spu: threaded implementation
[pcsx_rearmed.git] / plugins / dfsound / spu.c
index b866cff..b091efc 100644 (file)
@@ -5,7 +5,7 @@
     copyright            : (C) 2002 by Pete Bernert
     email                : BlackDove@addcom.de
 
- Portions (C) Gražvydas "notaz" Ignotas, 2010-2011
+ Portions (C) Gražvydas "notaz" Ignotas, 2010-2012,2014,2015
 
  ***************************************************************************/
 /***************************************************************************
  *                                                                         *
  ***************************************************************************/
 
+#ifndef _WIN32
+#include <sys/time.h> // gettimeofday in xa.c
+#define THREAD_ENABLED 1
+#endif
 #include "stdafx.h"
 
 #define _IN_SPU
 
 #include "externals.h"
 #include "registers.h"
-#include "cfg.h"
-#include "dsoundoss.h"
-#include "regs.h"
-
-#ifdef ENABLE_NLS
-#include <libintl.h>
-#include <locale.h>
-#define _(x)  gettext(x)
-#define N_(x) (x)
-#else
-#define _(x)  (x)
-#define N_(x) (x)
-#endif
+#include "out.h"
+#include "arm_features.h"
+#include "spu_config.h"
 
-#ifdef __arm__
+#ifdef __ARM_ARCH_7A__
  #define ssat32_to_16(v) \
   asm("ssat %0,#16,%1" : "=r" (v) : "r" (v))
 #else
  } while (0)
 #endif
 
+#define PSXCLK 33868800        /* 33.8688 MHz */
+
+// intended to be ~1 frame
+#define IRQ_NEAR_BLOCKS 32
+
 /*
 #if defined (USEMACOSX)
 static char * libraryName     = N_("Mac OS X Sound");
@@ -68,53 +67,51 @@ static char * libraryInfo     = N_("P.E.Op.S. Sound Driver V1.7\nCoded by Pete B
 
 // globals
 
-// psx buffer / addresses
-
-unsigned short  regArea[10000];
-unsigned short  spuMem[256*1024];
-unsigned char * spuMemC;
-unsigned char * pSpuIrq=0;
-unsigned char * pSpuBuffer;
-unsigned char * pMixIrq=0;
-
-// user settings
-
-int             iVolume=768; // 1024 is 1.0
-int             iXAPitch=1;
-int             iUseTimer=2;
-int             iSPUIRQWait=1;
-int             iDebugMode=0;
-int             iRecordMode=0;
-int             iUseReverb=2;
-int             iUseInterpolation=2;
+SPUInfo         spu;
+SPUConfig       spu_config;
 
 // MAIN infos struct for each channel
 
 SPUCHAN         s_chan[MAXCHAN+1];                     // channel + 1 infos (1 is security for fmod handling)
 REVERBInfo      rvb;
 
-unsigned int    dwNoiseVal;                            // global noise generator
-unsigned int    dwNoiseCount;
-int             iSpuAsyncWait=0;
-
-unsigned short  spuCtrl=0;                             // some vars to store psx reg infos
-unsigned short  spuStat=0;
-unsigned short  spuIrq=0;
-unsigned long   spuAddr=0xffffffff;                    // address into spu mem
-int             bEndThread=0;                          // thread handlers
-int             bThreadEnded=0;
-int             bSpuInit=0;
-int             bSPUIsOpen=0;
-
-static pthread_t thread = (pthread_t)-1;               // thread id (linux)
+#ifdef THREAD_ENABLED
+
+#include <pthread.h>
+#include <semaphore.h>
+#include <unistd.h>
+
+// worker thread state
+static struct {
+ unsigned int pending:1;
+ unsigned int exit_thread:1;
+ int ns_to;
+ int ctrl;
+ int decode_pos;
+ int silentch;
+ int *sRVBStart;
+ unsigned char *ram;
+ unsigned int chmask;
+ unsigned int r_chan_end;
+ unsigned int r_decode_dirty;
+ pthread_t thread;
+ sem_t sem_avail;
+ sem_t sem_done;
+ struct {
+  int spos;
+  int sbpos;
+  int sinc;
+  int start;
+  int loop;
+  int ns_to;
+  ADSRInfoEx adsr;
+  // might want to add vol and fmod flags..
+ } ch[24];
+} *worker;
 
-unsigned int dwNewChannel=0;                           // flags for faster testing, if new channel starts
-unsigned int dwChannelOn=0;                            // not silent channels
-unsigned int dwPendingChanOff=0;
-unsigned int dwChannelDead=0;                          // silent+not useful channels
-
-void (CALLBACK *irqCallback)(void)=0;                  // func of main emu, called on spu irq
-void (CALLBACK *cddavCallback)(unsigned short,unsigned short)=0;
+#else
+static const void * const worker = NULL;
+#endif
 
 // certain globals (were local before, but with the new timeproc I need em global)
 
@@ -123,15 +120,11 @@ static const int f[8][2] = {   {    0,  0  },
                         {  115, -52 },
                         {   98, -55 },
                         {  122, -60 } };
-int ChanBuf[NSSIZE+3];
-int SSumLR[(NSSIZE+3)*2];
+int ChanBuf[NSSIZE];
+int SSumLR[NSSIZE*2];
 int iFMod[NSSIZE];
-int iCycle = 0;
-short * pS;
 
-int lastch=-1;             // last channel processed on spu irq in timer mode
-static int lastns=0;       // last ns pos
-static int iSecureStart=0; // secure start counter
+#define CDDA_BUFFER_SIZE (16384 * sizeof(uint32_t)) // must be power of 2
 
 ////////////////////////////////////////////////////////////////////////
 // CODE AREA
@@ -184,70 +177,70 @@ static int iSecureStart=0; // secure start counter
 //          /
 //
 
-
-INLINE void InterpolateUp(int ch)
+static void InterpolateUp(int *SB, int sinc)
 {
- if(s_chan[ch].SB[32]==1)                              // flag == 1? calc step and set flag... and don't change the value in this pass
+ if(SB[32]==1)                                         // flag == 1? calc step and set flag... and don't change the value in this pass
   {
-   const int id1=s_chan[ch].SB[30]-s_chan[ch].SB[29];  // curr delta to next val
-   const int id2=s_chan[ch].SB[31]-s_chan[ch].SB[30];  // and next delta to next-next val :)
+   const int id1=SB[30]-SB[29];                        // curr delta to next val
+   const int id2=SB[31]-SB[30];                        // and next delta to next-next val :)
 
-   s_chan[ch].SB[32]=0;
+   SB[32]=0;
 
    if(id1>0)                                           // curr delta positive
     {
      if(id2<id1)
-      {s_chan[ch].SB[28]=id1;s_chan[ch].SB[32]=2;}
+      {SB[28]=id1;SB[32]=2;}
      else
      if(id2<(id1<<1))
-      s_chan[ch].SB[28]=(id1*s_chan[ch].sinc)/0x10000L;
+      SB[28]=(id1*sinc)>>16;
      else
-      s_chan[ch].SB[28]=(id1*s_chan[ch].sinc)/0x20000L; 
+      SB[28]=(id1*sinc)>>17;
     }
    else                                                // curr delta negative
     {
      if(id2>id1)
-      {s_chan[ch].SB[28]=id1;s_chan[ch].SB[32]=2;}
+      {SB[28]=id1;SB[32]=2;}
      else
      if(id2>(id1<<1))
-      s_chan[ch].SB[28]=(id1*s_chan[ch].sinc)/0x10000L;
+      SB[28]=(id1*sinc)>>16;
      else
-      s_chan[ch].SB[28]=(id1*s_chan[ch].sinc)/0x20000L; 
+      SB[28]=(id1*sinc)>>17;
     }
   }
  else
- if(s_chan[ch].SB[32]==2)                              // flag 1: calc step and set flag... and don't change the value in this pass
+ if(SB[32]==2)                                         // flag 1: calc step and set flag... and don't change the value in this pass
   {
-   s_chan[ch].SB[32]=0;
+   SB[32]=0;
 
-   s_chan[ch].SB[28]=(s_chan[ch].SB[28]*s_chan[ch].sinc)/0x20000L;
-   if(s_chan[ch].sinc<=0x8000)
-        s_chan[ch].SB[29]=s_chan[ch].SB[30]-(s_chan[ch].SB[28]*((0x10000/s_chan[ch].sinc)-1));
-   else s_chan[ch].SB[29]+=s_chan[ch].SB[28];
+   SB[28]=(SB[28]*sinc)>>17;
+   //if(sinc<=0x8000)
+   //     SB[29]=SB[30]-(SB[28]*((0x10000/sinc)-1));
+   //else
+   SB[29]+=SB[28];
   }
  else                                                  // no flags? add bigger val (if possible), calc smaller step, set flag1
-  s_chan[ch].SB[29]+=s_chan[ch].SB[28];
+  SB[29]+=SB[28];
 }
 
 //
 // even easier interpolation on downsampling, also no special filter, again just "Pete's common sense" tm
 //
 
