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An Update on Apple M1/M2 GPU Drivers

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71–80 of 291 posts

Re: An Update on Apple M1/M2 GPU Drivers

#71

> frankly, I think ray tracing is a bit of a gimmick feature That's incredibly arrogant. The whole industry is adopting ray tracing, and it is a very desired feature people are upgrading video cards to get working on games they play.

The M1-M4 GPUs are also nowhere close to fast enough for it to be useful. Just like Snapdragon having ray tracing support is ridiculous.

Re: An Update on Apple M1/M2 GPU Drivers

#72
post #48

Will M3/M4 need completely different drivers?

I think the answer is yes. I'm making assumptions based on this part of Alyssas talk a couple of weeks ago where she talks about M3 having specific driver support for raytracing which doesn't exist in previous versions. https://youtu.be/pDsksRBLXPk?t=2895 The whole thing is worth watching to be honest, it's a privilege to watch someone share their deep knowledge and talent in such an engaging and approachable way.

ooh, I missed this, thanks for the link!

Re: An Update on Apple M1/M2 GPU Drivers

#73

> tessellator.cl is the most unhinged file of my career ...so far. The presenter is only 23 apparently. Maybe I'm speaking only for myself here, but I think career unhingedness does not go down over time as much as one might hope. In all seriousness, she does really impressive work, so when she says this 2,000 lines of C++ is inscrutable, that gives one pause. Glad it's working nonetheless.

I guess it's these two files? The original 2600+ lines of C++: https://gitlab.freedesktop.org/asahi/mesa/-/blob/main/src/ga... The translated code: https://gitlab.freedesktop.org/asahi/mesa/-/blob/main/src/as...

Is there a blog post about what specifically she found to be inscrutable? The C++ doesn't look all that terse at a syntactic level, and has plenty of comments. Are the problems at the domain level?

Re: An Update on Apple M1/M2 GPU Drivers

#74
post #50

The work by Alyssa R and Asahi Lina is great stuff. I have to say that a lot of this is really inscrutable unless you’re used to driver code. I wish it were much easier to write this stuff but hardware stuff is so idiosyncratic. Have to say I do enjoy all the old school style whimsy with the witch costume and whatnot.

I've just been watching her recent talk. I noticed she appears to change slides with a wave of her wand. Is there an known piece of hardware one can purchase to do this? I tried googling, but trying to find the specific result I'm interested in amongst all the blog spam garbage related to powerpoint is beyond me. Even googles own AI couldn't help. Sad times!

Ug… a person is watching and clicking for her when she does that?

Re: An Update on Apple M1/M2 GPU Drivers

#75
post #25

Earlier quoted context omitted.

Major base changes, or just added more stuff on top of the same base?

M3 has mesh shader support. The geometry pipeline they inherited from PowerVR fundamentally doesn't support them, for reasons that go way over my head. They probably changed a good chunk of it.

> for reasons that go way over my head

In fairness to you I think a lot of the stuff involving hardware goes over everyone's heads :D

I've seen comments in a number of articles (and I think a few comments in this thread) saying that there are a few features in Vulcan/opengl/direct3d that were standardized ("standardized" in the D3D case?)/required that turned out to be really expensive to implement, hard to implement fast in hardware anyway, and not necessarily actually useful in practice. I think geometry shaders may have been one of those cases but I can't recall for sure.

Re: An Update on Apple M1/M2 GPU Drivers

#76
post #63
post #41

Earlier quoted context omitted.

OpenGL and Vulkan have tons of tests and Alyssa runs them. I don't know if it's automated through CI.

Reportedly, the lack of M3 support so far is because there is no M3 Mac Mini which they can use for CI.

That was one reason to delay it, but another more important they said was to implement gpu things like this and other missing features.

Re: An Update on Apple M1/M2 GPU Drivers

#77

I always wondered about these /SubscriberLink/ links. Is sharing them considered unethical?

I'm sure that they are very, very happy that HN is directing a firehose of traffic at their site on the regular.

In order to subscribe people need to know that LWN exists.

Re: An Update on Apple M1/M2 GPU Drivers

#78

I always wondered about these /SubscriberLink/ links. Is sharing them considered unethical?

Representatives of LWN have posted here before saying they are OK with it, along with a polite request not to have it go overboard since they need to fund the site and writers, editors, etc. That funding comes from subscriptions only IIUC. FWIW an LWN subscription is pretty affordable and supports some of the best in-depth technical reporting about Linux and linux-related topics available. (I am not affiliated with L…

Funding also comes from sponsors, as the article obviously states:

"I would like to thank LWN's travel sponsor, the Linux Foundation, for travel assistance to Montreal for XDC."

Re: An Update on Apple M1/M2 GPU Drivers

#79
post #37

Earlier quoted context omitted.

I wouldn't go so far as to say "mistake that should never have been standardized". Their intended use was always pretty limited, though. There's zero reason for anything built in recent memory to use them.

They had limited uses and turned out to be incredibly hard to implement efficiently in hardware, so in practice it was nearly always faster to just keep using the proven techniques that GS was supposed to replace. http://www.joshbarczak.com/blog/?p=667

And yet one of the fancy new features being advertised in recent years (in multiple APIs including Metal) is support for mesh shaders – which seem to have a lot in common with geometry shaders, including the output ordering property that that post blames for geometry shaders’ bad performance. I’m not a graphics programmer myself, but this makes me suspect there’s more to the story.
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