cmake: linker generator: MPU_ALIGN for CONFIG_CMAKE_LINKER_GENERATOR

Make gen_app_partitions.py pass size argument to SMEM_PARTIOTION_ALIGN
Implement MPU_ALIGN for CONFIG_CMAKE_LINKER_GENERATOR for cortex-m, and
setup SMEM_PARTITION_ALIGN to use MPU_ALIGN. Following the pattern of
how it is setup in the non-generator scrips.

This is an example of how the recursive @@ variables can be used to implement MPU_ALIGN(region_size)

Signed-off-by: Björn Bergman <bjorn.bergman@iar.com>

Author: bjorniuppsala

cmake/linker_script/arm/linker.cmake

@@ -22,16 +22,15 @@ if((NOT DEFINED CONFIG_CUSTOM_SECTION_ALIGN) AND DEFINED  CONFIG_MPU_REQUIRES_PO
   # . = ALIGN( 1 << LOG2CEIL(region_size))
   # Handling this requires us to handle log2ceil() in iar linker since the size
   # isn't known until then.
-  set(MPU_ALIGN_BYTES ${region_min_align})
+  zephyr_linker_include_var(VAR MPU_ALIGN VALUE "MAX(${region_min_align} , 1 << LOG2CEIL(@region_size@) )")
   #message(WARNING "We can not handle . = ALIGN( 1 << LOG2CEIL(region_size))  ")
 else()
-  set(MPU_ALIGN_BYTES ${region_min_align})
+  zephyr_linker_include_var(VAR MPU_ALIGN VALUE "${region_min_align}")
 endif()
-# The APP_SHARED_ALIGN and SMEM_PARTITION_ALIGN macros are defined as
-# ". = ALIGN(...)" things.
-# the cmake generator stuff needs an align-size in bytes so:
-zephyr_linker_include_var(VAR APP_SHARED_ALIGN_BYTES VALUE ${region_min_align})
-zephyr_linker_include_var(VAR SMEM_PARTITION_ALIGN_BYTES VALUE ${MPU_ALIGN_BYTES})
+
+zephyr_linker_include_var(VAR APP_SHARED_ALIGN VALUE ${region_min_align})
+# Note that MPU_ALIGN (may) require an argument (region_size
+zephyr_linker_include_var(VAR SMEM_PARTITION_ALIGN VALUE "@MPU_ALIGN@")
 
 # Note, the `+ 0` in formulas below avoids errors in cases where a Kconfig
 #       variable is undefined and thus expands to nothing.

scripts/build/gen_app_partitions.py

@@ -279,8 +279,9 @@ def zephyr_linker_symbol(symbol, expr) :
 
 class CmakeTemplate:
     section_name = "@_APP_SMEM{SECTION}_SECTION_NAME@"
+    smem_partition_align = "@SMEM_PARTITION_ALIGN,region_size=z_data_smem_{partition}_bss_end - z_data_smem_{partition}_part_start@"
     data_template = (
-        zephyr_linker_section_configure(section=section_name, align="@SMEM_PARTITION_ALIGN_BYTES@")+
+        zephyr_linker_section_configure(section=section_name, align=smem_partition_align)+
         zephyr_linker_section_configure(section=section_name, input="data_smem_{partition}_data*", symbols="z_data_smem_{partition}_part_start", keep=True)
     )
 
@@ -294,20 +295,20 @@ class CmakeTemplate:
 
     footer_template = (
         zephyr_linker_section_configure(section=section_name, symbols="z_data_smem_{partition}_bss_end", keep=True) +
-        zephyr_linker_section_configure(section=section_name, align="@SMEM_PARTITION_ALIGN_BYTES@") +
+        zephyr_linker_section_configure(section=section_name, align=smem_partition_align) +
         zephyr_linker_section_configure(section=section_name, symbols="z_data_smem_{partition}_part_end", keep=True)
     )
 
     linker_start_seq = (
         zephyr_linker_section(name=section_name, group="APP_SMEM_GROUP", noinput=True, align_with_input=True) +
-        zephyr_linker_section_configure(section=section_name, align="@APP_SHARED_ALIGN_BYTES@", symbols="_app_smem{section}_start"))
+        zephyr_linker_section_configure(section=section_name, align="@APP_SHARED_ALIGN@", symbols="_app_smem{section}_start"))
 
     linker_end_seq = (
-        zephyr_linker_section_configure(section=section_name, align="@APP_SHARED_ALIGN_BYTES@") +
+        zephyr_linker_section_configure(section=section_name, align="@APP_SHARED_ALIGN@") +
         zephyr_linker_section_configure(section=section_name, symbols="_app_smem{section}_end") )
 
     empty_app_smem = (
-        zephyr_linker_section(name=section_name, group="APP_SMEM_GROUP", align="@APP_SHARED_ALIGN_BYTES@", noinput=True, align_with_input=True) +
+        zephyr_linker_section(name=section_name, group="APP_SMEM_GROUP", align="@APP_SHARED_ALIGN@", noinput=True, align_with_input=True) +
         zephyr_linker_section_configure(section = section_name, symbols="_app_smem{section}_start") +
         zephyr_linker_section_configure(section = section_name, symbols="_app_smem{section}_end") )