The following table lists the U-Boot file associated with each ConnectCore 6 Plus variant:

RAM size U-Boot file U-Boot defconfig

2GB

u-boot-ccimx6qpsbc2GB-2017.03-r0.imx

ccimx6qpsbc2GB_defconfig

1GB

u-boot-ccimx6qpsbc1GB-2017.03-r0.imx

ccimx6qpsbc1GB_defconfig

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

U-Boot dub-2017.03-r7.1 (Oct 02 2020 - 15:35:14 +0000)

CPU:   Freescale i.MX6QP rev1.1 at 792MHz
CPU:   Industrial temperature grade (-40C to 105C) at 38C
Reset cause: POR
I2C:   ready
DRAM:  2 GiB
MMC:   FSL_SDHC: 0, FSL_SDHC: 1
In:    serial
Out:   serial
Err:   serial
Model: Digi International ConnectCore 6 QuadPlus Single Board Computer.
ConnectCore 6 Plus SOM variant 0x02: Industrial QuadPlus-core 1GHz, 8GB eMMC, 2GB DDR3, -40/+85C, Wireless, Bluetooth, Kinetis
Board: ConnectCore 6 Plus SBC, version 3, ID 160
Boot device: MMC4
PMIC:  DA9063, Device: 0x61, Variant: 0x63, Customer: 0x00, Config: 0x90
Net:   FEC [PRIME]
Hit any key to stop autoboot:  0
=>