xref: /dflybsd-src/sys/dev/serial/sio/sio.c (revision 1f7ab7c9fc18f47a2f16dc45b13dee254c603ce7)
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 1.36 2006/10/25 20:56:02 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 <sys/rman.h>
74 #include <sys/timepps.h>
75 #include <sys/thread2.h>
76 
77 #include <machine/limits.h>
78 
79 #include <bus/isa/isareg.h>
80 #include <bus/isa/isavar.h>
81 #if NPCI > 0
82 #include <bus/pci/pcireg.h>
83 #include <bus/pci/pcivar.h>
84 #endif
85 #if NPUC > 0
86 #include <dev/misc/puc/pucvar.h>
87 #endif
88 #include <machine/lock.h>
89 
90 #include <machine/clock.h>
91 #include <machine/ipl.h>
92 #ifndef SMP
93 #include <machine/lock.h>
94 #endif
95 
96 #include "sioreg.h"
97 #include "sio_private.h"
98 
99 #ifdef COM_ESP
100 #include "../ic_layer/esp.h"
101 #endif
102 
103 #define	LOTS_OF_EVENTS	64	/* helps separate urgent events from input */
104 
105 #define	CALLOUT_MASK		0x80
106 #define	CONTROL_MASK		0x60
107 #define	CONTROL_INIT_STATE	0x20
108 #define	CONTROL_LOCK_STATE	0x40
109 #define	DEV_TO_UNIT(dev)	(MINOR_TO_UNIT(minor(dev)))
110 #define	MINOR_TO_UNIT(mynor)	((((mynor) & ~0xffffU) >> (8 + 3)) \
111 				 | ((mynor) & 0x1f))
112 #define	UNIT_TO_MINOR(unit)	((((unit) & ~0x1fU) << (8 + 3)) \
113 				 | ((unit) & 0x1f))
114 
115 #define	com_scr		7	/* scratch register for 16450-16550 (R/W) */
116 
117 #define	sio_getreg(com, off) \
118 	(bus_space_read_1((com)->bst, (com)->bsh, (off)))
119 #define	sio_setreg(com, off, value) \
120 	(bus_space_write_1((com)->bst, (com)->bsh, (off), (value)))
121 
122 /*
123  * com state bits.
124  * (CS_BUSY | CS_TTGO) and (CS_BUSY | CS_TTGO | CS_ODEVREADY) must be higher
125  * than the other bits so that they can be tested as a group without masking
126  * off the low bits.
127  *
128  * The following com and tty flags correspond closely:
129  *	CS_BUSY		= TS_BUSY (maintained by comstart(), siopoll() and
130  *				   comstop())
131  *	CS_TTGO		= ~TS_TTSTOP (maintained by comparam() and comstart())
132  *	CS_CTS_OFLOW	= CCTS_OFLOW (maintained by comparam())
133  *	CS_RTS_IFLOW	= CRTS_IFLOW (maintained by comparam())
134  * TS_FLUSH is not used.
135  * XXX I think TIOCSETA doesn't clear TS_TTSTOP when it clears IXON.
136  * XXX CS_*FLOW should be CF_*FLOW in com->flags (control flags not state).
137  */
138 #define	CS_BUSY		0x80	/* output in progress */
139 #define	CS_TTGO		0x40	/* output not stopped by XOFF */
140 #define	CS_ODEVREADY	0x20	/* external device h/w ready (CTS) */
141 #define	CS_CHECKMSR	1	/* check of MSR scheduled */
142 #define	CS_CTS_OFLOW	2	/* use CTS output flow control */
143 #define	CS_DTR_OFF	0x10	/* DTR held off */
144 #define	CS_ODONE	4	/* output completed */
145 #define	CS_RTS_IFLOW	8	/* use RTS input flow control */
146 #define	CSE_BUSYCHECK	1	/* siobusycheck() scheduled */
147 
148 static	char const * const	error_desc[] = {
149 #define	CE_OVERRUN			0
150 	"silo overflow",
151 #define	CE_INTERRUPT_BUF_OVERFLOW	1
152 	"interrupt-level buffer overflow",
153 #define	CE_TTY_BUF_OVERFLOW		2
154 	"tty-level buffer overflow",
155 };
156 
157 #ifdef COM_ESP
158 static	int	espattach	(struct com_s *com, Port_t esp_port);
159 #endif
160 static	int	sio_isa_attach	(device_t dev);
161 
162 static	timeout_t siobusycheck;
163 static	u_int	siodivisor	(u_long rclk, speed_t speed);
164 static	timeout_t siodtrwakeup;
165 static	void	comhardclose	(struct com_s *com);
166 static	void	sioinput	(struct com_s *com);
167 static	void	siointr1	(struct com_s *com);
168 static	void	siointr		(void *arg);
169 static	int	commctl		(struct com_s *com, int bits, int how);
170 static	int	comparam	(struct tty *tp, struct termios *t);
171 static	inthand2_t siopoll;
172 static	int	sio_isa_probe	(device_t dev);
173 static	void	siosettimeout	(void);
174 static	int	siosetwater	(struct com_s *com, speed_t speed);
175 static	void	comstart	(struct tty *tp);
176 static	void	comstop		(struct tty *tp, int rw);
177 static	timeout_t comwakeup;
178 static	void	disc_optim	(struct tty	*tp, struct termios *t,
179 				     struct com_s *com);
180 
181 #if NPCI > 0
182 static	int	sio_pci_attach (device_t dev);
183 static	void	sio_pci_kludge_unit (device_t dev);
184 static	int	sio_pci_probe (device_t dev);
185 #endif /* NPCI > 0 */
186 
187 #if NPUC > 0
188 static	int	sio_puc_attach (device_t dev);
189 static	int	sio_puc_probe (device_t dev);
190 #endif /* NPUC > 0 */
191 
192 static char driver_name[] = "sio";
193 
194 /* table and macro for fast conversion from a unit number to its com struct */
195 devclass_t	sio_devclass;
196 #define	com_addr(unit)	((struct com_s *) \
197 			 devclass_get_softc(sio_devclass, unit))
198 
199 static device_method_t sio_isa_methods[] = {
200 	/* Device interface */
201 	DEVMETHOD(device_probe,		sio_isa_probe),
202 	DEVMETHOD(device_attach,	sio_isa_attach),
203 
204 	{ 0, 0 }
205 };
206 
207 static driver_t sio_isa_driver = {
208 	driver_name,
209 	sio_isa_methods,
210 	sizeof(struct com_s),
211 };
212 
213 #if NPCI > 0
214 static device_method_t sio_pci_methods[] = {
215 	/* Device interface */
216 	DEVMETHOD(device_probe,		sio_pci_probe),
217 	DEVMETHOD(device_attach,	sio_pci_attach),
218 
219 	{ 0, 0 }
220 };
221 
222 static driver_t sio_pci_driver = {
223 	driver_name,
224 	sio_pci_methods,
225 	sizeof(struct com_s),
226 };
227 #endif /* NPCI > 0 */
228 
229 #if NPUC > 0
230 static device_method_t sio_puc_methods[] = {
231 	/* Device interface */
232 	DEVMETHOD(device_probe,		sio_puc_probe),
233 	DEVMETHOD(device_attach,	sio_puc_attach),
234 
235 	{ 0, 0 }
236 };
237 
238 static driver_t sio_puc_driver = {
239 	driver_name,
240 	sio_puc_methods,
241 	sizeof(struct com_s),
242 };
243 #endif /* NPUC > 0 */
244 
245 static	d_open_t	sioopen;
246 static	d_close_t	sioclose;
247 static	d_read_t	sioread;
248 static	d_write_t	siowrite;
249 static	d_ioctl_t	sioioctl;
250 
251 #define	CDEV_MAJOR	28
252 static struct dev_ops sio_ops = {
253 	{ driver_name, CDEV_MAJOR, D_TTY | D_KQFILTER },
254 	.d_open =	sioopen,
255 	.d_close =	sioclose,
256 	.d_read =	sioread,
257 	.d_write =	siowrite,
258 	.d_ioctl =	sioioctl,
259 	.d_poll =	ttypoll,
260 	.d_kqfilter =	ttykqfilter
261 };
262 
263 int	comconsole = -1;
264 static	volatile speed_t	comdefaultrate = CONSPEED;
265 static	u_long			comdefaultrclk = DEFAULT_RCLK;
266 SYSCTL_ULONG(_machdep, OID_AUTO, conrclk, CTLFLAG_RW, &comdefaultrclk, 0, "");
267 static	u_int	com_events;	/* input chars + weighted output completions */
268 static	Port_t	siocniobase;
269 static	int	siocnunit;
270 static	Port_t	siogdbiobase;
271 static	int	siogdbunit = -1;
272 static	bool_t	sio_registered;
273 static	int	sio_timeout;
274 static	int	sio_timeouts_until_log;
275 static	struct	callout	sio_timeout_handle;
276 static	int	sio_numunits;
277 
278 #ifdef COM_ESP
279 /* XXX configure this properly. */
280 static	Port_t	likely_com_ports[] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8, };
281 static	Port_t	likely_esp_ports[] = { 0x140, 0x180, 0x280, 0 };
282 #endif
283 
284 /*
285  * handle sysctl read/write requests for console speed
286  *
287  * In addition to setting comdefaultrate for I/O through /dev/console,
288  * also set the initial and lock values for the /dev/ttyXX device
289  * if there is one associated with the console.  Finally, if the /dev/tty
290  * device has already been open, change the speed on the open running port
291  * itself.
292  */
293 
294 static int
295 sysctl_machdep_comdefaultrate(SYSCTL_HANDLER_ARGS)
296 {
297 	int error;
298 	speed_t newspeed;
299 	struct com_s *com;
300 	struct tty *tp;
301 
302 	newspeed = comdefaultrate;
303 
304 	error = sysctl_handle_opaque(oidp, &newspeed, sizeof newspeed, req);
305 	if (error || !req->newptr)
306 		return (error);
307 
308 	comdefaultrate = newspeed;
309 
310 	if (comconsole < 0)		/* serial console not selected? */
311 		return (0);
312 
313 	com = com_addr(comconsole);
314 	if (com == NULL)
315 		return (ENXIO);
316 
317 	/*
318 	 * set the initial and lock rates for /dev/ttydXX and /dev/cuaXX
319 	 * (note, the lock rates really are boolean -- if non-zero, disallow
320 	 *  speed changes)
321 	 */
322 	com->it_in.c_ispeed  = com->it_in.c_ospeed =
323 	com->lt_in.c_ispeed  = com->lt_in.c_ospeed =
324 	com->it_out.c_ispeed = com->it_out.c_ospeed =
325 	com->lt_out.c_ispeed = com->lt_out.c_ospeed = comdefaultrate;
326 
327 	/*
328 	 * if we're open, change the running rate too
329 	 */
330 	tp = com->tp;
331 	if (tp && (tp->t_state & TS_ISOPEN)) {
332 		tp->t_termios.c_ispeed =
333 		tp->t_termios.c_ospeed = comdefaultrate;
334 		crit_enter();
335 		error = comparam(tp, &tp->t_termios);
336 		crit_exit();
337 	}
338 	return error;
339 }
340 
341 SYSCTL_PROC(_machdep, OID_AUTO, conspeed, CTLTYPE_INT | CTLFLAG_RW,
342 	    0, 0, sysctl_machdep_comdefaultrate, "I", "");
343 
344 #if NPCI > 0
345 struct pci_ids {
346 	u_int32_t	type;
347 	const char	*desc;
348 	int		rid;
349 };
350 
351 static struct pci_ids pci_ids[] = {
352 	{ 0x100812b9, "3COM PCI FaxModem", 0x10 },
353 	{ 0x2000131f, "CyberSerial (1-port) 16550", 0x10 },
354 	{ 0x01101407, "Koutech IOFLEX-2S PCI Dual Port Serial", 0x10 },
355 	{ 0x01111407, "Koutech IOFLEX-2S PCI Dual Port Serial", 0x10 },
356 	{ 0x048011c1, "Lucent kermit based PCI Modem", 0x14 },
357 	{ 0x95211415, "Oxford Semiconductor PCI Dual Port Serial", 0x10 },
358 	{ 0x7101135e, "SeaLevel Ultra 530.PCI Single Port Serial", 0x18 },
359 	{ 0x0000151f, "SmartLink 5634PCV SurfRider", 0x10 },
360 	{ 0x98459710, "Netmos Nm9845 PCI Bridge with Dual UART", 0x10 },
361 	{ 0x00000000, NULL, 0 }
362 };
363 
364 static int
365 sio_pci_attach(dev)
366 	device_t	dev;
367 {
368 	u_int32_t	type;
369 	struct pci_ids	*id;
370 
371 	type = pci_get_devid(dev);
372 	id = pci_ids;
373 	while (id->type && id->type != type)
374 		id++;
375 	if (id->desc == NULL)
376 		return (ENXIO);
377 	sio_pci_kludge_unit(dev);
378 	return (sioattach(dev, id->rid, 0UL));
379 }
380 
381 /*
382  * Don't cut and paste this to other drivers.  It is a horrible kludge
383  * which will fail to work and also be unnecessary in future versions.