-INLINE void InterpolateDown(int ch)
+static void InterpolateDown(int *SB, int sinc)
 {
- if(s_chan[ch].sinc>=0x20000L)                                 // we would skip at least one val?
+ if(sinc>=0x20000L)                                 // we would skip at least one val?
   {
-   s_chan[ch].SB[29]+=(s_chan[ch].SB[30]-s_chan[ch].SB[29])/2; // add easy weight
-   if(s_chan[ch].sinc>=0x30000L)                               // we would skip even more vals?
-    s_chan[ch].SB[29]+=(s_chan[ch].SB[31]-s_chan[ch].SB[30])/2;// add additional next weight
+   SB[29]+=(SB[30]-SB[29])/2;                                  // add easy weight
+   if(sinc>=0x30000L)                               // we would skip even more vals?
+    SB[29]+=(SB[31]-SB[30])/2;                                 // add additional next weight
   }
 }
 
 ////////////////////////////////////////////////////////////////////////
 // helpers for gauss interpolation
 
-#define gval0 (((short*)(&s_chan[ch].SB[29]))[gpos])
-#define gval(x) (((short*)(&s_chan[ch].SB[29]))[(gpos+x)&3])
+#define gval0 (((short*)(&SB[29]))[gpos&3])
+#define gval(x) ((int)((short*)(&SB[29]))[(gpos+x)&3])
 
 #include "gauss_i.h"
 
@@ -255,6 +248,26 @@ INLINE void InterpolateDown(int ch)
 
 #include "xa.c"
 
+static void do_irq(void)
+{
+ //if(!(spu.spuStat & STAT_IRQ))
+ {
+  spu.spuStat |= STAT_IRQ;                             // asserted status?
+  if(spu.irqCallback) spu.irqCallback();
+ }
+}
+
+static int check_irq(int ch, unsigned char *pos)
+{
+ if((spu.spuCtrl & CTRL_IRQ) && pos == spu.pSpuIrq)
+ {
+  //printf("ch%d irq %04x\n", ch, pos - spu.spuMemC);
+  do_irq();
+  return 1;
+ }
+ return 0;
+}
+
 ////////////////////////////////////////////////////////////////////////
 // START SOUND... called by main thread to setup a new sound on a channel
 ////////////////////////////////////////////////////////////////////////
@@ -264,57 +277,40 @@ INLINE void StartSound(int ch)
  StartADSR(ch);
  StartREVERB(ch);
 
- // fussy timing issues - do in VoiceOn
- //s_chan[ch].pCurr=s_chan[ch].pStart;                   // set sample start
- //s_chan[ch].bStop=0;
- //s_chan[ch].bOn=1;
+ s_chan[ch].prevflags=2;
 
  s_chan[ch].SB[26]=0;                                  // init mixing vars
  s_chan[ch].SB[27]=0;
- s_chan[ch].iSBPos=28;
+ s_chan[ch].iSBPos=27;
 
+ s_chan[ch].SB[28]=0;
  s_chan[ch].SB[29]=0;                                  // init our interpolation helpers
  s_chan[ch].SB[30]=0;
+ s_chan[ch].SB[31]=0;
+ s_chan[ch].spos=0;
 
- if(iUseInterpolation>=2)                              // gauss interpolation?
-      {s_chan[ch].spos=0x30000L;s_chan[ch].SB[28]=0;}  // -> start with more decoding
- else {s_chan[ch].spos=0x10000L;s_chan[ch].SB[31]=0;}  // -> no/simple interpolation starts with one 44100 decoding
-
- dwNewChannel&=~(1<<ch);                               // clear new channel bit
+ spu.dwNewChannel&=~(1<<ch);                           // clear new channel bit
+ spu.dwChannelOn|=1<<ch;
+ spu.dwChannelDead&=~(1<<ch);
 }
 
 ////////////////////////////////////////////////////////////////////////
 // ALL KIND OF HELPERS
 ////////////////////////////////////////////////////////////////////////
 
-INLINE void VoiceChangeFrequency(int ch)
+INLINE int FModChangeFrequency(int *SB, int pitch, int ns)
 {
- s_chan[ch].iUsedFreq=s_chan[ch].iActFreq;             // -> take it and calc steps
- s_chan[ch].sinc=s_chan[ch].iRawPitch<<4;
- if(!s_chan[ch].sinc) s_chan[ch].sinc=1;
- if(iUseInterpolation==1) s_chan[ch].SB[32]=1;         // -> freq change in simle imterpolation mode: set flag
-}
-
-////////////////////////////////////////////////////////////////////////
-
-INLINE int FModChangeFrequency(int ch,int ns)
-{
- int NP=s_chan[ch].iRawPitch;
+ unsigned int NP=pitch;
  int sinc;
 
- NP=((32768L+iFMod[ns])*NP)/32768L;
+ NP=((32768L+iFMod[ns])*NP)>>15;
 
  if(NP>0x3fff) NP=0x3fff;
  if(NP<0x1)    NP=0x1;
 
- NP=(44100L*NP)/(4096L);                               // calc frequency
-
- s_chan[ch].iActFreq=NP;
- s_chan[ch].iUsedFreq=NP;
- sinc=(((NP/10)<<16)/4410);
- if(!sinc) sinc=1;
- if(iUseInterpolation==1)                              // freq change in simple interpolation mode
-  s_chan[ch].SB[32]=1;
+ sinc=NP<<4;                                           // calc frequency
+ if(spu_config.iUseInterpolation==1)                   // freq change in simple interpolation mode
+  SB[32]=1;
  iFMod[ns]=0;
 
  return sinc;
@@ -322,50 +318,50 @@ INLINE int FModChangeFrequency(int ch,int ns)
 
 ////////////////////////////////////////////////////////////////////////
 
-INLINE void StoreInterpolationVal(int ch,int fa)
+INLINE void StoreInterpolationVal(int *SB, int sinc, int fa, int fmod_freq)
 {
- if(s_chan[ch].bFMod==2)                               // fmod freq channel
-  s_chan[ch].SB[29]=fa;
+ if(fmod_freq)                                         // fmod freq channel
+  SB[29]=fa;
  else
   {
    ssat32_to_16(fa);
 
-   if(iUseInterpolation>=2)                            // gauss/cubic interpolation
-    {     
-     int gpos = s_chan[ch].SB[28];
-     gval0 = fa;          
+   if(spu_config.iUseInterpolation>=2)                 // gauss/cubic interpolation
+    {
+     int gpos = SB[28];
+     gval0 = fa;
      gpos = (gpos+1) & 3;
-     s_chan[ch].SB[28] = gpos;
+     SB[28] = gpos;
     }
    else
-   if(iUseInterpolation==1)                            // simple interpolation
+   if(spu_config.iUseInterpolation==1)                 // simple interpolation
     {
-     s_chan[ch].SB[28] = 0;                    
-     s_chan[ch].SB[29] = s_chan[ch].SB[30];            // -> helpers for simple linear interpolation: delay real val for two slots, and calc the two deltas, for a 'look at the future behaviour'
-     s_chan[ch].SB[30] = s_chan[ch].SB[31];
-     s_chan[ch].SB[31] = fa;
-     s_chan[ch].SB[32] = 1;                            // -> flag: calc new interolation
+     SB[28] = 0;
+     SB[29] = SB[30];                                  // -> helpers for simple linear interpolation: delay real val for two slots, and calc the two deltas, for a 'look at the future behaviour'
+     SB[30] = SB[31];
+     SB[31] = fa;
+     SB[32] = 1;                                       // -> flag: calc new interolation
     }
-   else s_chan[ch].SB[29]=fa;                          // no interpolation
+   else SB[29]=fa;                                     // no interpolation
   }
 }
 
 ////////////////////////////////////////////////////////////////////////
 
-INLINE int iGetInterpolationVal(int ch)
+INLINE int iGetInterpolationVal(int *SB, int sinc, int spos, int fmod_freq)
 {
  int fa;
 
- if(s_chan[ch].bFMod==2) return s_chan[ch].SB[29];
+ if(fmod_freq) return SB[29];
 
- switch(iUseInterpolation)
-  {   
+ switch(spu_config.iUseInterpolation)
+  {
    //--------------------------------------------------//
    case 3:                                             // cubic interpolation
     {
      long xd;int gpos;
-     xd = ((s_chan[ch].spos) >> 1)+1;
-     gpos = s_chan[ch].SB[28];
+     xd = (spos >> 1)+1;
+     gpos = SB[28];
 
      fa  = gval(3) - 3*gval(2) + 3*gval(1) - gval0;
      fa *= (xd - (2<<15)) / 6;
@@ -383,9 +379,9 @@ INLINE int iGetInterpolationVal(int ch)
    case 2:                                             // gauss interpolation
     {
      int vl, vr;int gpos;
-     vl = (s_chan[ch].spos >> 6) & ~3;
-     gpos = s_chan[ch].SB[28];
-     vr=(gauss[vl]*gval0)&~2047;
+     vl = (spos >> 6) & ~3;
+     gpos = SB[28];
+     vr=(gauss[vl]*(int)gval0)&~2047;
      vr+=(gauss[vl+1]*gval(1))&~2047;
      vr+=(gauss[vl+2]*gval(2))&~2047;
      vr+=(gauss[vl+3]*gval(3))&~2047;
@@ -394,15 +390,15 @@ INLINE int iGetInterpolationVal(int ch)
    //--------------------------------------------------//
    case 1:                                             // simple interpolation
     {
-     if(s_chan[ch].sinc<0x10000L)                      // -> upsampling?
-          InterpolateUp(ch);                           // --> interpolate up
-     else InterpolateDown(ch);                         // --> else down
-     fa=s_chan[ch].SB[29];
+     if(sinc<0x10000L)                                 // -> upsampling?
+          InterpolateUp(SB, sinc);                     // --> interpolate up
+     else InterpolateDown(SB, sinc);                   // --> else down
+     fa=SB[29];
     } break;
    //--------------------------------------------------//
    default:                                            // no interpolation
     {
-     fa=s_chan[ch].SB[29];                  
+     fa=SB[29];
     } break;
    //--------------------------------------------------//
   }
@@ -410,15 +406,6 @@ INLINE int iGetInterpolationVal(int ch)
  return fa;
 }
 
