(01-04-2016, 01:53 PM)beard Wrote: For those who keep talking about 3.x Kernel versions forget them. We need to be looking at 4.x. Mostly at either 4.2.x or .4.4.x
Be prepared that 3.10.y is currently all you have. While it's relatively 'easy' to put together a rather huge patchset to get from 3.10.65 up to 3.10.94 (IIRC latest 3.10 LTS version -- 3.10 support has been discontinued a few days ago) to include maybe 1000-2000 fixes in the 3.10.y kernel series it won't help that much.
And also forget about 4.2.x, 4.4.x or 3.18 (as the Pine guys write in their FAQ). It works differently. In case you're interested watch the linux-sunxi ML: https://groups.google.com/forum/#!forum/linux-sunxi (it's a patch reviewing and development list, so please no NOOBs questions there. Silently monitor it if you're not familiar with kernel development at least for a few weeks to get an idea how this all works)
Read threads regarding H3, A83T and A64 to get an idea how long it might take until a new Allwinner SoC becomes useable with mainline u-boot/kernel ('useable' in a very basic meaning, read as: It boots on a single CPU core and stuff like UART, USB, maybe networking, maybe display, maybe SMP are working).
U-boot is a different story. The version Allwinner delivered with the A64 BSP still makes use of the sys_config.fex stuff (while the kernel already uses device tree -- 'nice' mixture
), that will never be accepted/used by mainline u-boot therefore this has also to be written from scratch.Regarding device drivers: It seems Allwinner implemented a new Ethernet core starting with H3 and re-uses it in A83T (also called H8/R58) and A64 (also called H64/R18). Code/efforts might be re-used but the ARMv7 vs. ARMv8 problem remains. I've no idea about other driver stuff since it seems none of the devs except a few had a closer look into A64 already. That might change with the availability of dev boards (Rev. B Pine64, Olimex) but I won't count on it. And I still wonder why the Pine guys didn't buy a few Remix Minis (also a Kickstarter campaign based on A64 and already shipping) and sent them to interested developers. 99% of work to get a recent Linux kernel running on the Pine64 is needed to support the A64 SoC regardless of the device in question.
BTW: In the last few weeks I've seen one single post here in the forums from a person that seems to know what he's talking about regarding Aarch64 and the steps necessary to get Linux running even just with Allwinner's 3.10.65 Android kernel (not to speak of Mainline kernel). And this is the very same guy now starting to submit patches to the linux-sunxi list to prepare mainline kernel support in the future.
(01-04-2016, 02:28 PM)joe Wrote: Do you know other new CPU kernel is use 3.x is not only allwinner
Please turn on CAPS lock also! That makes your valuable insights better readable!!!
Fortunately I've been able to read your question even if you just used bold type (it was hard though). Please check the official linux kernel github repository and there the master branch: https://github.com/torvalds/linux/tree/master/arch
There you might have a look into both arm/boot/dts (be prepared that the listing of devices with mainline kernel support is cut to 1,000 devices -- github really suckz!) and arm64/boot/dts (be prepared that you won't find an 'Allwinner' subdir there).
BTW: That you'll find there some companies actively providing mainline kernel support for their products is an (often unintentionally) byproduct of their business model. Rockchip for example actively contributes to mainline kernel not because they discovered their love for Open Source recently but since they were forced by Google (ChromiumOS) to do so. There's nothing comparable regarding Allwinner since their business model is to sell the SoCs for the cheapest Android gadgets available (where nobody cares about kernel version, conformance to GPL or code quality and the like. Only three other things count: cheap, cheap and cheap)