[U-Boot] help with serial on the rockchip64

Simon South simon at simonsouth.net
Tue Sep 24 22:08:22 UTC 2019

On 2019-09-24 5:41 p.m., Sérgio de Almeida Lenzi wrote:
> D:0x805 Y
> In
> 333MHz
 > ...

This is output from Rockchip's binary-only loader, which always resets 
the UART speed to 1.5Mbps. But it should be running before the U-Boot 
SPL, not after it.

How are you building the microSD-card image? Here are the commands I've 
been using to build working images for the ROCK64:

Building U-Boot (note this will overwrite your configuration with the 
contents of the defconfig file):

     make distclean; rm -f idbloader.img
     make rock64-rk2238_defconfig all u-boot.itb

Assembling an image with the Rockchip loader:

     tools/mkimage -n rk3328 -T rksd -d 
     cat spl/u-boot-spl.bin >> idbloader.img

Writing it to the microSD card:

     sudo dd if=idbloader.img of=/dev/mmcblk0 seek=64
     sudo dd if=u-boot.itb of=/dev/mmcblk0 seek=16384

Simon South
simon at simonsouth.net

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