Files
86Box-fork/src/pit.c

631 lines
22 KiB
C

/* Copyright holders: Sarah Walker, Tenshi
see COPYING for more details
*/
/*IBM AT -
Write B0
Write aa55
Expects aa55 back*/
#include <string.h>
#include "ibm.h"
#include "cpu.h"
#include "dma.h"
#include "io.h"
#include "pic.h"
#include "pit.h"
#include "timer.h"
#include "video.h"
#include "model.h"
/*B0 to 40, two writes to 43, then two reads - value does not change!*/
/*B4 to 40, two writes to 43, then two reads - value _does_ change!*/
//Tyrian writes 4300 or 17512
int displine;
double PITCONST;
float cpuclock;
float isa_timing, bus_timing;
int firsttime=1;
void setpitclock(float clock)
{
// printf("PIT clock %f\n",clock);
cpuclock=clock;
PITCONST=clock/1193182.0;
CGACONST=(clock/(19687503.0/11.0));
MDACONST=(clock/2032125.0);
VGACONST1=(clock/25175000.0);
VGACONST2=(clock/28322000.0);
isa_timing = clock/8000000.0;
bus_timing = clock/(double)cpu_busspeed;
video_updatetiming();
// pclog("PITCONST=%f CGACONST=%f\n", PITCONST, CGACONST);
// pclog("CPUMULTI=%g\n", ((14318184.0*(double)(1 << TIMER_SHIFT)) / (double)models[model].cpu[cpu_manufacturer].cpus[cpu].rspeed));
xt_cpu_multi = (int)((14318184.0*(double)(1 << TIMER_SHIFT)) / (double)models[model].cpu[cpu_manufacturer].cpus[cpu].rspeed);
// pclog("egacycles %i egacycles2 %i temp %f clock %f\n",egacycles,egacycles2,temp,clock);
/* if (video_recalctimings)
video_recalctimings();*/
RTCCONST=clock/32768.0;
TIMER_USEC = (int)((clock / 1000000.0f) * (float)(1 << TIMER_SHIFT));
device_speed_changed();
}
//#define PITCONST (8000000.0/1193000.0)
//#define PITCONST (cpuclock/1193000.0)
void pit_reset()
{
memset(&pit,0,sizeof(PIT));
pit.l[0]=0xFFFF; pit.c[0]=0xFFFF*PITCONST;
pit.l[1]=0xFFFF; pit.c[1]=0xFFFF*PITCONST;
pit.l[2]=0xFFFF; pit.c[2]=0xFFFF*PITCONST;
pit.m[0]=pit.m[1]=pit.m[2]=0;
pit.ctrls[0]=pit.ctrls[1]=pit.ctrls[2]=0;
pit.thit[0]=1;
spkstat=0;
pit.gate[0] = pit.gate[1] = 1;
pit.gate[2] = 0;
pit.using_timer[0] = pit.using_timer[1] = pit.using_timer[2] = 1;
}
void clearpit()
{
pit.c[0]=(pit.l[0]<<2);
}
float pit_timer0_freq()
{
if (pit.l[0])
return 1193182.0f/(float)pit.l[0];
else
return 1193182.0f/(float)0x10000;
}
static void (*pit_set_out_funcs[3])(int new_out, int old_out);
static void pit_set_out(int t, int out)
{
pit_set_out_funcs[t](out, pit.out[t]);
pit.out[t] = out;
}
static void pit_load(int t)
{
int64_t l = pit.l[t] ? pit.l[t] : 0x10000;
timer_process();
pit.newcount[t] = 0;
pit.disabled[t] = 0;
// pclog("pit_load: t=%i l=%x\n", t, l);
switch (pit.m[t])
{
case 0: /*Interrupt on terminal count*/
pit.count[t] = l;
pit.c[t] = (int64_t)((l << TIMER_SHIFT) * PITCONST);
pit_set_out(t, 0);
pit.thit[t] = 0;
pit.enabled[t] = pit.gate[t];
break;
case 1: /*Hardware retriggerable one-shot*/
