4.25. Rockchip RK3188

4.25.1. Radxa Rock

Radxa Rock is a small SBC based on Rockchip RK3188 SoC. See http://radxa.com/Rock for additional information.

4.25.1.1. Building

make ARCH=arm radxa_rock_defconfig
make ARCH=arm

4.25.1.2. Creating bootable SD card

This will require a DRAM setup blob and additional utilities, see above.

Card layout (block == 0x200 bytes).

Block Number

Name

0x0000

DOS partition table

0x0040

RK bootinfo (BootROM check sector)

0x0044

DRAM setup routine

0x005C

Bootloader (barebox)

0x0400

Barebox environment

0x0800

Free space start

Instructions.

4.26. Rockchip RK356x

Barebox features support for the Rockchip RK3566 and RK3568 SoCs, where the RK3566 can be considered as reduced but largely identical version of the RK3568.

4.26.1. Supported Boards

  • Rockchip RK3568 EVB

  • Rockchip RK3568 Bananapi R2 Pro

  • Pine64 Quartz64 Model A

  • Radxa ROCK3 Model A

  • Radxa CM3 (RK3566) IO Board

  • Protonic MECSBC

The steps described in the following target the RK3568 and the RK3568 EVB but generally apply to both SoCs and all boards. Differences between the SoCs or boards are outlined where required.

4.26.2. Building

The build process needs three binary files which have to be copied from the rkbin https://github.com/rockchip-linux/rkbin repository to the barebox source tree:

cp $RKBIN/bin/rk35/rk3568_bl31_v1.44.elf firmware/rk3568-bl31.bin
cp $RKBIN/bin/rk35/rk3568_bl32_v2.15.bin firmware/rk3568-bl32.bin
cp $RKBIN/bin/rk35/rk3568_ddr_1560MHz_v1.23.bin arch/arm/boards/rockchip-rk3568-evb/sdram-init.bin

With these barebox can be compiled as:

make ARCH=arm rockchip_v8_defconfig
make ARCH=arm

Note

When compiling OP-TEE yourself, use the tee.bin image as it has a header telling barebox where to load the image to. The tee-raw.bin image lacks a header and thus barebox will fallback to the hardcoded addresses expected by the vendor blobs in the rkbin repository.

Note

The RK3566 and RK3568 seem to share the bl31 and bl32 firmware files, whereas the memory initialization blob is different.

Note

The bl31 from the rkbin repository seems to be unable to handle device trees of a larger size (for example, if CONFIG_OF_OVERLAY_LIVE is enabled). Disable CONFIG_ARCH_ROCKCHIP_ATF_PASS_FDT in this case.

4.26.3. Creating a bootable SD card

A bootable SD card can be created with:

dd if=images/barebox-rk3568-evb.img of=/dev/sdx bs=1024 seek=32

The barebox image is written to the raw device, so make sure the partitioning doesn’t conflict with the are barebox is written to. Starting the first partition at offset 8MiB is a safe bet.

4.26.4. USB bootstrapping

The RK3568 can be bootstrapped via USB for which the rk-usb-loader tool in the barebox repository can be used. The tool takes the same images as written on SD cards:

./scripts/rk-usb-loader images/barebox-rk3568-evb.img

Note that the boot order of the RK3568 is not configurable. The SoC will only enter USB MaskROM mode when no other bootsource contains a valid bootloader. This means to use USB you have to make all other bootsources invalid by removing SD cards and shortcircuiting eMMCs. The RK3568 EVB has a pushbutton to disable the eMMC. On the Quartz64 boards, remove the eMMC module if present.

4.26.5. Console Output

The DDR-init in the rkbin repository will set up a serial console at 1.5 MBaud, while barebox will set up the console with the baudrate it has been configured with in DT and/or Kconfig, which may be different.

It can be useful for debugging to have the same baudrate for all components.

The barebox baudrate is defined by device tree:

/ {
  chosen {
    stdout-path = "serial0:1500000n8";
  };
};

and CONFIG_BAUDRATE controls the default if no baud rate is specified or the device tree has not been parsed yet:

$ scripts/config --file .config --set-str CONFIG_BAUDRATE 1500000

The DDR-init baudrate can be modified by setting a uart baudrate override in the ddrbin_param.txt file in the rkbin repository:

diff --git a/tools/ddrbin_param.txt b/tools/ddrbin_param.txt
index 0d0f53884a72..f71e09aafc4c 100644
--- a/tools/ddrbin_param.txt
+++ b/tools/ddrbin_param.txt
@@ -11,7 +11,7 @@ lp5_freq=

 uart id=
 uart iomux=
-uart baudrate=
+uart baudrate=115200

 sr_idle=
 pd_idle=

And after that the ddrbin_tool binary can be used to apply this modification to the relevant ddr init blob:

$ tools/ddrbin_tool rk3568 tools/ddrbin_param.txt bin/rk35/rk3568_ddr_1560MHz_v1.21.bin