u-boot + Linux kernel port to Mediatek MT6235 baseband processor under way
I am really excited about some recent work by Marcin on starting a u-boot and Linux kernel port to the
Mediatek MT6235 baseband processor.
Among GSM baseband processors, the MT6235 is a very unusual device. Unlike
classic GSM baseband chips, it is not based on an MMU-less ARM7TDMI/ARM7EJS but
on an ARM926EJS core. This is a full-blown ARMv5 core on which a standard Linux
kernel could run.
The reason for the MT6235 to contain such an 'advanced' ARM core is simple: Mediatek
is producing chipsets and reference designs for very inexpensive but feature-rich
phones. Instead of going to a full-blown (and expensive) smart-phone design
with separate ARM cores for the baseband and application processor, they simply make
the base-band processor a bit stronger than needed for the GSM stack, and run the entire
rich UI on the same cpu, including TCP/IP stack, touch-screen, web browser,
e-mail client, H.264 playback / camera recording, etc.
The original firmware on the Mediatek chipsets is a Nucleus-kernel based software stack
which is completely proprietary.
Now the mid-term vision for us is to have a Linux port to the MT6235, and run the OsmocomBB
Layer1 (and possibly Layer2) code inside the kernel, while the Layer3 and a user interface
program is running as application programs in userspace.
This would allow us to do a very rich user interface (imagine network
monitoring modes, protocol tracing, manual cell selection, etc.) while still
having to care only about one processor in the system. Furthermore, there are millions of
MT6235 based devices, so there will be no shortage of inexpensive hardware to
run this code on.
The MT6235 also has a built-in SD/MMC controller (for storing e.g. protocol traces that you
take from the GSM network) and it has a fast, dual-mode USB2 high-speed USB controller
for connecting it with a PC
Sure, porting our Layer1 to a completely different baseband chipset will be a lot of work,
and I don't really have any idea how long it will take us. But I think the vision of
such a powerful device (and finally bringing OsmocomBB and the Linux kernel together)
should prove a very attractive motivational factor.
This also means: Even if you have no clue about the GSM protocols, you can now start to
contribute to OsmocomBB: A lot of Linux kernel drivers for e.g. SD/MMC, USB, frame-buffer,
SPI, I2C, PWM and other integrated controllers of the MT6235 need to be written.
Like all Mediatek data sheets, the MT6235 data sheet describing all those peripherals can
be found on various places on the Web, including (but not limited to) Chinese
developer forums.
It also seems there is at least one MT6235 based phone where JTAG and serial
console have been identified (Sciphone Dream G2), which should make debugging
and bootstrapping convenient.
[ /gsm/osmocom-bb |
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The ELCE 2010 keynote by Ari Rauch (Texas Instruments / OMAP)
I've just attended the ELCE
2010 keynote by Ari Rauch, where he was talking about how much TI OMAP is
committed to Linux. This doesn't really come as a big surprise to me. The
OMAP SoCs are used mostly as Application Processors for smart phones. As TI
is not a supplier of APs for Apple, Symbian and Windows Mobile are dead, this
really only leaves Linux-based operating systems like Android, Meego, LiMo &
co.
One of his main points was we have to be pragmatic, i.e. the customer
requirements for performance etc. are key. If there is an open way to fulfill
them: fine. If not: fine, too.
The only real question that was asked after the keynote was the usual question
of whether there will be any Free/Open graphics drivers for the Imagination GPU
thats inside their OMAP3/OMAP4 SoCs. I already predicted the response: We have
to be pragmatic about it. TI is trying to convince Imagination to open up,
but they are afraid of doing so and don't see what this would gain them.
He further added the statement if there is a competitive more open GPU, they
will look into using it.
The other bad taste I got from this keynote is the frequent mention of the
industry embracing innovation provided by the FOSS community.
Embracing was the very term that Microsoft always used when they started to
create their custom versions/dialects of HTML, Kerberos and other standards.
The think that seemed to be missing is any awareness for the sharing
attitude: I.e. the industry using the innovations that the community creates,
but giving back an equal amount, or at least opening up in response. This
cannot be a one-way road where the industry simply taps into the creative
potential of the community, to create closed products and profit from stuff
they have simply scraped off the community backyard.
[ /linux/conferences |
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ST-Ericsson glues gstreamer into Android - and makes it proprietary
It is always surprising what kind of things the industry is coming up with ;)
Here at ELCE, ST-Ericsson has just presented how they replaced OpenCore
with gstreamer as the supplier/provider of multimedia encoding/decoding
to the Android software stack.
This is definitely an interesting technical solution - probably one that makes
sense if you have existing gstreamer modules/drivers.