-static void do_irq(void)
-{
- if(!(spuStat & STAT_IRQ))
- {
-  spuStat |= STAT_IRQ;
-  if(irqCallback) irqCallback();
- }
-}
-
 static void decode_block_data(int *dest, const unsigned char *src, int predict_nr, int shift_factor)
 {
  int nSample;
@@ -447,60 +434,48 @@ static void decode_block_data(int *dest, const unsigned char *src, int predict_n
  }
 }
 
-static int decode_block(int ch)
+static int decode_block(int ch, int *SB)
 {
  unsigned char *start;
- int predict_nr,shift_factor,flags;
+ int predict_nr, shift_factor, flags;
  int ret = 0;
 
- start=s_chan[ch].pCurr;                   // set up the current pos
- if(dwPendingChanOff&(1<<ch))
- {
-  dwChannelOn&=~(1<<ch);                   // -> turn everything off
-  dwPendingChanOff&=~(1<<ch);
-  s_chan[ch].bStop=1;
-  s_chan[ch].ADSRX.EnvelopeVol=0;
- }
-
- //////////////////////////////////////////// irq check
+ start = s_chan[ch].pCurr;                 // set up the current pos
+ if (start == spu.spuMemC)                 // ?
+  ret = 1;
 
- if(spuCtrl&CTRL_IRQ)
+ if (s_chan[ch].prevflags & 1)             // 1: stop/loop
  {
-  if(pSpuIrq == start)                     // irq address reached?
-  {
-   do_irq();                               // -> call main emu
+  if (!(s_chan[ch].prevflags & 2))
    ret = 1;
-  }
+
+  start = s_chan[ch].pLoop;
  }
+ else
+  check_irq(ch, start);                    // hack, see check_irq below..
 
- predict_nr=(int)start[0];
- shift_factor=predict_nr&0xf;
+ predict_nr = (int)start[0];
+ shift_factor = predict_nr & 0xf;
  predict_nr >>= 4;
 
- decode_block_data(s_chan[ch].SB, start + 2, predict_nr, shift_factor);
+ decode_block_data(SB, start + 2, predict_nr, shift_factor);
 
- //////////////////////////////////////////// flag handler
+ flags = start[1];
+ if (flags & 4)
+  s_chan[ch].pLoop = start;                // loop adress
 
- flags=(int)start[1];
- if(flags&4)
-  s_chan[ch].pLoop=start;                  // loop adress
-
- start+=16;
- if(flags&1)                               // 1: stop/loop
- {
-  if(!(flags&2))
-   dwPendingChanOff|=1<<ch;
+ start += 16;
 
+ if (flags & 1) {                          // 1: stop/loop
   start = s_chan[ch].pLoop;
+  check_irq(ch, start);                    // hack.. :(
  }
 
- if (start - spuMemC >= 0x80000) {
-  // most likely wrong
-  start = spuMemC;
-  printf("ch%d oflow\n", ch);
- }
+ if (start - spu.spuMemC >= 0x80000)
+  start = spu.spuMemC;
 
  s_chan[ch].pCurr = start;                 // store values for next cycle
+ s_chan[ch].prevflags = flags;
 
  return ret;
 }
@@ -509,70 +484,138 @@ static int decode_block(int ch)
 static int skip_block(int ch)
 {
  unsigned char *start = s_chan[ch].pCurr;
- int flags = start[1];
+ int flags;
  int ret = 0;
 
- // Tron Bonne hack, probably wrong (could be wrong memory contents..)
- if(flags & ~7) flags = 0;
+ if (s_chan[ch].prevflags & 1) {
+  if (!(s_chan[ch].prevflags & 2))
+   ret = 1;
 
- if(start == pSpuIrq)
- {
-  do_irq();
-  ret = 1;
+  start = s_chan[ch].pLoop;
  }
+ else
+  check_irq(ch, start);
 
- if(flags & 4)
-  s_chan[ch].pLoop=start;
+ flags = start[1];
+ if (flags & 4)
+  s_chan[ch].pLoop = start;
 
- s_chan[ch].pCurr += 16;
+ start += 16;
 
- if(flags & 1)
-  s_chan[ch].pCurr = s_chan[ch].pLoop;
+ if (flags & 1) {
+  start = s_chan[ch].pLoop;
+  check_irq(ch, start);
+ }
+
+ s_chan[ch].pCurr = start;
+ s_chan[ch].prevflags = flags;
 
  return ret;
 }
 
+#ifdef THREAD_ENABLED
+
+static int decode_block_work(int ch, int *SB)
+{
+ int predict_nr, shift_factor, flags;
+ const unsigned char *ram = worker->ram;
+ int start = worker->ch[ch].start;
+ int loop = worker->ch[ch].loop;
+
+ predict_nr = ram[start];
+ shift_factor = predict_nr & 0xf;
+ predict_nr >>= 4;
+
+ decode_block_data(SB, ram + start + 2, predict_nr, shift_factor);
+
+ flags = ram[start + 1];
+ if (flags & 4)
+  loop = start;                            // loop adress
+
+ start += 16;
+
+ if (flags & 1)                            // 1: stop/loop
+  start = loop;
+
+ worker->ch[ch].start = start & 0x7ffff;
+ worker->ch[ch].loop = loop;
+
+ return 0;
+}
+
+#endif
+
+// if irq is going to trigger sooner than in upd_samples, set upd_samples
+static void scan_for_irq(int ch, unsigned int *upd_samples)
+{
+ int pos, sinc, sinc_inv, end;
+ unsigned char *block;
+ int flags;
+
+ block = s_chan[ch].pCurr;
+ pos = s_chan[ch].spos;
+ sinc = s_chan[ch].sinc;
+ end = pos + *upd_samples * sinc;
+
+ pos += (28 - s_chan[ch].iSBPos) << 16;
+ while (pos < end)
+ {
+  if (block == spu.pSpuIrq)
+   break;
+  flags = block[1];
+  block += 16;
+  if (flags & 1) {                          // 1: stop/loop
+   block = s_chan[ch].pLoop;
+   if (block == spu.pSpuIrq)                // hack.. (see decode_block)
+    break;
+  }
+  pos += 28 << 16;
+ }
+
+ if (pos < end)
+ {
+  sinc_inv = s_chan[ch].sinc_inv;
+  if (sinc_inv == 0)
+   sinc_inv = s_chan[ch].sinc_inv = (0x80000000u / (uint32_t)sinc) << 1;
+
+  pos -= s_chan[ch].spos;
+  *upd_samples = (((uint64_t)pos * sinc_inv) >> 32) + 1;
+  //xprintf("ch%02d: irq sched: %3d %03d\n",
+  // ch, *upd_samples, *upd_samples * 60 * 263 / 44100);
+ }
+}
+
 #define make_do_samples(name, fmod_code, interp_start, interp1_code, interp2_code, interp_end) \
-static int do_samples_##name(int ch, int ns, int ns_to) \
+static noinline int do_samples_##name(int (*decode_f)(int ch, int *SB), int ch, \
+ int ns_to, int *SB, int sinc, int *spos, int *sbpos) \
 {                                            \
- int sinc = s_chan[ch].sinc;                 \
- int spos = s_chan[ch].spos;                 \
- int sbpos = s_chan[ch].iSBPos;              \
- int *SB = s_chan[ch].SB;                    \
- int ret = -1;                               \
- int d, fa;                                  \
+ int ns, d, fa;                              \
+ int ret = ns_to;                            \
  interp_start;                               \
                                              \
- for (; ns < ns_to; ns++)                    \
+ for (ns = 0; ns < ns_to; ns++)              \
  {                                           \
   fmod_code;                                 \
                                              \
-  while (spos >= 0x10000)                    \
+  *spos += sinc;                             \
+  while (*spos >= 0x10000)                   \
   {                                          \
-   if(sbpos == 28)                           \
+   fa = SB[(*sbpos)++];                      \
+   if (*sbpos >= 28)                         \
    {                                         \
-    sbpos = 0;                               \
-    d = decode_block(ch);                    \
-    if(d && iSPUIRQWait)                     \
-    {                                        \
+    *sbpos = 0;                              \
+    d = decode_f(ch, SB);                    \
+    if (d && ns < ret)                       \
      ret = ns;                               \
-     goto out;                               \
-    }                                        \
    }                                         \
                                              \
-   fa = SB[sbpos++];                         \
    interp1_code;                             \
-   spos -= 0x10000;                          \
+   *spos -= 0x10000;                         \
   }                                          \
                                              \
   interp2_code;                              \
-  spos += sinc;                              \
  }                                           \
                                              \
-out:                                         \
- s_chan[ch].sinc = sinc;                     \
- s_chan[ch].spos = spos;                     \
- s_chan[ch].iSBPos = sbpos;                  \
  interp_end;                                 \
                                              \
  return ret;                                 \
@@ -580,67 +623,99 @@ out:                                         \
 
