xref: /dragonfly/sys/dev/serial/sio/sio.c (revision 82ece171)
1 /*-
2  * Copyright (c) 1991 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * $FreeBSD: src/sys/isa/sio.c,v 1.291.2.35 2003/05/18 08:51:15 murray Exp $
34  * $DragonFly: src/sys/dev/serial/sio/sio.c,v 1.28 2005/06/16 21:12:41 dillon Exp $
35  *	from: @(#)com.c	7.5 (Berkeley) 5/16/91
36  *	from: i386/isa sio.c,v 1.234
37  */
38 
39 #include "opt_comconsole.h"
40 #include "opt_compat.h"
41 #include "opt_ddb.h"
42 #include "opt_sio.h"
43 #include "use_pci.h"
44 #ifdef __i386__
45 #include "use_puc.h"
46 #endif
47 #include "use_sio.h"
48 
49 /*
50  * Serial driver, based on 386BSD-0.1 com driver.
51  * Mostly rewritten to use pseudo-DMA.
52  * Works for National Semiconductor NS8250-NS16550AF UARTs.
53  * COM driver, based on HP dca driver.
54  *
55  * Changes for PC-Card integration:
56  *	- Added PC-Card driver table and handlers
57  */
58 #include <sys/param.h>
59 #include <sys/systm.h>
60 #include <sys/reboot.h>
61 #include <sys/malloc.h>
62 #include <sys/tty.h>
63 #include <sys/proc.h>
64 #include <sys/module.h>
65 #include <sys/conf.h>
66 #include <sys/dkstat.h>
67 #include <sys/fcntl.h>
68 #include <sys/interrupt.h>
69 #include <sys/kernel.h>
70 #include <sys/syslog.h>
71 #include <sys/sysctl.h>
72 #include <sys/bus.h>
73 #include <machine/bus_pio.h>
74 #include <machine/bus.h>
75 #include <sys/rman.h>
76 #include <sys/timepps.h>
77 #include <sys/thread2.h>
78 
79 #include <machine/limits.h>
80 
81 #include <bus/isa/isareg.h>
82 #include <bus/isa/isavar.h>
83 #if NPCI > 0
84 #include <bus/pci/pcireg.h>
85 #include <bus/pci/pcivar.h>
86 #endif
87 #if NPUC > 0
88 #include <dev/misc/puc/pucvar.h>
89 #endif
90 #include <machine/lock.h>
91 
92 #include <machine/clock.h>
93 #include <machine/ipl.h>
94 #ifndef SMP
95 #include <machine/lock.h>
96 #endif
97 #include <machine/resource.h>
98 
99 #include "sioreg.h"
100 #include "sio_private.h"
101 
102 #ifdef COM_ESP
103 #include "../ic_layer/esp.h"
104 #endif
105 
106 #define	LOTS_OF_EVENTS	64	/* helps separate urgent events from input */
107 
108 #define	CALLOUT_MASK		0x80
109 #define	CONTROL_MASK		0x60
110 #define	CONTROL_INIT_STATE	0x20
111 #define	CONTROL_LOCK_STATE	0x40
112 #define	DEV_TO_UNIT(dev)	(MINOR_TO_UNIT(minor(dev)))
113 #define	MINOR_TO_UNIT(mynor)	((((mynor) & ~0xffffU) >> (8 + 3)) \
114 				 | ((mynor) & 0x1f))
115 #define	UNIT_TO_MINOR(unit)	((((unit) & ~0x1fU) << (8 + 3)) \
116 				 | ((unit) & 0x1f))
117 
118 #define	com_scr		7	/* scratch register for 16450-16550 (R/W) */
119 
120 #define	sio_getreg(com, off) \
121 	(bus_space_read_1((com)->bst, (com)->bsh, (off)))
122 #define	sio_setreg(com, off, value) \
123 	(bus_space_write_1((com)->bst, (com)->bsh, (off), (value)))
124 
125 /*
126  * com state bits.
127  * (CS_BUSY | CS_TTGO) and (CS_BUSY | CS_TTGO | CS_ODEVREADY) must be higher
128  * than the other bits so that they can be tested as a group without masking
129  * off the low bits.
130  *
131  * The following com and tty flags correspond closely:
132  *	CS_BUSY		= TS_BUSY (maintained by comstart(), siopoll() and
133  *				   comstop())
134  *	CS_TTGO		= ~TS_TTSTOP (maintained by comparam() and comstart())
135  *	CS_CTS_OFLOW	= CCTS_OFLOW (maintained by comparam())
136  *	CS_RTS_IFLOW	= CRTS_IFLOW (maintained by comparam())
137  * TS_FLUSH is not used.
138  * XXX I think TIOCSETA doesn't clear TS_TTSTOP when it clears IXON.
139  * XXX CS_*FLOW should be CF_*FLOW in com->flags (control flags not state).
140  */
141 #define	CS_BUSY		0x80	/* output in progress */
142 #define	CS_TTGO		0x40	/* output not stopped by XOFF */
143 #define	CS_ODEVREADY	0x20	/* external device h/w ready (CTS) */
144 #define	CS_CHECKMSR	1	/* check of MSR scheduled */
145 #define	CS_CTS_OFLOW	2	/* use CTS output flow control */
146 #define	CS_DTR_OFF	0x10	/* DTR held off */
147 #define	CS_ODONE	4	/* output completed */
148 #define	CS_RTS_IFLOW	8	/* use RTS input flow control */
149 #define	CSE_BUSYCHECK	1	/* siobusycheck() scheduled */
150 
151 static	char const * const	error_desc[] = {
152 #define	CE_OVERRUN			0
153 	"silo overflow",
154 #define	CE_INTERRUPT_BUF_OVERFLOW	1
155 	"interrupt-level buffer overflow",
156 #define	CE_TTY_BUF_OVERFLOW		2
157 	"tty-level buffer overflow",
158 };
159 
160 #ifdef COM_ESP
161 static	int	espattach	(struct com_s *com, Port_t esp_port);
162 #endif
163 static	int	sio_isa_attach	(device_t dev);
164 
165 static	timeout_t siobusycheck;
166 static	u_int	siodivisor	(u_long rclk, speed_t speed);
167 static	timeout_t siodtrwakeup;
168 static	void	comhardclose	(struct com_s *com);
169 static	void	sioinput	(struct com_s *com);
170 static	void	siointr1	(struct com_s *com);
171 static	void	siointr		(void *arg);
172 static	int	commctl		(struct com_s *com, int bits, int how);
173 static	int	comparam	(struct tty *tp, struct termios *t);
174 static	inthand2_t siopoll;
175 static	int	sio_isa_probe	(device_t dev);
176 static	void	siosettimeout	(void);
177 static	int	siosetwater	(struct com_s *com, speed_t speed);
178 static	void	comstart	(struct tty *tp);
179 static	void	comstop		(struct tty *tp, int rw);
180 static	timeout_t comwakeup;
181 static	void	disc_optim	(struct tty	*tp, struct termios *t,
182 				     struct com_s *com);
183 
184 #if NPCI > 0
185 static	int	sio_pci_attach (device_t dev);
186 static	void	sio_pci_kludge_unit (device_t dev);
187 static	int	sio_pci_probe (device_t dev);
188 #endif /* NPCI > 0 */
189 
190 #if NPUC > 0
191 static	int	sio_puc_attach (device_t dev);
192 static	int	sio_puc_probe (device_t dev);
193 #endif /* NPUC > 0 */
194 
195 static char driver_name[] = "sio";
196 
197 /* table and macro for fast conversion from a unit number to its com struct */
198 devclass_t	sio_devclass;
199 #define	com_addr(unit)	((struct com_s *) \
200 			 devclass_get_softc(sio_devclass, unit))
201 
202 static device_method_t sio_isa_methods[] = {
203 	/* Device interface */
204 	DEVMETHOD(device_probe,		sio_isa_probe),
205 	DEVMETHOD(device_attach,	sio_isa_attach),
206 
207 	{ 0, 0 }
208 };
209 
210 static driver_t sio_isa_driver = {
211 	driver_name,
212 	sio_isa_methods,
213 	sizeof(struct com_s),
214 };
215 
216 #if NPCI > 0
217 static device_method_t sio_pci_methods[] = {
218 	/* Device interface */
219 	DEVMETHOD(device_probe,		sio_pci_probe),
220 	DEVMETHOD(device_attach,	sio_pci_attach),
221 
222 	{ 0, 0 }
223 };
224 
225 static driver_t sio_pci_driver = {
226 	driver_name,
227 	sio_pci_methods,
228 	sizeof(struct com_s),
229 };
230 #endif /* NPCI > 0 */
231 
232 #if NPUC > 0
233 static device_method_t sio_puc_methods[] = {
234 	/* Device interface */
235 	DEVMETHOD(device_probe,		sio_puc_probe),
236 	DEVMETHOD(device_attach,	sio_puc_attach),
237 
238 	{ 0, 0 }
239 };
240 
241 static driver_t sio_puc_driver = {
242 	driver_name,
243 	sio_puc_methods,
244 	sizeof(struct com_s),
245 };
246 #endif /* NPUC > 0 */
247 
248 static	d_open_t	sioopen;
249 static	d_close_t	sioclose;
250 static	d_read_t	sioread;
251 static	d_write_t	siowrite;
252 static	d_ioctl_t	sioioctl;
253 
254 #define	CDEV_MAJOR	28
255 static struct cdevsw sio_cdevsw = {
256 	/* name */	driver_name,
257 	/* maj */	CDEV_MAJOR,
258 	/* flags */	D_TTY | D_KQFILTER,
259 	/* port */	NULL,
260 	/* clone */	NULL,
261 
262 	/* open */	sioopen,
263 	/* close */	sioclose,
264 	/* read */	sioread,
265 	/* write */	siowrite,
266 	/* ioctl */	sioioctl,
267 	/* poll */	ttypoll,
268 	/* mmap */	nommap,
269 	/* strategy */	nostrategy,
270 	/* dump */	nodump,
271 	/* psize */	nopsize,
272 	/* kqfilter */	ttykqfilter
273 };
274 
275 int	comconsole = -1;
276 static	volatile speed_t	comdefaultrate = CONSPEED;
277 static	u_long			comdefaultrclk = DEFAULT_RCLK;
278 SYSCTL_ULONG(_machdep, OID_AUTO, conrclk, CTLFLAG_RW, &comdefaultrclk, 0, "");
279 static	u_int	com_events;	/* input chars + weighted output completions */
280 static	Port_t	siocniobase;
281 static	int	siocnunit;
282 static	Port_t	siogdbiobase;
283 static	int	siogdbunit = -1;
284 static	bool_t	sio_registered;
285 static	int	sio_timeout;
286 static	int	sio_timeouts_until_log;
287 static	struct	callout	sio_timeout_handle;
288 static	int	sio_numunits;
289 
290 #ifdef COM_ESP
291 /* XXX configure this properly. */
292 static	Port_t	likely_com_ports[] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8, };
293 static	Port_t	likely_esp_ports[] = { 0x140, 0x180, 0x280, 0 };
294 #endif
295 
296 /*
297  * handle sysctl read/write requests for console speed
298  *
299  * In addition to setting comdefaultrate for I/O through /dev/console,
300  * also set the initial and lock values for the /dev/ttyXX device
301  * if there is one associated with the console.  Finally, if the /dev/tty
302  * device has already been open, change the speed on the open running port
303  * itself.
304  */
305 
306 static int
307 sysctl_machdep_comdefaultrate(SYSCTL_HANDLER_ARGS)
308 {
309 	int error;
310 	speed_t newspeed;
311 	struct com_s *com;
312 	struct tty *tp;
313 
314 	newspeed = comdefaultrate;
315 
316 	error = sysctl_handle_opaque(oidp, &newspeed, sizeof newspeed, req);
317 	if (error || !req->newptr)
318 		return (error);
319 
320 	comdefaultrate = newspeed;
321 
322 	if (comconsole < 0)		/* serial console not selected? */
323 		return (0);
324 
325 	com = com_addr(comconsole);
326 	if (com == NULL)
327 		return (ENXIO);
328 
329 	/*
330 	 * set the initial and lock rates for /dev/ttydXX and /dev/cuaXX
331 	 * (note, the lock rates really are boolean -- if non-zero, disallow
332 	 *  speed changes)
333 	 */
334 	com->it_in.c_ispeed  = com->it_in.c_ospeed =
335 	com->lt_in.c_ispeed  = com->lt_in.c_ospeed =
336 	com->it_out.c_ispeed = com->it_out.c_ospeed =
337 	com->lt_out.c_ispeed = com->lt_out.c_ospeed = comdefaultrate;
338 
339 	/*
340 	 * if we're open, change the running rate too
341 	 */
342 	tp = com->tp;
343 	if (tp && (tp->t_state & TS_ISOPEN)) {
344 		tp->t_termios.c_ispeed =
345 		tp->t_termios.c_ospeed = comdefaultrate;
346 		crit_enter();
347 		error = comparam(tp, &tp->t_termios);
348 		crit_exit();
349 	}
350 	return error;
351 }
352 
353 SYSCTL_PROC(_machdep, OID_AUTO, conspeed, CTLTYPE_INT | CTLFLAG_RW,
354 	    0, 0, sysctl_machdep_comdefaultrate, "I", "");
355 
356 #if NPCI > 0
357 struct pci_ids {
358 	u_int32_t	type;
359 	const char	*desc;
360 	int		rid;
361 };
362 
363 static struct pci_ids pci_ids[] = {
364 	{ 0x100812b9, "3COM PCI FaxModem", 0x10 },
365 	{ 0x2000131f, "CyberSerial (1-port) 16550", 0x10 },
366 	{ 0x01101407, "Koutech IOFLEX-2S PCI Dual Port Serial", 0x10 },
367 	{ 0x01111407, "Koutech IOFLEX-2S PCI Dual Port Serial", 0x10 },
368 	{ 0x048011c1, "Lucent kermit based PCI Modem", 0x14 },
369 	{ 0x95211415, "Oxford Semiconductor PCI Dual Port Serial", 0x10 },
370 	{ 0x7101135e, "SeaLevel Ultra 530.PCI Single Port Serial", 0x18 },
371 	{ 0x0000151f, "SmartLink 5634PCV SurfRider", 0x10 },
372 	{ 0x98459710, "Netmos Nm9845 PCI Bridge with Dual UART", 0x10 },
373 	{ 0x00000000, NULL, 0 }
374 };
375 
376 static int
377 sio_pci_attach(dev)
378 	device_t	dev;
379 {
380 	u_int32_t	type;
381 	struct pci_ids	*id;
382 
383 	type = pci_get_devid(dev);
384 	id = pci_ids;
385 	while (id->type && id->type != type)
386 		id++;
387 	if (id->desc == NULL)
388 		return (ENXIO);
389 	sio_pci_kludge_unit(dev);
390 	return (sioattach(dev, id->rid, 0UL));
391 }
392 
393 /*
394  * Don't cut and paste this to other drivers.  It is a horrible kludge
395  * which will fail to work and also be unnecessary in future versions.
