Hi,
I'm facing the same question, since I ran into an issue where ubifs patches were need that were only merged into mainline at v4.9.
Hence, one can either try to backport those into v4.1, or try to just go to mainline.
As time progresses, this issue (of the v4.1 lagging behind) becomes worse. NXP/freescale itself also eventually will have to release a newer BSP for its processors anyway, so this is also relevant from NXP.
I did look around already, and quite some stuff has been merged to mainline (and alot of stuff hasn't).
A small summary of my (1 day) experience with mainline v4.11 and the IMX6ULL (I don't use yocto, just bare kernel compilation and some basic NFS rootfs):
- IMX6ULL boots with default config and dts for the evk
- Extremly slowly, because someone left a dev option on PROVE_LOCKS in the default config
- The spi-imx driver is different.. But you can port the one from v4.1 easily (don't forget the DTS entries for DMA)
- The gpmi (NAND) is different, but seems to work. I had to find out about the fsl,use-minimum-ecc option to get it to do the same as the v4.1
- 700/800 Mhz targets don't seem to be supported. There were some yocto patches that read fuses for this, but this is clearly not in mainline.
As NXP should make a new BSP at one point, it would be very interesting follow any stabilization branch in which this is done. That way I / anyone can see if any important patches come around, and already take them in (or actually try to get upstreamed). Is this branch already available? Is there like an overview of what is merged/ what not?
Thanks for any feedback!
Arnout
