psxcounters: try to eliminate another source of audio drift
[pcsx_rearmed.git] / libpcsxcore / psxcounters.c
1 /***************************************************************************
2  *   Copyright (C) 2010 by Blade_Arma                                      *
3  *                                                                         *
4  *   This program is free software; you can redistribute it and/or modify  *
5  *   it under the terms of the GNU General Public License as published by  *
6  *   the Free Software Foundation; either version 2 of the License, or     *
7  *   (at your option) any later version.                                   *
8  *                                                                         *
9  *   This program is distributed in the hope that it will be useful,       *
10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
12  *   GNU General Public License for more details.                          *
13  *                                                                         *
14  *   You should have received a copy of the GNU General Public License     *
15  *   along with this program; if not, write to the                         *
16  *   Free Software Foundation, Inc.,                                       *
17  *   51 Franklin Street, Fifth Floor, Boston, MA 02111-1307 USA.           *
18  ***************************************************************************/
19
20 /*
21  * Internal PSX counters.
22  */
23
24 #include "psxcounters.h"
25 #include "gpu.h"
26 //#include "debug.h"
27 #define DebugVSync()
28
29 /******************************************************************************/
30
31 enum
32 {
33     Rc0Gate           = 0x0001, // 0    not implemented
34     Rc1Gate           = 0x0001, // 0    not implemented
35     Rc2Disable        = 0x0001, // 0    partially implemented
36     RcUnknown1        = 0x0002, // 1    ?
37     RcUnknown2        = 0x0004, // 2    ?
38     RcCountToTarget   = 0x0008, // 3
39     RcIrqOnTarget     = 0x0010, // 4
40     RcIrqOnOverflow   = 0x0020, // 5
41     RcIrqRegenerate   = 0x0040, // 6
42     RcUnknown7        = 0x0080, // 7    ?
43     Rc0PixelClock     = 0x0100, // 8    fake implementation
44     Rc1HSyncClock     = 0x0100, // 8
45     Rc2Unknown8       = 0x0100, // 8    ?
46     Rc0Unknown9       = 0x0200, // 9    ?
47     Rc1Unknown9       = 0x0200, // 9    ?
48     Rc2OneEighthClock = 0x0200, // 9
49     RcUnknown10       = 0x0400, // 10   ?
50     RcCountEqTarget   = 0x0800, // 11
51     RcOverflow        = 0x1000, // 12
52     RcUnknown13       = 0x2000, // 13   ? (always zero)
53     RcUnknown14       = 0x4000, // 14   ? (always zero)
54     RcUnknown15       = 0x8000, // 15   ? (always zero)
55 };
56
57 #define CounterQuantity           ( 4 )
58 //static const u32 CounterQuantity  = 4;
59
60 static const u32 CountToOverflow  = 0;
61 static const u32 CountToTarget    = 1;
62
63 static const u32 FrameRate[]      = { 60, 50 };
64 static const u32 HSyncTotal[]     = { 263, 314 }; // actually one more on odd lines for PAL
65 #define VBlankStart 240
66
67 #define VERBOSE_LEVEL 0
68
69 /******************************************************************************/
70 #ifdef DRC_DISABLE
71 Rcnt rcnts[ CounterQuantity ];
72 #endif
73 u32 hSyncCount = 0;
74 u32 frame_counter = 0;
75 static u32 hsync_steps = 0;
76
77 u32 psxNextCounter = 0, psxNextsCounter = 0;
78
79 /******************************************************************************/
80
81 static inline
82 void setIrq( u32 irq )
83 {
84     psxHu32ref(0x1070) |= SWAPu32(irq);
85 }
86
87 static
88 void verboseLog( u32 level, const char *str, ... )
89 {
90 #if VERBOSE_LEVEL > 0
91     if( level <= VERBOSE_LEVEL )
92     {
93         va_list va;
94         char buf[ 4096 ];
95
96         va_start( va, str );
97         vsprintf( buf, str, va );
98         va_end( va );
99
100         printf( "%s", buf );
101         fflush( stdout );
102     }
103 #endif
104 }
105
106 /******************************************************************************/
107
108 static inline
109 void _psxRcntWcount( u32 index, u32 value )
110 {
111     if( value > 0xffff )
112     {
113         verboseLog( 1, "[RCNT %i] wcount > 0xffff: %x\n", index, value );
114         value &= 0xffff;
115     }
116
117     rcnts[index].cycleStart  = psxRegs.cycle;
118     rcnts[index].cycleStart -= value * rcnts[index].rate;
119
120     // TODO: <=.
