X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=pico%2F32x%2Fpwm.c;h=6f9cd07eedd99eac7b4cef51d9d1a5c42cf61d8d;hb=8ce9c3a782e47ed355a12789859e5359c4a81e77;hp=36261d7f973895bfb25d4bca0898c925feb812c2;hpb=19886062f1a36f70b1f01d58f3fa1b79162defac;p=picodrive.git

diff --git a/pico/32x/pwm.c b/pico/32x/pwm.c
index 36261d7..6f9cd07 100644
--- a/pico/32x/pwm.c
+++ b/pico/32x/pwm.c
@@ -1,177 +1,241 @@
 /*
  * PicoDrive
- * (C) notaz, 2009,2010
+ * (C) notaz, 2009,2010,2013
  *
  * This work is licensed under the terms of MAME license.
  * See COPYING file in the top-level directory.
  */
 #include "../pico_int.h"
 
-static int pwm_cycle_counter;
 static int pwm_cycles;
 static int pwm_mult;
 static int pwm_ptr;
+static int pwm_irq_reload;
+static int pwm_doing_fifo;
+static int pwm_silent;
 
-static int pwm_smp_cnt;
-static int pwm_smp_expect;
-
-static int timer_cycles[2];
-static int timer_tick_cycles[2];
-
-// timers. This includes PWM timer in 32x and internal SH2 timers
-void p32x_timers_recalc(void)
+void p32x_pwm_ctl_changed(void)
 {
+  int control = Pico32x.regs[0x30 / 2];
   int cycles = Pico32x.regs[0x32 / 2];
-  int tmp, i;
 
   cycles = (cycles - 1) & 0x0fff;
-  if (cycles < 500) {
-    elprintf(EL_32X|EL_PWM|EL_ANOMALY, "pwm: low cycle value: %d", cycles + 1);
-    cycles = 500;
-  }
   pwm_cycles = cycles;
-  pwm_mult = 0x10000 / cycles;
-
-  // SH2 timer step
-  for (i = 0; i < 2; i++) {
-    tmp = PREG8(Pico32xMem->sh2_peri_regs[i], 0x80) & 7;
-    // Sclk cycles per timer tick
-    if (tmp)
-      cycles = 0x20 << tmp;
-    else
-      cycles = 2;
-    timer_tick_cycles[i] = cycles;
-    elprintf(EL_32X, "WDT cycles[%d] = %d", i, cycles);
+
+  // supposedly we should stop FIFO when xMd is 0,
+  // but mars test disagrees
+  pwm_mult = 0;
+  if ((control & 0x0f) != 0)
+    pwm_mult = 0x10000 / cycles;
+
+  pwm_irq_reload = (control & 0x0f00) >> 8;
+  pwm_irq_reload = ((pwm_irq_reload - 1) & 0x0f) + 1;
+
+  if (Pico32x.pwm_irq_cnt == 0)
+    Pico32x.pwm_irq_cnt = pwm_irq_reload;
+}
+
+static void do_pwm_irq(SH2 *sh2, unsigned int m68k_cycles)
+{
+  p32x_trigger_irq(sh2, m68k_cycles, P32XI_PWM);
+
+  if (Pico32x.regs[0x30 / 2] & P32XP_RTP) {
+    p32x_event_schedule(m68k_cycles, P32X_EVENT_PWM, pwm_cycles / 3 + 1);
+    // note: might recurse
+    p32x_dreq1_trigger();
   }
 }
 