 #define fmod_recv_check \
   if(s_chan[ch].bFMod==1 && iFMod[ns]) \
-    sinc = FModChangeFrequency(ch,ns)
+    sinc = FModChangeFrequency(SB, s_chan[ch].iRawPitch, ns)
 
 make_do_samples(default, fmod_recv_check, ,
-  StoreInterpolationVal(ch, fa),
-  ChanBuf[ns] = iGetInterpolationVal(ch), )
-make_do_samples(noint, , fa = s_chan[ch].SB[29], , ChanBuf[ns] = fa, s_chan[ch].SB[29] = fa)
+  StoreInterpolationVal(SB, sinc, fa, s_chan[ch].bFMod==2),
+  ChanBuf[ns] = iGetInterpolationVal(SB, sinc, *spos, s_chan[ch].bFMod==2), )
+make_do_samples(noint, , fa = SB[29], , ChanBuf[ns] = fa, SB[29] = fa)
 
 #define simple_interp_store \
-  s_chan[ch].SB[28] = 0; \
-  s_chan[ch].SB[29] = s_chan[ch].SB[30]; \
-  s_chan[ch].SB[30] = s_chan[ch].SB[31]; \
-  s_chan[ch].SB[31] = fa; \
-  s_chan[ch].SB[32] = 1
+  SB[28] = 0; \
+  SB[29] = SB[30]; \
+  SB[30] = SB[31]; \
+  SB[31] = fa; \
+  SB[32] = 1
 
 #define simple_interp_get \
-  if(sinc<0x10000)          /* -> upsampling? */ \
-       InterpolateUp(ch);   /* --> interpolate up */ \
-  else InterpolateDown(ch); /* --> else down */ \
-  ChanBuf[ns] = s_chan[ch].SB[29]
+  if(sinc<0x10000)                /* -> upsampling? */ \
+       InterpolateUp(SB, sinc);   /* --> interpolate up */ \
+  else InterpolateDown(SB, sinc); /* --> else down */ \
+  ChanBuf[ns] = SB[29]
 
 make_do_samples(simple, , ,
   simple_interp_store, simple_interp_get, )
 
-static int do_samples_noise(int ch, int ns, int ns_to)
+static int do_samples_skip(int ch, int ns_to)
 {
- int level, shift, bit;
+ int ret = ns_to, ns, d;
+
+ s_chan[ch].spos += s_chan[ch].iSBPos << 16;
 
- s_chan[ch].spos += s_chan[ch].sinc * (ns_to - ns);
- while (s_chan[ch].spos >= 28*0x10000)
+ for (ns = 0; ns < ns_to; ns++)
  {
-  skip_block(ch);
-  s_chan[ch].spos -= 28*0x10000;
+  s_chan[ch].spos += s_chan[ch].sinc;
+  while (s_chan[ch].spos >= 28*0x10000)
+  {
+   d = skip_block(ch);
+   if (d && ns < ret)
+    ret = ns;
+   s_chan[ch].spos -= 28*0x10000;
+  }
  }
 
+ s_chan[ch].iSBPos = s_chan[ch].spos >> 16;
+ s_chan[ch].spos &= 0xffff;
+
+ return ret;
+}
+
+static void do_lsfr_samples(int ns_to, int ctrl,
+ unsigned int *dwNoiseCount, unsigned int *dwNoiseVal)
+{
+ unsigned int counter = *dwNoiseCount;
+ unsigned int val = *dwNoiseVal;
+ unsigned int level, shift, bit;
+ int ns;
+
  // modified from DrHell/shalma, no fraction
- level = (spuCtrl >> 10) & 0x0f;
+ level = (ctrl >> 10) & 0x0f;
  level = 0x8000 >> level;
 
- for (; ns < ns_to; ns++)
+ for (ns = 0; ns < ns_to; ns++)
  {
-  dwNoiseCount += 2;
-  if (dwNoiseCount >= level)
+  counter += 2;
+  if (counter >= level)
   {
-   dwNoiseCount -= level;
-   shift = (dwNoiseVal >> 10) & 0x1f;
+   counter -= level;
+   shift = (val >> 10) & 0x1f;
    bit = (0x69696969 >> shift) & 1;
-   if (dwNoiseVal & 0x8000)
-    bit ^= 1;
-   dwNoiseVal = (dwNoiseVal << 1) | bit;
+   bit ^= (val >> 15) & 1;
+   val = (val << 1) | bit;
   }
 
-  ChanBuf[ns] = (signed short)dwNoiseVal;
+  ChanBuf[ns] = (signed short)val;
  }
 
- return -1;
+ *dwNoiseCount = counter;
+ *dwNoiseVal = val;
+}
+
+static int do_samples_noise(int ch, int ns_to)
+{
+ int ret;
+
+ ret = do_samples_skip(ch, ns_to);
+
+ do_lsfr_samples(ns_to, spu.spuCtrl, &spu.dwNoiseCount, &spu.dwNoiseVal);
+
+ return ret;
 }
 
-#ifdef __arm__
-// asm code
+#ifdef HAVE_ARMV5
+// asm code; lv and rv must be 0-3fff
 extern void mix_chan(int start, int count, int lv, int rv);
-extern void mix_chan_rvb(int start, int count, int lv, int rv);
+extern void mix_chan_rvb(int start, int count, int lv, int rv, int *rvb);
 #else
 static void mix_chan(int start, int count, int lv, int rv)
 {
@@ -659,10 +734,10 @@ static void mix_chan(int start, int count, int lv, int rv)
   }
 }
 
-static void mix_chan_rvb(int start, int count, int lv, int rv)
+static void mix_chan_rvb(int start, int count, int lv, int rv, int *rvb)
 {
  int *dst = SSumLR + start * 2;
- int *drvb = sRVBStart + start * 2;
+ int *drvb = rvb + start * 2;
  const int *src = ChanBuf + start;
  int l, r;
 
@@ -680,269 +755,440 @@ static void mix_chan_rvb(int start, int count, int lv, int rv)
 }
 #endif
 
-////////////////////////////////////////////////////////////////////////
-// MAIN SPU FUNCTION
-// here is the main job handler... thread, timer or direct func call
-// basically the whole sound processing is done in this fat func!
-////////////////////////////////////////////////////////////////////////
-
-// 5 ms waiting phase, if buffer is full and no new sound has to get started
-// .. can be made smaller (smallest val: 1 ms), but bigger waits give
-// better performance
+// 0x0800-0x0bff  Voice 1
+// 0x0c00-0x0fff  Voice 3
+static noinline void do_decode_bufs(unsigned short *mem, int which,
+ int count, int decode_pos)
+{
+ unsigned short *dst = &mem[0x800/2 + which*0x400/2];
+ const int *src = ChanBuf;
+ int cursor = decode_pos;
 
-#define PAUSE_W 5
-#define PAUSE_L 5000
+ while (count-- > 0)
+  {
+   cursor &= 0x1ff;
+   dst[cursor] = *src++;
+   cursor++;
+  }
 
-////////////////////////////////////////////////////////////////////////
+ // decode_pos is updated and irqs are checked later, after voice loop
+}
 
-static void *MAINThread(void *arg)
+static void do_silent_chans(int ns_to, int silentch)
 {
- int volmult = iVolume;
- int ns,ns_from,ns_to;
- int ch,d,silentch;
- int bIRQReturn=0;
+ int ch;
 
- while(!bEndThread)                                    // until we are shutting down
+ for (ch = 0; ch < MAXCHAN; ch++)
   {
-   // ok, at the beginning we are looking if there is
-   // enuff free place in the dsound/oss buffer to
-   // fill in new data, or if there is a new channel to start.
-   // if not, we wait (thread) or return (timer/spuasync)
-   // until enuff free place is available/a new channel gets
-   // started
-
-   if(dwNewChannel)                                    // new channel should start immedately?
-    {                                                  // (at least one bit 0 ... MAXCHANNEL is set?)
-     iSecureStart++;                                   // -> set iSecure
-     if(iSecureStart>5) iSecureStart=0;                //    (if it is set 5 times - that means on 5 tries a new samples has been started - in a row, we will reset it, to give the sound update a chance)
-    }
-   else iSecureStart=0;                                // 0: no new channel should start
+   if (!(silentch & (1<<ch))) continue;            // already handled
+   if (spu.dwChannelDead & (1<<ch)) continue;
+   if (s_chan[ch].pCurr > spu.pSpuIrq && s_chan[ch].pLoop > spu.pSpuIrq)
+    continue;
 
