Can I Run STM32MP157 without OS?

[yakabmarci]

yes

[Tesla DeLorean]

It is a micro-controller, it will run whatever you feed it.

UBOOT presumably is just code. Examine how it, and the prior loader, start the system and bring up the memories, and hand control to the OS.

Usually the OS that deals with the memory virtualization.

Will however require you to fully read and understand the manuals, and the peripherals described in the RM, and the circuit as implemented on the board.

[李林.1312]

Thanks! But how to use GPU, there is no doc to reference. such as regster of GPU.

[Tesla DeLorean]

Perhaps not publicly, ST uses assorted IP licensed from third-parties and have NDA restrictions, you'll likely have to obtain from Vivante directly yourself

[PatrickF]

GPU is unlikely to be supported outside Linux/Android. Driver is provided as binary by Vivante and there is no available documentation to have bare-metal use of GPU.

Maybe you could mention your use cases requiring to use a Cortex-A7 without OS. Maybe using an MCU like STM32H7 could be more appropriate.