396  */
397 static void
398 sio_pci_kludge_unit(dev)
399 	device_t dev;
400 {
401 	devclass_t	dc;
402 	int		err;
403 	int		start;
404 	int		unit;
405 
406 	unit = 0;
407 	start = 0;
408 	while (resource_int_value("sio", unit, "port", &start) == 0 &&
409 	    start > 0)
410 		unit++;
411 	if (device_get_unit(dev) < unit) {
412 		dc = device_get_devclass(dev);
413 		while (devclass_get_device(dc, unit))
414 			unit++;
415 		device_printf(dev, "moving to sio%d\n", unit);
416 		err = device_set_unit(dev, unit);	/* EVIL DO NOT COPY */
417 		if (err)
418 			device_printf(dev, "error moving device %d\n", err);
419 	}
420 }
421 
422 static int
423 sio_pci_probe(dev)
424 	device_t	dev;
425 {
426 	u_int32_t	type;
427 	struct pci_ids	*id;
428 
429 	type = pci_get_devid(dev);
430 	id = pci_ids;
431 	while (id->type && id->type != type)
432 		id++;
433 	if (id->desc == NULL)
434 		return (ENXIO);
435 	device_set_desc(dev, id->desc);
436 	return (sioprobe(dev, id->rid, 0UL));
437 }
438 #endif /* NPCI > 0 */
439 
440 #if NPUC > 0
441 static int
442 sio_puc_attach(dev)
443 	device_t	dev;
444 {
445 	u_int rclk;
446 
447 	if (BUS_READ_IVAR(device_get_parent(dev), dev, PUC_IVAR_FREQ,
448 	    &rclk) != 0)
449 		rclk = DEFAULT_RCLK;
450 	return (sioattach(dev, 0, rclk));
451 }
452 
453 static int
454 sio_puc_probe(dev)
455 	device_t	dev;
456 {
457 	u_int rclk;
458 
459 	if (BUS_READ_IVAR(device_get_parent(dev), dev, PUC_IVAR_FREQ,
460 	    &rclk) != 0)
461 		rclk = DEFAULT_RCLK;
462 	return (sioprobe(dev, 0, rclk));
463 }
464 #endif /* NPUC */
465 
466 static struct isa_pnp_id sio_ids[] = {
467 	{0x0005d041, "Standard PC COM port"},	/* PNP0500 */
468 	{0x0105d041, "16550A-compatible COM port"},	/* PNP0501 */
469 	{0x0205d041, "Multiport serial device (non-intelligent 16550)"}, /* PNP0502 */
470 	{0x1005d041, "Generic IRDA-compatible device"},	/* PNP0510 */
471 	{0x1105d041, "Generic IRDA-compatible device"},	/* PNP0511 */
472 	/* Devices that do not have a compatid */
473 	{0x12206804, NULL},     /* ACH2012 - 5634BTS 56K Video Ready Modem */
474 	{0x7602a904, NULL},	/* AEI0276 - 56K v.90 Fax Modem (LKT) */
475 	{0x00007905, NULL},	/* AKY0000 - 56K Plug&Play Modem */
476 	{0x21107905, NULL},	/* AKY1021 - 56K Plug&Play Modem */
477 	{0x01405407, NULL},	/* AZT4001 - AZT3000 PnP SOUND DEVICE, MODEM */
478 	{0x56039008, NULL},	/* BDP0356 - Best Data 56x2 */
479 	{0x56159008, NULL},	/* BDP1556 - B.D. Smart One 56SPS,Voice Modem*/
480 	{0x36339008, NULL},	/* BDP3336 - Best Data Prods. 336F */
481 	{0x0014490a, NULL},	/* BRI1400 - Boca 33.6 PnP */
482 	{0x0015490a, NULL},	/* BRI1500 - Internal Fax Data */
483 	{0x0034490a, NULL},	/* BRI3400 - Internal ACF Modem */
484 	{0x0094490a, NULL},	/* BRI9400 - Boca K56Flex PnP */
485 	{0x00b4490a, NULL},	/* BRIB400 - Boca 56k PnP */
486 	{0x0030320d, NULL},	/* CIR3000 - Cirrus Logic V43 */
487 	{0x0100440e, NULL},	/* CRD0001 - Cardinal MVP288IV ? */
488 	{0x01308c0e, NULL},	/* CTL3001 - Creative Labs Phoneblaster */
489 	{0x36033610, NULL},     /* DAV0336 - DAVICOM 336PNP MODEM */
490 	{0x01009416, NULL},     /* ETT0001 - E-Tech Bullet 33k6 PnP */
491 	{0x0000aa1a, NULL},	/* FUJ0000 - FUJITSU Modem 33600 PNP/I2 */
492 	{0x1200c31e, NULL},	/* GVC0012 - VF1128HV-R9 (win modem?) */
493 	{0x0303c31e, NULL},	/* GVC0303 - MaxTech 33.6 PnP D/F/V */
494 	{0x0505c31e, NULL},	/* GVC0505 - GVC 56k Faxmodem */
495 	{0x0116c31e, NULL},	/* GVC1601 - Rockwell V.34 Plug & Play Modem */
496 	{0x0050c31e, NULL},	/* GVC5000 - some GVC modem */
497 	{0x3800f91e, NULL},	/* GWY0038 - Telepath with v.90 */
498 	{0x9062f91e, NULL},	/* GWY6290 - Telepath with x2 Technology */
499 	{0x8100e425, NULL},	/* IOD0081 - I-O DATA DEVICE,INC. IFML-560 */
500 	{0x21002534, NULL},	/* MAE0021 - Jetstream Int V.90 56k Voice Series 2*/
501 	{0x0000f435, NULL},	/* MOT0000 - Motorola ModemSURFR 33.6 Intern */
502 	{0x5015f435, NULL},	/* MOT1550 - Motorola ModemSURFR 56K Modem */
503 	{0xf015f435, NULL},	/* MOT15F0 - Motorola VoiceSURFR 56K Modem */
504 	{0x6045f435, NULL},	/* MOT4560 - Motorola ? */
505 	{0x61e7a338, NULL},	/* NECE761 - 33.6Modem */
506  	{0x08804f3f, NULL},	/* OZO8008 - Zoom  (33.6k Modem) */
507 	{0x0f804f3f, NULL},	/* OZO800f - Zoom 2812 (56k Modem) */
508 	{0x39804f3f, NULL},	/* OZO8039 - Zoom 56k flex */
509 	{0x00914f3f, NULL},	/* OZO9100 - Zoom 2919 (K56 Faxmodem) */
510 	{0x3024a341, NULL},	/* PMC2430 - Pace 56 Voice Internal Modem */
511 	{0x1000eb49, NULL},	/* ROK0010 - Rockwell ? */
512 	{0x1200b23d, NULL},     /* RSS0012 - OMRON ME5614ISA */
513 	{0x5002734a, NULL},	/* RSS0250 - 5614Jx3(G) Internal Modem */
514 	{0x6202734a, NULL},	/* RSS0262 - 5614Jx3[G] V90+K56Flex Modem */
515 	{0x1010104d, NULL},	/* SHP1010 - Rockwell 33600bps Modem */
516 	{0xc100ad4d, NULL},	/* SMM00C1 - Leopard 56k PnP */
517 	{0x9012b04e, NULL},	/* SUP1290 - Supra ? */
518 	{0x1013b04e, NULL},	/* SUP1310 - SupraExpress 336i PnP */
519 	{0x8013b04e, NULL},	/* SUP1380 - SupraExpress 288i PnP Voice */
520 	{0x8113b04e, NULL},	/* SUP1381 - SupraExpress 336i PnP Voice */
521 	{0x5016b04e, NULL},	/* SUP1650 - Supra 336i Sp Intl */
522 	{0x7016b04e, NULL},	/* SUP1670 - Supra 336i V+ Intl */
523 	{0x7420b04e, NULL},	/* SUP2070 - Supra ? */
524 	{0x8020b04e, NULL},	/* SUP2080 - Supra ? */
525 	{0x8420b04e, NULL},	/* SUP2084 - SupraExpress 56i PnP */
526 	{0x7121b04e, NULL},	/* SUP2171 - SupraExpress 56i Sp? */
527 	{0x8024b04e, NULL},	/* SUP2480 - Supra ? */
528 	{0x01007256, NULL},	/* USR0001 - U.S. Robotics Inc., Sportster W */
529 	{0x02007256, NULL},	/* USR0002 - U.S. Robotics Inc. Sportster 33. */
530 	{0x04007256, NULL},	/* USR0004 - USR Sportster 14.4k */
531 	{0x06007256, NULL},	/* USR0006 - USR Sportster 33.6k */
532 	{0x11007256, NULL},	/* USR0011 - USR ? */
533 	{0x01017256, NULL},	/* USR0101 - USR ? */
534 	{0x30207256, NULL},	/* USR2030 - U.S.Robotics Inc. Sportster 560 */
535 	{0x50207256, NULL},	/* USR2050 - U.S.Robotics Inc. Sportster 33. */
536 	{0x70207256, NULL},	/* USR2070 - U.S.Robotics Inc. Sportster 560 */
537 	{0x30307256, NULL},	/* USR3030 - U.S. Robotics 56K FAX INT */
538 	{0x31307256, NULL},	/* USR3031 - U.S. Robotics 56K FAX INT */
539 	{0x50307256, NULL},	/* USR3050 - U.S. Robotics 56K FAX INT */
540 	{0x70307256, NULL},	/* USR3070 - U.S. Robotics 56K Voice INT */
541 	{0x90307256, NULL},	/* USR3090 - USR ? */
542 	{0x70917256, NULL},	/* USR9170 - U.S. Robotics 56K FAX INT */
543 	{0x90917256, NULL},	/* USR9190 - USR 56k Voice INT */
544 	{0x0300695c, NULL},	/* WCI0003 - Fax/Voice/Modem/Speakphone/Asvd */
545 	{0x01a0896a, NULL},	/* ZTIA001 - Zoom Internal V90 Faxmodem */
546 	{0x61f7896a, NULL},	/* ZTIF761 - Zoom ComStar 33.6 */
547 	{0}
548 };
549 
550 
551 
552 static int
553 sio_isa_probe(dev)
554 	device_t	dev;
555 {
556 	/* Check isapnp ids */
557 	if (ISA_PNP_PROBE(device_get_parent(dev), dev, sio_ids) == ENXIO)
558 		return (ENXIO);
559 	return (sioprobe(dev, 0, 0UL));
560 }
561 
562 int
563 sioprobe(dev, xrid, rclk)
564 	device_t	dev;
565 	int		xrid;
566 	u_long		rclk;
567 {
568 #if 0
569 	static bool_t	already_init;
570 	device_t	xdev;
571 #endif
572 	struct com_s	*com;
573 	u_int		divisor;
574 	bool_t		failures[10];
575 	int		fn;
576 	device_t	idev;
577 	Port_t		iobase;
578 	intrmask_t	irqmap[4];
579 	intrmask_t	irqs;
580 	u_char		mcr_image;
581 	int		result;
582 	u_long		xirq;
583 	u_int		flags = device_get_flags(dev);
584 	int		rid;
585 	struct resource *port;
586 
587 	rid = xrid;
588 	port = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid,
589 				  0, ~0, IO_COMSIZE, RF_ACTIVE);
590 	if (!port)
591 		return (ENXIO);
592 
593 	com = device_get_softc(dev);
594 	com->bst = rman_get_bustag(port);
595 	com->bsh = rman_get_bushandle(port);
596 	if (rclk == 0)
597 		rclk = DEFAULT_RCLK;
598 	com->rclk = rclk;
599 
600 #if 0
601 	/*
602 	 * XXX this is broken - when we are first called, there are no
603 	 * previously configured IO ports.  We could hard code
604 	 * 0x3f8, 0x2f8, 0x3e8, 0x2e8 etc but that's probably worse.
605 	 * This code has been doing nothing since the conversion since
606 	 * "count" is zero the first time around.
607 	 */
608 	if (!already_init) {
609 		/*
610 		 * Turn off MCR_IENABLE for all likely serial ports.  An unused
611 		 * port with its MCR_IENABLE gate open will inhibit interrupts
612 		 * from any used port that shares the interrupt vector.
613 		 * XXX the gate enable is elsewhere for some multiports.
614 		 */
615 		device_t *devs;
616 		int count, i, xioport;
617 
618 		devclass_get_devices(sio_devclass, &devs, &count);
619 		for (i = 0; i < count; i++) {
620 			xdev = devs[i];
621 			if (device_is_enabled(xdev) &&
622 			    bus_get_resource(xdev, SYS_RES_IOPORT, 0, &xioport,
623 					     NULL) == 0)
624 				outb(xioport + com_mcr, 0);
625 		}
626 		free(devs, M_TEMP);
627 		already_init = TRUE;
628 	}
629 #endif
630 
631 	if (COM_LLCONSOLE(flags)) {
632 		printf("sio%d: reserved for low-level i/o\n",
633 		       device_get_unit(dev));
634 		bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
635 		return (ENXIO);
636 	}
637 
638 	/*
639 	 * If the device is on a multiport card and has an AST/4
640 	 * compatible interrupt control register, initialize this
641 	 * register and prepare to leave MCR_IENABLE clear in the mcr.
642 	 * Otherwise, prepare to set MCR_IENABLE in the mcr.
643 	 * Point idev to the device struct giving the correct id_irq.
644 	 * This is the struct for the master device if there is one.
645 	 */
646 	idev = dev;
647 	mcr_image = MCR_IENABLE;
648 #ifdef COM_MULTIPORT
649 	if (COM_ISMULTIPORT(flags)) {
650 		Port_t xiobase;
651 		u_long io;
652 
653 		idev = devclass_get_device(sio_devclass, COM_MPMASTER(flags));
654 		if (idev == NULL) {
655 			printf("sio%d: master device %d not configured\n",
656 			       device_get_unit(dev), COM_MPMASTER(flags));
657 			idev = dev;
658 		}
659 		if (!COM_NOTAST4(flags)) {
660 			if (bus_get_resource(idev, SYS_RES_IOPORT, 0, &io,
661 					     NULL) == 0) {
662 				xiobase = io;
663 				if (bus_get_resource(idev, SYS_RES_IRQ, 0,
664 				    NULL, NULL) == 0)
665 					outb(xiobase + com_scr, 0x80);
666 				else
667 					outb(xiobase + com_scr, 0);
668 			}
669 			mcr_image = 0;
670 		}
671 	}
672 #endif /* COM_MULTIPORT */
673 	if (bus_get_resource(idev, SYS_RES_IRQ, 0, NULL, NULL) != 0)
674 		mcr_image = 0;
675 
676 	bzero(failures, sizeof failures);
677 	iobase = rman_get_start(port);
678 
679 	/*
680 	 * We don't want to get actual interrupts, just masked ones.
681 	 * Interrupts from this line should already be masked in the ICU,
682 	 * but mask them in the processor as well in case there are some
683 	 * (misconfigured) shared interrupts.
684 	 */
685 	com_lock();
686 /* EXTRA DELAY? */
687 
688 	/*
689 	 * For the TI16754 chips, set prescaler to 1 (4 is often the
690 	 * default after-reset value) as otherwise it's impossible to
691 	 * get highest baudrates.
692 	 */
693 	if (COM_TI16754(flags)) {
694 		u_char cfcr, efr;
695 
696 		cfcr = sio_getreg(com, com_cfcr);
697 		sio_setreg(com, com_cfcr, CFCR_EFR_ENABLE);
698 		efr = sio_getreg(com, com_efr);
699 		/* Unlock extended features to turn off prescaler. */
700 		sio_setreg(com, com_efr, efr | EFR_EFE);
701 		/* Disable EFR. */
702 		sio_setreg(com, com_cfcr, (cfcr != CFCR_EFR_ENABLE) ? cfcr : 0);
703 		/* Turn off prescaler. */
704 		sio_setreg(com, com_mcr,
705 			   sio_getreg(com, com_mcr) & ~MCR_PRESCALE);
706 		sio_setreg(com, com_cfcr, CFCR_EFR_ENABLE);
707 		sio_setreg(com, com_efr, efr);
708 		sio_setreg(com, com_cfcr, cfcr);
709 	}
710 
711 	/*
712 	 * Initialize the speed and the word size and wait long enough to
713 	 * drain the maximum of 16 bytes of junk in device output queues.
714 	 * The speed is undefined after a master reset and must be set
715 	 * before relying on anything related to output.  There may be
716 	 * junk after a (very fast) soft reboot and (apparently) after
717 	 * master reset.
718 	 * XXX what about the UART bug avoided by waiting in comparam()?
719 	 * We don't want to to wait long enough to drain at 2 bps.
720 	 */
721 	if (iobase == siocniobase) {
722 		DELAY((16 + 1) * 1000000 / (comdefaultrate / 10));
723 	} else {
724 		sio_setreg(com, com_cfcr, CFCR_DLAB | CFCR_8BITS);
725 		divisor = siodivisor(rclk, SIO_TEST_SPEED);
726 		sio_setreg(com, com_dlbl, divisor & 0xff);
727 		sio_setreg(com, com_dlbh, divisor >> 8);
728 		sio_setreg(com, com_cfcr, CFCR_8BITS);
729 		DELAY((16 + 1) * 1000000 / (SIO_TEST_SPEED / 10));
730 	}
731 
732 	/*
733 	 * Make sure we can drain the receiver.  If we can't, the serial
734 	 * port may not exist.