pit.enabled[t] = 1;
break;
case 2: /*Rate generator*/
if (pit.initial[t])
{
pit.count[t] = l - 1;
pit.c[t] = (int64_t)(((l - 1) << TIMER_SHIFT) * PITCONST);
pit_set_out(t, 1);
pit.thit[t] = 0;
}
pit.enabled[t] = pit.gate[t];
break;
case 3: /*Square wave mode*/
if (pit.initial[t])
{
pit.count[t] = l;
pit.c[t] = (int64_t)((((l + 1) >> 1) << TIMER_SHIFT) * PITCONST);
pit_set_out(t, 1);
pit.thit[t] = 0;
}
pit.enabled[t] = pit.gate[t];
// pclog("pit_load: square wave mode c=%x\n", pit.c[t]);
break;
case 4: /*Software triggered stobe*/
if (!pit.thit[t] && !pit.initial[t])
pit.newcount[t] = 1;
else
{
pit.count[t] = l;
pit.c[t] = (int64_t)((l << TIMER_SHIFT) * PITCONST);
pit_set_out(t, 0);
pit.thit[t] = 0;
}
pit.enabled[t] = pit.gate[t];
break;
case 5: /*Hardware triggered stobe*/
pit.enabled[t] = 1;
break;
}
pit.initial[t] = 0;
pit.running[t] = pit.enabled[t] && pit.using_timer[t] && !pit.disabled[t];
timer_update_outstanding();
// pclog("pit_load: t=%i running=%i thit=%i enabled=%i m=%i l=%x c=%g gate=%i\n", t, pit.running[t], pit.thit[t], pit.enabled[t], pit.m[t], pit.l[t], pit.c[t], pit.gate[t]);
}
void pit_set_gate(int t, int gate)
{
int64_t l = pit.l[t] ? pit.l[t] : 0x10000;
if (pit.disabled[t])
{
pit.gate[t] = gate;
return;
}
timer_process();
switch (pit.m[t])
{
case 0: /*Interrupt on terminal count*/
case 4: /*Software triggered stobe*/
pit.enabled[t] = gate;
break;
case 1: /*Hardware retriggerable one-shot*/
case 5: /*Hardware triggered stobe*/
if (gate && !pit.gate[t])
{
pit.count[t] = l;
pit.c[t] = (int64_t)((l << TIMER_SHIFT) * PITCONST);
pit_set_out(t, 0);
pit.thit[t] = 0;
pit.enabled[t] = 1;
}
break;
case 2: /*Rate generator*/
if (gate && !pit.gate[t])
{
pit.count[t] = l - 1;
pit.c[t] = (int64_t)(((l - 1) << TIMER_SHIFT) * PITCONST);
pit_set_out(t, 1);
pit.thit[t] = 0;
}
pit.enabled[t] = gate;
break;
case 3: /*Square wave mode*/
if (gate && !pit.gate[t])
{
pit.count[t] = l;
pit.c[t] = (int64_t)((((l + 1) >> 1) << TIMER_SHIFT) * PITCONST);
pit_set_out(t, 1);
pit.thit[t] = 0;
}
pit.enabled[t] = gate;
break;
}
pit.gate[t] = gate;
pit.running[t] = pit.enabled[t] && pit.using_timer[t] && !pit.disabled[t];
timer_update_outstanding();
// pclog("pit_set_gate: t=%i gate=%i\n", t, gate);
}
static void pit_over(int t)
{
int64_t l = pit.l[t] ? pit.l[t] : 0x10000;
if (pit.disabled[t])
{
pit.count[t] += 0xffff;
pit.c[t] += (int)((0xffff << TIMER_SHIFT) * PITCONST);
return;
}
// if (!t) pclog("pit_over: t=%i l=%x c=%x %i hit=%i\n", t, pit.l[t], pit.c[t], pit.c[t] >> TIMER_SHIFT, pit.thit[t]);
switch (pit.m[t])
{
case 0: /*Interrupt on terminal count*/
case 1: /*Hardware retriggerable one-shot*/
if (!pit.thit[t])
pit_set_out(t, 1);
pit.thit[t] = 1;
pit.count[t] += 0xffff;
pit.c[t] += (int64_t)((0xffff << TIMER_SHIFT) * PITCONST);
