5 * This work is licensed under the terms of MAME license.
6 * See COPYING file in the top-level directory.
9 #include "../pico_int.h"
10 #include "../sound/ym2612.h"
12 extern unsigned char formatted_bram[4*0x10];
14 static unsigned int mcd_m68k_cycle_mult;
15 static unsigned int mcd_m68k_cycle_base;
16 static unsigned int mcd_s68k_cycle_base;
18 void (*PicoMCDopenTray)(void) = NULL;
19 void (*PicoMCDcloseTray)(void) = NULL;
22 PICO_INTERNAL void PicoInitMCD(void)
27 PICO_INTERNAL void PicoExitMCD(void)
31 PICO_INTERNAL void PicoPowerMCD(void)
33 SekCycleCntS68k = SekCycleAimS68k = 0;
35 int fmt_size = sizeof(formatted_bram);
36 memset(Pico_mcd->prg_ram, 0, sizeof(Pico_mcd->prg_ram));
37 memset(Pico_mcd->word_ram2M, 0, sizeof(Pico_mcd->word_ram2M));
38 memset(Pico_mcd->pcm_ram, 0, sizeof(Pico_mcd->pcm_ram));
39 memset(Pico_mcd->bram, 0, sizeof(Pico_mcd->bram));
40 memcpy(Pico_mcd->bram + sizeof(Pico_mcd->bram) - fmt_size,
41 formatted_bram, fmt_size);
42 memset(Pico_mcd->s68k_regs, 0, sizeof(Pico_mcd->s68k_regs));
43 memset(&Pico_mcd->pcm, 0, sizeof(Pico_mcd->pcm));
44 memset(&Pico_mcd->m, 0, sizeof(Pico_mcd->m));
49 // cold reset state (tested)
50 Pico_mcd->m.state_flags = PCD_ST_S68K_RST;
51 Pico_mcd->m.busreq = 2; // busreq on, s68k in reset
52 Pico_mcd->s68k_regs[3] = 1; // 2M word RAM mode, m68k access
53 memset(Pico_mcd->bios + 0x70, 0xff, 4);
56 void pcd_soft_reset(void)
58 elprintf(EL_CD, "cd: soft reset");
60 Pico_mcd->m.s68k_pend_ints = 0;
63 #ifdef _ASM_CD_MEMORY_C
64 //PicoMemResetCDdecode(1); // don't have to call this in 2M mode
67 memset(&Pico_mcd->s68k_regs[0x38], 0, 9);
68 Pico_mcd->s68k_regs[0x38+9] = 0x0f; // default checksum
70 pcd_event_schedule_s68k(PCD_EVENT_CDC, 12500000/75);
72 // TODO: test if register state/timers change
75 PICO_INTERNAL int PicoResetMCD(void)
77 // reset button doesn't affect MCD hardware
79 // use SRam.data for RAM cart
80 if (PicoOpt & POPT_EN_MCD_RAMCART) {
81 if (SRam.data == NULL)
82 SRam.data = calloc(1, 0x12000);
84 else if (SRam.data != NULL) {
88 SRam.start = SRam.end = 0; // unused
93 static __inline void SekRunS68k(unsigned int to)
98 if ((cyc_do = SekCycleAimS68k - SekCycleCntS68k) <= 0)
101 if (SekShouldInterrupt())
102 Pico_mcd->m.s68k_poll_a = 0;
104 SekCycleCntS68k += cyc_do;
105 #if defined(EMU_C68K)
106 PicoCpuCS68k.cycles = cyc_do;
107 CycloneRun(&PicoCpuCS68k);
108 SekCycleCntS68k -= PicoCpuCS68k.cycles;
109 #elif defined(EMU_M68K)
110 m68k_set_context(&PicoCpuMS68k);
111 SekCycleCntS68k += m68k_execute(cyc_do) - cyc_do;
112 m68k_set_context(&PicoCpuMM68k);
113 #elif defined(EMU_F68K)
114 g_m68kcontext = &PicoCpuFS68k;
115 SekCycleCntS68k += fm68k_emulate(cyc_do, 0) - cyc_do;
116 g_m68kcontext = &PicoCpuFM68k;
