MLECO-2983: Preliminary support to allow semihosting

Adding basic support to allow applications to build with semihosting
support. Default state is always disabled.

Signed-off-by: Kshitij Sisodia <kshitij.sisodia@arm.com>
Change-Id: I1d34c3a246560aaffcb34eee801e1a87d887d559

5 files changed, 27 insertions, 3 deletions

diff --git a/scripts/cmake/toolchains/bare-metal-armclang.cmake b/scripts/cmake/toolchains/bare-metal-armclang.cmake
index 065395b..9752053 100644
--- a/scripts/cmake/toolchains/bare-metal-armclang.cmake
+++ b/scripts/cmake/toolchains/bare-metal-armclang.cmake
@@ -96,6 +96,12 @@ add_link_options(
     --xref
     "$<$<CONFIG:RELEASE>:--no_debug>")
 
+function(configure_semihosting TARGET_NAME SEMIHOSTING)
+    if (${SEMIHOSTING})
+        target_compile_definitions(${TARGET_NAME} PUBLIC USE_SEMIHOSTING)
+    endif()
+endfunction()
+
 # Function to add a map file output for the linker to dump diagnostic information to.
 function(add_target_map_file TARGET_NAME MAP_FILE_PATH)
     target_link_options(${TARGET_NAME} PUBLIC
diff --git a/scripts/cmake/toolchains/bare-metal-gcc.cmake b/scripts/cmake/toolchains/bare-metal-gcc.cmake
index 89201fb..a5688d6 100644
--- a/scripts/cmake/toolchains/bare-metal-gcc.cmake
+++ b/scripts/cmake/toolchains/bare-metal-gcc.cmake
@@ -85,11 +85,21 @@ add_link_options(
     -mcpu=${CPU_NAME}
     -mfloat-abi=${FLOAT_ABI}
     -mlittle-endian
-    --specs=nosys.specs
     --stats
     "SHELL:-Xlinker --gc-sections"
     "$<$<CONFIG:RELEASE>:--no-debug>")
 
+function(configure_semihosting TARGET_NAME SEMIHOSTING)
+    if (${SEMIHOSTING})
+        target_link_options(${TARGET_NAME} PUBLIC "--specs=rdimon.specs")
+        target_compile_options(${TARGET_NAME} PUBLIC "--specs=rdimon.specs")
+        target_compile_definitions(${TARGET_NAME} PUBLIC USE_SEMIHOSTING)
+    else()
+        target_link_options(${TARGET_NAME} PUBLIC --specs=nosys.specs)
+        target_compile_options(${TARGET_NAME} PUBLIC "--specs=nosys.specs")
+    endif()
+endfunction()
+
 # Function to add a map file output for the linker to dump diagnostic information to.
 function(add_target_map_file TARGET_NAME MAP_FILE_PATH)
     target_link_options(${TARGET_NAME} PUBLIC
diff --git a/source/hal/cmsis_device/CMakeLists.txt b/source/hal/cmsis_device/CMakeLists.txt
index 255bd30..b98feb2 100644
--- a/source/hal/cmsis_device/CMakeLists.txt
+++ b/source/hal/cmsis_device/CMakeLists.txt
@@ -56,13 +56,18 @@ target_sources(${CMSIS_DEVICE_TARGET}
 # Device definition needs to be set, is checked in source files to include correct header
 target_compile_definitions(${CMSIS_DEVICE_TARGET} PUBLIC ${ARM_CPU})
 
-
 # Tell linker that reset interrupt handler is our entry point
 target_link_options(
     ${CMSIS_DEVICE_TARGET}
     INTERFACE
     --entry Reset_Handler)
 
+# Check if semihosting configuration is available
+if (COMMAND configure_semihosting)
+    option(USE_SEMIHOSTING "Enable/disable semihosting option" OFF)
+    configure_semihosting(${CMSIS_DEVICE_TARGET} ${USE_SEMIHOSTING})
+endif()
+
 # 4 Display status:
 message(STATUS "CMAKE_CURRENT_SOURCE_DIR: " ${CMAKE_CURRENT_SOURCE_DIR})
 message(STATUS "*******************************************************")
diff --git a/source/hal/platform/mps3/source/platform_drivers.c b/source/hal/platform/mps3/source/platform_drivers.c
index 3046c12..fc119ab 100644
--- a/source/hal/platform/mps3/source/platform_drivers.c
+++ b/source/hal/platform/mps3/source/platform_drivers.c
@@ -17,9 +17,9 @@
 
 #include "platform_drivers.h"
 
-#include "uart_stdout.h"    /* stdout over UART. */
 #include "log_macros.h"     /* Logging functions */
 #include "device_mps3.h"    /* FPGA level definitions and functions. */
+#include "uart_stdout.h"    /* stdout over UART. */
 
 #include <string.h>         /* For strncpy */
 
diff --git a/source/hal/profiles/bare-metal/bsp/retarget.c b/source/hal/profiles/bare-metal/bsp/retarget.c
index dfef62c..9ed3004 100644
--- a/source/hal/profiles/bare-metal/bsp/retarget.c
+++ b/source/hal/profiles/bare-metal/bsp/retarget.c
@@ -14,6 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+#if !defined(USE_SEMIHOSTING)
 
 #include "uart_stdout.h"
 
@@ -266,3 +267,5 @@ int ferror(FILE *f)
 }
 
 #endif /* #ifndef ferror */
+
+#endif /* !defined(USE_SEMIHOSTING) */