Some enhancements and bug fix.

     -  Define option FORCECONSPEED to force the serial console to
        be CONSPEED.  I've run into a lot of boards in which
        the detect for prior speed doesn't work and ends up with
        broken console since it is at the wrong speed.
     -  If a serial port is marked as a console, but console=vidconsole
        and if the serial ports doesn't exist it will be probed and
        attached at a 8250 chip.  Then writes to that will freeze the
        system.
     -  Add an option flags 0x400000 to mark this as a potential
        comconsole in-case the one flaged with 0x10 does not exist
        in the system.

This makes it easier to deploy on systems with one or two serial ports.

Obtained from:	IronPort

4 files changed, 81 insertions, 49 deletions

diff --git a/share/man/man4/sio.4 b/share/man/man4/sio.4
index 864714c..7905401 100644
--- a/share/man/man4/sio.4
+++ b/share/man/man4/sio.4
@@ -178,6 +178,8 @@ minor number of master port
 PPS timestamping on CTS instead of DCD
 .It 0x20000
 device is assumed to use a 16650A-type (extended FIFO) chip
+.It 0x400000
+If no comconsole found then mark as a comconsole
 .El
 .Pp
 Minor numbering:
diff --git a/sys/conf/NOTES b/sys/conf/NOTES
index 1d99f5d..0965f8b 100644
--- a/sys/conf/NOTES
+++ b/sys/conf/NOTES
@@ -1466,6 +1466,8 @@ options 	COM_ESP			# Code for Hayes ESP.
 options 	COM_MULTIPORT		# Code for some cards with shared IRQs.
 options 	CONSPEED=115200		# Speed for serial console
 					# (default 9600).
+options 	FORCECONSPEED		# no matter what use CONSPEED for
+					# console.
 
 # `flags' specific to sio(4).  See below for flags used by both sio(4) and
 # uart(4).
diff --git a/sys/conf/options b/sys/conf/options
index 2191fe7..bb2841a 100644
--- a/sys/conf/options
+++ b/sys/conf/options
@@ -519,6 +519,7 @@ BKTR_NEW_MSP34XX_DRIVER		opt_bktr.h
 # options for serial support
 COM_ESP			opt_sio.h
 COM_MULTIPORT		opt_sio.h
+FORCECONSPEED		opt_sio.h
 BREAK_TO_DEBUGGER	opt_comconsole.h
 ALT_BREAK_TO_DEBUGGER	opt_comconsole.h
 
diff --git a/sys/dev/sio/sio.c b/sys/dev/sio/sio.c
index 192973d..0cd3557 100644
--- a/sys/dev/sio/sio.c
+++ b/sys/dev/sio/sio.c
@@ -123,6 +123,7 @@ __FBSDID("$FreeBSD$");
 #define	COM_PPSCTS(flags)	((flags) & 0x10000)
 #define	COM_ST16650A(flags)	((flags) & 0x20000)
 #define	COM_TI16754(flags)	((flags) & 0x200000)
+#define	COM_ALTCONSOLE(flags)	((flags) & 0x400000)
 
 #define	sio_getreg(com, off) \
 	(bus_space_read_1((com)->bst, (com)->bsh, (off)))
@@ -749,7 +750,7 @@ sioprobe(dev, xrid, rclk, noprobe)
 		sio_setreg(com, com_cfcr, CFCR_8BITS);
 		mtx_unlock_spin(&sio_lock);
 		bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
-		if (iobase == siocniobase)
+		if (comconsole != -1 && iobase == siocniobase)
 			result = 0;
 		if (result != 0) {
 			device_set_softc(dev, NULL);
@@ -795,6 +796,7 @@ sioprobe(dev, xrid, rclk, noprobe)
 
 	mtx_unlock_spin(&sio_lock);
 
+	result = 0;
 	irqs = irqmap[1] & ~irqmap[0];
 	if (bus_get_resource(idev, SYS_RES_IRQ, 0, &xirq, NULL) == 0 &&
 	    ((1 << xirq) & irqs) == 0) {
@@ -804,14 +806,14 @@ sioprobe(dev, xrid, rclk, noprobe)
 		printf(
 		"sio%d: port may not be enabled\n",
 		    device_get_unit(dev));
+		result = ENXIO;
 	}
 	if (bootverbose)
 		printf("sio%d: irq maps: %#x %#x %#x %#x\n",
 		    device_get_unit(dev),
 		    irqmap[0], irqmap[1], irqmap[2], irqmap[3]);
 
-	result = 0;
-	for (fn = 0; fn < sizeof failures; ++fn)
+	for (fn = 0; result == 0 && fn < sizeof failures; ++fn)
 		if (failures[fn]) {
 			sio_setreg(com, com_mcr, 0);
 			result = ENXIO;
@@ -826,7 +828,7 @@ sioprobe(dev, xrid, rclk, noprobe)
 			break;
 		}
 	bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
-	if (iobase == siocniobase)
+	if (comconsole != -1 && iobase == siocniobase)
 		result = 0;
 	if (result != 0) {
 		device_set_softc(dev, NULL);
@@ -2814,6 +2816,9 @@ siocngetspeed(iobase, rclk)
 	u_char  cfcr;
 
 	cfcr = inb(iobase + com_cfcr);
+	outb(iobase + com_cfcr, 0x0e);
+	if (inb(iobase + com_cfcr) != 0x0e)
+		return (0);
 	outb(iobase + com_cfcr, CFCR_DLAB | cfcr);
 
 	dlbl = inb(iobase + com_dlbl);
@@ -2826,7 +2831,12 @@ siocngetspeed(iobase, rclk)
 	/* XXX there should be more sanity checking. */
 	if (divisor == 0)
 		return (CONSPEED);
+
+#ifdef FORCECONSPEED
+	return (CONSPEED);
+#else
 	return (rclk / (16UL * divisor));
+#endif
 }
 