120 static void pcd_set_cycle_mult(void)
122 // ~1.63 for NTSC, ~1.645 for PAL
124 mcd_m68k_cycle_mult = ((12500000ull << 16) / (50*312*488));
126 mcd_m68k_cycle_mult = ((12500000ull << 16) / (60*262*488)) + 1;
129 unsigned int pcd_cycles_m68k_to_s68k(unsigned int c)
131 return (long long)c * mcd_m68k_cycle_mult >> 16;
135 static void pcd_cdc_event(unsigned int now)
140 /* check if a new CDD command has been processed */
141 if (!(Pico_mcd->s68k_regs[0x4b] & 0xf0))
143 /* reset CDD command wait flag */
144 Pico_mcd->s68k_regs[0x4b] = 0xf0;
146 if (Pico_mcd->s68k_regs[0x33] & PCDS_IEN4) {
147 elprintf(EL_INTS|EL_CD, "s68k: cdd irq 4");
152 pcd_event_schedule(now, PCD_EVENT_CDC, 12500000/75);
155 static void pcd_int3_timer_event(unsigned int now)
157 if (Pico_mcd->s68k_regs[0x33] & PCDS_IEN3) {
158 elprintf(EL_INTS|EL_CD, "s68k: timer irq 3");
162 if (Pico_mcd->s68k_regs[0x31] != 0)
163 pcd_event_schedule(now, PCD_EVENT_TIMER3,
164 Pico_mcd->s68k_regs[0x31] * 384);
167 static void pcd_dma_event(unsigned int now)
172 typedef void (event_cb)(unsigned int now);
174 /* times are in s68k (12.5MHz) cycles */
175 unsigned int pcd_event_times[PCD_EVENT_COUNT];
176 static unsigned int event_time_next;
177 static event_cb *pcd_event_cbs[PCD_EVENT_COUNT] = {
178 [PCD_EVENT_CDC] = pcd_cdc_event,
179 [PCD_EVENT_TIMER3] = pcd_int3_timer_event,
180 [PCD_EVENT_GFX] = gfx_update,
181 [PCD_EVENT_DMA] = pcd_dma_event,
184 void pcd_event_schedule(unsigned int now, enum pcd_event event, int after)
191 pcd_event_times[event] = 0;
197 elprintf(EL_CD, "cd: new event #%u %u->%u", event, now, when);
198 pcd_event_times[event] = when;
200 if (event_time_next == 0 || CYCLES_GT(event_time_next, when))
201 event_time_next = when;
204 void pcd_event_schedule_s68k(enum pcd_event event, int after)
206 if (SekCyclesLeftS68k > after)
207 SekEndRunS68k(after);
209 pcd_event_schedule(SekCyclesDoneS68k(), event, after);
212 static void pcd_run_events(unsigned int until)
214 int oldest, oldest_diff, time;
218 oldest = -1, oldest_diff = 0x7fffffff;
220 for (i = 0; i < PCD_EVENT_COUNT; i++) {
221 if (pcd_event_times[i]) {
222 diff = pcd_event_times[i] - until;
223 if (diff < oldest_diff) {
230 if (oldest_diff <= 0) {
231 time = pcd_event_times[oldest];
232 pcd_event_times[oldest] = 0;
233 elprintf(EL_CD, "cd: run event #%d %u", oldest, time);
234 pcd_event_cbs[oldest](time);
236 else if (oldest_diff < 0x7fffffff) {
237 event_time_next = pcd_event_times[oldest];
247 elprintf(EL_CD, "cd: next event #%d at %u",
248 oldest, event_time_next);
251 int pcd_sync_s68k(unsigned int m68k_target, int m68k_poll_sync)
253 #define now SekCycleCntS68k
254 unsigned int s68k_target;
257 target = m68k_target - mcd_m68k_cycle_base;
258 s68k_target = mcd_s68k_cycle_base +
