From 43b828beaacd10f8c9a561a982d1c84270c1f313 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Tue, 6 Aug 1991 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1991-08-06

---
 pc/clock.c        |  1 +
 pc/devfloppy.c    |  1 +
 pc/devuart.c      | 92 +++++++++++++++++++++++++++--------------------
 pc/io.h           |  4 +--
 pc/l.s            | 10 ++++++
 pc/main.c         | 15 +++++++-
 pc/trap.c         | 26 +++++++++++++-
 port/page.c       | 12 ++++++-
 port/pgrp.c       |  1 +
 port/portdat.h    |  9 +++++
 port/proc.c       | 19 ++++++++++
 port/sysproc.c    | 43 ++++++++++++++++++++++
 port/systab.h     |  2 ++
 power/boot.c      |  1 -
 power/devhotrod.c |  5 +--
 15 files changed, 194 insertions(+), 47 deletions(-)

diff --git a/pc/clock.c b/pc/clock.c
index 82af8e911e2769c05e364951c5e118cafdfc7dcb..4ef21ed523977aac0431d1fc2b140e8933dbc93c 100644
--- a/pc/clock.c
+++ b/pc/clock.c
@@ -62,6 +62,7 @@ clock(Ureg *ur)
 
 	checkalarms();
 	mouseclock();
+	uartintr0(ur);
 
 	p = m->proc;
 	if(p){
diff --git a/pc/devfloppy.c b/pc/devfloppy.c
index 61522d42824554f2e94c1dfecf692fdbd52f32ef..50f21a39ff7dedfdc65407f3cef848a201d26f66 100644
--- a/pc/devfloppy.c
+++ b/pc/devfloppy.c
@@ -754,6 +754,7 @@ print("new offset %d instead of %d\n", offset, off+dp->len);
 static void
 floppyintr(Ureg *ur)
 {
+print("floppy intr\n");
 	floppy.intr = 1;
 	wakeup(&floppy.r);
 }
diff --git a/pc/devuart.c b/pc/devuart.c
index 1c688f70a51d03fee202b525282c302615810f82..f049df86ef2d3e66ced2711c1ae05a98459a74bc 100644
--- a/pc/devuart.c
+++ b/pc/devuart.c
@@ -206,44 +206,39 @@ uartintr(Uart *up)
 {
 	int ch;
 	IOQ *cq;
-	int s;
+	int s, l;
 
+	l = uartrdreg(up, Lstat);
 	s = uartrdreg(up, Istat);
-print("uartintr %lux\n", s);
-	switch(s){
-	case 3:
-		/*
-		 *  get any input characters
-		 */
-		cq = up->iq;
-		while(uartrdreg(up, Lstat) & 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)) )
-					wakeup(&cq->r);
-			}
-		}
-		break;
-	case 5:
-		/*
-		 *  send next output character
-		 */
-		if(uartrdreg(up, Lstat)&Outready){
-			cq = up->oq;
-			lock(cq);
-			ch = getc(cq);
-print("<cont %2.2ux>", ch);/**/
-			if(ch < 0){
-				up->printing = 0;
+
+	cq = up->iq;
+	while(l & Inready){
+		ch = uartrdreg(up, Data) & 0xff;
+print("<get %2.2ux>", ch);
+		if(cq->putc)
+			(*cq->putc)(cq, ch);
+		else {
+			putc(cq, ch);
+			if(up->delim[ch/8] & (1<<(ch&7)) )
 				wakeup(&cq->r);
-			}else
-				outb(up->port + Data, ch);
-			unlock(cq);
 		}
-		break;
+		l = uartrdreg(up, Lstat);
+	}
+
+	/*
+	 *  send next output character
+	 */
+	if(up->printing && (l&Outready)){
+		cq = up->oq;
+		lock(cq);
+		ch = getc(cq);
+print("<put %2.2ux>", ch);/**/
+		if(ch < 0){
+			up->printing = 0;
+			wakeup(&cq->r);
+		}else
+			outb(up->port + Data, ch);
+		unlock(cq);
 	}
 }
 void
@@ -263,6 +258,8 @@ uartintr1(Ureg *ur)
 void
 uartenable(Uart *up)
 {
+	int x;
+
 	/*
 	 *  set up i/o routines
 	 */
@@ -287,6 +284,15 @@ uartenable(Uart *up)
 	 */
 	uartdtr(up, 1);
 	uartrts(up, 1);
+
+	/*
+	 *  read interrupt status till there aren't any pending
+	 */
+	while(uartrdreg(up, Istat) != 1){
+		x = splhi();
+		uartintr(up);
+		splx(x);
+	}
 }
 
