Issues with nrf_bootloader_app_start and the SDK 16.0.0

RE: Issues with nrf_bootloader_app_start and the SDK 16.0.0

rsoc16 — Fri, 28 Aug 2020 13:46:28 GMT

Einar, thank you for the clarification. So I should be following the process laid out in SDK 14.2. I went ahead and implemented that, and the jump to application seems to be working like a charm.

I am having faults on execution of the application after bootloader init, but this is most likely due to initialization carrying over between applications I assume...time for the next challenge!

RE: Issues with nrf_bootloader_app_start and the SDK 16.0.0

Einar Thorsrud — Fri, 28 Aug 2020 13:04:50 GMT

Hi,

I am sorry, there was a mistake in the text. I meant to say "This is what you should do when the application is not always immediately after the MBR" (not bootloader). But the rest of the post is correct, and the key is that you need to use the approach you see in nrf_bootloader_app_start.c from SDK 14.2. In other words, you can not use SD_MBR_COMMAND_IRQ_FORWARD_ADDRESS_SET in your case, but instead, you should use SD_MBR_COMMAND_INIT_SD and SD_MBR_COMMAND_VECTOR_TABLE_BASE_SET.

RE: Issues with nrf_bootloader_app_start and the SDK 16.0.0

rsoc16 — Fri, 28 Aug 2020 12:53:16 GMT

Einar, thank you for the quick response. A follow up:

You said

[quote userid="7377" url="~/f/nordic-q-a/65346/issues-with-nrf_bootloader_app_start-and-the-sdk-16-0-0/266998"]This is what you should do when the application is not always immediately after the bootloader.[/quote]

So if my memory is set up to be:

Top of flash

Bootloader 0x70000 - 0x7E000

Application 0x19000 - 0x70000

Soft Device 0x1000 - 0x19000

MBR 0x0000 - 0x1000

Bottom of flash: 0x0000000

Then this means my application is not immediately after the bootloader, andI should be following that approach? Is that what you mean? I ask because I am following the approach using SD_MBR_COMMAND_IRQ_FORWARD_ADDRESS_SET (nrf_dfu_mbr_irq_forward_address_set()) currently, with no avail.

RE: Issues with nrf_bootloader_app_start and the SDK 16.0.0

Einar Thorsrud — Fri, 28 Aug 2020 12:19:10 GMT

Hi,

You need to use a different MBR command in order to jump to another address than 0x1000. Specifically, In SDK >= 15.0.0, the boot process consists of forwarding interrupts to the SoftDevice using SD_MBR_COMMAND_IRQ_FORWARD_ADDRESS_SET (nrf_dfu_mbr_irq_forward_address_set()), and then always jumping to address 0x1000 (SoftDevice start) instead of the application start address.

Another approach, which was used up to and including SDK 14.2 was to use the SD_MBR_COMMAND_INIT_SD and SD_MBR_COMMAND_VECTOR_TABLE_BASE_SET command and start the application at a specific address. This is what you should do when the application is not always immediately after the MBR.

You can compare components\libraries\bootloader\nrf_bootloader_app_start.c in SDK 14.2 and a newer SDK to see both approaches.

Update: Fixed mistake referring to bootloader instead of MBR at the end of the second paragraph.

Br,

Einar