From 624e051372167ea13acf0efa7447f6ee840eefb0 Mon Sep 17 00:00:00 2001
From: TOKITA Hiroshi <tokita.hiroshi@gmail.com>
Date: Sat, 15 Jun 2024 11:16:38 +0900
Subject: [PATCH] linker: devicetree_regions: Add support memory region flag
 setting

Add `zephyr,memory-region-flags` for supporting memory region flags
setting.

For example, when the below node is in the devicetree,

```
    test_sram: sram@20010000 {
        compatible = "zephyr,memory-region", "mmio-sram";
        reg = < 0x20010000 0x1000 >;
        zephyr,memory-region = "FOOBAR";
        zephyr,memory-region-flags = "rw";
    };
```

We get the following line in MEMORY section of linker script.

```
FOOBAR (rw) : ORIGIN = (0x20010000), LENGTH = (0x1000)
```

Signed-off-by: TOKITA Hiroshi <tokita.hiroshi@gmail.com>
---
 cmake/linker_script/arm/linker.cmake        |  3 +-
 cmake/modules/extensions.cmake              | 61 +++++++++++-------
 dts/bindings/base/zephyr,memory-common.yaml |  7 +++
 include/zephyr/linker/devicetree_regions.h  | 70 +++++++++++++++++++--
 4 files changed, 112 insertions(+), 29 deletions(-)

diff --git a/cmake/linker_script/arm/linker.cmake b/cmake/linker_script/arm/linker.cmake
index bb501a16cdb..ad639f373cc 100644
--- a/cmake/linker_script/arm/linker.cmake
+++ b/cmake/linker_script/arm/linker.cmake
@@ -41,10 +41,9 @@ zephyr_linker_memory(NAME FLASH    FLAGS rx START ${FLASH_ADDR} SIZE ${FLASH_SIZ
 zephyr_linker_memory(NAME RAM      FLAGS wx START ${RAM_ADDR}   SIZE ${RAM_SIZE})
 zephyr_linker_memory(NAME IDT_LIST FLAGS wx START ${IDT_ADDR}   SIZE 2K)
 
-# Only use 'rw' as FLAGS. It's not used anyway.
 dt_comp_path(paths COMPATIBLE "zephyr,memory-region")
 foreach(path IN LISTS paths)
-  zephyr_linker_dts_memory(PATH ${path} FLAGS rw)
+  zephyr_linker_dts_memory(PATH ${path})
 endforeach()
 
 if(CONFIG_XIP)
diff --git a/cmake/modules/extensions.cmake b/cmake/modules/extensions.cmake
index b91566024ef..ab1f6f59cda 100644
--- a/cmake/modules/extensions.cmake
+++ b/cmake/modules/extensions.cmake
@@ -4633,7 +4633,7 @@ function(zephyr_linker)
 endfunction()
 
 # Usage:
-#   zephyr_linker_memory(NAME <name> START <address> SIZE <size> FLAGS <flags>)
+#   zephyr_linker_memory(NAME <name> START <address> SIZE <size> [FLAGS <flags>])
 #
 # Zephyr linker memory.
 # This function specifies a memory region for the platform in use.
@@ -4650,14 +4650,18 @@ endfunction()
 #                  All the following are valid values:
 #                    1048576, 0x10000, 1024k, 1024K, 1m, and 1M.
 # FLAGS <flags>  : Flags describing properties of the memory region.
-#                  Currently supported:
 #                  r: Read-only region
 #                  w: Read-write region
 #                  x: Executable region
-#                  The flags r and x, or w and x may be combined like: rx, wx.
+#                  a: Allocatable region
+#                  i: Initialized region
+#                  l: Same as ‘i’
+#                  !: Invert the sense of any of the attributes that follow
+#                  The flags may be combined like: rx, rx!w.
 function(zephyr_linker_memory)
-  set(single_args "FLAGS;NAME;SIZE;START")
-  cmake_parse_arguments(MEMORY "" "${single_args}" "" ${ARGN})
+  set(req_single_args "NAME;SIZE;START")
+  set(single_args "FLAGS")
+  cmake_parse_arguments(MEMORY "" "${req_single_args};${single_args}" "" ${ARGN})
 
   if(MEMORY_UNPARSED_ARGUMENTS)
     message(FATAL_ERROR "zephyr_linker_memory(${ARGV0} ...) given unknown "
@@ -4665,7 +4669,7 @@ function(zephyr_linker_memory)
     )
   endif()
 
