Thread: [fuse-emulator-cvs] SF.net SVN: fuse-emulator:[4422] branches/2011-05-04-memory/fuse

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Revision: 4422
          http://fuse-emulator.svn.sourceforge.net/fuse-emulator/?rev=4422&view=rev
Author:   pak21
Date:     2011-05-04 23:02:33 +0000 (Wed, 04 May 2011)

Log Message:
-----------
First bits of general memory page sizing.
NB: don't even consider changing the page size yet!

Modified Paths:
--------------
    branches/2011-05-04-memory/fuse/hacking/ChangeLog
    branches/2011-05-04-memory/fuse/memory.c
    branches/2011-05-04-memory/fuse/memory.h
    branches/2011-05-04-memory/fuse/peripherals/ula.c

Modified: branches/2011-05-04-memory/fuse/hacking/ChangeLog
===================================================================

--- branches/2011-05-04-memory/fuse/hacking/ChangeLog	2011-05-04 22:41:32 UTC (rev 4421)
+++ branches/2011-05-04-memory/fuse/hacking/ChangeLog	2011-05-04 23:02:33 UTC (rev 4422)
@@ -3629,3 +3629,5 @@
          along with older autotools (patch #3295662) (thanks, Tomáš Franke)
          (Sergio Baldoví)
 20110504 tape.c: fix warnings.
+20110505 memory.[ch],peripherals/ula.c: first bits of general memory page
+         sizing.

Modified: branches/2011-05-04-memory/fuse/memory.c
===================================================================
--- branches/2011-05-04-memory/fuse/memory.c	2011-05-04 22:41:32 UTC (rev 4421)
+++ branches/2011-05-04-memory/fuse/memory.c	2011-05-04 23:02:33 UTC (rev 4422)
@@ -52,15 +52,15 @@
 int memory_source_any; /* Used by the debugger to signify an absolute address */
 int memory_source_none; /* No memory attached here */
 
-/* Each 8Kb RAM chunk accessible by the Z80 */
-memory_page memory_map_read[8];
-memory_page memory_map_write[8];
+/* Each RAM chunk accessible by the Z80 */
+memory_page memory_map_read[MEMORY_PAGES_IN_64K];
+memory_page memory_map_write[MEMORY_PAGES_IN_64K];
 
 /* Mappings for the 'home' (normal ROM/RAM) pages, the Timex DOCK and
    the Timex EXROM */
-memory_page *memory_map_home[8];
-memory_page *memory_map_dock[8];
-memory_page *memory_map_exrom[8];
+memory_page *memory_map_home[MEMORY_PAGES_IN_64K];
+memory_page *memory_map_dock[MEMORY_PAGES_IN_64K];
+memory_page *memory_map_exrom[MEMORY_PAGES_IN_64K];
 
 /* Standard mappings for the 'normal' RAM */
 memory_page memory_map_ram[ 2 * SPECTRUM_RAM_PAGES ];
@@ -256,7 +256,7 @@
   libspectrum_word bank;
   memory_page *mapping;
 
-  bank = address >> 13;
+  bank = address >> MEMORY_PAGE_SIZE_LOGARITHM;
   mapping = &memory_map_read[ bank ];
 
   if( debugger_mode != DEBUGGER_MODE_INACTIVE )
@@ -268,7 +268,7 @@
   if( opus_active && address >= 0x2800 && address < 0x3800 )
     return opus_read( address );
 
-  return mapping->page[ address & 0x1fff ];
+  return mapping->page[ address & MEMORY_PAGE_SIZE_MASK ];
 }
 
 void
@@ -277,7 +277,7 @@
   libspectrum_word bank;
   memory_page *mapping;
 
-  bank = address >> 13;
+  bank = address >> MEMORY_PAGE_SIZE_LOGARITHM;
   mapping = &memory_map_write[ bank ];
 
   if( debugger_mode != DEBUGGER_MODE_INACTIVE )
@@ -294,9 +294,9 @@
 memory_display_dirty_pentagon_16_col( libspectrum_word address,
                                       libspectrum_byte b )
 {
-  libspectrum_word bank = address >> 13;
+  libspectrum_word bank = address >> MEMORY_PAGE_SIZE_LOGARITHM;
   memory_page *mapping = &memory_map_write[ bank ];
-  libspectrum_word offset = address & 0x1fff;
+  libspectrum_word offset = address & MEMORY_PAGE_SIZE_MASK;
   libspectrum_byte *memory = mapping->page;
 
   /* The offset into the 16Kb RAM page (as opposed to the 8Kb chunk) */
@@ -321,9 +321,9 @@
 void
 memory_display_dirty_sinclair( libspectrum_word address, libspectrum_byte b ) \
 {
-  libspectrum_word bank = address >> 13;
+  libspectrum_word bank = address >> MEMORY_PAGE_SIZE_LOGARITHM;
   memory_page *mapping = &memory_map_write[ bank ];
-  libspectrum_word offset = address & 0x1fff;
+  libspectrum_word offset = address & MEMORY_PAGE_SIZE_MASK;
   libspectrum_byte *memory = mapping->page;
 