384  */
385 static void
386 sio_pci_kludge_unit(dev)
387 	device_t dev;
388 {
389 	devclass_t	dc;
390 	int		err;
391 	int		start;
392 	int		unit;
393 
394 	unit = 0;
395 	start = 0;
396 	while (resource_int_value("sio", unit, "port", &start) == 0 &&
397 	    start > 0)
398 		unit++;
399 	if (device_get_unit(dev) < unit) {
400 		dc = device_get_devclass(dev);
401 		while (devclass_get_device(dc, unit))
402 			unit++;
403 		device_printf(dev, "moving to sio%d\n", unit);
404 		err = device_set_unit(dev, unit);	/* EVIL DO NOT COPY */
405 		if (err)
406 			device_printf(dev, "error moving device %d\n", err);
407 	}
408 }
409 
410 static int
411 sio_pci_probe(dev)
412 	device_t	dev;
413 {
414 	u_int32_t	type;
415 	struct pci_ids	*id;
416 
417 	type = pci_get_devid(dev);
418 	id = pci_ids;
419 	while (id->type && id->type != type)
420 		id++;
421 	if (id->desc == NULL)
422 		return (ENXIO);
423 	device_set_desc(dev, id->desc);
424 	return (sioprobe(dev, id->rid, 0UL));
425 }
426 #endif /* NPCI > 0 */
427 
428 #if NPUC > 0
429 static int
430 sio_puc_attach(dev)
431 	device_t	dev;
432 {
433 	u_int rclk;
434 
435 	if (BUS_READ_IVAR(device_get_parent(dev), dev, PUC_IVAR_FREQ,
436 	    &rclk) != 0)
437 		rclk = DEFAULT_RCLK;
438 	return (sioattach(dev, 0, rclk));
439 }
440 
441 static int
442 sio_puc_probe(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 (sioprobe(dev, 0, rclk));
451 }
452 #endif /* NPUC */
453 
454 static struct isa_pnp_id sio_ids[] = {
455 	{0x0005d041, "Standard PC COM port"},	/* PNP0500 */
456 	{0x0105d041, "16550A-compatible COM port"},	/* PNP0501 */
457 	{0x0205d041, "Multiport serial device (non-intelligent 16550)"}, /* PNP0502 */
458 	{0x1005d041, "Generic IRDA-compatible device"},	/* PNP0510 */
459 	{0x1105d041, "Generic IRDA-compatible device"},	/* PNP0511 */
460 	/* Devices that do not have a compatid */
461 	{0x12206804, NULL},     /* ACH2012 - 5634BTS 56K Video Ready Modem */
462 	{0x7602a904, NULL},	/* AEI0276 - 56K v.90 Fax Modem (LKT) */
463 	{0x00007905, NULL},	/* AKY0000 - 56K Plug&Play Modem */
464 	{0x21107905, NULL},	/* AKY1021 - 56K Plug&Play Modem */
465 	{0x01405407, NULL},	/* AZT4001 - AZT3000 PnP SOUND DEVICE, MODEM */
466 	{0x56039008, NULL},	/* BDP0356 - Best Data 56x2 */
467 	{0x56159008, NULL},	/* BDP1556 - B.D. Smart One 56SPS,Voice Modem*/
468 	{0x36339008, NULL},	/* BDP3336 - Best Data Prods. 336F */
469 	{0x0014490a, NULL},	/* BRI1400 - Boca 33.6 PnP */
470 	{0x0015490a, NULL},	/* BRI1500 - Internal Fax Data */
471 	{0x0034490a, NULL},	/* BRI3400 - Internal ACF Modem */
472 	{0x0094490a, NULL},	/* BRI9400 - Boca K56Flex PnP */
473 	{0x00b4490a, NULL},	/* BRIB400 - Boca 56k PnP */
474 	{0x0030320d, NULL},	/* CIR3000 - Cirrus Logic V43 */
475 	{0x0100440e, NULL},	/* CRD0001 - Cardinal MVP288IV ? */
476 	{0x01308c0e, NULL},	/* CTL3001 - Creative Labs Phoneblaster */
477 	{0x36033610, NULL},     /* DAV0336 - DAVICOM 336PNP MODEM */
478 	{0x01009416, NULL},     /* ETT0001 - E-Tech Bullet 33k6 PnP */
479 	{0x0000aa1a, NULL},	/* FUJ0000 - FUJITSU Modem 33600 PNP/I2 */
480 	{0x1200c31e, NULL},	/* GVC0012 - VF1128HV-R9 (win modem?) */
481 	{0x0303c31e, NULL},	/* GVC0303 - MaxTech 33.6 PnP D/F/V */
482 	{0x0505c31e, NULL},	/* GVC0505 - GVC 56k Faxmodem */
483 	{0x0116c31e, NULL},	/* GVC1601 - Rockwell V.34 Plug & Play Modem */
484 	{0x0050c31e, NULL},	/* GVC5000 - some GVC modem */
485 	{0x3800f91e, NULL},	/* GWY0038 - Telepath with v.90 */
486 	{0x9062f91e, NULL},	/* GWY6290 - Telepath with x2 Technology */
487 	{0x8100e425, NULL},	/* IOD0081 - I-O DATA DEVICE,INC. IFML-560 */
488 	{0x21002534, NULL},	/* MAE0021 - Jetstream Int V.90 56k Voice Series 2*/
489 	{0x0000f435, NULL},	/* MOT0000 - Motorola ModemSURFR 33.6 Intern */
490 	{0x5015f435, NULL},	/* MOT1550 - Motorola ModemSURFR 56K Modem */
491 	{0xf015f435, NULL},	/* MOT15F0 - Motorola VoiceSURFR 56K Modem */
492 	{0x6045f435, NULL},	/* MOT4560 - Motorola ? */
493 	{0x61e7a338, NULL},	/* NECE761 - 33.6Modem */
494  	{0x08804f3f, NULL},	/* OZO8008 - Zoom  (33.6k Modem) */
495 	{0x0f804f3f, NULL},	/* OZO800f - Zoom 2812 (56k Modem) */
496 	{0x39804f3f, NULL},	/* OZO8039 - Zoom 56k flex */
497 	{0x00914f3f, NULL},	/* OZO9100 - Zoom 2919 (K56 Faxmodem) */
498 	{0x3024a341, NULL},	/* PMC2430 - Pace 56 Voice Internal Modem */
499 	{0x1000eb49, NULL},	/* ROK0010 - Rockwell ? */
500 	{0x1200b23d, NULL},     /* RSS0012 - OMRON ME5614ISA */
501 	{0x5002734a, NULL},	/* RSS0250 - 5614Jx3(G) Internal Modem */
502 	{0x6202734a, NULL},	/* RSS0262 - 5614Jx3[G] V90+K56Flex Modem */
503 	{0x1010104d, NULL},	/* SHP1010 - Rockwell 33600bps Modem */
504 	{0xc100ad4d, NULL},	/* SMM00C1 - Leopard 56k PnP */
505 	{0x9012b04e, NULL},	/* SUP1290 - Supra ? */
506 	{0x1013b04e, NULL},	/* SUP1310 - SupraExpress 336i PnP */
507 	{0x8013b04e, NULL},	/* SUP1380 - SupraExpress 288i PnP Voice */
508 	{0x8113b04e, NULL},	/* SUP1381 - SupraExpress 336i PnP Voice */
509 	{0x5016b04e, NULL},	/* SUP1650 - Supra 336i Sp Intl */
510 	{0x7016b04e, NULL},	/* SUP1670 - Supra 336i V+ Intl */
511 	{0x7420b04e, NULL},	/* SUP2070 - Supra ? */
512 	{0x8020b04e, NULL},	/* SUP2080 - Supra ? */
513 	{0x8420b04e, NULL},	/* SUP2084 - SupraExpress 56i PnP */
514 	{0x7121b04e, NULL},	/* SUP2171 - SupraExpress 56i Sp? */
515 	{0x8024b04e, NULL},	/* SUP2480 - Supra ? */
516 	{0x01007256, NULL},	/* USR0001 - U.S. Robotics Inc., Sportster W */
517 	{0x02007256, NULL},	/* USR0002 - U.S. Robotics Inc. Sportster 33. */
518 	{0x04007256, NULL},	/* USR0004 - USR Sportster 14.4k */
519 	{0x06007256, NULL},	/* USR0006 - USR Sportster 33.6k */
520 	{0x11007256, NULL},	/* USR0011 - USR ? */
521 	{0x01017256, NULL},	/* USR0101 - USR ? */
522 	{0x30207256, NULL},	/* USR2030 - U.S.Robotics Inc. Sportster 560 */
523 	{0x50207256, NULL},	/* USR2050 - U.S.Robotics Inc. Sportster 33. */
524 	{0x70207256, NULL},	/* USR2070 - U.S.Robotics Inc. Sportster 560 */
525 	{0x30307256, NULL},	/* USR3030 - U.S. Robotics 56K FAX INT */
526 	{0x31307256, NULL},	/* USR3031 - U.S. Robotics 56K FAX INT */
527 	{0x50307256, NULL},	/* USR3050 - U.S. Robotics 56K FAX INT */
528 	{0x70307256, NULL},	/* USR3070 - U.S. Robotics 56K Voice INT */
529 	{0x90307256, NULL},	/* USR3090 - USR ? */
530 	{0x70917256, NULL},	/* USR9170 - U.S. Robotics 56K FAX INT */
531 	{0x90917256, NULL},	/* USR9190 - USR 56k Voice INT */
532 	{0x0300695c, NULL},	/* WCI0003 - Fax/Voice/Modem/Speakphone/Asvd */
533 	{0x01a0896a, NULL},	/* ZTIA001 - Zoom Internal V90 Faxmodem */
534 	{0x61f7896a, NULL},	/* ZTIF761 - Zoom ComStar 33.6 */
535 	{0}
536 };
537 
538 
539 
540 static int
541 sio_isa_probe(dev)
542 	device_t	dev;
543 {
544 	/* Check isapnp ids */
545 	if (ISA_PNP_PROBE(device_get_parent(dev), dev, sio_ids) == ENXIO)
546 		return (ENXIO);
547 	return (sioprobe(dev, 0, 0UL));
548 }
549 
550 int
551 sioprobe(dev, xrid, rclk)
552 	device_t	dev;
553 	int		xrid;
554 	u_long		rclk;
555 {
556 #if 0
557 	static bool_t	already_init;
558 	device_t	xdev;
559 #endif
560 	struct com_s	*com;
561 	u_int		divisor;
562 	bool_t		failures[10];
563 	int		fn;
564 	device_t	idev;
565 	Port_t		iobase;
566 	intrmask_t	irqmap[4];
567 	intrmask_t	irqs;
568 	u_char		mcr_image;
569 	int		result;
570 	u_long		xirq;
571 	u_int		flags = device_get_flags(dev);
572 	int		rid;
573 	struct resource *port;
574 
575 	rid = xrid;
576 	port = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid,
577 				  0, ~0, IO_COMSIZE, RF_ACTIVE);
578 	if (!port)
579 		return (ENXIO);
580 
581 	com = device_get_softc(dev);
582 	com->bst = rman_get_bustag(port);
583 	com->bsh = rman_get_bushandle(port);
584 	if (rclk == 0)
585 		rclk = DEFAULT_RCLK;
586 	com->rclk = rclk;
587 
588 #if 0
589 	/*
590 	 * XXX this is broken - when we are first called, there are no
591 	 * previously configured IO ports.  We could hard code
592 	 * 0x3f8, 0x2f8, 0x3e8, 0x2e8 etc but that's probably worse.
593 	 * This code has been doing nothing since the conversion since
594 	 * "count" is zero the first time around.
595 	 */
596 	if (!already_init) {
597 		/*
598 		 * Turn off MCR_IENABLE for all likely serial ports.  An unused
599 		 * port with its MCR_IENABLE gate open will inhibit interrupts
600 		 * from any used port that shares the interrupt vector.
601 		 * XXX the gate enable is elsewhere for some multiports.
602 		 */
603 		device_t *devs;
604 		int count, i, xioport;
605 
606 		devclass_get_devices(sio_devclass, &devs, &count);
607 		for (i = 0; i < count; i++) {
608 			xdev = devs[i];
609 			if (device_is_enabled(xdev) &&
610 			    bus_get_resource(xdev, SYS_RES_IOPORT, 0, &xioport,
611 					     NULL) == 0)
612 				outb(xioport + com_mcr, 0);
613 		}
614 		kfree(devs, M_TEMP);
615 		already_init = TRUE;
616 	}
617 #endif
618 
619 	if (COM_LLCONSOLE(flags)) {
620 		printf("sio%d: reserved for low-level i/o\n",
621 		       device_get_unit(dev));
622 		bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
623 		return (ENXIO);
624 	}
625 
626 	/*
627 	 * If the device is on a multiport card and has an AST/4
628 	 * compatible interrupt control register, initialize this
629 	 * register and prepare to leave MCR_IENABLE clear in the mcr.
