From f05569f01b5dbfe49c7006ccd017091f023eddc3 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Sat, 10 Aug 1991 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1991-08-10

---
 pc/devfloppy.c |  6 ++--
 pc/devhard.c   | 13 +++-----
 pc/devuart.c   | 87 +++++++++++++++++++++++++++-----------------------
 pc/io.h        |  4 +--
 pc/main.c      |  1 +
 pc/trap.c      |  3 --
 port/portdat.h |  4 +++
 port/proc.c    |  7 +++-
 port/queue.c   | 86 ++++++++++++++++++++++++++++---------------------
 9 files changed, 117 insertions(+), 94 deletions(-)

diff --git a/pc/devfloppy.c b/pc/devfloppy.c
index 87b8ecec0e1161c7a512ca7668fc5abdc9376671..aace35e043443eb7293aa03d767c04ff355fb4c4 100644
--- a/pc/devfloppy.c
+++ b/pc/devfloppy.c
@@ -180,6 +180,7 @@ floppyreset(void)
 {
 	Drive *dp;
 	Type *t;
+	int n;
 
 	/*
 	 *  init dependent parameters
@@ -211,8 +212,9 @@ floppyreset(void)
 	 */
 	for(dp = floppy.d; dp < &floppy.d[conf.nfloppy]; dp++){
 		do {
-			dp->ccache = ialloc(dp->t->cap, 1);
-		} while(k64(dp->ccache) != k64(dp->ccache+dp->t->cap));
+			n = 512 * 18 * 2;	/* MF2HD cylinder size */
+			dp->ccache = ialloc(n, 1);
+		} while(k64(dp->ccache) != k64(dp->ccache+n));
 		dp->ccyl = -1;
 	}
 	setvec(Floppyvec, floppyintr);
diff --git a/pc/devhard.c b/pc/devhard.c
index 9b4437239384bb2f623851dd8cf7f6c818e7b980..7fa303ff41fd7a447ba1f74bf2cb38eb826629c6 100644
--- a/pc/devhard.c
+++ b/pc/devhard.c
@@ -13,7 +13,7 @@ typedef	struct Controller	Controller;
 enum
 {
 	/* ports */
-	Pbase=		0x10,
+	Pbase=		0x1F0,
 	Pdata=		Pbase+0,	/* data port (16 bits) */
 	Perror=		Pbase+1,	/* error port */
 	Pcount=		Pbase+2,	/* sector count port */
@@ -164,9 +164,11 @@ hardattach(char *spec)
 			dp->bytes = 512;
 			dp->cap = dp->bytes * dp->cyl * dp->heads * dp->sectors;
 			dp->online = 1;
+			poperror();
 		}
 	}
-	return devattach('f', spec);
+	qunlock(&hard);
+	return devattach('h', spec);
 }
 
 Chan*
@@ -301,17 +303,11 @@ interrupted(void *a)
 static long
 hardident(Drive *dp)
 {
-print("identify hard drive\n");
 	hard.intr = 0;
 	outb(Pdh, dp->dev<<4);
 	outb(Pcmd, Cident);
-print("waiting for hard drive interupt\n");
 	sleep(&hard.r, interrupted, 0);
-print("getting hard drive ident\n");
 	inss(Pdata, &hard.id, 512/2);
-print(" magic %lux lcyls %d rcyl %d lheads %d b2t %d b2s %d ls2t %d\n",
-  hard.id.magic, hard.id.lcyls, hard.id.rcyl, hard.id.lheads,
-  hard.id.b2t, hard.id.b2s, hard.id.ls2t);
 }
 
 static long
@@ -374,7 +370,6 @@ hardintr(Ureg *ur)
 	if(hard.status & Sbusy)
 		panic("disk busy");
 	hard.intr = 1;
-print("hardintr\n");
 	wakeup(&hard.r);
 }
 