-  foreach(arg ${single_args})
+  foreach(arg ${req_single_args})
     if(NOT DEFINED MEMORY_${arg})
       message(FATAL_ERROR "zephyr_linker_memory(${ARGV0} ...) missing required "
                           "argument: ${arg}"
@@ -4674,6 +4678,7 @@ function(zephyr_linker_memory)
   endforeach()
 
   set(MEMORY)
+  zephyr_linker_arg_val_list(MEMORY "${req_single_args}")
   zephyr_linker_arg_val_list(MEMORY "${single_args}")
 
   string(REPLACE ";" "\;" MEMORY "${MEMORY}")
@@ -4683,7 +4688,7 @@ function(zephyr_linker_memory)
 endfunction()
 
 # Usage:
-#   zephyr_linker_memory_ifdef(<setting> NAME <name> START <address> SIZE <size> FLAGS <flags>)
+#   zephyr_linker_memory_ifdef(<setting> NAME <name> START <address> SIZE <size> [FLAGS <flags>])
 #
 # Will create memory region if <setting> is enabled.
 #
@@ -4746,9 +4751,9 @@ function(zephyr_linker_dts_section)
 endfunction()
 
 # Usage:
-#   zephyr_linker_dts_memory(PATH <path> FLAGS <flags>)
-#   zephyr_linker_dts_memory(NODELABEL <nodelabel> FLAGS <flags>)
-#   zephyr_linker_dts_memory(CHOSEN <prop> FLAGS <flags>)
+#   zephyr_linker_dts_memory(PATH <path>)
+#   zephyr_linker_dts_memory(NODELABEL <nodelabel>)
+#   zephyr_linker_dts_memory(CHOSEN <prop>)
 #
 # Zephyr linker devicetree memory.
 # This function specifies a memory region for the platform in use based on its
@@ -4763,15 +4768,9 @@ endfunction()
 # NODELABEL <label>: Node label
 # CHOSEN <prop>    : Chosen property, add memory section described by the
 #                    /chosen property if it exists.
-# FLAGS <flags>  : Flags describing properties of the memory region.
-#                  Currently supported:
-#                  r: Read-only region
-#                  w: Read-write region
-#                  x: Executable region
-#                  The flags r and x, or w and x may be combined like: rx, wx.
 #
 function(zephyr_linker_dts_memory)
-  set(single_args "CHOSEN;FLAGS;PATH;NODELABEL")
+  set(single_args "CHOSEN;PATH;NODELABEL")
   cmake_parse_arguments(DTS_MEMORY "" "${single_args}" "" ${ARGN})
 
   if(DTS_MEMORY_UNPARSED_ARGUMENTS)
@@ -4814,12 +4813,28 @@ function(zephyr_linker_dts_memory)
   endif()
   zephyr_string(SANITIZE name ${name})
 
-  zephyr_linker_memory(
-    NAME  ${name}
-    START ${addr}
-    SIZE  ${size}
-    FLAGS ${DTS_MEMORY_FLAGS}
-  )
+  dt_prop(flags PATH ${DTS_MEMORY_PATH} PROPERTY "zephyr,memory-region-flags")
+  if(NOT DEFINED flags)
+    zephyr_linker_memory(
+      NAME  ${name}
+      START ${addr}
+      SIZE  ${size}
+      FLAGS "rw"
+    )
+  elseif("${flags}" STREQUAL "")
+    zephyr_linker_memory(
+      NAME  ${name}
+      START ${addr}
+      SIZE  ${size}
+    )
+  else()
+    zephyr_linker_memory(
+      NAME  ${name}
+      START ${addr}
+      SIZE  ${size}
+      FLAGS ${flags}
+    )
+  endif()
 endfunction()
 
 # Usage:
diff --git a/dts/bindings/base/zephyr,memory-common.yaml b/dts/bindings/base/zephyr,memory-common.yaml
index f2ccbdb3c41..8dff47600d1 100644
--- a/dts/bindings/base/zephyr,memory-common.yaml
+++ b/dts/bindings/base/zephyr,memory-common.yaml
@@ -12,6 +12,13 @@ properties:
       is taken from the <reg> property, while the name is the value of
       this property.
 
