arm on Tinker Board (rk3288) - currently broken?

Hello,

I've seen a number of recent commits for the rk3288 SoC, so I dug out my
Tinker Board and tried to install the latest snapshot (miniroot dated
27-Sep-2019 06:14).

I followed the updated directions for this chip:

For systems based on Rockchip RK3288 SoCs:

dd if=/usr/local/share/u-boot/board/idbloader.img \
of=/dev/sdXc seek=64
dd if=/usr/local/share/u-boot/board/u-boot.img \
of=/dev/sdXc seek=16384

Unfortunately, when I try to boot, I get:

rying to boot from BOOTROM
Returning to boot ROM...

U-Boot SPL 2019.07 (Sep 25 2019 - 20:12:08 -0600)
Trying to boot from MMC1
spl: mmc init failed with error: -110
SPL: failed to boot from all boot devices
### ERROR ### Please RESET the board ###

Is this currently known to be broken, or am I doing something wrong?

Thanks,

--

Joe Gidi
joe@entropicblur.com

"You cannot buy skill." -- Ross Seyfried