X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=pico%2Fcd%2Fmcd.c;h=0824ec0d2700da5deea04f04aa1eb7b4b3c0b1e6;hb=b26701370b773deded710187215a7db98513b941;hp=539d157e0ebffa1a35d91ead576c22a383c43145;hpb=89dbbf2b2fe885c9f443178c1f1350567e92160b;p=picodrive.git

diff --git a/pico/cd/mcd.c b/pico/cd/mcd.c
index 539d157..0824ec0 100644
--- a/pico/cd/mcd.c
+++ b/pico/cd/mcd.c
@@ -35,19 +35,22 @@ PICO_INTERNAL void PicoPowerMCD(void)
   memset(Pico_mcd->word_ram2M, 0, sizeof(Pico_mcd->word_ram2M));
   memset(Pico_mcd->pcm_ram,    0, sizeof(Pico_mcd->pcm_ram));
   memset(Pico_mcd->bram, 0, sizeof(Pico_mcd->bram));
-  memcpy(Pico_mcd->bram + sizeof(Pico_mcd->bram) - fmt_size, formatted_bram, fmt_size);
-}
-
-PICO_INTERNAL int PicoResetMCD(void)
-{
+  memcpy(Pico_mcd->bram + sizeof(Pico_mcd->bram) - fmt_size,
+    formatted_bram, fmt_size);
   memset(Pico_mcd->s68k_regs, 0, sizeof(Pico_mcd->s68k_regs));
   memset(&Pico_mcd->pcm, 0, sizeof(Pico_mcd->pcm));
   memset(&Pico_mcd->m, 0, sizeof(Pico_mcd->m));
 
-  memset(Pico_mcd->bios + 0x70, 0xff, 4); // reset hint vector (simplest way to implement reg6)
-  Pico_mcd->m.state_flags = 0;
-  Pico_mcd->s68k_regs[3] = 1; // 2M word RAM mode with m68k access after reset
+  // cold reset state (tested)
+  Pico_mcd->m.state_flags = PCD_ST_S68K_RST;
+  Pico_mcd->m.busreq = 2;     // busreq on, s68k in reset
+  Pico_mcd->s68k_regs[3] = 1; // 2M word RAM mode, m68k access
+  memset(Pico_mcd->bios + 0x70, 0xff, 4);
+}
 
+PICO_INTERNAL int PicoResetMCD(void)
+{
+  // ??
   Reset_CD();
   LC89510_Reset();
   gfx_cd_reset();
@@ -79,6 +82,9 @@ static __inline void SekRunS68k(unsigned int to)
   if ((cyc_do = SekCycleAimS68k - SekCycleCntS68k) <= 0)
     return;
 
+  if (SekShouldInterrupt())
+    Pico_mcd->m.s68k_poll_a = 0;
+
   SekCycleCntS68k += cyc_do;
 #if defined(EMU_C68K)
   PicoCpuCS68k.cycles = cyc_do;
@@ -229,7 +235,7 @@ int pcd_sync_s68k(unsigned int m68k_target, int m68k_poll_sync)
   elprintf(EL_CD, "s68k sync to %u, %u->%u",
     m68k_target, now, s68k_target);
 
-  if ((Pico_mcd->m.busreq & 3) != 1) { /* busreq/reset */
+  if (Pico_mcd->m.busreq != 1) { /* busreq/reset */
     SekCycleCntS68k = SekCycleAimS68k = s68k_target;
     pcd_run_events(m68k_target);
     return 0;
@@ -252,15 +258,20 @@ int pcd_sync_s68k(unsigned int m68k_target, int m68k_poll_sync)
   #undef now
 }
 
+#define pcd_run_cpus_normal pcd_run_cpus
+//#define pcd_run_cpus_lockstep pcd_run_cpus
+
 static void SekSyncM68k(void);
 
-static void pcd_run_cpus(int m68k_cycles)
+static inline void pcd_run_cpus_normal(int m68k_cycles)
 {
   SekCycleAim += m68k_cycles;
-  if (Pico_mcd->m.m68k_poll_cnt >= 16 && !SekShouldInterrupt()) {
+  if (SekShouldInterrupt() || Pico_mcd->m.m68k_poll_cnt < 12)
+    Pico_mcd->m.m68k_poll_cnt = 0;
+  else if (Pico_mcd->m.m68k_poll_cnt >= 16) {
     int s68k_left = pcd_sync_s68k(SekCycleAim, 1);
     if (s68k_left <= 0) {
-      elprintf(EL_CDPOLL, "m68k poll [%02x] %d @%06x",
+      elprintf(EL_CDPOLL, "m68k poll [%02x] x%d @%06x",
         Pico_mcd->m.m68k_poll_a, Pico_mcd->m.m68k_poll_cnt, SekPc);
       SekCycleCnt = SekCycleAim;
       return;
@@ -271,6 +282,18 @@ static void pcd_run_cpus(int m68k_cycles)
   SekSyncM68k();
 }
 
+static inline void pcd_run_cpus_lockstep(int m68k_cycles)
+{
+  unsigned int target = SekCycleAim + m68k_cycles;
+  do {
+    SekCycleAim += 8;
+    SekSyncM68k();
+    pcd_sync_s68k(SekCycleAim, 0);
+  } while (CYCLES_GT(target, SekCycleAim));
+
+  SekCycleAim = target;
+}
+
 #define PICO_CD
 #define CPUS_RUN(m68k_cycles) \
   pcd_run_cpus(m68k_cycles)