From f4322fa8bc0a34b2fb3f63c84ab1ad4fb1647c4e Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Thu, 25 Feb 1993 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1993-02-25

---
 gnot/screen.h |  3 ++-
 pc/screen.h   |  3 ++-
 pc/trap.c     |  2 +-
 port/devbit.c | 13 ++++---------
 power/trap.c  |  3 ++-
 ss/screen.h   |  3 ++-
 ss/trap.c     |  1 +
 7 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/gnot/screen.h b/gnot/screen.h
index f7c92d1c1306c0819fc85c7ab4006538f645beea..ca23d47e4206e948453ca0795685c18068114cfe 100644
--- a/gnot/screen.h
+++ b/gnot/screen.h
@@ -9,7 +9,8 @@ struct Mouseinfo{
 	int	dy;
 	int	track;		/* update cursor on screen */
 	Mouse;
-	int	changed;	/* mouse structure changed since last read */
+	ulong	counter;	/* increments every update */
+	ulong	lastcounter;	/* value when /dev/mouse read */
 	Rendez	r;
 	int	newbuttons;	/* interrupt time access only */
 	int	clock;		/* check mouse.track on RTE */
diff --git a/pc/screen.h b/pc/screen.h
index 8a58efe952162df5f165aa48efa4bb6d6fd0de46..82777234e53787dc21d125fc0f795464d7ab98cd 100644
--- a/pc/screen.h
+++ b/pc/screen.h
@@ -9,7 +9,8 @@ struct Mouseinfo{
 	int	dy;
 	int	track;		/* update cursor on screen */
 	Mouse;
-	int	changed;	/* mouse structure changed since last read */
+	ulong	counter;	/* increments every update */
+	ulong	lastcounter;	/* value when /dev/mouse read */
 	Rendez	r;
 	int	newbuttons;	/* interrupt time access only */
 	int	clock;		/* check mouse.track on RTE */
diff --git a/pc/trap.c b/pc/trap.c
index 0ab10cec82f870caf41130f5633c93eb9314fa45..dff6cfb9059a016274397dffe5d45df445f97275 100644
--- a/pc/trap.c
+++ b/pc/trap.c
@@ -242,9 +242,9 @@ trap(Ureg *ur)
 	 */
 	c = v&~0x7;
 	if(c==Int0vec || c==Int1vec){
+		outb(Int0ctl, EOI);
 		if(c == Int1vec)
 			outb(Int1ctl, EOI);
-		outb(Int0ctl, EOI);
 	}
 
 	if(v>=256 || (h = halloc.ivec[v]) == 0){
diff --git a/port/devbit.c b/port/devbit.c
index 600494713ff1295d331f0d5de52154c9a2355c1f..6a4c143836b64613ae29420830c4286cf7dffeeb 100644
--- a/port/devbit.c
+++ b/port/devbit.c
@@ -524,21 +524,16 @@ bitread(Chan *c, void *va, long n, ulong offset)
 		 */
 		if(n < 14)
 			error(Ebadblt);
-	    Again:
-		while(mouse.changed == 0)
+		while(mousechanged(0) == 0)
 			sleep(&mouse.r, mousechanged, 0);
 		lock(&cursor);
-		if(mouse.changed == 0){
-			unlock(&cursor);
-			goto Again;
-		}
 		p = va;
 		p[0] = 'm';
 		p[1] = mouse.buttons;
 		BPLONG(p+2, mouse.xy.x);
 		BPLONG(p+6, mouse.xy.y);
 		BPLONG(p+10, TK2MS(MACHP(0)->ticks));
-		mouse.changed = 0;
+		mouse.lastcounter = mouse.counter;
 		unlock(&cursor);
 		return 14;
 	}
@@ -2081,7 +2076,7 @@ mouseupdate(int dolock)
 	mouse.clock = 0;
 	mouse.track = 0;
 	mouse.buttons = mouse.newbuttons;
-	mouse.changed = 1;
+	mouse.counter++;
 
 	if(dolock){
 		unlock(&cursor);
@@ -2167,7 +2162,7 @@ int
 mousechanged(void *m)
 {
 	USED(m);
-	return mouse.changed;
+	return mouse.lastcounter != mouse.counter;
 }
 
 /*
diff --git a/power/trap.c b/power/trap.c
index ebf6523a17e0c48a1678c7413711d1fc711b9039..933e2d4e895cab52c4a547a07b3da197d2480ac7 100644
--- a/power/trap.c
+++ b/power/trap.c
@@ -423,7 +423,8 @@ notify(Ureg *ur)
 	sp -= 3*BY2WD;
 	*(ulong*)(sp+2*BY2WD) = sp+3*BY2WD;	/* arg 2 is string */
 	u->svr1 = ur->r1;			/* save away r1 */
-	ur->r1 = (ulong)u->ureg;		/* arg 1 is ureg* */
+	ur->r1 = (ulong)u->ureg;		/* arg 1 (R1) is ureg* */
+	*(ulong*)(sp+1*BY2WD) = (ulong)u->ureg;	/* arg 1 0(FP) is ureg* */
 	*(ulong*)(sp+0*BY2WD) = 0;		/* arg 0 is pc */
 	ur->usp = sp;
 	ur->pc = (ulong)u->notify;
diff --git a/ss/screen.h b/ss/screen.h
index f7c92d1c1306c0819fc85c7ab4006538f645beea..ca23d47e4206e948453ca0795685c18068114cfe 100644
--- a/ss/screen.h
+++ b/ss/screen.h
@@ -9,7 +9,8 @@ struct Mouseinfo{
 	int	dy;
 	int	track;		/* update cursor on screen */
 	Mouse;
-	int	changed;	/* mouse structure changed since last read */
+	ulong	counter;	/* increments every update */
+	ulong	lastcounter;	/* value when /dev/mouse read */
 	Rendez	r;
 	int	newbuttons;	/* interrupt time access only */
 	int	clock;		/* check mouse.track on RTE */
diff --git a/ss/trap.c b/ss/trap.c
index 5d581619d05a0613ab201aaf2a1e07cfec9e7374..e26af4f64860b34e682c6e953842415cb10b3ccf 100644
--- a/ss/trap.c
+++ b/ss/trap.c
@@ -454,6 +454,7 @@ notify(Ureg *ur)
 		*(ulong*)(sp+1*BY2WD) = (ulong)u->ureg;	/* arg 1 is ureg* (compat) */
 		u->svr7 = ur->r7;			/* save away r7 */
 		ur->r7 = (ulong)u->ureg;		/* arg 1 is ureg* */
+		*(ulong*)(sp+1*BY2WD) = (ulong)u->ureg;	/* arg 1 0(FP) is ureg* */
 		*(ulong*)(sp+0*BY2WD) = 0;		/* arg 0 is pc */
 		ur->usp = sp;
 		ur->pc = (ulong)u->notify;