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86Box/src/pit.c

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/*IBM AT -
Write B0
Write aa55
Expects aa55 back*/
#include <inttypes.h>
#if 1
#include <math.h>
#endif
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <wchar.h>
#include "86box.h"
#include "cpu/cpu.h"
#include "dma.h"
#include "io.h"
#include "nmi.h"
#include "pic.h"
#include "timer.h"
#include "pit.h"
#include "ppi.h"
#include "device.h"
#include "timer.h"
#include "machine/machine.h"
#include "sound/sound.h"
#include "sound/snd_speaker.h"
#include "video/video.h"
PIT pit, pit2;
double cpuclock, PITCONSTD,
SYSCLK,
isa_timing, bus_timing;
uint64_t PITCONST, ISACONST,
CGACONST,
MDACONST, HERCCONST,
VGACONST1, VGACONST2,
RTCCONST;
int io_delay = 5;
int64_t firsttime = 1;
static void pit_dump_and_disable_timer(PIT *pit, int t);
static void
pit_set_out(PIT *pit, int t, int out)
{
pit->set_out_funcs[t](out, pit->out[t]);
pit->out[t] = out;
}
static void
pit_set_gate_no_timer(PIT *pit, int t, int gate)
{
int64_t l = pit->l[t] ? pit->l[t] : 0x10000LL;
if (pit->disabled[t]) {
pit->gate[t] = gate;
return;
}
switch (pit->m[t]) {
case 0: /*Interrupt on terminal count*/
case 4: /*Software triggered strobe*/
if (pit->using_timer[t] && !pit->running[t])
timer_set_delay_u64(&pit->timer[t], (uint64_t)(l * PITCONST));
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;
if (pit->using_timer[t])
timer_set_delay_u64(&pit->timer[t], (uint64_t)(l * PITCONST));
pit_set_out(pit, 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;
if (pit->using_timer[t])
timer_set_delay_u64(&pit->timer[t], (uint64_t)(l * PITCONST));
pit_set_out(pit, 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;
if (pit->using_timer[t])
timer_set_delay_u64(&pit->timer[t], (uint64_t)(((l + 1) >> 1) * PITCONST));
pit_set_out(pit, 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];
if (pit->using_timer[t] && !pit->running[t])
pit_dump_and_disable_timer(pit, t);
}
static void
pit_over(PIT *pit, int t)
{
int64_t l = pit->l[t] ? pit->l[t] : 0x10000;
if (pit->disabled[t]) {
pit->count[t] += 0xffff;
if (pit->using_timer[t])
timer_advance_u64(&pit->timer[t], (uint64_t)(0xffff * PITCONST));
return;
}
switch (pit->m[t]) {
case 0: /*Interrupt on terminal count*/
case 1: /*Hardware retriggerable one-shot*/
if (!pit->thit[t])
pit_set_out(pit, t, 1);
pit->thit[t] = 1;
pit->count[t] += 0xffff;
if (pit->using_timer[t])
timer_advance_u64(&pit->timer[t], (uint64_t)(0xffff * PITCONST));
break;
case 2: /*Rate generator*/
pit->count[t] += l;
if (pit->using_timer[t])
timer_advance_u64(&pit->timer[t], (uint64_t)(l * PITCONST));
pit_set_out(pit, t, 0);
pit_set_out(pit, t, 1);
break;
case 3: /*Square wave mode*/
if (pit->out[t]) {
pit_set_out(pit, t, 0);
pit->count[t] += (l >> 1);
if (pit->using_timer[t])
timer_advance_u64(&pit->timer[t], (uint64_t)((l >> 1) * PITCONST));
} else {
pit_set_out(pit, t, 1);
pit->count[t] += ((l + 1) >> 1);
if (pit->using_timer[t])
timer_advance_u64(&pit->timer[t], (uint64_t)(((l + 1) >> 1) * PITCONST));
}
break;
case 4: /*Software triggered strobe*/
if (!pit->thit[t]) {
pit_set_out(pit, t, 0);
pit_set_out(pit, t, 1);
}
if (pit->newcount[t]) {
pit->newcount[t] = 0;
pit->count[t] += l;
if (pit->using_timer[t])
timer_advance_u64(&pit->timer[t], (uint64_t)(l * PITCONST));
} else {
pit->thit[t] = 1;
pit->count[t] += 0xffff;
if (pit->using_timer[t])
timer_advance_u64(&pit->timer[t], (uint64_t)(0xffff * PITCONST));
}