 /*
@@ -303,6 +309,10 @@ uartspecial(int port, IOQ *oq, IOQ *iq, int baud)
 	up->iq = iq;
 	uartenable(up);
 	uartsetbaud(up, baud);
+	if(port == 0){
+		if(serial(0) < 0)
+			print("can't turn on serial port power\n");
+	}
 
 	if(iq){
 		/*
@@ -366,9 +376,14 @@ uartstopen(Queue *q, Stream *s)
 	Uart *up;
 	char name[NAMELEN];
 
-	kprint("uartstopen: q=0x%ux, inuse=%d, type=%d, dev=%d, id=%d\n",
+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];
+	uartenable(up);
+	if(s->id==0 && serial(0)<0)
+		print("can't turn on serial power\n");
+
 	qlock(up);
 	up->wq = WR(q);
 	WR(q)->ptr = up;
@@ -399,6 +414,9 @@ uartstclose(Queue *q)
 	WR(q)->ptr = 0;
 	RD(q)->ptr = 0;
 	qunlock(up);
+
+	if(serial(1) < 0)
+		print("can't turn off serial power\n");
 }
 
 static void
@@ -511,9 +529,6 @@ uartreset(void)
 {
 	Uart *up;
 
-	if(serial(0) < 0)
-		print("can't turn on power\n");
-
 	uartsetup();
 	for(up = uart; up < &uart[2]; up++){
 		if(up->nostream)
@@ -522,7 +537,6 @@ uartreset(void)
 		initq(up->iq);
 		up->oq = ialloc(sizeof(IOQ), 0);
 		initq(up->oq);
-		uartenable(up);
 	}
 }
 
diff --git a/pc/io.h b/pc/io.h
index f20e2737bad17075e96c87ce48fe0101da0a5a1d..0a213a62d01902ec96910f0a4d1a60102cf2948d 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,	/*  inerrupt from uart b */
-	 Uart1vec=	Int0vec+4,	/*  inerrupt from uart a */
+	 Uart0vec=	Int0vec+3,	/*  serial line */
+	 Uart1vec=	Int0vec+4,	/*  modem line */
 	 Floppyvec=	Int0vec+6,	/*  floppy interrupts */
 	Int1vec=	Int0vec+8,	/* second 8259 */
 	 Mousevec=	Int1vec+4,	/*  mouse interrupt */
diff --git a/pc/l.s b/pc/l.s
index f4fa78a8ac1e9eb10244793cc99edf1918c90283..e3b5f14d770dab1a3cf83d0ee3adee6a6c1b88c4 100644
--- a/pc/l.s
+++ b/pc/l.s
@@ -488,3 +488,13 @@ TEXT	fpsave(SB),$0
 TEXT	fprestore(SB),$0
 	RET
 
+
+/*
+ *  set configuration register
+ */
+TEXT	config(SB),$0
+	MOVL	l+0(FP),AX
+	MOVL	$0x3F3,DX
+	OUTB
+	OUTB
+	RET
diff --git a/pc/main.c b/pc/main.c
index 4527eb17477b31682ab7b4dfea852d9a9ddf2641..3dd33264683af430c5b48c1b96daa21c23f2b0af 100644
--- a/pc/main.c
+++ b/pc/main.c
@@ -285,7 +285,12 @@ enum
 	Pmudata=	0x198,
 
