The following table lists the U-Boot file associated with each ConnectCore 8M Mini variant:

Only platforms with 2 GiB RAM or more are supported.
RAM size U-Boot file U-Boot defconfig

2GB

u-boot-ccimx8mmdvk.imx

ccimx8mm_dvk_android_defconfig

With Trusty support:

RAM size U-Boot file U-Boot defconfig

2GB

u-boot-ccimx8mmdvk-trusty.imx

ccimx8mm_dvk_android_trusty_defconfig

Check your variant RAM size on the serial console boot log:

U-Boot SPL dub-2020.04-r3.1-git-00114-g909871f6fff7-dirty (Feb 11 2021 - 16:54:47 +0100)
DDRINFO: start DRAM init
DDRINFO: DRAM rate 3000MTS
DDRINFO:ddrphy calibration done
DDRINFO: ddrmix config done
Normal Boot
Trying to boot from MMC2


U-Boot dub-2020.04-r3.1-git-00114-g909871f6fff7-dirty (Feb 11 2021 - 16:54:47 +0100)

CPU:   i.MX8MMQ rev1.0 1600 MHz (running at 1200 MHz)
CPU:   Industrial temperature grade (-40C to 105C) at 32C
Reset cause: POR
DRAM:  2 GiB
MCA:   HW_VER=1  FW_VER=1.00
MMC:   FSL_SDHC: 1, FSL_SDHC: 0
In:    serial
Out:   serial
Err:   serial
Model: Digi ConnectCore 8M Mini Development Kit
ConnectCore 8M Mini SOM variant 0x03: 2 GiB LPDDR4, Wi-Fi, Bluetooth, MCA, Crypto-auth
  Board version 3, ID undefined
Boot:  MMC2

 BuildInfo:
  - ATF a7f57f3
  - U-Boot dub-2020.04-r3.1-git-00114-g909871f6fff7-dirty

flash target is MMC:0
Net:   eth0: ethernet@30be0000
Fastboot: Normal
Normal Boot
Hit any key to stop autoboot:  0
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