[Core/MD] reduced savestate size when both Mega CD and MegaSD hardwar…

…e are detected (fixes savestates with MSU-MD games that have "SEGA MEGASD" in ROM header)
2play · Aug 31, 2022 · eef172a · eef172a
1 parent 47d2026
commit eef172a
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Showing 5 changed files with 25 additions and 16 deletions.
diff --git a/builds/genesis_plus_gx_libretro.dll b/builds/genesis_plus_gx_libretro.dll
diff --git a/builds/genplus_cube.dol b/builds/genplus_cube.dol
diff --git a/builds/genplus_wii.dol b/builds/genplus_wii.dol
diff --git a/core/cart_hw/megasd.c b/core/cart_hw/megasd.c
@@ -2,7 +2,7 @@
  *  Genesis Plus
  *  MegaSD flashcart CD hardware interface overlay & enhanced ROM mappers
  *
- *  Copyright (C) 2020-2021 Eke-Eke (Genesis Plus GX)
+ *  Copyright (C) 2020-2022 Eke-Eke (Genesis Plus GX)
  *
  *  Redistribution and use of this code or any derivative works are permitted
  *  provided that the following conditions are met:
@@ -91,20 +91,28 @@ void megasd_reset(void)
   m68k.memory_map[0x03].write16 = megasd_ctrl_write_word;
   zbank_memory_map[0x03].read   = megasd_ctrl_read_byte;
 
-  /* reset CD hardware */
-  pcm_reset();
-  cdd_reset();
-  scd.regs[0x36>>1].byte.h = 0x01;
+  /* reset CD hardware (only if not already emulated) */
+  if (system_hw != SYSTEM_MCD)
+  {
+    pcm_reset();
+    cdd_reset();
+    scd.regs[0x36>>1].byte.h = 0x01;
+  }
 }
 
 int megasd_context_save(uint8 *state)
 {
   int bufferptr = 0;
 
   save_param(&megasd_hw, sizeof(megasd_hw));
-  bufferptr += cdd_context_save(&state[bufferptr]);
-  bufferptr += pcm_context_save(&state[bufferptr]);
-  save_param(&scd.regs[0x36>>1].byte.h, 1);
+
+  /* save needed CD hardware state (only if not already saved) */
+  if (system_hw != SYSTEM_MCD)
+  {
+    bufferptr += cdd_context_save(&state[bufferptr]);
+    bufferptr += pcm_context_save(&state[bufferptr]);
+    save_param(&scd.regs[0x36>>1].byte.h, 1);
+  }
 
   return bufferptr;
 }
@@ -114,9 +122,14 @@ int megasd_context_load(uint8 *state)
   int bufferptr = 0;
 
   load_param(&megasd_hw, sizeof(megasd_hw));
-  bufferptr += cdd_context_load(&state[bufferptr], STATE_VERSION);
-  bufferptr += pcm_context_load(&state[bufferptr]);
-  load_param(&scd.regs[0x36>>1].byte.h, 1);
+
+  /* load needed CD hardware state (only if not already loaded) */
+  if (system_hw != SYSTEM_MCD)
+  {
+    bufferptr += cdd_context_load(&state[bufferptr], STATE_VERSION);
+    bufferptr += pcm_context_load(&state[bufferptr]);
+    load_param(&scd.regs[0x36>>1].byte.h, 1);
+  }
 
   return bufferptr;
 }
@@ -314,10 +327,6 @@ void megasd_rom_mapper_w(unsigned int address, unsigned int data)
         m68k.memory_map[i].write16  = m68k_unused_16_w;
         zbank_memory_map[i].write   = zbank_unused_w;
       }
-
-      /* enable CD hardware overlay access */
-      m68k.memory_map[0x03].write8 = megasd_ctrl_write_byte;
-      m68k.memory_map[0x03].write16 = megasd_ctrl_write_word;
     }
   }
   else

diff --git a/core/cart_hw/megasd.h b/core/cart_hw/megasd.h
@@ -2,7 +2,7 @@
  *  Genesis Plus
  *  MegaSD flashcart CD hardware interface overlay & enhanced ROM mappers
  *
- *  Copyright (C) 2020-2021  Eke-Eke (Genesis Plus GX)
+ *  Copyright (C) 2020-2022  Eke-Eke (Genesis Plus GX)
  *
  *  Redistribution and use of this code or any derivative works are permitted
  *  provided that the following conditions are met: