configuration of devices logically attached to the ISA bus:
* Change the isa_attach_args to have arrays of io, mem, irq, drq
resources.
* Add a "pnpnames" and a linked list of "pnpcompatnames" to the
isa_attach_args. If either of these members are non-NULL,
direct configuration of the bus is being performed. Add an
ISA_DIRECT_CONFIG() macro to test for this.
* Drivers are not allowed to modify the isa_attach_args unless
direct configuration is not being performed and the probe fucntion
is returning success.
* Adapt device drivers -- currently, all driver probe routines return
"no match" if ISA_DIRECT_CONFIG() evaluates to true.
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
