Speed up start up after leaving system off

RE: Speed up start up after leaving system off

Marelcom — Mon, 20 Jan 2025 09:27:42 GMT

Finaly this case could be solved. Here is the summary:

Nordic: I described the approach for sysbuild, but you are using the old child-parent image (which I should have assumed when you wrote you use SDK 2.6. So there is a slight difference. You should add the same config (CONFIG_BOOT_VALIDATE_SLOT0=n), but the folder name where you place mcuboot.conf must be "child_image" and not "sysbuild".

Markus: After adding mcuboot.conf file to the child_image folder (see screenshot) and CONFIG_BOOT_VALIDATE_SLOT0=n then it works.
In the file "mcuboot/zephyr/.config" CONFIG_BOOT_VALIDATE_SLOT0 is not added any more (see screenshot). Start up time is now decreased by 400ms around.

Nordic: A second factor that could add 200-400 us to the startup time is if you have an external 32.768 kHz crystall, as this takes a significant amount of time to start (depending on the crystal). If so, you can disable the LFXO and use LFRC intead by setting CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC=y (remembed to change in the board files, or alternatively both in the bootloader and application configuration, so that there is no conflict).

Markus: while changing CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC=y then the start time is shortened again by almost 400ms. Current start up time is about 50ms. That's fast enough and I can move on.

thanks a lot for your very helpful support
bes regards
Markus

RE: Speed up start up after leaving system off

Einar Thorsrud — Thu, 09 Jan 2025 14:31:16 GMT

Hi,

If you add a mcuboot.conf in a folder called sysbuild directly in the project folder (where you have prj.conf and CMakeLists.txt etc), this will be picked up automatically. For instance, you can take the smp_svr sample and add a file called mcuboot.conf under sysbuild and add a line with CONFIG_BOOT_VALIDATE_SLOT0=n, and you will see that the generated .config no longer has CONFIG_BOOT_VALIDATE_SLOT0 set. I verified this approach on my end.

If you can't make it work, can you share the project with your modification so that I can see?

RE: Speed up start up after leaving system off

Marelcom — Thu, 09 Jan 2025 10:22:25 GMT

Thanks.

You are right in the build folder mcuboot/zephyr/.config is CONFIG_BOOT_VALIDATE_SLOT0 set to y.
I added the suggestes mcboot.conf file to the sysbuild folder. Do I have to add the mcuboot.conf file to the build configuration? I yes where? I did add it to "Base configuration files" but then build still does not run without error

c:/SwProjects/Laufkarte/trunk/Laufkarte/sysbuild/mcuboot.conf:1: warning: attempt to assign the value 'n' to the undefined symbol BOOT_VALIDATE_SLOT0

error: Aborting due to Kconfig warnings

CMake Error at C:/ncs/v2.6.1/zephyr/cmake/modules/kconfig.cmake:358 (message):
  command failed with return code: 1
Call Stack (most recent call first):
  C:/ncs/v2.6.1/nrf/cmake/modules/kconfig.cmake:29 (include)
  C:/ncs/v2.6.1/zephyr/cmake/modules/zephyr_default.cmake:129 (include)
  C:/ncs/v2.6.1/zephyr/share/zephyr-package/cmake/ZephyrConfig.cmake:66 (include)
  C:/ncs/v2.6.1/zephyr/share/zephyr-package/cmake/ZephyrConfig.cmake:92 (include_boilerplate)
  CMakeLists.txt:9 (find_package)


-- Configuring incomplete, errors occurred!
FATAL ERROR: command exited with status 1: 'C:\ncs\toolchains\cf2149caf2\opt\bin\cmake.EXE' -DWEST_PYTHON=C:/ncs/toolchains/cf2149caf2/opt/bin/python.exe '-Bc:\SwProjects\Laufkarte\trunk\Laufkarte\build_release' -GNinja -DBOARD=laufkarte_nrf52832 -DNCS_TOOLCHAIN_VERSION=NONE '-DCONF_FILE=c:/SwProjects/Laufkarte/trunk/Laufkarte/prj_release.conf;c:/SwProjects/Laufkarte/trunk/Laufkarte/sysbuild/mcuboot.conf' -DBOARD_ROOT=c:/swprojects/laufkarte/trunk/laufkarte '-Sc:\SwProjects\Laufkarte\trunk\Laufkarte'