630 	 * Otherwise, prepare to set MCR_IENABLE in the mcr.
631 	 * Point idev to the device struct giving the correct id_irq.
632 	 * This is the struct for the master device if there is one.
633 	 */
634 	idev = dev;
635 	mcr_image = MCR_IENABLE;
636 #ifdef COM_MULTIPORT
637 	if (COM_ISMULTIPORT(flags)) {
638 		Port_t xiobase;
639 		u_long io;
640 
641 		idev = devclass_get_device(sio_devclass, COM_MPMASTER(flags));
642 		if (idev == NULL) {
643 			printf("sio%d: master device %d not configured\n",
644 			       device_get_unit(dev), COM_MPMASTER(flags));
645 			idev = dev;
646 		}
647 		if (!COM_NOTAST4(flags)) {
648 			if (bus_get_resource(idev, SYS_RES_IOPORT, 0, &io,
649 					     NULL) == 0) {
650 				xiobase = io;
651 				if (bus_get_resource(idev, SYS_RES_IRQ, 0,
652 				    NULL, NULL) == 0)
653 					outb(xiobase + com_scr, 0x80);
654 				else
655 					outb(xiobase + com_scr, 0);
656 			}
657 			mcr_image = 0;
658 		}
659 	}
660 #endif /* COM_MULTIPORT */
661 	if (bus_get_resource(idev, SYS_RES_IRQ, 0, NULL, NULL) != 0)
662 		mcr_image = 0;
663 
664 	bzero(failures, sizeof failures);
665 	iobase = rman_get_start(port);
666 
667 	/*
668 	 * We don't want to get actual interrupts, just masked ones.
669 	 * Interrupts from this line should already be masked in the ICU,
670 	 * but mask them in the processor as well in case there are some
671 	 * (misconfigured) shared interrupts.
672 	 */
673 	com_lock();
674 /* EXTRA DELAY? */
675 
676 	/*
677 	 * For the TI16754 chips, set prescaler to 1 (4 is often the
678 	 * default after-reset value) as otherwise it's impossible to
679 	 * get highest baudrates.
680 	 */
681 	if (COM_TI16754(flags)) {
682 		u_char cfcr, efr;
683 
684 		cfcr = sio_getreg(com, com_cfcr);
685 		sio_setreg(com, com_cfcr, CFCR_EFR_ENABLE);
686 		efr = sio_getreg(com, com_efr);
687 		/* Unlock extended features to turn off prescaler. */
688 		sio_setreg(com, com_efr, efr | EFR_EFE);
689 		/* Disable EFR. */
690 		sio_setreg(com, com_cfcr, (cfcr != CFCR_EFR_ENABLE) ? cfcr : 0);
691 		/* Turn off prescaler. */
692 		sio_setreg(com, com_mcr,
693 			   sio_getreg(com, com_mcr) & ~MCR_PRESCALE);
694 		sio_setreg(com, com_cfcr, CFCR_EFR_ENABLE);
695 		sio_setreg(com, com_efr, efr);
696 		sio_setreg(com, com_cfcr, cfcr);
697 	}
698 
699 	/*
700 	 * Initialize the speed and the word size and wait long enough to
701 	 * drain the maximum of 16 bytes of junk in device output queues.
702 	 * The speed is undefined after a master reset and must be set
703 	 * before relying on anything related to output.  There may be
704 	 * junk after a (very fast) soft reboot and (apparently) after
705 	 * master reset.
706 	 * XXX what about the UART bug avoided by waiting in comparam()?
707 	 * We don't want to to wait long enough to drain at 2 bps.
708 	 */
709 	if (iobase == siocniobase) {
710 		DELAY((16 + 1) * 1000000 / (comdefaultrate / 10));
711 	} else {
712 		sio_setreg(com, com_cfcr, CFCR_DLAB | CFCR_8BITS);
713 		divisor = siodivisor(rclk, SIO_TEST_SPEED);
714 		sio_setreg(com, com_dlbl, divisor & 0xff);
715 		sio_setreg(com, com_dlbh, divisor >> 8);
716 		sio_setreg(com, com_cfcr, CFCR_8BITS);
717 		DELAY((16 + 1) * 1000000 / (SIO_TEST_SPEED / 10));
718 	}
719 
720 	/*
721 	 * Make sure we can drain the receiver.  If we can't, the serial
722 	 * port may not exist.
723 	 */
724 	for (fn = 0; fn < 256; ++fn) {
725 		if ((sio_getreg(com, com_lsr) & LSR_RXRDY) == 0)
726 			break;
727 		(void)sio_getreg(com, com_data);
728 	}
729 	if (fn == 256) {
730 		printf("sio%d: can't drain, serial port might "
731 			"not exist, disabling\n", device_get_unit(dev));
732 		com_unlock();
733 		return (ENXIO);
734 	}
735 
736 	/*
737 	 * Enable the interrupt gate and disable device interupts.  This
738 	 * should leave the device driving the interrupt line low and
739 	 * guarantee an edge trigger if an interrupt can be generated.
740 	 */
741 /* EXTRA DELAY? */
742 	sio_setreg(com, com_mcr, mcr_image);
743 	sio_setreg(com, com_ier, 0);
744 	DELAY(1000);		/* XXX */
745 	irqmap[0] = isa_irq_pending();
746 
747 	/*
748 	 * Attempt to set loopback mode so that we can send a null byte
749 	 * without annoying any external device.
750 	 */
751 /* EXTRA DELAY? */
752 	sio_setreg(com, com_mcr, mcr_image | MCR_LOOPBACK);
753 
754 	/*
755 	 * Attempt to generate an output interrupt.  On 8250's, setting
756 	 * IER_ETXRDY generates an interrupt independent of the current
757 	 * setting and independent of whether the THR is empty.  On 16450's,
758 	 * setting IER_ETXRDY generates an interrupt independent of the
759 	 * current setting.  On 16550A's, setting IER_ETXRDY only
760 	 * generates an interrupt when IER_ETXRDY is not already set.
761 	 */
762 	sio_setreg(com, com_ier, IER_ETXRDY);
763 
764 	/*
765 	 * On some 16x50 incompatibles, setting IER_ETXRDY doesn't generate
766 	 * an interrupt.  They'd better generate one for actually doing
767 	 * output.  Loopback may be broken on the same incompatibles but
768 	 * it's unlikely to do more than allow the null byte out.
769 	 */
770 	sio_setreg(com, com_data, 0);
771 	DELAY((1 + 2) * 1000000 / (SIO_TEST_SPEED / 10));
772 
773 	/*
774 	 * Turn off loopback mode so that the interrupt gate works again
775 	 * (MCR_IENABLE was hidden).  This should leave the device driving
776 	 * an interrupt line high.  It doesn't matter if the interrupt
777 	 * line oscillates while we are not looking at it, since interrupts
778 	 * are disabled.
779 	 */
780 /* EXTRA DELAY? */
781 	sio_setreg(com, com_mcr, mcr_image);
782 
783 	/*
784 	 * Some pcmcia cards have the "TXRDY bug", so we check everyone
785 	 * for IIR_TXRDY implementation ( Palido 321s, DC-1S... )
786 	 */
787 	if (COM_NOPROBE(flags)) {
788 		/* Reading IIR register twice */
789 		for (fn = 0; fn < 2; fn ++) {
790 			DELAY(10000);
791 			failures[6] = sio_getreg(com, com_iir);
792 		}
793 		/* Check IIR_TXRDY clear ? */
794 		result = 0;
795 		if (failures[6] & IIR_TXRDY) {
796 			/* Nop, Double check with clearing IER */
797 			sio_setreg(com, com_ier, 0);
798 			if (sio_getreg(com, com_iir) & IIR_NOPEND) {
799 				/* Ok. we're familia this gang */
800 				SET_FLAG(dev, COM_C_IIR_TXRDYBUG);
801 			} else {
802 				/* Unknown, Just omit this chip.. XXX */
803 				result = ENXIO;
804 				sio_setreg(com, com_mcr, 0);
805 			}
806 		} else {
807 			/* OK. this is well-known guys */
808 			CLR_FLAG(dev, COM_C_IIR_TXRDYBUG);
809 		}
810 		sio_setreg(com, com_ier, 0);
811 		sio_setreg(com, com_cfcr, CFCR_8BITS);
812 		com_unlock();
813 		bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
814 		return (iobase == siocniobase ? 0 : result);
815 	}
816 
817 	/*
818 	 * Check that
819 	 *	o the CFCR, IER and MCR in UART hold the values written to them
820 	 *	  (the values happen to be all distinct - this is good for
821 	 *	  avoiding false positive tests from bus echoes).
822 	 *	o an output interrupt is generated and its vector is correct.
823 	 *	o the interrupt goes away when the IIR in the UART is read.
824 	 */
825 /* EXTRA DELAY? */
826 	failures[0] = sio_getreg(com, com_cfcr) - CFCR_8BITS;
827 	failures[1] = sio_getreg(com, com_ier) - IER_ETXRDY;
828 	failures[2] = sio_getreg(com, com_mcr) - mcr_image;
829 	DELAY(10000);		/* Some internal modems need this time */
830 	irqmap[1] = isa_irq_pending();
831 	failures[4] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_TXRDY;
832 	DELAY(1000);		/* XXX */
833 	irqmap[2] = isa_irq_pending();
834 	failures[6] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_NOPEND;
835 
836 	/*
837 	 * Turn off all device interrupts and check that they go off properly.
838 	 * Leave MCR_IENABLE alone.  For ports without a master port, it gates
839 	 * the OUT2 output of the UART to
840 	 * the ICU input.  Closing the gate would give a floating ICU input
841 	 * (unless there is another device driving it) and spurious interrupts.
842 	 * (On the system that this was first tested on, the input floats high
843 	 * and gives a (masked) interrupt as soon as the gate is closed.)
844 	 */
845 	sio_setreg(com, com_ier, 0);
846 	sio_setreg(com, com_cfcr, CFCR_8BITS);	/* dummy to avoid bus echo */
847 	failures[7] = sio_getreg(com, com_ier);
848 	DELAY(1000);		/* XXX */
849 	irqmap[3] = isa_irq_pending();
850 	failures[9] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_NOPEND;
851 
852 	com_unlock();
853 
854 	irqs = irqmap[1] & ~irqmap[0];
855 	if (bus_get_resource(idev, SYS_RES_IRQ, 0, &xirq, NULL) == 0 &&
856 	    ((1 << xirq) & irqs) == 0)
857 		printf(
858 		"sio%d: configured irq %ld not in bitmap of probed irqs %#x\n",
859 		    device_get_unit(dev), xirq, irqs);
860 	if (bootverbose)
861 		printf("sio%d: irq maps: %#x %#x %#x %#x\n",
862 		    device_get_unit(dev),
863 		    irqmap[0], irqmap[1], irqmap[2], irqmap[3]);
864 
865 	result = 0;
866 	for (fn = 0; fn < sizeof failures; ++fn)
867 		if (failures[fn]) {
868 			sio_setreg(com, com_mcr, 0);
869 			result = ENXIO;
870 			if (bootverbose) {
871 				printf("sio%d: probe failed test(s):",
872 				    device_get_unit(dev));
873 				for (fn = 0; fn < sizeof failures; ++fn)
874 					if (failures[fn])
875 						printf(" %d", fn);
876 				printf("\n");
877 			}
878 			break;
879 		}
880 	bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
881 	return (iobase == siocniobase ? 0 : result);
882 }
883 
884 #ifdef COM_ESP
885 static int
886 espattach(com, esp_port)
887 	struct com_s		*com;
888 	Port_t			esp_port;
889 {
890 	u_char	dips;
891 	u_char	val;
892 
893 	/*
894 	 * Check the ESP-specific I/O port to see if we're an ESP
895 	 * card.  If not, return failure immediately.
896 	 */
897 	if ((inb(esp_port) & 0xf3) == 0) {
898 		printf(" port 0x%x is not an ESP board?\n", esp_port);
899 		return (0);
900 	}
901 
902 	/*
903 	 * We've got something that claims to be a Hayes ESP card.
904 	 * Let's hope so.
905 	 */
906 
907 	/* Get the dip-switch configuration */
908 	outb(esp_port + ESP_CMD1, ESP_GETDIPS);
909 	dips = inb(esp_port + ESP_STATUS1);
910 
911 	/*
912 	 * Bits 0,1 of dips say which COM port we are.
