Re-commit Exar XR17V35x serial port support previously backed out:

The Exar XR17V354 has 4 ports that have a 256-byte FIFO, use a
frequency of 125Mhz, and have a unique sleep register.  A custom
interrupt handler is setup in puc for these ports so it can check a
register which reports which ports triggered the interrupt, rather
than having to run comintr for every port every time.

To avoid probing for these ports in com_attach_subr which requires
access to registers that may be reserved on certain platforms, pass
the sc_uarttype from com_puc_attach since the port type is already
known based on the puc device vendor/id.

Input from kettenis, tested in snaps

7 files changed, 79 insertions, 16 deletions

diff --git a/sys/dev/ic/com.c b/sys/dev/ic/com.c
index 0659a9d0600..aa67cb359ec 100644
--- a/sys/dev/ic/com.c
+++ b/sys/dev/ic/com.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: com.c,v 1.172 2020/03/09 04:38:46 yasuoka Exp $	*/
+/*	$OpenBSD: com.c,v 1.173 2020/08/14 18:14:11 jcs Exp $	*/
 /*	$NetBSD: com.c,v 1.82.4.1 1996/06/02 09:08:00 mrg Exp $	*/
 
 /*
@@ -306,6 +306,9 @@ comopen(dev_t dev, int flag, int mode, struct proc *p)
 			case COM_UART_TI16750:
 				com_write_reg(sc, com_ier, 0);
 				break;
+			case COM_UART_XR17V35X:
+				com_write_reg(sc, UART_EXAR_SLEEP, 0);
+				break;
 			}
 		}
 
@@ -498,6 +501,9 @@ compwroff(struct com_softc *sc)
 		case COM_UART_TI16750:
 			com_write_reg(sc, com_ier, IER_SLEEP);
 			break;
+		case COM_UART_XR17V35X:
+			com_write_reg(sc, UART_EXAR_SLEEP, 0xff);
+			break;
 		}
 	}
 }
@@ -533,6 +539,9 @@ com_resume(struct com_softc *sc)
 		case COM_UART_TI16750:
 			com_write_reg(sc, com_ier, 0);
 			break;
+		case COM_UART_XR17V35X:
+			com_write_reg(sc, UART_EXAR_SLEEP, 0);
+			break;
 		}
 	}
 
@@ -919,7 +928,7 @@ comstart(struct tty *tp)
 	}
 
 	if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) {
-		u_char buffer[128];	/* largest fifo */
+		u_char buffer[256];	/* largest fifo */
 		int i, n;
 
 		n = q_to_b(&tp->t_outq, buffer,
@@ -1466,6 +1475,11 @@ com_attach_subr(struct com_softc *sc)
 		break;
 #endif
 #endif
+	case COM_UART_XR17V35X:
+		printf(": xr17v35x, 256 byte fifo\n");
+		SET(sc->sc_hwflags, COM_HW_FIFO);
+		sc->sc_fifolen = 256;
+		break;
 	default:
 		panic("comattach: bad fifo type");
 	}
@@ -1473,7 +1487,8 @@ com_attach_subr(struct com_softc *sc)
 #ifdef COM_CONSOLE
 	if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE))
 #endif
-		com_fifo_probe(sc);
+		if (sc->sc_fifolen < 256)
+			com_fifo_probe(sc);
 
 	if (sc->sc_fifolen == 0) {
 		CLR(sc->sc_hwflags, COM_HW_FIFO);
diff --git a/sys/dev/ic/comreg.h b/sys/dev/ic/comreg.h
index 21ea12b4cd9..627f3828389 100644
--- a/sys/dev/ic/comreg.h
+++ b/sys/dev/ic/comreg.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: comreg.h,v 1.19 2018/05/02 13:20:12 kettenis Exp $	*/
+/*	$OpenBSD: comreg.h,v 1.20 2020/08/14 18:14:11 jcs Exp $	*/
 /*	$NetBSD: comreg.h,v 1.8 1996/02/05 23:01:50 scottr Exp $	*/
 
 /*
@@ -182,6 +182,11 @@
 
 #define	COM_NPORTS	8
 
+/* Exar XR17V35X */
+#define UART_EXAR_INT0	0x80
+#define UART_EXAR_SLEEP	0x8b	/* Sleep mode */
+#define UART_EXAR_DVID	0x8d	/* Device identification */
+
 /*
  * WARNING: Serial console is assumed to be at COM1 address
  */
diff --git a/sys/dev/ic/comvar.h b/sys/dev/ic/comvar.h
index 6598cde8bb4..c1a15f5d07f 100644
--- a/sys/dev/ic/comvar.h
+++ b/sys/dev/ic/comvar.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: comvar.h,v 1.57 2018/05/14 19:25:54 kettenis Exp $	*/
+/*	$OpenBSD: comvar.h,v 1.58 2020/08/14 18:14:11 jcs Exp $	*/
 /*	$NetBSD: comvar.h,v 1.5 1996/05/05 19:50:47 christos Exp $	*/
 
