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A comment on AMD responds to Linux kernel maintainer's rejection of AMDGPU patch. Parent comment

Re:AMD responds to Linux kernel maintainer's rejection of AM... by zie on Friday December 09, 2016 @06:33PM (#13142838)
That's not true, really. Many vendors keep their own in-house patches to the mainline tree, that never make it upstream for various reasons(See Android's kernel for instance). There is nothing stopping a vendor or anyone else, from publishing their own linux tree that is a fork of mainline with this AMD patch applied. Linus maintains the 'mainline' tree, just because of the history and because most kernel hackers believe in their ability to run with it, but if Linus and friends ever did something horrid, there is nothing to stop some other group of people from forking and everyone moving to said new fork. That's part of the whole point of the GPLv2 and other OSS licenses.
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Re:AMD responds to Linux kernel maintainer's rejection of AM... by fapjacks on Friday December 09, 2016 @07:29PM (#13143145)
Right. And this is an indicator that the Good King and his generals have done an exemplary job keeping it solid: Everyone uses their product.
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Re:AMD responds to Linux kernel maintainer's rejection of AM... by izacus on Friday December 09, 2016 @07:41PM (#13143207)
Except the largest deployment of Linux in the world: Android devices.

Which are running a severely modified kernel because the process of going through mainline to get it mobile ready would be far too painful.

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Re:AMD responds to Linux kernel maintainer's rejection of AM... by AstralStorm on Saturday December 10, 2016 @02:23AM (#13144535)
Not really severely. It has a few questionable tweaks here and there.

The questionable part is CPU companies not pushing for upstream integration, so you get e.g. Qualcomm Linux. In fact, the process is not pushing, it is pulling. (some people have started working on it, still long way off)

It can be done, as shown by efforts by TI, ARM and many more...

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Re:AMD responds to Linux kernel maintainer's rejection of AM... by trome on Saturday December 10, 2016 @04:27AM (#13144861)
Hell, even Rockchip, Allwinner and Sony can do it, Qualcomm, Mediatek, Google and Samsung are just not doing it because they are able to skate by without doing it.

The funny part is on Windows Phone, Microsoft learned from the kernel development process and made Samsung, LG, HTC, et all upstream their drivers, whereas Google in the same position with the same vendors has not done this and thus Sony is the only OEM pushing drivers upstream.

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Re:AMD responds to Linux kernel maintainer's rejection of AM... by makomk on Saturday December 10, 2016 @07:30AM (#13145369)
Upstream Allwinner support is a community effort, and it takes so long to convince the kernel developers to merge code that parts are generally years obsolete by the time they're fully supported. I think the upstream support may almost be at the point that C.H.I.P could use it - but they're using a single-core SoC from early 2012. I've seen patches for basic functionality like clock controllers (without which nothing works) get stuck in endless mailing list arguments about the most elegant approach, contradictory requirements from different maintainers, all sorts. It's not working.

The kernels used by actual Allwinner-based Android devices have almost nothing in common with the upstream support. They use a completely different mechanism for describing the hardware configuration, a completely different set of drivers, and are based on a kernel that predates upstream support.

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Re:AMD responds to Linux kernel maintainer's rejection of AM... by trome on Saturday December 10, 2016 @11:51AM (#13146484)
True, but what has been accomplished with the Linux Sunxi community is a shortening of that loop to bring up new boards with modern kernels, the Pine A64 for example took only a year to gain support[1], and that was around the time they actually started shipping in quantity. Additionally, many of the ethernet drivers, HDMI PHY drivers, Cedrus (provides H.264 & H.265 decoding @ 10bit) are reusable on new chips like the H5[2].

I would not expect much from Allwinner directly, but at this point there is a sizable ecosystem and mainline support for most of their chips, which can't be said for most other ARM vendors. Another aspect of this is Allwinner sells most of their chips thru multiple business units, with the silicon being exactly the same, just what is silkscreened on the top of the package being different[3].

1 - http://www.cnx-software.com/2015/11/10/allwinner-a64-datashe... and https://forum.armbian.com/index.php/topic/1917-armbian-runni... 2 - http://www.cnx-software.com/2016/08/17/allwinner-h5-is-a-qua...

3 - https://forum.armbian.com/index.php/topic/2099-crypto-engine...

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Re:AMD responds to Linux kernel maintainer's rejection of AM... by makomk on Tuesday December 13, 2016 @08:24PM (#13173011)
The A64 was one of the chips whose clock controller support got stuck in mailing list hell for over a year. Currently that's planned for 4.10, basic stuff like Ethernet, USB and SD card support is still pending though: http://linux-sunxi.org/Linux_mainlining_effort I imagine they must be using a ton of patches on top of mainline to make that work.
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