diff --git a/pc/devuart.c b/pc/devuart.c
index b33a9b5ad5ae6162622886db63e46ce115b4ac62..0d31c6fcfea7d103c7e68fd4bf2ec6cb471df21e 100644
--- a/pc/devuart.c
+++ b/pc/devuart.c
@@ -32,7 +32,7 @@ enum
 	 Dtr=	(1<<0),		/*  data terminal ready */
 	 Rts=	(1<<1),		/*  request to send */
 	 Ri=	(1<<2),		/*  ring */
-	 Dcd=	(1<<3),		/*  carrier */
+	 Inton=	(1<<3),		/*  turn on interrupts */
 	 Loop=	(1<<4),		/*  loop bask */
 	Lstat=	5,		/* line status */
 	 Inready=(1<<0),	/*  receive buffer full */
@@ -164,10 +164,13 @@ uartsetup(void)
 		 *  set rate to 9600 baud.
 		 *  8 bits/character.
 		 *  1 stop bit.
+		 *  interrupts enabled.
 		 */
 		uartsetbaud(up, 9600);
 		up->sticky[Format] = Bits8;
 		uartwrreg(up, Format, 0);
+		up->sticky[Mctl] |= Inton;
+		uartwrreg(up, Mctl, 0x0);
 	}
 }
 
@@ -209,48 +212,58 @@ uartintr(Uart *up)
 	IOQ *cq;
 	int s, l;
 
-	l = uartrdreg(up, Lstat);
-	s = uartrdreg(up, Istat);
-
-	cq = up->iq;
-	while(l & Inready){
-		ch = uartrdreg(up, Data) & 0xff;
-		if(cq->putc)
-			(*cq->putc)(cq, ch);
-		else {
-			putc(cq, ch);
-			if(up->delim[ch/8] & (1<<(ch&7)) )
+	for(;;){
+		s = uartrdreg(up, Istat);
+		switch(s){
+		case 6:	/* receiver line status */
+			l = uartrdreg(up, Lstat);
+			break;
+	
+		case 4:	/* received data available */
+			cq = up->iq;
+			ch = uartrdreg(up, Data) & 0xff;
+			if(cq->putc)
+				(*cq->putc)(cq, ch);
+			else {
+				putc(cq, ch);
+				if(up->delim[ch/8] & (1<<(ch&7)) )
+					wakeup(&cq->r);
+			}
+			break;
+	
+		case 2:	/* transmitter empty */
+			cq = up->oq;
+			lock(cq);
+			ch = getc(cq);
+			if(ch < 0){
+				up->printing = 0;
 				wakeup(&cq->r);
+			}else
+				outb(up->port + Data, ch);
+			unlock(cq);
+			break;
+	
+		case 0:	/* modem status */
+			l = uartrdreg(up, Mstat);
+			break;
+	
+		default:
+			if(s&1)
+				return;
+			print("weird modem interrupt\n");
+			break;
 		}
-		l = uartrdreg(up, Lstat);
-	}
-
-	/*
-	 *  send next output character
-	 */
-	if(up->printing && (l&Outready)){
-		cq = up->oq;
-		lock(cq);
-		ch = getc(cq);
-		if(ch < 0){
-			up->printing = 0;
-			wakeup(&cq->r);
-		}else
-			outb(up->port + Data, ch);
-		unlock(cq);
 	}
 }
 void
 uartintr0(Ureg *ur)
 {
-	if(uart[0].enabled)
-		uartintr(&uart[0]);
+	uartintr(&uart[0]);
 }
 void
 uartintr1(Ureg *ur)
 {
-	if(uart[1].enabled)
-		uartintr(&uart[1]);
+	uartintr(&uart[1]);
 }
 
 /*
@@ -271,8 +284,8 @@ uartenable(Uart *up)
 
 	/*
 	 *  speed up the clock to poll the uart
-	 */
 	fclockinit();
+	 */
 
 	/*
 	 *  set up i/o routines
@@ -285,21 +298,18 @@ uartenable(Uart *up)
 		up->iq->ptr = up;
 	}
 	up->enabled = 1;
-	up->sticky[Iena] = 0xf;
 
 	/*
  	 *  turn on interrupts
 	 */
+	up->sticky[Iena] = 0x7;
 	uartwrreg(up, Iena, 0);
-	uartwrreg(up, Tctl, 0x0);
 