913 	 */
914 	if (rman_get_start(com->ioportres) == likely_com_ports[dips & 0x03])
915 		printf(" : ESP");
916 	else {
917 		printf(" esp_port has com %d\n", dips & 0x03);
918 		return (0);
919 	}
920 
921 	/*
922 	 * Check for ESP version 2.0 or later:  bits 4,5,6 = 010.
923 	 */
924 	outb(esp_port + ESP_CMD1, ESP_GETTEST);
925 	val = inb(esp_port + ESP_STATUS1);	/* clear reg 1 */
926 	val = inb(esp_port + ESP_STATUS2);
927 	if ((val & 0x70) < 0x20) {
928 		printf("-old (%o)", val & 0x70);
929 		return (0);
930 	}
931 
932 	/*
933 	 * Check for ability to emulate 16550:  bit 7 == 1
934 	 */
935 	if ((dips & 0x80) == 0) {
936 		printf(" slave");
937 		return (0);
938 	}
939 
940 	/*
941 	 * Okay, we seem to be a Hayes ESP card.  Whee.
942 	 */
943 	com->esp = TRUE;
944 	com->esp_port = esp_port;
945 	return (1);
946 }
947 #endif /* COM_ESP */
948 
949 static int
950 sio_isa_attach(dev)
951 	device_t	dev;
952 {
953 	return (sioattach(dev, 0, 0UL));
954 }
955 
956 int
957 sioattach(dev, xrid, rclk)
958 	device_t	dev;
959 	int		xrid;
960 	u_long		rclk;
961 {
962 	struct com_s	*com;
963 #ifdef COM_ESP
964 	Port_t		*espp;
965 #endif
966 	Port_t		iobase;
967 	int		minorbase;
968 	int		unit;
969 	u_int		flags;
970 	int		rid;
971 	struct resource *port;
972 	int		ret;
973 	static int	did_init;
974 
975 	if (did_init == 0) {
976 		did_init = 1;
977 		callout_init(&sio_timeout_handle);
978 	}
979 
980 	rid = xrid;
981 	port = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid,
982 				  0, ~0, IO_COMSIZE, RF_ACTIVE);
983 	if (!port)
984 		return (ENXIO);
985 
986 	iobase = rman_get_start(port);
987 	unit = device_get_unit(dev);
988 	com = device_get_softc(dev);
989 	flags = device_get_flags(dev);
990 
991 	if (unit >= sio_numunits)
992 		sio_numunits = unit + 1;
993 	/*
994 	 * sioprobe() has initialized the device registers as follows:
995 	 *	o cfcr = CFCR_8BITS.
996 	 *	  It is most important that CFCR_DLAB is off, so that the
997 	 *	  data port is not hidden when we enable interrupts.
998 	 *	o ier = 0.
999 	 *	  Interrupts are only enabled when the line is open.
1000 	 *	o mcr = MCR_IENABLE, or 0 if the port has AST/4 compatible
1001 	 *	  interrupt control register or the config specifies no irq.
1002 	 *	  Keeping MCR_DTR and MCR_RTS off might stop the external
1003 	 *	  device from sending before we are ready.
1004 	 */
1005 	bzero(com, sizeof *com);
1006 	com->unit = unit;
1007 	com->ioportres = port;
1008 	com->bst = rman_get_bustag(port);
1009 	com->bsh = rman_get_bushandle(port);
1010 	com->cfcr_image = CFCR_8BITS;
1011 	com->dtr_wait = 3 * hz;
1012 	callout_init(&com->dtr_ch);
1013 	callout_init(&com->busy_ch);
1014 	com->loses_outints = COM_LOSESOUTINTS(flags) != 0;
1015 	com->no_irq = bus_get_resource(dev, SYS_RES_IRQ, 0, NULL, NULL) != 0;
1016 	com->tx_fifo_size = 1;
1017 	com->obufs[0].l_head = com->obuf1;
1018 	com->obufs[1].l_head = com->obuf2;
1019 
1020 	com->data_port = iobase + com_data;
1021 	com->int_id_port = iobase + com_iir;
1022 	com->modem_ctl_port = iobase + com_mcr;
1023 	com->mcr_image = inb(com->modem_ctl_port);
1024 	com->line_status_port = iobase + com_lsr;
1025 	com->modem_status_port = iobase + com_msr;
1026 	com->intr_ctl_port = iobase + com_ier;
1027 
1028 	if (rclk == 0)
1029 		rclk = DEFAULT_RCLK;
1030 	com->rclk = rclk;
1031 
1032 	/*
1033 	 * We don't use all the flags from <sys/ttydefaults.h> since they
1034 	 * are only relevant for logins.  It's important to have echo off
1035 	 * initially so that the line doesn't start blathering before the
1036 	 * echo flag can be turned off.
1037 	 */
1038 	com->it_in.c_iflag = 0;
1039 	com->it_in.c_oflag = 0;
1040 	com->it_in.c_cflag = TTYDEF_CFLAG;
1041 	com->it_in.c_lflag = 0;
1042 	if (unit == comconsole) {
1043 		com->it_in.c_iflag = TTYDEF_IFLAG;
1044 		com->it_in.c_oflag = TTYDEF_OFLAG;
1045 		com->it_in.c_cflag = TTYDEF_CFLAG | CLOCAL;
1046 		com->it_in.c_lflag = TTYDEF_LFLAG;
1047 		com->lt_out.c_cflag = com->lt_in.c_cflag = CLOCAL;
1048 		com->lt_out.c_ispeed = com->lt_out.c_ospeed =
1049 		com->lt_in.c_ispeed = com->lt_in.c_ospeed =
1050 		com->it_in.c_ispeed = com->it_in.c_ospeed = comdefaultrate;
1051 	} else
1052 		com->it_in.c_ispeed = com->it_in.c_ospeed = TTYDEF_SPEED;
1053 	if (siosetwater(com, com->it_in.c_ispeed) != 0) {
1054 		com_unlock();
1055 		/*
1056 		 * Leave i/o resources allocated if this is a `cn'-level
1057 		 * console, so that other devices can't snarf them.
1058 		 */
1059 		if (iobase != siocniobase)
1060 			bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
1061 		return (ENOMEM);
1062 	}
1063 	com_unlock();
1064 	termioschars(&com->it_in);
1065 	com->it_out = com->it_in;
1066 
1067 	/* attempt to determine UART type */
1068 	printf("sio%d: type", unit);
1069 
1070 
1071 #ifdef COM_MULTIPORT
1072 	if (!COM_ISMULTIPORT(flags) && !COM_IIR_TXRDYBUG(flags))
1073 #else
1074 	if (!COM_IIR_TXRDYBUG(flags))
1075 #endif
1076 	{
1077 		u_char	scr;
1078 		u_char	scr1;
1079 		u_char	scr2;
1080 
1081 		scr = sio_getreg(com, com_scr);
1082 		sio_setreg(com, com_scr, 0xa5);
1083 		scr1 = sio_getreg(com, com_scr);
1084 		sio_setreg(com, com_scr, 0x5a);
1085 		scr2 = sio_getreg(com, com_scr);
1086 		sio_setreg(com, com_scr, scr);
1087 		if (scr1 != 0xa5 || scr2 != 0x5a) {
1088 			printf(" 8250");
1089 			goto determined_type;
1090 		}
1091 	}
1092 	sio_setreg(com, com_fifo, FIFO_ENABLE | FIFO_RX_HIGH);
1093 	DELAY(100);
1094 	com->st16650a = 0;
1095 	switch (inb(com->int_id_port) & IIR_FIFO_MASK) {
1096 	case FIFO_RX_LOW:
1097 		printf(" 16450");
1098 		break;
1099 	case FIFO_RX_MEDL:
1100 		printf(" 16450?");
1101 		break;
1102 	case FIFO_RX_MEDH:
1103 		printf(" 16550?");
1104 		break;
1105 	case FIFO_RX_HIGH:
1106 		if (COM_NOFIFO(flags)) {
1107 			printf(" 16550A fifo disabled");
1108 		} else {
1109 			com->hasfifo = TRUE;
1110 			if (COM_ST16650A(flags)) {
1111 				com->st16650a = 1;
1112 				com->tx_fifo_size = 32;
1113 				printf(" ST16650A");
1114 			} else if (COM_TI16754(flags)) {
1115 				com->tx_fifo_size = 64;
1116 				printf(" TI16754");
1117 			} else {
1118 				com->tx_fifo_size = COM_FIFOSIZE(flags);
1119 				printf(" 16550A");
1120 			}
1121 		}
1122 #ifdef COM_ESP
1123 		for (espp = likely_esp_ports; *espp != 0; espp++)
1124 			if (espattach(com, *espp)) {
1125 				com->tx_fifo_size = 1024;
1126 				break;
1127 			}
1128 #endif
1129 		if (!com->st16650a && !COM_TI16754(flags)) {
1130 			if (!com->tx_fifo_size)
1131 				com->tx_fifo_size = 16;
1132 			else
1133 				printf(" lookalike with %d bytes FIFO",
1134 				    com->tx_fifo_size);
1135 		}
1136 
1137 		break;
1138 	}
1139 
1140 #ifdef COM_ESP
1141 	if (com->esp) {
1142 		/*
1143 		 * Set 16550 compatibility mode.
1144 		 * We don't use the ESP_MODE_SCALE bit to increase the
1145 		 * fifo trigger levels because we can't handle large
1146 		 * bursts of input.
1147 		 * XXX flow control should be set in comparam(), not here.
1148 		 */
1149 		outb(com->esp_port + ESP_CMD1, ESP_SETMODE);
1150 		outb(com->esp_port + ESP_CMD2, ESP_MODE_RTS | ESP_MODE_FIFO);
1151 
1152 		/* Set RTS/CTS flow control. */
1153 		outb(com->esp_port + ESP_CMD1, ESP_SETFLOWTYPE);
1154 		outb(com->esp_port + ESP_CMD2, ESP_FLOW_RTS);
1155 		outb(com->esp_port + ESP_CMD2, ESP_FLOW_CTS);
1156 
1157 		/* Set flow-control levels. */
1158 		outb(com->esp_port + ESP_CMD1, ESP_SETRXFLOW);
1159 		outb(com->esp_port + ESP_CMD2, HIBYTE(768));
1160 		outb(com->esp_port + ESP_CMD2, LOBYTE(768));
1161 		outb(com->esp_port + ESP_CMD2, HIBYTE(512));
1162 		outb(com->esp_port + ESP_CMD2, LOBYTE(512));
1163 	}
1164 #endif /* COM_ESP */
1165 	sio_setreg(com, com_fifo, 0);
1166 determined_type: ;
1167 
1168 #ifdef COM_MULTIPORT
1169 	if (COM_ISMULTIPORT(flags)) {
1170 		device_t masterdev;
1171 
1172 		com->multiport = TRUE;
1173 		printf(" (multiport");
1174 		if (unit == COM_MPMASTER(flags))
1175 			printf(" master");
1176 		printf(")");
1177 		masterdev = devclass_get_device(sio_devclass,
1178 		    COM_MPMASTER(flags));
1179 		com->no_irq = (masterdev == NULL || bus_get_resource(masterdev,
1180 		    SYS_RES_IRQ, 0, NULL, NULL) != 0);
1181 	 }
1182 #endif /* COM_MULTIPORT */
1183 	if (unit == comconsole)
1184 		printf(", console");
1185 	if (COM_IIR_TXRDYBUG(flags))
1186 		printf(" with a bogus IIR_TXRDY register");
1187 	printf("\n");
1188 
1189 	if (!sio_registered) {
1190 		register_swi(SWI_TTY, siopoll, NULL ,"swi_siopoll", NULL);
1191 		sio_registered = TRUE;
1192 	}
1193 	minorbase = UNIT_TO_MINOR(unit);
1194 	dev_ops_add(&sio_ops, UNIT_TO_MINOR(-1), minorbase);
1195 	make_dev(&sio_ops, minorbase,
1196 	    UID_ROOT, GID_WHEEL, 0600, "ttyd%r", unit);
1197 	make_dev(&sio_ops, minorbase | CONTROL_INIT_STATE,
1198 	    UID_ROOT, GID_WHEEL, 0600, "ttyid%r", unit);
1199 	make_dev(&sio_ops, minorbase | CONTROL_LOCK_STATE,
1200 	    UID_ROOT, GID_WHEEL, 0600, "ttyld%r", unit);
1201 	make_dev(&sio_ops, minorbase | CALLOUT_MASK,
1202 	    UID_UUCP, GID_DIALER, 0660, "cuaa%r", unit);
1203 	make_dev(&sio_ops, minorbase | CALLOUT_MASK | CONTROL_INIT_STATE,
1204 	    UID_UUCP, GID_DIALER, 0660, "cuaia%r", unit);
1205 	make_dev(&sio_ops, minorbase | CALLOUT_MASK | CONTROL_LOCK_STATE,
1206 	    UID_UUCP, GID_DIALER, 0660, "cuala%r", unit);
1207 	com->flags = flags;
1208 	com->pps.ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR;
1209 	pps_init(&com->pps);
1210 
1211 	rid = 0;
1212 	com->irqres = bus_alloc_resource(dev, SYS_RES_IRQ, &rid, 0ul, ~0ul, 1,
1213 	    RF_ACTIVE);
1214 	if (com->irqres) {
1215 		ret = BUS_SETUP_INTR(device_get_parent(dev), dev, com->irqres,
1216 				     INTR_FAST, siointr, com,
1217 				     &com->cookie, NULL);
1218 		if (ret) {
1219 			ret = BUS_SETUP_INTR(device_get_parent(dev), dev,
1220 					     com->irqres, 0, siointr, com,
1221 					     &com->cookie, NULL);
1222 			if (ret == 0)
1223 				device_printf(dev, "unable to activate interrupt in fast mode - using normal mode\n");
1224 		}
1225 		if (ret)
1226 			device_printf(dev, "could not activate interrupt\n");
1227 #if defined(DDB) && (defined(BREAK_TO_DEBUGGER) || \
1228     defined(ALT_BREAK_TO_DEBUGGER))
1229 		/*
1230 		 * Enable interrupts for early break-to-debugger support
1231 		 * on the console.
