ADMtek AL981 "Comet" chipset. The AL981 is yet another DEC tulip clone,
except with simpler receive filter options. The AL981 has a built-in
transceiver, power management support, wake on LAN and flow control.
This chip performs extremely well; it's on par with the ASIX chipset
in terms of speed, which is pretty good (it can do 11.5MB/sec with TCP
easily).
I would have committed this driver sooner, except I ran into one problem
with the AL981 that required a workaround. When the chip is transmitting
at full speed, it will sometimes wedge if you queue a series of packets
that wrap from the end of the transmit descriptor list back to the
beginning. I can't explain why this happens, and none of the other tulip
clones behave this way. The workaround this is to just watch for the end
of the transmit ring and make sure that al_start() breaks out of its
packet queuing loop and waiting until the current batch of transmissions
completes before wrapping back to the start of the ring. Fortunately, this
does not significantly impact transmit performance.
This is one of those things that takes weeks of analysis just to come
up with two or three lines of code changes.
Implement priorities.
GENERIC, LINT, files:
Remove remarks about ordering of device names.
GENERIC, LINT:
Sort the devices alphabetically in LINT and GENERIC.
The specific intent of this commit is to pave the way for importing
Compaq XP1000 support. These changes should not affect the i386 port.
Reviewed by: Doug Rabson <dfr@nlsystems.com>
(actually, he walked me through most of it & deserves more than reviewd-by
credit )
Fixed problems:
LS120/ZIP drives still currupted data.
Reworked once again, buffered I/O is just ignoring any sizehints
it is given :(
Now the atapifd driver splits up requests for devices that has
limitted transfer size.
ISA only configs fails on boot with interrupt timeouts.
The new-bus integration introduced a bug where the softc ptr
was lost during the probe.
Some minor cleanups and rearrangements as well.
As usual USE AT YOUR OWN RISK!!, this is still pre alpha level code.
Especially the DMA support can hose your disk real bad if anything
goes wrong, again you have been warned :)
Notebook owners should be carefull that their machines dont suspend
as this might cause trouble...
But please tell me how it works for you!
Enjoy!
