In my new design with i.mx6q processor, user can not change the boot mode manually because the mainboard with ARM is installed in a box which not allowed to open. Then I have to find a way to change these boot mode pins in system.
I need to upload the new linux image to ARM by USB otg connect to PC, then dynamicly switch all boot modes to support emmc boot mode which is the normal boot mode. I can provide several GPIOs on a USB bridge chip which controlled by USB host as boot mode control pins.
This is a very original idea. Are these any guidence to support my solution? Simply, I need to connect USB cable to upload linux image to ARM, as soon as I disconnect the cable and restart the ARM, it should be boot from emmc.