735 	 */
736 	for (fn = 0; fn < 256; ++fn) {
737 		if ((sio_getreg(com, com_lsr) & LSR_RXRDY) == 0)
738 			break;
739 		(void)sio_getreg(com, com_data);
740 	}
741 	if (fn == 256) {
742 		printf("sio%d: can't drain, serial port might "
743 			"not exist, disabling\n", device_get_unit(dev));
744 		com_unlock();
745 		return (ENXIO);
746 	}
747 
748 	/*
749 	 * Enable the interrupt gate and disable device interupts.  This
750 	 * should leave the device driving the interrupt line low and
751 	 * guarantee an edge trigger if an interrupt can be generated.
752 	 */
753 /* EXTRA DELAY? */
754 	sio_setreg(com, com_mcr, mcr_image);
755 	sio_setreg(com, com_ier, 0);
756 	DELAY(1000);		/* XXX */
757 	irqmap[0] = isa_irq_pending();
758 
759 	/*
760 	 * Attempt to set loopback mode so that we can send a null byte
761 	 * without annoying any external device.
762 	 */
763 /* EXTRA DELAY? */
764 	sio_setreg(com, com_mcr, mcr_image | MCR_LOOPBACK);
765 
766 	/*
767 	 * Attempt to generate an output interrupt.  On 8250's, setting
768 	 * IER_ETXRDY generates an interrupt independent of the current
769 	 * setting and independent of whether the THR is empty.  On 16450's,
770 	 * setting IER_ETXRDY generates an interrupt independent of the
771 	 * current setting.  On 16550A's, setting IER_ETXRDY only
772 	 * generates an interrupt when IER_ETXRDY is not already set.
773 	 */
774 	sio_setreg(com, com_ier, IER_ETXRDY);
775 
776 	/*
777 	 * On some 16x50 incompatibles, setting IER_ETXRDY doesn't generate
778 	 * an interrupt.  They'd better generate one for actually doing
779 	 * output.  Loopback may be broken on the same incompatibles but
780 	 * it's unlikely to do more than allow the null byte out.
781 	 */
782 	sio_setreg(com, com_data, 0);
783 	DELAY((1 + 2) * 1000000 / (SIO_TEST_SPEED / 10));
784 
785 	/*
786 	 * Turn off loopback mode so that the interrupt gate works again
787 	 * (MCR_IENABLE was hidden).  This should leave the device driving
788 	 * an interrupt line high.  It doesn't matter if the interrupt
789 	 * line oscillates while we are not looking at it, since interrupts
790 	 * are disabled.
791 	 */
792 /* EXTRA DELAY? */
793 	sio_setreg(com, com_mcr, mcr_image);
794 
795 	/*
796 	 * Some pcmcia cards have the "TXRDY bug", so we check everyone
797 	 * for IIR_TXRDY implementation ( Palido 321s, DC-1S... )
798 	 */
799 	if (COM_NOPROBE(flags)) {
800 		/* Reading IIR register twice */
801 		for (fn = 0; fn < 2; fn ++) {
802 			DELAY(10000);
803 			failures[6] = sio_getreg(com, com_iir);
804 		}
805 		/* Check IIR_TXRDY clear ? */
806 		result = 0;
807 		if (failures[6] & IIR_TXRDY) {
808 			/* Nop, Double check with clearing IER */
809 			sio_setreg(com, com_ier, 0);
810 			if (sio_getreg(com, com_iir) & IIR_NOPEND) {
811 				/* Ok. we're familia this gang */
812 				SET_FLAG(dev, COM_C_IIR_TXRDYBUG);
813 			} else {
814 				/* Unknown, Just omit this chip.. XXX */
815 				result = ENXIO;
816 				sio_setreg(com, com_mcr, 0);
817 			}
818 		} else {
819 			/* OK. this is well-known guys */
820 			CLR_FLAG(dev, COM_C_IIR_TXRDYBUG);
821 		}
822 		sio_setreg(com, com_ier, 0);
823 		sio_setreg(com, com_cfcr, CFCR_8BITS);
824 		com_unlock();
825 		bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
826 		return (iobase == siocniobase ? 0 : result);
827 	}
828 
829 	/*
830 	 * Check that
831 	 *	o the CFCR, IER and MCR in UART hold the values written to them
832 	 *	  (the values happen to be all distinct - this is good for
833 	 *	  avoiding false positive tests from bus echoes).
834 	 *	o an output interrupt is generated and its vector is correct.
835 	 *	o the interrupt goes away when the IIR in the UART is read.
836 	 */
837 /* EXTRA DELAY? */
838 	failures[0] = sio_getreg(com, com_cfcr) - CFCR_8BITS;
839 	failures[1] = sio_getreg(com, com_ier) - IER_ETXRDY;
840 	failures[2] = sio_getreg(com, com_mcr) - mcr_image;
841 	DELAY(10000);		/* Some internal modems need this time */
842 	irqmap[1] = isa_irq_pending();
843 	failures[4] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_TXRDY;
844 	DELAY(1000);		/* XXX */
845 	irqmap[2] = isa_irq_pending();
846 	failures[6] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_NOPEND;
847 
848 	/*
849 	 * Turn off all device interrupts and check that they go off properly.
850 	 * Leave MCR_IENABLE alone.  For ports without a master port, it gates
851 	 * the OUT2 output of the UART to
852 	 * the ICU input.  Closing the gate would give a floating ICU input
853 	 * (unless there is another device driving it) and spurious interrupts.
854 	 * (On the system that this was first tested on, the input floats high
855 	 * and gives a (masked) interrupt as soon as the gate is closed.)
856 	 */
857 	sio_setreg(com, com_ier, 0);
858 	sio_setreg(com, com_cfcr, CFCR_8BITS);	/* dummy to avoid bus echo */
859 	failures[7] = sio_getreg(com, com_ier);
860 	DELAY(1000);		/* XXX */
861 	irqmap[3] = isa_irq_pending();
862 	failures[9] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_NOPEND;
863 
864 	com_unlock();
865 
866 	irqs = irqmap[1] & ~irqmap[0];
867 	if (bus_get_resource(idev, SYS_RES_IRQ, 0, &xirq, NULL) == 0 &&
868 	    ((1 << xirq) & irqs) == 0)
869 		printf(
870 		"sio%d: configured irq %ld not in bitmap of probed irqs %#x\n",
871 		    device_get_unit(dev), xirq, irqs);
872 	if (bootverbose)
873 		printf("sio%d: irq maps: %#x %#x %#x %#x\n",
874 		    device_get_unit(dev),
875 		    irqmap[0], irqmap[1], irqmap[2], irqmap[3]);
876 
877 	result = 0;
878 	for (fn = 0; fn < sizeof failures; ++fn)
879 		if (failures[fn]) {
880 			sio_setreg(com, com_mcr, 0);
881 			result = ENXIO;
882 			if (bootverbose) {
883 				printf("sio%d: probe failed test(s):",
884 				    device_get_unit(dev));
885 				for (fn = 0; fn < sizeof failures; ++fn)
886 					if (failures[fn])
887 						printf(" %d", fn);
888 				printf("\n");
889 			}
890 			break;
891 		}
892 	bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
893 	return (iobase == siocniobase ? 0 : result);
894 }
895 
896 #ifdef COM_ESP
897 static int
898 espattach(com, esp_port)
899 	struct com_s		*com;
900 	Port_t			esp_port;
901 {
902 	u_char	dips;
903 	u_char	val;
904 
905 	/*
906 	 * Check the ESP-specific I/O port to see if we're an ESP
907 	 * card.  If not, return failure immediately.
908 	 */
909 	if ((inb(esp_port) & 0xf3) == 0) {
910 		printf(" port 0x%x is not an ESP board?\n", esp_port);
911 		return (0);
912 	}
913 
914 	/*
915 	 * We've got something that claims to be a Hayes ESP card.
916 	 * Let's hope so.
917 	 */
918 
919 	/* Get the dip-switch configuration */
920 	outb(esp_port + ESP_CMD1, ESP_GETDIPS);
921 	dips = inb(esp_port + ESP_STATUS1);
922 
923 	/*
924 	 * Bits 0,1 of dips say which COM port we are.
925 	 */
926 	if (rman_get_start(com->ioportres) == likely_com_ports[dips & 0x03])
927 		printf(" : ESP");
928 	else {
929 		printf(" esp_port has com %d\n", dips & 0x03);
930 		return (0);
931 	}
932 
933 	/*
934 	 * Check for ESP version 2.0 or later:  bits 4,5,6 = 010.
935 	 */
936 	outb(esp_port + ESP_CMD1, ESP_GETTEST);
937 	val = inb(esp_port + ESP_STATUS1);	/* clear reg 1 */
938 	val = inb(esp_port + ESP_STATUS2);
939 	if ((val & 0x70) < 0x20) {
940 		printf("-old (%o)", val & 0x70);
941 		return (0);
942 	}
943 
944 	/*
945 	 * Check for ability to emulate 16550:  bit 7 == 1
946 	 */
947 	if ((dips & 0x80) == 0) {
948 		printf(" slave");
949 		return (0);
950 	}
951 
952 	/*
953 	 * Okay, we seem to be a Hayes ESP card.  Whee.
954 	 */
955 	com->esp = TRUE;
956 	com->esp_port = esp_port;
957 	return (1);
958 }
959 #endif /* COM_ESP */
960 
961 static int
962 sio_isa_attach(dev)
963 	device_t	dev;
964 {
965 	return (sioattach(dev, 0, 0UL));
966 }
967 
968 int
969 sioattach(dev, xrid, rclk)
970 	device_t	dev;
971 	int		xrid;
972 	u_long		rclk;
973 {
974 	struct com_s	*com;
975 #ifdef COM_ESP
976 	Port_t		*espp;
977 #endif
978 	Port_t		iobase;
979 	int		minorbase;
980 	int		unit;
981 	u_int		flags;
982 	int		rid;
983 	struct resource *port;
984 	int		ret;
985 	static int	did_init;
986 
987 	if (did_init == 0) {
988 		did_init = 1;
989 		callout_init(&sio_timeout_handle);
990 	}
991 
992 	rid = xrid;
993 	port = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid,
994 				  0, ~0, IO_COMSIZE, RF_ACTIVE);
995 	if (!port)
996 		return (ENXIO);
997 
998 	iobase = rman_get_start(port);
999 	unit = device_get_unit(dev);
1000 	com = device_get_softc(dev);
1001 	flags = device_get_flags(dev);
1002 
1003 	if (unit >= sio_numunits)
1004 		sio_numunits = unit + 1;
1005 	/*
1006 	 * sioprobe() has initialized the device registers as follows:
1007 	 *	o cfcr = CFCR_8BITS.
1008 	 *	  It is most important that CFCR_DLAB is off, so that the
1009 	 *	  data port is not hidden when we enable interrupts.
1010 	 *	o ier = 0.
1011 	 *	  Interrupts are only enabled when the line is open.
1012 	 *	o mcr = MCR_IENABLE, or 0 if the port has AST/4 compatible
1013 	 *	  interrupt control register or the config specifies no irq.
1014 	 *	  Keeping MCR_DTR and MCR_RTS off might stop the external
1015 	 *	  device from sending before we are ready.
1016 	 */
1017 	bzero(com, sizeof *com);
1018 	com->unit = unit;
1019 	com->ioportres = port;
1020 	com->bst = rman_get_bustag(port);
1021 	com->bsh = rman_get_bushandle(port);
1022 	com->cfcr_image = CFCR_8BITS;
1023 	com->dtr_wait = 3 * hz;
1024 	callout_init(&com->dtr_ch);
1025 	callout_init(&com->busy_ch);
1026 	com->loses_outints = COM_LOSESOUTINTS(flags) != 0;
1027 	com->no_irq = bus_get_resource(dev, SYS_RES_IRQ, 0, NULL, NULL) != 0;
1028 	com->tx_fifo_size = 1;
1029 	com->obufs[0].l_head = com->obuf1;
1030 	com->obufs[1].l_head = com->obuf2;
1031 
1032 	com->data_port = iobase + com_data;
1033 	com->int_id_port = iobase + com_iir;
1034 	com->modem_ctl_port = iobase + com_mcr;
1035 	com->mcr_image = inb(com->modem_ctl_port);
1036 	com->line_status_port = iobase + com_lsr;
1037 	com->modem_status_port = iobase + com_msr;
1038 	com->intr_ctl_port = iobase + com_ier;
1039 
1040 	if (rclk == 0)
1041 		rclk = DEFAULT_RCLK;
1042 	com->rclk = rclk;
1043 
1044 	/*
1045 	 * We don't use all the flags from <sys/ttydefaults.h> since they
1046 	 * are only relevant for logins.  It's important to have echo off
1047 	 * initially so that the line doesn't start blathering before the
1048 	 * echo flag can be turned off.
1049 	 */
1050 	com->it_in.c_iflag = 0;
1051 	com->it_in.c_oflag = 0;
1052 	com->it_in.c_cflag = TTYDEF_CFLAG;
1053 	com->it_in.c_lflag = 0;
1054 	if (unit == comconsole) {
1055 		com->it_in.c_iflag = TTYDEF_IFLAG;
1056 		com->it_in.c_oflag = TTYDEF_OFLAG;
1057 		com->it_in.c_cflag = TTYDEF_CFLAG | CLOCAL;
1058 		com->it_in.c_lflag = TTYDEF_LFLAG;
1059 		com->lt_out.c_cflag = com->lt_in.c_cflag = CLOCAL;
1060 		com->lt_out.c_ispeed = com->lt_out.c_ospeed =
1061 		com->lt_in.c_ispeed = com->lt_in.c_ospeed =
1062 		com->it_in.c_ispeed = com->it_in.c_ospeed = comdefaultrate;
1063 	} else
1064 		com->it_in.c_ispeed = com->it_in.c_ospeed = TTYDEF_SPEED;
1065 	if (siosetwater(com, com->it_in.c_ispeed) != 0) {
1066 		com_unlock();
1067 		/*
1068 		 * Leave i/o resources allocated if this is a `cn'-level
1069 		 * console, so that other devices can't snarf them.
1070 		 */
1071 		if (iobase != siocniobase)
1072 			bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
1073 		return (ENOMEM);
1074 	}
1075 	com_unlock();
1076 	termioschars(&com->it_in);
1077 	com->it_out = com->it_in;
1078 
1079 	/* attempt to determine UART type */
1080 	printf("sio%d: type", unit);
1081 
1082 
1083 #ifdef COM_MULTIPORT
1084 	if (!COM_ISMULTIPORT(flags) && !COM_IIR_TXRDYBUG(flags))
1085 #else
1086 	if (!COM_IIR_TXRDYBUG(flags))
1087 #endif
1088 	{
1089 		u_char	scr;
1090 		u_char	scr1;
1091 		u_char	scr2;
1092 
1093 		scr = sio_getreg(com, com_scr);
1094 		sio_setreg(com, com_scr, 0xa5);
1095 		scr1 = sio_getreg(com, com_scr);
1096 		sio_setreg(com, com_scr, 0x5a);
1097 		scr2 = sio_getreg(com, com_scr);
1098 		sio_setreg(com, com_scr, scr);
1099 		if (scr1 != 0xa5 || scr2 != 0x5a) {
1100 			printf(" 8250");
1101 			goto determined_type;
1102 		}
1103 	}
1104 	sio_setreg(com, com_fifo, FIFO_ENABLE | FIFO_RX_HIGH);
1105 	DELAY(100);
1106 	com->st16650a = 0;
1107 	switch (inb(com->int_id_port) & IIR_FIFO_MASK) {
1108 	case FIFO_RX_LOW:
1109 		printf(" 16450");
1110 		break;
1111 	case FIFO_RX_MEDL:
1112 		printf(" 16450?");
1113 		break;
1114 	case FIFO_RX_MEDH:
1115 		printf(" 16550?");
1116 		break;
1117 	case FIFO_RX_HIGH:
1118 		if (COM_NOFIFO(flags)) {
1119 			printf(" 16550A fifo disabled");
1120 		} else {
1121 			com->hasfifo = TRUE;
1122 			if (COM_ST16650A(flags)) {
1123 				com->st16650a = 1;
1124 				com->tx_fifo_size = 32;
1125 				printf(" ST16650A");
1126 			} else if (COM_TI16754(flags)) {
1127 				com->tx_fifo_size = 64;
1128 				printf(" TI16754");
1129 			} else {
1130 				com->tx_fifo_size = COM_FIFOSIZE(flags);
1131 				printf(" 16550A");
1132 			}
1133 		}
1134 #ifdef COM_ESP
1135 		for (espp = likely_esp_ports; *espp != 0; espp++)
1136 			if (espattach(com, *espp)) {
1137 				com->tx_fifo_size = 1024;
1138 				break;
1139 			}
1140 #endif
1141 		if (!com->st16650a && !COM_TI16754(flags)) {
1142 			if (!com->tx_fifo_size)
1143 				com->tx_fifo_size = 16;
1144 			else
1145 				printf(" lookalike with %d bytes FIFO",
1146 				    com->tx_fifo_size);
1147 		}
1148 
1149 		break;
1150 	}
1151 
1152 #ifdef COM_ESP
1153 	if (com->esp) {
1154 		/*
1155 		 * Set 16550 compatibility mode.
