3 ms·

I understand the notion here that opening up ThreadX will start to allow visibility into VideoCore, since ThreadX runs the thing. But an RTOS/scheduler is only

I understand the notion here that opening up ThreadX will start to allow visibility into VideoCore, since ThreadX runs the thing. But an RTOS/scheduler is only a miniscule part of a GPU and since Broadcom never opens up anything, I believe it's a false hope. Opening up any GPU code, from any maker, invites patent lawsuits from competitors. And then the injunctions start flying.

Zigurd 3y ago
Can confirm: same story for PowerVR. It's a double whammy: They want the driver licensing revenue and they are afraid of patent trouble.
- jauntywundrkind 3y ago
  I was going to point out that Linux 6.8 seems on target to be shipping pretty decent powervr drivers, but yeah, probably a huge massive chunk of the magic is in the firmware blob, which is closed as heck as usual for this industry. Both drivers & boob very recently dropped: https://www.phoronix.com/news/PowerVR-Firmware-Blob https://www.phoronix.com/news/PowerVR-Firmware-Blob I think though they're finally realized trying to charge people for drivers has made them a hated name & gotten them no where. GMA500 is a long awful wound on everyone & held Intel back from being much better at embedded than they could have been. Powervr has been one of those living embodiments of the phrase "expensive chips without good drivers are just expensive sand", or however it goes. So now this stuff hypothetically is going to start to be broadly usable (only on Linux underimited architrctures I guess? Since it's mostly binary blobs?).
MegaDeKay 3y ago
"Broadcom never opens up anything". True, but from a link in the related article from The Guardian [0] > Broadcom when they developed the original Videocore firmware bought a licence for ThreadX from the writer. AIUI, a lifetime licence, it never expires. No royalties or anything like that. Raspberry Pi have modified that firmware many many times over the last 10 years, but no royalties to pay. Many years later the writer of ThreadX sold the thing to Microsoft. So sounds like the RPi folks have a free hand over this firmware and they might be able to open it now? [0] https://forums.theregister.com/post/reply/4735439 https://forums.theregister.com/post/reply/4735439
- joezydeco 3y ago
  I believe it's wishful thinking. I wish all you RPi fans the best in your endeavor.
  - robertlagrant 3y ago
    > I believe it's wishful thinking. Why?
  - Andrex 3y ago
    Maybe a clean room recreation is possible? Or are those straws even further out of grasp...
    - bri3d 3y ago
      Sure, and it's been done: https://github.com/christinaa/rpi-open-firmware https://github.com/christinaa/rpi-open-firmware - but that doesn't involve ThreadX source, just some standard reverse engineering work. ThreadX is really the least interesting part of this whole operation in terms of the Raspberry Pi. It's very cool that ThreadX has been open sourced as it offers an additional battle tested and mature alternative to FreeRTOS for new projects. If they're able to get and maintain the various safety certifications for ThreadX under the Eclipse foundation, this could be game-changing in a very different space from the Pi. But in terms of reverse engineering or open sourcing the Raspberry Pi VideoCore blob, open source ThreadX is pretty much a non-event IMO.
- seba_dos1 3y ago
  FWIW, the firmware is how they implement DRM for camera and codecs.
- bri3d 3y ago
  ThreadX is just the scheduler / OS functionality. There are tons of other components in the firmware (namely, the parts that actually do things) which are still encumbered by patent and copyright issues, not to mention the DRM modules which are somewhat security-by-obscurity based. It's one step closer to an open Pi firmware in some ways, but probably not a meaningful step.
jylam 3y ago
Having worked (very) closely on GPU firmwares and drivers, I always find it funny that it is still something so closely guarded and protected. Honestly there isn't much to it. That's fairly regular code, not like futuristic algorithms. You won't find any novel rasterizing code or ways to order your commands or whatever, 99% of the interesting work is done by the GPU. You'll find basic or vaguely clever code to order lists and optimize the order of the commands, but that's it. I'm 95% sure that if AMD released their firmware and/or their drivers source code, NVidia wouldn't learn anything of value, they wrote the same stuff anyway. That's just sad \o/
- gary_0 3y ago
  This is really just the modern patent regime at work, isn't it? Any random problem a chip company SE or EE can solve in an afternoon can get that solution whisked past an overworked patent examiner. Now open-sourcing your basic code to "optimize the order of the commands" opens your company up to a hojillion-dollar lawsuit from a patent troll or any competitor that feels like going nuclear. Maybe the patent is BS but it'll take a multi-million-dollar lawsuit to prove it. It might not even be realistic that some jerk is going to search through 10 million lines of driver code looking for patent violations, but these are corporations we're talking about. They're twitchy when it comes to risk. So the source of insanity here is the broken patent system, isn't it? (I agree that while you get to write vaguely clever code, even specialized software dev is 99% perspiration.)
- sillywalk 3y ago
  I'm old enough to remember the Open Graphics Project, to create at least initially an FPGA graphics card, and use the money to make an ASIC. It died ~2011 https://en.wikipedia.org/wiki/Open_Graphics_Project https://en.wikipedia.org/wiki/Open_Graphics_Project

