Apple-2-Tools
/
apple2ix
mirror of https://github.com/mauiaaron/apple2.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
apple2ix/src/timing.c

564 lines
16 KiB
C
Raw Blame History

/*
* Apple // emulator for *ix
*
* This software package is subject to the GNU General Public License
* version 3 or later (your choice) as published by the Free Software
* Foundation.
*
* Copyright 2013-2015 Aaron Culliney
*
*/
/*
* 65c02 CPU timing support. Source inspired/derived from AppleWin.
*
* Simplified timing loop for each execution period:
*
* ..{...+....[....|..................|.........]....^....|....^....^....}......
* ti MBB CHK CHK MBE CHX SPK MBX tj ZZZ
*
* - ti : timing sample begin (lock out interface thread)
* - tj : timing sample end (unlock interface thread)
* - [ : cpu65_run()
* - ] : cpu65_run() finished
* - CHK : incoming timing_checkpoint_cycles() call from IO (bumps cycles_count_total)
* - CHX : update remainder of timing_checkpoint_cycles() for execution period
* - MBB : Mockingboard begin
* - MBE : Mockingboard end/flush (output)
* - MBX : Mockingboard end video frame (output)
* - SPK : Speaker output
* - ZZZ : housekeeping+sleep (or not)
*
*/
#include "common.h"
#define DEBUG_TIMING (!defined(NDEBUG) && 0) // enable to print timing stats
#if DEBUG_TIMING
# define TIMING_LOG(...) LOG(__VA_ARGS__)
#else
# define TIMING_LOG(...)
#endif
#define DISK_MOTOR_QUIET_NSECS 2000000
// VBL constants?
#define uCyclesPerLine 65 // 25 cycles of HBL & 40 cycles of HBL'
#define uVisibleLinesPerFrame (64*3) // 192
#define uLinesPerFrame (262) // 64 in each third of the screen & 70 in VBL
#define dwClksPerFrame (uCyclesPerLine * uLinesPerFrame) // 17030
// cycle counting
double cycles_persec_target = CLK_6502;
unsigned long long cycles_count_total = 0;
int cycles_speaker_feedback = 0;
int32_t cpu65_cycles_to_execute = 0; // cycles-to-execute by cpu65_run()
int32_t cpu65_cycle_count = 0; // cycles currently excuted by cpu65_run()
static int32_t cycles_checkpoint_count = 0;
static unsigned int g_dwCyclesThisFrame = 0;
// scaling and speed adjustments
#if !MOBILE_DEVICE
static bool auto_adjust_speed = true;
#endif
static bool is_paused = false;
static unsigned long _pause_spinLock = 0;
double cpu_scale_factor = 1.0;
double cpu_altscale_factor = 1.0;
bool is_fullspeed = false;
bool alt_speed_enabled = false;
// misc
volatile uint8_t emul_reinitialize = 1;
#ifdef AUDIO_ENABLED
static bool emul_reinitialize_audio = true;
static bool emul_pause_audio = false;
static bool emul_resume_audio = false;
#endif
static bool cpu_shutting_down = false;
pthread_t cpu_thread_id = 0;
pthread_mutex_t interface_mutex = { 0 };
pthread_cond_t dbg_thread_cond = PTHREAD_COND_INITIALIZER;
pthread_cond_t cpu_thread_cond = PTHREAD_COND_INITIALIZER;
// -----------------------------------------------------------------------------
__attribute__((constructor(CTOR_PRIORITY_LATE)))
static void _init_timing(void) {
pthread_mutexattr_t attr;
pthread_mutexattr_init(&attr);
pthread_mutex_init(&interface_mutex, &attr);
}
struct timespec timespec_diff(struct timespec start, struct timespec end, bool *negative) {
struct timespec t;
if (negative)
{
*negative = false;
}
// if start > end, swizzle...
if ( (start.tv_sec > end.tv_sec) || ((start.tv_sec == end.tv_sec) && (start.tv_nsec > end.tv_nsec)) )
{
t=start;
start=end;
end=t;
if (negative)
{
*negative = true;
}
}
// assuming time_t is signed ...