1156 		 * We don't use the ESP_MODE_SCALE bit to increase the
1157 		 * fifo trigger levels because we can't handle large
1158 		 * bursts of input.
1159 		 * XXX flow control should be set in comparam(), not here.
1160 		 */
1161 		outb(com->esp_port + ESP_CMD1, ESP_SETMODE);
1162 		outb(com->esp_port + ESP_CMD2, ESP_MODE_RTS | ESP_MODE_FIFO);
1163 
1164 		/* Set RTS/CTS flow control. */
1165 		outb(com->esp_port + ESP_CMD1, ESP_SETFLOWTYPE);
1166 		outb(com->esp_port + ESP_CMD2, ESP_FLOW_RTS);
1167 		outb(com->esp_port + ESP_CMD2, ESP_FLOW_CTS);
1168 
1169 		/* Set flow-control levels. */
1170 		outb(com->esp_port + ESP_CMD1, ESP_SETRXFLOW);
1171 		outb(com->esp_port + ESP_CMD2, HIBYTE(768));
1172 		outb(com->esp_port + ESP_CMD2, LOBYTE(768));
1173 		outb(com->esp_port + ESP_CMD2, HIBYTE(512));
1174 		outb(com->esp_port + ESP_CMD2, LOBYTE(512));
1175 	}
1176 #endif /* COM_ESP */
1177 	sio_setreg(com, com_fifo, 0);
1178 determined_type: ;
1179 
1180 #ifdef COM_MULTIPORT
1181 	if (COM_ISMULTIPORT(flags)) {
1182 		device_t masterdev;
1183 
1184 		com->multiport = TRUE;
1185 		printf(" (multiport");
1186 		if (unit == COM_MPMASTER(flags))
1187 			printf(" master");
1188 		printf(")");
1189 		masterdev = devclass_get_device(sio_devclass,
1190 		    COM_MPMASTER(flags));
1191 		com->no_irq = (masterdev == NULL || bus_get_resource(masterdev,
1192 		    SYS_RES_IRQ, 0, NULL, NULL) != 0);
1193 	 }
1194 #endif /* COM_MULTIPORT */
1195 	if (unit == comconsole)
1196 		printf(", console");
1197 	if (COM_IIR_TXRDYBUG(flags))
1198 		printf(" with a bogus IIR_TXRDY register");
1199 	printf("\n");
1200 
1201 	if (!sio_registered) {
1202 		register_swi(SWI_TTY, siopoll, NULL ,"swi_siopoll");
1203 		sio_registered = TRUE;
1204 	}
1205 	minorbase = UNIT_TO_MINOR(unit);
1206 	cdevsw_add(&sio_cdevsw, UNIT_TO_MINOR(-1), minorbase);
1207 	make_dev(&sio_cdevsw, minorbase,
1208 	    UID_ROOT, GID_WHEEL, 0600, "ttyd%r", unit);
1209 	make_dev(&sio_cdevsw, minorbase | CONTROL_INIT_STATE,
1210 	    UID_ROOT, GID_WHEEL, 0600, "ttyid%r", unit);
1211 	make_dev(&sio_cdevsw, minorbase | CONTROL_LOCK_STATE,
1212 	    UID_ROOT, GID_WHEEL, 0600, "ttyld%r", unit);
1213 	make_dev(&sio_cdevsw, minorbase | CALLOUT_MASK,
1214 	    UID_UUCP, GID_DIALER, 0660, "cuaa%r", unit);
1215 	make_dev(&sio_cdevsw, minorbase | CALLOUT_MASK | CONTROL_INIT_STATE,
1216 	    UID_UUCP, GID_DIALER, 0660, "cuaia%r", unit);
1217 	make_dev(&sio_cdevsw, minorbase | CALLOUT_MASK | CONTROL_LOCK_STATE,
1218 	    UID_UUCP, GID_DIALER, 0660, "cuala%r", unit);
1219 	com->flags = flags;
1220 	com->pps.ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR;
1221 	pps_init(&com->pps);
1222 
1223 	rid = 0;
1224 	com->irqres = bus_alloc_resource(dev, SYS_RES_IRQ, &rid, 0ul, ~0ul, 1,
1225 	    RF_ACTIVE);
1226 	if (com->irqres) {
1227 		ret = BUS_SETUP_INTR(device_get_parent(dev), dev, com->irqres,
1228 				     INTR_TYPE_TTY | INTR_FAST,
1229 				     siointr, com, &com->cookie, NULL);
1230 		if (ret) {
1231 			ret = BUS_SETUP_INTR(device_get_parent(dev), dev,
1232 					     com->irqres, INTR_TYPE_TTY,
1233 					     siointr, com, &com->cookie, NULL);
1234 			if (ret == 0)
1235 				device_printf(dev, "unable to activate interrupt in fast mode - using normal mode\n");
1236 		}
1237 		if (ret)
1238 			device_printf(dev, "could not activate interrupt\n");
1239 #if defined(DDB) && (defined(BREAK_TO_DEBUGGER) || \
1240     defined(ALT_BREAK_TO_DEBUGGER))
1241 		/*
1242 		 * Enable interrupts for early break-to-debugger support
1243 		 * on the console.
1244 		 */
1245 		if (ret == 0 && unit == comconsole)
1246 			outb(siocniobase + com_ier, IER_ERXRDY | IER_ERLS |
1247 			    IER_EMSC);
1248 #endif
1249 	}
1250 
1251 	return (0);
1252 }
1253 
1254 static int
1255 sioopen(dev_t dev, int flag, int mode, struct thread *td)
1256 {
1257 	struct com_s	*com;
1258 	int		error;
1259 	int		mynor;
1260 	struct tty	*tp;
1261 	int		unit;
1262 
1263 	mynor = minor(dev);
1264 	unit = MINOR_TO_UNIT(mynor);
1265 	com = com_addr(unit);
1266 	if (com == NULL)
1267 		return (ENXIO);
1268 	if (com->gone)
1269 		return (ENXIO);
1270 	if (mynor & CONTROL_MASK)
1271 		return (0);
1272 	tp = dev->si_tty = com->tp = ttymalloc(com->tp);
1273 	crit_enter();
1274 	/*
1275 	 * We jump to this label after all non-interrupted sleeps to pick
1276 	 * up any changes of the device state.
1277 	 */
1278 open_top:
1279 	while (com->state & CS_DTR_OFF) {
1280 		error = tsleep(&com->dtr_wait, PCATCH, "siodtr", 0);
1281 		if (com_addr(unit) == NULL)
1282 			return (ENXIO);
1283 		if (error != 0 || com->gone)
1284 			goto out;
1285 	}
1286 	if (tp->t_state & TS_ISOPEN) {
1287 		/*
1288 		 * The device is open, so everything has been initialized.
1289 		 * Handle conflicts.
1290 		 */
1291 		if (mynor & CALLOUT_MASK) {
1292 			if (!com->active_out) {
1293 				error = EBUSY;
1294 				goto out;
1295 			}
1296 		} else {
1297 			if (com->active_out) {
1298 				if (flag & O_NONBLOCK) {
1299 					error = EBUSY;
1300 					goto out;
1301 				}
1302 				error =	tsleep(&com->active_out,
1303 					       PCATCH, "siobi", 0);
1304 				if (com_addr(unit) == NULL)
1305 					return (ENXIO);
1306 				if (error != 0 || com->gone)
1307 					goto out;
1308 				goto open_top;
1309 			}
1310 		}
1311 		if (tp->t_state & TS_XCLUDE && suser(td)) {
1312 			error = EBUSY;
1313 			goto out;
1314 		}
1315 	} else {
1316 		/*
1317 		 * The device isn't open, so there are no conflicts.
1318 		 * Initialize it.  Initialization is done twice in many
1319 		 * cases: to preempt sleeping callin opens if we are
1320 		 * callout, and to complete a callin open after DCD rises.
1321 		 */
1322 		tp->t_oproc = comstart;
1323 		tp->t_param = comparam;
1324 		tp->t_stop = comstop;
1325 		tp->t_dev = dev;
1326 		tp->t_termios = mynor & CALLOUT_MASK
1327 				? com->it_out : com->it_in;
1328 		(void)commctl(com, TIOCM_DTR | TIOCM_RTS, DMSET);
1329 		com->poll = com->no_irq;
1330 		com->poll_output = com->loses_outints;
1331 		++com->wopeners;
1332 		error = comparam(tp, &tp->t_termios);
1333 		--com->wopeners;
1334 		if (error != 0)
1335 			goto out;
1336 		/*
1337 		 * XXX we should goto open_top if comparam() slept.
1338 		 */
1339 		if (com->hasfifo) {
1340 			/*
1341 			 * (Re)enable and drain fifos.
1342 			 *
1343 			 * Certain SMC chips cause problems if the fifos
1344 			 * are enabled while input is ready.  Turn off the
1345 			 * fifo if necessary to clear the input.  We test
1346 			 * the input ready bit after enabling the fifos
1347 			 * since we've already enabled them in comparam()
1348 			 * and to handle races between enabling and fresh
1349 			 * input.
1350 			 */
1351 			while (TRUE) {
1352 				sio_setreg(com, com_fifo,
1353 					   FIFO_RCV_RST | FIFO_XMT_RST
1354 					   | com->fifo_image);
1355 				/*
1356 				 * XXX the delays are for superstitious
1357 				 * historical reasons.  It must be less than
1358 				 * the character time at the maximum
1359 				 * supported speed (87 usec at 115200 bps
1360 				 * 8N1).  Otherwise we might loop endlessly
1361 				 * if data is streaming in.  We used to use
1362 				 * delays of 100.  That usually worked
1363 				 * because DELAY(100) used to usually delay
1364 				 * for about 85 usec instead of 100.
1365 				 */
1366 				DELAY(50);
1367 				if (!(inb(com->line_status_port) & LSR_RXRDY))
1368 					break;
1369 				sio_setreg(com, com_fifo, 0);
1370 				DELAY(50);
1371 				(void) inb(com->data_port);
1372 			}
1373 		}
1374 
1375 		com_lock();
1376 		(void) inb(com->line_status_port);
1377 		(void) inb(com->data_port);
1378 		com->prev_modem_status = com->last_modem_status
1379 		    = inb(com->modem_status_port);
1380 		if (COM_IIR_TXRDYBUG(com->flags)) {
1381 			outb(com->intr_ctl_port, IER_ERXRDY | IER_ERLS
1382 						| IER_EMSC);
1383 		} else {
1384 			outb(com->intr_ctl_port, IER_ERXRDY | IER_ETXRDY
1385 						| IER_ERLS | IER_EMSC);
1386 		}
1387 		com_unlock();
1388 		/*
1389 		 * Handle initial DCD.  Callout devices get a fake initial
1390 		 * DCD (trapdoor DCD).  If we are callout, then any sleeping
1391 		 * callin opens get woken up and resume sleeping on "siobi"
1392 		 * instead of "siodcd".
1393 		 */
1394 		/*
1395 		 * XXX `mynor & CALLOUT_MASK' should be
1396 		 * `tp->t_cflag & (SOFT_CARRIER | TRAPDOOR_CARRIER) where
1397 		 * TRAPDOOR_CARRIER is the default initial state for callout
1398 		 * devices and SOFT_CARRIER is like CLOCAL except it hides
1399 		 * the true carrier.
1400 		 */
1401 		if (com->prev_modem_status & MSR_DCD || mynor & CALLOUT_MASK)
1402 			(*linesw[tp->t_line].l_modem)(tp, 1);
1403 	}
1404 	/*
1405 	 * Wait for DCD if necessary.
1406 	 */
1407 	if (!(tp->t_state & TS_CARR_ON) && !(mynor & CALLOUT_MASK)
1408 	    && !(tp->t_cflag & CLOCAL) && !(flag & O_NONBLOCK)) {
1409 		++com->wopeners;
1410 		error = tsleep(TSA_CARR_ON(tp), PCATCH, "siodcd", 0);
1411 		if (com_addr(unit) == NULL)
1412 			return (ENXIO);
1413 		--com->wopeners;
1414 		if (error != 0 || com->gone)
1415 			goto out;
1416 		goto open_top;
1417 	}
1418 	error =	(*linesw[tp->t_line].l_open)(dev, tp);
1419 	disc_optim(tp, &tp->t_termios, com);
1420 	if (tp->t_state & TS_ISOPEN && mynor & CALLOUT_MASK)
1421 		com->active_out = TRUE;
1422 	siosettimeout();
1423 out:
1424 	crit_exit();
1425 	if (!(tp->t_state & TS_ISOPEN) && com->wopeners == 0)
1426 		comhardclose(com);
1427 	return (error);
1428 }
1429 
1430 static int
1431 sioclose(dev_t dev, int	flag, int mode, struct thread *td)
1432 {
1433 	struct com_s	*com;
1434 	int		mynor;
1435 	struct tty	*tp;
1436 
1437 	mynor = minor(dev);
1438 	if (mynor & CONTROL_MASK)
1439 		return (0);
1440 	com = com_addr(MINOR_TO_UNIT(mynor));
1441 	if (com == NULL)
1442 		return (ENODEV);
1443 	tp = com->tp;
1444 	crit_enter();
1445 	(*linesw[tp->t_line].l_close)(tp, flag);
1446 	disc_optim(tp, &tp->t_termios, com);
1447 	comstop(tp, FREAD | FWRITE);
1448 	comhardclose(com);
1449 	ttyclose(tp);
1450 	siosettimeout();
1451 	crit_exit();
1452 	if (com->gone) {
1453 		printf("sio%d: gone\n", com->unit);
1454 		crit_enter();
1455 		if (com->ibuf != NULL)
1456 			free(com->ibuf, M_DEVBUF);
1457 		bzero(tp, sizeof *tp);
1458 		crit_exit();
1459 	}
1460 	return (0);
1461 }
1462 
1463 static void
1464 comhardclose(com)
1465 	struct com_s	*com;
1466 {
1467 	struct tty	*tp;
1468 	int		unit;
1469 
1470 	unit = com->unit;
1471 	crit_enter();
1472 	com->poll = FALSE;
1473 	com->poll_output = FALSE;
1474 	com->do_timestamp = FALSE;
1475 	com->do_dcd_timestamp = FALSE;
1476 	com->pps.ppsparam.mode = 0;
1477 	sio_setreg(com, com_cfcr, com->cfcr_image &= ~CFCR_SBREAK);
1478 	tp = com->tp;
1479 
1480 #if defined(DDB) && (defined(BREAK_TO_DEBUGGER) || \
1481     defined(ALT_BREAK_TO_DEBUGGER))
1482 	/*
1483 	 * Leave interrupts enabled and don't clear DTR if this is the
1484 	 * console. This allows us to detect break-to-debugger events
1485 	 * while the console device is closed.