-// PWM irq for every tm samples
-void p32x_timers_do(unsigned int cycles)
+static int convert_sample(unsigned int v)
+{
+  if (v == 0)
+    return 0;
+  if (v > pwm_cycles)
+    v = pwm_cycles;
+  return ((int)v - pwm_cycles / 2) * pwm_mult;
+}
+
+#define consume_fifo(sh2, m68k_cycles) { \
+  int cycles_diff = ((m68k_cycles) * 3) - Pico32x.pwm_cycle_p; \
+  if (cycles_diff >= pwm_cycles) \
+    consume_fifo_do(sh2, m68k_cycles, cycles_diff); \
+}
+
+static void consume_fifo_do(SH2 *sh2, unsigned int m68k_cycles,
+  int sh2_cycles_diff)
 {
-  int cnt, i;
-
-  cycles *= 3;
-
-  // since we run things in async fashion, allow pwm to lag behind
-  // but don't allow our "queue" to be infinite
-  cnt = pwm_smp_expect - pwm_smp_cnt;
-  if (cnt <= 0 || cnt * pwm_cycles < OSC_NTSC/7*3 / 60 / 2) {
-    pwm_cycle_counter += cycles;
-    while (pwm_cycle_counter > pwm_cycles) {
-      pwm_cycle_counter -= pwm_cycles;
-      pwm_smp_expect++;
+  struct Pico32xMem *mem = Pico32xMem;
+  unsigned short *fifo_l = mem->pwm_fifo[0];
+  unsigned short *fifo_r = mem->pwm_fifo[1];
+  int sum = 0;
+
+  if (pwm_cycles == 0 || pwm_doing_fifo)
+    return;
+
+  elprintf(EL_PWM, "pwm: %u: consume %d/%d, %d,%d ptr %d",
+    m68k_cycles, sh2_cycles_diff, sh2_cycles_diff / pwm_cycles,
+    Pico32x.pwm_p[0], Pico32x.pwm_p[1], pwm_ptr);
+
+  // this is for recursion from dreq1 writes
+  pwm_doing_fifo = 1;
+
+  for (; sh2_cycles_diff >= pwm_cycles; sh2_cycles_diff -= pwm_cycles)
+  {
+    if (Pico32x.pwm_p[0] > 0) {
+      fifo_l[0] = fifo_l[1];
+      fifo_l[1] = fifo_l[2];
+      fifo_l[2] = fifo_l[3];
+      Pico32x.pwm_p[0]--;
+      mem->pwm_current[0] = convert_sample(fifo_l[0]);
+      sum += mem->pwm_current[0];
+    }
+    if (Pico32x.pwm_p[1] > 0) {
+      fifo_r[0] = fifo_r[1];
+      fifo_r[1] = fifo_r[2];
+      fifo_r[2] = fifo_r[3];
+      Pico32x.pwm_p[1]--;
+      mem->pwm_current[1] = convert_sample(fifo_r[0]);
+      sum += mem->pwm_current[1];
     }
-  }
 
-  // WDT timers
-  for (i = 0; i < 2; i++) {
-    void *pregs = Pico32xMem->sh2_peri_regs[i];
-    if (PREG8(pregs, 0x80) & 0x20) { // TME
-      timer_cycles[i] += cycles;
-      cnt = PREG8(pregs, 0x81);
-      while (timer_cycles[i] >= timer_tick_cycles[i]) {
-        timer_cycles[i] -= timer_tick_cycles[i];
-        cnt++;
-      }
-      if (cnt >= 0x100) {
-        int level = PREG8(pregs, 0xe3) >> 4;
-        int vector = PREG8(pregs, 0xe4) & 0x7f;
-        elprintf(EL_32X, "%csh2 WDT irq (%d, %d)",
-          i ? 's' : 'm', level, vector);
-        sh2_internal_irq(&sh2s[i], level, vector);
-        cnt &= 0xff;
-      }
-      PREG8(pregs, 0x81) = cnt;
+    mem->pwm[pwm_ptr * 2    ] = mem->pwm_current[0];
+    mem->pwm[pwm_ptr * 2 + 1] = mem->pwm_current[1];
+    pwm_ptr = (pwm_ptr + 1) & (PWM_BUFF_LEN - 1);
+
+    if (--Pico32x.pwm_irq_cnt == 0) {
+      Pico32x.pwm_irq_cnt = pwm_irq_reload;
+      do_pwm_irq(sh2, m68k_cycles);
     }
   }
+  Pico32x.pwm_cycle_p = m68k_cycles * 3 - sh2_cycles_diff;
+  pwm_doing_fifo = 0;
+  if (sum != 0)
+    pwm_silent = 0;
 }
 
-static int p32x_pwm_schedule_(void)
+static int p32x_pwm_schedule_(SH2 *sh2, unsigned int m68k_now)
 {
-  int tm;
+  unsigned int sh2_now = m68k_now * 3;
+  int cycles_diff_sh2;
+
+  if (pwm_cycles == 0)
+    return 0;
+
+  cycles_diff_sh2 = sh2_now - Pico32x.pwm_cycle_p;
+  if (cycles_diff_sh2 >= pwm_cycles)
+    consume_fifo_do(sh2, m68k_now, cycles_diff_sh2);
 
-  if (Pico32x.emu_flags & P32XF_PWM_PEND)
-    return 0; // already scheduled
-  if (Pico32x.sh2irqs & P32XI_PWM)
-    return 0; // previous not acked
   if (!((Pico32x.sh2irq_mask[0] | Pico32x.sh2irq_mask[1]) & 1))
     return 0; // masked by everyone
 
-  Pico32x.emu_flags |= P32XF_PWM_PEND;
-  tm = (Pico32x.regs[0x30 / 2] & 0x0f00) >> 8;
-  tm = ((tm - 1) & 0x0f) + 1;
-  return pwm_cycles * tm / 3;
+  cycles_diff_sh2 = sh2_now - Pico32x.pwm_cycle_p;
+  return (Pico32x.pwm_irq_cnt * pwm_cycles
+           - cycles_diff_sh2) / 3 + 1;
 }
 
