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
re-enqueueing an already free ccb.
Prepare the background to have a unique initialization function for
all of the supported host adapters.
Rename a lot of #define in a more sane way.
Move Carriers initialization and defines in adwmcode.{c,h}
Don't lose Carrier nodes in case of a BUS/Chip reset explicitly invoked
after a DMA failure.
XXX - DMA failure still arise when AdvanSys U[2]W host adapters are used
in conjunction with Intel 82443BX Host Bridge/Controller (rev. 0x03).
!?!Have to understand why!?!
Add a way to instruct the upper layer to don't bother w/ new requests if/when a device queue is full/busy or the device is unavailabale at that time
Use scsipi_inquiry_data instead of its own inquiry structure
Add a catch for DMA Error which show up on Intel 82443BX Host Bridge/Controller (rev. 0x03). This doesn't fix the problem, but reset the SCSI bus and reinitialize the host adapter
Minor cosmetical changes
Thanks a lot to Greg Oster and Andan Lauber
Increased ADW_MAX_CCB to 63 and ADW_MAX_CARRIER to 253
Print WDTR/SDTR negotiation result per target
Protect AdvISR() inside splbio()/splx() pair
Add a pending queue to keep track of all the CCBs that are being executed by the host adapter.
Rewrote timeout handler in a more efficient way:
After 3 timeout now the SCSI is resetted and all pending queues not completed are now reenqueued in the waiting queue so to get executed just after the BUS Reset (hoping that resetting the SCSI BUS and reinitializing the adapter could solve the problem).
Fix minor glitches.
Add preliminary support for ASB-3940U3W host adapters; it might work w/ autotermination on.
ASB-3940U3W support is not yet tested due to lack of board.
