Re: [Buildroot] [PATCH 4/7] package/mali-bifrost-driver: new package

On 30/12/21 17:08, Thomas Petazzoni wrote:

Hello,

On Thu, 30 Dec 2021 16:28:57 +0100
Giulio Benetti [off-list ref] wrote:

quoted

I had no chance to test it on real hardware for lack of time :-/ so I
don't know if it works, and it should not be expected to work. I've
compared r8 version of midgard against bifrost and they are pretty
different.

I'm pretty sure it works, since I've seen myself the patches from
Miquèl allowing to run Qt5/OpenGL on a Rockchip PX30 platform. I'm
questioning the terminology/choice of naming.

Ok. Probably Midgard and Bifrost have lot in common on driver side and 
that's why it works. PX30 has a G31-2EE which is a Bifrost:
https://developer.arm.com/ip-products/graphics-and-multimedia/mali-gpus/mali-g31-gpu

So ok, it works but it should be changed. What I can do is providing the 
bifrost driver with the patches for Midgard ported against Bifrost and 
ask the PR. But I don't have time to test and I don't have a working 
PX30 BR defconfig for PX30-Mini-Evb or Engicam PX30 board that I wanted 
to provide.

quoted

I'm working on this patchset in spare time[1] with the goal to create a
single mali-driver package to deal with Utgard, Midgard and Bifrost.
I've already requested to change repository name from
mali-bifrost-driver to mali-driver and it's been done plus merging
patches to allow building with up to Linux 5.15[2].

Ah, we did this rename?

Yes:
https://github.com/bootlin/mali-driver

quoted

Thomas, do you want me to send the v2 patchset in[1] to Buildroot
mailing list? It's not complete at all, but it's some step forward.

I'm a bit lost with all these renames. We already have
sunxi-mali-mainline-driver in the tree, which points to
https://github.com/mripard/sunxi-mali. I'm not sure which kernel driver
handles which GPU variant.

mripard/sunxi-mali[1] only deals with Mali Utgard for Sunxi.
The problem is that the mripard/sunxi-mali has a specific platform 
implementation for sunxi:
https://github.com/mripard/sunxi-mali/blob/master/patches/0005-mali-Add-sunxi-platform.patch

While bootlin/mali-driver[2] doesn't have any platform-specific 
implementation. As you've pointed you've tested PX30(Bifrost G31) and it 
works, so that means that G31 doesn't need any specific 
platform-specific implementations. BUT there is 
CONFIG_MALI_PLATFORM_NAME that can be used to point to platform-specific 
implementation(i.e. sunxi):
https://github.com/bootlin/mali-driver/blob/master/r8p0/drivers/gpu/arm/midgard/Kconfig#L72-L79

So what we can do is to add that Sunxi implementation to r6p2 and r8p1 
while adding them to bootlin/mali-driver[2] and remove the actual 
sunxi-mali-mainline-driver BR package.

That way we will end up(for the moment) with these packages:
A1) mali-driver => with all Utgard(Sunxi platform included), Midgard, 
Bifrost versions.
A2) sunxi-mali-mainline => that should change into sunxi-mali-utgard, 
check pending patches[3] for this. And as a second step I would call it 
mali-blobs-sunxi and try to have access from Allwinner to other Blobs 
with license(because I have access to G31 Sunxi blobs but I can't 
publish them) collecting there all Sunxi mali blobs(Utgard, Midgard, 
Bifrost)
A3) mali-blobs-rockchip => with all Rockchip blobs(Utgard, Midgard, 
Bifrost) that we can easily take from rockchip-linux/libmali

This way it becomes easy to add other SoCs drivers and blobs. Steps 
would be:
B1) add platform specific implementation to bootlin/mali-driver(if any)
B2) waiting for PR to be merged
B3) add Buildroot package for the blobs with dependencies on mali-driver 
like mali-blobs-newSoc

Said this, the problem is time for me.

Hope everything is clear.

[1]: https://github.com/mripard/sunxi-mali
[2]: https://github.com/bootlin/mali-driver
[3]: https://patchwork.ozlabs.org/project/buildroot/list/?series=270656

Best regards
-- 
Giulio Benetti
Benetti Engineering sas
_______________________________________________
buildroot mailing list
buildroot@buildroot.org
https://lists.buildroot.org/mailman/listinfo/buildroot