X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=pico%2F32x%2Fpwm.c;h=36261d7f973895bfb25d4bca0898c925feb812c2;hb=9c9cda8c39bd2a6b99b8420a3034c454bc713954;hp=3adbf211f39de0db98a956f6c46b1d69244e15ba;hpb=a8fd6e376175c06e2423d0914359c761829d6e93;p=picodrive.git

diff --git a/pico/32x/pwm.c b/pico/32x/pwm.c
index 3adbf21..36261d7 100644
--- a/pico/32x/pwm.c
+++ b/pico/32x/pwm.c
@@ -52,10 +52,15 @@ void p32x_timers_do(unsigned int cycles)
 
   cycles *= 3;
 
-  pwm_cycle_counter += cycles;
-  while (pwm_cycle_counter > pwm_cycles) {
-    pwm_cycle_counter -= pwm_cycles;
-    pwm_smp_expect++;
+  // 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++;
+    }
   }
 
   // WDT timers
@@ -81,21 +86,35 @@ void p32x_timers_do(unsigned int cycles)
   }
 }
 
-void p32x_pwm_schedule(unsigned int now)
+static int p32x_pwm_schedule_(void)
 {
   int tm;
 
   if (Pico32x.emu_flags & P32XF_PWM_PEND)
-    return; // already scheduled
+    return 0; // already scheduled
   if (Pico32x.sh2irqs & P32XI_PWM)
-    return; // previous not acked
+    return 0; // previous not acked
   if (!((Pico32x.sh2irq_mask[0] | Pico32x.sh2irq_mask[1]) & 1))
-    return; // masked by everyone
+    return 0; // masked by everyone
 
+  Pico32x.emu_flags |= P32XF_PWM_PEND;
   tm = (Pico32x.regs[0x30 / 2] & 0x0f00) >> 8;
   tm = ((tm - 1) & 0x0f) + 1;
-  p32x_event_schedule(P32X_EVENT_PWM, now, pwm_cycles * tm / 3);
-  Pico32x.emu_flags |= P32XF_PWM_PEND;
+  return pwm_cycles * tm / 3;
+}
+
+void p32x_pwm_schedule(unsigned int now)
+{
+  int after = p32x_pwm_schedule_();
+  if (after != 0)
+    p32x_event_schedule(now, P32X_EVENT_PWM, after);
+}
+
+void p32x_pwm_schedule_sh2(SH2 *sh2)
+{
+  int after = p32x_pwm_schedule_();
+  if (after != 0)
+    p32x_event_schedule_sh2(sh2, P32X_EVENT_PWM, after);
 }
 
 unsigned int p32x_pwm_read16(unsigned int a)