 	Pmucsr=		0x199,
-	 Busy=	0x1,
+	 Busy=		0x1,
+
+	/*
+	 *  configuration port
+	 */
+	Pconfig=	0x3F3,
 };
 
 /*
@@ -368,6 +373,14 @@ pmuwrbit(int index, int bit, int pos)
 int
 serial(int onoff)
 {
+	int x;
+
+	/*
+	 *  set config (enable everything)
+	 */
+	x = splhi();
+	config(0x00);
+	splx(x);
 	return pmuwrbit(1, onoff, 6);
 }
 
diff --git a/pc/trap.c b/pc/trap.c
index 20e2dd561936e094eb930d0ba04cf1d5f8b4e8bc..5c49bd793183cad11a46282ba0a0ca86bfddf063 100644
--- a/pc/trap.c
+++ b/pc/trap.c
@@ -176,6 +176,9 @@ trap(Ureg *ur)
 	if(v>=256 || ivec[v] == 0)
 		panic("bad trap type %d %lux\n", v, ur->pc);
 
+	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
@@ -183,9 +186,9 @@ trap(Ureg *ur)
 	 */
 	c = v&~0x7;
 	if(c==Int0vec || c==Int1vec){
-		outb(Int0ctl, EOI);
 		if(c == Int1vec)
 			outb(Int1ctl, EOI);
+		outb(Int0ctl, EOI);
 	}
 
 	/*
@@ -194,6 +197,27 @@ trap(Ureg *ur)
 	(*ivec[v])(ur);
 }
 
+/*
+ *  print 8259 status
+ */
+void
+dump8259(void)
+{
+	int c;
+
+	outb(Int0ctl, 0x0a);	/* read ir */
+	print("ir0 %lux\n", inb(Int0ctl));
+	outb(Int0ctl, 0x0b);	/* read is */
+	print("is0 %lux\n", inb(Int0ctl));
+	print("im0 %lux\n", inb(Int0aux));
+
+	outb(Int1ctl, 0x0a);	/* read ir */
+	print("ir1 %lux\n", inb(Int1ctl));
+	outb(Int1ctl, 0x0b);	/* read is */
+	print("is1 %lux\n", inb(Int1ctl));
+	print("im1 %lux\n", inb(Int1aux));
+}
+
 /*
  *  dump registers
  */
diff --git a/port/page.c b/port/page.c
index 14a5f26757f63cedaef0741a0dd76cbd04804172..a3998b546d03d4582660431fcf6894c37554c802 100644
--- a/port/page.c
+++ b/port/page.c
@@ -168,16 +168,26 @@ newpage(int clear, Segment **s, ulong va)
 	/* The kp test is a poor guard against the pager deadlocking */
 	while((palloc.freecount < HIGHWATER && u->p->kp == 0) || palloc.freecount == 0) {
 		palloc.wanted++;
-		unlock(&palloc);			
+		unlock(&palloc);
 		if(s && *s) {
 			qunlock(&((*s)->lk));
 			*s = 0;
 		}
 		qlock(&palloc.pwait);			/* Hold memory requesters here */
 
+		if(waserror()) {
+			qunlock(&palloc.pwait);
+			lock(&palloc);
+			palloc.wanted--;
+			unlock(&palloc);
+			nexterror();
+		}
+
 		kickpager();
 		tsleep(&palloc.r, ispages, 0, 1000);
 