break;
case 2: /*Rate generator*/
pit.count[t] += l;
pit.c[t] += (int)((l << TIMER_SHIFT) * PITCONST);
pit_set_out(t, 0);
pit_set_out(t, 1);
break;
case 3: /*Square wave mode*/
if (pit.out[t])
{
pit_set_out(t, 0);
pit.count[t] += (l >> 1);
pit.c[t] += (int64_t)(((l >> 1) << TIMER_SHIFT) * PITCONST);
}
else
{
pit_set_out(t, 1);
pit.count[t] += ((l + 1) >> 1);
pit.c[t] = (int64_t)((((l + 1) >> 1) << TIMER_SHIFT) * PITCONST);
}
// if (!t) pclog("pit_over: square wave mode c=%x %lli %f\n", pit.c[t], tsc, PITCONST);
break;
case 4: /*Software triggered strove*/
if (!pit.thit[t])
{
pit_set_out(t, 0);
pit_set_out(t, 1);
}
if (pit.newcount[t])
{
pit.newcount[t] = 0;
pit.count[t] += l;
pit.c[t] += (int64_t)((l << TIMER_SHIFT) * PITCONST);
}
else
{
pit.thit[t] = 1;
pit.count[t] += 0xffff;
pit.c[t] += (int64_t)((0xffff << TIMER_SHIFT) * PITCONST);
}
break;
case 5: /*Hardware triggered strove*/
if (!pit.thit[t])
{
pit_set_out(t, 0);
pit_set_out(t, 1);
}
pit.thit[t] = 1;
pit.count[t] += 0xffff;
pit.c[t] += (int64_t)((0xffff << TIMER_SHIFT) * PITCONST);
break;
}
pit.running[t] = pit.enabled[t] && pit.using_timer[t] && !pit.disabled[t];
}
int pit_get_timer_0()
{
int read = (int)((int64_t)((pit.c[0] + ((1 << TIMER_SHIFT) - 1)) / PITCONST) >> TIMER_SHIFT);
//pclog("pit_get_timer_0: t=%i using_timer=%i m=%i\n", 0, pit.using_timer[0], pit.m[0]);
if (pit.m[0] == 2)
read++;
if (read < 0)
read = 0;
if (read > 0x10000)
read = 0x10000;
if (pit.m[0] == 3)
read <<= 1;
return read;
}
static int pit_read_timer(int t)
{
timer_clock();
// pclog("pit_read_timer: t=%i using_timer=%i m=%i\n", t, pit.using_timer[t], pit.m[t]);
if (pit.using_timer[t])
{
int read = (int)((int64_t)((pit.c[t] + ((1 << TIMER_SHIFT) - 1)) / PITCONST) >> TIMER_SHIFT);
if (pit.m[t] == 2)
read++;
if (read < 0)
read = 0;
if (read > 0x10000)
read = 0x10000;
if (pit.m[t] == 3)
read <<= 1;
return read;
}
if (pit.m[t] == 2)
return pit.count[t] + 1;
return pit.count[t];
}
extern int ins;
void pit_write(uint16_t addr, uint8_t val, void *priv)
{
int t;
cycles -= (int)PITCONST;
// /*if (val != 0x40) */pclog("Write PIT %04X %02X %04X:%08X %i %i\n",addr,val,CS,pc,ins, pit.gate[0]);
switch (addr&3)
{
case 3: /*CTRL*/
if ((val&0xC0)==0xC0)
{
if (!(val&0x20))
{
if (val & 2)
pit.rl[0] = pit.using_timer[0] ? (int)(((int64_t) (pit.c[0] / PITCONST)) >> TIMER_SHIFT) : pit.count[0];
if (val & 4)
pit.rl[1] = pit.using_timer[1] ? (int)(((int64_t) (pit.c[1] / PITCONST)) >> TIMER_SHIFT) : pit.count[1];
if (val & 8)
pit.rl[2] = pit.using_timer[2] ? (int)(((int64_t) (pit.c[2] / PITCONST)) >> TIMER_SHIFT) : pit.count[2];
}
if (!(val & 0x10))
{
if (val & 2)
{
pit.read_status[0] = (pit.ctrls[0] & 0x3f) | 0x40 | (pit.out[0] ? 0x80 : 0);
pit.do_read_status[0] = 1;
