Display Board Spec:
Documents list: Layout Design Guide_V0.4.pdf RK3399 layout requirements of interfaces.xlsx RK3399_IO_LIST_V12_for EVB&REF&Excavator-20170111.pdf RK3399_SOC-package_PIN_DELAY_0V2.pdf RK3399_conductor_length_v1.0.xls RK3399_hardware_design_guide_V1.1_20170112(Chinese).pdf Rock-chips_PDN_Design_Guide_V0.2 .pdf
Refer Rockchip Open Source Wiki for more information.