4 files changed, 199 insertions(+), 49 deletions(-)

M pc/mouse.c
M pc/screen.h
M port/devmouse.c
M port/tod.c

@@ 101,6 101,80 @@ ps2mouse(void)
 	mousetype = MousePS2;
 }
 
+static int intellimouse;
+static int resolution;
+static int accelerated;
+
+static void
+setaccelerated(int x)
+{
+	accelerated = x;
+	switch(mousetype){
+	case MousePS2:
+		i8042auxcmd(0xE7);
+		break;
+	default:
+		mouseaccelerate(x);
+		break;
+	}
+}
+
+static void
+setlinear(void)
+{
+	accelerated = 0;
+	switch(mousetype){
+	case MousePS2:
+		i8042auxcmd(0xE6);
+		break;
+	default:
+		mouseaccelerate(0);
+		break;
+	}
+}
+
+static void
+setres(int n)
+{
+	resolution = n;
+	switch(mousetype){
+	case MousePS2:
+		i8042auxcmd(0xE8);
+		i8042auxcmd(n);
+		break;
+	}
+}
+
+static void
+setintellimouse(void)
+{
+	intellimouse = 1;
+	switch(mousetype){
+	case MousePS2:
+		i8042auxcmd(0xF3);	/* set sample */
+		i8042auxcmd(0xC8);
+		i8042auxcmd(0xF3);	/* set sample */
+		i8042auxcmd(0x64);
+		i8042auxcmd(0xF3);	/* set sample */
+		i8042auxcmd(0x50);
+		break;
+	}
+}
+
+static void
+resetmouse(void)
+{
+	switch(mousetype){
+	case MousePS2:
+		i8042auxcmd(0xF6);
+		i8042auxcmd(0xEA);	/* streaming */
+		i8042auxcmd(0xE8);	/* set resolution */
+		i8042auxcmd(3);
+		i8042auxcmd(0xF4);	/* enabled */
+		break;
+	}
+}
+
 void
 mousectl(char* field[], int n)
 {


@@ 119,44 193,27 @@ mousectl(char* field[], int n)
 		}
 	} else if(strcmp(field[0], "ps2") == 0){
 		ps2mouse();
+	} else if(strcmp(field[0], "ps2intellimouse") == 0){
+		ps2mouse();
+		setintellimouse();
 	} else if(strcmp(field[0], "accelerated") == 0){
-		switch(mousetype){
-		case MousePS2:
-			i8042auxcmd(0xE7);
-			break;
-		default:
-			if(n == 1)
-				mouseaccelerate("1");
-			else
-				mouseaccelerate(field[1]);
-			break;
-		}
+		setaccelerated(n == 1 ? 1 : atoi(field[1]));
 	} else if(strcmp(field[0], "linear") == 0){
-		switch(mousetype){
-		case MousePS2:
-			i8042auxcmd(0xE6);
-			break;
-		default:
-			mouseaccelerate("0");
-			break;
-		}
+		setlinear();
 	} else if(strcmp(field[0], "res") == 0){
-		if(n < 2)
-			n = 1;
-		else
+		if(n >= 2)
 			n = atoi(field[1]);
-		switch(mousetype){
-		case MousePS2:
-			i8042auxcmd(0xE8);
-			i8042auxcmd(n);
-			break;
-		}
+		setres(n);
 	} else if(strcmp(field[0], "reset") == 0){
-		i8042auxcmd(0xF6);
-		i8042auxcmd(0xEA);	/* streaming */
-		i8042auxcmd(0xE8);	/* set resolution */
-		i8042auxcmd(3);
-		i8042auxcmd(0xF4);	/* enabled */
+		resetmouse();
+		if(accelerated)
+			setaccelerated(accelerated);
+		if(resolution)
+			setres(resolution);
+		if(intellimouse)
+			setintellimouse();
+	} else if(strcmp(field[0], "intellimouse") == 0){
+		setintellimouse();
 	}
 	else
 		error(Ebadctl);

@@ 9,7 9,7 @@ struct Cursorinfo {
 extern void mousetrack(int, int, int);
 extern Point mousexy(void);
 
-extern void mouseaccelerate(char*);
+extern void mouseaccelerate(int);
 extern int m3mouseputc(void*, int);
 extern int mouseputc(void*, int);
 

@@ 535,11 535,9 @@ mousexy(void)
 }
 
 void
-mouseaccelerate(char *x)
+mouseaccelerate(int x)
 {
-	if(x == 0)
-		x = "1";
-	mouse.acceleration = atoi(x);
+	mouse.acceleration = x;
 	if(mouse.acceleration < 3)
 		mouse.maxacc = 2;
 	else

@@ 5,22 5,99 @@
 #include	"fns.h"
 #include	"../port/error.h"
 
