how to let i.mx8 boot by cortex m4 only?

[monosail]

I want to test ddr4 chip by i.mx8m mini, because it has a ddr4 controller.

Here is my plan:

1. Run a cortex-m4 program on TCM to access ddr4 controller ( I cannot use linux because ddr4 dram is not available, I need ddr4 interface for testing the ddr4 chip).

2. Do not use cortex-a53 core.

And my question is: how can I boot the cortex-m4 directly (do not start cortex-a53)?

[igorpadykov]

Hi Mono

>my question is: how can I boot the cortex-m4 directly (do not start cortex-a53)?

I am afraid it is not possible as i.MX8M Mini boots only from cortex-a53.

Best regards
igor

[monosail]

Thank you! And I think I need to modify u-boot code to implement my ddr test function...

Where can I download the source code of u-boot for i.mx8 ?

[igorpadykov]

https://source.codeaurora.org/external/imx/uboot-imx/tree/board/freescale/imx8mm_evk?h=lf_v2021.04

Best regards
igor