[U-Boot] rk3288 (Tinkerboard) not booting

[Alexander von Gluck IV]

Anyone know a way to get a functional u-boot on the rk3288? (Tinkerboard, SD)

The docs seem to recommend:
$ /tmp/arm-build/tools/mkimage -n rk3288 -T rksd -d arm/tinkerboard/u-boot-spl-dtb.bin out

However, that produces:
Warning: SPL image is too large (size 0xb000) and will not boot

I saw this patch to disable I2C in the SPL to reduce its size:
https://github.com/xypron/u-boot-patches/blob/df2ceb65fb4cc433aa17304ed9d3d591c14ef5ac/0001-configs-tinker-rk3288-disable-CONFIG_SPL_I2C_SUPPORT.patch

However, that breaks the build :-|

 LD spl/u-boot-spl
arm-unknown-haiku-ld.bfd: drivers/built-in.o: in function `rk8xx_write':
/tmp/arm-build/drivers/power/pmic/rk8xx.c:30: undefined reference to `dm_i2c_write'
arm-unknown-haiku-ld.bfd: drivers/built-in.o: in function `rk8xx_read':
/tmp/arm-build/drivers/power/pmic/rk8xx.c:43: undefined reference to `dm_i2c_read'
make[1]: *** [scripts/Makefile.spl:404: spl/u-boot-spl] Error 1
make: *** [Makefile:1762: spl/u-boot-spl] Error 2
make: Leaving directory '/tmp/arm-build'
Disabling SPL Power then results in an error compiling MMC support
Any alternative methods to getting u-boot running from SD?
Rockchip devices seem to be kind of complex to get going :-|
 -- Alex