259 ((unsigned long long)target * mcd_m68k_cycle_mult >> 16);
261 elprintf(EL_CD, "s68k sync to %u, %u->%u",
262 m68k_target, now, s68k_target);
264 if (Pico_mcd->m.busreq != 1) { /* busreq/reset */
265 SekCycleCntS68k = SekCycleAimS68k = s68k_target;
266 pcd_run_events(m68k_target);
270 while (CYCLES_GT(s68k_target, now)) {
271 if (event_time_next && CYCLES_GE(now, event_time_next))
274 target = s68k_target;
275 if (event_time_next && CYCLES_GT(target, event_time_next))
276 target = event_time_next;
279 if (m68k_poll_sync && Pico_mcd->m.m68k_poll_cnt == 0)
283 return s68k_target - now;
287 #define pcd_run_cpus_normal pcd_run_cpus
288 //#define pcd_run_cpus_lockstep pcd_run_cpus
290 static void SekSyncM68k(void);
292 void pcd_run_cpus_normal(int m68k_cycles)
294 SekCycleAim += m68k_cycles;
295 if (SekShouldInterrupt() || Pico_mcd->m.m68k_poll_cnt < 12)
296 Pico_mcd->m.m68k_poll_cnt = 0;
297 else if (Pico_mcd->m.m68k_poll_cnt >= 16) {
298 int s68k_left = pcd_sync_s68k(SekCycleAim, 1);
299 if (s68k_left <= 0) {
300 elprintf(EL_CDPOLL, "m68k poll [%02x] x%d @%06x",
301 Pico_mcd->m.m68k_poll_a, Pico_mcd->m.m68k_poll_cnt, SekPc);
302 SekCycleCnt = SekCycleAim;
305 SekCycleCnt = SekCycleAim - (s68k_left * 40220 >> 16);
311 void pcd_run_cpus_lockstep(int m68k_cycles)
313 unsigned int target = SekCycleAim + m68k_cycles;
317 pcd_sync_s68k(SekCycleAim, 0);
318 } while (CYCLES_GT(target, SekCycleAim));
320 SekCycleAim = target;
324 #define CPUS_RUN(m68k_cycles) \
325 pcd_run_cpus(m68k_cycles)
327 #include "../pico_cmn.c"
330 void pcd_prepare_frame(void)
332 pcd_set_cycle_mult();
334 // need this because we can't have direct mapping between
335 // master<->slave cycle counters because of overflows
336 mcd_m68k_cycle_base = SekCycleAim;
337 mcd_s68k_cycle_base = SekCycleAimS68k;
340 PICO_INTERNAL void PicoFrameMCD(void)
348 void pcd_state_loaded(void)
353 pcd_set_cycle_mult();
354 pcd_state_loaded_mem();
356 memset(Pico_mcd->pcm_mixbuf, 0, sizeof(Pico_mcd->pcm_mixbuf));
357 Pico_mcd->pcm_mixbuf_dirty = 0;
358 Pico_mcd->pcm_mixpos = 0;
359 Pico_mcd->pcm_regs_dirty = 1;
362 cycles = pcd_cycles_m68k_to_s68k(SekCycleAim);
363 diff = cycles - SekCycleAimS68k;
364 if (diff < -1000 || diff > 1000) {
365 SekCycleCntS68k = SekCycleAimS68k = cycles;
367 if (pcd_event_times[PCD_EVENT_CDC] == 0) {
368 pcd_event_schedule(SekCycleAimS68k, PCD_EVENT_CDC, 12500000/75);
370 if (Pico_mcd->s68k_regs[0x31])
371 pcd_event_schedule(SekCycleAimS68k, PCD_EVENT_TIMER3,
372 Pico_mcd->s68k_regs[0x31] * 384);
375 diff = cycles - Pico_mcd->pcm.update_cycles;
376 if ((unsigned int)diff > 12500000/50)
377 Pico_mcd->pcm.update_cycles = cycles;
381 pcd_run_events(SekCycleCntS68k);
384 // vim:shiftwidth=2:ts=2:expandtab