-   while(!iSecureStart && !bEndThread &&               // no new start? no thread end?
-         (SoundGetBytesBuffered()>TESTSIZE))           // and still enuff data in sound buffer?
+   s_chan[ch].spos += s_chan[ch].iSBPos << 16;
+   s_chan[ch].iSBPos = 0;
+
+   s_chan[ch].spos += s_chan[ch].sinc * ns_to;
+   while (s_chan[ch].spos >= 28 * 0x10000)
     {
-     iSecureStart=0;                                   // reset secure
+     unsigned char *start = s_chan[ch].pCurr;
 
-     if(iUseTimer) return 0;                           // linux no-thread mode? bye
-     usleep(PAUSE_L);                                  // else sleep for x ms (linux)
+     skip_block(ch);
+     if (start == s_chan[ch].pCurr || start - spu.spuMemC < 0x1000)
+      {
+       // looping on self or stopped(?)
+       spu.dwChannelDead |= 1<<ch;
+       s_chan[ch].spos = 0;
+       break;
+      }
 
-     if(dwNewChannel) iSecureStart=1;                  // if a new channel kicks in (or, of course, sound buffer runs low), we will leave the loop
+     s_chan[ch].spos -= 28 * 0x10000;
     }
+  }
+}
+
+static void do_channels(int ns_to)
+{
+ unsigned int mask;
+ int *SB, sinc;
+ int ch, d;
 
-   //--------------------------------------------------// continue from irq handling in timer mode? 
+ InitREVERB(ns_to);
 
-   ns_from=0;
-   ns_to=NSSIZE;
-   ch=0;
-   if(lastch>=0)                                       // will be -1 if no continue is pending
+ mask = spu.dwChannelOn & 0xffffff;
+ for (ch = 0; mask != 0; ch++, mask >>= 1)         // loop em all...
+  {
+   if (!(mask & 1)) continue;                      // channel not playing? next
+
+   SB = s_chan[ch].SB;
+   sinc = s_chan[ch].sinc;
+
+   if (s_chan[ch].bNoise)
+    d = do_samples_noise(ch, ns_to);
+   else if (s_chan[ch].bFMod == 2
+         || (s_chan[ch].bFMod == 0 && spu_config.iUseInterpolation == 0))
+    d = do_samples_noint(decode_block, ch, ns_to,
+          SB, sinc, &s_chan[ch].spos, &s_chan[ch].iSBPos);
+   else if (s_chan[ch].bFMod == 0 && spu_config.iUseInterpolation == 1)
+    d = do_samples_simple(decode_block, ch, ns_to,
+          SB, sinc, &s_chan[ch].spos, &s_chan[ch].iSBPos);
+   else
+    d = do_samples_default(decode_block, ch, ns_to,
+          SB, sinc, &s_chan[ch].spos, &s_chan[ch].iSBPos);
+
+   d = MixADSR(&s_chan[ch].ADSRX, d);
+   if (d < ns_to) {
+    spu.dwChannelOn &= ~(1 << ch);
+    s_chan[ch].ADSRX.EnvelopeVol = 0;
+    memset(&ChanBuf[d], 0, (ns_to - d) * sizeof(ChanBuf[0]));
+   }
+
+   if (ch == 1 || ch == 3)
     {
-     ch=lastch; ns_from=lastns; lastch=-1;             // -> setup all kind of vars to continue
+     do_decode_bufs(spu.spuMem, ch/2, ns_to, spu.decode_pos);
+     spu.decode_dirty_ch |= 1 << ch;
     }
 
-   silentch=~(dwChannelOn|dwNewChannel);
+   if (s_chan[ch].bFMod == 2)                      // fmod freq channel
+    memcpy(iFMod, &ChanBuf, ns_to * sizeof(iFMod[0]));
+   if (s_chan[ch].bRVBActive)
+    mix_chan_rvb(0, ns_to, s_chan[ch].iLeftVolume, s_chan[ch].iRightVolume, spu.sRVBStart);
+   else
+    mix_chan(0, ns_to, s_chan[ch].iLeftVolume, s_chan[ch].iRightVolume);
+  }
+}
+
+static void do_samples_finish(int ns_to, int silentch, int decode_pos);
 
-   //--------------------------------------------------//
-   //- main channel loop                              -// 
-   //--------------------------------------------------//
+// optional worker thread handling
+
+#ifdef THREAD_ENABLED
+
+static void queue_channel_work(int ns_to, int silentch)
+{
+ unsigned int mask;
+ int ch;
+
+ worker->ns_to = ns_to;
+ worker->ctrl = spu.spuCtrl;
+ worker->decode_pos = spu.decode_pos;
+ worker->silentch = silentch;
+ worker->sRVBStart = spu.sRVBStart;
+ worker->ram = spu.spuMemC;
+
+ mask = worker->chmask = spu.dwChannelOn & 0xffffff;
+ for (ch = 0; mask != 0; ch++, mask >>= 1)
+  {
+   if (!(mask & 1)) continue;
+
+   worker->ch[ch].spos = s_chan[ch].spos;
+   worker->ch[ch].sbpos = s_chan[ch].iSBPos;
+   worker->ch[ch].sinc = s_chan[ch].sinc;
+   worker->ch[ch].adsr = s_chan[ch].ADSRX;
+   worker->ch[ch].start = s_chan[ch].pCurr - spu.spuMemC;
+   worker->ch[ch].loop = s_chan[ch].pLoop - spu.spuMemC;
+   if (s_chan[ch].prevflags & 1)
+    worker->ch[ch].start = worker->ch[ch].loop;
+
+   worker->ch[ch].ns_to = do_samples_skip(ch, ns_to);
+  }
+
+ worker->pending = 1;
+ sem_post(&worker->sem_avail);
+}
+
+static void do_channel_work(void)
+{
+ unsigned int mask, endmask = 0;
+ unsigned int decode_dirty_ch = 0;
+ int *SB, sinc, spos, sbpos;
+ int d, ch, ns_to;
+
+ ns_to = worker->ns_to;
+ memset(worker->sRVBStart, 0, ns_to * sizeof(worker->sRVBStart[0]) * 2);
+
+ mask = worker->chmask;
+ for (ch = 0; mask != 0; ch++, mask >>= 1)
+  {
+   if (!(mask & 1)) continue;
+
+   d = worker->ch[ch].ns_to;
+   spos = worker->ch[ch].spos;
+   sbpos = worker->ch[ch].sbpos;
+   sinc = worker->ch[ch].sinc;
+   SB = s_chan[ch].SB;
+
+   if (s_chan[ch].bNoise)
+    do_lsfr_samples(d, worker->ctrl, &spu.dwNoiseCount, &spu.dwNoiseVal);
+   else if (s_chan[ch].bFMod == 2
+         || (s_chan[ch].bFMod == 0 && spu_config.iUseInterpolation == 0))
+    do_samples_noint(decode_block_work, ch, d, SB, sinc, &spos, &sbpos);
+   else if (s_chan[ch].bFMod == 0 && spu_config.iUseInterpolation == 1)
+    do_samples_simple(decode_block_work, ch, d, SB, sinc, &spos, &sbpos);
+   else
+    do_samples_default(decode_block_work, ch, d, SB, sinc, &spos, &sbpos);
+
+   d = MixADSR(&worker->ch[ch].adsr, d);
+   if (d < ns_to) {
+    endmask |= 1 << ch;
+    worker->ch[ch].adsr.EnvelopeVol = 0;
+    memset(&ChanBuf[d], 0, (ns_to - d) * sizeof(ChanBuf[0]));
+   }
+
+   if (ch == 1 || ch == 3)
     {
-     for(;ch<MAXCHAN;ch++)                             // loop em all... we will collect 1 ms of sound of each playing channel
-      {
-       if(dwNewChannel&(1<<ch)) StartSound(ch);        // start new sound
-       if(!(dwChannelOn&(1<<ch))) continue;            // channel not playing? next
-
-       if(s_chan[ch].iActFreq!=s_chan[ch].iUsedFreq)   // new psx frequency?
-        VoiceChangeFrequency(ch);
-
-       if(s_chan[ch].bNoise)
-        d=do_samples_noise(ch, ns_from, ns_to);
-       else if(s_chan[ch].bFMod==2 || (s_chan[ch].bFMod==0 && iUseInterpolation==0))
-        d=do_samples_noint(ch, ns_from, ns_to);
-       else if(s_chan[ch].bFMod==0 && iUseInterpolation==1)
-        d=do_samples_simple(ch, ns_from, ns_to);
-       else
-        d=do_samples_default(ch, ns_from, ns_to);
-       if(d>=0)
-        {
-         bIRQReturn=1;
-         lastch=ch; 
-         lastns=ns_to=d;
-         if(d==0)
-          break;
-        }
-
-       MixADSR(ch, ns_from, ns_to);
-
-       if(s_chan[ch].bFMod==2)                         // fmod freq channel
-        memcpy(iFMod, ChanBuf, sizeof(iFMod));
-       else if(s_chan[ch].bRVBActive)
-        mix_chan_rvb(ns_from,ns_to-ns_from,s_chan[ch].iLeftVolume,s_chan[ch].iRightVolume);
-       else
-        mix_chan(ns_from,ns_to-ns_from,s_chan[ch].iLeftVolume,s_chan[ch].iRightVolume);
-      }
+     do_decode_bufs((void *)worker->ram, ch/2, ns_to, worker->decode_pos);
+     decode_dirty_ch |= 1 << ch;
     }
 