   /* The offset into the 16Kb RAM page (as opposed to the 8Kb chunk) */
@@ -343,7 +343,7 @@
 void
 writebyte_internal( libspectrum_word address, libspectrum_byte b )
 {
-  libspectrum_word bank = address >> 13;
+  libspectrum_word bank = address >> MEMORY_PAGE_SIZE_LOGARITHM;
   memory_page *mapping = &memory_map_write[ bank ];
 
   if( opus_active && address >= 0x2800 && address < 0x3800 ) {
@@ -351,7 +351,7 @@
   } else if( mapping->writable ||
              (mapping->source != memory_source_none &&
               settings_current.writable_roms) ) {
-    libspectrum_word offset = address & 0x1fff;
+    libspectrum_word offset = address & MEMORY_PAGE_SIZE_MASK;
     libspectrum_byte *memory = mapping->page;
 
     memory_display_dirty( address, b );

Modified: branches/2011-05-04-memory/fuse/memory.h
===================================================================
--- branches/2011-05-04-memory/fuse/memory.h	2011-05-04 22:41:32 UTC (rev 4421)
+++ branches/2011-05-04-memory/fuse/memory.h	2011-05-04 23:02:33 UTC (rev 4422)
@@ -63,17 +63,28 @@
 
 } memory_page;
 
-#define MEMORY_PAGE_SIZE 0x2000
+/* A memory page will be 1 << (this many) bytes in size */
+#define MEMORY_PAGE_SIZE_LOGARITHM 13
 
-/* Each 8Kb RAM chunk accessible by the Z80 */
-extern memory_page memory_map_read[8];
-extern memory_page memory_map_write[8];
+/* The actual size of a memory page */
+#define MEMORY_PAGE_SIZE ( 1 << MEMORY_PAGE_SIZE_LOGARITHM )
 
-/* 8 8Kb memory chunks accessible by the Z80 for normal RAM (home) and
+/* The mask to use to select the bits within a page */
+#define MEMORY_PAGE_SIZE_MASK ( MEMORY_PAGE_SIZE - 1 )
+
+/* The number of memory pages in 64K
+   This calculation is equivalent to 2^16 / MEMORY_PAGE_SIZE */
+#define MEMORY_PAGES_IN_64K ( 1 << ( 16 - MEMORY_PAGE_SIZE_LOGARITHM ) )
+
+/* Each RAM chunk accessible by the Z80 */
+extern memory_page memory_map_read[MEMORY_PAGES_IN_64K];
+extern memory_page memory_map_write[MEMORY_PAGES_IN_64K];
+
+/* Memory chunks accessible by the Z80 for normal RAM (home) and
    the Timex Dock and Exrom */
-extern memory_page *memory_map_home[8];
-extern memory_page *memory_map_dock[8];
-extern memory_page *memory_map_exrom[8];
+extern memory_page *memory_map_home[MEMORY_PAGES_IN_64K];
+extern memory_page *memory_map_dock[MEMORY_PAGES_IN_64K];
+extern memory_page *memory_map_exrom[MEMORY_PAGES_IN_64K];
 
 extern memory_page memory_map_ram[ 2 * SPECTRUM_RAM_PAGES ];
 extern memory_page memory_map_rom[ 8];
@@ -108,7 +119,7 @@
 #ifndef CORETEST
 
 #define readbyte_internal( address ) \
-  memory_map_read[ (libspectrum_word)(address) >> 13 ].page[ (address) & 0x1fff ]
+  memory_map_read[ (libspectrum_word)(address) >> MEMORY_PAGE_SIZE_LOGARITHM ].page[ (address) & MEMORY_PAGE_SIZE_MASK ]
 
 #else				/* #ifndef CORETEST */
 

Modified: branches/2011-05-04-memory/fuse/peripherals/ula.c
===================================================================
--- branches/2011-05-04-memory/fuse/peripherals/ula.c	2011-05-04 22:41:32 UTC (rev 4421)
+++ branches/2011-05-04-memory/fuse/peripherals/ula.c	2011-05-04 23:02:33 UTC (rev 4422)
@@ -176,7 +176,7 @@
 void
 ula_contend_port_early( libspectrum_word port )
 {
-  if( memory_map_read[ port >> 13 ].contended )
+  if( memory_map_read[ port >> MEMORY_PAGE_SIZE_LOGARITHM ].contended )
     tstates += ula_contention_no_mreq[ tstates ];
    
   tstates++;
@@ -191,7 +191,7 @@
 
   } else {
 
-    if( memory_map_read[ port >> 13 ].contended ) {
+    if( memory_map_read[ port >> MEMORY_PAGE_SIZE_LOGARITHM ].contended ) {
       tstates += ula_contention_no_mreq[ tstates ]; tstates++;
       tstates += ula_contention_no_mreq[ tstates ]; tstates++;
       tstates += ula_contention_no_mreq[ tstates ];


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