Rockusb
Contents
Introduce
Rockusb is a vendor specific USB class from Rockchip, which is for firmware dowmload for Rockchip SoCs.
Get into Rockusb
There are two cases for Rockchip SoCs to get into Rockusb.
Maskrom mode
When there is no any firmware found on board, the SoC will run Rockusb driver automaticlly, we call it Bootrom mode or Maskrom mode.
If firmware is at somewhere of the board, in order to get into this mode, we can do something to prevent cpu read the firmware successful:
- for sd-card, unplug the sd-card;
- for eMMC, short the eMMC clock to GND;
- for NAND, short the data line or clock line;
- for SPI, short the spi signal to GND;
Bootloader mode
If you are using miniloader, which with Rockusb driver inside, system will run rockusb driver when recovery key is pressed.
USB ID
Rockchip Vendor ID is 0x2207, and the product ID for different SoCs are different.
Rockusb product ID:
- RK3288: 0x320a
- RK3328: 0x320c
- RK3399: 0x330c
Please use lsusb command in Linux PC to check if there is a Rockusb device connect.
Firmware download
rkdeveloptool is the tool to do the firmware upgrade for Rockchip SoCs which is using Rockusb protocol via USB.
Please follow the steps for boot from eMMC for how to use the tool.