diff --git a/sys/dev/puc/puc.c b/sys/dev/puc/puc.c
index 18d2fbabc0f5..fedf9bb073cf 100644
--- a/sys/dev/puc/puc.c
+++ b/sys/dev/puc/puc.c
@@ -130,6 +130,35 @@ puc_port_bar_index(struct puc_softc *sc, int bar)
 	return (i);
 }
 
+static int
+puc_probe_ilr(struct puc_softc *sc, struct resource *res)
+{
+	u_char t1, t2;
+	int i;
+
+	switch (sc->sc_desc->ilr_type) {
+	case PUC_ILR_TYPE_DIGI:
+		sc->ilr_st = rman_get_bustag(res);
+		sc->ilr_sh = rman_get_bushandle(res);
+		for (i = 0; i < 2; i++) {
+			t1 = bus_space_read_1(sc->ilr_st, sc->ilr_sh,
+			    sc->sc_desc->ilr_offset[i]);
+			t1 = ~t1;
+			bus_space_write_1(sc->ilr_st, sc->ilr_sh,
+			    sc->sc_desc->ilr_offset[i], t1);
+			t2 = bus_space_read_1(sc->ilr_st, sc->ilr_sh,
+			    sc->sc_desc->ilr_offset[i]);
+			if (t2 == t1)
+				return (0);
+		}
+		return (1);
+
+	default:
+		break;
+	}
+	return (0);
+}
+
 int
 puc_attach(device_t dev, const struct puc_device_description *desc)
 {
@@ -195,6 +224,14 @@ puc_attach(device_t dev, const struct puc_device_description *desc)
 		}
 		sc->sc_bar_mappings[bidx].type = type;
 		sc->sc_bar_mappings[bidx].res = res;
+
+		if (sc->sc_desc->ilr_type != PUC_ILR_TYPE_NONE) {
+			sc->ilr_enabled = puc_probe_ilr(sc, res);
+			if (sc->ilr_enabled)
+				device_printf(dev, "ILR enabled\n");
+			else
+				device_printf(dev, "ILR disabled\n");
+		}
 #ifdef PUC_DEBUG
 		printf("%s rid %d bst %x, start %x, end %x\n",
 		    (type == SYS_RES_MEMORY) ? "memory" : "port", rid,
@@ -307,22 +344,47 @@ puc_attach(device_t dev, const struct puc_device_description *desc)
 	return (0);
 }
 
+static u_int32_t
+puc_ilr_read(struct puc_softc *sc)
+{
+	u_int32_t mask;
+	int i;
+
+	mask = 0;
+	switch (sc->sc_desc->ilr_type) {
+	case PUC_ILR_TYPE_DIGI:
+		for (i = 1; i >= 0; i--) {
+			mask = (mask << 8) | (bus_space_read_1(sc->ilr_st,
+			    sc->ilr_sh, sc->sc_desc->ilr_offset[i]) & 0xff);
+		}
+		break;
+
+	default:
+		mask = 0xffffffff;
+		break;
+	}
+	return (mask);
+}
+
 /*
- * This is just a brute force interrupt handler. It just calls all the
- * registered handlers sequencially.
- *
- * Later on we should maybe have a different handler for boards that can
- * tell us which device generated the interrupt.
+ * This is an interrupt handler. For boards that can't tell us which
+ * device generated the interrupt it just calls all the registered
+ * handlers sequencially, but for boards that can tell us which
+ * device(s) generated the interrupt it calls only handlers for devices
+ * that actually generated the interrupt.
  */
 static void
 puc_intr(void *arg)
 {
 	int i;
+	u_int32_t ilr_mask;
 	struct puc_softc *sc;
 
 	sc = (struct puc_softc *)arg;
+	ilr_mask = sc->ilr_enabled ? puc_ilr_read(sc) : 0xffffffff;
 	for (i = 0; i < PUC_MAX_PORTS; i++)
-		if (sc->sc_ports[i].ihand != NULL)
+		if (sc->sc_ports[i].ihand != NULL &&
+		    ((ilr_mask >> i) & 0x00000001))
 			(sc->sc_ports[i].ihand)(sc->sc_ports[i].ihandarg);
 }
 
