Reverse Engineering & Open-Source Driver Work Advancing For Arm's Valhall GPU

[phoronix]

Phoronix: Reverse Engineering & Open-Source Driver Work Advancing For Arm's Valhall GPU

The Arm Mali Valhall architecture reverse-engineering started last summer and while limited in the reverse engineering capabilities for several months, it looks like by this summer we'll hopefully see a working driver for Arm's newer graphics IP...

https://www.phoronix.com/scan.php?page=news_item&px=Valhall-Early-2022-Progress

[bezirg]

Amazing work again by Alyssa and the rest! Personally I am looking forward to a recently announced arm sbc that will come with linux (radxa rockpi 5 with rockchip rk3588 and valhall gpu).

[Developer12]

The process she applied on the android phone sounds a lot like the one she used to develop a userspace macos M1 gpu driver.

[Quackdoc]

This made me chuckle a bit

This change is the embodiment of a “fix everything” magic bit, the kind only rumoured to exist and the stuff of reverse-engineers’ nightmares.

…But setting that bit in our kernel makes our null job complete successfully.

…Wait, what?

[peterdk]

How does that work with a chromebook with that new GPU? Does ARM provide a binary driver for Chrome OS?

[Quackdoc]

How does that work with a chromebook with that new GPU? Does ARM provide a binary driver for Chrome OS?

not arm, but mali, and yes. chrome os is based on chromium OS, same thing with how the greater android OS is based on AOSP. they work in much a similar way

[blackshard]

not arm, but mali, and yes. chrome os is based on chromium OS, same thing with how the greater android OS is based on AOSP. they work in much a similar way

small punctuation: ARM provides drivers for Mali GPUs, since Mali is their GPU lineup

[nranger]

Can we get Linus to flip off ARM on camera please? I get that their Linux support has greatly improved over the past decade (board support files, ewww), and they don't make silicon themselves, but all these closed drivers, and the mess of platform specific code just doesn't make sense for the OS that powers 90% of their installed base.

C'mon ARM, do better. Alyssa, keep up the great work.

[archsway]

How does that work with a chromebook with that new GPU? Does ARM provide a binary driver for Chrome OS?

Well, Arm provides (under a restrictive licensing agreement) the source for a generic Linux driver, and then Google customises it for Chrome OS, then they compile it themselves and make it available for download for use in the board-specific build scripts, for example:

http://commondatastorage.googleapis.com/chromeos-localmirror/distfiles/mali-drivers-valhall-cherry-25.0_p6.run

[libv]

The process she applied on the android phone sounds a lot like the one she used to develop a userspace macos M1 gpu driver.

Since it is the exact same thing done on Android 2.3 on telechips back in 2011, quite likely recycling the same code still.