-    // advance "stopped" channels that can cause irqs
-    // (all chans are always playing on the real thing..)
-    if(!bIRQReturn && (spuCtrl&CTRL_IRQ))
-     for(ch=0;ch<MAXCHAN;ch++)
-      {
-       if(!(silentch&(1<<ch))) continue;               // already handled
-       if(dwChannelDead&(1<<ch)) continue;
-       if(s_chan[ch].pCurr > pSpuIrq && s_chan[ch].pLoop > pSpuIrq)
-        continue;
-
-       if(s_chan[ch].iActFreq!=s_chan[ch].iUsedFreq)   // new psx frequency?
-         VoiceChangeFrequency(ch);
-
-       s_chan[ch].spos += s_chan[ch].sinc * NSSIZE;
-       while(s_chan[ch].spos >= 28 * 0x10000)
-        {
-         unsigned char *start=s_chan[ch].pCurr;
-
-         // no need for bIRQReturn since the channel is silent
-         iSpuAsyncWait |= skip_block(ch);
-         if(start == s_chan[ch].pCurr)
-          {
-           // looping on self
-           dwChannelDead|=1<<ch;
-           break;
-          }
-
-         s_chan[ch].spos -= 28 * 0x10000;
-        }
-      }
+   if (s_chan[ch].bFMod == 2)                      // fmod freq channel
+    memcpy(iFMod, &ChanBuf, ns_to * sizeof(iFMod[0]));
+   if (s_chan[ch].bRVBActive)
+    mix_chan_rvb(0, ns_to, s_chan[ch].iLeftVolume, s_chan[ch].iRightVolume, worker->sRVBStart);
+   else
+    mix_chan(0, ns_to, s_chan[ch].iLeftVolume, s_chan[ch].iRightVolume);
+  }
+
+  worker->r_chan_end = endmask;
+  worker->r_decode_dirty = decode_dirty_ch;
+}
 
-    if(bIRQReturn && iSPUIRQWait)                      // special return for "spu irq - wait for cpu action"
+static void sync_worker_thread(void)
+{
+ unsigned int mask;
+ int ch;
+
+ if (!worker->pending)
+  return;
+
+ sem_wait(&worker->sem_done);
+ worker->pending = 0;
+
+ mask = worker->chmask;
+ for (ch = 0; mask != 0; ch++, mask >>= 1) {
+  if (!(mask & 1)) continue;
+
+  // be sure there was no keyoff while thread was working
+  if (s_chan[ch].ADSRX.State != ADSR_RELEASE)
+    s_chan[ch].ADSRX.State = worker->ch[ch].adsr.State;
+  s_chan[ch].ADSRX.EnvelopeVol = worker->ch[ch].adsr.EnvelopeVol;
+ }
+
+ spu.dwChannelOn &= ~worker->r_chan_end;
+ spu.decode_dirty_ch |= worker->r_decode_dirty;
+
+ do_samples_finish(worker->ns_to, worker->silentch,
+  worker->decode_pos);
+}
+
+#else
+
+static void queue_channel_work(int ns_to, int silentch) {}
+static void sync_worker_thread(void) {}
+
+#endif // THREAD_ENABLED
+
+////////////////////////////////////////////////////////////////////////
+// MAIN SPU FUNCTION
+// here is the main job handler...
+////////////////////////////////////////////////////////////////////////
+
+void do_samples(unsigned int cycles_to, int do_sync)
+{
+ unsigned int mask;
+ int ch, ns_to;
+ int silentch;
+ int cycle_diff;
+
+ cycle_diff = cycles_to - spu.cycles_played;
+ if (cycle_diff < -2*1048576 || cycle_diff > 2*1048576)
+  {
+   //xprintf("desync %u %d\n", cycles_to, cycle_diff);
+   spu.cycles_played = cycles_to;
+   return;
+  }
+
+ if (cycle_diff < 2 * 768)
+  return;
+
+ ns_to = (cycle_diff / 768 + 1) & ~1;
+ if (ns_to > NSSIZE) {
+  // should never happen
+  //xprintf("ns_to oflow %d %d\n", ns_to, NSSIZE);
+  ns_to = NSSIZE;
+ }
+
+  //////////////////////////////////////////////////////
+  // special irq handling in the decode buffers (0x0000-0x1000)
+  // we know:
+  // the decode buffers are located in spu memory in the following way:
+  // 0x0000-0x03ff  CD audio left
+  // 0x0400-0x07ff  CD audio right
+  // 0x0800-0x0bff  Voice 1
+  // 0x0c00-0x0fff  Voice 3
+  // and decoded data is 16 bit for one sample
+  // we assume:
+  // even if voices 1/3 are off or no cd audio is playing, the internal
+  // play positions will move on and wrap after 0x400 bytes.
+  // Therefore: we just need a pointer from spumem+0 to spumem+3ff, and
+  // increase this pointer on each sample by 2 bytes. If this pointer
+  // (or 0x400 offsets of this pointer) hits the spuirq address, we generate
+  // an IRQ.
+
+  if (unlikely((spu.spuCtrl & CTRL_IRQ)
+       && spu.pSpuIrq < spu.spuMemC+0x1000))
+   {
+    int irq_pos = (spu.pSpuIrq - spu.spuMemC) / 2 & 0x1ff;
+    int left = (irq_pos - spu.decode_pos) & 0x1ff;
+    if (0 < left && left <= ns_to)
      {
-      iSpuAsyncWait=1;
-      bIRQReturn=0;
-      if(iUseTimer!=2)
-       { 
-        DWORD dwWatchTime=timeGetTime_spu()+2500;
-
-        while(iSpuAsyncWait && !bEndThread && 
-              timeGetTime_spu()<dwWatchTime)
-            usleep(1000L);
-       continue;
-       }
-      else
-       {
-        return 0;
-       }
+      //xprintf("decoder irq %x\n", spu.decode_pos);
+      do_irq();
      }
+   }
 
+  if (worker != NULL)
+   sync_worker_thread();
+
+  mask = spu.dwNewChannel & 0xffffff;
+  for (ch = 0; mask != 0; ch++, mask >>= 1) {
+   if (mask & 1)
+    StartSound(ch);
+  }
+
+  silentch = ~spu.dwChannelOn & 0xffffff;
+
+  if (spu.dwChannelOn == 0) {
+   InitREVERB(ns_to);
+   do_samples_finish(ns_to, silentch, spu.decode_pos);
+  }
+  else {
+   if (do_sync || worker == NULL || !spu_config.iUseThread) {
+    do_channels(ns_to);
+    do_samples_finish(ns_to, silentch, spu.decode_pos);
+   }
+   else {
+    queue_channel_work(ns_to, silentch);
+   }
+  }
+
+  // advance "stopped" channels that can cause irqs
+  // (all chans are always playing on the real thing..)
+  if (spu.spuCtrl & CTRL_IRQ)
+   do_silent_chans(ns_to, silentch);
+
+  spu.cycles_played += ns_to * 768;
+  spu.decode_pos = (spu.decode_pos + ns_to) & 0x1ff;
+}
+
+static void do_samples_finish(int ns_to, int silentch, int decode_pos)
+{
+  int volmult = spu_config.iVolume;
+  int ns;
+  int d;
+
+  if(unlikely(silentch & spu.decode_dirty_ch & (1<<1))) // must clear silent channel decode buffers
+   {
+    memset(&spu.spuMem[0x800/2], 0, 0x400);
+    spu.decode_dirty_ch &= ~(1<<1);
+   }
+  if(unlikely(silentch & spu.decode_dirty_ch & (1<<3)))
+   {
+    memset(&spu.spuMem[0xc00/2], 0, 0x400);
+    spu.decode_dirty_ch &= ~(1<<3);
+   }
 
-  //---------------------------------------------------//
-  //- here we have another 1 ms of sound data
   //---------------------------------------------------//
   // mix XA infos (if any)
 
-  MixXA();
+  MixXA(ns_to, decode_pos);
   
   ///////////////////////////////////////////////////////
   // mix all channels (including reverb) into one buffer
 
-  if(iUseReverb)
-   REVERBDo();
+  if(spu_config.iUseReverb)
+   REVERBDo(ns_to);
 
