Hi, I am working on a udoo neo board and i have my own m4 app. I have my own u-boot which loads the m4 binary and starts the m4 core, then it loads the kernel, dtb and rootfs and starts booting the a9 core. After linux boots, M4 core stops. I think the problem might because the kernel is trying to start the m4 core as well. Could anyone tell me how to modify the kernel in order to stop it from starting the m4 core?. Or any other ideas are welcome. More info: m4 binary is loaded in TCM memory Thank you
If your using the udoo ubuntu release then the m4 code is loaded after the kernel boots (not a good idea) this may be one possible cause of the problem. The kernel itself doesn't have the capability to load M4 code so the problem isn't there. The issue can be caused by a number of different issues so its difficult to provide you with a answer.
Maybe i can provide more info about the system, so i can get the root cause of the issue. The image that i am building is "core-image-minimal", so there is no other software that is interfering with the m4 core. The kernel is forked from https://github.com/fmntf/linux_kernel, branch 4.1.15_2.x-udoo In u-boot(forked from u-boot-imx, v2017.03), first the m4 code is copied into RAM then from there is copied into TCM at "0x7F8000", then m4 core boots. After this, the kernel, dtb are loaded and Linux starts. Linux addresses in u-boot: "kernel load address: LOADADDR=0x10008000" "fdt_addr=0x88000000" "fdt_addr_r=0x88000000" "kernel_addr_r=0x87000000" Maybe you have some other ideas?
