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)
35 SekCycleCntS68k = SekCycleAimS68k = 0;
37 fmt_size = sizeof(formatted_bram);
38 memset(Pico_mcd->prg_ram, 0, sizeof(Pico_mcd->prg_ram));
39 memset(Pico_mcd->word_ram2M, 0, sizeof(Pico_mcd->word_ram2M));
40 memset(Pico_mcd->pcm_ram, 0, sizeof(Pico_mcd->pcm_ram));
41 memset(Pico_mcd->bram, 0, sizeof(Pico_mcd->bram));
42 memcpy(Pico_mcd->bram + sizeof(Pico_mcd->bram) - fmt_size,
43 formatted_bram, fmt_size);
44 memset(Pico_mcd->s68k_regs, 0, sizeof(Pico_mcd->s68k_regs));
45 memset(&Pico_mcd->pcm, 0, sizeof(Pico_mcd->pcm));
46 memset(&Pico_mcd->m, 0, sizeof(Pico_mcd->m));
51 // cold reset state (tested)
52 Pico_mcd->m.state_flags = PCD_ST_S68K_RST;
53 Pico_mcd->m.busreq = 2; // busreq on, s68k in reset
54 Pico_mcd->s68k_regs[3] = 1; // 2M word RAM mode, m68k access
55 memset(Pico_mcd->bios + 0x70, 0xff, 4);
58 void pcd_soft_reset(void)
60 elprintf(EL_CD, "cd: soft reset");
62 Pico_mcd->m.s68k_pend_ints = 0;
65 #ifdef _ASM_CD_MEMORY_C
66 //PicoMemResetCDdecode(1); // don't have to call this in 2M mode
69 memset(&Pico_mcd->s68k_regs[0x38], 0, 9);
70 Pico_mcd->s68k_regs[0x38+9] = 0x0f; // default checksum
72 pcd_event_schedule_s68k(PCD_EVENT_CDC, 12500000/75);
74 // TODO: test if register state/timers change
77 PICO_INTERNAL int PicoResetMCD(void)
79 // reset button doesn't affect MCD hardware
81 // use Pico.sv.data for RAM cart
82 if (PicoOpt & POPT_EN_MCD_RAMCART) {
83 if (Pico.sv.data == NULL)
84 Pico.sv.data = calloc(1, 0x12000);
86 else if (Pico.sv.data != NULL) {
90 Pico.sv.start = Pico.sv.end = 0; // unused
95 static void SekRunM68kOnce(void)
98 pevt_log_m68k_o(EVT_RUN_START);
100 if ((cyc_do = Pico.t.m68c_aim - Pico.t.m68c_cnt) > 0) {
101 Pico.t.m68c_cnt += cyc_do;
103 #if defined(EMU_C68K)
104 PicoCpuCM68k.cycles = cyc_do;
105 CycloneRun(&PicoCpuCM68k);
106 Pico.t.m68c_cnt -= PicoCpuCM68k.cycles;
107 #elif defined(EMU_M68K)
108 Pico.t.m68c_cnt += m68k_execute(cyc_do) - cyc_do;
109 #elif defined(EMU_F68K)
110 Pico.t.m68c_cnt += fm68k_emulate(cyc_do, 0) - cyc_do;
117 pevt_log_m68k_o(EVT_RUN_END);
120 static void SekRunS68k(unsigned int to)
124 SekCycleAimS68k = to;
125 if ((cyc_do = SekCycleAimS68k - SekCycleCntS68k) <= 0)
128 if (SekShouldInterrupt())
129 Pico_mcd->m.s68k_poll_a = 0;
131 SekCycleCntS68k += cyc_do;
132 #if defined(EMU_C68K)
133 PicoCpuCS68k.cycles = cyc_do;
134 CycloneRun(&PicoCpuCS68k);
135 SekCycleCntS68k -= PicoCpuCS68k.cycles;
136 #elif defined(EMU_M68K)
137 m68k_set_context(&PicoCpuMS68k);
138 SekCycleCntS68k += m68k_execute(cyc_do) - cyc_do;
139 m68k_set_context(&PicoCpuMM68k);
140 #elif defined(EMU_F68K)
141 g_m68kcontext = &PicoCpuFS68k;
142 SekCycleCntS68k += fm68k_emulate(cyc_do, 0) - cyc_do;
143 g_m68kcontext = &PicoCpuFM68k;
147 static void pcd_set_cycle_mult(void)
149 // ~1.63 for NTSC, ~1.645 for PAL