+// compute nanosecond epoch time from the fastest ticking clock
+// on the system.  converting the time to nanoseconds requires
+// the following formula
+//
+//	t = (((1000000000<<s1)/f)*(ticks>>s2))>>(s1-s2)
+//
+//  where
+//
+//	'f'		is the clock frequency
+//	'ticks'		are clock ticks
+//	's1' and 's2'	are shift ammounts to avoid 64 bit
+//			overflows in the calculations
+//
+//  to avoid too much calculation in gettod(), we calculate
+//
+//	mult = (1000000000<<s1)/f
+//
+//  each time f is set.  f is normally set by a user level
+//  program writing to /dev/fastclock.
+//
+//  To calculate s1 and s2, we have to avoid overflowing our
+//  signed 64 bit calculations.  Also we wish to accomodate
+//  15 minutes of ticks.  This gives us the following
+//  constraints:
+//
+//	1) log2(1000000000<<s1) <= 63
+//	   or s1 <= 33
+//	2) accomodate 15 minutes of ticks without overflow
+//	   or log2(((1000000000<<s1)/f)*((15*60*f)>>s2)) <= 63
+//	   or log2(mult) + 12 + log2(f) - s2 <= 63
+//	   or log2(mult) + log2(f) - 51 <= s2
+//
+//  by definition
+//
+//	3) log2(mult) = log2(1000000000) + s1 - log2(f)
+//	   or log2(mult) = 30 + s1 - log2(f)
+//
+//  To balance the accuracy of the multiplier and the sampled
+//  ticks we set
+//
+//	4) log2(mult) = log2(f>>s2)
+//	   or log2(mult) = log2(f) - s2
+//
+//  Combining 2) and 4) we get
+//
+//	5) log2(f) - s2 + log2(f) - 51 <= s2
+//	   or 2*log2(f) - 51 <= 2*s2
+//	   or log2(f) - 25 <= s2
+//
+//  Combining 3) and 4)
+//
+//	6) 30 + s1 - log2(f) = log2(f) - s2
+//	   or s1 = 2*log2(f) - s2 - 30
+//
+//  Since shifting ticks left doesn't increase accuracy, and
+//  shifting 1000000000 right loses accuracy
+//
+//	7) s2 >= 0
+//	8) s1 >= 0
+//
+//  As an example, that gives us the following
+//
+//	for f = 100, log2(f) = 7
+//
+//		s2 = 0
+//		s1 = 0
+//
+//	for f = 267000000, log2(f) = 28
+//
+//		s2 = 3
+//		s1 = 23
+//
+//	for f = 2000000000, log2(f) = 31
+//
+//		s2 = 6
+//		s1 = 26
+//
+//	for f = 8000000000, log2(f) = 33
+//
+//		s2 = 8
+//		s1 = 28
 
 // frequency of the tod clock
 #define TODFREQ	1000000000LL
 
-enum
-{
-	Log2mult=	22,	// multiplier should have 22 bits
-	Log2todfreq=	30,	// number of significant bits of TODFREQ
-};
-
 static vlong logtab[40];
 
 struct {
 	Lock;
-	int	shift;		// time = (ticks*multiplier)>>shift
+	int	s1;		// time = ((ticks>>s2)*multiplier)>>(s1-s2)
 	vlong	multiplier;	// ...
+	int	s2;		// ...
+	vlong	maxdiff;	// max diff between ticks and last to avoid overflow
 	vlong	hz;		// frequency of fast clock
 	vlong	last;		// last reading of fast clock
 	vlong	off;		// offset from epoch to last


@@ 65,12 142,24 @@ todinit(void)
 void
 todsetfreq(vlong f)
 {
+	int lf;
+
 	// this ensures that the multiplier has 22 bits
 	ilock(&tod);
 	tod.hz = f;
-	tod.shift = Log2mult - Log2todfreq + log2(f);
-	tod.multiplier = (TODFREQ<<tod.shift)/f;
+	lf = log2(f);
+	tod.s2 = lf - 25;
+	if(tod.s2 < 0)
+		tod.s2 = 0;
+	tod.s1 = 2*lf - tod.s2 - 30;
+	if(tod.s1 < 0)
+		tod.s1 = 0;
+	if(tod.s1 > 33)
+		tod.s1 = 33;
+	tod.multiplier = (TODFREQ<<tod.s1)/f;
+	tod.maxdiff = 1LL<<(10 + lf);
 	iunlock(&tod);
+//print("hz %lld mult %lld s1 %d s2 %d maxdiff %lld\n", tod.hz, tod.multiplier, tod.s1, tod.s2, tod.maxdiff);
 }
 
 //


@@ 109,11 198,11 @@ todget(void)
 	diff = ticks - tod.last;
 
 	// convert to epoch
-	x = (diff*tod.multiplier)>>tod.shift;
+	x = ((diff>>tod.s2)*tod.multiplier)>>(tod.s1-tod.s2);
 	x += tod.off;
 
 	// protect against overflows
-	if(diff > (1LL<<(63-Log2mult))){
+	if(diff > tod.maxdiff){
 		tod.last = ticks;
 		tod.off = x;
 	}


@@ 135,10 224,16 @@ todfix(void)
 {
 	if((MACHP(0)->ticks % HZ) != 0)
 		return;
+
+	// once a second apply correction
 	ilock(&tod);
 	if(tod.n > tod.i++)
 		tod.off += tod.delta;
 	iunlock(&tod);
+
+	// once a minute, make sure we don't overflow
+	if((MACHP(0)->ticks % (60*HZ)) == 0)
+		todget();
 }
 
 long