}
if (val & 4)
{
pit.read_status[1] = (pit.ctrls[1] & 0x3f) | 0x40 | (pit.out[1] ? 0x80 : 0);
pit.do_read_status[1] = 1;
}
if (val & 8)
{
pit.read_status[2] = (pit.ctrls[2] & 0x3f) | 0x40 | (pit.out[2] ? 0x80 : 0);
pit.do_read_status[2] = 1;
}
}
return;
}
t = val >> 6;
pit.ctrl=val;
if ((val>>7)==3)
{
printf("Bad PIT reg select\n");
return;
// dumpregs();
// exit(-1);
}
// printf("CTRL write %02X\n",val);
if (!(pit.ctrl&0x30))
{
pit.rl[t] = pit_read_timer(t);
// pclog("Timer latch %f %04X %04X\n",pit.c[0],pit.rl[0],pit.l[0]);
pit.ctrl |= 0x30;
pit.rereadlatch[t] = 0;
pit.rm[t] = 3;
pit.latched[t] = 1;
}
else
{
pit.ctrls[val>>6] = val;
pit.rm[val>>6]=pit.wm[val>>6]=(pit.ctrl>>4)&3;
pit.m[val>>6]=(val>>1)&7;
if (pit.m[val>>6]>5)
pit.m[val>>6]&=3;
if (!(pit.rm[val>>6]))
{
pit.rm[val>>6]=3;
pit.rl[t] = pit_read_timer(t);
}
pit.rereadlatch[val>>6]=1;
if ((val>>6)==2) ppispeakon=speakon=(pit.m[2]==0)?0:1;
pit.initial[t] = 1;
if (!pit.m[val >> 6])
pit_set_out(val >> 6, 0);
else
pit_set_out(val >> 6, 1);
pit.disabled[val >> 6] = 1;
// pclog("ppispeakon %i\n",ppispeakon);
}
pit.wp=0;
pit.thit[pit.ctrl>>6]=0;
break;
case 0: case 1: case 2: /*Timers*/
t=addr&3;
// if (t==2) ppispeakon=speakon=0;
// pclog("Write timer %02X %i\n",pit.ctrls[t],pit.wm[t]);
switch (pit.wm[t])
{
case 1:
pit.l[t]=val;
// pit.thit[t]=0;
pit_load(t);
// pit.c[t]=((int64_t)pit.l[t])*PITCONST;
// if (!t)
// picintc(1);
break;
case 2:
pit.l[t]=(val<<8);
// pit.thit[t]=0;
pit_load(t);
// pit.c[t]=pit.l[t]*PITCONST;
// if (!t)
// picintc(1);
break;
case 0:
pit.l[t]&=0xFF;
pit.l[t]|=(val<<8);
pit_load(t);
// pit.c[t]=pit.l[t]*PITCONST;
// pclog("%04X %f\n",pit.l[t],pit.c[t]);
// pit.thit[t]=0;
pit.wm[t]=3;
// if (!t)
// picintc(1);
break;
case 3:
pit.l[t]&=0xFF00;
pit.l[t]|=val;
pit.wm[t]=0;
break;
}
speakval=(((float)pit.l[2]/(float)pit.l[0])*0x4000)-0x2000;
// printf("Speakval now %i\n",speakval);
// if (speakval>0x2000)
// printf("Speaker overflow - %i %i %04X %04X\n",pit.l[0],pit.l[2],pit.l[0],pit.l[2]);
if (speakval>0x2000) speakval=0x2000;
/* if (!pit.l[t])
{
pit.l[t]|=0x10000;
pit.c[t]=pit.l[t]*PITCONST;
}*/
break;
}
}
uint8_t pit_read(uint16_t addr, void *priv)
{
int t;
uint8_t temp;
cycles -= (int)PITCONST;
// printf("Read PIT %04X ",addr);
switch (addr&3)
{
case 0: case 1: case 2: /*Timers*/
t = addr & 3;
if (pit.do_read_status[t])
{
pit.do_read_status[t] = 0;
temp = pit.read_status[t];
break;
}
if (pit.rereadlatch[addr & 3] && !pit.latched[addr & 3])
{
pit.rereadlatch[addr & 3] = 0;
pit.rl[t] = pit_read_timer(t);
}
switch (pit.rm[addr & 3])
{
case 0:
temp = pit.rl[addr & 3] >> 8;
pit.rm[addr & 3] = 3;
pit.latched[addr & 3] = 0;
pit.rereadlatch[addr & 3] = 1;
break;
case 1:
temp = (pit.rl[addr & 3]) & 0xFF;
pit.latched[addr & 3] = 0;
