DMA
command. I'm not sure which DMAC or ASC should be started first, but
move DMA command from asc_dma_go() to asc_dma_setup().
- Disable NCR_F_DMASELECT (which allows DMA xfer for select command)
since it caused some problem on PICA.
Now gxemul-0.3.6.2 reaches mountroot() sd0 (but can't exec /sbin/init yet).
This is a completely rewritten scsipi_xfer execution engine, and the
associated changes to HBA drivers. Overview of changes & features:
- All xfers are queued in the mid-layer, rather than doing so in an
ad-hoc fashion in individual adapter drivers.
- Adapter/channel resource management in the mid-layer, avoids even trying
to start running an xfer if the adapter/channel doesn't have the resources.
- Better communication between the mid-layer and the adapters.
- Asynchronous event notification mechanism from adapter to mid-layer and
peripherals.
- Better peripheral queue management: freeze/thaw, sorted requeueing during
recovery, etc.
- Clean separation of peripherals, adapters, and adapter channels (no more
scsipi_link).
- Kernel thread for each scsipi_channel makes error recovery much easier
(no more dealing with interrupt context when recovering from an error).
- Mid-layer support for tagged queueing: commands can have the tag type
set explicitly, tag IDs are allocated in the mid-layer (thus eliminating
the need to use buggy tag ID allocation schemes in many adapter drivers).
- support for QUEUE FULL and CHECK CONDITION status in mid-layer; the command
will be requeued, or a REQUEST SENSE will be sent as appropriate.
Just before the merge syssrc has been tagged with thorpej_scsipi_beforemerge
