Note: A lot of the information here was taken from Collabora’s RockPi4 repository.

ROCK Pi 4 is a Rockchip RK3399 based SBC (Single Board Computer) by Radxa.

There are three variants: A, B and C. With the main difference being the presence of WiFi and Bluetooth on B and C, and the presence of DP and HDMI mini on C. More information on https://wiki.radxa.com/Rockpi4/getting_started.

Specification:

  • Rockchip Rk3399 SoC
  • 2x ARM Cortex-A72 @ 1.8GHz, 4x ARM Cortex-A53 @ 1.4GHz
  • 1/2/4GB memory
  • Mali T860MP4 GPU
  • MIPI CSI 2 lanes connector
  • eMMC module connector
  • uSD slot (up to 128GB)
  • 4x USB
  • 1x HDMI
  • Ethernet port
  • 40-pin IO header including UART, SPI, I2C and 5V DC power in
  • USB PD over USB Type-C
  • Size: 85mm x 54mm

This board is available from Radxa distributors.

Power control

The board can be powered on with 5V via pins 2 or 4 in the GPIO header (as shown in the GPIO pinout), and GND on pin 6 for example. The pins are colored accordingly on the latest board revision:

Power through GPIO

Alternatively, the board can be powered via a USB PD Type-C connector:

  • 9V/2A, 12V/2A, 15V/2A, 20V/2A

Low-level boot control

Serial connection on the board can be done through pins on the GPIO. The board’s TX is on pin 8 and RX on pin 10 as per the pinout. Serial specification:

  • 3.3V TTL
  • 1500000 8n1

Serial through GPIO

Network connectivity

There’s a standard Gigabit Ethernet port on the board that can be used.

Bootloader

For the bootloader setup, a ready-to-use image is available at Collabora’s Rock Pi 4 repository as an artifact from the CI. In addition to u-boot (and idbloader and trust img), it also contains a kernel and rootfs, but after flashing and dropping to the u-boot prompt, tftp and nfs can be configured to retrieve the kernel and rootfs, ignoring the ones flashed.

Load addresses:

  • Kernel: 0x280000
  • DTB: 0x8300000
  • Ramdisk: 0xa200000

The main bootloader is stored in eMMC.

Health checks

Mainline kernel and defconfig don’t have working NFS. For that, this custom config can be used with mainline v5.12 kernel.

Lab notes and trouble shooting

None.