break;
case 5: /*Hardware triggered strobe*/
if (!pit->thit[t]) {
pit_set_out(pit, t, 0);
pit_set_out(pit, t, 1);
}
pit->thit[t] = 1;
pit->count[t] += 0xffff;
if (pit->using_timer[t])
timer_advance_u64(&pit->timer[t], (uint64_t)(0xffff * PITCONST));
break;
}
pit->running[t] = pit->enabled[t] && pit->using_timer[t] && !pit->disabled[t];
if (pit->using_timer[t] && !pit->running[t])
pit_dump_and_disable_timer(pit, t);
}
static void
pit_clock(PIT *pit, 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] == 0)
pit_over(pit, t);
}
static void
pit_timer_over(void *p)
{
PIT_nr *pit_nr = (PIT_nr *)p;
PIT *pit = pit_nr->pit;
int t = pit_nr->nr;
pit_over(pit, t);
}
static int
pit_read_timer(PIT *pit, int t)
{
int read;
if (pit->using_timer[t] && !(pit->m[t] == 3 && !pit->gate[t]) && timer_is_enabled(&pit->timer[t])) {
// read = (int)((timer_get_remaining_u64(&pit->timer[t])) / PITCONST);
read = (int) round(((double) timer_get_remaining_u64(&pit->timer[t])) / (PITCONSTD * 4294967296.0));
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];
}
/*Dump timer count back to pit->count[], and disable timer. This should be used
when stopping a PIT timer, to ensure the correct value can be read back.*/
static void
pit_dump_and_disable_timer(PIT *pit, int t)
{
if (pit->using_timer[t] && timer_is_enabled(&pit->timer[t])) {
pit->count[t] = pit_read_timer(pit, t);
timer_disable(&pit->timer[t]);
}
}
static void
pit_load(PIT *pit, int t)
{
int l = pit->l[t] ? pit->l[t] : 0x10000;
pit->newcount[t] = 0;
pit->disabled[t] = 0;
switch (pit->m[t]) {
case 0: /*Interrupt on terminal count*/
pit->count[t] = l;
if (pit->using_timer[t])
timer_set_delay_u64(&pit->timer[t], (uint64_t)(l * PITCONST));
pit_set_out(pit, 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;
if (pit->using_timer[t])
timer_set_delay_u64(&pit->timer[t], (uint64_t)((l - 1) * PITCONST));
pit_set_out(pit, 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;
if (pit->using_timer[t])
timer_set_delay_u64(&pit->timer[t], (uint64_t)(((l + 1) >> 1) * PITCONST));
pit_set_out(pit, t, 1);
pit->thit[t] = 0;
}
pit->enabled[t] = pit->gate[t];
break;
case 4: /*Software triggered strobe*/
if (!pit->thit[t] && !pit->initial[t])
pit->newcount[t] = 1;
else {
pit->count[t] = l;
if (pit->using_timer[t])
timer_set_delay_u64(&pit->timer[t], (uint64_t)(l * PITCONST));
pit_set_out(pit, t, 0);
pit->thit[t] = 0;
}
pit->enabled[t] = pit->gate[t];
break;
case 5: /*Hardware triggered strobe*/
pit->enabled[t] = 1;
break;
}
pit->initial[t] = 0;
pit->running[t] = pit->enabled[t] && pit->using_timer[t] && !pit->disabled[t];
if (pit->using_timer[t] && !pit->running[t])
pit_dump_and_disable_timer(pit, t);
}
static void
pit_write(uint16_t addr, uint8_t val, void *priv)
{
PIT *pit = (PIT *)priv;
double sv = 0.0;
int t;
switch (addr & 3) {
case 3: /* control */
if ((val & 0xC0) == 0xC0) {
if (!(val & 0x20)) {
if (val & 2)
pit->rl[0] = (uint32_t)pit_read_timer(pit, 0);
if (val & 4)
pit->rl[1] = (uint32_t)pit_read_timer(pit, 1);
if (val & 8)
pit->rl[2] = (uint32_t)pit_read_timer(pit, 2);
}
if (!(val & 0x10)) {
if (val & 2) {
pit->read_status[0] = (pit->ctrls[0] & 0x3f) | (pit->out[0] ? 0x80 : 0);
pit->do_read_status[0] = 1;
}
if (val & 4) {
pit->read_status[1] = (pit->ctrls[1] & 0x3f) | (pit->out[1] ? 0x80 : 0);
pit->do_read_status[1] = 1;
}
if (val & 8) {
pit->read_status[2] = (pit->ctrls[2] & 0x3f) | (pit->out[2] ? 0x80 : 0);
pit->do_read_status[2] = 1;
}
}
return;
}
t = val >> 6;
pit->ctrl = val;