diff --git a/sys/dev/puc/pucdata.c b/sys/dev/puc/pucdata.c
index e55621502b6e..7e65aa775a15 100644
--- a/sys/dev/puc/pucdata.c
+++ b/sys/dev/puc/pucdata.c
@@ -1000,23 +1000,24 @@ const struct puc_device_description puc_devices[] = {
 	    {	0xb00c, 0x091c, 0,	0	},
 	    {   0xffff, 0xffff, 0,      0       },
 	    {
-		{ PUC_PORT_TYPE_COM, 0x10, 0x00, COM_FREQ * 4 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x08, COM_FREQ * 4 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x10, COM_FREQ * 4 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x18, COM_FREQ * 4 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x20, COM_FREQ * 4 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x28, COM_FREQ * 4 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x30, COM_FREQ * 4 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x38, COM_FREQ * 4 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x40, COM_FREQ * 4 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x48, COM_FREQ * 4 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x50, COM_FREQ * 4 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x58, COM_FREQ * 4 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x60, COM_FREQ * 4 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x68, COM_FREQ * 4 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x70, COM_FREQ * 4 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x78, COM_FREQ * 4 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x00, COM_FREQ },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x08, COM_FREQ },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x10, COM_FREQ },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x18, COM_FREQ },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x20, COM_FREQ },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x28, COM_FREQ },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x30, COM_FREQ },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x38, COM_FREQ },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x40, COM_FREQ },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x48, COM_FREQ },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x50, COM_FREQ },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x58, COM_FREQ },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x60, COM_FREQ },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x68, COM_FREQ },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x70, COM_FREQ },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x78, COM_FREQ },
 	    },
+	    PUC_ILR_TYPE_DIGI, { 0x07, 0x47 },
 	},
 
 	{   "IC Book Labs Dreadnought x16 Pro",
@@ -1024,23 +1025,24 @@ const struct puc_device_description puc_devices[] = {
 	    {   0xb00c, 0x081c, 0,      0       },
 	    {   0xffff, 0xffff, 0,      0       },
 	    {
-		{ PUC_PORT_TYPE_COM, 0x10, 0x00, COM_FREQ * 8 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x08, COM_FREQ * 8 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x10, COM_FREQ * 8 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x18, COM_FREQ * 8 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x20, COM_FREQ * 8 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x28, COM_FREQ * 8 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x30, COM_FREQ * 8 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x38, COM_FREQ * 8 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x40, COM_FREQ * 8 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x48, COM_FREQ * 8 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x50, COM_FREQ * 8 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x58, COM_FREQ * 8 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x60, COM_FREQ * 8 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x68, COM_FREQ * 8 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x70, COM_FREQ * 8 },
-		{ PUC_PORT_TYPE_COM, 0x10, 0x78, COM_FREQ * 8 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x00, COM_FREQ * 8, 0x200000 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x08, COM_FREQ * 8, 0x200000 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x10, COM_FREQ * 8, 0x200000 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x18, COM_FREQ * 8, 0x200000 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x20, COM_FREQ * 8, 0x200000 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x28, COM_FREQ * 8, 0x200000 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x30, COM_FREQ * 8, 0x200000 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x38, COM_FREQ * 8, 0x200000 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x40, COM_FREQ * 8, 0x200000 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x48, COM_FREQ * 8, 0x200000 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x50, COM_FREQ * 8, 0x200000 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x58, COM_FREQ * 8, 0x200000 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x60, COM_FREQ * 8, 0x200000 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x68, COM_FREQ * 8, 0x200000 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x70, COM_FREQ * 8, 0x200000 },
+		{ PUC_PORT_TYPE_COM, 0x10, 0x78, COM_FREQ * 8, 0x200000 },
 	    },
+	    PUC_ILR_TYPE_DIGI, { 0x07, 0x47 },
 	},
 
 	{ 0 }
diff --git a/sys/dev/puc/pucvar.h b/sys/dev/puc/pucvar.h
index fcbb0eb86b66..9bb3928340de 100644
--- a/sys/dev/puc/pucvar.h
+++ b/sys/dev/puc/pucvar.h
@@ -80,6 +80,8 @@ struct puc_device_description {
 		u_int	serialfreq;
 		u_int	flags;
 	} ports[PUC_MAX_PORTS];
+	uint32_t	ilr_type;
+	uint32_t	ilr_offset[2];
 };
 
 #define	PUC_REG_VEND		0
@@ -91,6 +93,10 @@ struct puc_device_description {
 #define	PUC_PORT_TYPE_COM	1
 #define	PUC_PORT_TYPE_LPT	2
 
