Here is the step-by-step to boot U-Boot on rv1108 evb.
Get ddr init binary
==============================================================================
> git clone https://github.com/rockchip-linux/rkbin.git
> dd if=./rkbin/rv1x/rv1108ddr.bin of=ddr.bin bs=4 skip=1
Compile U-Boot
===========================
> make CROSS_COMPILE=arm-linux-gnueabi- evb-rv1108_defconfig all
> ./tools/mkimage -n rv1108 -T rksd -d ddr.bin spl.bin
> cat spl.bin u-boot.bin > u-boot.img
Flash the image by rkdeveloptool
================================
rkdeveloptool can get from https://github.com/rockchip-linux/rkdeveloptool.git
Power on(or reset with RESET KEY) with MASKROM KEY preesed, and then:
> rkdeveloptool db ./rkbin/rv1x/RV1108_usb_boot.bin
> rkdeveloptool wl 0x40 u-boot.img
> rkdeveloptool RD
You should be able to get U-Boot log message from boot console:
DDR Version V1.02 20170220
In
400MHz
DDR3
Bus Width=16 Col=10 Bank=8 Row=15 CS=1 Die Bus-Width=16 Size=512MB
mach:2
OUT
U-Boot 2017.05-00693-g3a5b171 (Jun 01 2017 - 17:37:53 +0800)
Model: Rockchip RV1108 Evaluation board
DRAM: 128 MiB
APLL: 600000000 DPLL:792000000 GPLL:384000000
MMC:
Using default environment
In: serial@10210000
Out: serial@10210000
Err: serial@10210000
Net: No ethernet found.
Hit any key to stop autoboot: 0
=>
2d1951fec6