Increase RamFS limit to 2GB

Detail:
RamFS now supports disc sizes up to 2GB-4KB, so raise the dynamic area limit from 508MB.

Admin:
Tested with a disc size up to 928MB

Version 6.46. Tagged as 'Kernel-6_46'

VersionASM

@@ -9,12 +9,12 @@
                         GBLS    Module_ApplicationDate
                         GBLS    Module_HelpVersion
                         GBLS    Module_ComponentName
-Module_MajorVersion     SETS    "6.45"
-Module_Version          SETA    645
+Module_MajorVersion     SETS    "6.46"
+Module_Version          SETA    646
 Module_MinorVersion     SETS    ""
-Module_Date             SETS    "28 Oct 2020"
-Module_ApplicationDate  SETS    "28-Oct-20"
+Module_Date             SETS    "23 Nov 2020"
+Module_ApplicationDate  SETS    "23-Nov-20"
 Module_ComponentName    SETS    "Kernel"
-Module_FullVersion      SETS    "6.45"
-Module_HelpVersion      SETS    "6.45 (28 Oct 2020)"
+Module_FullVersion      SETS    "6.46"
+Module_HelpVersion      SETS    "6.46 (23 Nov 2020)"
                         END

VersionNum

-/* (6.45)
+/* (6.46)
  *
  * This file is automatically maintained by srccommit, do not edit manually.
  *
  */
-#define Module_MajorVersion_CMHG        6.45
+#define Module_MajorVersion_CMHG        6.46
 #define Module_MinorVersion_CMHG
-#define Module_Date_CMHG                28 Oct 2020
+#define Module_Date_CMHG                23 Nov 2020
 
-#define Module_MajorVersion             "6.45"
-#define Module_Version                  645
+#define Module_MajorVersion             "6.46"
+#define Module_Version                  646
 #define Module_MinorVersion             ""
-#define Module_Date                     "28 Oct 2020"
+#define Module_Date                     "23 Nov 2020"
 
-#define Module_ApplicationDate          "28-Oct-20"
+#define Module_ApplicationDate          "23-Nov-20"
 
 #define Module_ComponentName            "Kernel"
 
-#define Module_FullVersion              "6.45"
-#define Module_HelpVersion              "6.45 (28 Oct 2020)"
-#define Module_LibraryVersionInfo       "6:45"
+#define Module_FullVersion              "6.46"
+#define Module_HelpVersion              "6.46 (23 Nov 2020)"
+#define Module_LibraryVersionInfo       "6:46"

s/ChangeDyn

@@ -6873,8 +6873,9 @@ DynAreaHandler_RAMDisc ROUT
         ; Claim empty space
         MOV     r0, #DAReason_PMP_Resize
       [ {TRUE}
-        ; Limit max size to ~512MB - RAMFS currently can't cope with more than that
-        RSB     r2, r6, #508<<(20-12)
+        ; Limit max size to 2GB-4KB - RAMFS and other bits of the OS won't go past that currently
+        LDR     r2, =DynArea_PMP_BigByteCount:SHR:12
+        SUB     r2, r2, r6 ; R2 = pages left till maximum
         CMP     r10, r2
         MOVGT   r10, r2
       ]