+/* Interrupt Latch Register (ILR) types */
+#define	PUC_ILR_TYPE_NONE	0
+#define	PUC_ILR_TYPE_DIGI	1
+
 #define	PUC_FLAGS_MEMORY	0x0001		/* Use memory mapped I/O. */
 
 #define	PUC_PORT_VALID(desc, port) \
@@ -126,6 +132,9 @@ struct puc_softc {
 	int			irqrid;
 	struct resource		*irqres;
 	void			*intr_cookie;
+	int			ilr_enabled;
+	bus_space_tag_t		ilr_st;
+	bus_space_handle_t	ilr_sh;
 
 	struct {
 		int		used;
diff --git a/sys/dev/sio/sio.c b/sys/dev/sio/sio.c
index f5e7363601eb..dcfd46a781f7 100644
--- a/sys/dev/sio/sio.c
+++ b/sys/dev/sio/sio.c
@@ -120,6 +120,7 @@
 #define COM_C_IIR_TXRDYBUG	(0x80000)
 #define COM_IIR_TXRDYBUG(flags)	((flags) & COM_C_IIR_TXRDYBUG)
 #define COM_NOSCR(flags)	((flags) & 0x100000)
+#define COM_TI16754(flags)	((flags) & 0x200000)
 #define	COM_FIFOSIZE(flags)	(((flags) & 0xff000000) >> 24)
 
 #define	sio_getreg(com, off) \
@@ -604,6 +605,33 @@ sioprobe(dev, xrid, rclk, noprobe)
 	mtx_lock_spin(&sio_lock);
 /* EXTRA DELAY? */
 
+	/*
+	 * For the TI16754 chips set prescaler to 1 (4 is often the
+	 * default after-reset value), otherwise it's impossible to
+	 * get highest baudrates.
+	 */
+	if (COM_TI16754(flags)) {
+		u_char t1, t2;
+
+		/* Save LCR */
+		t1 = sio_getreg(com, com_lctl);
+		/* Enable EFR */
+		sio_setreg(com, com_lctl, 0xbf);
+		/* Save EFR */
+		t2 = sio_getreg(com, com_iir);
+		/* Unlock MCR[7] */
+		sio_setreg(com, com_iir, t2 | 0x10);
+		/* Disable EFR */
+		sio_setreg(com, com_lctl, 0);
+		/* Set prescaler to 1 */
+		sio_setreg(com, com_mcr, sio_getreg(com, com_mcr) & 0x7f);
+		/* Enable EFR */
+		sio_setreg(com, com_lctl, 0xbf);
+		/* Restore EFR */
+		sio_setreg(com, com_iir, t2);
+		/* Restore LCR */
+		sio_setreg(com, com_lctl, t1);
+	}
 	/*
 	 * Initialize the speed and the word size and wait long enough to
 	 * drain the maximum of 16 bytes of junk in device output queues.
@@ -731,6 +759,7 @@ sioprobe(dev, xrid, rclk, noprobe)
 	failures[0] = sio_getreg(com, com_cfcr) - CFCR_8BITS;
 	failures[1] = sio_getreg(com, com_ier) - IER_ETXRDY;
 	failures[2] = (sio_getreg(com, com_mcr) & 0x7f) - mcr_image;
+	failures[2] = sio_getreg(com, com_mcr) - mcr_image;
 	DELAY(10000);		/* Some internal modems need this time */
 	irqmap[1] = isa_irq_pending();
 	failures[4] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_TXRDY;
@@ -1007,6 +1036,9 @@ sioattach(dev, xrid, rclk)
 				com->st16650a = 1;
 				com->tx_fifo_size = 32;
 				printf(" ST16650A");
+			} else if (COM_TI16754(flags)) {
+				com->tx_fifo_size = 64;
+				printf(" TI16754");
 			} else {
 				com->tx_fifo_size = COM_FIFOSIZE(flags);
 				printf(" 16550A");
@@ -1019,7 +1051,7 @@ sioattach(dev, xrid, rclk)
 				break;
 			}
 #endif
-		if (!com->st16650a) {
+		if (!com->st16650a && !COM_TI16754(flags)) {
 			if (!com->tx_fifo_size)
 				com->tx_fifo_size = 16;
 			else