Part Number: TM4C1294NCPDT
In SW-TM4C-BOOTLDR-UG-2.2.0.295 (file named "SW-TM4C-BOOTLDR-UG-2.2.0.295.pdf"), in chapter "4. Ethernet Update", in sentence
"The Ethernet controller will be configured to use the MAC address stored in the USER0/UART1 data registers..."
I would replace "UART1" with "USER1".
Best wishes,
Piotr Kasprzyk