151 mcd_m68k_cycle_mult = ((12500000ull << 16) / (50*313*488));
153 mcd_m68k_cycle_mult = ((12500000ull << 16) / (60*262*488)) + 1;
156 unsigned int pcd_cycles_m68k_to_s68k(unsigned int c)
158 return (long long)c * mcd_m68k_cycle_mult >> 16;
162 static void pcd_cdc_event(unsigned int now)
167 /* check if a new CDD command has been processed */
168 if (!(Pico_mcd->s68k_regs[0x4b] & 0xf0))
170 /* reset CDD command wait flag */
171 Pico_mcd->s68k_regs[0x4b] = 0xf0;
173 if (Pico_mcd->s68k_regs[0x33] & PCDS_IEN4) {
174 elprintf(EL_INTS|EL_CD, "s68k: cdd irq 4");
179 pcd_event_schedule(now, PCD_EVENT_CDC, 12500000/75);
182 static void pcd_int3_timer_event(unsigned int now)
184 if (Pico_mcd->s68k_regs[0x33] & PCDS_IEN3) {
185 elprintf(EL_INTS|EL_CD, "s68k: timer irq 3");
189 if (Pico_mcd->s68k_regs[0x31] != 0)
190 pcd_event_schedule(now, PCD_EVENT_TIMER3,
191 Pico_mcd->s68k_regs[0x31] * 384);
194 static void pcd_dma_event(unsigned int now)
199 typedef void (event_cb)(unsigned int now);
201 /* times are in s68k (12.5MHz) cycles */
202 unsigned int pcd_event_times[PCD_EVENT_COUNT];
203 static unsigned int event_time_next;
204 static event_cb *pcd_event_cbs[PCD_EVENT_COUNT] = {
205 pcd_cdc_event, // PCD_EVENT_CDC
206 pcd_int3_timer_event, // PCD_EVENT_TIMER3
207 gfx_update, // PCD_EVENT_GFX
208 pcd_dma_event, // PCD_EVENT_DMA
211 void pcd_event_schedule(unsigned int now, enum pcd_event event, int after)
218 pcd_event_times[event] = 0;
224 elprintf(EL_CD, "cd: new event #%u %u->%u", event, now, when);
225 pcd_event_times[event] = when;
227 if (event_time_next == 0 || CYCLES_GT(event_time_next, when))
228 event_time_next = when;
231 void pcd_event_schedule_s68k(enum pcd_event event, int after)
233 if (SekCyclesLeftS68k > after)
234 SekEndRunS68k(after);
236 pcd_event_schedule(SekCyclesDoneS68k(), event, after);
239 static void pcd_run_events(unsigned int until)
241 int oldest, oldest_diff, time;
245 oldest = -1, oldest_diff = 0x7fffffff;
247 for (i = 0; i < PCD_EVENT_COUNT; i++) {
248 if (pcd_event_times[i]) {
249 diff = pcd_event_times[i] - until;
250 if (diff < oldest_diff) {
257 if (oldest_diff <= 0) {
258 time = pcd_event_times[oldest];
259 pcd_event_times[oldest] = 0;
260 elprintf(EL_CD, "cd: run event #%d %u", oldest, time);
261 pcd_event_cbs[oldest](time);
263 else if (oldest_diff < 0x7fffffff) {
264 event_time_next = pcd_event_times[oldest];
274 elprintf(EL_CD, "cd: next event #%d at %u",
275 oldest, event_time_next);
278 int pcd_sync_s68k(unsigned int m68k_target, int m68k_poll_sync)
280 #define now SekCycleCntS68k
281 unsigned int s68k_target;
284 target = m68k_target - mcd_m68k_cycle_base;
285 s68k_target = mcd_s68k_cycle_base +
286 ((unsigned long long)target * mcd_m68k_cycle_mult >> 16);
288 elprintf(EL_CD, "s68k sync to %u, %u->%u",
289 m68k_target, now, s68k_target);