121     if( value < rcnts[index].target )
122     {
123         rcnts[index].cycle = rcnts[index].target * rcnts[index].rate;
124         rcnts[index].counterState = CountToTarget;
125     }
126     else
127     {
128         rcnts[index].cycle = 0x10000 * rcnts[index].rate;
129         rcnts[index].counterState = CountToOverflow;
130     }
131 }
132
133 static inline
134 u32 _psxRcntRcount( u32 index )
135 {
136     u32 count;
137
138     count  = psxRegs.cycle;
139     count -= rcnts[index].cycleStart;
140     if (rcnts[index].rate > 1)
141         count /= rcnts[index].rate;
142
143     if( count > 0x10000 )
144     {
145         verboseLog( 1, "[RCNT %i] rcount > 0x10000: %x\n", index, count );
146     }
147     count &= 0xffff;
148
149     return count;
150 }
151
152 static
153 void _psxRcntWmode( u32 index, u32 value )
154 {
155     rcnts[index].mode = value;
156
157     switch( index )
158     {
159         case 0:
160             if( value & Rc0PixelClock )
161             {
162                 rcnts[index].rate = 5;
163             }
164             else
165             {
166                 rcnts[index].rate = 1;
167             }
168         break;
169         case 1:
170             if( value & Rc1HSyncClock )
171             {
172                 rcnts[index].rate = (PSXCLK / (FrameRate[Config.PsxType] * HSyncTotal[Config.PsxType]));
173             }
174             else
175             {
176                 rcnts[index].rate = 1;
177             }
178         break;
179         case 2:
180             if( value & Rc2OneEighthClock )
181             {
182                 rcnts[index].rate = 8;
183             }
184             else
185             {
186                 rcnts[index].rate = 1;
187             }
188
189             // TODO: wcount must work.
190             if( value & Rc2Disable )
191             {
192                 rcnts[index].rate = 0xffffffff;
193             }
194         break;
195     }
196 }
197
198 /******************************************************************************/
199
200 static
201 void psxRcntSet()
202 {
203     s32 countToUpdate;
204     u32 i;
205
206     psxNextsCounter = psxRegs.cycle;
207     psxNextCounter  = 0x7fffffff;
208
209     for( i = 0; i < CounterQuantity; ++i )
210     {
211         countToUpdate = rcnts[i].cycle - (psxNextsCounter - rcnts[i].cycleStart);
212
213         if( countToUpdate < 0 )
214         {
215             psxNextCounter = 0;
216             break;
217         }
218
219         if( countToUpdate < (s32)psxNextCounter )
220         {
221             psxNextCounter = countToUpdate;
222         }
223     }
224
225     psxRegs.interrupt |= (1 << PSXINT_RCNT);
226     new_dyna_set_event(PSXINT_RCNT, psxNextCounter);
227 }
228
229 /******************************************************************************/
230
231 static
232 void psxRcntReset( u32 index )
233 {
234     u32 rcycles;
235
236     rcnts[index].mode |= RcUnknown10;
237
238     if( rcnts[index].counterState == CountToTarget )
239     {
240         rcycles = psxRegs.cycle - rcnts[index].cycleStart;
241         if( rcnts[index].mode & RcCountToTarget )
242         {
243             rcycles -= rcnts[index].target * rcnts[index].rate;
244             rcnts[index].cycleStart = psxRegs.cycle - rcycles;
245         }
246         else
247         {
248             rcnts[index].cycle = 0x10000 * rcnts[index].rate;
249             rcnts[index].counterState = CountToOverflow;
250         }
251
252         if( rcnts[index].mode & RcIrqOnTarget )
253         {
254             if( (rcnts[index].mode & RcIrqRegenerate) || (!rcnts[index].irqState) )
255             {
256                 verboseLog( 3, "[RCNT %i] irq\n", index );
257                 setIrq( rcnts[index].irq );
258                 rcnts[index].irqState = 1;
259             }
260         }
261
262         rcnts[index].mode |= RcCountEqTarget;
263
264         if( rcycles < 0x10000 * rcnts[index].rate )
265             return;
266     }
267
268     if( rcnts[index].counterState == CountToOverflow )
269     {
270         rcycles = psxRegs.cycle - rcnts[index].cycleStart;
271         rcycles -= 0x10000 * rcnts[index].rate;
272