+		poperror();
+
 		qunlock(&palloc.pwait);
 		lock(&palloc);
 		palloc.wanted--;
diff --git a/port/pgrp.c b/port/pgrp.c
index 9cd03c0b081f30301f85bfa368171039ffb4529d..fde7389c6c25ed0ed2c7811c2ee09632eb928105 100644
--- a/port/pgrp.c
+++ b/port/pgrp.c
@@ -120,6 +120,7 @@ newpgrp(void)
 			p->ref = 1;
 			p->pgrpid = ++pgrpalloc.pgrpid;
 			p->nmtab = 0;
+			memset(p->rendhash, 0, sizeof(p->rendhash));
 			unlock(&pgrpalloc);
 			return p;
 		}
diff --git a/port/portdat.h b/port/portdat.h
index a7b567153775fce9ae67ad681d2a2f88502b86f7..35e5faa7d8fddd3a913875345056eefad09a031b 100644
--- a/port/portdat.h
+++ b/port/portdat.h
@@ -355,6 +355,9 @@ struct Segment
 	Pte	*map[SEGMAPSIZE];	/* segment pte map */
 };
 
+#define RENDHASH	32
+#define REND(p,s)	((p)->rendhash[(s)%RENDHASH])
+
 struct Pgrp
 {
 	Ref;				/* also used as a lock when mounting */
@@ -365,6 +368,7 @@ struct Pgrp
 	int	nmtab;			/* highest active mount table entry, +1 */
 	QLock	debug;			/* single access via devproc.c */
 	Mtab	*mtab;
+	Proc	*rendhash[RENDHASH];	/* Rendezvous tag hash */
 };
 
 struct Egrp
@@ -437,6 +441,7 @@ enum
 	Wakeme,
 	Broken,
 	Stopped,
+	Rendezvous,
 };
 
 /*
@@ -499,6 +504,10 @@ struct Proc
 	int 	hasspin;		/* I hold a spin lock */
 	int	newtlb;			/* Pager has touched my tables so I must flush */
 	int	procctl;		/* Control for /proc debugging */
+
+	ulong	rendtag;		/* Tag for rendezvous */ 
+	ulong	rendval;		/* Value for rendezvous */
+	Proc	*rendhash;		/* Hash list for tag values */
 	/*
 	 *  machine specific MMU goo
 	 */
diff --git a/port/proc.c b/port/proc.c
index e16161a455a8a17fb110fda8239c7a71671ae12f..bd5d0c6d9deb56ed0211542ec5fbc0d66cd57cdf 100644
--- a/port/proc.c
+++ b/port/proc.c
@@ -41,6 +41,7 @@ char *statename[]={	/* BUG: generate automatically */
 	"Wakeme",
 	"Broken",
 	"Stopped",
+	"Rendez",
 };
 
 /*
@@ -390,6 +391,7 @@ postnote(Proc *p, int dolock, char *n, int flag)
 	KMap *k;
 	int s;
 	Rendez *r;
+	Proc *d, **l;
 
 	SET(k);
 	USED(k);
@@ -436,6 +438,23 @@ postnote(Proc *p, int dolock, char *n, int flag)
 		unlock(r);
 		splx(s);
 	}
+	if(p->state == Rendezvous) {
+		lock(p->pgrp);
+		if(p->state == Rendezvous) {
+			p->rendval = 0;
+			l = &REND(p->pgrp, p->rendtag);
+			for(d = *l; d; d = d->rendhash) {
+				if(d == p) {
+					*l = p->rendhash;
+					break;
+				}
+				l = &d->rendhash;
+			}
+			ready(p);
+		}
+		unlock(p->pgrp);
+	}
+
 	return 1;
 }
 