 /*
@@ -103,6 +103,7 @@ struct com_softc {
 #define	COM_UART_ST16C654	0x08		/* 64 bytes fifo */
 #define	COM_UART_XR16850	0x10		/* 128 byte fifo */
 #define	COM_UART_OX16C950	0x11		/* 128 byte fifo */
+#define	COM_UART_XR17V35X	0x12		/* 256 byte fifo */
 
 	u_char sc_hwflags;
 #define	COM_HW_NOIEN	0x01
diff --git a/sys/dev/pci/puc.c b/sys/dev/pci/puc.c
index 2123750945a..df680dae7af 100644
--- a/sys/dev/pci/puc.c
+++ b/sys/dev/pci/puc.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: puc.c,v 1.29 2020/03/02 19:45:42 patrick Exp $	*/
+/*	$OpenBSD: puc.c,v 1.30 2020/08/14 18:14:11 jcs Exp $	*/
 /*	$NetBSD: puc.c,v 1.3 1999/02/06 06:29:54 cgd Exp $	*/
 
 /*
@@ -61,6 +61,7 @@
 #include <dev/pci/pcireg.h>
 #include <dev/pci/pcivar.h>
 #include <dev/pci/pucvar.h>
+#include <dev/pci/pcidevs.h>
 
 #include <dev/ic/comreg.h>
 #include <dev/ic/comvar.h>
@@ -80,6 +81,7 @@ int	puc_pci_detach(struct device *, int);
 const char *puc_pci_intr_string(struct puc_attach_args *);
 void	*puc_pci_intr_establish(struct puc_attach_args *, int,
     int (*)(void *), void *, char *);
+int	puc_pci_xr17v35x_intr(void *arg);
 
 struct cfattach puc_pci_ca = {
 	sizeof(struct puc_pci_softc), puc_pci_match,
@@ -127,7 +129,17 @@ puc_pci_intr_establish(struct puc_attach_args *paa, int type,
 {
 	struct puc_pci_softc *sc = paa->puc;
 	struct puc_softc *psc = &sc->sc_psc;
-	
+
+	if (psc->sc_xr17v35x) {
+		psc->sc_ports[paa->port].real_intrhand = func;
+		psc->sc_ports[paa->port].real_intrhand_arg = arg;
+		if (paa->port == 0)
+			psc->sc_ports[paa->port].intrhand =
+			    pci_intr_establish(sc->pc, sc->ih, type,
+			    puc_pci_xr17v35x_intr, sc, name);
+		return (psc->sc_ports[paa->port].real_intrhand);
+	}
+
 	psc->sc_ports[paa->port].intrhand =
 	    pci_intr_establish(sc->pc, sc->ih, type, func, arg, name);
 
@@ -148,6 +160,10 @@ puc_pci_attach(struct device *parent, struct device *self, void *aux)
 	sc->sc_desc = puc_find_description(PCI_VENDOR(pa->pa_id),
 	    PCI_PRODUCT(pa->pa_id), PCI_VENDOR(subsys), PCI_PRODUCT(subsys));
 
+	if (PCI_VENDOR(pa->pa_id) == PCI_VENDOR_EXAR &&
+	    PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_EXAR_XR17V354)
+		sc->sc_xr17v35x = 1;
+
 	puc_print_ports(sc->sc_desc);
 
 	for (i = 0; i < PUC_NBARS; i++) {
@@ -328,7 +344,6 @@ puc_find_description(u_int16_t vend, u_int16_t prod,
 const char *
 puc_port_type_name(int type)
 {
-
 	if (PUC_IS_COM(type))
 		return "com";
 	if (PUC_IS_LPT(type))
@@ -357,3 +372,22 @@ puc_print_ports(const struct puc_device_description *desc)
 	}
 	printf("\n");
 }
+
+int
+puc_pci_xr17v35x_intr(void *arg)
+{
+	struct puc_pci_softc *sc = arg;
+	struct puc_softc *psc = &sc->sc_psc;
+	int ports, i;
+
+	ports = bus_space_read_1(psc->sc_bar_mappings[0].t,
+	    psc->sc_bar_mappings[0].h, UART_EXAR_INT0);
+
+	for (i = 0; i < 8; i++) {
+		if ((ports & (1 << i)) && psc->sc_ports[i].real_intrhand)
+			(*(psc->sc_ports[i].real_intrhand))(
+			    psc->sc_ports[i].real_intrhand_arg);
+	}
+
+	return (1);
+}
diff --git a/sys/dev/pci/pucdata.c b/sys/dev/pci/pucdata.c
index 0011d0ac2f7..51a41fa0e43 100644
--- a/sys/dev/pci/pucdata.c
+++ b/sys/dev/pci/pucdata.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pucdata.c,v 1.111 2020/01/05 01:07:59 jsg Exp $	*/
+/*	$OpenBSD: pucdata.c,v 1.112 2020/08/14 18:14:11 jcs Exp $	*/
 /*	$NetBSD: pucdata.c,v 1.6 1999/07/03 05:55:23 cgd Exp $	*/
 