273         rcnts[index].cycleStart = psxRegs.cycle - rcycles;
274
275         if( rcycles < rcnts[index].target * rcnts[index].rate )
276         {
277             rcnts[index].cycle = rcnts[index].target * rcnts[index].rate;
278             rcnts[index].counterState = CountToTarget;
279         }
280
281         if( rcnts[index].mode & RcIrqOnOverflow )
282         {
283             if( (rcnts[index].mode & RcIrqRegenerate) || (!rcnts[index].irqState) )
284             {
285                 verboseLog( 3, "[RCNT %i] irq\n", index );
286                 setIrq( rcnts[index].irq );
287                 rcnts[index].irqState = 1;
288             }
289         }
290
291         rcnts[index].mode |= RcOverflow;
292     }
293 }
294
295 static void scheduleRcntBase(void)
296 {
297     // Schedule next call, in hsyncs
298     if (hSyncCount < VBlankStart)
299         hsync_steps = VBlankStart - hSyncCount;
300     else
301         hsync_steps = HSyncTotal[Config.PsxType] - hSyncCount;
302
303     if (hSyncCount + hsync_steps == HSyncTotal[Config.PsxType])
304     {
305         rcnts[3].cycle = Config.PsxType ? PSXCLK / 50 : PSXCLK / 60;
306     }
307     else
308     {
309         // clk / 50 / 314 ~= 2157.25
310         // clk / 60 / 263 ~= 2146.31
311         u32 mult = Config.PsxType ? 8836089 : 8791293;
312         rcnts[3].cycle = hsync_steps * mult >> 12;
313     }
314 }
315
316 void psxRcntUpdate()
317 {
318     u32 cycle;
319
320     cycle = psxRegs.cycle;
321
322     // rcnt 0.
323     while( cycle - rcnts[0].cycleStart >= rcnts[0].cycle )
324     {
325         psxRcntReset( 0 );
326     }
327
328     // rcnt 1.
329     while( cycle - rcnts[1].cycleStart >= rcnts[1].cycle )
330     {
331         psxRcntReset( 1 );
332     }
333
334     // rcnt 2.
335     while( cycle - rcnts[2].cycleStart >= rcnts[2].cycle )
336     {
337         psxRcntReset( 2 );
338     }
339
340     // rcnt base.
341     if( cycle - rcnts[3].cycleStart >= rcnts[3].cycle )
342     {
343         hSyncCount += hsync_steps;
344
345         // VSync irq.
346         if( hSyncCount == VBlankStart )
347         {
348             HW_GPU_STATUS &= SWAP32(~PSXGPU_LCF);
349             GPU_vBlank( 1, 0 );
350             setIrq( 0x01 );
351
352             EmuUpdate();
353             GPU_updateLace();
354
355             if( SPU_async )
356             {
357                 SPU_async( cycle, 1 );
358             }
359         }
360         
361         // Update lace. (with InuYasha fix)
362         if( hSyncCount >= (Config.VSyncWA ? HSyncTotal[Config.PsxType] / BIAS : HSyncTotal[Config.PsxType]) )
363         {
364             rcnts[3].cycleStart += Config.PsxType ? PSXCLK / 50 : PSXCLK / 60;
365             hSyncCount = 0;
366             frame_counter++;
367
368             gpuSyncPluginSR();
369             if ((HW_GPU_STATUS & SWAP32(PSXGPU_ILACE_BITS)) == SWAP32(PSXGPU_ILACE_BITS))
370                 HW_GPU_STATUS |= SWAP32(frame_counter << 31);
371             GPU_vBlank(0, SWAP32(HW_GPU_STATUS) >> 31);
372         }
373
374         scheduleRcntBase();
375     }
376
377     psxRcntSet();
378
379 #ifndef NDEBUG
380     DebugVSync();
381 #endif
382 }
383
384 /******************************************************************************/
385
386 void psxRcntWcount( u32 index, u32 value )
387 {
388     verboseLog( 2, "[RCNT %i] wcount: %x\n", index, value );
389
390     _psxRcntWcount( index, value );
391     psxRcntSet();
392 }
393
394 void psxRcntWmode( u32 index, u32 value )
395 {
396     verboseLog( 1, "[RCNT %i] wmode: %x\n", index, value );
397
398     _psxRcntWmode( index, value );
399     _psxRcntWcount( index, 0 );
400
401     rcnts[index].irqState = 0;
402     psxRcntSet();
403 }
404
405 void psxRcntWtarget( u32 index, u32 value )
406 {
407     verboseLog( 1, "[RCNT %i] wtarget: %x\n", index, value );
408
409     rcnts[index].target = value;
410
411     _psxRcntWcount( index, _psxRcntRcount( index ) );
412     psxRcntSet();
413 }
414
415 /******************************************************************************/
416
417 u32 psxRcntRcount( u32 index )
418 {
419     u32 count;
420
421     count = _psxRcntRcount( index );
422
423     // Parasite Eve 2 fix.
