FLS_OFFSET_CPYR
#define FLS_LENGTH_BOOT (FLS_OFFSET_CPYR - FLS_OFFSET_BOOT)
if (!esas2r_read_flash_block(a, bytes, FLS_OFFSET_CPYR - sz, sz))
fc->flsh_addr = FLS_OFFSET_CPYR - ch->length;
fc->flsh_addr = FLS_OFFSET_CPYR - ch->length;