1486 	 */
1487 	if (com->unit != comconsole)
1488 #endif
1489 	{
1490 		sio_setreg(com, com_ier, 0);
1491 		if (tp->t_cflag & HUPCL
1492 		    /*
1493 		     * XXX we will miss any carrier drop between here and the
1494 		     * next open.  Perhaps we should watch DCD even when the
1495 		     * port is closed; it is not sufficient to check it at
1496 		     * the next open because it might go up and down while
1497 		     * we're not watching.
1498 		     */
1499 		    || (!com->active_out
1500 		        && !(com->prev_modem_status & MSR_DCD)
1501 		        && !(com->it_in.c_cflag & CLOCAL))
1502 		    || !(tp->t_state & TS_ISOPEN)) {
1503 			(void)commctl(com, TIOCM_DTR, DMBIC);
1504 			if (com->dtr_wait != 0 && !(com->state & CS_DTR_OFF)) {
1505 				callout_reset(&com->dtr_ch, com->dtr_wait,
1506 						siodtrwakeup, com);
1507 				com->state |= CS_DTR_OFF;
1508 			}
1509 		}
1510 	}
1511 	if (com->hasfifo) {
1512 		/*
1513 		 * Disable fifos so that they are off after controlled
1514 		 * reboots.  Some BIOSes fail to detect 16550s when the
1515 		 * fifos are enabled.
1516 		 */
1517 		sio_setreg(com, com_fifo, 0);
1518 	}
1519 	com->active_out = FALSE;
1520 	wakeup(&com->active_out);
1521 	wakeup(TSA_CARR_ON(tp));	/* restart any wopeners */
1522 	crit_exit();
1523 }
1524 
1525 static int
1526 sioread(dev, uio, flag)
1527 	dev_t		dev;
1528 	struct uio	*uio;
1529 	int		flag;
1530 {
1531 	int		mynor;
1532 	struct com_s	*com;
1533 
1534 	mynor = minor(dev);
1535 	if (mynor & CONTROL_MASK)
1536 		return (ENODEV);
1537 	com = com_addr(MINOR_TO_UNIT(mynor));
1538 	if (com == NULL || com->gone)
1539 		return (ENODEV);
1540 	return ((*linesw[com->tp->t_line].l_read)(com->tp, uio, flag));
1541 }
1542 
1543 static int
1544 siowrite(dev, uio, flag)
1545 	dev_t		dev;
1546 	struct uio	*uio;
1547 	int		flag;
1548 {
1549 	int		mynor;
1550 	struct com_s	*com;
1551 	int		unit;
1552 
1553 	mynor = minor(dev);
1554 	if (mynor & CONTROL_MASK)
1555 		return (ENODEV);
1556 
1557 	unit = MINOR_TO_UNIT(mynor);
1558 	com = com_addr(unit);
1559 	if (com == NULL || com->gone)
1560 		return (ENODEV);
1561 	/*
1562 	 * (XXX) We disallow virtual consoles if the physical console is
1563 	 * a serial port.  This is in case there is a display attached that
1564 	 * is not the console.  In that situation we don't need/want the X
1565 	 * server taking over the console.
1566 	 */
1567 	if (constty != NULL && unit == comconsole)
1568 		constty = NULL;
1569 	return ((*linesw[com->tp->t_line].l_write)(com->tp, uio, flag));
1570 }
1571 
1572 static void
1573 siobusycheck(chan)
1574 	void	*chan;
1575 {
1576 	struct com_s	*com;
1577 
1578 	com = (struct com_s *)chan;
1579 
1580 	/*
1581 	 * Clear TS_BUSY if low-level output is complete.
1582 	 * spl locking is sufficient because siointr1() does not set CS_BUSY.
1583 	 * If siointr1() clears CS_BUSY after we look at it, then we'll get
1584 	 * called again.  Reading the line status port outside of siointr1()
1585 	 * is safe because CS_BUSY is clear so there are no output interrupts
1586 	 * to lose.
1587 	 */
1588 	crit_enter();
1589 	if (com->state & CS_BUSY)
1590 		com->extra_state &= ~CSE_BUSYCHECK;	/* False alarm. */
1591 	else if ((inb(com->line_status_port) & (LSR_TSRE | LSR_TXRDY))
1592 	    == (LSR_TSRE | LSR_TXRDY)) {
1593 		com->tp->t_state &= ~TS_BUSY;
1594 		ttwwakeup(com->tp);
1595 		com->extra_state &= ~CSE_BUSYCHECK;
1596 	} else {
1597 		callout_reset(&com->busy_ch, hz / 100, siobusycheck, com);
1598 	}
1599 	crit_exit();
1600 }
1601 
1602 static u_int
1603 siodivisor(rclk, speed)
1604 	u_long	rclk;
1605 	speed_t	speed;
1606 {
1607 	long	actual_speed;
1608 	u_int	divisor;
1609 	int	error;
1610 
1611 	if (speed == 0 || speed > (ULONG_MAX - 1) / 8)
1612 		return (0);
1613 	divisor = (rclk / (8UL * speed) + 1) / 2;
1614 	if (divisor == 0 || divisor >= 65536)
1615 		return (0);
1616 	actual_speed = rclk / (16UL * divisor);
1617 
1618 	/* 10 times error in percent: */
1619 	error = ((actual_speed - (long)speed) * 2000 / (long)speed + 1) / 2;
1620 
1621 	/* 3.0% maximum error tolerance: */
1622 	if (error < -30 || error > 30)
1623 		return (0);
1624 
1625 	return (divisor);
1626 }
1627 
1628 static void
1629 siodtrwakeup(chan)
1630 	void	*chan;
1631 {
1632 	struct com_s	*com;
1633 
1634 	com = (struct com_s *)chan;
1635 	com->state &= ~CS_DTR_OFF;
1636 	wakeup(&com->dtr_wait);
1637 }
1638 
1639 static void
1640 sioinput(com)
1641 	struct com_s	*com;
1642 {
1643 	u_char		*buf;
1644 	int		incc;
1645 	u_char		line_status;
1646 	int		recv_data;
1647 	struct tty	*tp;
1648 
1649 	buf = com->ibuf;
1650 	tp = com->tp;
1651 	if (!(tp->t_state & TS_ISOPEN) || !(tp->t_cflag & CREAD)) {
1652 		com_events -= (com->iptr - com->ibuf);
1653 		com->iptr = com->ibuf;
1654 		return;
1655 	}
1656 	if (tp->t_state & TS_CAN_BYPASS_L_RINT) {
1657 		/*
1658 		 * Avoid the grotesquely inefficient lineswitch routine
1659 		 * (ttyinput) in "raw" mode.  It usually takes about 450
1660 		 * instructions (that's without canonical processing or echo!).
1661 		 * slinput is reasonably fast (usually 40 instructions plus
1662 		 * call overhead).
1663 		 */
1664 		do {
1665 			com_unlock();
1666 			incc = com->iptr - buf;
1667 			if (tp->t_rawq.c_cc + incc > tp->t_ihiwat
1668 			    && (com->state & CS_RTS_IFLOW
1669 				|| tp->t_iflag & IXOFF)
1670 			    && !(tp->t_state & TS_TBLOCK))
1671 				ttyblock(tp);
1672 			com->delta_error_counts[CE_TTY_BUF_OVERFLOW]
1673 				+= b_to_q((char *)buf, incc, &tp->t_rawq);
1674 			buf += incc;
1675 			tk_nin += incc;
1676 			tk_rawcc += incc;
1677 			tp->t_rawcc += incc;
1678 			ttwakeup(tp);
1679 			if (tp->t_state & TS_TTSTOP
1680 			    && (tp->t_iflag & IXANY
1681 				|| tp->t_cc[VSTART] == tp->t_cc[VSTOP])) {
1682 				tp->t_state &= ~TS_TTSTOP;
1683 				tp->t_lflag &= ~FLUSHO;
1684 				comstart(tp);
1685 			}
1686 			com_lock();
1687 		} while (buf < com->iptr);
1688 	} else {
1689 		do {
1690 			com_unlock();
1691 			line_status = buf[com->ierroff];
1692 			recv_data = *buf++;
1693 			if (line_status
1694 			    & (LSR_BI | LSR_FE | LSR_OE | LSR_PE)) {
1695 				if (line_status & LSR_BI)
1696 					recv_data |= TTY_BI;
1697 				if (line_status & LSR_FE)
1698 					recv_data |= TTY_FE;
1699 				if (line_status & LSR_OE)
1700 					recv_data |= TTY_OE;
1701 				if (line_status & LSR_PE)
1702 					recv_data |= TTY_PE;
1703 			}
1704 			(*linesw[tp->t_line].l_rint)(recv_data, tp);
1705 			com_lock();
1706 		} while (buf < com->iptr);
1707 	}
1708 	com_events -= (com->iptr - com->ibuf);
1709 	com->iptr = com->ibuf;
1710 
1711 	/*
1712 	 * There is now room for another low-level buffer full of input,
1713 	 * so enable RTS if it is now disabled and there is room in the
1714 	 * high-level buffer.
1715 	 */
1716 	if ((com->state & CS_RTS_IFLOW) && !(com->mcr_image & MCR_RTS) &&
1717 	    !(tp->t_state & TS_TBLOCK))
1718 		outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
1719 }
1720 
1721 void
1722 siointr(arg)
1723 	void		*arg;
1724 {
1725 #ifndef COM_MULTIPORT
1726 	com_lock();
1727 	siointr1((struct com_s *) arg);
1728 	com_unlock();
1729 #else /* COM_MULTIPORT */
1730 	bool_t		possibly_more_intrs;
1731 	int		unit;
1732 	struct com_s	*com;
1733 
1734 	/*
1735 	 * Loop until there is no activity on any port.  This is necessary
1736 	 * to get an interrupt edge more than to avoid another interrupt.
1737 	 * If the IRQ signal is just an OR of the IRQ signals from several
1738 	 * devices, then the edge from one may be lost because another is
1739 	 * on.
1740 	 */
1741 	com_lock();
1742 	do {
1743 		possibly_more_intrs = FALSE;
1744 		for (unit = 0; unit < sio_numunits; ++unit) {
1745 			com = com_addr(unit);
1746 			/*
1747 			 * XXX com_lock();
1748 			 * would it work here, or be counter-productive?
1749 			 */
1750 			if (com != NULL
1751 			    && !com->gone
1752 			    && (inb(com->int_id_port) & IIR_IMASK)
1753 			       != IIR_NOPEND) {
1754 				siointr1(com);
1755 				possibly_more_intrs = TRUE;
1756 			}
1757 			/* XXX com_unlock(); */
1758 		}
1759 	} while (possibly_more_intrs);
1760 	com_unlock();
1761 #endif /* COM_MULTIPORT */
1762 }
1763 
1764 static void
1765 siointr1(com)
1766 	struct com_s	*com;
1767 {
1768 	u_char	line_status;
1769 	u_char	modem_status;
1770 	u_char	*ioptr;
1771 	u_char	recv_data;
1772 	u_char	int_ctl;
1773 	u_char	int_ctl_new;
1774 	u_int	count;
1775 
1776 	int_ctl = inb(com->intr_ctl_port);
1777 	int_ctl_new = int_ctl;
1778 
1779 	while (!com->gone) {
1780 		if (com->pps.ppsparam.mode & PPS_CAPTUREBOTH) {
1781 			modem_status = inb(com->modem_status_port);
1782 		        if ((modem_status ^ com->last_modem_status) & MSR_DCD) {
1783 				count = sys_cputimer->count();
1784 				pps_event(&com->pps, count,
1785 				    (modem_status & MSR_DCD) ?
1786 				    PPS_CAPTUREASSERT : PPS_CAPTURECLEAR);
1787 			}
1788 		}
1789 		line_status = inb(com->line_status_port);
1790 
1791 		/* input event? (check first to help avoid overruns) */
1792 		while (line_status & LSR_RCV_MASK) {
1793 			/* break/unnattached error bits or real input? */
1794 			if (!(line_status & LSR_RXRDY))
1795 				recv_data = 0;
1796 			else
1797 				recv_data = inb(com->data_port);
1798 #if defined(DDB) && defined(ALT_BREAK_TO_DEBUGGER)
1799 			/*
1800 			 * Solaris implements a new BREAK which is initiated
1801 			 * by a character sequence CR ~ ^b which is similar
1802 			 * to a familiar pattern used on Sun servers by the
1803 			 * Remote Console.
1804 			 */
1805 #define	KEY_CRTLB	2	/* ^B */
1806 #define	KEY_CR		13	/* CR '\r' */
1807 #define	KEY_TILDE	126	/* ~ */
1808 
1809 			if (com->unit == comconsole) {
1810 				static int brk_state1 = 0, brk_state2 = 0;
1811 				if (recv_data == KEY_CR) {
1812 					brk_state1 = recv_data;
1813 					brk_state2 = 0;
1814 				} else if (brk_state1 == KEY_CR && (recv_data == KEY_TILDE || recv_data == KEY_CRTLB)) {
1815 					if (recv_data == KEY_TILDE)
1816 						brk_state2 = recv_data;
1817 					else if (brk_state2 == KEY_TILDE && recv_data == KEY_CRTLB) {
1818 							breakpoint();
1819 							brk_state1 = brk_state2 = 0;
1820 							goto cont;
1821 					} else
1822 						brk_state2 = 0;
1823 				} else
1824 					brk_state1 = 0;
1825 			}
1826 #endif
1827 			if (line_status & (LSR_BI | LSR_FE | LSR_PE)) {
1828 				/*
1829 				 * Don't store BI if IGNBRK or FE/PE if IGNPAR.
1830 				 * Otherwise, push the work to a higher level
1831 				 * (to handle PARMRK) if we're bypassing.
1832 				 * Otherwise, convert BI/FE and PE+INPCK to 0.
1833 				 *
1834 				 * This makes bypassing work right in the
1835 				 * usual "raw" case (IGNBRK set, and IGNPAR
1836 				 * and INPCK clear).
1837 				 *
1838 				 * Note: BI together with FE/PE means just BI.
1839 				 */
1840 				if (line_status & LSR_BI) {
1841 #if defined(DDB) && defined(BREAK_TO_DEBUGGER)
1842 					if (com->unit == comconsole) {
1843 						breakpoint();
1844 						goto cont;
1845 					}
1846 #endif
1847 					if (com->tp == NULL
1848 					    || com->tp->t_iflag & IGNBRK)
1849 						goto cont;
1850 				} else {
1851 					if (com->tp == NULL
1852 					    || com->tp->t_iflag & IGNPAR)
1853 						goto cont;
1854 				}
1855 				if (com->tp->t_state & TS_CAN_BYPASS_L_RINT
1856 				    && (line_status & (LSR_BI | LSR_FE)
1857 					|| com->tp->t_iflag & INPCK))
1858 					recv_data = 0;
1859 			}
1860 			++com->bytes_in;
1861 			if (com->hotchar != 0 && recv_data == com->hotchar)
1862 				setsofttty();
1863 			ioptr = com->iptr;
1864 			if (ioptr >= com->ibufend)
1865 				CE_RECORD(com, CE_INTERRUPT_BUF_OVERFLOW);
1866 			else {
1867 				if (com->do_timestamp)
1868 					microtime(&com->timestamp);
1869 				++com_events;
1870 				schedsofttty();
1871 #if 0 /* for testing input latency vs efficiency */
1872 if (com->iptr - com->ibuf == 8)
1873 	setsofttty();
1874 #endif
1875 				ioptr[0] = recv_data;
1876 				ioptr[com->ierroff] = line_status;
1877 				com->iptr = ++ioptr;
1878 				if (ioptr == com->ihighwater
1879 				    && com->state & CS_RTS_IFLOW)
1880 					outb(com->modem_ctl_port,
1881 					     com->mcr_image &= ~MCR_RTS);
1882 				if (line_status & LSR_OE)
1883 					CE_RECORD(com, CE_OVERRUN);
1884 			}
1885 cont:
1886 			/*
1887 			 * "& 0x7F" is to avoid the gcc-1.40 generating a slow
1888 			 * jump from the top of the loop to here
1889 			 */
1890 			line_status = inb(com->line_status_port) & 0x7F;
1891 		}
1892 
1893 		/* modem status change? (always check before doing output) */
1894 		modem_status = inb(com->modem_status_port);
1895 		if (modem_status != com->last_modem_status) {
1896 			if (com->do_dcd_timestamp
1897 			    && !(com->last_modem_status & MSR_DCD)
1898 			    && modem_status & MSR_DCD)
1899 				microtime(&com->dcd_timestamp);
1900 
1901 			/*
1902 			 * Schedule high level to handle DCD changes.  Note
1903 			 * that we don't use the delta bits anywhere.  Some
1904 			 * UARTs mess them up, and it's easy to remember the
1905 			 * previous bits and calculate the delta.
