Flesh out the timer stuff; hook up controller input to it.

3 files changed, 99 insertions, 27 deletions

diff --git a/emu.c b/emu.c
index 81c3d70..d3d8b4d 100644
--- a/emu.c
+++ b/emu.c
@@ -5,8 +5,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <unistd.h>
-#include <sys/time.h>
+#include <unistd.h>	// for usleep
 
 #include "types.h"
 #include "disas.h"
@@ -686,13 +685,7 @@ static u32 last_retrace_time = 0;
 
 static void do_idle(void)
 {
-	u32 now;
-	struct timeval tv;
-
-//	printf("### IDLE ###\n");
-
-	gettimeofday(&tv, 0);
-	now = 1000000*tv.tv_sec + tv.tv_usec;
+	u32 now = timer_now();
 	if (now < last_retrace_time + PERIOD) {
 //		printf("  sleeping %dus\n", last_retrace_time + PERIOD - now);
 		usleep(last_retrace_time + PERIOD - now);
@@ -701,11 +694,7 @@ static void do_idle(void)
 
 u16 get_video_line(void)
 {
-	u32 now;
-	struct timeval tv;
-
-	gettimeofday(&tv, 0);
-	now = 1000000*tv.tv_sec + tv.tv_usec;
+	u32 now = timer_now();
 	return (now - last_retrace_time) * 625 * FREQ / 2 / 1000000;	// 525 for NTSC
 }
 
@@ -736,8 +725,9 @@ static void run_main(void)
 	}
 
 	if (timer_triggered != timer_handled) {
+		timer_run();
 		timer_handled++;
-		timer_set();
+		timer_set(1000000/250);
 	} else
 		do_idle();
 }
@@ -815,15 +805,18 @@ static void do_controller(void)
 	} while (key);
 }
 
+struct timer timer_controller = {
+	.name = "controller",
+	.time = 20000,
+	.interval = 20000,
+	.run = do_controller
+};
+
 static void run(void)
 {
 	run_main();
 
-	struct timeval tv;
-	u32 now;
-
-	gettimeofday(&tv, 0);
-	now = 1000000*tv.tv_sec + tv.tv_usec;
+	u32 now = timer_now();
 
 	if (now - last_retrace_time >= PERIOD) {
 		static int count = 0;
@@ -842,8 +835,6 @@ static void run(void)
 
 		last_retrace_time = now;
 
-		do_controller();
-
 		mem[0x3d22] |= 2;	// TMB2		FIXME: freq
 
 		if (do_extint1) {
@@ -884,6 +875,8 @@ void emu(void)
 	memset(reg, 0, sizeof reg);
 	reg[7] = mem[0xfff7];	// reset vector
 
+	timer_add(&timer_controller);
+
 	for (;;)
 		run();
 }
diff --git a/timer.c b/timer.c
index b7f1021..0e2c599 100644
--- a/timer.c
+++ b/timer.c
@@ -5,6 +5,7 @@
 #include <sys/time.h>
 #include <signal.h>
 #include <unistd.h>
+#include <stdio.h>
 
 #include "types.h"
 #include "platform.h"
@@ -14,12 +15,23 @@
 
 volatile u32 timer_triggered;
 
-void timer_set(void)
+static struct timer *timers;
+static u32 timer_time;
+
+u32 timer_now(void)
+{
+	struct timeval tv;
+
+	gettimeofday(&tv, 0);
+	return 1000000*tv.tv_sec + tv.tv_usec;
+}
+
+void timer_set(u32 usecs)
 {
 	struct itimerval it;
 
-	it.it_value.tv_sec = 0;
-	it.it_value.tv_usec = 1000000/250;
+	it.it_value.tv_sec = usecs / 1000000;
+	it.it_value.tv_usec = usecs % 1000000;
 	it.it_interval.tv_sec = 0;
 	it.it_interval.tv_usec = 0;
 
@@ -28,6 +40,57 @@ void timer_set(void)
 		fatal("setitimer failed");
 }
 
+void timer_debug(void)
+{
+	printf("timer head = %u, now = %u\n", timer_time, timer_now());
+	struct timer *timer;
+	for (timer = timers; timer; timer = timer->next)
+		printf("timer \"%s\" %dus\n", timer->name, timer->time);
+}
+
+void timer_add(struct timer *timer)
+{
+	u32 time = timer_now() - timer_time + timer->time;
+	struct timer **p = &timers;
+
+	while (*p && (*p)->time <= time) {
+		time -= (*p)->time;
+		p = &(*p)->next;
+	}
+
+	timer->next = *p;
+	*p = timer;
+	timer->time = time;
+	if (timer->next)
+		timer->next->time -= time;
+}
+
+void timer_run(void)
+{
+	u32 now = timer_now();
+	u32 elapsed = now - timer_time;
+
+	struct timer *timer;
+	while ((timer = timers) && timer->time <= elapsed) {
+		timers = timer->next;
+		timer_time += timer->time;
+		elapsed -= timer->time;
+
+printf("running timer \"%s\" (%u)\n", timer->name, now);
+		if (timer->run)
+			timer->run();
+
+		if (timer->interval) {
+			timer->time = timer->interval;
+			timer_add(timer);
+		}
+	}
+
+	if (timer)
+		timer->time -= elapsed;
+	timer_time = now;
+}
+
 static void alarm_handler(int signo, siginfo_t *si, void *uc)
 {
 	timer_triggered++;
@@ -42,5 +105,7 @@ void timer_init(void)
 	sa.sa_flags = SA_SIGINFO;
 	sigaction(SIGALRM, &sa, 0);
 
-	timer_set();
+	timer_time = timer_now();
+
+	timer_set(1);
 }
diff --git a/timer.h b/timer.h
index 4d43789..a426b9e 100644
--- a/timer.h
+++ b/timer.h
@@ -9,7 +9,21 @@
 
 extern volatile u32 timer_triggered;
 
+struct timer {
+	const char *name;
+	u32 time;
+	u32 interval;
+	void (*run)(void);
+	struct timer *next;
+};
+
+void timer_debug(void);
 void timer_init(void);
-void timer_set(void);
+void timer_add(struct timer *timer);
+void timer_run(void);
+u32 timer_now(void);
+
+// XXX: temp
+void timer_set(u32 usecs);
 
 #endif