GHS: Document usage of GHS_NO_SOURCE_GROUP_FILE

-- Also change variable name to CMAKE_GHS_NO_SOURCE_GROUP_FILE
diff --git a/Help/generator/Green Hills MULTI.rst b/Help/generator/Green Hills MULTI.rst
index bfe671f..e474682 100644
--- a/Help/generator/Green Hills MULTI.rst
+++ b/Help/generator/Green Hills MULTI.rst
@@ -59,6 +59,7 @@
 The following properties are available:
 
 * :prop_tgt:`GHS_INTEGRITY_APP`
+* :prop_tgt:`GHS_NO_SOURCE_GROUP_FILE`
 
 .. note::
   This generator is deemed experimental as of CMake |release|
diff --git a/Help/manual/cmake-properties.7.rst b/Help/manual/cmake-properties.7.rst
index e1de134..4366c0d 100644
--- a/Help/manual/cmake-properties.7.rst
+++ b/Help/manual/cmake-properties.7.rst
@@ -195,6 +195,7 @@
    /prop_tgt/FRAMEWORK_VERSION
    /prop_tgt/GENERATOR_FILE_NAME
    /prop_tgt/GHS_INTEGRITY_APP
+   /prop_tgt/GHS_NO_SOURCE_GROUP_FILE
    /prop_tgt/GNUtoMS
    /prop_tgt/HAS_CXX
    /prop_tgt/IMPLICIT_DEPENDS_INCLUDE_TRANSFORM
diff --git a/Help/manual/cmake-variables.7.rst b/Help/manual/cmake-variables.7.rst
index 1698734..83c88a5 100644
--- a/Help/manual/cmake-variables.7.rst
+++ b/Help/manual/cmake-variables.7.rst
@@ -345,6 +345,7 @@
    /variable/CMAKE_FOLDER
    /variable/CMAKE_Fortran_FORMAT
    /variable/CMAKE_Fortran_MODULE_DIRECTORY
+   /variable/CMAKE_GHS_NO_SOURCE_GROUP_FILE
    /variable/CMAKE_GLOBAL_AUTOGEN_TARGET
    /variable/CMAKE_GLOBAL_AUTOGEN_TARGET_NAME
    /variable/CMAKE_GLOBAL_AUTORCC_TARGET
diff --git a/Help/prop_tgt/GHS_NO_SOURCE_GROUP_FILE.rst b/Help/prop_tgt/GHS_NO_SOURCE_GROUP_FILE.rst
new file mode 100644
index 0000000..11ce0b22
--- /dev/null
+++ b/Help/prop_tgt/GHS_NO_SOURCE_GROUP_FILE.rst
@@ -0,0 +1,13 @@
+GHS_NO_SOURCE_GROUP_FILE
+------------------------
+
+``ON`` / ``OFF`` boolean to control if the project file for a target should
+be one single file or multiple files.
+
+The default behavior or when the property is ``OFF`` is to generate a project
+file for the target and then a sub-project file for each source group.
+
+When this property is ``ON`` or if :variable:`CMAKE_GHS_NO_SOURCE_GROUP_FILE`
+is ``ON`` then only a single project file is generated for the target.
+
+Supported on :generator:`Green Hills MULTI`.
diff --git a/Help/variable/CMAKE_GHS_NO_SOURCE_GROUP_FILE.rst b/Help/variable/CMAKE_GHS_NO_SOURCE_GROUP_FILE.rst
new file mode 100644
index 0000000..b6768a1
--- /dev/null
+++ b/Help/variable/CMAKE_GHS_NO_SOURCE_GROUP_FILE.rst
@@ -0,0 +1,6 @@
+CMAKE_GHS_NO_SOURCE_GROUP_FILE
+------------------------------
+
+``ON`` / ``OFF`` boolean to control if the project file for a target should
+be one single file or multiple files.  Refer to
+:prop_tgt:`GHS_NO_SOURCE_GROUP_FILE` for further details.
diff --git a/Source/cmGhsMultiTargetGenerator.cxx b/Source/cmGhsMultiTargetGenerator.cxx
index 04a8b3c..5fe350c 100644
--- a/Source/cmGhsMultiTargetGenerator.cxx
+++ b/Source/cmGhsMultiTargetGenerator.cxx
@@ -454,7 +454,7 @@
       cmSystemTools::IsOn(
         this->GeneratorTarget->GetProperty("GHS_NO_SOURCE_GROUP_FILE")) ||
       cmSystemTools::IsOn(
-        this->Makefile->GetDefinition("GHS_NO_SOURCE_GROUP_FILE"));
+        this->Makefile->GetDefinition("CMAKE_GHS_NO_SOURCE_GROUP_FILE"));
     if (useProjectFile || sg.empty()) {
       fout = &fout_proj;
     } else {
diff --git a/Tests/CMakeLists.txt b/Tests/CMakeLists.txt
index ed98d97..6c888cc 100644
--- a/Tests/CMakeLists.txt
+++ b/Tests/CMakeLists.txt
@@ -2368,7 +2368,7 @@
       add_test_GhsMulti_rename_install(EXEC_AND_LIB)
       add_test_GhsMulti(multiple_source_groups GhsMultiSrcGroups Default "")
       add_test_GhsMulti(multiple_source_groups_folders GhsMultiSrcGroups PropFolders "-DTEST_PROP=ON")
-      add_test_GhsMulti(multiple_source_groups_all_folders GhsMultiSrcGroups AllFolders "-DGHS_NO_SOURCE_GROUP_FILE=ON")
+      add_test_GhsMulti(multiple_source_groups_all_folders GhsMultiSrcGroups AllFolders "-DCMAKE_GHS_NO_SOURCE_GROUP_FILE=ON")
       add_test_GhsMulti(unsupported_targets GhsMultiUnsupportedTargets "" "")
       add_test_GhsMulti(object_library GhsMultiObjectLibrary "" "")
       add_test_GhsMulti(exclude GhsMultiExclude "" ""