RE: using NVS on NET CPU

anthony32086 — Thu, 05 Aug 2021 18:47:08 GMT

Solved it, I ran some tests with the code changed to,

fs.offset = FLASH_AREA_OFFSET(storage) - DT_REG_ADDR(DT_CHOSEN(zephyr_flash));

then flashed with --recover to wipe all flash. Memory inspector on the NET core show both 0x0003a00 and 0x0103a00 addresses with 0xFFFFFFFF. Then after a nvs_write to id 1 memory inspector shows memory @ 0x0003a00 contains 0xFFFFFFFF however 0x0103a00 does show new data that was written.

It seems the nRF5340 does implicitly translate writes to flash on the net core to include the base address.

Interesting that FLASH_AREA_OFFSET(storage) returns the correct offset address (0x0003a00) from devicetree_unfixed.h since a BUILD_ASSERT( FLASH_AREA_OFFSET(storage) == 0x0003a00) on the net core does not fail compilation.

However when the value is printed to the console, 0x0103a00 is returned so something else under the hood is happening to give the absolute address rather than a relative address, perhaps a linker config issue.