I wouldn't generalize Rockchip as good. You're lucky if they release one volume of their six volume reference manual, with "Confidential" plastered all over, a

I wouldn't generalize Rockchip as good. You're lucky if they release one volume of their six volume reference manual, with "Confidential" plastered all over, and most peripherals completely undocumented beyond vague register names. If you're extra lucky, you'll find another leaked volume on a sketchy Chinese website. Anything else? NDA. And what about new chips? Look up datasheets for e.g. the (now popular) RK3566. You get a 58 page document which is just a general overview plus pinout and not much else. Does fuck all for you if you actually want to write drivers and get the thing to work.