 	/*
 	 *  turn on DTR and RTS
 	 */
 	uartdtr(up, 1);
 	uartrts(up, 1);
-
-print("uart enabled: Iena=%lux\n", uartrdreg(up, Iena));
 }
 
 /*
@@ -393,9 +403,6 @@ uartstopen(Queue *q, Stream *s)
 	Uart *up;
 	char name[NAMELEN];
 
-print("uartstopen: q=0x%ux, inuse=%d, type=%d, dev=%d, id=%d\n",
-		q, s->inuse, s->type, s->dev, s->id);
-
 	up = &uart[s->id];
 	up->iq->putc = 0;
 	uartenable(up);
diff --git a/pc/io.h b/pc/io.h
index 0a213a62d01902ec96910f0a4d1a60102cf2948d..b3467bcfce4fcc8f5f1594da5a49bffb97542938 100644
--- a/pc/io.h
+++ b/pc/io.h
@@ -7,8 +7,8 @@ enum
 	Int0vec=	16,		/* first 8259 */
 	 Clockvec=	Int0vec+0,	/*  clock interrupts */
 	 Kbdvec=	Int0vec+1,	/*  keyboard interrupts */
-	 Uart0vec=	Int0vec+3,	/*  serial line */
-	 Uart1vec=	Int0vec+4,	/*  modem line */
+	 Uart0vec=	Int0vec+4,	/*  serial line */
+	 Uart1vec=	Int0vec+3,	/*  modem line */
 	 Floppyvec=	Int0vec+6,	/*  floppy interrupts */
 	Int1vec=	Int0vec+8,	/* second 8259 */
 	 Mousevec=	Int1vec+4,	/*  mouse interrupt */
diff --git a/pc/main.c b/pc/main.c
index 6eb0b24661d96f2073f0484baa95d7857d105cb0..24410fda4d9a800355fa3eeb660138f63367ddf1 100644
--- a/pc/main.c
+++ b/pc/main.c
@@ -374,6 +374,7 @@ pmuwrbit(int index, int bit, int pos)
 		return -1;
 	}
 	unlock(&pmulock);
+	return 0;
 }
 
 /*
diff --git a/pc/trap.c b/pc/trap.c
index 15d6411942fd397d428b7fdf5073fb270d882014..c8893d99c30812211c2b163806bad78a371348ea 100644
--- a/pc/trap.c
+++ b/pc/trap.c
@@ -178,9 +178,6 @@ trap(Ureg *ur)
 		return;
 	}
 
-	if(v==19 || v==20)
-		print("trap = %d\n", v);
-
 	/*
 	 *  tell the 8259 that we're done with the
 	 *  highest level interrupt (interrupts are still
diff --git a/port/portdat.h b/port/portdat.h
index 792d7a9a36bace60a774c1d217fd43be1804514c..9bf067d4354f763224294a8b0e1a571e425a02e1 100644
--- a/port/portdat.h
+++ b/port/portdat.h
@@ -220,6 +220,10 @@ struct IOQ
 		void	(*puts)(IOQ*, void*, int);	/* output */
 		int	(*putc)(IOQ*, int);		/* input */
 	};
+	union{
+		int	(*gets)(IOQ*, void*, int);	/* input */
+		int	(*getc)(IOQ*);			/* output */
+	};
 	void	*ptr;
 };
 struct KIOQ
diff --git a/port/proc.c b/port/proc.c
index e105975f23eb877d718360cf10a8351a607875a3..d38a687c2cedbf36d5638ddab2be712a567b6ba7 100644
--- a/port/proc.c
+++ b/port/proc.c
@@ -401,8 +401,11 @@ postnote(Proc *p, int dolock, char *n, int flag)
 	if(dolock)
 		lock(&p->debug);
 
