Toward An FSF-Endorsable Embedded Processor 258
lkcl writes about his effort to go further than others have, and actually have a processor designed for Free Software manufactured: "A new
processor is being put together — one that is
FSF Endorseable,
contains no proprietary hardware engines, yet an 800MHz 8-core version would,
at 38 GFLOPS, be powerful enough on raw
GFLOPS
performance figures to take on the 3ghz AMD Phenom II x4 940, the
3GHz Intel i7
920 and other respectable mid-range 100 Watt CPUs. The difference is: power
consumption in 40nm for an 8-core version would be under 3 watts. The core
design has been proven in 65nm, and is based on a hybrid approach, with its
general-purpose instruction set being designed from the ground up to help
accelerate 3D Graphics and Video Encode and Decode, an 8-core 800mhz
version would be capable of 1080p30 H.264 decode, and have peak 3D rates
of 320 million triangles/sec and a peak fill rate of 1600 million pixels/sec.
The unusual step in the processor world is being taken to solicit input
from the Free Software Community at large before going ahead with putting
the chip together. So have at it: if given carte blanche, what
interfaces and what
features would you like an FSF-Endorseable mass-volume processor to have?
(Please don't say 'DRM' or 'built-in spyware')."
There's some discussion on arm-netbook. This is the guy behind the first EOMA-68 card (currently nearing production). As a heads ups, we'll be interviewing him in a live style similarly to Woz (although intentionally this time) next Tuesday.
Those performance numbers are BS (Score:5, Informative)
Those performance numbers are pure fantasy. First off, the 38 GFlops is undoubtedly referring to single precision operations while the x86 processors mentioned in TFS are doing that much in *double* precision mode. Second off, the 38 GFlop number is a simple arithmetic estimate of what the magic chip could do IFF every functional unit on the chip operated at 100% perfect efficiency. Guess what: a real memory controller that could keep the chip fed with data at that rate will use > 3 watts all by itself. This chip won't have a real memory controller though, so you can bet the 38 GFlop performance will remain a nice fairytale instead of a real product.
Re:And no proprietary software either (Score:5, Informative)
If this processor is going to be designed and licensed under GPLv3 - I guess one won't be able to build any license-compatible proprietary software for it either. Curious - but count me out :)
ah interesting. no, it wouldn't be. i believe there are two separate misunderstandings here.
first: i did actually look some time ago at LEONv..... v2 i think it is, which is LGPL licensed i think by Gaisler Research but the amount of work needed to turn it into a modern GPU/VPU-competitive processor would be too costly. then there is the stuff on http://opencores.org/ [opencores.org] but it's not really ready for prime-time - i've been keeping an eye on the projects there for quite some time [none of them are SMP capable for example]
instead, i kept hunting, spoke to tensilica about their core (which is superb btw!), talked to synopsis about their core (ARC), and even came up with a way to do software-interrupt-driven SMP (yes i ran it by alan cox on LKML!). when this current design popped up, and i saw both its capabilities and that they are willing to respect the GPL regarding the toolchain, i jumped at the chance.
second misunderstanding is over design of *hardware* impacting what *software* it can run. it would be necessary to have a modified version of the GPL, stating "all and any software programs running on this hardware *must* be GPL licensed". the impact that this would have would be extremely problematic, as well as being rather fascist and not in the spirit of free software at all.... and, also, as it would be a modified version of the GPL, it wouldn't *be* the GPL, so could not be FSF-Endorsed.
with that as background, to answer the question directly: this is a proprietary design just like all other proprietary designs, using off-the-shelf completed and *tested* hard macros (including the core processor itself albeit only under the MVP Programme), where there is no restriction of any kind on the software that can be run on that processor, be it free software or proprietary software.
anyone can play, in other words.
Re:Vaporware? (Score:4, Informative)
From TFA:
>The deadline:
> July 2013 for first mass-produced silicon
>
>The cost:
> $USD 10 million
This poster has either no idea or is dreaming.
both. i have no clue - that's why i posted this article online, as a way to solicit input and to double-check things - and i'm dreaming of success.
