Try adding a define to the documentation

Documentation/pal/pal.h

@@ -1,4 +0,0 @@
-PAL ABI Documentation
-=====================
-
-.. doxygenfunction:: DkVirtualMemoryAlloc

Documentation/pal/pal.rst

@@ -0,0 +1,12 @@
+PAL ABI Documentation
+=====================
+
+.. doxygenfunction:: DkVirtualMemoryAlloc
+
+This function accepts the following constants as the alloc_type argument.
+
+.. doxygendefine:: PAL_ALLOC_COMMIT
+
+.. doxygendefine:: PAL_ALLOC_RESERVE
+
+.. doxygendefine:: PAL_ALLOC_INTERNAL

Pal/src/pal.h

@@ -233,11 +233,19 @@ PAL_CONTROL * pal_control_addr (void);
  */
 
 /* Memory Allocation Types */
-#define PAL_ALLOC_COMMIT      0x0000   /* Actually allocate the memory */
-#define PAL_ALLOC_RESERVE     0x0001   /* Only reserve the memory */
-
+/*!
+ * \brief Actually allocate the memory.
+ */
+#define PAL_ALLOC_COMMIT      0x0000
+/*!
+ * \brief Only reserve the memory
+ */
+#define PAL_ALLOC_RESERVE     0x0001
+/*!
+ * \brief For PAL-internal use.
+ */
 #ifdef IN_PAL
-#define PAL_ALLOC_INTERNAL    0x8000   /* For PAL-internal use */
+#define PAL_ALLOC_INTERNAL    0x8000
 #endif
 
 /* Memory Protection Flags */