1906 			 */
1907 			com->last_modem_status = modem_status;
1908 			if (!(com->state & CS_CHECKMSR)) {
1909 				com_events += LOTS_OF_EVENTS;
1910 				com->state |= CS_CHECKMSR;
1911 				setsofttty();
1912 			}
1913 
1914 			/* handle CTS change immediately for crisp flow ctl */
1915 			if (com->state & CS_CTS_OFLOW) {
1916 				if (modem_status & MSR_CTS)
1917 					com->state |= CS_ODEVREADY;
1918 				else
1919 					com->state &= ~CS_ODEVREADY;
1920 			}
1921 		}
1922 
1923 		/* output queued and everything ready? */
1924 		if (line_status & LSR_TXRDY
1925 		    && com->state >= (CS_BUSY | CS_TTGO | CS_ODEVREADY)) {
1926 			ioptr = com->obufq.l_head;
1927 			if (com->tx_fifo_size > 1) {
1928 				u_int	ocount;
1929 
1930 				ocount = com->obufq.l_tail - ioptr;
1931 				if (ocount > com->tx_fifo_size)
1932 					ocount = com->tx_fifo_size;
1933 				com->bytes_out += ocount;
1934 				do
1935 					outb(com->data_port, *ioptr++);
1936 				while (--ocount != 0);
1937 			} else {
1938 				outb(com->data_port, *ioptr++);
1939 				++com->bytes_out;
1940 			}
1941 			com->obufq.l_head = ioptr;
1942 			if (COM_IIR_TXRDYBUG(com->flags)) {
1943 				int_ctl_new = int_ctl | IER_ETXRDY;
1944 			}
1945 			if (ioptr >= com->obufq.l_tail) {
1946 				struct lbq	*qp;
1947 
1948 				qp = com->obufq.l_next;
1949 				qp->l_queued = FALSE;
1950 				qp = qp->l_next;
1951 				if (qp != NULL) {
1952 					com->obufq.l_head = qp->l_head;
1953 					com->obufq.l_tail = qp->l_tail;
1954 					com->obufq.l_next = qp;
1955 				} else {
1956 					/* output just completed */
1957 					if (COM_IIR_TXRDYBUG(com->flags)) {
1958 						int_ctl_new = int_ctl & ~IER_ETXRDY;
1959 					}
1960 					com->state &= ~CS_BUSY;
1961 				}
1962 				if (!(com->state & CS_ODONE)) {
1963 					com_events += LOTS_OF_EVENTS;
1964 					com->state |= CS_ODONE;
1965 					setsofttty();	/* handle at high level ASAP */
1966 				}
1967 			}
1968 			if (COM_IIR_TXRDYBUG(com->flags) && (int_ctl != int_ctl_new)) {
1969 				outb(com->intr_ctl_port, int_ctl_new);
1970 			}
1971 		}
1972 
1973 		/* finished? */
1974 #ifndef COM_MULTIPORT
1975 		if ((inb(com->int_id_port) & IIR_IMASK) == IIR_NOPEND)
1976 #endif /* COM_MULTIPORT */
1977 			return;
1978 	}
1979 }
1980 
1981 static int
1982 sioioctl(dev_t dev, u_long cmd, caddr_t	data, int flag, struct thread *td)
1983 {
1984 	struct com_s	*com;
1985 	int		error;
1986 	int		mynor;
1987 	struct tty	*tp;
1988 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
1989 	u_long		oldcmd;
1990 	struct termios	term;
1991 #endif
1992 
1993 	mynor = minor(dev);
1994 	com = com_addr(MINOR_TO_UNIT(mynor));
1995 	if (com == NULL || com->gone)
1996 		return (ENODEV);
1997 	if (mynor & CONTROL_MASK) {
1998 		struct termios	*ct;
1999 
2000 		switch (mynor & CONTROL_MASK) {
2001 		case CONTROL_INIT_STATE:
2002 			ct = mynor & CALLOUT_MASK ? &com->it_out : &com->it_in;
2003 			break;
2004 		case CONTROL_LOCK_STATE:
2005 			ct = mynor & CALLOUT_MASK ? &com->lt_out : &com->lt_in;
2006 			break;
2007 		default:
2008 			return (ENODEV);	/* /dev/nodev */
2009 		}
2010 		switch (cmd) {
2011 		case TIOCSETA:
2012 			error = suser(td);
2013 			if (error != 0)
2014 				return (error);
2015 			*ct = *(struct termios *)data;
2016 			return (0);
2017 		case TIOCGETA:
2018 			*(struct termios *)data = *ct;
2019 			return (0);
2020 		case TIOCGETD:
2021 			*(int *)data = TTYDISC;
2022 			return (0);
2023 		case TIOCGWINSZ:
2024 			bzero(data, sizeof(struct winsize));
2025 			return (0);
2026 		default:
2027 			return (ENOTTY);
2028 		}
2029 	}
2030 	tp = com->tp;
2031 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
2032 	term = tp->t_termios;
2033 	oldcmd = cmd;
2034 	error = ttsetcompat(tp, &cmd, data, &term);
2035 	if (error != 0)
2036 		return (error);
2037 	if (cmd != oldcmd)
2038 		data = (caddr_t)&term;
2039 #endif
2040 	if (cmd == TIOCSETA || cmd == TIOCSETAW || cmd == TIOCSETAF) {
2041 		int	cc;
2042 		struct termios *dt = (struct termios *)data;
2043 		struct termios *lt = mynor & CALLOUT_MASK
2044 				     ? &com->lt_out : &com->lt_in;
2045 
2046 		dt->c_iflag = (tp->t_iflag & lt->c_iflag)
2047 			      | (dt->c_iflag & ~lt->c_iflag);
2048 		dt->c_oflag = (tp->t_oflag & lt->c_oflag)
2049 			      | (dt->c_oflag & ~lt->c_oflag);
2050 		dt->c_cflag = (tp->t_cflag & lt->c_cflag)
2051 			      | (dt->c_cflag & ~lt->c_cflag);
2052 		dt->c_lflag = (tp->t_lflag & lt->c_lflag)
2053 			      | (dt->c_lflag & ~lt->c_lflag);
2054 		for (cc = 0; cc < NCCS; ++cc)
2055 			if (lt->c_cc[cc] != 0)
2056 				dt->c_cc[cc] = tp->t_cc[cc];
2057 		if (lt->c_ispeed != 0)
2058 			dt->c_ispeed = tp->t_ispeed;
2059 		if (lt->c_ospeed != 0)
2060 			dt->c_ospeed = tp->t_ospeed;
2061 	}
2062 	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, td);
2063 	if (error != ENOIOCTL)
2064 		return (error);
2065 	crit_enter();
2066 	error = ttioctl(tp, cmd, data, flag);
2067 	disc_optim(tp, &tp->t_termios, com);
2068 	if (error != ENOIOCTL) {
2069 		crit_exit();
2070 		return (error);
2071 	}
2072 	switch (cmd) {
2073 	case TIOCSBRK:
2074 		sio_setreg(com, com_cfcr, com->cfcr_image |= CFCR_SBREAK);
2075 		break;
2076 	case TIOCCBRK:
2077 		sio_setreg(com, com_cfcr, com->cfcr_image &= ~CFCR_SBREAK);
2078 		break;
2079 	case TIOCSDTR:
2080 		(void)commctl(com, TIOCM_DTR, DMBIS);
2081 		break;
2082 	case TIOCCDTR:
2083 		(void)commctl(com, TIOCM_DTR, DMBIC);
2084 		break;
2085 	/*
2086 	 * XXX should disallow changing MCR_RTS if CS_RTS_IFLOW is set.  The
2087 	 * changes get undone on the next call to comparam().
2088 	 */
2089 	case TIOCMSET:
2090 		(void)commctl(com, *(int *)data, DMSET);
2091 		break;
2092 	case TIOCMBIS:
2093 		(void)commctl(com, *(int *)data, DMBIS);
2094 		break;
2095 	case TIOCMBIC:
2096 		(void)commctl(com, *(int *)data, DMBIC);
2097 		break;
2098 	case TIOCMGET:
2099 		*(int *)data = commctl(com, 0, DMGET);
2100 		break;
2101 	case TIOCMSDTRWAIT:
2102 		/* must be root since the wait applies to following logins */
2103 		error = suser(td);
2104 		if (error != 0) {
2105 			crit_exit();
2106 			return (error);
2107 		}
2108 		com->dtr_wait = *(int *)data * hz / 100;
2109 		break;
2110 	case TIOCMGDTRWAIT:
2111 		*(int *)data = com->dtr_wait * 100 / hz;
2112 		break;
2113 	case TIOCTIMESTAMP:
2114 		com->do_timestamp = TRUE;
2115 		*(struct timeval *)data = com->timestamp;
2116 		break;
2117 	case TIOCDCDTIMESTAMP:
2118 		com->do_dcd_timestamp = TRUE;
2119 		*(struct timeval *)data = com->dcd_timestamp;
2120 		break;
2121 	default:
2122 		crit_exit();
2123 		error = pps_ioctl(cmd, data, &com->pps);
2124 		if (error == ENODEV)
2125 			error = ENOTTY;
2126 		return (error);
2127 	}
2128 	crit_exit();
2129 	return (0);
2130 }
2131 
2132 static void
2133 siopoll(void *dummy)
2134 {
2135 	int		unit;
2136 
2137 	if (com_events == 0)
2138 		return;
2139 repeat:
2140 	for (unit = 0; unit < sio_numunits; ++unit) {
2141 		struct com_s	*com;
2142 		int		incc;
2143 		struct tty	*tp;
2144 
2145 		com = com_addr(unit);
2146 		if (com == NULL)
2147 			continue;
2148 		tp = com->tp;
2149 		if (tp == NULL || com->gone) {
2150 			/*
2151 			 * Discard any events related to never-opened or
2152 			 * going-away devices.
2153 			 */
2154 			com_lock();
2155 			incc = com->iptr - com->ibuf;
2156 			com->iptr = com->ibuf;
2157 			if (com->state & CS_CHECKMSR) {
2158 				incc += LOTS_OF_EVENTS;
2159 				com->state &= ~CS_CHECKMSR;
2160 			}
2161 			com_events -= incc;
2162 			com_unlock();
2163 			continue;
2164 		}
2165 		if (com->iptr != com->ibuf) {
2166 			com_lock();
2167 			sioinput(com);
2168 			com_unlock();
2169 		}
2170 		if (com->state & CS_CHECKMSR) {
2171 			u_char	delta_modem_status;
2172 
2173 			com_lock();
2174 			delta_modem_status = com->last_modem_status
2175 					     ^ com->prev_modem_status;
2176 			com->prev_modem_status = com->last_modem_status;
2177 			com_events -= LOTS_OF_EVENTS;
2178 			com->state &= ~CS_CHECKMSR;
2179 			com_unlock();
2180 			if (delta_modem_status & MSR_DCD)
2181 				(*linesw[tp->t_line].l_modem)
2182 					(tp, com->prev_modem_status & MSR_DCD);
2183 		}
2184 		if (com->state & CS_ODONE) {
2185 			com_lock();
2186 			com_events -= LOTS_OF_EVENTS;
2187 			com->state &= ~CS_ODONE;
2188 			com_unlock();
2189 			if (!(com->state & CS_BUSY)
2190 			    && !(com->extra_state & CSE_BUSYCHECK)) {
2191 				callout_reset(&com->busy_ch, hz / 100,
2192 						siobusycheck, com);
2193 				com->extra_state |= CSE_BUSYCHECK;
2194 			}
2195 			(*linesw[tp->t_line].l_start)(tp);
2196 		}
2197 		if (com_events == 0)
2198 			break;
2199 	}
2200 	if (com_events >= LOTS_OF_EVENTS)
2201 		goto repeat;
2202 }
2203 
2204 static int
2205 comparam(tp, t)
2206 	struct tty	*tp;
2207 	struct termios	*t;
2208 {
2209 	u_int		cfcr;
2210 	int		cflag;
2211 	struct com_s	*com;
2212 	u_int		divisor;
2213 	u_char		dlbh;
2214 	u_char		dlbl;
2215 	int		unit;
2216 
2217 	unit = DEV_TO_UNIT(tp->t_dev);
2218 	com = com_addr(unit);
2219 	if (com == NULL)
2220 		return (ENODEV);
2221 
2222 	/* do historical conversions */
2223 	if (t->c_ispeed == 0)
2224 		t->c_ispeed = t->c_ospeed;
2225 
2226 	/* check requested parameters */
2227 	if (t->c_ospeed == 0)
2228 		divisor = 0;
2229 	else {
2230 		if (t->c_ispeed != t->c_ospeed)
2231 			return (EINVAL);
2232 		divisor = siodivisor(com->rclk, t->c_ispeed);
2233 		if (divisor == 0)
2234 			return (EINVAL);
2235 	}
2236 
2237 	/* parameters are OK, convert them to the com struct and the device */
2238 	crit_enter();
2239 	if (divisor == 0)
2240 		(void)commctl(com, TIOCM_DTR, DMBIC);	/* hang up line */
2241 	else
2242 		(void)commctl(com, TIOCM_DTR, DMBIS);
2243 	cflag = t->c_cflag;
2244 	switch (cflag & CSIZE) {
2245 	case CS5:
2246 		cfcr = CFCR_5BITS;
2247 		break;
2248 	case CS6:
2249 		cfcr = CFCR_6BITS;
2250 		break;
2251 	case CS7:
2252 		cfcr = CFCR_7BITS;
2253 		break;
2254 	default:
2255 		cfcr = CFCR_8BITS;
2256 		break;
2257 	}
2258 	if (cflag & PARENB) {
2259 		cfcr |= CFCR_PENAB;
2260 		if (!(cflag & PARODD))
2261 			cfcr |= CFCR_PEVEN;
2262 	}
2263 	if (cflag & CSTOPB)
2264 		cfcr |= CFCR_STOPB;
2265 
2266 	if (com->hasfifo && divisor != 0) {
2267 		/*
2268 		 * Use a fifo trigger level low enough so that the input
2269 		 * latency from the fifo is less than about 16 msec and
2270 		 * the total latency is less than about 30 msec.  These
2271 		 * latencies are reasonable for humans.  Serial comms
2272 		 * protocols shouldn't expect anything better since modem
2273 		 * latencies are larger.
2274 		 *
2275 		 * Interrupts can be held up for long periods of time
2276 		 * due to inefficiencies in other parts of the kernel,
2277 		 * certain video cards, etc.  Setting the FIFO trigger
2278 		 * point to MEDH instead of HIGH gives us 694uS of slop
2279 		 * (8 character times) instead of 173uS (2 character times)
2280 		 * @ 115200 bps.
2281 		 */
2282 		com->fifo_image = t->c_ospeed <= 4800
2283 				  ? FIFO_ENABLE : FIFO_ENABLE | FIFO_RX_MEDH;
2284 #ifdef COM_ESP
2285 		/*
2286 		 * The Hayes ESP card needs the fifo DMA mode bit set
2287 		 * in compatibility mode.  If not, it will interrupt
2288 		 * for each character received.
2289 		 */
2290 		if (com->esp)
2291 			com->fifo_image |= FIFO_DMA_MODE;
2292 #endif
2293 		sio_setreg(com, com_fifo, com->fifo_image);
2294 	}
2295 
2296 	/*
2297 	 * This returns with interrupts disabled so that we can complete
2298 	 * the speed change atomically.  Keeping interrupts disabled is
2299 	 * especially important while com_data is hidden.