291 if (Pico_mcd->m.busreq != 1) { /* busreq/reset */
292 SekCycleCntS68k = SekCycleAimS68k = s68k_target;
293 pcd_run_events(m68k_target);
297 while (CYCLES_GT(s68k_target, now)) {
298 if (event_time_next && CYCLES_GE(now, event_time_next))
301 target = s68k_target;
302 if (event_time_next && CYCLES_GT(target, event_time_next))
303 target = event_time_next;
306 if (m68k_poll_sync && Pico_mcd->m.m68k_poll_cnt == 0)
310 return s68k_target - now;
314 #define pcd_run_cpus_normal pcd_run_cpus
315 //#define pcd_run_cpus_lockstep pcd_run_cpus
317 static void SekSyncM68k(void);
319 void pcd_run_cpus_normal(int m68k_cycles)
321 Pico.t.m68c_aim += m68k_cycles;
322 if (SekShouldInterrupt() || Pico_mcd->m.m68k_poll_cnt < 12)
323 Pico_mcd->m.m68k_poll_cnt = 0;
324 else if (Pico_mcd->m.m68k_poll_cnt >= 16) {
325 int s68k_left = pcd_sync_s68k(Pico.t.m68c_aim, 1);
326 if (s68k_left <= 0) {
327 elprintf(EL_CDPOLL, "m68k poll [%02x] x%d @%06x",
328 Pico_mcd->m.m68k_poll_a, Pico_mcd->m.m68k_poll_cnt, SekPc);
329 Pico.t.m68c_cnt = Pico.t.m68c_aim;
332 Pico.t.m68c_cnt = Pico.t.m68c_aim - (s68k_left * 40220 >> 16);
335 while (CYCLES_GT(Pico.t.m68c_aim, Pico.t.m68c_cnt)) {
337 if (Pico_mcd->m.need_sync) {
338 Pico_mcd->m.need_sync = 0;
339 pcd_sync_s68k(Pico.t.m68c_cnt, 0);
344 void pcd_run_cpus_lockstep(int m68k_cycles)
346 unsigned int target = Pico.t.m68c_aim + m68k_cycles;
348 Pico.t.m68c_aim += 8;
350 pcd_sync_s68k(Pico.t.m68c_aim, 0);
351 } while (CYCLES_GT(target, Pico.t.m68c_aim));
353 Pico.t.m68c_aim = target;
357 #define CPUS_RUN(m68k_cycles) \
358 pcd_run_cpus(m68k_cycles)
360 #include "../pico_cmn.c"
363 void pcd_prepare_frame(void)
365 pcd_set_cycle_mult();
367 // need this because we can't have direct mapping between
368 // master<->slave cycle counters because of overflows
369 mcd_m68k_cycle_base = Pico.t.m68c_aim;
370 mcd_s68k_cycle_base = SekCycleAimS68k;
373 PICO_INTERNAL void PicoFrameMCD(void)
381 void pcd_state_loaded(void)
386 pcd_set_cycle_mult();
387 pcd_state_loaded_mem();
389 memset(Pico_mcd->pcm_mixbuf, 0, sizeof(Pico_mcd->pcm_mixbuf));
390 Pico_mcd->pcm_mixbuf_dirty = 0;
391 Pico_mcd->pcm_mixpos = 0;
392 Pico_mcd->pcm_regs_dirty = 1;
395 cycles = pcd_cycles_m68k_to_s68k(Pico.t.m68c_aim);
396 diff = cycles - SekCycleAimS68k;
397 if (diff < -1000 || diff > 1000) {
398 SekCycleCntS68k = SekCycleAimS68k = cycles;
400 if (pcd_event_times[PCD_EVENT_CDC] == 0) {
401 pcd_event_schedule(SekCycleAimS68k, PCD_EVENT_CDC, 12500000/75);
403 if (Pico_mcd->s68k_regs[0x31])
404 pcd_event_schedule(SekCycleAimS68k, PCD_EVENT_TIMER3,
405 Pico_mcd->s68k_regs[0x31] * 384);
408 diff = cycles - Pico_mcd->pcm.update_cycles;
409 if ((unsigned int)diff > 12500000/50)
410 Pico_mcd->pcm.update_cycles = cycles;
414 pcd_run_events(SekCycleCntS68k);
417 // vim:shiftwidth=2:ts=2:expandtab