What really makes me wonder though, is their licensing. To make sure only
ST-Ericsson customers can use it, they have implemented a glue layer library
that ties into android, and this library is binary-only licensed and
distributed under terms that permit to use it together with their hardware.
Isn't it strange? Now the Android software stack is Free Software, and
gstreamer is Free Software. But ST-Ericsson needs to put some proprietary blob
in the middle. Of course, legally they are allowed to do it: Android is
Apache-style licensed and gstreamer is LGPL. But from a
moral/ethical/technical point of view, it still is blasphemy to me.
UPDATE: The license is actually a 'standard' proprietary license.
There seem to be technical reasons that tie this code to the specific SoC of
ST-Ericsson. Nonetheless, I keep my original criticism: It has a bad
aftertaste if you combine two FOSS programs by a proprietary layer in
between
[ /linux/conferences |
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GPL compliance workshop on December 2nd in Taipei, Taiwan
The OSSF at Academia Sinica in Taiwan has kindly organized a full-day GPL compliance
workshop on December 2nd in Taipei, Taiwan.
Armijn Hemel and myself will be presenting on a variety of topics regarding
GPL compliance, both from an administrative/organizational as well as a
technical compliance engineering point of view.
I think this is an excellent opportunity to get in touch with product managers
and engineers in Taiwan's computing and particularly embedded industry. We
definitely still need more awareness in that industry, as the majority of the
products in a variety of IT markets are predominantly designed in Taiwan.
So the better the know-how is there, the less GPL violations we will find
further down the supply chain and finally in the retail-stores around the
world.
Many thanks to the OSSF at Academia Sinica, and specifically Florence Ko and
Lucien Lin for making this workshop possible [and giving me a reason to come to Taipei again ;) ]
[ /linux/gpl-violations |
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The 7th netfilter workshop is coming up
The 7th Netfilter Workshop is
just coming up next week in Seville, Spain. Once again it will be hosted at
the ETS Ingeneria Informatica of
the University of Seville.
I'd like to personally thank Pablo Neira for organizing and hosting the event
again in Seville.
As most readers of this blog will know, my current relationship to
netfilter/iptables is somewhat dormant. I haven't been writing any code for
probably something like five years ago, when I was seriously distracted with
stuff like OpenPCD, OpenPICC, OpenBeacon and later the Openmoko project.
Nonetheless, it is always great to learn what Patrick, Pablo, Martin, Jozsef,
Yasuyuki and the others have been up to. With a slight chance I may actually
still have some advice/ideas or other input I can contribute.
[ /linux/netfilter |
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GPL violation reports in HTC G2 Android phone
There have been various reports and
blog posts about HTC again committing copyright infringement by not fulfilling the GPLv2 license conditions in their latest Android phone, the G2.
While at this point I haven't studied the situation enough in order to confirm or
deny any actual violations, let me state this: The number of GPL Violation
reports/allegations that we receive at gpl-violations.org on HTC by far
outnumber the reports that we have ever received about any other case or
company.
In addition, HTC seems to have had a long trail of problems with GPL compliance
in their devices. Ever since they have started to ship Android devices containing the Linux kernel, licensed under GPLv2+, we have received those reports.
The reason I have never taken any legal action is merely a result of the fact
that HTC seems to first introduce their new devices in the US, then at some
point release the corresponding source code before shipping those devices into
Europe and Germany. So by the time the devices are sold over here, the legal
issues appear to have been resolved before.
Nonetheless, I think it is outrageous for a company of this size and
significance in the market to consistently commit copyright violation (or at
least walk borderline with it) and thus mistreat the very copyright holders
that have created the operating system kernel they use in their devices. The
linux kernel developers and the Free Software community as a whole deserve fair
treatment.
Also, the competitors of HTC deserve fair treatment: Samsung, e.g.
is very forthcoming with their Android phone source code releases. If I was
them and would see HTC to fail to comply with the GPL, I would consider filing
a unfair competition lawsuit...
[ /linux/gpl-violations |
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FOSS.in/2010 CfP is closing
I just want to point out: If you haven't yet submitted a proposal for FOSS.in/2010,
the FOSS.in/2010 Call for Participation is closing in less than 48 hours!
This means you still have a chance to submit a talk, workout or BoF on your
personal FOSS, hacking or otherwise technology related work and actively
participate in the event.
FOSS.in is an excellent chance to spread the word about what technical work you
have been doing, and to motivate others to participate and join your projects.
It's a great opportunity to reach out to the Indian FOSS community, meet old
friends and make new ones. Don't miss it :)
[ /linux/conferences |
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