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

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

QuadXPlus

2GB

RevC

u-boot-ccimx8xsbcpro2GB-C0.imx

ccimx8x_sbc_pro2GB_android_defconfig

RevB

u-boot-ccimx8xsbcpro2GB-B0.imx

With Trusty support:

CPU type RAM size SOC revision U-Boot file U-Boot defconfig

QuadXPlus

2GB

RevC

u-boot-ccimx8xsbcpro2GB-C0-trusty.imx

ccimx8x_sbc_pro2GB_android_trusty_defconfig

RevB

u-boot-ccimx8xsbcpro2GB-B0-trusty.imx

Check your variant CPU, SOC revision, and RAM size on the serial console boot log:

U-Boot SPL dub-2020.04-r2.2 (Jan 18 2021 - 15:54:04 +0000)
Normal Boot
Trying to boot from MMC1
Primary set selected
Load image from MMC/SD 0x5f400


U-Boot dub-2020.04-r2.2 (Jan 18 2021 - 15:54:04 +0000)

CPU:   NXP i.MX8QXP RevB A35 at 1200 MHz at 25C
DRAM:  2 GiB
MCA:   HW_VER=1  FW_VER=1.01
MMC:   FSL_SDHC: 0, FSL_SDHC: 1
In:    serial
Out:   serial
Err:   serial
Model: Digi International ConnectCore 8X SBC Pro Board.
ConnectCore 8X SOM variant 0x02: 2 GiB LPDDR4, Wi-Fi, Bluetooth, MCA, Crypto-auth
  Board version 3, ID 135
Boot:  MMC0

 BuildInfo:
  - SCFW 56682d58, SECO-FW 0e4b9cee, IMX-MKIMAGE 8da5cd23, ATF c949a88
  - U-Boot dub-2020.04-r2.2

flash target is MMC:0
Net:   eth0: ethernet@5b040000 [PRIME], eth1: ethernet@5b050000
Fastboot: Normal
Normal Boot
Hit any key to stop autoboot:  0
=> 
NXP released two revisions of the SOC silicon: revision B0 and revision C0. See SOC revisions for more information.