On Tue, May 20, 2014 at 08:38:12PM +1000, Chris Samuel wrote:
Why not support FEX? Well basically because it's a reinvention of Device Tree, but badly designed.
to be fair, Allwinner's FEX was around before anyone decided that DT for Arm was the right way to go. IIRC DT in mainline was only for PPC at that time. the lwn article doesn't really point that out. BTW, from following sunxi-devel it seems DT has had to change a lot (and is still evolving) to support all the Arm SoCs out there. generalising is hard and slow work. I suspect FEX was probably the right solution for the company at the time, and it's certainly better than hardcoding everything like older Android kernels used to do. (as a data point my new qualcomm based phone runs a 3.4 kernel with DT) I'm reasonably hopeful my a10 DAC + backup, and a20 usb video cubies will be running mainline kernels in my lifetime :) cheers, robin
[1] - https://lwn.net/Articles/597916/ for other subscribers, free from Thursday when the next LWN comes out.