Kconfig.tfm: Add TFM_MCUBOOT_IMAGE_NUMBER config

Controlling the number of images in TFM's BL2/mcuboot.

Signed-off-by: Øyvind Rønningstad <oyvind.ronningstad@nordicsemi.no>

modules/trusted-firmware-m/CMakeLists.txt

@@ -31,7 +31,8 @@
 #                        BUILD_PROFILE profile_small)
 function(trusted_firmware_build)
   set(options IPC REGRESSION)
-  set(oneValueArgs BINARY_DIR BOARD BL2 ISOLATION_LEVEL CMAKE_BUILD_TYPE BUILD_PROFILE)
+  set(oneValueArgs BINARY_DIR BOARD BL2 ISOLATION_LEVEL CMAKE_BUILD_TYPE BUILD_PROFILE
+    MCUBOOT_IMAGE_NUMBER)
   cmake_parse_arguments(TFM "${options}" "${oneValueArgs}" "" ${ARGN})
 
   if(NOT DEFINED TFM_BL2)
@@ -63,6 +64,9 @@ function(trusted_firmware_build)
     set(TFM_PROFILE_ARG -DTFM_PROFILE=${TFM_BUILD_PROFILE})
   endif()
 
+  if(DEFINED TFM_MCUBOOT_IMAGE_NUMBER)
+    set(MCUBOOT_IMAGE_NUM_ARG -DMCUBOOT_IMAGE_NUMBER=${TFM_MCUBOOT_IMAGE_NUMBER})
+  endif()
 
   set(VENEERS_FILE ${TFM_BINARY_DIR}/secure_fw/s_veneers.o)
   set(PSA_API_NS_PATH ${TFM_BINARY_DIR}/interface/libpsa_api_ns.a)
@@ -125,6 +129,7 @@ function(trusted_firmware_build)
                ${TFM_ISOLATION_LEVEL_ARG}
                ${TFM_REGRESSION_ARG}
                ${TFM_PROFILE_ARG}
+               ${MCUBOOT_IMAGE_NUM_ARG}
                -DTFM_TEST_REPO_PATH=${ZEPHYR_TRUSTED_FIRMWARE_M_MODULE_DIR}/tf-m-tests
                -DMCUBOOT_PATH=${ZEPHYR_TRUSTED_FIRMWARE_M_MODULE_DIR}/../tfm-mcuboot
     BUILD_ALWAYS True
@@ -207,12 +212,17 @@ if (CONFIG_BUILD_WITH_TFM)
   elseif (CONFIG_TFM_CMAKE_BUILD_TYPE_RELWITHDEBINFO)
     set(TFM_CMAKE_BUILD_TYPE "RelWithDebInfo")
   endif()
+  if (DEFINED CONFIG_TFM_MCUBOOT_IMAGE_NUMBER)
+    set(TFM_IMAGE_NUMBER_ARG
+        MCUBOOT_IMAGE_NUMBER ${CONFIG_TFM_MCUBOOT_IMAGE_NUMBER})
+  endif()
 
   trusted_firmware_build(
     BINARY_DIR ${CMAKE_BINARY_DIR}/tfm
     BOARD ${CONFIG_TFM_BOARD}
     ${TFM_ISOLATION_LEVEL_ARG}
     ${TFM_PROFILE_ARG}
+    ${TFM_IMAGE_NUMBER_ARG}
     ${TFM_BL2_ARG}
     ${TFM_IPC_ARG}
     ${TFM_REGRESSION_ARG}

modules/trusted-firmware-m/Kconfig

@@ -116,6 +116,16 @@ config TFM_BL2_FALSE
 
 endchoice
 
+config TFM_MCUBOOT_IMAGE_NUMBER
+	int "Granularity of FW updates of TFM and app"
+	range 1 2
+	default 2
+	help
+	  How many images the bootloader sees when it looks at TFM and the app.
+	  When this is 1, the S and NS are considered as 1 image and must be
+	  updated in one atomic operation. When this is 2, they are split and
+	  can be updated independently if dependency requirements are met.
+
 config TFM_IPC
 	bool "IPC"
 	help