trusted-firmware-m: Set --max-sectors when signing

The --max-sectors will helps to catch problems with flash overlap when
merging images. If there is a missalignment from flash partitions
usually the merge process will fail. This pick information from zephyr
flash partitions and flash controller to automatically determine the
max sectors value and apply it when singing an image.

Signed-off-by: BUDKE Gerson Fernando <[email protected]>

Author: nandojve

modules/trusted-firmware-m/CMakeLists.txt

@@ -446,6 +446,7 @@ if (CONFIG_BUILD_WITH_TFM)
 
   dt_chosen(chosen_flash PROPERTY "zephyr,flash")
   dt_prop(flash_write_block_size PATH ${chosen_flash} PROPERTY write-block-size)
+  dt_prop(flash_erase_block_size PATH ${chosen_flash} PROPERTY erase-block-size)
   # The alignment is determined by the minimal amount of bytes necessary to
   # be written in the flash sector. Ex., assuming that the sector erase
   # operation is 1KiB and, on that sector, the minimal amount of bytes that
@@ -463,8 +464,15 @@ if (CONFIG_BUILD_WITH_TFM)
   else()
     set(image_alignment 1)
   endif()
+  # Calculate the maximum number of sectors necessary to store the image.
+  dt_nodelabel(s_partition_node NODELABEL "slot0_partition")
+  dt_nodelabel(ns_partition_node NODELABEL "slot0_ns_partition")
+  dt_reg_size(s_partition_size PATH ${s_partition_node})
+  dt_reg_size(ns_partition_size PATH ${ns_partition_node})
+  math(EXPR S_MAX_SECTORS "${s_partition_size} / ${flash_erase_block_size}")
+  math(EXPR NS_MAX_SECTORS "${ns_partition_size} / ${flash_erase_block_size}")
 
-  function(tfm_sign OUT_ARG SUFFIX PAD INPUT_FILE OUTPUT_FILE)
+  function(tfm_sign OUT_ARG SUFFIX PAD MAX_SECTORS INPUT_FILE OUTPUT_FILE)
     if(PAD)
       set(pad_args --pad --pad-header)
     endif()
@@ -484,6 +492,7 @@ if (CONFIG_BUILD_WITH_TFM)
       -k ${CONFIG_TFM_KEY_FILE_${SUFFIX}}
       --public-key-format ${TFM_PUBLIC_KEY_FORMAT}
       --align ${image_alignment}
+      --max-sectors ${MAX_SECTORS}
       -v ${CONFIG_TFM_IMAGE_VERSION_${SUFFIX}}
       ${pad_args}
       ${HEX_ADDR_ARGS_${SUFFIX}}
@@ -524,7 +533,7 @@ if (CONFIG_BUILD_WITH_TFM)
     )
 
   elseif(CONFIG_TFM_MCUBOOT_IMAGE_NUMBER STREQUAL "1")
-    tfm_sign(sign_cmd S_NS TRUE ${S_NS_FILE} ${S_NS_SIGNED_FILE})
+    tfm_sign(sign_cmd S_NS TRUE ${S_MAX_SECTORS} ${S_NS_FILE} ${S_NS_SIGNED_FILE})
 
     set_property(GLOBAL APPEND PROPERTY extra_post_build_commands
       COMMAND ${PYTHON_EXECUTABLE} ${ZEPHYR_BASE}/scripts/build/mergehex.py
@@ -549,12 +558,12 @@ if (CONFIG_BUILD_WITH_TFM)
 
   else()
     if (CONFIG_TFM_USE_NS_APP)
-      tfm_sign(sign_cmd_ns NS TRUE ${NS_APP_FILE} ${NS_SIGNED_FILE})
+      tfm_sign(sign_cmd_ns NS TRUE ${NS_MAX_SECTORS} ${NS_APP_FILE} ${NS_SIGNED_FILE})
     else()
-      tfm_sign(sign_cmd_ns NS FALSE ${NS_APP_FILE} ${NS_SIGNED_FILE})
+      tfm_sign(sign_cmd_ns NS FALSE ${NS_MAX_SECTORS} ${NS_APP_FILE} ${NS_SIGNED_FILE})
     endif()
 
-    tfm_sign(sign_cmd_s S TRUE $<TARGET_PROPERTY:tfm,TFM_S_HEX_FILE> ${S_SIGNED_FILE})
+    tfm_sign(sign_cmd_s S TRUE ${S_MAX_SECTORS} $<TARGET_PROPERTY:tfm,TFM_S_HEX_FILE> ${S_SIGNED_FILE})
 
     #Create and sign for concatenated binary image, should align with the TF-M BL2
     set_property(GLOBAL APPEND PROPERTY extra_post_build_commands