if ((val >> 7) == 3)
return;
if (!(pit->ctrl & 0x30)) {
pit->rl[t] = (uint32_t)pit_read_timer(pit, t);
pit->ctrl |= 0x30;
pit->rereadlatch[t] = 0;
pit->rm[t] = 3;
pit->latched[t] = 1;
} else {
pit->ctrls[t] = val;
pit->rm[t] = pit->wm[t] = (pit->ctrl >> 4) & 3;
pit->m[t] = (val >> 1) & 7;
if (pit->m[t] > 5)
pit->m[t] &= 3;
if (!(pit->rm[t])) {
pit->rm[t] = 3;
pit->rl[t] = (uint32_t)pit_read_timer(pit, t);
}
pit->rereadlatch[t] = 1;
pit->initial[t] = 1;
if (!pit->m[t])
pit_set_out(pit, t, 0);
else
pit_set_out(pit, t, 1);
pit->disabled[t] = 1;
}
pit->wp = 0;
pit->thit[t] = 0;
break;
case 0:
case 1:
case 2: /* the actual timers */
t = addr & 3;
switch (pit->wm[t]) {
case 0:
pit->l[t] &= 0xff;
pit->l[t] |= (val << 8);
pit_load(pit, t);
pit->wm[t] = 3;
break;
case 1:
pit->l[t] = val;
pit_load(pit, t);
break;
case 2:
pit->l[t] = (val << 8);
pit_load(pit, t);
break;
case 3:
pit->l[t] &= 0xFF00;
pit->l[t] |= val;
pit->wm[t] = 0;
break;
}
/* PIT latches are in fractions of 60 ms, so convert to sample using the formula below. */
sv = (((double) pit->l[2]) / 60.0) * 16384.0;
speakval = ((int) sv) - 0x2000;
if (speakval > 0x2000)
speakval = 0x2000;
break;
}
}
static uint8_t
pit_read(uint16_t addr, void *priv)
{
PIT *pit = (PIT *)priv;
uint8_t temp = 0xff;
int t;
switch (addr & 3) {
case 3: /* control */
temp = pit->ctrl;
break;
case 0:
case 1:
case 2: /*the actual 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(pit, 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;
}
return temp;
}
/* FIXME: Should be removed. */
static void
pit_null_timer(int new_out, int old_out)
{
}
/* FIXME: Should be moved to machine.c (default for most machine). */
static void
pit_irq0_timer(int new_out, int old_out)
{
if (new_out && !old_out)
picint(1);
if (!new_out)
picintc(1);
}
static 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(void)
{
int i;
pit_reset(&pit);
for (i = 0; i < 3; i++) {
pit.pit_nr[i].nr = i;
pit.pit_nr[i].pit = &pit;
pit.gate[i] = 1;
pit.using_timer[i] = 1;
timer_add(&pit.timer[i], pit_timer_over, (void *)&pit.pit_nr[i], 0);
}
io_sethandler(0x0040, 0x0004, pit_read, NULL, NULL, pit_write, NULL, NULL, &pit);
/* Timer 0: The TOD clock. */
pit_set_out_func(&pit, 0, pit_irq0_timer);
/* Timer 1: Unused. */
pit_set_out_func(&pit, 1, pit_null_timer);
/* Timer 2: speaker and cassette. */
pit_set_out_func(&pit, 2, pit_speaker_timer);
pit.gate[2] = 0;
}
static void
pit_irq0_ps2(int new_out, int old_out)
{
if (new_out && !old_out) {
picint(1);
pit_set_gate_no_timer(&pit2, 0, 1);
}
if (!new_out)
picintc(1);
if (!new_out && old_out)
pit_clock(&pit2, 0);
}
static void
pit_nmi_ps2(int new_out, int old_out)
{
nmi = new_out;
if (nmi)
nmi_auto_clear = 1;
}
void
pit_ps2_init()
{
pit_reset(&pit2);
pit2.gate[0] = 0;
pit2.using_timer[0] = 0;
pit2.disabled[0] = 1;
pit2.pit_nr[0].nr = 0;
pit2.pit_nr[0].pit = &pit2;
timer_add(&pit2.timer[0], pit_timer_over, (void *)&pit2.pit_nr[0], 0);
io_sethandler(0x0044, 0x0001, pit_read, NULL, NULL, pit_write, NULL, NULL, &pit2);
io_sethandler(0x0047, 0x0001, pit_read, NULL, NULL, pit_write, NULL, NULL, &pit2);
pit_set_out_func(&pit, 0, pit_irq0_ps2);
pit_set_out_func(&pit2, 0, pit_nmi_ps2);
}
void
pit_reset(PIT *pit)
{
int i;
memset(pit, 0, sizeof(PIT));
for (i = 0; i < 3; i++) {
pit->ctrls[i] = 0;
pit->thit[i] = 0; /* Should be only thit[0]? */
pit->m[i] = 0;
pit->gate[i] = 1;
pit->l[i] = 0xffff;
pit->using_timer[i] = 1;
}
pit->thit[0] = 1;
/* Disable speaker gate. */
pit->gate[2] = 0;
}
