STYLE: code comments

src/Allwmake

 #!/bin/sh
 cd "${0%/*}" || exit                            # Run from this directory
+. "${WM_PROJECT_DIR:?}"/wmake/scripts/AllwmakeParseArguments
 #------------------------------------------------------------------------------
 
 petsc4Foam/Allwmake $*

src/petsc4Foam/utils/petscCacheManager.H

@@ -40,7 +40,7 @@ Description
         {
             matrix
             {
-                update  always;
+                update  always;  // (default: always)
             }
 
             preconditioner
@@ -86,22 +86,23 @@ struct Caching
         //- Caching update types
         enum updateTypes
         {
-            Always,         //!< "always" update every time-step
+            Always,         //!< "always" update every time-step [default]
             Periodic,       //!< "periodic" update at given period
             Adaptive,       //!< "adaptive" update scheme
-            Never,          //!< "never" update
-            None = Never,   //!< "none" is an alias for "never"
+            Never,          //!< "never" update (or "none")
         };
 
 
-        //- Names for selectable caching types
+        //- Names for the update types
         static const Enum<updateTypes> updateTypeNames_;
 
 
     // Member Data
 
+        //- Caching update
         updateTypes updateType_;
 
+        //- Cache update frequency (for Periodic)
         int updateFreq_;
 
         //- Elapsed time (s) for current iteration
@@ -281,7 +282,7 @@ private:
                     const double ratio1 =
                         precondCaching.time1 / precondCaching.timeIter;
 
-                    int nsteps =
+                    const int nsteps =
                         min(1e5, ratio0 * (1. / mag(1. - ratio1 + 1e-6)));
 
                     if (iter >= nsteps)