-void p32x_pwm_schedule(unsigned int now)
+void p32x_pwm_schedule(unsigned int m68k_now)
 {
-  int after = p32x_pwm_schedule_();
+  int after = p32x_pwm_schedule_(NULL, m68k_now);
   if (after != 0)
-    p32x_event_schedule(now, P32X_EVENT_PWM, after);
+    p32x_event_schedule(m68k_now, P32X_EVENT_PWM, after);
 }
 
 void p32x_pwm_schedule_sh2(SH2 *sh2)
 {
-  int after = p32x_pwm_schedule_();
+  int after = p32x_pwm_schedule_(sh2, sh2_cycles_done_m68k(sh2));
   if (after != 0)
     p32x_event_schedule_sh2(sh2, P32X_EVENT_PWM, after);
 }
 
-unsigned int p32x_pwm_read16(unsigned int a)
+void p32x_pwm_sync_to_sh2(SH2 *sh2)
+{
+  int m68k_cycles = sh2_cycles_done_m68k(sh2);
+  consume_fifo(sh2, m68k_cycles);
+}
+
+void p32x_pwm_irq_event(unsigned int m68k_now)
+{
+  p32x_pwm_schedule(m68k_now);
+}
+
+unsigned int p32x_pwm_read16(unsigned int a, SH2 *sh2,
+  unsigned int m68k_cycles)
 {
   unsigned int d = 0;
-  int diff;
+
+  consume_fifo(sh2, m68k_cycles);
 
   a &= 0x0e;
   switch (a) {
     case 0: // control
     case 2: // cycle
-      return Pico32x.regs[(0x30 + a) / 2];
+      d = Pico32x.regs[(0x30 + a) / 2];
+      break;
 
     case 4: // L ch
+      if (Pico32x.pwm_p[0] == 3)
+        d |= P32XP_FULL;
+      else if (Pico32x.pwm_p[0] == 0)
+        d |= P32XP_EMPTY;
+      break;
+
     case 6: // R ch
     case 8: // MONO
-      diff = pwm_smp_cnt - pwm_smp_expect;
-      elprintf(EL_PWM, "pwm: read status: ptr %d/%d %d",
-        pwm_smp_cnt, pwm_smp_expect, diff);
-      if (diff > 3)
+      if (Pico32x.pwm_p[1] == 3)
         d |= P32XP_FULL;
-      else if (diff < 0)
+      else if (Pico32x.pwm_p[1] == 0)
         d |= P32XP_EMPTY;
       break;
   }
 
+  elprintf(EL_PWM, "pwm: %u: r16 %02x %04x (p %d %d)",
+    m68k_cycles, a, d, Pico32x.pwm_p[0], Pico32x.pwm_p[1]);
   return d;
 }
 
-void p32x_pwm_write16(unsigned int a, unsigned int d)
+void p32x_pwm_write16(unsigned int a, unsigned int d,
+  SH2 *sh2, unsigned int m68k_cycles)
 {
+  elprintf(EL_PWM, "pwm: %u: w16 %02x %04x (p %d %d)",
+    m68k_cycles, a & 0x0e, d, Pico32x.pwm_p[0], Pico32x.pwm_p[1]);
+
+  consume_fifo(sh2, m68k_cycles);
+
   a &= 0x0e;
-  if (a == 0) // control
+  if (a == 0) { // control
+    // avoiding pops..
+    if ((Pico32x.regs[0x30 / 2] & 0x0f) == 0)
+      Pico32xMem->pwm_fifo[0][0] = Pico32xMem->pwm_fifo[1][0] = 0;
     Pico32x.regs[0x30 / 2] = d;
+    p32x_pwm_ctl_changed();
+    Pico32x.pwm_irq_cnt = pwm_irq_reload; // ?
+  }
   else if (a == 2) { // cycle
     Pico32x.regs[0x32 / 2] = d & 0x0fff;
-    p32x_timers_recalc();
-    Pico32x.pwm_irq_sample_cnt = 0; // resets?
+    p32x_pwm_ctl_changed();
   }
   else if (a <= 8) {
-    d &= 0x0fff;
-    if (d > pwm_cycles)
-      d = pwm_cycles;
-    d = (d - pwm_cycles / 2) * pwm_mult;
-
-    if       (a < 6) // L ch
-      Pico32xMem->pwm[pwm_ptr * 2] = d;
-    else if (a == 6) // R ch
-      Pico32xMem->pwm[pwm_ptr * 2 + 1] = d;
-    else             // MONO
-      Pico32xMem->pwm[pwm_ptr * 2] = Pico32xMem->pwm[pwm_ptr * 2 + 1] = d;
-
-    if (a >= 6) { // R or MONO
-      pwm_smp_cnt++;
-      pwm_ptr = (pwm_ptr + 1) & (PWM_BUFF_LEN - 1);
-      elprintf(EL_PWM, "pwm: smp_cnt %d, ptr %d, smp %x",
-          pwm_smp_cnt, pwm_ptr, d);
+    d = (d - 1) & 0x0fff;
+
+    if (a == 4 || a == 8) { // L ch or MONO
+      unsigned short *fifo = Pico32xMem->pwm_fifo[0];
+      if (Pico32x.pwm_p[0] < 3)
+        Pico32x.pwm_p[0]++;
+      else {
+        fifo[1] = fifo[2];
+        fifo[2] = fifo[3];
+      }
+      fifo[Pico32x.pwm_p[0]] = d;
+    }
+    if (a == 6 || a == 8) { // R ch or MONO
+      unsigned short *fifo = Pico32xMem->pwm_fifo[1];
+      if (Pico32x.pwm_p[1] < 3)
+        Pico32x.pwm_p[1]++;
+      else {
+        fifo[1] = fifo[2];
+        fifo[2] = fifo[3];
+      }
+      fifo[Pico32x.pwm_p[1]] = d;
     }
   }
 }
@@ -181,26 +245,62 @@ void p32x_pwm_update(int *buf32, int length, int stereo)
   short *pwmb;
   int step;
   int p = 0;
+  int xmd;
+
+  consume_fifo(NULL, SekCyclesDoneT2());
 
