In your board definition (board.hints) you need to define a kind of partition table. Here you give ranges in flash memory predefined names.
ZRouter expects to find these geom_map names:
|bootloader||Not mandatory, but good to know where it is. In most cases you find it at 0x00000000|
|kernel||start address could be where bootloader ends, end address can be detected automatically if you define a searchkey|
|rootfs||start address could be where kernel ends, so you can usually use the same searchkey as before|
|config||size depends on flash size, e.g. 0x00200000 bytes (2MB)|
|upgrade||use start from 'kernel' and end from 'rootfs', so these partitions are covered at once|
This geom_maps have to be defined by every board itself, because the boards use different areas in flash to store bootloader and data for wireless initialization.
TODO: example, geom_map manpage