Don't mess with the IRQMS bit in the host control register unless
we are an aic7770 chip.
Use calling context to determine if the card is already paused when
we update the target message request bit field in controller scratch
ram. Looking at the paused bit in the HCNTRL register opened up a
race condition.
Insert delays in the target message request update routine as a temporary
work around for what looks like a chip bug. I'm still investigating this
one.
Fix the Abort/Abort Tag/BDR handler to pull its message from the message
buffer in our softc instead of attempting to get it from a register on
the controller. The message is never recorded by the controller in the
new message scheme.
Don't rely on having an SCB when a BDR occurs. We can issue these during
invalid reconnects to.
Fix a few cases where we were restarting the sequencer but then still
falling out of a switch statement to unpause the sequencer again.
This could cause us to mess up sequencer state if it generated another
pausing interrupt between the time of the restart and unpause.
Kill the 'transceiver settle' loop during card initialization. I
failed to realize that a controller that is not connected to any
cables will never settle or enable the SCSI transceivers at all.
The correct solution is to monitor the IOERR interrupt which indicates
that the transceiver state has changed (UW<->LVD).
Modify the aic7xxx assembler to properly echo input when stdin is not
a tty.