Basically it does a timeout on lost interrupts, starting the operation
again and logging and error message on the console.
additionally fixes some of the (newer ending) while loops
(that made it work with two IDE disks !)
1. controller reset code moved into one function, called from more places now.
2. more places now do timeouts. TIPCAT code turned on.
3. blew away the unused WDOPENLOCK test code.
4. delay is now done using WDCNDELAY repetitions of DELAY(25). Up to 2.5 second
pause accepted from controller (some controllers have some commands that are
actually this slow)
5. some of the old timeout code was really whacked.
WD1007-derived controllers. In this example, wdc0 is a WD1007-clone,
and wdc1 is a WD1003-clone. WD1007 controllers are generally ESDI
and IDE controllers.
wdc0 at 0x1f0-0x1f7 irq 14 on isa
wd0 at wdc0 targ 0: 322MB 1224 cyl, 15 head, 36 sec <disktype>
wdc1 at 0x170-0x17f irq 7 on isa
wd2 at wdc1 targ 0: (unknown size) <disktype>
devices hanging off controllers, any kind of controller.
A device on isa0 is called at probe(self), then attach(self)
A controller on isa0 is called at probe(self), then all it's children with
defined unit numbers are initialized by calling attach(subdev); next all
subdevices with unit ? are initialized by calling attach(sundev).
Almost all device entry points is now like the vax/sun model (intr being
the weird one)
controllers. New behaviour is that if the standard method fails, try
to recalibrate the drive. Success means the drive exists. patch by
hpeyerl@novatel.cuc.ab.ca (who owns several of these historical
artifacts)
