Hello Tim, Some time ago I was adding MCUboot support for SAMv7 family that should be pretty similar to your system. If you can give some more description of your use case: RAM and ROM config, does it have internal flash or external, where the program is executed from, etc. maybe I will be able to help you.
Br, Petro On Wed, Jan 29, 2025, 11:59 AM Tim Hardisty <timhardist...@gmail.com> wrote: > Thanks for taking the time to reply, Lwazi. > > As best as I know, the Nuttx build (with my, or any app, set as the > start app) is running from RAM. Uboot certainly copies iteself to RAM > and runs - and if I get it it to load my build (which is smaller than > than the available ram) it works fine. > > I see from that arm_head.S has a #error if CONFIG_BOOT_RUNFROMFLASH is > set, which confuses me as I haven't knowingly done anything to build the > NuttX binary to specifically run from DRAM or in XIP mode. But I will > delve deeper, thanks. > > Related - I think the QSPI flash would need to be be put into XIP mode > to run that way so something else I can search for clues. Also I can > look at relocatable elf files etc which I know I've seen reference to. > > I also see that u-boot does a memcpy of the elf binary from flash to RAM > so examining that code further might also give me clues. > > If all else fails I will revert to using u-boot; I want(ed) to use > mcuboot as it natively supports iamge upgrades and swaps along with > encryption checks and seems to boot faster than uboot does. And I find > u-boot difficult to understand and work with, whereas mcuboot seemed > more "friendly"...until now lol. > > Thanks, > > TimH. > > On 29/01/2025 02:46, Lwazi Dube wrote: > > On Tue, 28 Jan 2025 at 13:30, Tim Hardisty <timhardist...@gmail.com> > wrote: > > > >> Hi all, > >> > >> I am trying to get MCUboot to work on my custom board with a SAMA5D2 > >> (Arm V7A) and after a lot of battles am nearly there. > >> > >> I can boot into MCUboot stored in flash, and I can also download/debug > it. > >> > >> MCUboot is happy enough with my firmware images to call my board's > >> "board_boot-image" function - but no SAMA5 boards in the repo have this > >> function for me to refer to. > >> > >> I have never used MCUboot. > > What happens if you jump into _vector_start at the beginning of the SAMA5 > > image? I presume that both your bootloader and nuttx are running XIP from > > NOR flash. > > The entry is _vector_start here -> arch/arm/src/arm/arm_vectortab.S > > ... and it jumps into __start here ->arch/arm/src/arm/arm_head.S > > Is this what you are looking for? > > >
