From a5f3a7fbcb71caa246e70d1dcb6f3c4bfb137221 Mon Sep 17 00:00:00 2001
From: Keith Packard <keithp@keithp.com>
Date: Tue, 9 May 2023 22:09:57 -0700
Subject: [PATCH] cmake/linker_script: Fix cmake linker scripts to define _end

The generated scripts don't include a definition for any symbol indicating
the end of statically allocated memory (such as "_end"). Add a shared cmake
fragment, ram-end.cmake, which contains the necessary instructions to
define _end and z_mapped_end consistently to align with the other sample
linker scripts.

Signed-off-by: Keith Packard <keithp@keithp.com>
(cherry picked from commit bbec614b78b3a083fc7a559ae3ac00a5af24973d)
---
 cmake/linker_script/arm/linker.cmake     | 2 ++
 cmake/linker_script/common/ram-end.cmake | 7 +++++++
 2 files changed, 9 insertions(+)
 create mode 100644 cmake/linker_script/common/ram-end.cmake

diff --git a/cmake/linker_script/arm/linker.cmake b/cmake/linker_script/arm/linker.cmake
index b7d736f00bf04d..15a2ebd1130e35 100644
--- a/cmake/linker_script/arm/linker.cmake
+++ b/cmake/linker_script/arm/linker.cmake
@@ -135,6 +135,8 @@ if(NOT CONFIG_USERSPACE)
   zephyr_linker_section_configure(SECTION .noinit INPUT ".kernel_noinit.*")
 endif()
 
+include(${COMMON_ZEPHYR_LINKER_DIR}/ram-end.cmake)
+
 zephyr_linker_symbol(OBJECT REGION_RAM SYMBOL __kernel_ram_start EXPR "(@__bss_start@)")
 zephyr_linker_symbol(OBJECT REGION_RAM SYMBOL __kernel_ram_end  EXPR "(${RAM_ADDR} + ${RAM_SIZE})")
 zephyr_linker_symbol(OBJECT REGION_RAM SYMBOL __kernel_ram_size EXPR "(@__kernel_ram_end@ - @__bss_start@)")
diff --git a/cmake/linker_script/common/ram-end.cmake b/cmake/linker_script/common/ram-end.cmake
new file mode 100644
index 00000000000000..bb210e199f6633
--- /dev/null
+++ b/cmake/linker_script/common/ram-end.cmake
@@ -0,0 +1,7 @@
+zephyr_linker_section(NAME .last_ram_section VMA RAM LMA RAM_REGION TYPE BSS)
+zephyr_linker_section_configure(
+  SECTION .last_ram_section
+  INPUT ""
+  SYMBOLS _end z_mapped_end
+  KEEP
+  )