 /*
@@ -2083,10 +2083,10 @@ const struct puc_device_description puc_devs[] = {
 	    {   PCI_VENDOR_EXAR, PCI_PRODUCT_EXAR_XR17V354,	0, 0 },
 	    {   0xffff, 0xffff,					0, 0 },
 	    {
-		{ PUC_PORT_COM_MUL8, 0x10, 0x0000 },
-		{ PUC_PORT_COM_MUL8, 0x10, 0x0400 },
-		{ PUC_PORT_COM_MUL8, 0x10, 0x0800 },
-		{ PUC_PORT_COM_MUL8, 0x10, 0x0C00 },
+		{ PUC_PORT_COM_XR17V35X, 0x10, 0x0000 },
+		{ PUC_PORT_COM_XR17V35X, 0x10, 0x0400 },
+		{ PUC_PORT_COM_XR17V35X, 0x10, 0x0800 },
+		{ PUC_PORT_COM_XR17V35X, 0x10, 0x0C00 },
 	    },
 	},
 
diff --git a/sys/dev/pci/pucvar.h b/sys/dev/pci/pucvar.h
index da3d0784d9b..0756dd27650 100644
--- a/sys/dev/pci/pucvar.h
+++ b/sys/dev/pci/pucvar.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pucvar.h,v 1.16 2018/05/02 19:11:01 phessler Exp $	*/
+/*	$OpenBSD: pucvar.h,v 1.17 2020/08/14 18:14:11 jcs Exp $	*/
 /*	$NetBSD: pucvar.h,v 1.2 1999/02/06 06:29:54 cgd Exp $	*/
 
 /*
@@ -60,7 +60,7 @@ struct puc_port_type {
 		PUC_PORT_COM_MUL8,
 		PUC_PORT_COM_MUL10,
 		PUC_PORT_COM_MUL128,
-		PUC_PORT_COM_125MHZ,
+		PUC_PORT_COM_XR17V35X,
 	} type;
 	u_int32_t	freq;
 };
@@ -72,6 +72,7 @@ static const struct puc_port_type puc_port_types[] = {
 	{ PUC_PORT_COM_MUL8,	COM_FREQ * 8	},
 	{ PUC_PORT_COM_MUL10,	COM_FREQ * 10	},
 	{ PUC_PORT_COM_MUL128,	COM_FREQ * 128	},
+	{ PUC_PORT_COM_XR17V35X, 125000000	},
 };
 
 #define PUC_IS_LPT(type)	((type) == PUC_PORT_LPT)
@@ -117,7 +118,11 @@ struct puc_softc {
 		struct device   *dev;
 		/* filled in by port attachments */
 		void	*intrhand;
+		int	(*real_intrhand)(void *);
+		void	*real_intrhand_arg;
 	} sc_ports[PUC_MAX_PORTS];
+
+	int			sc_xr17v35x;
 };
 
 const struct puc_device_description *
diff --git a/sys/dev/puc/com_puc.c b/sys/dev/puc/com_puc.c
index 33a434fba23..a398427a83f 100644
--- a/sys/dev/puc/com_puc.c
+++ b/sys/dev/puc/com_puc.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: com_puc.c,v 1.24 2018/04/15 00:10:59 jcs Exp $	*/
+/*	$OpenBSD: com_puc.c,v 1.25 2020/08/14 18:14:11 jcs Exp $	*/
 
 /*
  * Copyright (c) 1997 - 1999, Jason Downs.  All rights reserved.
@@ -109,6 +109,9 @@ com_puc_attach(parent, self, aux)
 			break;
 		}
 
+	if (pa->type == PUC_PORT_COM_XR17V35X)
+		sc->sc_uarttype = COM_UART_XR17V35X;
+
 	com_attach_subr(sc);
 }