From d9153729685381acb0559d8a4fdca47cb839427a Mon Sep 17 00:00:00 2001
From: notaz <notasas@gmail.com>
Date: Sat, 31 Mar 2007 17:25:48 +0000
Subject: [PATCH] z80 timing change

git-svn-id: file:///home/notaz/opt/svn/PicoDrive@84 be3aeb3a-fb24-0410-a615-afba39da0efa
---
 Pico/Memory.c         |  5 +----
 Pico/MemoryCmn.c      | 13 +++++++++----
 Pico/Pico.c           | 15 +++++++++++----
 Pico/PicoInt.h        |  1 +
 Pico/cd/Pico.c        | 11 +++++++++--
 cpu/musashi/m68kcpu.c |  2 +-
 6 files changed, 32 insertions(+), 15 deletions(-)

diff --git a/Pico/Memory.c b/Pico/Memory.c
index 3157a63..32b25ca 100644
--- a/Pico/Memory.c
+++ b/Pico/Memory.c
@@ -392,10 +392,7 @@ static void CPU_CALL PicoWrite8(u32 a,u8 d)
   //if ((a&0xe0ffff)==0xe0a9ba+0x69c)
   //  dprintf("w8 : %06x,   %02x @%06x", a&0xffffff, d, SekPc);
 
-
-  if ((a&0xe00000)==0xe00000) {
-	  if((a&0xffff)==0xf62a) dprintf("(f62a) = %02x [%i|%i] @ %x", d, Pico.m.scanline, SekCyclesDone(), SekPc);
-	   u8 *pm=(u8 *)(Pico.ram+((a^1)&0xffff)); pm[0]=d; return; } // Ram
+  if ((a&0xe00000)==0xe00000) { *(u8 *)(Pico.ram+((a^1)&0xffff))=d; return; } // Ram
 
   a&=0xffffff;
   OtherWrite8(a,d,8);
diff --git a/Pico/MemoryCmn.c b/Pico/MemoryCmn.c
index 02d45d8..48c564c 100644
--- a/Pico/MemoryCmn.c
+++ b/Pico/MemoryCmn.c
@@ -149,16 +149,21 @@ void OtherWrite8(u32 a,u32 d,int realsize)
     return;
   }
   if (a==0xa11100) {
-    extern int z80startCycle, z80stopCycle;
     //int lineCycles=(488-SekCyclesLeft)&0x1ff;
     d&=1; d^=1;
     if(!d) {
       // this is for a nasty situation where Z80 was enabled and disabled in the same 68k timeslice (Golden Axe III)
       if (Pico.m.z80Run) {
-        int lineCycles=(488-SekCyclesLeft)&0x1ff;
+        int lineCycles;
         z80stopCycle = SekCyclesDone();
-        lineCycles=(lineCycles>>1)-(lineCycles>>5);
-        z80_run(lineCycles);
+        if (Pico.m.z80Run&2)
+             lineCycles=(488-SekCyclesLeft)&0x1ff;
+        else lineCycles=z80stopCycle-z80startCycle; // z80 was started at current line
+        if (lineCycles > 0 && lineCycles <= 488) {
+          dprintf("zrun: %i/%i cycles", lineCycles, (lineCycles>>1)-(lineCycles>>5));
+          lineCycles=(lineCycles>>1)-(lineCycles>>5);
+          z80_run(lineCycles);
+        }
       }
     } else {
       z80startCycle = SekCyclesDone();
diff --git a/Pico/Pico.c b/Pico/Pico.c
index d0845e1..04a0b97 100644
--- a/Pico/Pico.c
+++ b/Pico/Pico.c
@@ -430,11 +430,18 @@ static int PicoFrameHints(void)
       getSamples(y);
 
     // Run scanline:
-    if(Pico.m.dma_bytes) SekCycleCnt+=CheckDMA();
+    if (Pico.m.dma_bytes) SekCycleCnt+=CheckDMA();
     SekRun(cycles_68k);
-    if((PicoOpt&4) && Pico.m.z80Run) {
-      Pico.m.z80Run|=2;
-      z80CycleAim+=cycles_z80;
+    if ((PicoOpt&4) && Pico.m.z80Run) {
+      if (Pico.m.z80Run & 2) z80CycleAim+=cycles_z80;
+      else {
+        int cnt = SekCyclesDone() - z80startCycle;
+        cnt = (cnt>>1)-(cnt>>5);
+        //if (cnt > cycles_z80) printf("FIXME: z80 cycles: %i\n", cnt);
+        if (cnt > cycles_z80) cnt = cycles_z80;
+        Pico.m.z80Run |= 2;
+        z80CycleAim+=cnt;
+      }
       total_z80+=z80_run(z80CycleAim-total_z80);
     }
   }
diff --git a/Pico/PicoInt.h b/Pico/PicoInt.h
index e11f58b..2b802d7 100644
--- a/Pico/PicoInt.h
+++ b/Pico/PicoInt.h
@@ -299,6 +299,7 @@ void PicoWriteCD32(unsigned int a, unsigned int d);
 extern struct Pico Pico;
 extern struct PicoSRAM SRam;
 extern int emustatus;
+extern int z80startCycle, z80stopCycle; // in 68k cycles
 int CheckDMA(void);
 
 // cd/Pico.c
diff --git a/Pico/cd/Pico.c b/Pico/cd/Pico.c
index 00be7b6..0759acb 100644
--- a/Pico/cd/Pico.c
+++ b/Pico/cd/Pico.c
@@ -331,8 +331,15 @@ static int PicoFrameHintsMCD(void)
     }
 
     if ((PicoOpt&4) && Pico.m.z80Run) {
-      Pico.m.z80Run|=2;
-      z80CycleAim+=cycles_z80;
+      if (Pico.m.z80Run & 2) z80CycleAim+=cycles_z80;
+      else {
+        int cnt = SekCyclesDone() - z80startCycle;
+        cnt = (cnt>>1)-(cnt>>5);
+        //if (cnt > cycles_z80) printf("FIXME: z80 cycles: %i\n", cnt);
+        if (cnt > cycles_z80) cnt = cycles_z80;
+        Pico.m.z80Run |= 2;
+        z80CycleAim+=cnt;
+      }
       total_z80+=z80_run(z80CycleAim-total_z80);
     }
 
diff --git a/cpu/musashi/m68kcpu.c b/cpu/musashi/m68kcpu.c
index e4212a8..14a6cad 100644
--- a/cpu/musashi/m68kcpu.c
+++ b/cpu/musashi/m68kcpu.c
@@ -788,7 +788,7 @@ int m68k_execute(int num_cycles)
 		m68ki_set_address_error_trap(); /* auto-disable (see m68kcpu.h) */
 
 		/* Main loop.  Keep going until we run out of clock cycles */
-		while(GET_CYCLES() > 0)
+		while(GET_CYCLES() >= 0)
 		{
 			/* Set tracing accodring to T1. (T0 is done inside instruction) */
 			m68ki_trace_t1(); /* auto-disable (see m68kcpu.h) */
-- 
2.39.2