In 6 months he will not have an SoC through potentially several tape-outs, having first done System Engineering, Design, Synthesis, Layout, Verification, Validation,
what i haven't mentioned is that one of my associates (my mentor) used to work for LSI Logic, and he later went on to be Samsung's global head of R&D. he knows the ropes - i don't. we've been in constant communication, and also in touch with some people that he knows - long story but we have access to some of the best people who *have* done this sort of thing.
Documentation,
ahh, my old enemy: Documentation. [kung fu panda quote. sorry...] - yes, this is probably going to lag. at least there will be source code which we know already works. not having complete documentation has worked out quite well for the Allwinner A10 SoC, wouldn't you agree?
also, because this is going to be a Rhombus Tech Project, the CPU will *not* be available for sale separately. it will *ONLY* be available as an EOMA-68 module. no arguments over the hardware design. no *need* to do complex hardware designs. the EVB Board will *be* the "Production Unit" - just in a case, instead.
so by deploying that strategy, Documentation is minimised. heck, most factories in China have absolutely no clue what they're making. it might as well be shoes or handbags, for all they know. heck, many of the factories we've seen actually *make* shoes and handbags, and their owners have gone "i know, let's diversify, let's make tablets". you think they care about Documentation? :) ... ok, i know what you mean.
yeah. it's amazing what you can do if you're prepared to say "i don't know what i'm doing" and ask other people for help rather than try to keep everything secret, controlled and "in-house". my associates are tearing their hair out, i can tell you :)
Or are SoC manufacturers lately doing short-term build-to-order processors. And the 10 million are not going to cover the necessary cost for all of the above. The masks alone might be that expensive depending on the number of tape-outs necessary (which - without an existing organization and working design flow - will be a lot).
well, because i know nothing, i've asked people who do know and have a lot of experience. the procedure we'll be following is to get an independent 3rd party - one that partners with the foundry - and get them to do the verification, even if the designers themselves have run the exact same tools. if it then goes wrong, we can tell them to fix it... *without* the extra cost of another set of masks. a kind of insurance, if you will.
but the other thing we are doing is: there will be *no* additional "design". it's a building-block exercise. the existing design is already proven in 65nm under the MVP Programme: USB-OTG works, DDR3/1333mhz works, RGB/TTL works, the core works, PWM works, I2S works, SD/MMC works and so on. all we're doing is asking them to dial up the macros to put down a few more cores, and surround it with additional well-proven hard macros (HDMI, USB3, SATA-II).
does that sound like a strategy which would, in your opinion, minimise the costs and increase the chances of first time success?
Re:Feature Requests, Now that you asked (Score:5, Informative)
"So have at it: if given carte blanche, what interfaces and what features would you like an FSF-Endorseable mass-volume processor to have?"
thank you for taking me literally! really appreciated!
Standard size chip socket, with adapter springs and guides for using off the shelf cooling implements (like zalman fans, and watercooling), for other CPUs.
ah. this is going to be a 15mm x 15mm BGA with only around 320 pins. it's tiny. ok, that might have to be revisited now that i thought about doing an 8-core monster - 3 watts in a 15 x 15mm package is hellishly hot.
i'm still debating whether it should have dual 32-bit DDR3 lanes. even so, that only adds an extra... 75 or so pins, bringing it up maybe to 19 x 19 mm.
need PCI and PCI express, prefrably at least 24 lanes, hopefully as many as 48 lanes.
ahhh... PCI express is a bug-bear. that many lanes would, on their own, turn this into a 12 to 30 watt part: right now we're aiming for a different market. i'm happy to be steered in a different direction if it can be shown that it's a genuinely good idea, with a high chance of return on investment.
Behind this, fast northside/southside busses to keepup with the following, I think AMD open sourced hypertransport, so front side bussing should not be an issue.
ah this is an embedded processor: they don't have northbridge/southbridge buses [at all]. those are reserved for CPUs at the 10+ watt market.