RE: Speed up start up after leaving system off

Einar Thorsrud — Thu, 09 Jan 2025 09:20:43 GMT

Hi Markus,

CONFIG_BOOT_VALIDATE_SLOT0 is part of the MCUboot configuration. If you check the build folder for your project, you can refer to see mcuboot/zephyr/.config and there I expect you will set CONFIG_BOOT_VALIDATE_SLOT0 is set to y, as that is the default. This shows the configs that are used for the project. You need to set it to n for mcuboot, so that could be either in the mcuboot prj.conf, or in an overlay file. The cleanest is probably to make a mcuboot.conf in a folder called sysbuild in your application folder, in the same way as here, and add the config there. After a re-build, you can check the .config I refered to to verify that it is being used.

RE: Speed up start up after leaving system off

Marelcom — Thu, 09 Jan 2025 08:47:43 GMT

thanks for your Answer.

CONFIG_BOOT_VALIDATE_SLOT0=n does not work. I got the compiler error, BOOT_VALIDATE_SLOT0 is undefined: What else do I have to add to the prj.conf file?

#
# Copyright (c) 2019 Nordic Semiconductor ASA
#
# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
#
CONFIG_NCS_SAMPLES_DEFAULTS=y

CONFIG_DK_LIBRARY=y

#CONFIG_NFC_T2T_NRFXLIB=y  # NFC library only for read
CONFIG_NFC_T4T_NRFXLIB=y   # NFC library for read and write

CONFIG_NFC_NDEF=y
CONFIG_NFC_NDEF_MSG=y
CONFIG_NFC_NDEF_RECORD=y
CONFIG_NFC_NDEF_TEXT_RECORD=y
CONFIG_NFC_NDEF_URI_REC=y
CONFIG_NFC_NDEF_URI_MSG=y

CONFIG_MPU_ALLOW_FLASH_WRITE=y
CONFIG_FLASH=y
CONFIG_FLASH_PAGE_LAYOUT=y
CONFIG_NVS=y

CONFIG_SPI=y

CONFIG_CRC=y
CONFIG_APP_RETENTION=y  # used to keep data in RAM during stystem off

#power save
CONFIG_POWEROFF=y
CONFIG_PM_DEVICE=y

CONFIG_SERIAL=n
CONFIG_CONSOLE=n
CONFIG_UART_CONSOLE=n
CONFIG_LOG=n 


# Enable Bluetooth for FOTA (DFU)
CONFIG_BT=y
CONFIG_BT_PERIPHERAL=y
CONFIG_BT_DEVICE_NAME="Laufkarte"
# Enable MCUboot and FOTA
CONFIG_BOOTLOADER_MCUBOOT=y
CONFIG_NCS_SAMPLE_MCUMGR_BT_OTA_DFU=y
CONFIG_BOOT_VALIDATE_SLOT0=n

# enable GPIO
CONFIG_GPIO=y

#save startup time
CONFIG_BOOT_BANNER=n
CONFIG_PRINTK=n
CONFIG_DEBUG=n
CONFIG_INIT_STACKS=n
CONFIG_SHELL=n


#set main thread priority
CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC=y

thanks
Markus

RE: Speed up start up after leaving system off

Einar Thorsrud — Tue, 07 Jan 2025 13:46:16 GMT

Hi Markus,

I suspect that the main contributer to the increased startup time is from the bootloader validating the application image. You can disable that using CONFIG_BOOT_VALIDATE_SLOT0=n. If you do, the image will only be validated during DFU, but not for subsequent boots. Please note that this means that if for any reason the application region is corrupted or manipulated, the bootloader will boot it non the less, which you should be aware of from a security perspective.