pit.rereadlatch[addr & 3] = 1;
break;
case 2:
temp = (pit.rl[addr & 3]) >> 8;
pit.latched[addr & 3] = 0;
pit.rereadlatch[addr & 3] = 1;
break;
case 3:
temp = (pit.rl[addr & 3]) & 0xFF;
if (pit.m[addr & 3] & 0x80)
pit.m[addr & 3] &= 7;
else
pit.rm[addr & 3] = 0;
break;
}
break;
case 3: /*Control*/
temp = pit.ctrl;
break;
}
// pclog("%02X\n", temp);
// printf("%02X %i %i %04X:%04X %i\n",temp,pit.rm[addr&3],pit.wp,cs>>4,pc, ins);
return temp;
}
void pit_poll()
{
// printf("Poll pit %f %f %f\n",pit.c[0],pit.c[1],pit.c[2]);
if (pit.c[0] < 1 && pit.running[0])
pit_over(0);
if (pit.c[1] < 1 && pit.running[1])
pit_over(1);
if (pit.c[2] < 1 && pit.running[2])
pit_over(2);
}
void pit_timer_over(void *p)
{
int timer = (int) p;
// pclog("pit_timer_over %i\n", timer);
pit_over(timer);
}
void pit_clock(int t)
{
if (pit.thit[t] || !pit.enabled[t])
return;
if (pit.using_timer[t])
return;
pit.count[t] -= (pit.m[t] == 3) ? 2 : 1;
if (!pit.count[t])
pit_over(t);
}
void pit_set_using_timer(int t, int using_timer)
{
// pclog("pit_set_using_timer: t=%i using_timer=%i\n", t, using_timer);
timer_process();
if (pit.using_timer[t] && !using_timer)
pit.count[t] = pit_read_timer(t);
if (!pit.using_timer[t] && using_timer)
pit.c[t] = (int64_t)((((int64_t) pit.count[t]) << TIMER_SHIFT) * PITCONST);
pit.using_timer[t] = using_timer;
pit.running[t] = pit.enabled[t] && pit.using_timer[t] && !pit.disabled[t];
timer_update_outstanding();
}
void pit_set_out_func(int t, void (*func)(int new_out, int old_out))
{
pit_set_out_funcs[t] = func;
}
void pit_null_timer(int new_out, int old_out)
{
}
void pit_irq0_timer(int new_out, int old_out)
{
if (new_out && !old_out)
picint(1);
if (!new_out)
picintc(1);
}
void pit_irq0_timer_pcjr(int new_out, int old_out)
{
if (new_out && !old_out)
{
picint(1);
pit_clock(1);
}
if (!new_out)
picintc(1);
}
void pit_refresh_timer_xt(int new_out, int old_out)
{
if (new_out && !old_out)
dma_channel_read(0);
}
void pit_refresh_timer_at(int new_out, int old_out)
{
if (new_out && !old_out)
ppi.pb ^= 0x10;
}
void pit_speaker_timer(int new_out, int old_out)
{
int l;
speaker_update();
l = pit.l[2] ? pit.l[2] : 0x10000;
if (l < 25)
speakon = 0;
else
speakon = new_out;
ppispeakon = new_out;
}
void pit_init()
{
io_sethandler(0x0040, 0x0004, pit_read, NULL, NULL, pit_write, NULL, NULL, NULL);
pit.gate[0] = pit.gate[1] = 1;
pit.gate[2] = 0;
pit.using_timer[0] = pit.using_timer[1] = pit.using_timer[2] = 1;
timer_add(pit_timer_over, &pit.c[0], &pit.running[0], (void *)0);
timer_add(pit_timer_over, &pit.c[1], &pit.running[1], (void *)1);
timer_add(pit_timer_over, &pit.c[2], &pit.running[2], (void *)2);
pit_set_out_func(0, pit_irq0_timer);
pit_set_out_func(1, pit_null_timer);
pit_set_out_func(2, pit_speaker_timer);
}