-  if (pwm_ptr <= 16) // at least some samples..
+  xmd = Pico32x.regs[0x30 / 2] & 0x0f;
+  if (xmd == 0 || xmd == 0x06 || xmd == 0x09 || xmd == 0x0f)
+    goto out; // invalid?
+  if (pwm_silent)
     return;
 
-  step = (pwm_ptr << 16) / length; // FIXME: division..
+  step = (pwm_ptr << 16) / length;
   pwmb = Pico32xMem->pwm;
 
   if (stereo)
   {
-    while (length-- > 0) {
-      *buf32++ += pwmb[0];
-      *buf32++ += pwmb[1];
+    if (xmd == 0x05) {
+      // normal
+      while (length-- > 0) {
+        *buf32++ += pwmb[0];
+        *buf32++ += pwmb[1];
 
-      p += step;
-      pwmb += (p >> 16) * 2;
-      p &= 0xffff;
+        p += step;
+        pwmb += (p >> 16) * 2;
+        p &= 0xffff;
+      }
+    }
+    else if (xmd == 0x0a) {
+      // channel swap
+      while (length-- > 0) {
+        *buf32++ += pwmb[1];
+        *buf32++ += pwmb[0];
+
+        p += step;
+        pwmb += (p >> 16) * 2;
+        p &= 0xffff;
+      }
+    }
+    else {
+      // mono - LMD, RMD specify dst
+      if (xmd & 0x06) // src is R
+        pwmb++;
+      if (xmd & 0x0c) // dst is R
+        buf32++;
+      while (length-- > 0) {
+        *buf32 += *pwmb;
+
+        p += step;
+        pwmb += (p >> 16) * 2;
+        p &= 0xffff;
+        buf32 += 2;
+      }
     }
   }
   else
   {
+    // mostly unused
     while (length-- > 0) {
       *buf32++ += pwmb[0];
 
@@ -213,7 +313,25 @@ void p32x_pwm_update(int *buf32, int length, int stereo)
   elprintf(EL_PWM, "pwm_update: pwm_ptr %d, len %d, step %04x, done %d",
     pwm_ptr, length, step, (pwmb - Pico32xMem->pwm) / 2);
 
+out:
   pwm_ptr = 0;
+  pwm_silent = Pico32xMem->pwm_current[0] == 0
+    && Pico32xMem->pwm_current[1] == 0;
+}
+
+void p32x_pwm_state_loaded(void)
+{
+  int cycles_diff_sh2;
+
+  p32x_pwm_ctl_changed();
+
+  // for old savestates
+  cycles_diff_sh2 = SekCycleCntT * 3 - Pico32x.pwm_cycle_p;
+  if (cycles_diff_sh2 >= pwm_cycles || cycles_diff_sh2 < 0) {
+    Pico32x.pwm_irq_cnt = pwm_irq_reload;
+    Pico32x.pwm_cycle_p = SekCycleCntT * 3;
+    p32x_pwm_schedule(SekCycleCntT);
+  }
 }
 
 // vim:shiftwidth=2:ts=2:expandtab