if (end.tv_nsec < start.tv_nsec)
{
t.tv_sec = end.tv_sec - start.tv_sec - 1;
t.tv_nsec = 1000000000 + end.tv_nsec - start.tv_nsec;
}
else
{
t.tv_sec = end.tv_sec - start.tv_sec;
t.tv_nsec = end.tv_nsec - start.tv_nsec;
}
return t;
}
static inline struct timespec timespec_add(struct timespec start, unsigned long nsecs) {
start.tv_nsec += nsecs;
if (start.tv_nsec > NANOSECONDS_PER_SECOND)
{
start.tv_sec += (start.tv_nsec / NANOSECONDS_PER_SECOND);
start.tv_nsec %= NANOSECONDS_PER_SECOND;
}
return start;
}
static void _timing_initialize(double scale) {
is_fullspeed = (scale >= CPU_SCALE_FASTEST);
if (!is_fullspeed) {
cycles_persec_target = CLK_6502 * scale;
}
#ifdef AUDIO_ENABLED
speaker_reset();
//TIMING_LOG("ClockRate:%0.2lf ClockCyclesPerSpeakerSample:%0.2lf", cycles_persec_target, speaker_cyclesPerSample());
#endif
}
#if !TESTING
static
#endif
void reinitialize(void) {
#if !TESTING
assert(pthread_self() == cpu_thread_id);
#endif
cycles_count_total = 0;
vm_initialize();
softswitches = SS_TEXT | SS_IOUDIS | SS_C3ROM | SS_LCWRT | SS_LCSEC;
video_setpage( 0 );
video_redraw();
cpu65_init();
timing_initialize();
#ifdef AUDIO_ENABLED
MB_Reset();
#endif
}
void timing_initialize(void) {
#if !TESTING
assert(cpu_isPaused() || (pthread_self() == cpu_thread_id));
#endif
_timing_initialize(alt_speed_enabled ? cpu_altscale_factor : cpu_scale_factor);
}
void timing_toggleCPUSpeed(void) {
assert(cpu_isPaused() || (pthread_self() == cpu_thread_id));
alt_speed_enabled = !alt_speed_enabled;
timing_initialize();
}
#ifdef AUDIO_ENABLED
void timing_reinitializeAudio(void) {
SPINLOCK_ACQUIRE(&_pause_spinLock);
assert(pthread_self() != cpu_thread_id);
assert(cpu_isPaused());
emul_reinitialize_audio = true;
emul_pause_audio = false;
emul_resume_audio = false;
SPINLOCK_RELINQUISH(&_pause_spinLock);
}
#endif
void cpu_pause(void) {
assert(pthread_self() != cpu_thread_id);
SPINLOCK_ACQUIRE(&_pause_spinLock);
do {
if (is_paused) {
break;
}
// CPU thread will be paused when it next tries to acquire interface_mutex
LOG("PAUSING CPU...");
#ifdef AUDIO_ENABLED
if (!emul_reinitialize_audio) {
emul_pause_audio = true;
}
#endif
pthread_mutex_lock(&interface_mutex);
is_paused = true;
} while (0);
SPINLOCK_RELINQUISH(&_pause_spinLock);
}
void cpu_resume(void) {
assert(pthread_self() != cpu_thread_id);
SPINLOCK_ACQUIRE(&_pause_spinLock);
do {
if (!is_paused) {
break;
}
// CPU thread will be unblocked to acquire interface_mutex
#ifdef AUDIO_ENABLED
if (!emul_reinitialize_audio) {
emul_resume_audio = true;
}
#endif
LOG("RESUMING CPU...");
pthread_mutex_unlock(&interface_mutex);
is_paused = false;
} while (0);
SPINLOCK_RELINQUISH(&_pause_spinLock);
}
bool cpu_isPaused(void) {
return is_paused;
}
#if !MOBILE_DEVICE
bool timing_shouldAutoAdjustSpeed(void) {
double speed = alt_speed_enabled ? cpu_altscale_factor : cpu_scale_factor;
return auto_adjust_speed && (speed < CPU_SCALE_FASTEST);
}
#endif
static void *cpu_thread(void *dummyptr) {
assert(pthread_self() == cpu_thread_id);
LOG("cpu_thread : initialized...");
struct timespec deltat;
#if !MOBILE_DEVICE
struct timespec disk_motor_time;
#endif
struct timespec t0; // the target timer
struct timespec ti, tj; // actual time samples
bool negative = false;
long drift_adj_nsecs = 0; // generic drift adjustment between target and actual
int debugging_cycles0 = 0;
int debugging_cycles = 0;
#if DEBUG_TIMING
unsigned long dbg_ticks = 0;
int speaker_neg_feedback = 0;
int speaker_pos_feedback = 0;
unsigned int dbg_cycles_executed = 0;
#endif
do
{
#ifdef AUDIO_ENABLED
LOG("CPUTHREAD %lu LOCKING FOR MAYBE INITIALIZING AUDIO ...", cpu_thread_id);
pthread_mutex_lock(&interface_mutex);