1232 		 */
1233 		if (ret == 0 && unit == comconsole)
1234 			outb(siocniobase + com_ier, IER_ERXRDY | IER_ERLS |
1235 			    IER_EMSC);
1236 #endif
1237 	}
1238 
1239 	return (0);
1240 }
1241 
1242 static int
1243 sioopen(struct dev_open_args *ap)
1244 {
1245 	cdev_t dev = ap->a_head.a_dev;
1246 	struct com_s	*com;
1247 	int		error;
1248 	int		mynor;
1249 	struct tty	*tp;
1250 	int		unit;
1251 
1252 	mynor = minor(dev);
1253 	unit = MINOR_TO_UNIT(mynor);
1254 	com = com_addr(unit);
1255 	if (com == NULL)
1256 		return (ENXIO);
1257 	if (com->gone)
1258 		return (ENXIO);
1259 	if (mynor & CONTROL_MASK)
1260 		return (0);
1261 	tp = dev->si_tty = com->tp = ttymalloc(com->tp);
1262 	crit_enter();
1263 	/*
1264 	 * We jump to this label after all non-interrupted sleeps to pick
1265 	 * up any changes of the device state.
1266 	 */
1267 open_top:
1268 	while (com->state & CS_DTR_OFF) {
1269 		error = tsleep(&com->dtr_wait, PCATCH, "siodtr", 0);
1270 		if (com_addr(unit) == NULL) {
1271 			crit_exit();
1272 			return (ENXIO);
1273 		}
1274 		if (error != 0 || com->gone)
1275 			goto out;
1276 	}
1277 	if (tp->t_state & TS_ISOPEN) {
1278 		/*
1279 		 * The device is open, so everything has been initialized.
1280 		 * Handle conflicts.
1281 		 */
1282 		if (mynor & CALLOUT_MASK) {
1283 			if (!com->active_out) {
1284 				error = EBUSY;
1285 				goto out;
1286 			}
1287 		} else {
1288 			if (com->active_out) {
1289 				if (ap->a_oflags & O_NONBLOCK) {
1290 					error = EBUSY;
1291 					goto out;
1292 				}
1293 				error =	tsleep(&com->active_out,
1294 					       PCATCH, "siobi", 0);
1295 				if (com_addr(unit) == NULL) {
1296 					crit_exit();
1297 					return (ENXIO);
1298 				}
1299 				if (error != 0 || com->gone)
1300 					goto out;
1301 				goto open_top;
1302 			}
1303 		}
1304 		if (tp->t_state & TS_XCLUDE && suser_cred(ap->a_cred, 0)) {
1305 			error = EBUSY;
1306 			goto out;
1307 		}
1308 	} else {
1309 		/*
1310 		 * The device isn't open, so there are no conflicts.
1311 		 * Initialize it.  Initialization is done twice in many
1312 		 * cases: to preempt sleeping callin opens if we are
1313 		 * callout, and to complete a callin open after DCD rises.
1314 		 */
1315 		tp->t_oproc = comstart;
1316 		tp->t_param = comparam;
1317 		tp->t_stop = comstop;
1318 		tp->t_dev = dev;
1319 		tp->t_termios = mynor & CALLOUT_MASK
1320 				? com->it_out : com->it_in;
1321 		(void)commctl(com, TIOCM_DTR | TIOCM_RTS, DMSET);
1322 		com->poll = com->no_irq;
1323 		com->poll_output = com->loses_outints;
1324 		++com->wopeners;
1325 		error = comparam(tp, &tp->t_termios);
1326 		--com->wopeners;
1327 		if (error != 0)
1328 			goto out;
1329 		/*
1330 		 * XXX we should goto open_top if comparam() slept.
1331 		 */
1332 		if (com->hasfifo) {
1333 			/*
1334 			 * (Re)enable and drain fifos.
1335 			 *
1336 			 * Certain SMC chips cause problems if the fifos
1337 			 * are enabled while input is ready.  Turn off the
1338 			 * fifo if necessary to clear the input.  We test
1339 			 * the input ready bit after enabling the fifos
1340 			 * since we've already enabled them in comparam()
1341 			 * and to handle races between enabling and fresh
1342 			 * input.
1343 			 */
1344 			while (TRUE) {
1345 				sio_setreg(com, com_fifo,
1346 					   FIFO_RCV_RST | FIFO_XMT_RST
1347 					   | com->fifo_image);
1348 				/*
1349 				 * XXX the delays are for superstitious
1350 				 * historical reasons.  It must be less than
1351 				 * the character time at the maximum
1352 				 * supported speed (87 usec at 115200 bps
1353 				 * 8N1).  Otherwise we might loop endlessly
1354 				 * if data is streaming in.  We used to use
1355 				 * delays of 100.  That usually worked
1356 				 * because DELAY(100) used to usually delay
1357 				 * for about 85 usec instead of 100.
1358 				 */
1359 				DELAY(50);
1360 				if (!(inb(com->line_status_port) & LSR_RXRDY))
1361 					break;
1362 				sio_setreg(com, com_fifo, 0);
1363 				DELAY(50);
1364 				(void) inb(com->data_port);
1365 			}
1366 		}
1367 
1368 		com_lock();
1369 		(void) inb(com->line_status_port);
1370 		(void) inb(com->data_port);
1371 		com->prev_modem_status = com->last_modem_status
1372 		    = inb(com->modem_status_port);
1373 		if (COM_IIR_TXRDYBUG(com->flags)) {
1374 			outb(com->intr_ctl_port, IER_ERXRDY | IER_ERLS
1375 						| IER_EMSC);
1376 		} else {
1377 			outb(com->intr_ctl_port, IER_ERXRDY | IER_ETXRDY
1378 						| IER_ERLS | IER_EMSC);
1379 		}
1380 		com_unlock();
1381 		/*
1382 		 * Handle initial DCD.  Callout devices get a fake initial
1383 		 * DCD (trapdoor DCD).  If we are callout, then any sleeping
1384 		 * callin opens get woken up and resume sleeping on "siobi"
1385 		 * instead of "siodcd".
1386 		 */
1387 		/*
1388 		 * XXX `mynor & CALLOUT_MASK' should be
1389 		 * `tp->t_cflag & (SOFT_CARRIER | TRAPDOOR_CARRIER) where
1390 		 * TRAPDOOR_CARRIER is the default initial state for callout
1391 		 * devices and SOFT_CARRIER is like CLOCAL except it hides
1392 		 * the true carrier.
1393 		 */
1394 		if (com->prev_modem_status & MSR_DCD || mynor & CALLOUT_MASK)
1395 			(*linesw[tp->t_line].l_modem)(tp, 1);
1396 	}
1397 	/*
1398 	 * Wait for DCD if necessary.
1399 	 */
1400 	if (!(tp->t_state & TS_CARR_ON) && !(mynor & CALLOUT_MASK)
1401 	    && !(tp->t_cflag & CLOCAL) && !(ap->a_oflags & O_NONBLOCK)) {
1402 		++com->wopeners;
1403 		error = tsleep(TSA_CARR_ON(tp), PCATCH, "siodcd", 0);
1404 		if (com_addr(unit) == NULL) {
1405 			crit_exit();
1406 			return (ENXIO);
1407 		}
1408 		--com->wopeners;
1409 		if (error != 0 || com->gone)
1410 			goto out;
1411 		goto open_top;
1412 	}
1413 	error =	(*linesw[tp->t_line].l_open)(dev, tp);
1414 	disc_optim(tp, &tp->t_termios, com);
1415 	if (tp->t_state & TS_ISOPEN && mynor & CALLOUT_MASK)
1416 		com->active_out = TRUE;
1417 	siosettimeout();
1418 out:
1419 	crit_exit();
1420 	if (!(tp->t_state & TS_ISOPEN) && com->wopeners == 0)
1421 		comhardclose(com);
1422 	return (error);
1423 }
1424 
1425 static int
1426 sioclose(struct dev_close_args *ap)
1427 {
1428 	cdev_t dev = ap->a_head.a_dev;
1429 	struct com_s	*com;
1430 	int		mynor;
1431 	struct tty	*tp;
1432 
1433 	mynor = minor(dev);
1434 	if (mynor & CONTROL_MASK)
1435 		return (0);
1436 	com = com_addr(MINOR_TO_UNIT(mynor));
1437 	if (com == NULL)
1438 		return (ENODEV);
1439 	tp = com->tp;
1440 	crit_enter();
1441 	(*linesw[tp->t_line].l_close)(tp, ap->a_fflag);
1442 	disc_optim(tp, &tp->t_termios, com);
1443 	comstop(tp, FREAD | FWRITE);
1444 	comhardclose(com);
1445 	ttyclose(tp);
1446 	siosettimeout();
1447 	crit_exit();
1448 	if (com->gone) {
1449 		printf("sio%d: gone\n", com->unit);
1450 		crit_enter();
1451 		if (com->ibuf != NULL)
1452 			kfree(com->ibuf, M_DEVBUF);
1453 		bzero(tp, sizeof *tp);
1454 		crit_exit();
1455 	}
1456 	return (0);
1457 }
1458 
1459 static void
1460 comhardclose(com)
1461 	struct com_s	*com;
1462 {
1463 	struct tty	*tp;
1464 	int		unit;
1465 
1466 	unit = com->unit;
1467 	crit_enter();
1468 	com->poll = FALSE;
1469 	com->poll_output = FALSE;
1470 	com->do_timestamp = FALSE;
1471 	com->do_dcd_timestamp = FALSE;
1472 	com->pps.ppsparam.mode = 0;
1473 	sio_setreg(com, com_cfcr, com->cfcr_image &= ~CFCR_SBREAK);
1474 	tp = com->tp;
1475 
1476 #if defined(DDB) && (defined(BREAK_TO_DEBUGGER) || \
1477     defined(ALT_BREAK_TO_DEBUGGER))
1478 	/*
1479 	 * Leave interrupts enabled and don't clear DTR if this is the
1480 	 * console. This allows us to detect break-to-debugger events
1481 	 * while the console device is closed.
1482 	 */
1483 	if (com->unit != comconsole)
1484 #endif
1485 	{
1486 		sio_setreg(com, com_ier, 0);
1487 		if (tp->t_cflag & HUPCL
1488 		    /*
1489 		     * XXX we will miss any carrier drop between here and the
1490 		     * next open.  Perhaps we should watch DCD even when the
1491 		     * port is closed; it is not sufficient to check it at
1492 		     * the next open because it might go up and down while
1493 		     * we're not watching.
1494 		     */
1495 		    || (!com->active_out
1496 		        && !(com->prev_modem_status & MSR_DCD)
1497 		        && !(com->it_in.c_cflag & CLOCAL))
1498 		    || !(tp->t_state & TS_ISOPEN)) {
1499 			(void)commctl(com, TIOCM_DTR, DMBIC);
1500 			if (com->dtr_wait != 0 && !(com->state & CS_DTR_OFF)) {
1501 				callout_reset(&com->dtr_ch, com->dtr_wait,
1502 						siodtrwakeup, com);
1503 				com->state |= CS_DTR_OFF;
1504 			}
1505 		}
1506 	}
1507 	if (com->hasfifo) {
1508 		/*
1509 		 * Disable fifos so that they are off after controlled
1510 		 * reboots.  Some BIOSes fail to detect 16550s when the
1511 		 * fifos are enabled.