2300 	 */
2301 	(void) siosetwater(com, t->c_ispeed);
2302 
2303 	if (divisor != 0) {
2304 		sio_setreg(com, com_cfcr, cfcr | CFCR_DLAB);
2305 		/*
2306 		 * Only set the divisor registers if they would change,
2307 		 * since on some 16550 incompatibles (UMC8669F), setting
2308 		 * them while input is arriving them loses sync until
2309 		 * data stops arriving.
2310 		 */
2311 		dlbl = divisor & 0xFF;
2312 		if (sio_getreg(com, com_dlbl) != dlbl)
2313 			sio_setreg(com, com_dlbl, dlbl);
2314 		dlbh = divisor >> 8;
2315 		if (sio_getreg(com, com_dlbh) != dlbh)
2316 			sio_setreg(com, com_dlbh, dlbh);
2317 	}
2318 
2319 	sio_setreg(com, com_cfcr, com->cfcr_image = cfcr);
2320 
2321 	if (!(tp->t_state & TS_TTSTOP))
2322 		com->state |= CS_TTGO;
2323 
2324 	if (cflag & CRTS_IFLOW) {
2325 		if (com->st16650a) {
2326 			sio_setreg(com, com_cfcr, 0xbf);
2327 			sio_setreg(com, com_fifo,
2328 				   sio_getreg(com, com_fifo) | 0x40);
2329 		}
2330 		com->state |= CS_RTS_IFLOW;
2331 		/*
2332 		 * If CS_RTS_IFLOW just changed from off to on, the change
2333 		 * needs to be propagated to MCR_RTS.  This isn't urgent,
2334 		 * so do it later by calling comstart() instead of repeating
2335 		 * a lot of code from comstart() here.
2336 		 */
2337 	} else if (com->state & CS_RTS_IFLOW) {
2338 		com->state &= ~CS_RTS_IFLOW;
2339 		/*
2340 		 * CS_RTS_IFLOW just changed from on to off.  Force MCR_RTS
2341 		 * on here, since comstart() won't do it later.
2342 		 */
2343 		outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
2344 		if (com->st16650a) {
2345 			sio_setreg(com, com_cfcr, 0xbf);
2346 			sio_setreg(com, com_fifo,
2347 				   sio_getreg(com, com_fifo) & ~0x40);
2348 		}
2349 	}
2350 
2351 
2352 	/*
2353 	 * Set up state to handle output flow control.
2354 	 * XXX - worth handling MDMBUF (DCD) flow control at the lowest level?
2355 	 * Now has 10+ msec latency, while CTS flow has 50- usec latency.
2356 	 */
2357 	com->state |= CS_ODEVREADY;
2358 	com->state &= ~CS_CTS_OFLOW;
2359 	if (cflag & CCTS_OFLOW) {
2360 		com->state |= CS_CTS_OFLOW;
2361 		if (!(com->last_modem_status & MSR_CTS))
2362 			com->state &= ~CS_ODEVREADY;
2363 		if (com->st16650a) {
2364 			sio_setreg(com, com_cfcr, 0xbf);
2365 			sio_setreg(com, com_fifo,
2366 				   sio_getreg(com, com_fifo) | 0x80);
2367 		}
2368 	} else {
2369 		if (com->st16650a) {
2370 			sio_setreg(com, com_cfcr, 0xbf);
2371 			sio_setreg(com, com_fifo,
2372 				   sio_getreg(com, com_fifo) & ~0x80);
2373 		}
2374 	}
2375 
2376 	sio_setreg(com, com_cfcr, com->cfcr_image);
2377 
2378 	/* XXX shouldn't call functions while intrs are disabled. */
2379 	disc_optim(tp, t, com);
2380 	/*
2381 	 * Recover from fiddling with CS_TTGO.  We used to call siointr1()
2382 	 * unconditionally, but that defeated the careful discarding of
2383 	 * stale input in sioopen().
2384 	 */
2385 	if (com->state >= (CS_BUSY | CS_TTGO))
2386 		siointr1(com);
2387 
2388 	com_unlock();
2389 	crit_exit();
2390 	comstart(tp);
2391 	if (com->ibufold != NULL) {
2392 		free(com->ibufold, M_DEVBUF);
2393 		com->ibufold = NULL;
2394 	}
2395 	return (0);
2396 }
2397 
2398 static int
2399 siosetwater(com, speed)
2400 	struct com_s	*com;
2401 	speed_t		speed;
2402 {
2403 	int		cp4ticks;
2404 	u_char		*ibuf;
2405 	int		ibufsize;
2406 	struct tty	*tp;
2407 
2408 	/*
2409 	 * Make the buffer size large enough to handle a softtty interrupt
2410 	 * latency of about 2 ticks without loss of throughput or data
2411 	 * (about 3 ticks if input flow control is not used or not honoured,
2412 	 * but a bit less for CS5-CS7 modes).
2413 	 */
2414 	cp4ticks = speed / 10 / hz * 4;
2415 	for (ibufsize = 128; ibufsize < cp4ticks;)
2416 		ibufsize <<= 1;
2417 	if (ibufsize == com->ibufsize) {
2418 		com_lock();
2419 		return (0);
2420 	}
2421 
2422 	/*
2423 	 * Allocate input buffer.  The extra factor of 2 in the size is
2424 	 * to allow for an error byte for each input byte.
2425 	 */
2426 	ibuf = malloc(2 * ibufsize, M_DEVBUF, M_WAITOK | M_ZERO);
2427 
2428 	/* Initialize non-critical variables. */
2429 	com->ibufold = com->ibuf;
2430 	com->ibufsize = ibufsize;
2431 	tp = com->tp;
2432 	if (tp != NULL) {
2433 		tp->t_ififosize = 2 * ibufsize;
2434 		tp->t_ispeedwat = (speed_t)-1;
2435 		tp->t_ospeedwat = (speed_t)-1;
2436 	}
2437 
2438 	/*
2439 	 * Read current input buffer, if any.  Continue with interrupts
2440 	 * disabled.
2441 	 */
2442 	com_lock();
2443 	if (com->iptr != com->ibuf)
2444 		sioinput(com);
2445 
2446 	/*-
2447 	 * Initialize critical variables, including input buffer watermarks.
2448 	 * The external device is asked to stop sending when the buffer
2449 	 * exactly reaches high water, or when the high level requests it.
2450 	 * The high level is notified immediately (rather than at a later
2451 	 * clock tick) when this watermark is reached.
2452 	 * The buffer size is chosen so the watermark should almost never
2453 	 * be reached.
2454 	 * The low watermark is invisibly 0 since the buffer is always
2455 	 * emptied all at once.
2456 	 */
2457 	com->iptr = com->ibuf = ibuf;
2458 	com->ibufend = ibuf + ibufsize;
2459 	com->ierroff = ibufsize;
2460 	com->ihighwater = ibuf + 3 * ibufsize / 4;
2461 	return (0);
2462 }
2463 
2464 static void
2465 comstart(tp)
2466 	struct tty	*tp;
2467 {
2468 	struct com_s	*com;
2469 	int		unit;
2470 
2471 	unit = DEV_TO_UNIT(tp->t_dev);
2472 	com = com_addr(unit);
2473 	if (com == NULL)
2474 		return;
2475 	crit_enter();
2476 	com_lock();
2477 	if (tp->t_state & TS_TTSTOP)
2478 		com->state &= ~CS_TTGO;
2479 	else
2480 		com->state |= CS_TTGO;
2481 	if (tp->t_state & TS_TBLOCK) {
2482 		if (com->mcr_image & MCR_RTS && com->state & CS_RTS_IFLOW)
2483 			outb(com->modem_ctl_port, com->mcr_image &= ~MCR_RTS);
2484 	} else {
2485 		if (!(com->mcr_image & MCR_RTS) && com->iptr < com->ihighwater
2486 		    && com->state & CS_RTS_IFLOW)
2487 			outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
2488 	}
2489 	com_unlock();
2490 	if (tp->t_state & (TS_TIMEOUT | TS_TTSTOP)) {
2491 		ttwwakeup(tp);
2492 		crit_exit();
2493 		return;
2494 	}
2495 	if (tp->t_outq.c_cc != 0) {
2496 		struct lbq	*qp;
2497 		struct lbq	*next;
2498 
2499 		if (!com->obufs[0].l_queued) {
2500 			com->obufs[0].l_tail
2501 			    = com->obuf1 + q_to_b(&tp->t_outq, com->obuf1,
2502 						  sizeof com->obuf1);
2503 			com->obufs[0].l_next = NULL;
2504 			com->obufs[0].l_queued = TRUE;
2505 			com_lock();
2506 			if (com->state & CS_BUSY) {
2507 				qp = com->obufq.l_next;
2508 				while ((next = qp->l_next) != NULL)
2509 					qp = next;
2510 				qp->l_next = &com->obufs[0];
2511 			} else {
2512 				com->obufq.l_head = com->obufs[0].l_head;
2513 				com->obufq.l_tail = com->obufs[0].l_tail;
2514 				com->obufq.l_next = &com->obufs[0];
2515 				com->state |= CS_BUSY;
2516 			}
2517 			com_unlock();
2518 		}
2519 		if (tp->t_outq.c_cc != 0 && !com->obufs[1].l_queued) {
2520 			com->obufs[1].l_tail
2521 			    = com->obuf2 + q_to_b(&tp->t_outq, com->obuf2,
2522 						  sizeof com->obuf2);
2523 			com->obufs[1].l_next = NULL;
2524 			com->obufs[1].l_queued = TRUE;
2525 			com_lock();
2526 			if (com->state & CS_BUSY) {
2527 				qp = com->obufq.l_next;
2528 				while ((next = qp->l_next) != NULL)
2529 					qp = next;
2530 				qp->l_next = &com->obufs[1];
2531 			} else {
2532 				com->obufq.l_head = com->obufs[1].l_head;
2533 				com->obufq.l_tail = com->obufs[1].l_tail;
2534 				com->obufq.l_next = &com->obufs[1];
2535 				com->state |= CS_BUSY;
2536 			}
2537 			com_unlock();
2538 		}
2539 		tp->t_state |= TS_BUSY;
2540 	}
2541 	com_lock();
2542 	if (com->state >= (CS_BUSY | CS_TTGO))
2543 		siointr1(com);	/* fake interrupt to start output */
2544 	com_unlock();
2545 	ttwwakeup(tp);
2546 	crit_exit();
2547 }
2548 
2549 static void
2550 comstop(tp, rw)
2551 	struct tty	*tp;
2552 	int		rw;
2553 {
2554 	struct com_s	*com;
2555 
2556 	com = com_addr(DEV_TO_UNIT(tp->t_dev));
2557 	if (com == NULL || com->gone)
2558 		return;
2559 	com_lock();
2560 	if (rw & FWRITE) {
2561 		if (com->hasfifo)
2562 #ifdef COM_ESP
2563 		    /* XXX avoid h/w bug. */
2564 		    if (!com->esp)
2565 #endif
2566 			sio_setreg(com, com_fifo,
2567 				   FIFO_XMT_RST | com->fifo_image);
2568 		com->obufs[0].l_queued = FALSE;
2569 		com->obufs[1].l_queued = FALSE;
2570 		if (com->state & CS_ODONE)
2571 			com_events -= LOTS_OF_EVENTS;
2572 		com->state &= ~(CS_ODONE | CS_BUSY);
2573 		com->tp->t_state &= ~TS_BUSY;
2574 	}
2575 	if (rw & FREAD) {
2576 		if (com->hasfifo)
2577 #ifdef COM_ESP
2578 		    /* XXX avoid h/w bug. */
2579 		    if (!com->esp)
2580 #endif
2581 			sio_setreg(com, com_fifo,
2582 				   FIFO_RCV_RST | com->fifo_image);
2583 		com_events -= (com->iptr - com->ibuf);
2584 		com->iptr = com->ibuf;
2585 	}
2586 	com_unlock();
2587 	comstart(tp);
2588 }
2589 
2590 static int
2591 commctl(com, bits, how)
2592 	struct com_s	*com;
2593 	int		bits;
2594 	int		how;
2595 {
2596 	int	mcr;
2597 	int	msr;
2598 
2599 	if (how == DMGET) {
2600 		bits = TIOCM_LE;	/* XXX - always enabled while open */
2601 		mcr = com->mcr_image;
2602 		if (mcr & MCR_DTR)
2603 			bits |= TIOCM_DTR;
2604 		if (mcr & MCR_RTS)
2605 			bits |= TIOCM_RTS;
2606 		msr = com->prev_modem_status;
2607 		if (msr & MSR_CTS)
2608 			bits |= TIOCM_CTS;
2609 		if (msr & MSR_DCD)
2610 			bits |= TIOCM_CD;
2611 		if (msr & MSR_DSR)
2612 			bits |= TIOCM_DSR;
2613 		/*
2614 		 * XXX - MSR_RI is naturally volatile, and we make MSR_TERI
2615 		 * more volatile by reading the modem status a lot.  Perhaps
2616 		 * we should latch both bits until the status is read here.
2617 		 */
2618 		if (msr & (MSR_RI | MSR_TERI))
2619 			bits |= TIOCM_RI;
2620 		return (bits);
2621 	}
2622 	mcr = 0;
2623 	if (bits & TIOCM_DTR)
2624 		mcr |= MCR_DTR;
2625 	if (bits & TIOCM_RTS)
2626 		mcr |= MCR_RTS;
2627 	if (com->gone)
2628 		return(0);
2629 	com_lock();
2630 	switch (how) {
2631 	case DMSET:
2632 		outb(com->modem_ctl_port,
2633 		     com->mcr_image = mcr | (com->mcr_image & MCR_IENABLE));
2634 		break;
2635 	case DMBIS:
2636 		outb(com->modem_ctl_port, com->mcr_image |= mcr);
2637 		break;
2638 	case DMBIC:
2639 		outb(com->modem_ctl_port, com->mcr_image &= ~mcr);
2640 		break;
2641 	}
2642 	com_unlock();
2643 	return (0);
2644 }
2645 
2646 static void
2647 siosettimeout()
2648 {
2649 	struct com_s	*com;
2650 	bool_t		someopen;
2651 	int		unit;
2652 
2653 	/*
2654 	 * Set our timeout period to 1 second if no polled devices are open.
2655 	 * Otherwise set it to max(1/200, 1/hz).
2656 	 * Enable timeouts iff some device is open.
2657 	 */
2658 	callout_stop(&sio_timeout_handle);
2659 	sio_timeout = hz;
2660 	someopen = FALSE;
2661 	for (unit = 0; unit < sio_numunits; ++unit) {
2662 		com = com_addr(unit);
2663 		if (com != NULL && com->tp != NULL
2664 		    && com->tp->t_state & TS_ISOPEN && !com->gone) {
2665 			someopen = TRUE;
2666 			if (com->poll || com->poll_output) {
2667 				sio_timeout = hz > 200 ? hz / 200 : 1;
2668 				break;
2669 			}
2670 		}
2671 	}
2672 	if (someopen) {
2673 		sio_timeouts_until_log = hz / sio_timeout;
2674 		callout_reset(&sio_timeout_handle, sio_timeout,
2675 				comwakeup, NULL);
2676 	} else {
2677 		/* Flush error messages, if any. */
2678 		sio_timeouts_until_log = 1;
2679 		comwakeup((void *)NULL);
2680 		callout_stop(&sio_timeout_handle);
2681 	}
2682 }
2683 
2684 static void
2685 comwakeup(chan)
2686 	void	*chan;
2687 {
2688 	struct com_s	*com;
2689 	int		unit;
2690 
2691 	callout_reset(&sio_timeout_handle, sio_timeout, comwakeup, NULL);
2692 
2693 	/*
2694 	 * Recover from lost output interrupts.
2695 	 * Poll any lines that don't use interrupts.
2696 	 */
2697 	for (unit = 0; unit < sio_numunits; ++unit) {
2698 		com = com_addr(unit);
2699 		if (com != NULL && !com->gone
2700 		    && (com->state >= (CS_BUSY | CS_TTGO) || com->poll)) {
2701 			com_lock();
2702 			siointr1(com);
2703 			com_unlock();
2704 		}
2705 	}
2706 
2707 	/*
2708 	 * Check for and log errors, but not too often.