if (emul_reinitialize_audio) {
emul_reinitialize_audio = false;
speaker_destroy();
MB_Destroy();
audio_shutdown();
audio_init();
speaker_init();
MB_Initialize();
}
pthread_mutex_unlock(&interface_mutex);
LOG("UNLOCKING FOR MAYBE INITIALIZING AUDIO ...");
#endif
if (emul_reinitialize) {
reinitialize();
}
LOG("cpu_thread : begin main loop ...");
clock_gettime(CLOCK_MONOTONIC, &t0);
do {
SCOPE_TRACE_CPU("CPU mainloop");
// -LOCK----------------------------------------------------------------------------------------- SAMPLE ti
#ifdef AUDIO_ENABLED
if (UNLIKELY(emul_pause_audio)) {
emul_pause_audio = false;
audio_pause();
}
#endif
pthread_mutex_lock(&interface_mutex);
#ifdef AUDIO_ENABLED
if (UNLIKELY(emul_resume_audio)) {
emul_resume_audio = false;
audio_resume();
}
#endif
clock_gettime(CLOCK_MONOTONIC, &ti);
deltat = timespec_diff(t0, ti, &negative);
if (deltat.tv_sec)
{
if (!is_fullspeed) {
TIMING_LOG("NOTE : serious divergence from target time ...");
}
t0 = ti;
deltat = timespec_diff(t0, ti, &negative);
}
t0 = timespec_add(t0, EXECUTION_PERIOD_NSECS); // expected interval
drift_adj_nsecs = negative ? ~deltat.tv_nsec : deltat.tv_nsec;
// set up increment & decrement counters
cpu65_cycles_to_execute = (cycles_persec_target / 1000); // cycles_persec_target * EXECUTION_PERIOD_NSECS / NANOSECONDS_PER_SECOND
if (!is_fullspeed) {
cpu65_cycles_to_execute += cycles_speaker_feedback;
}
if (cpu65_cycles_to_execute < 0)
{
cpu65_cycles_to_execute = 0;
}
#ifdef AUDIO_ENABLED
MB_StartOfCpuExecute();
#endif
if (is_debugging) {
debugging_cycles0 = cpu65_cycles_to_execute;
debugging_cycles = cpu65_cycles_to_execute;
}
do {
if (is_debugging) {
cpu65_cycles_to_execute = 1;
}
cpu65_cycle_count = 0;
cycles_checkpoint_count = 0;
cpu65_run(); // run emulation for cpu65_cycles_to_execute cycles ...
if (is_debugging) {
debugging_cycles -= cpu65_cycle_count;
if (c_debugger_should_break() || (debugging_cycles <= 0)) {
int err = 0;
if ((err = pthread_cond_signal(&dbg_thread_cond))) {
ERRLOG("pthread_cond_signal : %d", err);
}
if ((err = pthread_cond_wait(&cpu_thread_cond, &interface_mutex))) {
ERRLOG("pthread_cond_wait : %d", err);
}
if (debugging_cycles <= 0) {
cpu65_cycle_count = debugging_cycles0 - debugging_cycles/*<=0*/;
break;
}
}
}
if (emul_reinitialize) {
reinitialize();
}
} while (is_debugging);
#if DEBUG_TIMING
dbg_cycles_executed += cpu65_cycle_count;
#endif
g_dwCyclesThisFrame += cpu65_cycle_count;
#ifdef AUDIO_ENABLED
MB_UpdateCycles(); // update 6522s (NOTE: do this before updating cycles_count_total)
#endif
timing_checkpoint_cycles();
#if CPU_TRACING
cpu65_trace_checkpoint();
#endif
#ifdef AUDIO_ENABLED
speaker_flush(); // play audio
#endif
if (g_dwCyclesThisFrame >= dwClksPerFrame) {
g_dwCyclesThisFrame -= dwClksPerFrame;
#ifdef AUDIO_ENABLED
MB_EndOfVideoFrame();
#endif
}
clock_gettime(CLOCK_MONOTONIC, &tj);
pthread_mutex_unlock(&interface_mutex);
// -UNLOCK--------------------------------------------------------------------------------------- SAMPLE tj
#if !MOBILE_DEVICE
if (timing_shouldAutoAdjustSpeed()) {
disk_motor_time = timespec_diff(disk6.motor_time, tj, &negative);
assert(!negative);
if (!is_fullspeed &&
#ifdef AUDIO_ENABLED
!speaker_isActive() &&
#endif
!video_isDirty() && (!disk6.motor_off && (disk_motor_time.tv_sec || disk_motor_time.tv_nsec > DISK_MOTOR_QUIET_NSECS)) )
{
TIMING_LOG("auto switching to full speed");
_timing_initialize(CPU_SCALE_FASTEST);
}
}
#endif
if (!is_fullspeed) {
deltat = timespec_diff(ti, tj, &negative);
assert(!negative);
long sleepfor = 0;
if (!deltat.tv_sec)
{
sleepfor = EXECUTION_PERIOD_NSECS - drift_adj_nsecs - deltat.tv_nsec;
}
if (sleepfor <= 0)
{
// lagging ...
