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
need to explicitly relatch the interrupt when firing it up again. So, in the
trigger routines, explicitly disable and reenable the interrupt to relatch it,
like we do in the interrupt routine.
Also clean up some broken loop overrun checks.
My ES1371 seems to be more reliable now, but I'm not going to pretend to fully
understand this chip.
to be cleared always in edmcadone(), otherwise if there is a write
via bounce buffer followed by read directly to buf, the read operation
would return trashed data (the buf data would get overwritten
by contents of bounce buffer in edmcadone()).
Reset b_resid as necessary when the i/o is done, too.
g/c some unneeded stuff, use lockmgr()-style locking in ed_[un]lock(),
better avoid some deadlocks
These changes make the driver quite a bit more stable. It's actually
reliable enough to be possible to newfs the drive and use it for
read/write filesystem now.
XXX Currently disabled by default because it has some problems on macppc.
XXX Maybe some more initialization is needed, but there is few information
XXX about the chips.
resulting in a blank screen when f.e. a setcursor ioctl was called
after the screenblanker had enabled the screen again ... the actual
switching on was then never performed at VSYNC.
A simple |= instead of = does the trick ... just leave the other bits
on please :)
Tested with NE/2 card provided to me by Hans Hubner <hans@Huebner.ORG>.
The Compex and Arco cards were not tested. According to Linux ne2 driver,
they should work same way as NE/2.
Disk & Controller only at the moment.
This driver still needs some touchup (error recovery is not quite
good, MCA DMA controller goo should be moved to driver independant
location), but is working enough to be usable for others. And I
want this under CVS control :)
Thanks to Scott Telford <st@epcc.ed.ac.uk> for providing me docs for
these devices (IBM DASD Storage Interface Specification for MCA rev. 2.2).
kleink