1512 		 */
1513 		sio_setreg(com, com_fifo, 0);
1514 	}
1515 	com->active_out = FALSE;
1516 	wakeup(&com->active_out);
1517 	wakeup(TSA_CARR_ON(tp));	/* restart any wopeners */
1518 	crit_exit();
1519 }
1520 
1521 static int
1522 sioread(struct dev_read_args *ap)
1523 {
1524 	cdev_t dev = ap->a_head.a_dev;
1525 	int		mynor;
1526 	struct com_s	*com;
1527 
1528 	mynor = minor(dev);
1529 	if (mynor & CONTROL_MASK)
1530 		return (ENODEV);
1531 	com = com_addr(MINOR_TO_UNIT(mynor));
1532 	if (com == NULL || com->gone)
1533 		return (ENODEV);
1534 	return ((*linesw[com->tp->t_line].l_read)(com->tp, ap->a_uio, ap->a_ioflag));
1535 }
1536 
1537 static int
1538 siowrite(struct dev_write_args *ap)
1539 {
1540 	cdev_t dev = ap->a_head.a_dev;
1541 	int		mynor;
1542 	struct com_s	*com;
1543 	int		unit;
1544 
1545 	mynor = minor(dev);
1546 	if (mynor & CONTROL_MASK)
1547 		return (ENODEV);
1548 
1549 	unit = MINOR_TO_UNIT(mynor);
1550 	com = com_addr(unit);
1551 	if (com == NULL || com->gone)
1552 		return (ENODEV);
1553 	/*
1554 	 * (XXX) We disallow virtual consoles if the physical console is
1555 	 * a serial port.  This is in case there is a display attached that
1556 	 * is not the console.  In that situation we don't need/want the X
1557 	 * server taking over the console.
1558 	 */
1559 	if (constty != NULL && unit == comconsole)
1560 		constty = NULL;
1561 	return ((*linesw[com->tp->t_line].l_write)(com->tp, ap->a_uio, ap->a_ioflag));
1562 }
1563 
1564 static void
1565 siobusycheck(chan)
1566 	void	*chan;
1567 {
1568 	struct com_s	*com;
1569 
1570 	com = (struct com_s *)chan;
1571 
1572 	/*
1573 	 * Clear TS_BUSY if low-level output is complete.
1574 	 * spl locking is sufficient because siointr1() does not set CS_BUSY.
1575 	 * If siointr1() clears CS_BUSY after we look at it, then we'll get
1576 	 * called again.  Reading the line status port outside of siointr1()
1577 	 * is safe because CS_BUSY is clear so there are no output interrupts
1578 	 * to lose.
1579 	 */
1580 	crit_enter();
1581 	if (com->state & CS_BUSY)
1582 		com->extra_state &= ~CSE_BUSYCHECK;	/* False alarm. */
1583 	else if ((inb(com->line_status_port) & (LSR_TSRE | LSR_TXRDY))
1584 	    == (LSR_TSRE | LSR_TXRDY)) {
1585 		com->tp->t_state &= ~TS_BUSY;
1586 		ttwwakeup(com->tp);
1587 		com->extra_state &= ~CSE_BUSYCHECK;
1588 	} else {
1589 		callout_reset(&com->busy_ch, hz / 100, siobusycheck, com);
1590 	}
1591 	crit_exit();
1592 }
1593 
1594 static u_int
1595 siodivisor(rclk, speed)
1596 	u_long	rclk;
1597 	speed_t	speed;
1598 {
1599 	long	actual_speed;
1600 	u_int	divisor;
1601 	int	error;
1602 
1603 	if (speed == 0 || speed > (ULONG_MAX - 1) / 8)
1604 		return (0);
1605 	divisor = (rclk / (8UL * speed) + 1) / 2;
1606 	if (divisor == 0 || divisor >= 65536)
1607 		return (0);
1608 	actual_speed = rclk / (16UL * divisor);
1609 
1610 	/* 10 times error in percent: */
1611 	error = ((actual_speed - (long)speed) * 2000 / (long)speed + 1) / 2;
1612 
1613 	/* 3.0% maximum error tolerance: */
1614 	if (error < -30 || error > 30)
1615 		return (0);
1616 
1617 	return (divisor);
1618 }
1619 
1620 static void
1621 siodtrwakeup(chan)
1622 	void	*chan;
1623 {
1624 	struct com_s	*com;
1625 
1626 	com = (struct com_s *)chan;
1627 	com->state &= ~CS_DTR_OFF;
1628 	wakeup(&com->dtr_wait);
1629 }
1630 
1631 static void
1632 sioinput(com)
1633 	struct com_s	*com;
1634 {
1635 	u_char		*buf;
1636 	int		incc;
1637 	u_char		line_status;
1638 	int		recv_data;
1639 	struct tty	*tp;
1640 
1641 	buf = com->ibuf;
1642 	tp = com->tp;
1643 	if (!(tp->t_state & TS_ISOPEN) || !(tp->t_cflag & CREAD)) {
1644 		com_events -= (com->iptr - com->ibuf);
1645 		com->iptr = com->ibuf;
1646 		return;
1647 	}
1648 	if (tp->t_state & TS_CAN_BYPASS_L_RINT) {
1649 		/*
1650 		 * Avoid the grotesquely inefficient lineswitch routine
1651 		 * (ttyinput) in "raw" mode.  It usually takes about 450
1652 		 * instructions (that's without canonical processing or echo!).
1653 		 * slinput is reasonably fast (usually 40 instructions plus
1654 		 * call overhead).
1655 		 */
1656 		do {
1657 			com_unlock();
1658 			incc = com->iptr - buf;
1659 			if (tp->t_rawq.c_cc + incc > tp->t_ihiwat
1660 			    && (com->state & CS_RTS_IFLOW
1661 				|| tp->t_iflag & IXOFF)
1662 			    && !(tp->t_state & TS_TBLOCK))
1663 				ttyblock(tp);
1664 			com->delta_error_counts[CE_TTY_BUF_OVERFLOW]
1665 				+= b_to_q((char *)buf, incc, &tp->t_rawq);
1666 			buf += incc;
1667 			tk_nin += incc;
1668 			tk_rawcc += incc;
1669 			tp->t_rawcc += incc;
1670 			ttwakeup(tp);
1671 			if (tp->t_state & TS_TTSTOP
1672 			    && (tp->t_iflag & IXANY
1673 				|| tp->t_cc[VSTART] == tp->t_cc[VSTOP])) {
1674 				tp->t_state &= ~TS_TTSTOP;
1675 				tp->t_lflag &= ~FLUSHO;
1676 				comstart(tp);
1677 			}
1678 			com_lock();
1679 		} while (buf < com->iptr);
1680 	} else {
1681 		do {
1682 			com_unlock();
1683 			line_status = buf[com->ierroff];
1684 			recv_data = *buf++;
1685 			if (line_status
1686 			    & (LSR_BI | LSR_FE | LSR_OE | LSR_PE)) {
1687 				if (line_status & LSR_BI)
1688 					recv_data |= TTY_BI;
1689 				if (line_status & LSR_FE)
1690 					recv_data |= TTY_FE;
1691 				if (line_status & LSR_OE)
1692 					recv_data |= TTY_OE;
1693 				if (line_status & LSR_PE)
1694 					recv_data |= TTY_PE;
1695 			}
1696 			(*linesw[tp->t_line].l_rint)(recv_data, tp);
1697 			com_lock();
1698 		} while (buf < com->iptr);
1699 	}
1700 	com_events -= (com->iptr - com->ibuf);
1701 	com->iptr = com->ibuf;
1702 
1703 	/*
1704 	 * There is now room for another low-level buffer full of input,
1705 	 * so enable RTS if it is now disabled and there is room in the
1706 	 * high-level buffer.
1707 	 */
1708 	if ((com->state & CS_RTS_IFLOW) && !(com->mcr_image & MCR_RTS) &&
1709 	    !(tp->t_state & TS_TBLOCK))
1710 		outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
1711 }
1712 
1713 void
1714 siointr(arg)
1715 	void		*arg;
1716 {
1717 #ifndef COM_MULTIPORT
1718 	com_lock();
1719 	siointr1((struct com_s *) arg);
1720 	com_unlock();
1721 #else /* COM_MULTIPORT */
1722 	bool_t		possibly_more_intrs;
1723 	int		unit;
1724 	struct com_s	*com;
1725 
1726 	/*
1727 	 * Loop until there is no activity on any port.  This is necessary
1728 	 * to get an interrupt edge more than to avoid another interrupt.
1729 	 * If the IRQ signal is just an OR of the IRQ signals from several
1730 	 * devices, then the edge from one may be lost because another is
1731 	 * on.
1732 	 */
1733 	com_lock();
1734 	do {
1735 		possibly_more_intrs = FALSE;
1736 		for (unit = 0; unit < sio_numunits; ++unit) {
1737 			com = com_addr(unit);
1738 			/*
1739 			 * XXX com_lock();
1740 			 * would it work here, or be counter-productive?
1741 			 */
1742 			if (com != NULL
1743 			    && !com->gone
1744 			    && (inb(com->int_id_port) & IIR_IMASK)
1745 			       != IIR_NOPEND) {
1746 				siointr1(com);
1747 				possibly_more_intrs = TRUE;
1748 			}
1749 			/* XXX com_unlock(); */
1750 		}
1751 	} while (possibly_more_intrs);
1752 	com_unlock();
1753 #endif /* COM_MULTIPORT */
1754 }
1755 
1756 static void
1757 siointr1(com)
1758 	struct com_s	*com;
1759 {
1760 	u_char	line_status;
1761 	u_char	modem_status;
1762 	u_char	*ioptr;
1763 	u_char	recv_data;
1764 	u_char	int_ctl;
1765 	u_char	int_ctl_new;
1766 	u_int	count;
1767 
1768 	int_ctl = inb(com->intr_ctl_port);
1769 	int_ctl_new = int_ctl;
1770 
1771 	while (!com->gone) {
1772 		if (com->pps.ppsparam.mode & PPS_CAPTUREBOTH) {
1773 			modem_status = inb(com->modem_status_port);
1774 		        if ((modem_status ^ com->last_modem_status) & MSR_DCD) {
1775 				count = sys_cputimer->count();
1776 				pps_event(&com->pps, count,
1777 				    (modem_status & MSR_DCD) ?
1778 				    PPS_CAPTUREASSERT : PPS_CAPTURECLEAR);
1779 			}
1780 		}
1781 		line_status = inb(com->line_status_port);
1782 
1783 		/* input event? (check first to help avoid overruns) */
1784 		while (line_status & LSR_RCV_MASK) {
1785 			/* break/unnattached error bits or real input? */
1786 			if (!(line_status & LSR_RXRDY))
1787 				recv_data = 0;
1788 			else
1789 				recv_data = inb(com->data_port);
1790 #if defined(DDB) && defined(ALT_BREAK_TO_DEBUGGER)
1791 			/*
1792 			 * Solaris implements a new BREAK which is initiated
1793 			 * by a character sequence CR ~ ^b which is similar
1794 			 * to a familiar pattern used on Sun servers by the
1795 			 * Remote Console.
1796 			 */
1797 #define	KEY_CRTLB	2	/* ^B */
1798 #define	KEY_CR		13	/* CR '\r' */
1799 #define	KEY_TILDE	126	/* ~ */
1800 
1801 			if (com->unit == comconsole) {
1802 				static int brk_state1 = 0, brk_state2 = 0;
1803 				if (recv_data == KEY_CR) {
1804 					brk_state1 = recv_data;
1805 					brk_state2 = 0;
1806 				} else if (brk_state1 == KEY_CR && (recv_data == KEY_TILDE || recv_data == KEY_CRTLB)) {
1807 					if (recv_data == KEY_TILDE)
1808 						brk_state2 = recv_data;
1809 					else if (brk_state2 == KEY_TILDE && recv_data == KEY_CRTLB) {
1810 							breakpoint();
1811 							brk_state1 = brk_state2 = 0;
1812 							goto cont;
1813 					} else
1814 						brk_state2 = 0;
1815 				} else
1816 					brk_state1 = 0;
1817 			}
1818 #endif
1819 			if (line_status & (LSR_BI | LSR_FE | LSR_PE)) {
1820 				/*
1821 				 * Don't store BI if IGNBRK or FE/PE if IGNPAR.
1822 				 * Otherwise, push the work to a higher level
1823 				 * (to handle PARMRK) if we're bypassing.
1824 				 * Otherwise, convert BI/FE and PE+INPCK to 0.
1825 				 *
1826 				 * This makes bypassing work right in the
1827 				 * usual "raw" case (IGNBRK set, and IGNPAR
1828 				 * and INPCK clear).
1829 				 *
1830 				 * Note: BI together with FE/PE means just BI.
