AnsweredAssumed Answered

Boot M4 automatically on i.MX6 SoloX SABRE-SDB

Question asked by Jason Queen on May 3, 2017
Latest reply on May 30, 2017 by Carlos_Musich

Hi there, 


I am trying to get the M4 core to boot before the A9 core on the i.MX6 SoloX SABRE-SDB. It is important for me to have the M4 boot quickly and then have the A9 follow. I have successfully developed a FreeRTOS application for the M4 which only utilities FlexCan to communicate to other devices. When I boot the M4 manually in uboot everything works perfectly. However, when I try boot the M4 automatically before the A9 then the application works fine until the A9 begins to boot into Linux.


I have added the following variable to uboot which I use to boot the M4 core with my application:

   startm4=fatload mmc 2:1 0x80000000 driver_control_code.bin; dcache flush; cp.b 0x80000000 0x7F8000    0x8000; dcache flush; bootaux 0x7F8000;


I have changed the the following variables in uboot (changes are in bold):

   fdt_file = imx6sx-sdb-m4.dtb


   bootcmd=mmc dev 2;mmc dev 2; if mmc rescan; then if run loadbootscript; then run bootscript; else if run loadimage;    then run startm4; run mmcboot; else run netboot; fi; fi; else run netboot; fi


   mmcargs=setenv bootargs uart_from_osc console=${console},${baudrate} root=${mmcroot}


Any advice on how to automatically boot the M4 before the A9 correctly?