424     if( Config.RCntFix )
425     {
426         if( index == 2 )
427         {
428             if( rcnts[index].counterState == CountToTarget )
429             {
430                 count /= BIAS;
431             }
432         }
433     }
434
435     verboseLog( 2, "[RCNT %i] rcount: %x\n", index, count );
436
437     return count;
438 }
439
440 u32 psxRcntRmode( u32 index )
441 {
442     u16 mode;
443
444     mode = rcnts[index].mode;
445     rcnts[index].mode &= 0xe7ff;
446
447     verboseLog( 2, "[RCNT %i] rmode: %x\n", index, mode );
448
449     return mode;
450 }
451
452 u32 psxRcntRtarget( u32 index )
453 {
454     verboseLog( 2, "[RCNT %i] rtarget: %x\n", index, rcnts[index].target );
455
456     return rcnts[index].target;
457 }
458
459 /******************************************************************************/
460
461 void psxRcntInit()
462 {
463     s32 i;
464
465     // rcnt 0.
466     rcnts[0].rate   = 1;
467     rcnts[0].irq    = 0x10;
468
469     // rcnt 1.
470     rcnts[1].rate   = 1;
471     rcnts[1].irq    = 0x20;
472
473     // rcnt 2.
474     rcnts[2].rate   = 1;
475     rcnts[2].irq    = 0x40;
476
477     // rcnt base.
478     rcnts[3].rate   = 1;
479     rcnts[3].mode   = RcCountToTarget;
480     rcnts[3].target = (PSXCLK / (FrameRate[Config.PsxType] * HSyncTotal[Config.PsxType]));
481
482     for( i = 0; i < CounterQuantity; ++i )
483     {
484         _psxRcntWcount( i, 0 );
485     }
486
487     hSyncCount = 0;
488     hsync_steps = 1;
489
490     psxRcntSet();
491 }
492
493 /******************************************************************************/
494
495 s32 psxRcntFreeze( void *f, s32 Mode )
496 {
497     u32 spuSyncCount = 0;
498     u32 count;
499     s32 i;
500
501     gzfreeze( &rcnts, sizeof(Rcnt) * CounterQuantity );
502     gzfreeze( &hSyncCount, sizeof(hSyncCount) );
503     gzfreeze( &spuSyncCount, sizeof(spuSyncCount) );
504     gzfreeze( &psxNextCounter, sizeof(psxNextCounter) );
505     gzfreeze( &psxNextsCounter, sizeof(psxNextsCounter) );
506
507     if (Mode == 0)
508     {
509         // don't trust things from a savestate
510         rcnts[3].rate = 1;
511         for( i = 0; i < CounterQuantity; ++i )
512         {
513             _psxRcntWmode( i, rcnts[i].mode );
514             count = (psxRegs.cycle - rcnts[i].cycleStart) / rcnts[i].rate;
515             _psxRcntWcount( i, count );
516         }
517         scheduleRcntBase();
518         psxRcntSet();
519     }
520
521     return 0;
522 }
523
524 /******************************************************************************/
525 // vim:ts=4:shiftwidth=4:expandtab