I can see I am going to have to understand uboot. I know older 8 bit processors would always start from a particular location in memory on power on. But the uboot I believe is called up from a ROM program which must be on the CPU chip itself. Is this the case if so how can I learn more about this ROM based program and what it does?
In the CV1835 Data Sheet it says the following:
The chip is booted by the built-in ROM (BOOTROM). When the chip is reset, it detects whether there is a weak pull-up or weak pull-down on two pins (SPINOR_MOSI, SPINOR_WP_X) to determine the type of memory device currently in use. So does that suggest that there is little or nothing of interest in the boot BOOTROM and it just jumps to external memory in which case which one?
It also goes on about secure boot. Would be interesting to know how this is all configured. I guess when I understand Uboot I may get an idea.