Secure bootloader doesn't start

[Anton K.]

Hi all. I try to implement ble dfu bootloader project via getting start from  SDK/examples/dfu/secure_bootloader/pca10056_ble_debug project. 

Using:

OS: Linux

Compiler: armgcc (toolchain gcc-arm-none-eabi-7-2018-q2-update), eclipse

Softdevice: s140_nrf52_6.1.1_softdevice

SDK: nRF5_SDK_15.3.0_59ac345

Hard: PCA10056 DK

I just successfully compile exist project and flash softdevice, then bootloader. I can't see any DfuTaarg on nRF Connect Mobile app. I haven't any errors messages, any warnings.
After flashing precompiled .hex to board. If seems work with BLE advertising of DfuTarg. What should I do?
Thanks for attention.

[Anton K.]

Resolved. nRF5_SDK_15.3.0_59ac345/examples/dfu/secure_bootloader/pca10056_ble/armgcc/secure_bootloader_gcc_nrf52.ld has bootloader start address and mbr params page addressed on Softdevice memory????

uicr_bootloader_start_address (r) : ORIGIN = 0x00000FF8, LENGTH = 0x4

...

  uicr_mbr_params_page (r) : ORIGIN = 0x00000FFC, LENGTH = 0x4

I change it like it was on oldest SDK (some project with bootloader I had) by this way, and got success:

/*  uicr_bootloader_start_address (r) : ORIGIN = 0x00000FF8, LENGTH = 0x4 */
  uicr_bootloader_start_address (r) : ORIGIN = 0x10001014, LENGTH = 0x4
/*  uicr_mbr_params_page (r) : ORIGIN = 0x00000FFC, LENGTH = 0x4 */
  uicr_mbr_params_page (r) : ORIGIN = 0x10001018, LENGTH = 0x4

[Vidar Berg]

Hi,

In SDK 15.3.0, we started to use the MBR section to hold the bootloader start address and MBR param page address. The background for this change was that it's not possible to enable memory protection (BPROT/ACL) on the UICR section. Please see this answer from Sigurd for more details: https://devzone.nordicsemi.com/f/nordic-q-a/44872/bootloader-does-not-work-if-compiled-using-armgcc/176446#176446 

[Anton K.]

Thank you for your explanation