+  zephyr,memory-region-flags:
+    type: string
+    description: |
+      Set attributes such as read-only or executable for the linker script
+      memory region. The string set here will be specified in parentheses
+      after the area name in the linker script.
+
   zephyr,memory-region-mpu:
     type: string
     deprecated: true
diff --git a/include/zephyr/linker/devicetree_regions.h b/include/zephyr/linker/devicetree_regions.h
index e1d91627bb0..9a0139dfc8e 100644
--- a/include/zephyr/linker/devicetree_regions.h
+++ b/include/zephyr/linker/devicetree_regions.h
@@ -82,6 +82,66 @@
 #define LINKER_DT_NODE_REGION_NAME(node_id) \
 	STRINGIFY(LINKER_DT_NODE_REGION_NAME_TOKEN(node_id))
 
+#define _DT_MEMORY_REGION_FLAGS_TOKEN(n)    DT_STRING_TOKEN(n, zephyr_memory_region_flags)
+#define _DT_MEMORY_REGION_FLAGS_UNQUOTED(n) DT_STRING_UNQUOTED(n, zephyr_memory_region_flags)
+
+#define _LINKER_L_PAREN (
+#define _LINKER_R_PAREN )
+#define _LINKER_ENCLOSE_PAREN(x) _LINKER_L_PAREN x _LINKER_R_PAREN
+
+#define _LINKER_IS_EMPTY_TOKEN_          1
+#define _LINKER_IS_EMPTY_TOKEN_EXPAND(x) _LINKER_IS_EMPTY_TOKEN_##x
+#define _LINKER_IS_EMPTY_TOKEN(x)        _LINKER_IS_EMPTY_TOKEN_EXPAND(x)
+
+/**
+ * @brief Get the linker memory-region flags with parentheses.
+ *
+ * This attempts to return the zephyr,memory-region-flags property
+ * with parentheses.
+ * Return empty string if not set the property.
+ *
+ * Example devicetree fragment:
+ *
+ * @code{.dts}
+ *     / {
+ *             soc {
+ *                     rx: memory@2000000 {
+ *                             zephyr,memory-region = "READ_EXEC";
+ *                             zephyr,memory-region-flags = "rx";
+ *                     };
+ *                     rx_not_w: memory@2001000 {
+ *                             zephyr,memory-region = "READ_EXEC_NOT_WRITE";
+ *                             zephyr,memory-region-flags = "rx!w";
+ *                     };
+ *                     no_flags: memory@2001000 {
+ *                             zephyr,memory-region = "NO_FLAGS";
+ *                     };
+ *             };
+ *     };
+ * @endcode
+ *
+ * Example usage:
+ *
+ * @code{.c}
+ *    LINKER_DT_NODE_REGION_FLAGS(DT_NODELABEL(rx))       // (rx)
+ *    LINKER_DT_NODE_REGION_FLAGS(DT_NODELABEL(rx_not_w)) // (rx!w)
+ *    LINKER_DT_NODE_REGION_FLAGS(DT_NODELABEL(no_flags)) // [flags will not be specified]
+ * @endcode
+ *
+ * @param node_id node identifier
+ * @return the value of the memory region flag specified in the device tree
+ *         enclosed in parentheses.
+ */
+
+#define LINKER_DT_NODE_REGION_FLAGS(node_id)                                                       \
+	COND_CODE_1(DT_NODE_HAS_PROP(node_id, zephyr_memory_region_flags),                         \
+		    (COND_CODE_1(_LINKER_IS_EMPTY_TOKEN(_DT_MEMORY_REGION_FLAGS_TOKEN(node_id)),   \
+				 (),                                                               \
+				 (_LINKER_ENCLOSE_PAREN(                                           \
+					_DT_MEMORY_REGION_FLAGS_UNQUOTED(node_id))                 \
+				 ))),                                                              \
+		    (_LINKER_ENCLOSE_PAREN(rw)))
+
 /** @cond INTERNAL_HIDDEN */
 
 #define _DT_COMPATIBLE	zephyr_memory_region
@@ -102,6 +162,7 @@
  *        compatible = "zephyr,memory-region", "mmio-sram";
  *        reg = < 0x20010000 0x1000 >;
  *        zephyr,memory-region = "FOOBAR";
+ *        zephyr,memory-region-flags = "rw";
  *    };
  * @endcode
  *
@@ -114,10 +175,11 @@
  * @param node_id devicetree node identifier
  * @param attr region attributes
  */
-#define _REGION_DECLARE(node_id)			\
-	LINKER_DT_NODE_REGION_NAME_TOKEN(node_id) :	\
-	ORIGIN = DT_REG_ADDR(node_id),			\
-	LENGTH = DT_REG_SIZE(node_id)
+#define _REGION_DECLARE(node_id)                                                                   \
+	LINKER_DT_NODE_REGION_NAME_TOKEN(node_id)                                                  \
+	LINKER_DT_NODE_REGION_FLAGS(node_id)                                                       \
+		: ORIGIN = DT_REG_ADDR(node_id),                                                   \
+		  LENGTH = DT_REG_SIZE(node_id)
 
 /**
  * @brief Declare a memory section from the device tree nodes with