--- Net2/arch/i386/isa/com.c	2018/04/24 18:07:10	1.1.1.3
+++ Net2/arch/i386/isa/com.c	2018/04/24 18:12:06	1.1.1.4
@@ -31,8 +31,18 @@
  * SUCH DAMAGE.
  *
  *	@(#)com.c	7.5 (Berkeley) 5/16/91
+ *
+ * PATCHES MAGIC                LEVEL   PATCH THAT GOT US HERE
+ * --------------------         -----   ----------------------
+ * CURRENT PATCH LEVEL:         4       00079
+ * --------------------         -----   ----------------------
+ *
+ * 23 Sep 92	Rodney W. Grimes	Fix SILO overflow on 16550 UARTS
+ * 30 Aug 92	Poul-Henning Kamp	Stabilize SLIP on lossy lines/UARTS
+ * 09 Aug 92	Christoph Robitschko	Correct minor number on com ports
+ * 10 Feb 93	Jordan K. Hubbard	Added select code
  */
-static char rcsid[] = "$Header: /var/lib/cvsd/net2/Net2/arch/i386/isa/com.c,v 1.1.1.3 2018/04/24 18:07:10 root Exp $";
+static char rcsid[] = "$Header: /var/lib/cvsd/net2/Net2/arch/i386/isa/com.c,v 1.1.1.4 2018/04/24 18:12:06 root Exp $";
 
 #include "com.h"
 #if NCOM > 0
@@ -51,6 +61,7 @@ static char rcsid[] = "$Header: /var/lib
 #include "uio.h"
 #include "kernel.h"
 #include "syslog.h"
+#include "types.h"
 
 #include "i386/isa/isa_device.h"
 #include "i386/isa/comreg.h"
@@ -108,7 +119,7 @@ extern int kgdb_rate;
 extern int kgdb_debug_init;
 #endif
 
-#define	UNIT(x)		(minor(x)-1)
+#define	UNIT(x)		(minor(x))
 
 comprobe(dev)
 struct isa_device *dev;
@@ -118,7 +129,7 @@ struct isa_device *dev;
 	outb(dev->id_iobase+com_iir, 0);
 	DELAY(100);
 	if ((inb(dev->id_iobase+com_iir) & 0x38) == 0)
-		return(1);
+		return(8);
 	return(0);
 }
 
@@ -131,7 +142,7 @@ struct isa_device *isdp;
 	u_char		unit;
 	int		port = isdp->id_iobase;
 
-	unit = isdp->id_unit - 1;
+	unit = isdp->id_unit;
 	if (unit == comconsole)
 		DELAY(1000);
 	com_addr[unit] = port;
@@ -139,17 +150,17 @@ struct isa_device *isdp;
 	comsoftCAR |= 1 << unit;	/* XXX */
 
 	/* look for a NS 16550AF UART with FIFOs */
-	outb(port+com_fifo, FIFO_ENABLE|FIFO_RCV_RST|FIFO_XMT_RST|FIFO_TRIGGER_14);
+	outb(port+com_fifo, FIFO_ENABLE|FIFO_RCV_RST|FIFO_XMT_RST|FIFO_TRIGGER_4);
 	DELAY(100);
 	if ((inb(port+com_iir) & IIR_FIFO_MASK) == IIR_FIFO_MASK) {
 		com_hasfifo |= 1 << unit;
-		printf(" fifo");
+		printf("com%d: fifo\n", isdp->id_unit);
 	}
 
 	outb(port+com_ier, 0);
 	outb(port+com_mcr, 0 | MCR_IENABLE);
 #ifdef KGDB
-	if (kgdb_dev == makedev(commajor, unit+1)) {
+	if (kgdb_dev == makedev(commajor, unit)) {
 		if (comconsole == unit)
 			kgdb_dev = -1;	/* can't debug over console port */
 		else {
@@ -239,7 +250,7 @@ comclose(dev, flag, mode, p)
 	outb(com+com_cfcr, inb(com+com_cfcr) & ~CFCR_SBREAK);
 #ifdef KGDB
 	/* do not disable interrupts if debugging */
-	if (kgdb_dev != makedev(commajor, unit+1))
+	if (kgdb_dev != makedev(commajor, unit))
 #endif
 	outb(com+com_ier, 0);
 	if (tp->t_cflag&HUPCL || tp->t_state&TS_WOPEN || 
@@ -283,7 +294,7 @@ comintr(unit)
 	register u_char code;
 	register struct tty *tp;
 