Zigurd 3y ago

Can confirm: same story for PowerVR. It's a double whammy: They want the driver licensing revenue and they are afraid of patent trouble.

jauntywundrkind 3y ago
I was going to point out that Linux 6.8 seems on target to be shipping pretty decent powervr drivers, but yeah, probably a huge massive chunk of the magic is in the firmware blob, which is closed as heck as usual for this industry. Both drivers & boob very recently dropped: https://www.phoronix.com/news/PowerVR-Firmware-Blob https://www.phoronix.com/news/PowerVR-Firmware-Blob I think though they're finally realized trying to charge people for drivers has made them a hated name & gotten them no where. GMA500 is a long awful wound on everyone & held Intel back from being much better at embedded than they could have been. Powervr has been one of those living embodiments of the phrase "expensive chips without good drivers are just expensive sand", or however it goes. So now this stuff hypothetically is going to start to be broadly usable (only on Linux underimited architrctures I guess? Since it's mostly binary blobs?).

MegaDeKay 3y ago

"Broadcom never opens up anything". True, but from a link in the related article from The Guardian [0] > Broadcom when they developed the original Videocore firmware bought a licence for ThreadX from the writer. AIUI, a lifetime licence, it never expires. No royalties or anything like that. Raspberry Pi have modified that firmware many many times over the last 10 years, but no royalties to pay. Many years later the writer of ThreadX sold the thing to Microsoft. So sounds like the RPi folks have a free hand over this firmware and they might be able to open it now? [0] https://forums.theregister.com/post/reply/4735439 https://forums.theregister.com/post/reply/4735439

joezydeco 3y ago
I believe it's wishful thinking. I wish all you RPi fans the best in your endeavor.
- robertlagrant 3y ago
  > I believe it's wishful thinking. Why?
- Andrex 3y ago
  Maybe a clean room recreation is possible? Or are those straws even further out of grasp...
  - bri3d 3y ago
    Sure, and it's been done: https://github.com/christinaa/rpi-open-firmware https://github.com/christinaa/rpi-open-firmware - but that doesn't involve ThreadX source, just some standard reverse engineering work. ThreadX is really the least interesting part of this whole operation in terms of the Raspberry Pi. It's very cool that ThreadX has been open sourced as it offers an additional battle tested and mature alternative to FreeRTOS for new projects. If they're able to get and maintain the various safety certifications for ThreadX under the Eclipse foundation, this could be game-changing in a very different space from the Pi. But in terms of reverse engineering or open sourcing the Raspberry Pi VideoCore blob, open source ThreadX is pretty much a non-event IMO.
seba_dos1 3y ago
FWIW, the firmware is how they implement DRM for camera and codecs.
bri3d 3y ago
ThreadX is just the scheduler / OS functionality. There are tons of other components in the firmware (namely, the parts that actually do things) which are still encumbered by patent and copyright issues, not to mention the DRM modules which are somewhat security-by-obscurity based. It's one step closer to an open Pi firmware in some ways, but probably not a meaningful step.

jylam 3y ago

Having worked (very) closely on GPU firmwares and drivers, I always find it funny that it is still something so closely guarded and protected. Honestly there isn't much to it. That's fairly regular code, not like futuristic algorithms. You won't find any novel rasterizing code or ways to order your commands or whatever, 99% of the interesting work is done by the GPU. You'll find basic or vaguely clever code to order lists and optimize the order of the commands, but that's it. I'm 95% sure that if AMD released their firmware and/or their drivers source code, NVidia wouldn't learn anything of value, they wrote the same stuff anyway. That's just sad \o/

gary_0 3y ago
This is really just the modern patent regime at work, isn't it? Any random problem a chip company SE or EE can solve in an afternoon can get that solution whisked past an overworked patent examiner. Now open-sourcing your basic code to "optimize the order of the commands" opens your company up to a hojillion-dollar lawsuit from a patent troll or any competitor that feels like going nuclear. Maybe the patent is BS but it'll take a multi-million-dollar lawsuit to prove it. It might not even be realistic that some jerk is going to search through 10 million lines of driver code looking for patent violations, but these are corporations we're talking about. They're twitchy when it comes to risk. So the source of insanity here is the broken patent system, isn't it? (I agree that while you get to write vaguely clever code, even specialized software dev is 99% perspiration.)
sillywalk 3y ago
I'm old enough to remember the Open Graphics Project, to create at least initially an FPGA graphics card, and use the money to make an ASIC. It died ~2011 https://en.wikipedia.org/wiki/Open_Graphics_Project https://en.wikipedia.org/wiki/Open_Graphics_Project