Booting application from custom bootloader

RE: Booting application from custom bootloader

Vidar Berg — Thu, 28 Nov 2019 11:23:48 GMT

Excellent! Thanks for the update.

RE: Booting application from custom bootloader

AntonHellbe — Thu, 28 Nov 2019 10:43:47 GMT

I tested it out and it works good, cheers for all the help Vidar.

/ Anton

RE: Booting application from custom bootloader

Vidar Berg — Mon, 25 Nov 2019 08:34:02 GMT

Hi,

Yes that's correct, CODE_SIZE gives the application size and is used to locate the CRC, which is appended at the end.

RE: Booting application from custom bootloader

AntonHellbe — Fri, 22 Nov 2019 14:04:12 GMT

Hi,

Not sure if I understand the code correctly, but does the CODE_SIZE define keep track of the length/size of the application? So that you know where the CRC is located in the memory.

/ Anton

RE: Booting application from custom bootloader

AntonHellbe — Fri, 22 Nov 2019 13:05:10 GMT

I hit a fault handler when I tried to uninit fsstorage, resolved by waiting until it was not busy anymore. Now the app boots instantly :).

RE: Booting application from custom bootloader

AntonHellbe — Fri, 22 Nov 2019 07:16:06 GMT

I've been trying to find out what's going on but it seems like it might hit a fault handler?

After receiving and image, verifying its CRC and writing it to memory the nRF52832 goes unresponsive for about 30-45 seconds. When I try to read the registers nrfjprog only returns:

ERROR: JLinkARM DLL reported an error. Try again. If error condition
ERROR: persists, run the same command again with argument --log, contact Nordic
ERROR: Semiconductor and provide the generated log.log file to them.

After 30 seconds or so I can read the registers

R0:   0x01000001
R1:   0x40020518
R2:   0xE000E100
R3:   0x20002585
R4:   0x200000C0
R5:   0x00000000
R6:   0xE000E000
R7:   0x00000000
R8:   0x00000000
R9:   0x00000000
R10: 0x20000000
R11: 0x00000000
R12: 0x00000000
SP:   0x2000FF38
LR:   0x00015CCD
PC:   0x00015CCE
xPSR: 0x61000000
MSP: 0x2000FF38
PSP: 0x00000000

And the application is running.

Edit: Seems like it can take up to a minute or two. During this period I cannot connect to the nRF52832 using JLinkExe and I get disconnected when I boot the image:

****** Error: Communication timed out: Requested 12 bytes, received 0 bytes !

RE: Booting application from custom bootloader

Vidar Berg — Thu, 21 Nov 2019 09:57:27 GMT

Do you know what the device is doing when it doesn't boot the app? Maybe it went back to DFU mode inside the bootloader, or got stuck in a fault handler? You can run "nrfjprog --readregs" to find out where the program is running at.

RE: Booting application from custom bootloader

AntonHellbe — Wed, 20 Nov 2019 14:05:43 GMT

That's a nifty solution, something I will most likely use.

One thing I've noticed is that in order to boot the application (after a succesful image transfer) I always have to reset an additional time on the devkit before the application boots. It seems like the NVIC_Systemreset() is not doing the trick after the image is flashed.

Any thoughts what could be the cause?

RE: Booting application from custom bootloader

Vidar Berg — Tue, 19 Nov 2019 12:52:02 GMT

I don't think you have to have to include a settings page. An alternative is to always calculate the app CRC on boot. If the check fails, you can just let the bootloader fall back to DFU mode.

I guess the question is then where it's best to store the CRC. I encountered a fairly similar project in a project where I was trying to add DFU support without having a dedicated bootloader. I ended up appending a 32 bit CRC at the end of the app image to avoid having to allocate a settings page in flash.

devzone.nordicsemi.com/.../ble_5F00_app_5F00_beacon_5F00_w_5F00_dfu.zip

RE: Booting application from custom bootloader

AntonHellbe — Tue, 19 Nov 2019 12:30:29 GMT

Hei hei Vidar,

No I have not implemented a bootloader settings page, so yes, if there is an unexpected power loss during the transmission the bootloader would attempt to boot that application.

Are there any information create/use the settings page for "custom" behaviour?

RE: Booting application from custom bootloader

Vidar Berg — Tue, 19 Nov 2019 09:53:57 GMT

Hei Anton,

[quote user="AntonHellbe"]Is that a sufficient solution? - Clearing the GPREGRET reg and performing a NVIC_Systemreset() when booting up a new image written to flash. Or is there something else that I should to before booting up the new Image?[/quote]

Can the bootloader boot an app that has not been fully updated if the GREPREGRET flag is cleared due to an unexpected power loss,etc, or do you also have a "bootloader settings" page in flash like the SDK bootloader has?

RE: Booting application from custom bootloader

AntonHellbe — Tue, 19 Nov 2019 09:08:34 GMT

Hi,

I found the issue, after reading some of the memory addresses starting at 0x26000 I could see that the data written to flash was not correct. After correcting the memory writes the Softdevice now boots the application correctly.

Regarding booting the application after a successful image transfer. Currently I receive the image, write it to flash. When the entire Image received I calculate CRC from what's written to the memory and compare it to the CRC I receive in the start of the image transfer. If the CRC is correct, I clear the gpregret and and perform a NVIC_Systemreset() so that the bootloader will boot the new image.

Is that a sufficient solution? - Clearing the GPREGRET reg and performing a NVIC_Systemreset() when booting up a new image written to flash. Or is there something else that I should to before booting up the new Image?

Br,
Anton

RE: Booting application from custom bootloader

Vidar Berg — Tue, 19 Nov 2019 08:10:24 GMT

0x1000 is the correct address. Have you confirmed that the program reaches the jump_to_addr routine?

[quote userid="73389" url="~/f/nordic-q-a/54438/booting-application-from-custom-bootloader"]Edit: An additional question, is it possible to flash the nRF52832 using a Motorola Srecord hex file? I've tried looking for any documentation of which .hex files that nrfjprog accepts but cannot find any.[/quote]

nrfjprog supports intelHex only, but Jlink commander seems to support it.

RE: Booting application from custom bootloader

HuanVH — Fri, 15 Nov 2019 09:13:34 GMT

You can see in this post

If you using softdevice, you must start at softdevice address: 0x1000