|| ||Francesco Gringoli <francesco.gringoli-i2lwkhdiEHM3ahhDiVHSzw-AT-public.gmane.org>|
|| ||opensource firmware|
|| ||Fri, 9 Jan 2009 09:21:52 +0100|
|| ||Article, Thread
we have been involved in the past few months in testing modifications
to the standard 802.11 MAC for research purposes. During this time we
did some tests with Broadcom 802.11b/g boards and we wrote down a
simple 802.11 compliant firmware that we used as a starting point for
the modified MAC algorithms.
Although the base firmware is not fully 802.11 compliant, e.g., it
does not support RTS/CTS procedure or QoS, we believe that someone
could be interested in testing it. The firmware does not require the
kernel to be modified and it uses the same shared memory layout and
global registers usage of the original stuff from broadcom to ease
loading by the b43 driver (and ease our writing...). We wrote it to
make the b43 driver recognize it as Broadcom version 5 firmware: it
still uses the original initval files of that version of the
Broadcom's firmware, we do not include them as usual users have to
extract these files following the b43 installation instructions.
Lorenzo and I tested this firmware only on 4306 and 4318 hardware (pci
and minipci, pc-card based architectures seem to have problems), and
we did simple tests on the integrated board of a Linksys WRT54GL, so
we are quite sure it runs on 4306, 4318 and 4320 cards. We did all the
works on kernel 2.6.27-rc5-wl.
The firmware along with the instructions to build it from the assembly
code using the tools developed by the b43 community can be found here
In the firmware website you can find more information about the fw
algorithm, its interaction with Broadcom hardware and other
information that we discovered as we were writing it.
We would like to underline that this work would have not been possible
without the instruments already developed by the b43 community
(assembler/disassembler), hardware specifications (sipsolution's
website), the opensource test firmware written by Michael Buesch and
useful talks with those guys (b43 developers), which we deeply
acknowledge. As we used several definition files written by Michael
for its firmware and we have prepared a source tar file that includes
them, we kindly ask Michael if this could be a problem.
Finally we stress that this is a TEST firmware and some stuff needs to
be fixed (e.g. RTS/CTS and QoS), we have been using it as a starting
point to implement other MAC algorithms for research purposes: if
someone is interested in this kind of work and would like to share
ideas also on research topics, please let us know.
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