Fixes to HAL memory info calls and docs

MemInfo.s:
 Several places in this code called the HAL or other ATPCS defined functions like memset() and hoped that the overall result was V clear. If any of them accidentally set V (for example a CMP that straddles 0x80000000) you ended up trying to look up an international error at the address of the reason code to OS_Memory.
 Now, explicitly clear V in the non error cases where an ATPCS function was called.
 Change the HAL_PhysInfo call to expect a physical ROM size back as an inclusive range, to match the RAM range subreason code. Add 1 to correct for this. A value of 0 & 0 is taken to mean "no physical ROM" as before.
Middle.s:
 Document that 255 means "no IOMD" or "no VIDC", that's what the HALs have been using since year dot.

Version 5.35, 4.79.2.248. Tagged as 'Kernel-5_35-4_79_2_248'

VersionASM

@@ -13,11 +13,11 @@
                         GBLS    Module_ComponentPath
 Module_MajorVersion     SETS    "5.35"
 Module_Version          SETA    535
-Module_MinorVersion     SETS    "4.79.2.247"
-Module_Date             SETS    "13 Nov 2014"
-Module_ApplicationDate  SETS    "13-Nov-14"
+Module_MinorVersion     SETS    "4.79.2.248"
+Module_Date             SETS    "06 Dec 2014"
+Module_ApplicationDate  SETS    "06-Dec-14"
 Module_ComponentName    SETS    "Kernel"
 Module_ComponentPath    SETS    "castle/RiscOS/Sources/Kernel"
-Module_FullVersion      SETS    "5.35 (4.79.2.247)"
-Module_HelpVersion      SETS    "5.35 (13 Nov 2014) 4.79.2.247"
+Module_FullVersion      SETS    "5.35 (4.79.2.248)"
+Module_HelpVersion      SETS    "5.35 (06 Dec 2014) 4.79.2.248"
                         END

VersionNum

@@ -5,19 +5,19 @@
  *
  */
 #define Module_MajorVersion_CMHG        5.35
-#define Module_MinorVersion_CMHG        4.79.2.247
-#define Module_Date_CMHG                13 Nov 2014
+#define Module_MinorVersion_CMHG        4.79.2.248
+#define Module_Date_CMHG                06 Dec 2014
 
 #define Module_MajorVersion             "5.35"
 #define Module_Version                  535
-#define Module_MinorVersion             "4.79.2.247"
-#define Module_Date                     "13 Nov 2014"
+#define Module_MinorVersion             "4.79.2.248"
+#define Module_Date                     "06 Dec 2014"
 
-#define Module_ApplicationDate          "13-Nov-14"
+#define Module_ApplicationDate          "06-Dec-14"
 
 #define Module_ComponentName            "Kernel"
 #define Module_ComponentPath            "castle/RiscOS/Sources/Kernel"
 
-#define Module_FullVersion              "5.35 (4.79.2.247)"
-#define Module_HelpVersion              "5.35 (13 Nov 2014) 4.79.2.247"
+#define Module_FullVersion              "5.35 (4.79.2.248)"
+#define Module_HelpVersion              "5.35 (06 Dec 2014) 4.79.2.248"
 #define Module_LibraryVersionInfo       "5:35"

s/MemInfo

@@ -238,17 +238,16 @@ MemoryConvert   ROUT
         ; ARMs so far).
         ; *** Also, fix it up to do it page by page.
         TST     r0, #flush_tlb
-        EXIT    EQ                      ; If not flush_tlb, can't have flush_cache
+        BEQ     %FT75                   ; If not flush_tlb, can't have flush_cache
         MOV     r1, r0
         LDR     r0, =ZeroPage
         ARMop   TLB_InvalidateAll,,,r0
         TST     r1, #flush_cache        ; If any page has been made uncacheable in L2 then flush!
-        EXIT    EQ
+        BEQ     %FT75
         LDR     r0, =ZeroPage
         ARMop   Cache_CleanInvalidateAll,,,r0
-;75
-;        Pull    "lr"
-;        MSR     CPSR_c, lr
+75
+        CLRV
         EXIT
 
 80
@@ -266,7 +265,7 @@ MemoryConvert   ROUT
 90
         ADRL    r0, ErrorBlock_BadAddress
 95
-        STR     r0, [sp]
+        STR     r0, [sp, #Proc_RegOffset+0]
         SETV
         EXIT
 
@@ -460,6 +459,7 @@ MemoryPhysSize
         ADD     r1, sp, #4
         CallHAL HAL_PhysInfo
         MOV     r2, #4*1024
+        CLRV
         EXIT
  |
         MOV     r1, #PhysSpaceSize :SHR: ByteShift
@@ -593,6 +593,7 @@ MemoryReadPhys  ROUT
         MOVHS   r2, #(OSROM_ImageSize*1024) :SHR: ByteShift
         BLHS    memset
 
+        CLRV
         EXIT
 
 
@@ -662,7 +663,8 @@ MemoryAmounts   ROUT
         MOV     r2, sp
         CallHAL HAL_PhysInfo
         LDMIA   sp!, {r0-r1}
-        SUB     r1, r1, r0              ; ROM = ROMPhysTop - ROMPhysBot
+        SUBS    r1, r1, r0
+        ADDNE   r1, r1, #1              ; ROM = ROMPhysTop + 1 - ROMPhysBot
         Pull    "r0, sb, ip"
         B       %FT97
 40
@@ -683,6 +685,7 @@ MemoryAmounts   ROUT
 97
         MOV     r1, r1, LSR #12         ; Return as number of pages.
         MOV     r2, #4*1024             ; Return page size.
+        CLRV
         EXIT
 99
         ADRL    r0, ErrorBlock_BadParameters

s/Middle

@@ -1334,12 +1334,15 @@ ReadSysInfo_InvalidReason
 ;               bits 8-15 = I/O control chip type
 ;                               0 => IOC
 ;                               1 => IOMD
+;                             255 => none
 ;               bits 16-23 = memory control chip type
 ;                               0 => MEMC1/MEMC1a
 ;                               1 => IOMD
+;                             255 => none
 ;               bits 24-31 = video control chip type
 ;                               0 => VIDC1a
 ;                               1 => VIDC20
+;                             255 => none
 ;       r1 = hardware configuration word 1
 ;               bits 0-7 = I/O chip type
 ;                               0 => absent
@@ -1350,10 +1353,10 @@ ReadSysInfo_InvalidReason
 ;                               0 => absent
 ;                               1 => present (type 1) eg A4 portable
 ;                               2 => present (type 2) eg Stork portable
-;               bits 8-15 = IOMD variant
+;               bits 8-15 = IOMD variant (when marked as present in word 0)
 ;                               0 => IOMD
 ;                               1 => IOMDL ie ARM7500 (Morris)
-;               bits 16-23 = VIDC20 variant
+;               bits 16-23 = VIDC20 variant (when marked as present in word 0)
 ;                               0 => VIDC20
 ;                               1 => VIDC2L ie ARM7500 (Morris)
 ;               bits 24-31 = miscellaneous flags