Rockchip RK3399 (ROCKPro64) boots to multiuser

[Greg V]

Hi,

I managed to boot FreeBSD on the Rockchip RK3399 SoC (Pine64 ROCKPro64 
board):

https://gist.github.com/myfreeweb/5f5b9e56f9a0fd1d63a46c34886f5ad1

As with the ROCK64, boot is over the network. To boot, dd ayufan's 
ubuntu image onto an sdcard and Ctrl-C the linux boot on the kernel 
selection screen. U-Boot on SPI flash is not available yet.

Unfortunately, performance is very disappointing — I think the big 
cluster's default frequency is very low.
(Everything runs faster if cpuset to the LITTLE cores.)

Looks like we'll need a driver for the "rockchip,rk808" PMIC to make 
cpufreq_dt work…
Also my attempt at the clock driver is very incomplete ;)