sdcard boot fails for a derivative cm3 io board

[flatmax]

I have a custom pcb similar to the cm3 io board.

I have found that I get boot loop when I update the uboot version :
BR2_TARGET_UBOOT_CUSTOM_REPO_VERSION="26d3b6963ed2d2215348f1baba8b9646ed3dc6ea" # this newer version breaks sdcard booting
BR2_TARGET_UBOOT_CUSTOM_REPO_VERSION="19cefea3b8a7e22fa29b39367b04a8ab90c5c765" # this older version has a working sdcard boot

In the new version I get boot loop at this point :

vdd_cpu: supplied by vcc5v0_sys
rk808 0-0020: chip id: 0x8170
rk808 0-0020: No cache defaults, reading back from HW
rk808 0-0020: source: on=0x40, off=0x00
rk808 0-0020: support dcdc3 fb mode:-22, 63
rk808 0-0020: support pmic reset mode:0,0
... goes back to initial boot loader at this point ...

In the old version which boots successfully I get :

vdd_cpu: supplied by vcc5v0_sys
rk808 0-0020: chip id: 0x8170
rk808 0-0020: No cache defaults, reading back from HW
rk808 0-0020: source: on=0x40, off=0x00
rk808 0-0020: support dcdc3 fb mode:-22, 63
rk808 0-0020: support pmic reset mode:0,0
rk808-regulator rk808-regulator: there is no dvs0 gpio
rk808-regulator rk808-regulator: there is no dvs1 gpio
vdd_logic: supplied by vcc_sys
... snip ... continues to boot normally

To test this problem you should be able to switch the uboot repo version line above in this repo : https://github.com/flatmax/buildroot.rockchip/blob/master/configs/cm3_defconfig#L32

[RadxaYuntian]

Can you verify if 8818269 is the offending commit for your product?