If your still mulling over instruction set, a built in crypto proccessing chip would ROCK. implement intels AES-NI or something similar, plus more for twofish, serpent, and other fairly mainstream modern, unbroken Free/Open encryption algorythms. Then add hash instructions for the entire SHA family of hashes, MD6, whirlpool, tiger, RIPMED, and GOST
ok - this is a general-purpose processor that *happens* to have been designed to be capable of doing a GPU and a VPU's job. hmmm... i wonder whether their instruction set can do crypto primitives.. hmmm.... yeah, that's a great question to ask. i'll get back to you on that.
GOOD USB 3 support, with legacy suppoequivsrt for 1 and 2. Not only do I want some ports on the back, I want at least 3-4 banks of header pins on a theorhetical motherboard for front panel devices and ports. They shtheorheticalould be USB 1,2,3. Solid high speed memory controller at a preimium.
definitely going to have 1x USB-OTG, probably 2x USB2-HOST, and at least one USB-3.
Universial SATA support for revisions 1,2 and 3 (1.5GB/s 3.0 GB/s and 6.0 GBs respectively), built in RAID controller. eSATA would help too.
i'm reluctant to push this IC towards 6gb/sec - it'd be by far and above the fastest bit of I/O on the chip. RAID i'd be concerned about pushing up the cost for the mass-volume uses [which wouldn't use it]. eSATA is _great_. i'd forgotten about that.
scalable audio chipset capable of up to 8.1 surround, Stereo input, SPID/F and all the other great audio features.
SPDIF - i'd not *entirely* forgotten about that - will remember to make a mental note. audio i would like to rely on the processor itself for that sort of thing (for basic audio - headphones and the like), otherwise handing off to a standard I2S/AC97 audio IC for cases where people really want more complex audio. there are 3 I2S interfaces i think.
so, yeah - i want audio to be done more like the TI McBSP. DMA-driven, but use the main processor for audio handling. keep it simple.
DDR3 RAM, or something comparable.
already done. 1333mhz. bit concerned personally about the power consumption of 1333mhz, i know that 800mhz is about 0.3 watts for example: 1333mhz is starting to get to 1 maybe 1.5 watts all on its own!
Unlocked bootloader with firmware m
Re:x86 - NOT!!!!! (Score:3, Informative)
So you're volunteering to write the compiler, right?
the team's done it already.
And porting Linux to a completely new architecture?
and that, too. and android on top of that.
relax - it's been taken care of. come on - think, 007. would i *really* have put this up as a proposal if the compiler and the linux port hadn't already been done? doh! :)
Re:DRM (Score:3, Informative)
For example the original xbox could be convinced to run unsigned code through exploited game saves and then system files(fonts/audio db) could be replaced with corrupted versions meant to trigger an exploit on bootup. This is how soft modding was performed for the xbox.
Re:And no proprietary software either (Score:4, Informative)
Hmm, one problem I have with the full GPL is that it *is* by design rather intent on spreading itself virally and to the exclusion of other legitimate models, and thus a restriction on what software the hardware would be allowed to run would be unfortunately in keeping with the GPL.
you are absolutely, absolutely dead wrong. waaayyyy off base.
I agree that that would be excessive, but then I think that the full GPL is generally excessive.
You may guess that I prefer to license my stuff under BSD licences to allow fully commercial uses. B^>
Rgds
Damon
and how's that working out in the android community? you've seen the list of GPL violations as people mistake "android equals linux", yeah? it's a serious problem, and it's why i started the whole rhombus-tech initiative: to get free software developers involved right from the beginning in the mass-volume industry, right the way through to sales in hypermarket retail stores. the "dream" if you will is for free software people to be able to walk into a supermarket and go go "fuckin'A! i helped write the software for that! you wanna buy one of these, grandma, i can replace the OS in no time, with something that i can manage remotely for you".
you have to remember that the BSD license was designed and written at a time when everyone trusted (because they knew them personally) everyone else in the industry. *everyone* shared source code. then fuckers like apple came along and went "thank you very much. BYE". at one point, microsoft's NT Team took the TCP/IP BSD-licensed stack, and put it directly into MSRPC (because winsock was so shit). it's almost 20 years later that Wine have finally reverse-engineered MSRPC. i really don't understand people who don't understand why the GPL is so necessary, i really don't.