5 * This work is licensed under the terms of MAME license.
6 * See COPYING file in the top-level directory.
8 #include "../pico_int.h"
10 static int pwm_cycle_counter;
11 static int pwm_cycles;
15 static int pwm_smp_cnt;
16 static int pwm_smp_expect;
18 static int timer_cycles[2];
19 static int timer_tick_cycles[2];
21 // timers. This includes PWM timer in 32x and internal SH2 timers
22 void p32x_timers_recalc(void)
24 int cycles = Pico32x.regs[0x32 / 2];
27 cycles = (cycles - 1) & 0x0fff;
29 elprintf(EL_32X|EL_PWM|EL_ANOMALY, "pwm: low cycle value: %d", cycles + 1);
33 pwm_mult = 0x10000 / cycles;
36 for (i = 0; i < 2; i++) {
37 tmp = PREG8(Pico32xMem->sh2_peri_regs[i], 0x80) & 7;
38 // Sclk cycles per timer tick
43 timer_tick_cycles[i] = cycles;
44 elprintf(EL_32X, "WDT cycles[%d] = %d", i, cycles);
48 // PWM irq for every tm samples
49 void p32x_timers_do(unsigned int cycles)
55 pwm_cycle_counter += cycles;
56 while (pwm_cycle_counter > pwm_cycles) {
57 pwm_cycle_counter -= pwm_cycles;
62 for (i = 0; i < 2; i++) {
63 void *pregs = Pico32xMem->sh2_peri_regs[i];
64 if (PREG8(pregs, 0x80) & 0x20) { // TME
65 timer_cycles[i] += cycles;
66 cnt = PREG8(pregs, 0x81);
67 while (timer_cycles[i] >= timer_tick_cycles[i]) {
68 timer_cycles[i] -= timer_tick_cycles[i];
72 int level = PREG8(pregs, 0xe3) >> 4;
73 int vector = PREG8(pregs, 0xe4) & 0x7f;
74 elprintf(EL_32X, "%csh2 WDT irq (%d, %d)",
75 i ? 's' : 'm', level, vector);
76 sh2_internal_irq(&sh2s[i], level, vector);
79 PREG8(pregs, 0x81) = cnt;
84 void p32x_pwm_schedule(unsigned int now)
88 if (Pico32x.emu_flags & P32XF_PWM_PEND)
89 return; // already scheduled
90 if (Pico32x.sh2irqs & P32XI_PWM)
91 return; // previous not acked
92 if (!((Pico32x.sh2irq_mask[0] | Pico32x.sh2irq_mask[1]) & 1))
93 return; // masked by everyone
95 tm = (Pico32x.regs[0x30 / 2] & 0x0f00) >> 8;
96 tm = ((tm - 1) & 0x0f) + 1;
97 p32x_event_schedule(P32X_EVENT_PWM, now, pwm_cycles * tm / 3);
98 Pico32x.emu_flags |= P32XF_PWM_PEND;
101 unsigned int p32x_pwm_read16(unsigned int a)
110 return Pico32x.regs[(0x30 + a) / 2];
115 diff = pwm_smp_cnt - pwm_smp_expect;
116 elprintf(EL_PWM, "pwm: read status: ptr %d/%d %d",
117 pwm_smp_cnt, pwm_smp_expect, diff);
128 void p32x_pwm_write16(unsigned int a, unsigned int d)
131 if (a == 0) // control
132 Pico32x.regs[0x30 / 2] = d;
133 else if (a == 2) { // cycle
134 Pico32x.regs[0x32 / 2] = d & 0x0fff;
135 p32x_timers_recalc();
136 Pico32x.pwm_irq_sample_cnt = 0; // resets?
142 d = (d - pwm_cycles / 2) * pwm_mult;
145 Pico32xMem->pwm[pwm_ptr * 2] = d;
146 else if (a == 6) // R ch
147 Pico32xMem->pwm[pwm_ptr * 2 + 1] = d;
149 Pico32xMem->pwm[pwm_ptr * 2] = Pico32xMem->pwm[pwm_ptr * 2 + 1] = d;
151 if (a >= 6) { // R or MONO
153 pwm_ptr = (pwm_ptr + 1) & (PWM_BUFF_LEN - 1);
154 elprintf(EL_PWM, "pwm: smp_cnt %d, ptr %d, smp %x",
155 pwm_smp_cnt, pwm_ptr, d);
160 void p32x_pwm_update(int *buf32, int length, int stereo)
166 if (pwm_ptr <= 16) // at least some samples..
169 step = (pwm_ptr << 16) / length; // FIXME: division..
170 pwmb = Pico32xMem->pwm;
174 while (length-- > 0) {
179 pwmb += (p >> 16) * 2;
185 while (length-- > 0) {
189 pwmb += (p >> 16) * 2;
194 elprintf(EL_PWM, "pwm_update: pwm_ptr %d, len %d, step %04x, done %d",
195 pwm_ptr, length, step, (pwmb - Pico32xMem->pwm) / 2);
200 // vim:shiftwidth=2:ts=2:expandtab