Adding USB capability to secure DFU BLE bootloader

Thanks for the response. I was able to modify the FLASH regions in the linker script in the following manner to eliminate the overflow by 284 bytes and the overlap in the sections, but still get the following error (which is not too descriptive):

"region FLASH overflowed with .data and user data"

/* Linker script to configure memory regions. */

SEARCH_DIR(.)
GROUP(-lgcc -lc -lnosys)

MEMORY
{
FLASH (rx) : ORIGIN = 0xf3ed8, LENGTH = 0xa128
RAM (rwx) : ORIGIN = 0x20000008, LENGTH = 0x3fff8
uicr_bootloader_start_address (r) : ORIGIN = 0x10001014, LENGTH = 0x4
bootloader_settings_page (r) : ORIGIN = 0x000FF000, LENGTH = 0x1000
uicr_mbr_params_page (r) : ORIGIN = 0x10001018, LENGTH = 0x4
mbr_params_page (r) : ORIGIN = 0x000FE000, LENGTH = 0x1000
}

SECTIONS
{
. = ALIGN(4);
.uicr_bootloader_start_address :
{
PROVIDE(__start_uicr_bootloader_start_address = .);
KEEP(*(SORT(.uicr_bootloader_start_address*)))
PROVIDE(__stop_uicr_bootloader_start_address = .);
} > uicr_bootloader_start_address
. = ALIGN(4);
.bootloader_settings_page(NOLOAD) :
{
PROVIDE(__start_bootloader_settings_page = .);
KEEP(*(SORT(.bootloader_settings_page*)))
PROVIDE(__stop_bootloader_settings_page = .);
} > bootloader_settings_page
. = ALIGN(4);
.uicr_mbr_params_page :
{
PROVIDE(__start_uicr_mbr_params_page = .);
KEEP(*(SORT(.uicr_mbr_params_page*)))
PROVIDE(__stop_uicr_mbr_params_page = .);
} > uicr_mbr_params_page
. = ALIGN(4);
.mbr_params_page(NOLOAD) :
{
PROVIDE(__start_mbr_params_page = .);
KEEP(*(SORT(.mbr_params_page*)))
PROVIDE(__stop_mbr_params_page = .);
} > mbr_params_page
}

SECTIONS
{
. = ALIGN(4);
.mem_section_dummy_ram :
{
}
.fs_data :
{
PROVIDE(__start_fs_data = .);
KEEP(*(.fs_data))
PROVIDE(__stop_fs_data = .);
} > RAM
.log_dynamic_data :
{
PROVIDE(__start_log_dynamic_data = .);
KEEP(*(SORT(.log_dynamic_data*)))
PROVIDE(__stop_log_dynamic_data = .);
} > RAM
.log_filter_data :
{
PROVIDE(__start_log_filter_data = .);
KEEP(*(SORT(.log_filter_data*)))
PROVIDE(__stop_log_filter_data = .);
} > RAM

} INSERT AFTER .data;

SECTIONS
{
.mem_section_dummy_rom :
{
}
.crypto_data :
{
PROVIDE(__start_crypto_data = .);
KEEP(*(SORT(.crypto_data*)))
PROVIDE(__stop_crypto_data = .);
} > FLASH
.dfu_trans :
{
PROVIDE(__start_dfu_trans = .);
KEEP(*(SORT(.dfu_trans*)))
PROVIDE(__stop_dfu_trans = .);
} > FLASH
.svc_data :
{
PROVIDE(__start_svc_data = .);
KEEP(*(.svc_data))
PROVIDE(__stop_svc_data = .);
} > FLASH
.nrf_queue :
{
PROVIDE(__start_nrf_queue = .);
KEEP(*(.nrf_queue))
PROVIDE(__stop_nrf_queue = .);
} > FLASH
.log_const_data :
{
PROVIDE(__start_log_const_data = .);
KEEP(*(SORT(.log_const_data*)))
PROVIDE(__stop_log_const_data = .);
} > FLASH
.nrf_balloc :
{
PROVIDE(__start_nrf_balloc = .);
KEEP(*(.nrf_balloc))
PROVIDE(__stop_nrf_balloc = .);
} > FLASH
.sdh_ble_observers :
{
PROVIDE(__start_sdh_ble_observers = .);
KEEP(*(SORT(.sdh_ble_observers*)))
PROVIDE(__stop_sdh_ble_observers = .);
} > FLASH
.log_backends :
{
PROVIDE(__start_log_backends = .);
KEEP(*(SORT(.log_backends*)))
PROVIDE(__stop_log_backends = .);
} > FLASH
.sdh_req_observers :
{
PROVIDE(__start_sdh_req_observers = .);
KEEP(*(SORT(.sdh_req_observers*)))
PROVIDE(__stop_sdh_req_observers = .);
} > FLASH
.sdh_state_observers :
{
PROVIDE(__start_sdh_state_observers = .);
KEEP(*(SORT(.sdh_state_observers*)))
PROVIDE(__stop_sdh_state_observers = .);
} > FLASH
.sdh_stack_observers :
{
PROVIDE(__start_sdh_stack_observers = .);
KEEP(*(SORT(.sdh_stack_observers*)))
PROVIDE(__stop_sdh_stack_observers = .);
} > FLASH
.sdh_soc_observers :
{
PROVIDE(__start_sdh_soc_observers = .);
KEEP(*(SORT(.sdh_soc_observers*)))
PROVIDE(__stop_sdh_soc_observers = .);
} > FLASH

} INSERT AFTER .text

INCLUDE "nrf_common.ld"

It looks like you still need to move the bootloader start address down a bit (say 0x2000 down). See this thread.

Thanks for the response.

• By the bootloader start address, do you mean the "uicr_bootloader_start_address"?
• How did you determine that it's the bootloader that needs to be moved down (since the error isn't descriptive)?
• By "down", do you mean to increase the value of the origin? 

Hi,

mablabs said:

By the bootloader start address, do you mean the "uicr_bootloader_start_address"?

No. That is the address where the bootloader start address is placed, and that happens automatically during the build. I mean the start address of the bootloader, which is what you set in your linker configuration, in the exact same way as you set the start address of your application. Specifically, in this line FLASH ORIGIN is where you set the start address:

  FLASH (rx) : ORIGIN =...

I did not spot this before, but you also have this set to a odd value. note that this must always be page aligned (so it must be a multiple of 0x1000).

mablabs said:

How did you determine that it's the bootloader that needs to be moved down (since the error isn't descriptive)?

That may have been a wrong assumption, I was thinking that you were building the bootloader project? If you are, then that is what needs to move, as the message tells you that it cannot fit whatever you are building in the flash region you have specified in the linker script.

mablabs said:

By "down", do you mean to increase the value of the origin? 

No, I mean decrease the value. With a lower start address you can increase the size (the end address is given by the physically available flash memory). Note that you must ensure that you do not move it so far down that it overlaps with your application and also leave room for potential application data in the flash area between the application itself and the bootloader (if any)

Hi Einar,

Thanks for the response. I was able to create a bootloader that looks to support both USB and BLE. I was able to perform a DFU using USB and the application comes up. However, when I perform a DFU over BLE, I get a "GATT ERROR". Should I create another thread for that error?