Hello @Aaran
I hope you are doing well.
I am not sure the content of your environment variables, but could you please try to set the complete command from the Getting Started with MCUXpresso SDK for EVK-MIMX8MP:
=> fatload mmc 1:1 0x48000000 hello_world.bin;cp.b 0x48000000 0x7e0000 20000;
=> bootaux 0x7e0000
Please try.
Best regards,
Salas.