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

Carsten Haitzler (The Rasterman) raster at rasterman.com
Fri Nov 21 05:28:42 CET 2008


On Fri, 21 Nov 2008 11:59:42 +0800 Wolfgang Spraul <wolfgang at openmoko.com>
babbled:

> Lally,
> 
> > how long is OM going to be using the Glamo?
> The glamo will be kept for the lifetime of gta02, i.e. every gta02  
> will have the glamo chip.
> For gta03, release date unknown, the decision is to not have a glamo,  
> we use the acceleration of the SoC.
> 
> >  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 In the long run everything is obsolete.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" :)

> GTA02 is a real pioneering device for Linux in mobile phones, and is  
> still advancing the state of Free Software in mobile phones in many  
> areas.
> We owe the community better hardware, and have made decisions  
> internally to only focus on hardware and lower-level software.
> But that will not remove the pioneering status of GTA02, not even when  
> GTA03 ships, again release date unknown at this point.
> 
> > It can't even take most modern (3G) SIMs.
> Thanks to great work from Dieter, Joerg and Werner, this bug (trac  
> #666) seems to be fixed now, GSM reflash utility and instructions are  
> available, etc.
> Next they target trac #1024 (network re-registration).
> 
> > 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.
> 
> >  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. :) aa text isn't possible as the glamo
doesn't meet xrender specs for doing aa text, so it's software or bust (unless
you upload ARGB glyphs and pre-colour them. the end result will be slower
rendering that current software - that's my bet). so you are about as good as
it gets - acceleration-wise for "gtk" (2d). only thing that could be done is
some basic xrender accel (composite ARGB32 src to rgb565 dest if src and dest <
640x640). and that also involves having to have uploaded the ARGB32 pixel
source first - which is double the bandwidth needs of 16bit... across the bus
to the glamo (thus why i originally was so focused on trying to squeeze more
out of that bus - that is a real killer).

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. :)

> >  $400 for a phone is a reasonable investment.  But months of work in
> > one's spare time is much bigger.  Before anyone commits to a
> > large-scale project, I think it's fair to ask OM what their plans are
> > with this chip.
> Absolutely. I have already answered many aspects in other mails, but  
> let me summarize again:
> 
> 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  

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. :)

> graphics chip. I say this also considering when it was released.  

indeed. when it was released it was good. but that was long ago. i agree here.
in the context of a product produced in min 2008... (see above... :)).

> 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  
> kernel.org 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).

> Best Regards,
> Wolfgang
> 
> On Nov 17, 2008, at 3:40 PM, Lally Singh wrote:
> 
> > Well then,
> >
> >  Therein lies the question, how long is OM going to be using the
> > Glamo?  There's apparently some real potential in the device, but
> > that's really measured as much by the chip's relevance as its
> > functionality.
> >
> >  The GTA02's been on the brink of obsolescence since the day it was
> > introduced.  It can't even take most modern (3G) SIMs.  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, then all this
> > makes sound engineering sense to work on.
> >
> >  Otherwise, I have real doubts about the longevity of a software
> > project aggressive enough to attempt major work (e.g. accellerated
> > OpenGL) on this chip.  Lots of open source projects start off with a
> > bang of enthusiasm, and die with a whimper.  If the chip's gone in a
> > few months, I don't think we'll see the project survive.
> >
> >  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.
> >
> >  $400 for a phone is a reasonable investment.  But months of work in
> > one's spare time is much bigger.  Before anyone commits to a
> > large-scale project, I think it's fair to ask OM what their plans are
> > with this chip.
> >
> > -ls
> >
> > On Sun, Nov 16, 2008 at 11:43 PM, Neng-Yu Tu (Tony Tu)
> > <tony at openmoko.com> wrote:
> >> -----BEGIN PGP SIGNED MESSAGE-----
> >> Hash: SHA1
> >>
> >>> Those are some good questions.  From what I understand the Glamo is
> >>> fixed-function and supports OpenGL ES 1.1.  As far as changing  
> >>> Xglamo to
> >>> be based on X over kdrive, I think to start, it would be best to  
> >>> leave
> >>> Xglamo the way it is and just add-in OpenGL ES support, but if there
> >>> were people dedicated to getting X support I would vote for it.
> >>>
> >>
> >> Glamo3363 support:
> >>
> >> * OpenGL ES 1.0
> >> * OpenGL ES 1.1
> >> * Mobile D3D
> >>
> >> 3D pipe line:
> >>
> >> * transform
> >> * cull
> >> * lighting
> >> * clipping
> >> * setup
> >> * rasterizer
> >>
> >> The glamo datasheet is full of register settings, as wolfgang said,  
> >> we
> >> hope could resolve this NDA issue in someway that could help people
> >> develop 3D development on FR.
> >>
> >> - --
> >> Neng-Yu Tu (Tony Tu)
> >> Openmoko, Inc.
> >> Support.
> >> -----BEGIN PGP SIGNATURE-----
> >> Version: GnuPG v1.4.9 (MingW32)
> >> Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org
> >>
> >> iEYEARECAAYFAkkg9oEACgkQmV6sZhhBn2+FKQCgq+A2HsKkNTlKHvZgi/zjlale
> >> qXsAn2gi5L3cc0/SKjYF54ve6KtzIABW
> >> =fJkN
> >> -----END PGP SIGNATURE-----
> >>
> >> _______________________________________________
> >> Openmoko community mailing list
> >> community at lists.openmoko.org
> >> http://lists.openmoko.org/mailman/listinfo/community
> >>
> >
> >
> >
> > -- 
> > H. Lally Singh
> > Ph.D. Candidate, Computer Science
> > Virginia Tech
> >
> > _______________________________________________
> > Openmoko community mailing list
> > community at lists.openmoko.org
> > http://lists.openmoko.org/mailman/listinfo/community
> 
> 
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> 


-- 
------------- Codito, ergo sum - "I code, therefore I am" --------------
The Rasterman (Carsten Haitzler)    raster at rasterman.com





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