-	if(p->upage == 0)
+	if(p->upage == 0){
+		if(dolock)
+			unlock(&p->debug);
 		errors("noted process disappeared");
+	}
 
 	if(u == 0 || p != u->p){
 		k = kmap(p->upage);
@@ -416,6 +419,8 @@ postnote(Proc *p, int dolock, char *n, int flag)
 	else if(up->nnote == NNOTE-1){
 		if(up != u)
 			kunmap(k);
+		if(dolock)
+			unlock(&p->debug);
 		return 0;
 	}
 	p->notepending = 1;
diff --git a/port/queue.c b/port/queue.c
index 6c7c15b22154fd6345fe3441c2101f54c5dd76c0..a5fab13e3071bb4d67b4762a237c30caf8e85af0 100644
--- a/port/queue.c
+++ b/port/queue.c
@@ -13,21 +13,22 @@ initq(IOQ *q)
 	q->in = q->out = q->buf;
 	q->puts = puts;
 	q->putc = putc;
+	q->gets = gets;
+	q->getc = getc;
 }
 
 int
 putc(IOQ *q, int c)
 {
-	uchar *next;
-
-	if(q->in ==  &q->buf[NQ-1])
-		next = q->buf;
+	uchar *nextin;
+	if(q->in >= &q->buf[sizeof(q->buf)-1])
+		nextin = q->buf;
 	else
-		next = q->in+1;
-	if(next == q->out)
+		nextin = q->in+1;
+	if(nextin == q->out)
 		return -1;
 	*q->in = c;
-	q->in = next;
+	q->in = nextin;
 	return 0;
 }
 
@@ -39,7 +40,7 @@ getc(IOQ *q)
 	if(q->in == q->out)
 		return -1;
 	c = *q->out;
-	if(q->out == &q->buf[NQ-1])
+	if(q->out == q->buf+sizeof(q->buf)-1)
 		q->out = q->buf;
 	else
 		q->out++;
@@ -49,44 +50,61 @@ getc(IOQ *q)
 void
 puts(IOQ *q, void *buf, int n)
 {
-	uchar *next;
-	uchar *p = buf;
+	int m; uchar *nextin;
+	uchar *s = buf;
 
-	for(; n; n--){
-		if(q->in == &q->buf[NQ-1])
-			next = q->buf;
-		else
-			next = q->in + 1;
-		if(next == q->out)
+	while(n){
+		m = q->out - q->in - 1;
+		if(m < 0)
+			m = &q->buf[NQ] - q->in;
+		if(m == 0)
 			break;
-		*q->in = *p++;
-		q->in = next;
+		if(m > n)
+			m = n;
+		memmove(q->in, s, m);
+		n -= m;
+		s += m;
+		nextin = q->in + m;
+		if(nextin >= &q->buf[NQ])
+			q->in = q->buf;
+		else
+			q->in = nextin;
 	}
 }
 
 int
 gets(IOQ *q, void *buf, int n)
 {
-	uchar *p = buf;
+	int m, k = 0; uchar *nextout;
+	uchar *s = buf;
 
-	for(; n && q->out != q->in; n--){
-		*p++ = *q->out;
-		if(q->out == &q->buf[NQ-1])
+	while(n){
+		m = q->in - q->out;
+		if(m < 0)
+			m = &q->buf[NQ] - q->out;
+		if(m == 0)
+			return k;
+		if(m > n)
+			m = n;
+		if(buf)
+			memmove(s, q->out, m);
+		s += m;
+		k += m;
+		n -= m;
+		nextout = q->out + m;
+		if(nextout >= &q->buf[NQ])
 			q->out = q->buf;
 		else
-			q->out++;
+			q->out = nextout;
 	}
-	return p - (uchar*)buf;
+	return k;
 }
 
 int
 cangetc(void *arg)
 {
-	IOQ *q;
-	int n;
-
-	q = (IOQ *)arg;
-	n = q->in - q->out;
+	IOQ *q = (IOQ *)arg;
+	int n = q->in - q->out;
 	if (n < 0)
 		n += sizeof(q->buf);
 	return n;
@@ -95,12 +113,6 @@ cangetc(void *arg)
 int
 canputc(void *arg)
 {
-	IOQ *q;
-	int n;
-
-	q = (IOQ *)arg;
-	n = q->out - q->in - 1;
-	if (n < 0)
-		n += sizeof(q->buf);
-	return n;
+	IOQ *q = (IOQ *)arg;
+	return sizeof(q->buf)-cangetc(q)-1;
 }