-	unit--;
+	unit;
 	com = com_addr[unit];
 	while (1) {
 		code = inb(com+com_iir);
@@ -300,7 +311,7 @@ comintr(unit)
 #define	RCVBYTE() \
 			code = inb(com+com_data); \
 			if ((tp->t_state & TS_ISOPEN) == 0) { \
-				if (kgdb_dev == makedev(commajor, unit+1) && \
+				if (kgdb_dev == makedev(commajor, unit) && \
 				    code == FRAME_END) \
 					kgdb_connect(0); /* trap into kgdb */ \
 			} else \
@@ -359,7 +370,7 @@ comeint(unit, stat, com)
 #ifdef KGDB
 		/* we don't care about parity errors */
 		if (((stat & (LSR_BI|LSR_FE|LSR_PE)) == LSR_PE) &&
-		    kgdb_dev == makedev(commajor, unit+1) && c == FRAME_END)
+		    kgdb_dev == makedev(commajor, unit) && c == FRAME_END)
 			kgdb_connect(0); /* trap into kgdb */
 #endif
 		return;
@@ -368,8 +379,10 @@ comeint(unit, stat, com)
 		c |= TTY_FE;
 	else if (stat & LSR_PE)
 		c |= TTY_PE;
-	else if (stat & LSR_OE)
+	else if (stat & LSR_OE) {			/* 30 Aug 92*/
+		c |= TTY_PE;	/* Ought to have it's own define... */
 		log(LOG_WARNING, "com%d: silo overflow\n", unit);
+	}
 	(*linesw[tp->t_line].l_rint)(c, tp);
 }
 
@@ -503,7 +516,7 @@ comparam(tp, t)
 	outb(com+com_cfcr, cfcr);
 
 	if (com_hasfifo & (1 << unit))
-		outb(com+com_fifo, FIFO_ENABLE | FIFO_TRIGGER_14);
+		outb(com+com_fifo, FIFO_ENABLE | FIFO_TRIGGER_4);
 
 	return(0);
 }
@@ -616,7 +629,7 @@ comcnprobe(cp)
 	/* make sure hardware exists?  XXX */
 
 	/* initialize required fields */
-	cp->cn_dev = makedev(commajor, unit+1);
+	cp->cn_dev = makedev(commajor, unit);
 	cp->cn_tp = &com_tty[unit];
 #ifdef	COMCONSOLE
 	cp->cn_pri = CN_REMOTE;		/* Force a serial port console */
@@ -653,7 +666,7 @@ cominit(unit, rate)
 	outb(com+com_ier, rate >> 8);
 	outb(com+com_cfcr, CFCR_8BITS);
 	outb(com+com_ier, IER_ERXRDY | IER_ETXRDY);
-	outb(com+com_fifo, FIFO_ENABLE|FIFO_RCV_RST|FIFO_XMT_RST|FIFO_TRIGGER_14);
+	outb(com+com_fifo, FIFO_ENABLE|FIFO_RCV_RST|FIFO_XMT_RST|FIFO_TRIGGER_4);
 	stat = inb(com+com_iir);
 	splx(s);
 }
@@ -711,4 +724,45 @@ comcnputc(dev, c)
 	stat = inb(com+com_iir);
 	splx(s);
 }
+
+int
+comselect(dev, rw, p)
+	dev_t dev;
+	int rw;
+	struct proc *p;
+{
+	register struct tty *tp = &com_tty[UNIT(dev)];
+	int nread;
+	int s = spltty();
+        struct proc *selp;
+
+	switch (rw) {
+
+	case FREAD:
+		nread = ttnread(tp);
+		if (nread > 0 || 
+		   ((tp->t_cflag&CLOCAL) == 0 && (tp->t_state&TS_CARR_ON) == 0))
+			goto win;
+		if (tp->t_rsel && (selp = pfind(tp->t_rsel)) && selp->p_wchan == (caddr_t)&selwait)
+			tp->t_state |= TS_RCOLL;
+		else
+			tp->t_rsel = p->p_pid;
+		break;
+
+	case FWRITE:
+		if (RB_LEN(&tp->t_out) <= tp->t_lowat)
+			goto win;
+		if (tp->t_wsel && (selp = pfind(tp->t_wsel)) && selp->p_wchan == (caddr_t)&selwait)
+			tp->t_state |= TS_WCOLL;
+		else
+			tp->t_wsel = p->p_pid;
+		break;
+	}
+	splx(s);
+	return (0);
+  win:
+	splx(s);
+	return (1);
+}
+
 #endif