2709 	 */
2710 	if (--sio_timeouts_until_log > 0)
2711 		return;
2712 	sio_timeouts_until_log = hz / sio_timeout;
2713 	for (unit = 0; unit < sio_numunits; ++unit) {
2714 		int	errnum;
2715 
2716 		com = com_addr(unit);
2717 		if (com == NULL)
2718 			continue;
2719 		if (com->gone)
2720 			continue;
2721 		for (errnum = 0; errnum < CE_NTYPES; ++errnum) {
2722 			u_int	delta;
2723 			u_long	total;
2724 
2725 			com_lock();
2726 			delta = com->delta_error_counts[errnum];
2727 			com->delta_error_counts[errnum] = 0;
2728 			com_unlock();
2729 			if (delta == 0)
2730 				continue;
2731 			total = com->error_counts[errnum] += delta;
2732 			log(LOG_ERR, "sio%d: %u more %s%s (total %lu)\n",
2733 			    unit, delta, error_desc[errnum],
2734 			    delta == 1 ? "" : "s", total);
2735 		}
2736 	}
2737 }
2738 
2739 static void
2740 disc_optim(tp, t, com)
2741 	struct tty	*tp;
2742 	struct termios	*t;
2743 	struct com_s	*com;
2744 {
2745 	if (!(t->c_iflag & (ICRNL | IGNCR | IMAXBEL | INLCR | ISTRIP | IXON))
2746 	    && (!(t->c_iflag & BRKINT) || (t->c_iflag & IGNBRK))
2747 	    && (!(t->c_iflag & PARMRK)
2748 		|| (t->c_iflag & (IGNPAR | IGNBRK)) == (IGNPAR | IGNBRK))
2749 	    && !(t->c_lflag & (ECHO | ICANON | IEXTEN | ISIG | PENDIN))
2750 	    && linesw[tp->t_line].l_rint == ttyinput)
2751 		tp->t_state |= TS_CAN_BYPASS_L_RINT;
2752 	else
2753 		tp->t_state &= ~TS_CAN_BYPASS_L_RINT;
2754 	com->hotchar = linesw[tp->t_line].l_hotchar;
2755 }
2756 
2757 /*
2758  * Following are all routines needed for SIO to act as console
2759  */
2760 #include <sys/cons.h>
2761 
2762 struct siocnstate {
2763 	u_char	dlbl;
2764 	u_char	dlbh;
2765 	u_char	ier;
2766 	u_char	cfcr;
2767 	u_char	mcr;
2768 };
2769 
2770 static speed_t siocngetspeed (Port_t, u_long rclk);
2771 static void siocnclose	(struct siocnstate *sp, Port_t iobase);
2772 static void siocnopen	(struct siocnstate *sp, Port_t iobase, int speed);
2773 static void siocntxwait	(Port_t iobase);
2774 
2775 static cn_probe_t siocnprobe;
2776 static cn_init_t siocninit;
2777 static cn_checkc_t siocncheckc;
2778 static cn_getc_t siocngetc;
2779 static cn_putc_t siocnputc;
2780 
2781 #ifdef __i386__
2782 CONS_DRIVER(sio, siocnprobe, siocninit, NULL, siocngetc, siocncheckc,
2783 	    siocnputc, NULL);
2784 #endif
2785 
2786 /* To get the GDB related variables */
2787 #if DDB > 0
2788 #include <ddb/ddb.h>
2789 #endif
2790 
2791 static void
2792 siocntxwait(iobase)
2793 	Port_t	iobase;
2794 {
2795 	int	timo;
2796 
2797 	/*
2798 	 * Wait for any pending transmission to finish.  Required to avoid
2799 	 * the UART lockup bug when the speed is changed, and for normal
2800 	 * transmits.
2801 	 */
2802 	timo = 100000;
2803 	while ((inb(iobase + com_lsr) & (LSR_TSRE | LSR_TXRDY))
2804 	       != (LSR_TSRE | LSR_TXRDY) && --timo != 0)
2805 		;
2806 }
2807 
2808 /*
2809  * Read the serial port specified and try to figure out what speed
2810  * it's currently running at.  We're assuming the serial port has
2811  * been initialized and is basicly idle.  This routine is only intended
2812  * to be run at system startup.
2813  *
2814  * If the value read from the serial port doesn't make sense, return 0.
2815  */
2816 
2817 static speed_t
2818 siocngetspeed(iobase, rclk)
2819 	Port_t	iobase;
2820 	u_long	rclk;
2821 {
2822 	u_int	divisor;
2823 	u_char	dlbh;
2824 	u_char	dlbl;
2825 	u_char  cfcr;
2826 
2827 	cfcr = inb(iobase + com_cfcr);
2828 	outb(iobase + com_cfcr, CFCR_DLAB | cfcr);
2829 
2830 	dlbl = inb(iobase + com_dlbl);
2831 	dlbh = inb(iobase + com_dlbh);
2832 
2833 	outb(iobase + com_cfcr, cfcr);
2834 
2835 	divisor = dlbh << 8 | dlbl;
2836 
2837 	/* XXX there should be more sanity checking. */
2838 	if (divisor == 0)
2839 		return (CONSPEED);
2840 	return (rclk / (16UL * divisor));
2841 }
2842 
2843 static void
2844 siocnopen(sp, iobase, speed)
2845 	struct siocnstate	*sp;
2846 	Port_t			iobase;
2847 	int			speed;
2848 {
2849 	u_int	divisor;
2850 	u_char	dlbh;
2851 	u_char	dlbl;
2852 
2853 	/*
2854 	 * Save all the device control registers except the fifo register
2855 	 * and set our default ones (cs8 -parenb speed=comdefaultrate).
2856 	 * We can't save the fifo register since it is read-only.
2857 	 */
2858 	sp->ier = inb(iobase + com_ier);
2859 	outb(iobase + com_ier, 0);	/* spltty() doesn't stop siointr() */
2860 	siocntxwait(iobase);
2861 	sp->cfcr = inb(iobase + com_cfcr);
2862 	outb(iobase + com_cfcr, CFCR_DLAB | CFCR_8BITS);
2863 	sp->dlbl = inb(iobase + com_dlbl);
2864 	sp->dlbh = inb(iobase + com_dlbh);
2865 	/*
2866 	 * Only set the divisor registers if they would change, since on
2867 	 * some 16550 incompatibles (Startech), setting them clears the
2868 	 * data input register.  This also reduces the effects of the
2869 	 * UMC8669F bug.
2870 	 */
2871 	divisor = siodivisor(comdefaultrclk, speed);
2872 	dlbl = divisor & 0xFF;
2873 	if (sp->dlbl != dlbl)
2874 		outb(iobase + com_dlbl, dlbl);
2875 	dlbh = divisor >> 8;
2876 	if (sp->dlbh != dlbh)
2877 		outb(iobase + com_dlbh, dlbh);
2878 	outb(iobase + com_cfcr, CFCR_8BITS);
2879 	sp->mcr = inb(iobase + com_mcr);
2880 	/*
2881 	 * We don't want interrupts, but must be careful not to "disable"
2882 	 * them by clearing the MCR_IENABLE bit, since that might cause
2883 	 * an interrupt by floating the IRQ line.
2884 	 */
2885 	outb(iobase + com_mcr, (sp->mcr & MCR_IENABLE) | MCR_DTR | MCR_RTS);
2886 }
2887 
2888 static void
2889 siocnclose(sp, iobase)
2890 	struct siocnstate	*sp;
2891 	Port_t			iobase;
2892 {
2893 	/*
2894 	 * Restore the device control registers.
2895 	 */
2896 	siocntxwait(iobase);
2897 	outb(iobase + com_cfcr, CFCR_DLAB | CFCR_8BITS);
2898 	if (sp->dlbl != inb(iobase + com_dlbl))
2899 		outb(iobase + com_dlbl, sp->dlbl);
2900 	if (sp->dlbh != inb(iobase + com_dlbh))
2901 		outb(iobase + com_dlbh, sp->dlbh);
2902 	outb(iobase + com_cfcr, sp->cfcr);
2903 	/*
2904 	 * XXX damp oscillations of MCR_DTR and MCR_RTS by not restoring them.
2905 	 */
2906 	outb(iobase + com_mcr, sp->mcr | MCR_DTR | MCR_RTS);
2907 	outb(iobase + com_ier, sp->ier);
2908 }
2909 
2910 static void
2911 siocnprobe(cp)
2912 	struct consdev	*cp;
2913 {
2914 	speed_t			boot_speed;
2915 	u_char			cfcr;
2916 	u_int			divisor;
2917 	int			unit;
2918 	struct siocnstate	sp;
2919 
2920 	/*
2921 	 * Find our first enabled console, if any.  If it is a high-level
2922 	 * console device, then initialize it and return successfully.
2923 	 * If it is a low-level console device, then initialize it and
2924 	 * return unsuccessfully.  It must be initialized in both cases
2925 	 * for early use by console drivers and debuggers.  Initializing
2926 	 * the hardware is not necessary in all cases, since the i/o
2927 	 * routines initialize it on the fly, but it is necessary if
2928 	 * input might arrive while the hardware is switched back to an
2929 	 * uninitialized state.  We can't handle multiple console devices
2930 	 * yet because our low-level routines don't take a device arg.
2931 	 * We trust the user to set the console flags properly so that we
2932 	 * don't need to probe.
2933 	 */
2934 	cp->cn_pri = CN_DEAD;
2935 
2936 	for (unit = 0; unit < 16; unit++) { /* XXX need to know how many */
2937 		int flags;
2938 		int disabled;
2939 		if (resource_int_value("sio", unit, "disabled", &disabled) == 0) {
2940 			if (disabled)
2941 				continue;
2942 		}
2943 		if (resource_int_value("sio", unit, "flags", &flags))
2944 			continue;
2945 		if (COM_CONSOLE(flags) || COM_DEBUGGER(flags)) {
2946 			int port;
2947 			Port_t iobase;
2948 
2949 			if (resource_int_value("sio", unit, "port", &port))
2950 				continue;
2951 			iobase = port;
2952 			crit_enter();
2953 			if (boothowto & RB_SERIAL) {
2954 				boot_speed =
2955 				    siocngetspeed(iobase, comdefaultrclk);
2956 				if (boot_speed)
2957 					comdefaultrate = boot_speed;
2958 			}
2959 
2960 			/*
2961 			 * Initialize the divisor latch.  We can't rely on
2962 			 * siocnopen() to do this the first time, since it
2963 			 * avoids writing to the latch if the latch appears
2964 			 * to have the correct value.  Also, if we didn't
2965 			 * just read the speed from the hardware, then we
2966 			 * need to set the speed in hardware so that
2967 			 * switching it later is null.
2968 			 */
2969 			cfcr = inb(iobase + com_cfcr);
2970 			outb(iobase + com_cfcr, CFCR_DLAB | cfcr);
2971 			divisor = siodivisor(comdefaultrclk, comdefaultrate);
2972 			outb(iobase + com_dlbl, divisor & 0xff);
2973 			outb(iobase + com_dlbh, divisor >> 8);
2974 			outb(iobase + com_cfcr, cfcr);
2975 
2976 			siocnopen(&sp, iobase, comdefaultrate);
2977 
2978 			crit_exit();
2979 			if (COM_CONSOLE(flags) && !COM_LLCONSOLE(flags)) {
2980 				cp->cn_dev = make_dev(&sio_cdevsw, unit,
2981 						UID_ROOT, GID_WHEEL, 0600,
2982 						"ttyd%r", unit);
2983 				cp->cn_pri = COM_FORCECONSOLE(flags)
2984 					     || boothowto & RB_SERIAL
2985 					     ? CN_REMOTE : CN_NORMAL;
2986 				siocniobase = iobase;
2987 				siocnunit = unit;
2988 			}
2989 			if (COM_DEBUGGER(flags)) {
2990 				printf("sio%d: gdb debugging port\n", unit);
2991 				siogdbiobase = iobase;
2992 				siogdbunit = unit;
2993 #if DDB > 0
2994 				gdbdev = make_dev(&sio_cdevsw, unit,
2995 						UID_ROOT, GID_WHEEL, 0600,
2996 						"ttyd%r", unit);
2997 				gdb_getc = siocngetc;
2998 				gdb_putc = siocnputc;
2999 #endif
3000 			}
3001 		}
3002 	}
3003 #ifdef	__i386__
3004 #if DDB > 0
3005 	/*
3006 	 * XXX Ugly Compatability.
3007 	 * If no gdb port has been specified, set it to be the console
3008 	 * as some configuration files don't specify the gdb port.
3009 	 */
3010 	if (gdbdev == NODEV && (boothowto & RB_GDB)) {
3011 		printf("Warning: no GDB port specified. Defaulting to sio%d.\n",
3012 			siocnunit);
3013 		printf("Set flag 0x80 on desired GDB port in your\n");
3014 		printf("configuration file (currently sio only).\n");
3015 		siogdbiobase = siocniobase;
3016 		siogdbunit = siocnunit;
3017 		gdbdev = make_dev(&sio_cdevsw, siocnunit,
3018 				UID_ROOT, GID_WHEEL, 0600,
3019 				"ttyd%r", siocnunit);
3020 		gdb_getc = siocngetc;
3021 		gdb_putc = siocnputc;
3022 	}
3023 #endif
3024 #endif
3025 }
3026 
3027 static void
3028 siocninit(cp)
3029 	struct consdev	*cp;
3030 {
3031 	comconsole = DEV_TO_UNIT(cp->cn_dev);
3032 }
3033 
3034 static int
3035 siocncheckc(dev)
3036 	dev_t	dev;
3037 {
3038 	int	c;
3039 	Port_t	iobase;
3040 	struct siocnstate	sp;
3041 
3042 	if (minor(dev) == siogdbunit)
3043 		iobase = siogdbiobase;
3044 	else
3045 		iobase = siocniobase;
3046 	crit_enter();
3047 	siocnopen(&sp, iobase, comdefaultrate);
3048 	if (inb(iobase + com_lsr) & LSR_RXRDY)
3049 		c = inb(iobase + com_data);
3050 	else
3051 		c = -1;
3052 	siocnclose(&sp, iobase);
3053 	crit_exit();
3054 	return (c);
3055 }
3056 
3057 
3058 int
3059 siocngetc(dev)
3060 	dev_t	dev;
3061 {
3062 	int	c;
3063 	Port_t	iobase;
3064 	struct siocnstate	sp;
3065 
3066 	if (minor(dev) == siogdbunit)
3067 		iobase = siogdbiobase;
3068 	else
3069 		iobase = siocniobase;
3070 	crit_enter();
3071 	siocnopen(&sp, iobase, comdefaultrate);
3072 	while (!(inb(iobase + com_lsr) & LSR_RXRDY))
3073 		;
3074 	c = inb(iobase + com_data);
3075 	siocnclose(&sp, iobase);
3076 	crit_exit();
3077 	return (c);
3078 }
3079 
3080 void
3081 siocnputc(dev, c)
3082 	dev_t	dev;
3083 	int	c;
3084 {
3085 	struct siocnstate	sp;
3086 	Port_t	iobase;
3087 
3088 	if (minor(dev) == siogdbunit)
3089 		iobase = siogdbiobase;
3090 	else
3091 		iobase = siocniobase;
3092 	crit_enter();
3093 	siocnopen(&sp, iobase, comdefaultrate);
3094 	siocntxwait(iobase);
3095 	outb(iobase + com_data, c);
3096 	siocnclose(&sp, iobase);
3097 	crit_exit();
3098 }
3099 
3100 DRIVER_MODULE(sio, isa, sio_isa_driver, sio_devclass, 0, 0);
3101 #if NPCI > 0
3102 DRIVER_MODULE(sio, pci, sio_pci_driver, sio_devclass, 0, 0);
3103 #endif
3104 #if NPUC > 0
3105 DRIVER_MODULE(sio, puc, sio_puc_driver, sio_devclass, 0, 0);
3106 #endif
3107