BSP 2.8b2 Fails to Load Linux Kernel Due to uImage vs. zImage Kernel Image Format

I updated to the SOM to the BSP 2.8b2 from an older image version.

Now U-Boot fails to load the Linux kernel with the following output:

U-Boot 2016.11-2.8.2+ge9cabb6 (Feb 07 2018 - 12:41:04 +0000)

TEGRA124
DRAM:  2 GiB 
MMC:   Tegra SD/MMC: 0, Tegra SD/MMC: 1, Tegra SD/MMC: 2
In:    serial
Out:   serial
Err:   serial
Model: Toradex Apalis TK1 2GB V1.2A, Serial# 02997331
Net:   No ethernet found.
Hit any key to stop autoboot:  0
Booting from internal eMMC chip...
reading tegra124-apalis-v1.2-eval.dtb
67555 bytes read in 16 ms (4 MiB/s)
reading uImage
** Unable to read file uImage **
MMC: no card present
switch to partitions #0, OK
mmc0(part 0) is current device
Scanning mmc 0:1...
starting USB...
USB0:   USB EHCI 1.10
USB1:   USB EHCI 1.10
USB2:   USB EHCI 1.10
scanning bus 0 for devices... 1 USB Device(s) found
scanning bus 1 for devices... 1 USB Device(s) found
scanning bus 2 for devices... 1 USB Device(s) found

USB device 0: unknown device
e1000: no NVM
e1000: e1000#0: ERROR: Valid Link not detected: -8
missing environment variable: pxeuuid
missing environment variable: bootfile
Retrieving file: pxelinux.cfg/01-00-14-2d-2d-bc-53
e1000: e1000#0: ERROR: Valid Link not detected: -8
missing environment variable: bootfile
Retrieving file: pxelinux.cfg/C0A80A02
e1000: e1000#0: ERROR: Valid Link not detected: -8
missing environment variable: bootfile
Retrieving file: pxelinux.cfg/C0A80A0
e1000: e1000#0: ERROR: Valid Link not detected: -8
missing environment variable: bootfile
Retrieving file: pxelinux.cfg/C0A80A
e1000: e1000#0: ERROR: Valid Link not detected: -8
missing environment variable: bootfile
Retrieving file: pxelinux.cfg/C0A80
e1000: e1000#0: ERROR: Valid Link not detected: -8
missing environment variable: bootfile
Retrieving file: pxelinux.cfg/C0A8
e1000: e1000#0: ERROR: Valid Link not detected: -8
missing environment variable: bootfile
Retrieving file: pxelinux.cfg/C0A
e1000: e1000#0: ERROR: Valid Link not detected: -8
missing environment variable: bootfile
Retrieving file: pxelinux.cfg/C0
e1000: e1000#0: ERROR: Valid Link not detected: -8
missing environment variable: bootfile
Retrieving file: pxelinux.cfg/C
e1000: e1000#0: ERROR: Valid Link not detected: -8
missing environment variable: bootfile
Retrieving file: pxelinux.cfg/default-arm-tegra124
e1000: e1000#0: ERROR: Valid Link not detected: -8
missing environment variable: bootfile
Retrieving file: pxelinux.cfg/default-arm
e1000: e1000#0: ERROR: Valid Link not detected: -8
missing environment variable: bootfile
Retrieving file: pxelinux.cfg/default
e1000: e1000#0: ERROR: Valid Link not detected: -8
Config file not found
e1000: e1000#0: ERROR: Valid Link not detected: -8
Apalis TK1 # 

How can I make U-Boot properly loading the kernel again?

With the BSP 2.8b2 we switched from the legacy U-Boot specific uImage format to the generic compressed Kernel image type (zImage).

The U-Boot environment must be changed to take that into account, but, to not override settings you might have in the environment we do not reset it automatically.

If you do not want to keep the environment set it to the new defaults as follows:

env default -a
saveenv

If you want to keep your environment, first print the two affected variables for your records, then set them to their new values:

printenv boot_file emmcboot
env default boot_file emmcboot
saveenv