-  if((spuCtrl&0x4000)==0) // muted? (rare, don't optimize for this)
+  if((spu.spuCtrl&0x4000)==0) // muted? (rare, don't optimize for this)
    {
-    memset(pS, 0, NSSIZE * 2 * sizeof(pS[0]));
-    pS += NSSIZE*2;
+    memset(spu.pS, 0, ns_to * 2 * sizeof(spu.pS[0]));
+    spu.pS += ns_to * 2;
    }
   else
-  for (ns = 0; ns < NSSIZE*2; )
+  for (ns = 0; ns < ns_to * 2; )
    {
     d = SSumLR[ns]; SSumLR[ns] = 0;
     d = d * volmult >> 10;
     ssat32_to_16(d);
-    *pS++ = d;
+    *spu.pS++ = d;
     ns++;
 
     d = SSumLR[ns]; SSumLR[ns] = 0;
     d = d * volmult >> 10;
     ssat32_to_16(d);
-    *pS++ = d;
+    *spu.pS++ = d;
     ns++;
    }
+}
 
-  //////////////////////////////////////////////////////                   
-  // special irq handling in the decode buffers (0x0000-0x1000)
-  // we know: 
-  // the decode buffers are located in spu memory in the following way:
-  // 0x0000-0x03ff  CD audio left
-  // 0x0400-0x07ff  CD audio right
-  // 0x0800-0x0bff  Voice 1
-  // 0x0c00-0x0fff  Voice 3
-  // and decoded data is 16 bit for one sample
-  // we assume: 
-  // even if voices 1/3 are off or no cd audio is playing, the internal
-  // play positions will move on and wrap after 0x400 bytes.
-  // Therefore: we just need a pointer from spumem+0 to spumem+3ff, and 
-  // increase this pointer on each sample by 2 bytes. If this pointer
-  // (or 0x400 offsets of this pointer) hits the spuirq address, we generate
-  // an IRQ. Only problem: the "wait for cpu" option is kinda hard to do here
-  // in some of Peops timer modes. So: we ignore this option here (for now).
+void schedule_next_irq(void)
+{
+ unsigned int upd_samples;
+ int ch;
 
-  if(pMixIrq)
-   {
-    for(ns=0;ns<NSSIZE;ns++)
-     {
-      if((spuCtrl&0x40) && pSpuIrq && pSpuIrq<spuMemC+0x1000)                 
-       {
-        for(ch=0;ch<4;ch++)
-         {
-          if(pSpuIrq>=pMixIrq+(ch*0x400) && pSpuIrq<pMixIrq+(ch*0x400)+2)
-           do_irq();
-         }
-       }
-      pMixIrq+=2;if(pMixIrq>spuMemC+0x3ff) pMixIrq=spuMemC;
-     }
-   }
+ if (spu.scheduleCallback == NULL)
+  return;
 
 InitREVERB();
upd_samples = 44100 / 50;
 
-  // feed the sound
-  // wanna have around 1/60 sec (16.666 ms) updates
-  if (iCycle++ > 16/FRAG_MSECS)
-   {
-    SoundFeedStreamData((unsigned char *)pSpuBuffer,
-                        ((unsigned char *)pS) - ((unsigned char *)pSpuBuffer));
-    pS = (short *)pSpuBuffer;
-    iCycle = 0;
-   }
- }
+ for (ch = 0; ch < MAXCHAN; ch++)
+ {
+  if (spu.dwChannelDead & (1 << ch))
+   continue;
+  if ((unsigned long)(spu.pSpuIrq - s_chan[ch].pCurr) > IRQ_NEAR_BLOCKS * 16
+    && (unsigned long)(spu.pSpuIrq - s_chan[ch].pLoop) > IRQ_NEAR_BLOCKS * 16)
+   continue;
 
- // end of big main loop...
+  scan_for_irq(ch, &upd_samples);
+ }
 
- bThreadEnded = 1;
+ if (unlikely(spu.pSpuIrq < spu.spuMemC + 0x1000))
+ {
+  int irq_pos = (spu.pSpuIrq - spu.spuMemC) / 2 & 0x1ff;
+  int left = (irq_pos - spu.decode_pos) & 0x1ff;
+  if (0 < left && left < upd_samples) {
+   //xprintf("decode: %3d (%3d/%3d)\n", left, spu.decode_pos, irq_pos);
+   upd_samples = left;
+  }
+ }
 
- return 0;
+ if (upd_samples < 44100 / 50)
+  spu.scheduleCallback(upd_samples * 768);
 }
 
 // SPU ASYNC... even newer epsxe func
 //  1 time every 'cycle' cycles... harhar
 
-void CALLBACK SPUasync(unsigned long cycle)
+// rearmed: called dynamically now
+
+void CALLBACK SPUasync(unsigned int cycle, unsigned int flags)
 {
- if(iSpuAsyncWait)
-  {
-   iSpuAsyncWait++;
-   if(iSpuAsyncWait<=16/FRAG_MSECS) return;
-   iSpuAsyncWait=0;
-  }
+ do_samples(cycle, 0);
 
- if(iUseTimer==2)                                      // special mode, only used in Linux by this spu (or if you enable the experimental Windows mode)
-  {
-   if(!bSpuInit) return;                               // -> no init, no call
+ if (spu.spuCtrl & CTRL_IRQ)
+  schedule_next_irq();
 
-   MAINThread(0);                                      // -> linux high-compat mode
+ if (flags & 1) {
+  out_current->feed(spu.pSpuBuffer, (unsigned char *)spu.pS - spu.pSpuBuffer);
+  spu.pS = (short *)spu.pSpuBuffer;
 
-   // abuse iSpuAsyncWait mechanism to reduce calls to above function
-   // to make it do larger chunks
-   // note: doing it less often than once per frame causes skips
-   iSpuAsyncWait=1;
+  if (spu_config.iTempo) {
+   if (!out_current->busy())
+    // cause more samples to be generated
+    // (and break some games because of bad sync)
+    spu.cycles_played -= 44100 / 60 / 2 * 768;
   }
+ }
 }
 
 // SPU UPDATE... new epsxe func
@@ -956,7 +1202,6 @@ void CALLBACK SPUasync(unsigned long cycle)
 
 void CALLBACK SPUupdate(void)
 {
- SPUasync(0);
 }
 
 // XA AUDIO
@@ -970,45 +1215,20 @@ void CALLBACK SPUplayADPCMchannel(xa_decode_t *xap)
 }
 
 // CDDA AUDIO
-void CALLBACK SPUplayCDDAchannel(short *pcm, int nbytes)
+int CALLBACK SPUplayCDDAchannel(short *pcm, int nbytes)
 {
- if (!pcm)      return;
- if (nbytes<=0) return;
+ if (!pcm)      return -1;
+ if (nbytes<=0) return -1;
 
- FeedCDDA((unsigned char *)pcm, nbytes);
return FeedCDDA((unsigned char *)pcm, nbytes);
 }
 
-// SETUPTIMER: init of certain buffers and threads/timers
-void SetupTimer(void)
+// to be called after state load
+void ClearWorkingState(void)
 {
  memset(SSumLR,0,sizeof(SSumLR));                      // init some mixing buffers
- memset(iFMod,0,NSSIZE*sizeof(int));
- pS=(short *)pSpuBuffer;                               // setup soundbuffer pointer
-
- bEndThread=0;                                         // init thread vars
- bThreadEnded=0; 
- bSpuInit=1;                                           // flag: we are inited
-
- if(!iUseTimer)                                        // linux: use thread
-  {
-   pthread_create(&thread, NULL, MAINThread, NULL);
-  }
-}
-
-// REMOVETIMER: kill threads/timers
-void RemoveTimer(void)
-{
- bEndThread=1;                                         // raise flag to end thread
-
- if(!iUseTimer)                                        // linux tread?
-  {
-   int i=0;
-   while(!bThreadEnded && i<2000) {usleep(1000L);i++;} // -> wait until thread has ended
-   if(thread!=(pthread_t)-1) {pthread_cancel(thread);thread=(pthread_t)-1;}  // -> cancel thread anyway
-  }
-
- bThreadEnded=0;                                       // no more spu is running
- bSpuInit=0;
+ memset(iFMod,0,sizeof(iFMod));     
+ spu.pS=(short *)spu.pSpuBuffer;                       // setup soundbuffer pointer
 }
 
 // SETUPSTREAMS: init most of the spu buffers
@@ -1016,90 +1236,152 @@ void SetupStreams(void)
 { 
  int i;
 
- pSpuBuffer=(unsigned char *)malloc(32768);            // alloc mixing buffer
-
- if(iUseReverb==1) i=88200*2;
- else              i=NSSIZE*2;
+ spu.pSpuBuffer = (unsigned char *)malloc(32768);      // alloc mixing buffer
+ spu.sRVBStart = (int *)malloc(NSSIZE*2*4);            // alloc reverb buffer
+ memset(spu.sRVBStart,0,NSSIZE*2*4);
 
- sRVBStart = (int *)malloc(i*4);                       // alloc reverb buffer
- memset(sRVBStart,0,i*4);
- sRVBEnd  = sRVBStart + i;
- sRVBPlay = sRVBStart;
-
- XAStart =                                             // alloc xa buffer
+ spu.XAStart =                                         // alloc xa buffer
   (uint32_t *)malloc(44100 * sizeof(uint32_t));
XAEnd   = XAStart + 44100;
XAPlay  = XAStart;
XAFeed  = XAStart;
spu.XAEnd   = spu.XAStart + 44100;
spu.XAPlay  = spu.XAStart;
spu.XAFeed  = spu.XAStart;
 
