Calling interested Glamo OpenGL developers (was: The forbidden topic: Glamo OpenGL)

Lally Singh lally.singh at
Fri Nov 21 07:17:38 CET 2008

Wolfgang, Raster:

On Thu, Nov 20, 2008 at 11:28 PM, The Rasterman Carsten Haitzler
<raster at> wrote:
>> >  The GTA02's been on the brink of obsolescence since the day it was
>> > introduced.
>> Don't agree with you. In the long run everything is obsolete.
> i think he is referring to using an "old soc", "old gfx chip" etc. something
> that has been out for many years - where the "competition" (not in open phones,
> but in phones in general) is busy building new devices on chips not yet in mass
> production as they follow the curve and by the time it is in production - their
> device is ready. it's perfectly understandable why openmoko is building on an
> old platform - but it still makes the hardware very much "behind the curve" :)

I suspect the Glamo was designed for a much less sophisticated setup,
with a lower-res screen and probably a slower CPU.  Hence the texture
sizes and I/O speed limitations -- choices made for cost & power.

> <snip>
>> > If the Glamo (or something compatible) is going to be around for a
>> > while, either in
>> > a long production life of the GTA02, or in newer phones,
>> Long production life of GTA02.

I'm all for longer production lives.  But, IMHO in the next
incarnation, some more thought to a longer useful life  should be
given.  Specifically, a few more ports on the device are necessary to
keep its useful life long.  LInuxer's will add drivers for new devices
as they come, extending the life of the device, but we need I/O.

Additionally, the components chosen shouldn't be as overtaxed from the
beginning as the glamo.  Only after the driving software has been
written does a team find out the real limitations of the device.
Started from a burdened position usually only leads downward after
trying to get aggressive on the software side.  IMHO 3D was/is a great
idea, so I can't blame OM for trying with the glamo.  But there are
alwasy some lessons to come out any development effort.

Finally, the next device should have stable support for basic phone
operation when it's released: suspend, resume, calling, and
answer-while-suspended.  Without that, it's hard to get the
imagination going for what else to do with the phone.  The GTA02's
release should have been in two phases for hackers and users.  The
former as it was, the latter after those functions were stable.  If
that's not possible for the GTA03, then a two-phase release is
appropriate for it, too.  The nice consequence of it is that it brings
in larger community participation of the device's commercial
lifecycle, which will lead to a better feeling of community ownership
over it.

I admit I was quite embarrassed to show the device off upon reception,
considering how really raw it was.  I'm happy with the results of the
optimization team, and it looks like OM's going the right way now.
But it was quite painful for too long, and shouldn't be repeated.

>> >  Hence, my earlier suggestion on just using the acceleration for some
>> > Gtk operations.  Small, effective changes.  Get that done to make the
>> > device feel responsive.  If someone wants to do the big OpenGL
>> > implementation later, fine, use this Gtk work as a sandbox for getting
>> > a feel for the device.
>> Very good idea. I always prefer breaking a large idea into smaller
>> pieces.
> one thing everyone seems to think that is wrong. this "gtk acceleration" is
> already done. blits, fills. xvideo too. :) <snip>
> so right now other than bugs and trying to minimise cpu overhead on handling
> the commandqueue 2d is done - it's not getting "faster". only thing left is 3d.
> and that comes with a long list of gotchas. this is the bit where someone needs
> to make a call on "what is the effort needed, and the result". this is up to
> openmoko to decide what to do as the docs are in their hands. 2d is pretty much
> done. :)

As Raster's already pushed hard on Glamo acceleration, and I know he's
quite capable (I was an old enlightenment WM user back in the day), I
consider the glamo issue closed.  We're stuck with what we have, and
simply have to find ways to be efficient with what what's already

>> 1. We currently are disappointed about s-media. To be fair to them I
>> do not want to quote from contracts we have with them, but let me tell
>> you at the bottom line we feel there have been some broken promises
>> with regards to opening documentation.
>> 2. Because of this situation, we decided to not use s-media chips in
>> future Openmoko products.
>> 3. At the same time, we decided to not come out with GTA02 versions
>> that had the glamo removed, because that would have been hard to do
>> technically, and it would have created too much technical fragmentation.
>> 4. Even with raster's bashing, the glamo chip is a really nice mobile

That isn't stuff you could've known before committing this far.  I'm
sorry it happened to a platform I like so much.  I support your
decision of keeping it in, otherwise you'd lose a lot of your
community.  Nobody likes buying an iPod the day before the new ones
come out.

3D was the right way to go, and I support it as a long-term objective.
 Whether this means choosing a GTA03 platform with really good Mesa
speed, or another accelerator (preferably with both a vendor-supplied
GLX driver and source documentation), it should be part of OM going

> it's a professional opinion based on what i have seen in my years of doing
> graphics. i think it's a very very weak graphics chip with lots of missing
> holes in its featureset - given the kind of screen attached to it and the OS
> and windowing system as well as the goals and desires of users. if you take the
> OS and windowing system and goals as a given, the weak point is the glamo. a
> spade is a spade. :) you can cover it with topping all you like. :)

I'm taking a protective role for the community in all this.  IMHO the
community's what makes the OM phone interesting.  I'd rather not see
well-intentioned hackers spend long months on a venture with little
likely return.

> <snip>
>> Openmoko's speed of progress still does not match industry speed.
>> While the other (closed) chip vendors are already 2 generations ahead,
>> we (Openmoko and the Free Software community) are still writing
>> drivers for older chips. But we shouldn't let others distract us. Our
>> software is 100% Free Software. We want to be able to install mainline
>> kernels one day. We want to be able to run many Linux
>> distributions on the phone one day. We are coming from behind, but I'm
>> sure with the help of the community we can even drag something like
>> the glamo out into the open.
>> 5. We will have the same problem with open 2D/3D acceleration again in
>> the future, so breaking the glamo free could be considered a good
>> 'exercise'. No matter whether you look at future Samsung, TI, Marvell
>> chips. The 3D acceleration part is always closed. In other words needs
>> to be opened by us. We might as well start with the glamo now, better
>> than waiting for the 'perfect moment' which will never come...
> yeah. the future and "3d accel" is a minefield. no one wants to be open about
> it. there are definitely viable solutions to this. hardware-wise. and they
> involve saying "screw it" to the 3d cores on soc's. you can get multi-core high
> speed co-processors that could be programmed to do 3d - or 2d, or media
> decoding.. or anything. and they are cheap and very low power... but... not
> easily available in silicon (yet).

By the time the GTA03's entering its lifetime, hopefully there should
be some good options available.  I like the idea of one or more vector

Of course, we could just look for an embedded Sony Cell :-P

H. Lally Singh
Ph.D. Candidate, Computer Science
Virginia Tech

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