1831 				 */
1832 				if (line_status & LSR_BI) {
1833 #if defined(DDB) && defined(BREAK_TO_DEBUGGER)
1834 					if (com->unit == comconsole) {
1835 						breakpoint();
1836 						goto cont;
1837 					}
1838 #endif
1839 					if (com->tp == NULL
1840 					    || com->tp->t_iflag & IGNBRK)
1841 						goto cont;
1842 				} else {
1843 					if (com->tp == NULL
1844 					    || com->tp->t_iflag & IGNPAR)
1845 						goto cont;
1846 				}
1847 				if (com->tp->t_state & TS_CAN_BYPASS_L_RINT
1848 				    && (line_status & (LSR_BI | LSR_FE)
1849 					|| com->tp->t_iflag & INPCK))
1850 					recv_data = 0;
1851 			}
1852 			++com->bytes_in;
1853 			if (com->hotchar != 0 && recv_data == com->hotchar)
1854 				setsofttty();
1855 			ioptr = com->iptr;
1856 			if (ioptr >= com->ibufend)
1857 				CE_RECORD(com, CE_INTERRUPT_BUF_OVERFLOW);
1858 			else {
1859 				if (com->do_timestamp)
1860 					microtime(&com->timestamp);
1861 				++com_events;
1862 				schedsofttty();
1863 #if 0 /* for testing input latency vs efficiency */
1864 if (com->iptr - com->ibuf == 8)
1865 	setsofttty();
1866 #endif
1867 				ioptr[0] = recv_data;
1868 				ioptr[com->ierroff] = line_status;
1869 				com->iptr = ++ioptr;
1870 				if (ioptr == com->ihighwater
1871 				    && com->state & CS_RTS_IFLOW)
1872 					outb(com->modem_ctl_port,
1873 					     com->mcr_image &= ~MCR_RTS);
1874 				if (line_status & LSR_OE)
1875 					CE_RECORD(com, CE_OVERRUN);
1876 			}
1877 cont:
1878 			/*
1879 			 * "& 0x7F" is to avoid the gcc-1.40 generating a slow
1880 			 * jump from the top of the loop to here
1881 			 */
1882 			line_status = inb(com->line_status_port) & 0x7F;
1883 		}
1884 
1885 		/* modem status change? (always check before doing output) */
1886 		modem_status = inb(com->modem_status_port);
1887 		if (modem_status != com->last_modem_status) {
1888 			if (com->do_dcd_timestamp
1889 			    && !(com->last_modem_status & MSR_DCD)
1890 			    && modem_status & MSR_DCD)
1891 				microtime(&com->dcd_timestamp);
1892 
1893 			/*
1894 			 * Schedule high level to handle DCD changes.  Note
1895 			 * that we don't use the delta bits anywhere.  Some
1896 			 * UARTs mess them up, and it's easy to remember the
1897 			 * previous bits and calculate the delta.
1898 			 */
1899 			com->last_modem_status = modem_status;
1900 			if (!(com->state & CS_CHECKMSR)) {
1901 				com_events += LOTS_OF_EVENTS;
1902 				com->state |= CS_CHECKMSR;
1903 				setsofttty();
1904 			}
1905 
1906 			/* handle CTS change immediately for crisp flow ctl */
1907 			if (com->state & CS_CTS_OFLOW) {
1908 				if (modem_status & MSR_CTS)
1909 					com->state |= CS_ODEVREADY;
1910 				else
1911 					com->state &= ~CS_ODEVREADY;
1912 			}
1913 		}
1914 
1915 		/* output queued and everything ready? */
1916 		if (line_status & LSR_TXRDY
1917 		    && com->state >= (CS_BUSY | CS_TTGO | CS_ODEVREADY)) {
1918 			ioptr = com->obufq.l_head;
1919 			if (com->tx_fifo_size > 1) {
1920 				u_int	ocount;
1921 
1922 				ocount = com->obufq.l_tail - ioptr;
1923 				if (ocount > com->tx_fifo_size)
1924 					ocount = com->tx_fifo_size;
1925 				com->bytes_out += ocount;
1926 				do
1927 					outb(com->data_port, *ioptr++);
1928 				while (--ocount != 0);
1929 			} else {
1930 				outb(com->data_port, *ioptr++);
1931 				++com->bytes_out;
1932 			}
1933 			com->obufq.l_head = ioptr;
1934 			if (COM_IIR_TXRDYBUG(com->flags)) {
1935 				int_ctl_new = int_ctl | IER_ETXRDY;
1936 			}
1937 			if (ioptr >= com->obufq.l_tail) {
1938 				struct lbq	*qp;
1939 
1940 				qp = com->obufq.l_next;
1941 				qp->l_queued = FALSE;
1942 				qp = qp->l_next;
1943 				if (qp != NULL) {
1944 					com->obufq.l_head = qp->l_head;
1945 					com->obufq.l_tail = qp->l_tail;
1946 					com->obufq.l_next = qp;
1947 				} else {
1948 					/* output just completed */
1949 					if (COM_IIR_TXRDYBUG(com->flags)) {
1950 						int_ctl_new = int_ctl & ~IER_ETXRDY;
1951 					}
1952 					com->state &= ~CS_BUSY;
1953 				}
1954 				if (!(com->state & CS_ODONE)) {
1955 					com_events += LOTS_OF_EVENTS;
1956 					com->state |= CS_ODONE;
1957 					setsofttty();	/* handle at high level ASAP */
1958 				}
1959 			}
1960 			if (COM_IIR_TXRDYBUG(com->flags) && (int_ctl != int_ctl_new)) {
1961 				outb(com->intr_ctl_port, int_ctl_new);
1962 			}
1963 		}
1964 
1965 		/* finished? */
1966 #ifndef COM_MULTIPORT
1967 		if ((inb(com->int_id_port) & IIR_IMASK) == IIR_NOPEND)
1968 #endif /* COM_MULTIPORT */
1969 			return;
1970 	}
1971 }
1972 
1973 static int
1974 sioioctl(struct dev_ioctl_args *ap)
1975 {
1976 	cdev_t dev = ap->a_head.a_dev;
1977 	caddr_t data = ap->a_data;
1978 	struct com_s	*com;
1979 	int		error;
1980 	int		mynor;
1981 	struct tty	*tp;
1982 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
1983 	u_long		oldcmd;
1984 	struct termios	term;
1985 #endif
1986 
1987 	mynor = minor(dev);
1988 	com = com_addr(MINOR_TO_UNIT(mynor));
1989 	if (com == NULL || com->gone)
1990 		return (ENODEV);
1991 	if (mynor & CONTROL_MASK) {
1992 		struct termios	*ct;
1993 
1994 		switch (mynor & CONTROL_MASK) {
1995 		case CONTROL_INIT_STATE:
1996 			ct = mynor & CALLOUT_MASK ? &com->it_out : &com->it_in;
1997 			break;
1998 		case CONTROL_LOCK_STATE:
1999 			ct = mynor & CALLOUT_MASK ? &com->lt_out : &com->lt_in;
2000 			break;
2001 		default:
2002 			return (ENODEV);	/* /dev/nodev */
2003 		}
2004 		switch (ap->a_cmd) {
2005 		case TIOCSETA:
2006 			error = suser_cred(ap->a_cred, 0);
2007 			if (error != 0)
2008 				return (error);
2009 			*ct = *(struct termios *)data;
2010 			return (0);
2011 		case TIOCGETA:
2012 			*(struct termios *)data = *ct;
2013 			return (0);
2014 		case TIOCGETD:
2015 			*(int *)data = TTYDISC;
2016 			return (0);
2017 		case TIOCGWINSZ:
2018 			bzero(data, sizeof(struct winsize));
2019 			return (0);
2020 		default:
2021 			return (ENOTTY);
2022 		}
2023 	}
2024 	tp = com->tp;
2025 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
2026 	term = tp->t_termios;
2027 	oldcmd = ap->a_cmd;
2028 	error = ttsetcompat(tp, &ap->a_cmd, data, &term);
2029 	if (error != 0)
2030 		return (error);
2031 	if (ap->a_cmd != oldcmd)
2032 		data = (caddr_t)&term;
2033 #endif
2034 	if (ap->a_cmd == TIOCSETA || ap->a_cmd == TIOCSETAW ||
2035 	    ap->a_cmd == TIOCSETAF) {
2036 		int	cc;
2037 		struct termios *dt = (struct termios *)data;
2038 		struct termios *lt = mynor & CALLOUT_MASK
2039 				     ? &com->lt_out : &com->lt_in;
2040 
2041 		dt->c_iflag = (tp->t_iflag & lt->c_iflag)
2042 			      | (dt->c_iflag & ~lt->c_iflag);
2043 		dt->c_oflag = (tp->t_oflag & lt->c_oflag)
2044 			      | (dt->c_oflag & ~lt->c_oflag);
2045 		dt->c_cflag = (tp->t_cflag & lt->c_cflag)
2046 			      | (dt->c_cflag & ~lt->c_cflag);
2047 		dt->c_lflag = (tp->t_lflag & lt->c_lflag)
2048 			      | (dt->c_lflag & ~lt->c_lflag);
2049 		for (cc = 0; cc < NCCS; ++cc)
2050 			if (lt->c_cc[cc] != 0)
2051 				dt->c_cc[cc] = tp->t_cc[cc];
2052 		if (lt->c_ispeed != 0)
2053 			dt->c_ispeed = tp->t_ispeed;
2054 		if (lt->c_ospeed != 0)
2055 			dt->c_ospeed = tp->t_ospeed;
2056 	}
2057 	error = (*linesw[tp->t_line].l_ioctl)(tp, ap->a_cmd, data, ap->a_fflag, ap->a_cred);
2058 	if (error != ENOIOCTL)
2059 		return (error);
2060 	crit_enter();
2061 	error = ttioctl(tp, ap->a_cmd, data, ap->a_fflag);
2062 	disc_optim(tp, &tp->t_termios, com);
2063 	if (error != ENOIOCTL) {
2064 		crit_exit();
2065 		return (error);
2066 	}
2067 	switch (ap->a_cmd) {
2068 	case TIOCSBRK:
2069 		sio_setreg(com, com_cfcr, com->cfcr_image |= CFCR_SBREAK);
2070 		break;
2071 	case TIOCCBRK:
2072 		sio_setreg(com, com_cfcr, com->cfcr_image &= ~CFCR_SBREAK);
2073 		break;
2074 	case TIOCSDTR:
2075 		(void)commctl(com, TIOCM_DTR, DMBIS);
2076 		break;
2077 	case TIOCCDTR:
2078 		(void)commctl(com, TIOCM_DTR, DMBIC);
2079 		break;
2080 	/*
2081 	 * XXX should disallow changing MCR_RTS if CS_RTS_IFLOW is set.  The
2082 	 * changes get undone on the next call to comparam().
2083 	 */
2084 	case TIOCMSET:
2085 		(void)commctl(com, *(int *)data, DMSET);
2086 		break;
2087 	case TIOCMBIS:
2088 		(void)commctl(com, *(int *)data, DMBIS);
2089 		break;
2090 	case TIOCMBIC:
2091 		(void)commctl(com, *(int *)data, DMBIC);
2092 		break;
2093 	case TIOCMGET:
2094 		*(int *)data = commctl(com, 0, DMGET);
2095 		break;
2096 	case TIOCMSDTRWAIT:
2097 		/* must be root since the wait applies to following logins */
2098 		error = suser_cred(ap->a_cred, 0);
2099 		if (error != 0) {
2100 			crit_exit();
2101 			return (error);
2102 		}
2103 		com->dtr_wait = *(int *)data * hz / 100;
2104 		break;
2105 	case TIOCMGDTRWAIT:
2106 		*(int *)data = com->dtr_wait * 100 / hz;
2107 		break;
2108 	case TIOCTIMESTAMP:
2109 		com->do_timestamp = TRUE;
2110 		*(struct timeval *)data = com->timestamp;
2111 		break;
2112 	case TIOCDCDTIMESTAMP:
2113 		com->do_dcd_timestamp = TRUE;
2114 		*(struct timeval *)data = com->dcd_timestamp;
2115 		break;
2116 	default:
2117 		crit_exit();
2118 		error = pps_ioctl(ap->a_cmd, data, &com->pps);
2119 		if (error == ENODEV)
2120 			error = ENOTTY;
2121 		return (error);
2122 	}
2123 	crit_exit();
2124 	return (0);
2125 }
2126 
2127 static void
2128 siopoll(void *dummy, void *frame)
2129 {
2130 	int		unit;
2131 
2132 	if (com_events == 0)
2133 		return;
2134 repeat:
2135 	for (unit = 0; unit < sio_numunits; ++unit) {
2136 		struct com_s	*com;
2137 		int		incc;
2138 		struct tty	*tp;
2139 
2140 		com = com_addr(unit);
2141 		if (com == NULL)
2142 			continue;
2143 		tp = com->tp;
2144 		if (tp == NULL || com->gone) {
2145 			/*
2146 			 * Discard any events related to never-opened or
2147 			 * going-away devices.
