100% open (or almost open) platform for hobby OS development

[MasterM]

Hello. Sorry if this kind of question has been asked before. I used search but could not find anything.

Small, affordable embedded boards like Rspberry Pi or Beagle Board are becoming more and more popular these days. Most of them however use proprietary hardware (like custom Broadcom chips). Is there any such platform that is built (almost) entirely of open components? By "open" I mean that official documentation detailed enough to write a fully functional driver, without reverse-engineering anything, is freely available for that particular piece of hardware.

Thank you for all your suggestions.

[AJ]

Hi,

Does Arduino meet your requirements? Not sure what sort of processing power and peripherals you want available. If you want something completely open and an AVR is powerful enough, it wouldn't be too difficult to design your own board. Of course, once the controller / processor becomes more complex, this would be more problematic.

Your question title does say "or almost open". Is Raspberry Pi not open enough for you? There is a binary blob which acts as a bootstrap and allows you to interface with the GPU but other than that, it seems fairly open to me.

Is your concern about the openness of the platform for technical or licensing reasons?

Cheers,
Adam

[MasterM]

Does Arduino meet your requirements?

No. I want a general-purpose computer and I'm more interested in software development than designing my own hardware.

Is Raspberry Pi not open enough for you? There is a binary blob which acts as a bootstrap and allows you to interface with the GPU but other than that, it seems fairly open to me.

Will I be able to use the GPU fully - as in hardware acceleration and OpenGL-like thing on my OS?*. Is there specification available for the on-board Ethernet controller in Model B that would allow me to write a fully functional network driver?

Is your concern about the openness of the platform for technical or licensing reasons?

Technical reasons.

* I know it's a looong way to even think of stuff like OpenGL or any form of graphics and I will probabbly never reach that point, nevertheless I feel that this question is still valid to ask.

[AJ]

Hi,

Will I be able to use the GPU fully - as in hardware acceleration and OpenGL-like thing on my OS?

While I am not an authority on RPi, I am 99% sure that the answer is yes. There were initially a lot of disgruntled people on the forums due to the requirement of a proprietary binary blob. The official answer was that the internals of the GPU were counter intuitive anyway and that the binary blob gave access to all GPU functions.

Linux distro's are being ported with no additional information from Broadcom and they are now starting to make full use of the graphics acceleration.

Is there specification available for the on-board Ethernet controller in Model B that would allow me to write a fully functional network driver?

Yes. At http://elinux.org/RPi_Documentation there is a link to the full LAN datasheet, CPU/Peripheral datasheets, schematics and more.

Cheers,
Adam

[Owen]

Hi,

Will I be able to use the GPU fully - as in hardware acceleration and OpenGL-like thing on my OS?

While I am not an authority on RPi, I am 99% sure that the answer is yes. There were initially a lot of disgruntled people on the forums due to the requirement of a proprietary binary blob. The official answer was that the internals of the GPU were counter intuitive anyway and that the binary blob gave access to all GPU functions.

They use Broadcom's binary blob libGL & kernel module, which are intimately tied to Linux. Also, the documentation of some other areas of the hardware is rather lacking.

The BeagleBoard/Bone, PandaBoard and HawkBoard are the closest you're going to get. OK, on all of them you don't get information for the GPU, but all the other hardware is documented (including the framebuffer) - and nobody documents their GPU. If you want a fully documented SoC, you'll have to get one without a GPU... and nobody makes a board with said SoC as the ones with a GPU only cost 50c more.

The BeagleBone is my primary ARM target platform; at $99 you can't beat it for documentation & cost.

[AJ]

Hi,

They use Broadcom's binary blob libGL & kernel module, which are intimately tied to Linux. Also, the documentation of some other areas of the hardware is rather lacking.

I'm not denying that they are tied to Linux (after all - I'm an interested observer rather than being involved in any way), but there are RiscOS and Android ports for Raspberry Pi. Perhaps these just ignore hardware accelerated graphics? (I've just read this back and realise it may sound sarcastic - no sarcasm intended!)

Cheers,
Adam

[Owen]

Hi,

They use Broadcom's binary blob libGL & kernel module, which are intimately tied to Linux. Also, the documentation of some other areas of the hardware is rather lacking.

I'm not denying that they are tied to Linux (after all - I'm an interested observer rather than being involved in any way), but there are RiscOS and Android ports for Raspberry Pi. Perhaps these just ignore hardware accelerated graphics? (I've just read this back and realise it may sound sarcastic - no sarcasm intended!)

Cheers,
Adam

Android can probably use the same binary blob (or an equal android binary blob). RiscOS has never had hardware accelerated graphics (To think: Antialiased fonts. In 1990. On an ARM2)

[AJ]

To think: Antialiased fonts. In 1990. On an ARM2

[vialator]

There is openrisc: http://en.wikipedia.org/wiki/OpenRISC_1200

Its completely open RTL and a pretty easy to learn risc architecture that has an MMU and some other cool features like shadow registers for quick context swaps. You can get some cheapish (under 300) fpga development boards that can run the processor and develop for it. Linux and gcc are already ported.

If you're looking for a completely free stack from hardware to software, Openrisc is the way to go, but there are some other free/libre softcores such as leon (sparc32 architecture) and S1 (sparc64), but openrisc has the biggest open community and most support for modern fpga development boards.

[babylon2233]

This + openRISC might be the perfect combination you're looking for.

[lpcstr]

What we need is massively parallel CPUs. Something with like 32 or 64+ RISC cores on a single chip. Then you could just stick to doing graphics related stuff with software and forgo all the FPGA or proprietary driver garbage.

[Combuster]

Already done

[lpcstr]

Already done

Tilera is nice and all, but its lack of FPUs makes it a poor choice for GPU replacement.

Intel's teraflops research chip was about the closest thing I've seen.

[AJ]

Slight thread necro here I thought of this post again when I just read this from the Raspberry Pi Foundation http://www.raspberrypi.org/archives/2221.

Cheers,
Adam

[cb88]

I'm supprised noone has mentioned parallela... its basically Arm Cortex-A9 + 16 paralell processors with FPU and a decent cache on each of them.

There is a kickstarter for them which just reached its goal... they are also talking about making a 64 core version presuming adequate funding.

http://www.kickstarter.com/projects/ada ... r-everyone

OT: Posting from Haiku! Built from git BTW its finnally working on my laptop again after about a year. They must have straightend out all the itterrupt handling stuff that got messed up witht he ACPI change.