diff --git a/port/sysproc.c b/port/sysproc.c
index e1be1c56bcd6ca74fdd632a66c0716fac30a6239..6ad3db1c8a4681af16b762fbdae767ff843fcf3a 100644
--- a/port/sysproc.c
+++ b/port/sysproc.c
@@ -562,3 +562,46 @@ sysbrk_(ulong *arg)
 {
 	return ibrk(arg[0], BSEG);
 }
+
+long
+sysrendezvous(ulong *arg)
+{
+	Proc *p, *d, **l;
+	int s, tag;
+	ulong val;
+
+	tag = arg[0];
+	l = &REND(u->p->pgrp, tag);
+
+	lock(u->p->pgrp);
+	for(p = *l; p; p = p->rendhash) {
+		if(p->rendtag == tag) {
+			*l = p->rendhash;
+			val = p->rendval;
+			p->rendval = arg[1];
+
+			if(p->state != Rendezvous)
+				panic("rendezvous");
+			ready(p);
+			unlock(u->p->pgrp);
+			return val;	
+		}
+		l = &p->rendhash;
+	}
+
+	/* Going to sleep here */
+	p = u->p;
+	p->rendtag = tag;
+	p->rendval = arg[1];
+	p->rendhash = *l;
+	*l = p;
+
+	unlock(p->pgrp);
+
+	s = splhi();
+	u->p->state = Rendezvous;
+	sched();
+	splx(s);
+
+	return u->p->rendval;
+}
diff --git a/port/systab.h b/port/systab.h
index 483f3c2fa678ef93538ded8d913ae40a3aa0ebfd..6ab3e64ee5f0d94f12b8f2f41a0c26355fc42f22 100644
--- a/port/systab.h
+++ b/port/systab.h
@@ -8,6 +8,7 @@ Syscall	sysfstat, sysfwstat, sysgetpid, sysmount, sysnoted;
 Syscall	sysnotify, sysopen, syspipe, sysr1, sysread, sysremove, sysseek;
 Syscall syssleep, sysstat, syswait, syswrite, syswstat, sysalarm, syssegbrk;
 Syscall syssegattach, syssegdetach, syssegfree, syssegflush;
+Syscall sysrendezvous;
 
 Syscall *systab[]={
 	[SYSR1]		sysr1,
@@ -44,4 +45,5 @@ Syscall *systab[]={
 	[SEGDETACH]	syssegdetach,
 	[SEGFREE]	syssegfree,
 	[SEGFLUSH]	syssegflush,
+	[RENDEZVOUS]	sysrendezvous,
 };
diff --git a/power/boot.c b/power/boot.c
index 7d2dd66dae35facd42c95980d3e635d3fee9552b..51b6f776ccf0433455947cd2d6597113c6850a85 100644
--- a/power/boot.c
+++ b/power/boot.c
@@ -485,7 +485,6 @@ error(char *s)
  *  prompt and get input
  */
 int
-int
 outin(char *prompt, char *def, int len)
 {
 	int n;
diff --git a/power/devhotrod.c b/power/devhotrod.c
index 6a48cbb346b7214a4cc91618c168e0ad62dfb431..9ef6e1f74f68614d79a06bde53fee53f79387e92 100644
--- a/power/devhotrod.c
+++ b/power/devhotrod.c
@@ -13,7 +13,6 @@
 /*
  * If defined, ENABMEMTEST causes memory test to be run at device open
  */
-#define	ENABMEMTEST
 #ifdef	ENABMEMTEST
 void	mem(Hot*, ulong*, ulong);
 #define	NTESTBUF	256
@@ -22,6 +21,7 @@ ulong	testbuf[NTESTBUF];
 /*
  * If defined, ENABBUSTEST causes bus error diagnostic to be run at device open
  */
+#define	ENABBUSTEST
 
 /*
  * If 1, ENABCKSUM causes data transfers to have checksums
@@ -224,8 +224,9 @@ hotrodopen(Chan *c, int omode)
 		 */
 		mp = &u->khot;
 		mp->cmd = Ubus;
-		hmp = hotsend(hp, &((User*)(u->p->upage->pa|KZERO))->khot, 0);
+		hmp = hotsend(hp, &((User*)(u->p->upage->pa|KZERO))->khot);
 		hotwait(hmp);
+for(;;) ;
 #endif
 	}
 	c->mode = openmode(omode);