[nrf fromlist] zephyr: Add multi-image DFU for Thingy:53

Upstream PR:
mcu-tools/mcuboot#1136

Change enables multi-image DFU in Thingy:53 configuration.
The network core cannot access external flash directly. The flash
simulator must be used to provide a memory region that is used to
forward the new firmware to the network core.

Jira: NCSDK-10750

(cherry-picked from commit d9a9983d47a27874b94f17a04dafb696b4f0f564)
Signed-off-by: Marek Pieta <[email protected]>

Author: MarekPieta

boot/zephyr/boards/thingy53_nrf5340_cpuapp.conf

@@ -7,15 +7,14 @@ CONFIG_PM=n
 CONFIG_MAIN_STACK_SIZE=10240
 CONFIG_MBEDTLS_CFG_FILE="mcuboot-mbedtls-cfg.h"
 
-CONFIG_BOOT_UPGRADE_ONLY=y
 CONFIG_BOOT_MAX_IMG_SECTORS=2048
 CONFIG_BOOT_SIGNATURE_TYPE_RSA=y
 
 # Flash
 CONFIG_FLASH=y
 CONFIG_BOOT_ERASE_PROGRESSIVELY=y
 CONFIG_SOC_FLASH_NRF_EMULATE_ONE_BYTE_WRITE_ACCESS=y
-CONFIG_FPROTECT=n
+CONFIG_FPROTECT=y
 
 # Serial
 CONFIG_SERIAL=y
@@ -24,6 +23,7 @@ CONFIG_UART_LINE_CTRL=y
 # MCUBoot serial
 CONFIG_GPIO=y
 CONFIG_MCUBOOT_SERIAL=y
+CONFIG_MCUBOOT_SERIAL_DIRECT_IMAGE_UPLOAD=y
 CONFIG_BOOT_SERIAL_CDC_ACM=y
 CONFIG_BOOT_SERIAL_DETECT_PORT="GPIO_1"
 CONFIG_BOOT_SERIAL_DETECT_PIN=13
@@ -33,6 +33,7 @@ CONFIG_NORDIC_QSPI_NOR=y
 CONFIG_NORDIC_QSPI_NOR_FLASH_LAYOUT_PAGE_SIZE=4096
 CONFIG_NORDIC_QSPI_NOR_STACK_WRITE_BUFFER_SIZE=16
 
+CONFIG_PM_EXTERNAL_FLASH_SUPPORT_LEGACY=y
 CONFIG_PM_EXTERNAL_FLASH=y
 CONFIG_PM_EXTERNAL_FLASH_DEV_NAME="MX25R64"
 CONFIG_PM_EXTERNAL_FLASH_BASE=0x0
@@ -64,3 +65,13 @@ CONFIG_RESET_ON_FATAL_ERROR=n
 CONFIG_SPI=n
 CONFIG_I2C=n
 CONFIG_UART_NRFX=n
+
+# The following configurations are required to support simultaneous multi image update
+CONFIG_PCD_APP=y
+CONFIG_UPDATEABLE_IMAGE_NUMBER=2
+CONFIG_BOOT_UPGRADE_ONLY=y
+# The network core cannot access external flash directly. The flash simulator must be used to
+# provide a memory region that is used to forward the new firmware to the network core.
+CONFIG_FLASH_SIMULATOR=y
+CONFIG_FLASH_SIMULATOR_DOUBLE_WRITES=y
+CONFIG_FLASH_SIMULATOR_STATS=n