static time_t throttle_warning = 0;
if (t0.tv_sec - throttle_warning > 0)
{
TIMING_LOG("not sleeping to catch up ... %ld . %ld", deltat.tv_sec, deltat.tv_nsec);
throttle_warning = t0.tv_sec;
}
}
else
{
deltat.tv_sec = 0;
deltat.tv_nsec = sleepfor;
TRACE_CPU_BEGIN("sleep");
nanosleep(&deltat, NULL);
TRACE_CPU_END();
}
#if DEBUG_TIMING
// collect timing statistics
if (speaker_neg_feedback > cycles_speaker_feedback)
{
speaker_neg_feedback = cycles_speaker_feedback;
}
if (speaker_pos_feedback < cycles_speaker_feedback)
{
speaker_pos_feedback = cycles_speaker_feedback;
}
dbg_ticks += EXECUTION_PERIOD_NSECS;
if ((dbg_ticks % NANOSECONDS_PER_SECOND) == 0)
{
TIMING_LOG("tick:(%ld.%ld) real:(%ld.%ld) cycles exe: %d ... speaker feedback: %d/%d", t0.tv_sec, t0.tv_nsec, ti.tv_sec, ti.tv_nsec, dbg_cycles_executed, speaker_neg_feedback, speaker_pos_feedback);
dbg_cycles_executed = 0;
dbg_ticks = 0;
speaker_neg_feedback = 0;
speaker_pos_feedback = 0;
}
#endif
}
#if !MOBILE_DEVICE
if (timing_shouldAutoAdjustSpeed()) {
if (is_fullspeed && (
#ifdef AUDIO_ENABLED
speaker_isActive() ||
#endif
video_isDirty() || (disk6.motor_off && (disk_motor_time.tv_sec || disk_motor_time.tv_nsec > DISK_MOTOR_QUIET_NSECS))) )
{
double speed = alt_speed_enabled ? cpu_altscale_factor : cpu_scale_factor;
if (speed < CPU_SCALE_FASTEST) {
TIMING_LOG("auto switching to configured speed");
_timing_initialize(speed);
}
}
}
#endif
if (UNLIKELY(emul_reinitialize)) {
break;
}
#ifdef AUDIO_ENABLED
if (UNLIKELY(emul_reinitialize_audio)) {
break;
}
#endif
if (UNLIKELY(cpu_shutting_down)) {
break;
}
} while (1);
if (UNLIKELY(cpu_shutting_down)) {
break;
}
} while (1);
#ifdef AUDIO_ENABLED
speaker_destroy();
MB_Destroy();
audio_shutdown();
#endif
return NULL;
}
void timing_startCPU(void) {
cpu_shutting_down = false;
int err = TEMP_FAILURE_RETRY(pthread_create(&cpu_thread_id, NULL, (void *)&cpu_thread, (void *)NULL));
if (err) {
RELEASE_ERRLOG("pthread_create failed!");
RELEASE_BREAK();
}
}
void timing_stopCPU(void) {
cpu_shutting_down = true;
LOG("Emulator waiting for CPU thread clean up...");
if (pthread_join(cpu_thread_id, NULL)) {
ERRLOG("OOPS: pthread_join of CPU thread ...");
}
}
unsigned int CpuGetCyclesThisVideoFrame(void) {
timing_checkpoint_cycles();
return g_dwCyclesThisFrame + cycles_checkpoint_count;
}
// Called when an IO-reg is accessed & accurate global cycle count info is needed
void timing_checkpoint_cycles(void) {
assert(pthread_self() == cpu_thread_id);
const int32_t d = cpu65_cycle_count - cycles_checkpoint_count;
assert(d >= 0);
cycles_count_total += d;
cycles_checkpoint_count = cpu65_cycle_count;
}
Reference in New Issue View Git Blame Copy Permalink