void
pit_set_clock(int clock)
{
/* Set default CPU/crystal clock and xt_cpu_multi. */
if (machines[machine].cpu[cpu_manufacturer].cpus[cpu_effective].cpu_type >= CPU_286) {
if (clock == 66666666)
cpuclock = 200000000.0 / 3.0;
else if (clock == 33333333)
cpuclock = 100000000.0 / 3.0;
else
cpuclock = (double) clock;
PITCONSTD = (cpuclock / 1193182.0);
PITCONST = (uint64_t) (PITCONSTD * (double)(1ull << 32));
CGACONST = (uint64_t) ((cpuclock / (19687503.0/11.0)) * (double)(1ull << 32));
ISACONST = (uint64_t) ((cpuclock / 8000000.0) * (double)(1ull << 32));
xt_cpu_multi = 1ULL;
} else {
cpuclock = 14318184.0;
PITCONSTD = 12.0;
PITCONST = (12ULL << 32ULL);
CGACONST = (8ULL << 32ULL);
xt_cpu_multi = 3ULL;
switch (machines[machine].cpu[cpu_manufacturer].cpus[cpu_effective].rspeed) {
case 7159092:
if (machines[machine].cpu[cpu_manufacturer].cpus[cpu_effective].cpu_flags & CPU_ALTERNATE_XTAL) {
cpuclock = 28636368.0;
xt_cpu_multi = 4ULL;
} else
xt_cpu_multi = 2ULL;
break;
case 8000000:
cpuclock = 24000000.0;
break;
case 9545456:
cpuclock = 28636368.0;
break;
case 10000000:
cpuclock = 30000000.0;
break;
case 12000000:
cpuclock = 36000000.0;
break;
case 16000000:
cpuclock = 48000000.0;
break;
default:
if (machines[machine].cpu[cpu_manufacturer].cpus[cpu_effective].cpu_flags & CPU_ALTERNATE_XTAL) {
cpuclock = 28636368.0;
xt_cpu_multi = 6ULL;
}
break;
}
if (cpuclock == 28636368.0) {
PITCONSTD = 24.0;
PITCONST = (24ULL << 32LL);
CGACONST = (16ULL << 32LL);
} else if (cpuclock != 14318184.0) {
PITCONSTD = (cpuclock / 1193182.0);
PITCONST = (uint64_t) (PITCONSTD * (double)(1ull << 32));
CGACONST = (uint64_t) (((cpuclock/(19687503.0/11.0)) * (double)(1ull << 32)));
}
ISACONST = (1ULL << 32ULL);
}
xt_cpu_multi <<= 32ULL;
/* Delay for empty I/O ports. */
io_delay = (int) round(((double) machines[machine].cpu[cpu_manufacturer].cpus[cpu_effective].rspeed) / 1000000.0);
MDACONST = (uint64_t) (cpuclock / 2032125.0 * (double)(1ull << 32));
HERCCONST = MDACONST;
VGACONST1 = (uint64_t) (cpuclock / 25175000.0 * (double)(1ull << 32));
VGACONST2 = (uint64_t) (cpuclock / 28322000.0 * (double)(1ull << 32));
RTCCONST = (uint64_t) (cpuclock / 32768.0 * (double)(1ull << 32));
TIMER_USEC = (uint64_t)((cpuclock / 1000000.0) * (double)(1ull << 32));
isa_timing = (cpuclock / (double)8000000.0);
bus_timing = (cpuclock / (double)cpu_busspeed);
if (cpu_busspeed >= 30000000)
SYSCLK = bus_timing * 4.0;
else
SYSCLK = bus_timing * 3.0;
video_update_timing();
device_speed_changed();
}
void
clearpit(void)
{
// pit.c[0] = (pit.l[0] << 2);
}
void
pit_set_gate(PIT *pit, int t, int gate)
{
if (pit->disabled[t]) {
pit->gate[t] = gate;
return;
}
pit_set_gate_no_timer(pit, t, gate);
}
void
pit_set_using_timer(PIT *pit, int t, int using_timer)
{
timer_process();
if (pit->using_timer[t] && !using_timer)
pit->count[t] = pit_read_timer(pit, t);
pit->running[t] = pit->enabled[t] && using_timer && !pit->disabled[t];
if (!pit->using_timer[t] && using_timer && pit->running[t])
timer_set_delay_u64(&pit->timer[t], (uint64_t)(pit->count[t] * PITCONST));
else if (!pit->running[t])
timer_disable(&pit->timer[t]);
pit->using_timer[t] = using_timer;
}
void
pit_set_out_func(PIT *pit, int t, void (*func)(int new_out, int old_out))
{
pit->set_out_funcs[t] = func;
}
void
pit_irq0_timer_pcjr(int new_out, int old_out)
{
if (new_out && !old_out) {
picint(1);
pit_clock(&pit, 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;
}
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