i.MX ProcessorsのトピックChanging kernel start address

Changing kernel start address

dogisfat — Tue, 15 Apr 2025 19:58:08 GMT

I have implemented the change detailed in Application note AN5127 (https://www.nxp.com/docs/en/application-note/AN5127.pdf) successfully for a i.MX7D platform with kernel 4.9. I am trying to update to a Yocto Kirkstone based BSP with kernel 5.10 and am failing to successfully boot when making the same modifications. The system gets stuck after printing "Staring Kernel ..."

What changes should I be aware of that will require additional changes to the kernel to get the modifications working for Kernel 5.10?

Re: Changing kernel start address

JosephAtNXP — Wed, 16 Apr 2025 20:40:22 GMT

Hi,

Thank you for your interest in NXP Semiconductor products,

If it fails when specifying the kernel address, what happen if you don't and flash a fresh build?

Regards

Re: Changing kernel start address

dogisfat — Wed, 16 Apr 2025 21:11:01 GMT

If the modifications detailed in the application note are not implemented the kernel boots and functions normally.

Re: Changing kernel start address

dogisfat — Thu, 24 Apr 2025 21:51:32 GMT

I have narrowed the failure to boot to be in the __turn_mmu_on function in arch/arm/kernel/head.S. Unfortunately the comment for __turn_mmu_on specifies that you cannot trace through this function which I assume applies to jtag debuggers. I also have been unable to print to the UART though it (unsurprisingly).

What do I need to verify prior to that call to ensure the platform is correctly set up?