 #endif
@@ -2907,7 +2917,7 @@ siocnprobe(cp)
 	speed_t			boot_speed;
 	u_char			cfcr;
 	u_int			divisor;
-	int			s, unit;
+	int			s, unit, check_flags;
 	struct siocnstate	sp;
 
 	/*
@@ -2926,28 +2936,42 @@ siocnprobe(cp)
 	 */
 	cp->cn_pri = CN_DEAD;
 
-	for (unit = 0; unit < 16; unit++) { /* XXX need to know how many */
-		int flags;
+	siocniobase = 0;
+	for(check_flags = 1; check_flags >= 0 && !siocniobase; check_flags--) {
+		for (unit = 0; unit < 16; unit++) { /* XXX need to know how 
+						       many */
+			int flags;
 
-		if (resource_disabled("sio", unit))
-			continue;
-		if (resource_int_value("sio", unit, "flags", &flags))
-			continue;
-		if (COM_CONSOLE(flags) || COM_DEBUGGER(flags)) {
-			int port;
-			Port_t iobase;
-
-			if (resource_int_value("sio", unit, "port", &port))
+			if (resource_disabled("sio", unit))
+				continue;
+			if (resource_int_value("sio", unit, "flags", &flags))
 				continue;
-			iobase = port;
-			s = spltty();
-			if (boothowto & RB_SERIAL) {
-				boot_speed =
-				    siocngetspeed(iobase, comdefaultrclk);
-				if (boot_speed)
-					comdefaultrate = boot_speed;
+
+			if (!check_flags && COM_ALTCONSOLE(flags) 
+			    && !siocniobase){
+				flags |= 0x10;
 			}
 
+			if (COM_CONSOLE(flags) || COM_DEBUGGER(flags)) {
+				int port;
+				Port_t iobase;
+
+				if (resource_int_value("sio", unit, "port",
+				    &port))
+					continue;
+				iobase = port;
+				s = spltty();
+				if (boothowto & RB_SERIAL) {
+					boot_speed = siocngetspeed(iobase, 
+					    comdefaultrclk);
+					if (boot_speed)
+						comdefaultrate = boot_speed;
+					else {
+						splx(s);
+						continue;
+					}
+				}
+
 			/*
 			 * Initialize the divisor latch.  We can't rely on
 			 * siocnopen() to do this the first time, since it 
@@ -2957,34 +2981,37 @@ siocnprobe(cp)
 			 * need to set the speed in hardware so that
 			 * switching it later is null.
 			 */
-			cfcr = inb(iobase + com_cfcr);
-			outb(iobase + com_cfcr, CFCR_DLAB | cfcr);
-			divisor = siodivisor(comdefaultrclk, comdefaultrate);
-			outb(iobase + com_dlbl, divisor & 0xff);
-			outb(iobase + com_dlbh, divisor >> 8);
-			outb(iobase + com_cfcr, cfcr);
-
-			siocnopen(&sp, iobase, comdefaultrate);
-
-			splx(s);
-			if (COM_CONSOLE(flags) && !COM_LLCONSOLE(flags)) {
-				siocnset(cp, unit);
-				cp->cn_pri = COM_FORCECONSOLE(flags)
-					     || boothowto & RB_SERIAL
-					     ? CN_REMOTE : CN_NORMAL;
-				siocniobase = iobase;
-				siocnunit = unit;
-			}
-			if (COM_DEBUGGER(flags)) {
-				printf("sio%d: gdb debugging port\n", unit);
-				siogdbiobase = iobase;
-				siogdbunit = unit;
+				cfcr = inb(iobase + com_cfcr);
+				outb(iobase + com_cfcr, CFCR_DLAB | cfcr);
+				divisor = siodivisor(comdefaultrclk, comdefaultrate);
+				outb(iobase + com_dlbl, divisor & 0xff);
+				outb(iobase + com_dlbh, divisor >> 8);
+				outb(iobase + com_cfcr, cfcr);
+
+				siocnopen(&sp, iobase, comdefaultrate);
+
+				splx(s);
+				if (!siocniobase && COM_CONSOLE(flags)
+				    && !COM_LLCONSOLE(flags)) {
+					siocnset(cp, unit);
+					cp->cn_pri = COM_FORCECONSOLE(flags)
+						|| boothowto & RB_SERIAL
+						? CN_REMOTE : CN_NORMAL;
+					siocniobase = iobase;
+					siocnunit = unit;
+				}
+				if (COM_DEBUGGER(flags)) {
+					printf("sio%d: gdb debugging port\n",
+					    unit);
+					siogdbiobase = iobase;
+					siogdbunit = unit;
 #if DDB > 0
-				siocnset(&gdbconsdev, unit);
-				gdb_arg = &gdbconsdev;
-				gdb_getc = siocngetc;
-				gdb_putc = siocnputc;
+					siocnset(&gdbconsdev, unit);
+					gdb_arg = &gdbconsdev;
+					gdb_getc = siocngetc;
+					gdb_putc = siocnputc;
 #endif
+				}
 			}
 		}
 	}