28 Jan
2008
28 Jan
'08
7:08 p.m.
On Mon, Jan 28, 2008 at 12:20:46PM -0800, Jon H wrote:
Hey all,
I've been having problems trying to find a realtime kernel that has
decent wireless support. I tried JAD 1.0, which performed quite
nicely, but did not have adequate wireless support or even madwifi
"out of the box", which I apparently need. I'm running a D-Link
DA-2320 PCI card which uses the Atheros chipset (madwifi?) and when I
inquired about it on their forums it didn't seem to take much
priority. I think 64Studio also struggled with this card but it's
about the only chipset locally available that has any track record at
all with linux. This card IS quite nicely supported under Ubuntu and
family "out of the box" but the kernel supplied with UbuntuStudio,
while it handles my wireless nicely, is more sluggish, in regards to
latency, than the vanilla Ubuntu kernel.
I'm not afraid to try building a kernel for myself, just wondering why
so many realtime kernels seem to lack the proper wifi support that IS
available to linux in general? I also seem to remember reading
somewhere some problem with certain wifi drivers co-existing with a
stack or something needed for realtime?
My guess would be either licensing, or the legwork required to dig around for the drivers,
or dealing with reliability (or lack thereof).
The drivers for my rtl-based wifi USB cards are very flaky and just barely usable, and
available either from the manufacturer or from random project websites (not built in to
the mainstream kernel). Also, there is a confusing mish-mash of competing, duplicated
drivers and forks. It's a mess. If I were distributing a kernel there is no way
I'd include them.
The good news is, I was able to build and test nearly all of the drivers for my USB wifi
cards without having to recompile the kernel at all! The source packages build them as .ko
modules outside of the kernel source tree. One of them even came with a nice hacky
shell-script to copy the drivers over to /lib/modules/`uname -r`/kernel/drivers for me.
-ken