CDDAStart =                                           // alloc cdda buffer
-  (uint32_t *)malloc(16384 * sizeof(uint32_t));
CDDAEnd   = CDDAStart + 16384;
CDDAPlay  = CDDAStart;
CDDAFeed  = CDDAStart;
spu.CDDAStart =                                       // alloc cdda buffer
+  (uint32_t *)malloc(CDDA_BUFFER_SIZE);
spu.CDDAEnd   = spu.CDDAStart + 16384;
spu.CDDAPlay  = spu.CDDAStart;
spu.CDDAFeed  = spu.CDDAStart;
 
  for(i=0;i<MAXCHAN;i++)                                // loop sound channels
   {
-// we don't use mutex sync... not needed, would only 
-// slow us down:
-//   s_chan[i].hMutex=CreateMutex(NULL,FALSE,NULL);
    s_chan[i].ADSRX.SustainLevel = 0xf;                 // -> init sustain
-   s_chan[i].pLoop=spuMemC;
-   s_chan[i].pStart=spuMemC;
-   s_chan[i].pCurr=spuMemC;
+   s_chan[i].ADSRX.SustainIncrease = 1;
+   s_chan[i].pLoop=spu.spuMemC;
+   s_chan[i].pCurr=spu.spuMemC;
   }
 
-  pMixIrq=spuMemC;                                     // enable decoded buffer irqs by setting the address
+ ClearWorkingState();
+
+ spu.bSpuInit=1;                                       // flag: we are inited
 }
 
 // REMOVESTREAMS: free most buffer
 void RemoveStreams(void)
 { 
- free(pSpuBuffer);                                     // free mixing buffer
- pSpuBuffer = NULL;
- free(sRVBStart);                                      // free reverb buffer
- sRVBStart = NULL;
- free(XAStart);                                        // free XA buffer
- XAStart = NULL;
- free(CDDAStart);                                      // free CDDA buffer
- CDDAStart = NULL;
+ free(spu.pSpuBuffer);                                 // free mixing buffer
+ spu.pSpuBuffer = NULL;
+ free(spu.sRVBStart);                                  // free reverb buffer
+ spu.sRVBStart = NULL;
+ free(spu.XAStart);                                    // free XA buffer
+ spu.XAStart = NULL;
+ free(spu.CDDAStart);                                  // free CDDA buffer
+ spu.CDDAStart = NULL;
+}
+
+#ifdef THREAD_ENABLED
+
+static void *spu_worker_thread(void *unused)
+{
+ while (1) {
+  sem_wait(&worker->sem_avail);
+  if (worker->exit_thread)
+   break;
+
+  do_channel_work();
+
+  sem_post(&worker->sem_done);
+ }
+
+ return NULL;
+}
+
+static void init_spu_thread(void)
+{
+ int ret;
+
+ if (sysconf(_SC_NPROCESSORS_ONLN) <= 1)
+  return;
+
+ worker = calloc(1, sizeof(*worker));
+ if (worker == NULL)
+  return;
+ ret = sem_init(&worker->sem_avail, 0, 0);
+ if (ret != 0)
+  goto fail_sem_avail;
+ ret = sem_init(&worker->sem_done, 0, 0);
+ if (ret != 0)
+  goto fail_sem_done;
+
+ ret = pthread_create(&worker->thread, NULL, spu_worker_thread, NULL);
+ if (ret != 0)
+  goto fail_thread;
+
+ return;
+
+fail_thread:
+ sem_destroy(&worker->sem_done);
+fail_sem_done:
+ sem_destroy(&worker->sem_avail);
+fail_sem_avail:
+ free(worker);
+ worker = NULL;
 }
 
-// INIT/EXIT STUFF
+static void exit_spu_thread(void)
+{
+ if (worker == NULL)
+  return;
+ worker->exit_thread = 1;
+ sem_post(&worker->sem_avail);
+ pthread_join(worker->thread, NULL);
+ sem_destroy(&worker->sem_done);
+ sem_destroy(&worker->sem_avail);
+ free(worker);
+ worker = NULL;
+}
+
+#else // if !THREAD_ENABLED
+
+static void init_spu_thread(void)
+{
+}
+
+static void exit_spu_thread(void)
+{
+}
+
+#endif
 
 // SPUINIT: this func will be called first by the main emu
 long CALLBACK SPUinit(void)
 {
- spuMemC = (unsigned char *)spuMem;                    // just small setup
+ spu.spuMemC = (unsigned char *)spu.spuMem;            // just small setup
  memset((void *)&rvb, 0, sizeof(REVERBInfo));
  InitADSR();
 
- spuIrq = 0;
- spuAddr = 0xffffffff;
- bEndThread = 0;
- bThreadEnded = 0;
- spuMemC = (unsigned char *)spuMem;
- pMixIrq = 0;
- memset((void *)s_chan, 0, (MAXCHAN + 1) * sizeof(SPUCHAN));
- pSpuIrq = 0;
- //iSPUIRQWait = 0;
- lastch = -1;
-
- //ReadConfigSPU();                                      // read user stuff
+ spu.spuAddr = 0xffffffff;
+ spu.decode_pos = 0;
+ memset((void *)s_chan, 0, sizeof(s_chan));
+ spu.pSpuIrq = spu.spuMemC;
+
  SetupStreams();                                       // prepare streaming
 
+ if (spu_config.iVolume == 0)
+  spu_config.iVolume = 768; // 1024 is 1.0
+
+ init_spu_thread();
+
  return 0;
 }
 
 // SPUOPEN: called by main emu after init
 long CALLBACK SPUopen(void)
 {
- if (bSPUIsOpen) return 0;                             // security for some stupid main emus
+ if (spu.bSPUIsOpen) return 0;                         // security for some stupid main emus
 
  SetupSound();                                         // setup sound (before init!)
- SetupTimer();                                         // timer for feeding data
 
- bSPUIsOpen = 1;
spu.bSPUIsOpen = 1;
 
  return PSE_SPU_ERR_SUCCESS;
 }
@@ -1107,12 +1389,11 @@ long CALLBACK SPUopen(void)
 // SPUCLOSE: called before shutdown
 long CALLBACK SPUclose(void)
 {
- if (!bSPUIsOpen) return 0;                            // some security
+ if (!spu.bSPUIsOpen) return 0;                        // some security
 
bSPUIsOpen = 0;                                       // no more open
spu.bSPUIsOpen = 0;                                   // no more open
 
- RemoveTimer();                                        // no more feeding
- RemoveSound();                                        // no more sound handling
+ out_current->finish();                                // no more sound handling
 
  return 0;
 }
@@ -1122,6 +1403,9 @@ long CALLBACK SPUshutdown(void)
 {
  SPUclose();
  RemoveStreams();                                      // no more streaming
+ spu.bSpuInit=0;
+
+ exit_spu_thread();
 
  return 0;
 }
@@ -1158,12 +1442,17 @@ void CALLBACK SPUabout(void)
 // passes a callback that should be called on SPU-IRQ/cdda volume change
 void CALLBACK SPUregisterCallback(void (CALLBACK *callback)(void))
 {
- irqCallback = callback;
spu.irqCallback = callback;
 }
 
 void CALLBACK SPUregisterCDDAVolume(void (CALLBACK *CDDAVcallback)(unsigned short,unsigned short))
 {
- cddavCallback = CDDAVcallback;
+ spu.cddavCallback = CDDAVcallback;
+}
+
+void CALLBACK SPUregisterScheduleCb(void (CALLBACK *callback)(unsigned int))
+{
+ spu.scheduleCallback = callback;
 }
 
 // COMMON PLUGIN INFO FUNCS
@@ -1196,18 +1485,18 @@ void spu_get_debug_info(int *chans_out, int *run_chans, int *fmod_chans_out, int
 
  for(;ch<MAXCHAN;ch++)
  {
-  if (!(dwChannelOn & (1<<ch)))
+  if (!(spu.dwChannelOn & (1<<ch)))
    continue;
   if (s_chan[ch].bFMod == 2)
    fmod_chans |= 1 << ch;
   if (s_chan[ch].bNoise)
    noise_chans |= 1 << ch;
-  if((spuCtrl&CTRL_IRQ) && s_chan[ch].pCurr <= pSpuIrq && s_chan[ch].pLoop <= pSpuIrq)
+  if((spu.spuCtrl&CTRL_IRQ) && s_chan[ch].pCurr <= spu.pSpuIrq && s_chan[ch].pLoop <= spu.pSpuIrq)
    irq_chans |= 1 << ch;
  }
 
- *chans_out = dwChannelOn;
- *run_chans = ~dwChannelOn & ~dwChannelDead & irq_chans;
+ *chans_out = spu.dwChannelOn;
+ *run_chans = ~spu.dwChannelOn & ~spu.dwChannelDead & irq_chans;
  *fmod_chans_out = fmod_chans;
  *noise_chans_out = noise_chans;
 }