Bug? Partition manager does not use device tree sizes for bootloader/settings partitions.

[anthony32086]

When compiling without a pm_static.yml in my project and using the dynamic partition resolver with mcuboot I noticed that I get an overflow error.

The current accepted fix in examples seems to be increasing CONFIG_PM_PARTITION_SIZE_MCUBOOT to the size in the device tree rather than the hardcoded value of 0xc000. However this isn't ideal since changes in device tree do not get automatically propagated.

I was able to extract the values from the device tree for both mcuboot and settings storage with the following diff.

diff --git a/modules/mcuboot/boot/zephyr/Kconfig b/modules/mcuboot/boot/zephyr/Kconfig
index ef150f0d8..674a13e5d 100644
--- a/modules/mcuboot/boot/zephyr/Kconfig
+++ b/modules/mcuboot/boot/zephyr/Kconfig
@@ -29,8 +29,10 @@ config PM_PARTITION_SIZE_MCUBOOT
        default 0x7c00
        depends on BOOT_USE_MIN_PARTITION_SIZE && !BOOT_NRF_EXTERNAL_CRYPTO
 
+DT_PARTITION_MCUBOOT_PATH := $(dt_nodelabel_path,boot_partition)
 config PM_PARTITION_SIZE_MCUBOOT
        hex "Flash space allocated for the MCUboot partition." if !BOOT_USE_MIN_PARTITION_SIZE
+       default $(dt_node_reg_size_hex,$(DT_PARTITION_MCUBOOT_PATH)) if $(dt_nodelabel_enabled,boot_partition)
        default 0xc000
        help
          Flash space set aside for the MCUboot partition.
diff --git a/subsys/partition_manager/Kconfig b/subsys/partition_manager/Kconfig
index df38d3500..bb1fcd35d 100644
--- a/subsys/partition_manager/Kconfig
+++ b/subsys/partition_manager/Kconfig
@@ -51,16 +51,22 @@ partition-size=0x6000
 rsource "Kconfig.template.partition_size"
 endif
 
+DT_PARTITION_STORAGE_PATH := $(dt_nodelabel_path,storage_partition)
+config PARTITION_SIZE_STORAGE
+       hex
+       default $(dt_node_reg_size_hex,$(DT_PARTITION_STORAGE_PATH)) if $(dt_nodelabel_enabled,storage_partition)
+       default 0x2000 if (SETTINGS_FCB || SETTINGS_NVS)
+       default 0x6000 if (NVS && !SETTINGS_NVS)
 
 if SETTINGS_FCB || SETTINGS_NVS
 partition=SETTINGS_STORAGE
-partition-size=0x2000
+partition-size=PARTITION_SIZE_STORAGE
 rsource "Kconfig.template.partition_size"
 endif
 
 if NVS && !SETTINGS_NVS
 partition=NVS_STORAGE
-partition-size=0x6000
+partition-size=PARTITION_SIZE_STORAGE
 rsource "Kconfig.template.partition_size"
 endif

[Vidar Berg]

Hi,

The DT partitions are ignored when the partition manager is enabled. This was a deliberate choice made by the developers made when they designed it. I'm not sure what the exact reasons were. My guess is that it was needed to allow the PM to automatically resolve conflicts without requiring changes to the DT files.

There is a note about this in the partition manager documentation here: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/2.0.2/nrf/scripts/partition_manager/partition_manager.html#partition-manager which could have been made more visible.

Best regards,

Vidar