Cross platform high performance GPIO

[sgjava 77]

So my whole goal with java-periphery was to create a decent cross platform userspace IO library which I believe I have achieved. One of my other goals was to create a high performance GPIO API that's also cross platform. If you look around there aren't any from what I can tell. Most high performance GPIO libraries support only a few boards. What I've done is use a well known interface (GPIO device) and some MMIO code to detect deltas and generate the required resisters and masks from an input file. This surely beats doing this by hand which I tried at first. The result is code that supports Allwinner H2+/H3 and H5/H6 by using just an input file. I'm going to look at other CPU types next, but this is promising. For more info check out High performance GPIO using MMIO.