I'd like to axe some drivers
John Baldwin
jhb at freebsd.org
Thu Nov 20 21:32:32 UTC 2014
I'm >< close to removing timeout/untimeout from the tree. As part of this I
have updated several older drivers to use callout(9), but most of those
patches were untested. Keeping old code around that no one uses does add
future work as tree-wide API changes are made as well as things like locking
(note that several of these drivers weren't locked until I recently changed
them). To that end, here is my short list of things that I think we can bid
farewell to in 11. Note that many of these are for ISA devices.
asr(4): This is a driver for a set of older Adaptec PCI RAID adapters. This
driver is _really_ crufty and is the only thing I didn't convert to
callout(9) because it has no notion of software state for a given
request. It is also 32-bit only since it stuff kernel pointers into
32 bit fields in hardware-defined structures.
mcd(4): This is a driver for a pre-ATAPI ISA CD-ROM adapter. As noted in
the manpage, this driver is only useful as a backend to cdcontrol to
play audio CDs since it doesn't use DMA, so its data performance is
"abysmal" (and that was true in the mid 90's).
scd(4): Similar to mcd(4), this is a pre-ATAPI ISA CD-ROM adapter. (Note
that the more-popular matcd(4) driver that was used for the CD-ROM
controller on certain SoundBlaster cards was removed in 2002.)
si(4): This is a driver for an older ISA/EISA/PCI multiport serial card.
It doesn't use bus_space. It was hacked up to use new tty, but
still uses Giant. I have a partial set of outstanding patches to
this to fix it to use bus_space, but when I sent them out for
testing on current and stable, no one replied.
wds(4): This is an ISA SCSI HBA that does not use DMA (only PIO). I
actually had one of these a long time ago to use with a SCSI
ZIP drive. Even if I still have it in a box somewhere, I'm not
digging it out.
wl(4): This is a driver for an ancient pre-802.11 wireless adapter. It
also includes wlconfig(8). Warner promises he won't test any
patches for this. It's older and slower than wi(4) and that driver
hasn't really worked in years. (One could make the case for axing
an(4) and wi(4) as well, but I'm just pushing for wl(4).)
spic(4): At one point the Sony VAIO was "the" cool laptop, and this driver
controlled the "jogdial" found on it and presented it as a mouse.
This is a tiny driver and is less invasive in terms of future
maintenance than others perhaps, but my recent calls for testing
on current@ and stable@ found no takers. It's a fairly obscure
device and not one that exists on any recently shipped hardware.
ie(4): Unfortunately, someone actually found one of these and tested it
several years ago when I added locking to it. It is the only ISA
NIC driver that doesn't have a pccard attachment (you can in theory
still use a pccard NIC in a cardbus slot (though not ExpressCard)).
This also only does 10Mb using PIO (no DMA). It doesn't use
bus_space.
--
John Baldwin
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