2148 			 */
2149 			com_lock();
2150 			incc = com->iptr - com->ibuf;
2151 			com->iptr = com->ibuf;
2152 			if (com->state & CS_CHECKMSR) {
2153 				incc += LOTS_OF_EVENTS;
2154 				com->state &= ~CS_CHECKMSR;
2155 			}
2156 			com_events -= incc;
2157 			com_unlock();
2158 			continue;
2159 		}
2160 		if (com->iptr != com->ibuf) {
2161 			com_lock();
2162 			sioinput(com);
2163 			com_unlock();
2164 		}
2165 		if (com->state & CS_CHECKMSR) {
2166 			u_char	delta_modem_status;
2167 
2168 			com_lock();
2169 			delta_modem_status = com->last_modem_status
2170 					     ^ com->prev_modem_status;
2171 			com->prev_modem_status = com->last_modem_status;
2172 			com_events -= LOTS_OF_EVENTS;
2173 			com->state &= ~CS_CHECKMSR;
2174 			com_unlock();
2175 			if (delta_modem_status & MSR_DCD)
2176 				(*linesw[tp->t_line].l_modem)
2177 					(tp, com->prev_modem_status & MSR_DCD);
2178 		}
2179 		if (com->state & CS_ODONE) {
2180 			com_lock();
2181 			com_events -= LOTS_OF_EVENTS;
2182 			com->state &= ~CS_ODONE;
2183 			com_unlock();
2184 			if (!(com->state & CS_BUSY)
2185 			    && !(com->extra_state & CSE_BUSYCHECK)) {
2186 				callout_reset(&com->busy_ch, hz / 100,
2187 						siobusycheck, com);
2188 				com->extra_state |= CSE_BUSYCHECK;
2189 			}
2190 			(*linesw[tp->t_line].l_start)(tp);
2191 		}
2192 		if (com_events == 0)
2193 			break;
2194 	}
2195 	if (com_events >= LOTS_OF_EVENTS)
2196 		goto repeat;
2197 }
2198 
2199 static int
2200 comparam(tp, t)
2201 	struct tty	*tp;
2202 	struct termios	*t;
2203 {
2204 	u_int		cfcr;
2205 	int		cflag;
2206 	struct com_s	*com;
2207 	u_int		divisor;
2208 	u_char		dlbh;
2209 	u_char		dlbl;
2210 	int		unit;
2211 
2212 	unit = DEV_TO_UNIT(tp->t_dev);
2213 	com = com_addr(unit);
2214 	if (com == NULL)
2215 		return (ENODEV);
2216 
2217 	/* do historical conversions */
2218 	if (t->c_ispeed == 0)
2219 		t->c_ispeed = t->c_ospeed;
2220 
2221 	/* check requested parameters */
2222 	if (t->c_ospeed == 0)
2223 		divisor = 0;
2224 	else {
2225 		if (t->c_ispeed != t->c_ospeed)
2226 			return (EINVAL);
2227 		divisor = siodivisor(com->rclk, t->c_ispeed);
2228 		if (divisor == 0)
2229 			return (EINVAL);
2230 	}
2231 
2232 	/* parameters are OK, convert them to the com struct and the device */
2233 	crit_enter();
2234 	if (divisor == 0)
2235 		(void)commctl(com, TIOCM_DTR, DMBIC);	/* hang up line */
2236 	else
2237 		(void)commctl(com, TIOCM_DTR, DMBIS);
2238 	cflag = t->c_cflag;
2239 	switch (cflag & CSIZE) {
2240 	case CS5:
2241 		cfcr = CFCR_5BITS;
2242 		break;
2243 	case CS6:
2244 		cfcr = CFCR_6BITS;
2245 		break;
2246 	case CS7:
2247 		cfcr = CFCR_7BITS;
2248 		break;
2249 	default:
2250 		cfcr = CFCR_8BITS;
2251 		break;
2252 	}
2253 	if (cflag & PARENB) {
2254 		cfcr |= CFCR_PENAB;
2255 		if (!(cflag & PARODD))
2256 			cfcr |= CFCR_PEVEN;
2257 	}
2258 	if (cflag & CSTOPB)
2259 		cfcr |= CFCR_STOPB;
2260 
2261 	if (com->hasfifo && divisor != 0) {
2262 		/*
2263 		 * Use a fifo trigger level low enough so that the input
2264 		 * latency from the fifo is less than about 16 msec and
2265 		 * the total latency is less than about 30 msec.  These
2266 		 * latencies are reasonable for humans.  Serial comms
2267 		 * protocols shouldn't expect anything better since modem
2268 		 * latencies are larger.
2269 		 *
2270 		 * Interrupts can be held up for long periods of time
2271 		 * due to inefficiencies in other parts of the kernel,
2272 		 * certain video cards, etc.  Setting the FIFO trigger
2273 		 * point to MEDH instead of HIGH gives us 694uS of slop
2274 		 * (8 character times) instead of 173uS (2 character times)
2275 		 * @ 115200 bps.
2276 		 */
2277 		com->fifo_image = t->c_ospeed <= 4800
2278 				  ? FIFO_ENABLE : FIFO_ENABLE | FIFO_RX_MEDH;
2279 #ifdef COM_ESP
2280 		/*
2281 		 * The Hayes ESP card needs the fifo DMA mode bit set
2282 		 * in compatibility mode.  If not, it will interrupt
2283 		 * for each character received.
2284 		 */
2285 		if (com->esp)
2286 			com->fifo_image |= FIFO_DMA_MODE;
2287 #endif
2288 		sio_setreg(com, com_fifo, com->fifo_image);
2289 	}
2290 
2291 	/*
2292 	 * This returns with interrupts disabled so that we can complete
2293 	 * the speed change atomically.  Keeping interrupts disabled is
2294 	 * especially important while com_data is hidden.
2295 	 */
2296 	(void) siosetwater(com, t->c_ispeed);
2297 
2298 	if (divisor != 0) {
2299 		sio_setreg(com, com_cfcr, cfcr | CFCR_DLAB);
2300 		/*
2301 		 * Only set the divisor registers if they would change,
2302 		 * since on some 16550 incompatibles (UMC8669F), setting
2303 		 * them while input is arriving them loses sync until
2304 		 * data stops arriving.
2305 		 */
2306 		dlbl = divisor & 0xFF;
2307 		if (sio_getreg(com, com_dlbl) != dlbl)
2308 			sio_setreg(com, com_dlbl, dlbl);
2309 		dlbh = divisor >> 8;
2310 		if (sio_getreg(com, com_dlbh) != dlbh)
2311 			sio_setreg(com, com_dlbh, dlbh);
2312 	}
2313 
2314 	sio_setreg(com, com_cfcr, com->cfcr_image = cfcr);
2315 
2316 	if (!(tp->t_state & TS_TTSTOP))
2317 		com->state |= CS_TTGO;
2318 
2319 	if (cflag & CRTS_IFLOW) {
2320 		if (com->st16650a) {
2321 			sio_setreg(com, com_cfcr, 0xbf);
2322 			sio_setreg(com, com_fifo,
2323 				   sio_getreg(com, com_fifo) | 0x40);
2324 		}
2325 		com->state |= CS_RTS_IFLOW;
2326 		/*
2327 		 * If CS_RTS_IFLOW just changed from off to on, the change
2328 		 * needs to be propagated to MCR_RTS.  This isn't urgent,
2329 		 * so do it later by calling comstart() instead of repeating
2330 		 * a lot of code from comstart() here.
2331 		 */
2332 	} else if (com->state & CS_RTS_IFLOW) {
2333 		com->state &= ~CS_RTS_IFLOW;
2334 		/*
2335 		 * CS_RTS_IFLOW just changed from on to off.  Force MCR_RTS
2336 		 * on here, since comstart() won't do it later.
2337 		 */
2338 		outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
2339 		if (com->st16650a) {
2340 			sio_setreg(com, com_cfcr, 0xbf);
2341 			sio_setreg(com, com_fifo,
2342 				   sio_getreg(com, com_fifo) & ~0x40);
2343 		}
2344 	}
2345 
2346 
2347 	/*
2348 	 * Set up state to handle output flow control.
2349 	 * XXX - worth handling MDMBUF (DCD) flow control at the lowest level?
2350 	 * Now has 10+ msec latency, while CTS flow has 50- usec latency.
2351 	 */
2352 	com->state |= CS_ODEVREADY;
2353 	com->state &= ~CS_CTS_OFLOW;
2354 	if (cflag & CCTS_OFLOW) {
2355 		com->state |= CS_CTS_OFLOW;
2356 		if (!(com->last_modem_status & MSR_CTS))
2357 			com->state &= ~CS_ODEVREADY;
2358 		if (com->st16650a) {
2359 			sio_setreg(com, com_cfcr, 0xbf);
2360 			sio_setreg(com, com_fifo,
2361 				   sio_getreg(com, com_fifo) | 0x80);
2362 		}
2363 	} else {
2364 		if (com->st16650a) {
2365 			sio_setreg(com, com_cfcr, 0xbf);
2366 			sio_setreg(com, com_fifo,
2367 				   sio_getreg(com, com_fifo) & ~0x80);
2368 		}
2369 	}
2370 
2371 	sio_setreg(com, com_cfcr, com->cfcr_image);
2372 
2373 	/* XXX shouldn't call functions while intrs are disabled. */
2374 	disc_optim(tp, t, com);
2375 	/*
2376 	 * Recover from fiddling with CS_TTGO.  We used to call siointr1()
2377 	 * unconditionally, but that defeated the careful discarding of
2378 	 * stale input in sioopen().
2379 	 */
2380 	if (com->state >= (CS_BUSY | CS_TTGO))
2381 		siointr1(com);
2382 
2383 	com_unlock();
2384 	crit_exit();
2385 	comstart(tp);
2386 	if (com->ibufold != NULL) {
2387 		kfree(com->ibufold, M_DEVBUF);
2388 		com->ibufold = NULL;
2389 	}
2390 	return (0);
2391 }
2392 
2393 static int
2394 siosetwater(com, speed)
2395 	struct com_s	*com;
2396 	speed_t		speed;
2397 {
2398 	int		cp4ticks;
2399 	u_char		*ibuf;
2400 	int		ibufsize;
2401 	struct tty	*tp;
2402 
2403 	/*
2404 	 * Make the buffer size large enough to handle a softtty interrupt
2405 	 * latency of about 2 ticks without loss of throughput or data
2406 	 * (about 3 ticks if input flow control is not used or not honoured,
2407 	 * but a bit less for CS5-CS7 modes).
2408 	 */
2409 	cp4ticks = speed / 10 / hz * 4;
2410 	for (ibufsize = 128; ibufsize < cp4ticks;)
2411 		ibufsize <<= 1;
2412 	if (ibufsize == com->ibufsize) {
2413 		com_lock();
2414 		return (0);
2415 	}
2416 
2417 	/*
2418 	 * Allocate input buffer.  The extra factor of 2 in the size is
2419 	 * to allow for an error byte for each input byte.
2420 	 */
2421 	ibuf = kmalloc(2 * ibufsize, M_DEVBUF, M_WAITOK | M_ZERO);
2422 
2423 	/* Initialize non-critical variables. */
2424 	com->ibufold = com->ibuf;
2425 	com->ibufsize = ibufsize;
2426 	tp = com->tp;
2427 	if (tp != NULL) {
2428 		tp->t_ififosize = 2 * ibufsize;
2429 		tp->t_ispeedwat = (speed_t)-1;
2430 		tp->t_ospeedwat = (speed_t)-1;
2431 	}
2432 
2433 	/*
2434 	 * Read current input buffer, if any.  Continue with interrupts
2435 	 * disabled.
2436 	 */
2437 	com_lock();
2438 	if (com->iptr != com->ibuf)
2439 		sioinput(com);
2440 
2441 	/*-
2442 	 * Initialize critical variables, including input buffer watermarks.
2443 	 * The external device is asked to stop sending when the buffer
2444 	 * exactly reaches high water, or when the high level requests it.
2445 	 * The high level is notified immediately (rather than at a later
2446 	 * clock tick) when this watermark is reached.
2447 	 * The buffer size is chosen so the watermark should almost never
2448 	 * be reached.
2449 	 * The low watermark is invisibly 0 since the buffer is always
2450 	 * emptied all at once.
2451 	 */
2452 	com->iptr = com->ibuf = ibuf;
2453 	com->ibufend = ibuf + ibufsize;
2454 	com->ierroff = ibufsize;
2455 	com->ihighwater = ibuf + 3 * ibufsize / 4;
2456 	return (0);
2457 }
2458 
2459 static void
2460 comstart(tp)
2461 	struct tty	*tp;
2462 {
2463 	struct com_s	*com;
2464 	int		unit;
2465 
2466 	unit = DEV_TO_UNIT(tp->t_dev);
2467 	com = com_addr(unit);
2468 	if (com == NULL)
2469 		return;
2470 	crit_enter();
2471 	com_lock();
2472 	if (tp->t_state & TS_TTSTOP)
2473 		com->state &= ~CS_TTGO;
2474 	else
2475 		com->state |= CS_TTGO;
2476 	if (tp->t_state & TS_TBLOCK) {
2477 		if (com->mcr_image & MCR_RTS && com->state & CS_RTS_IFLOW)
2478 			outb(com->modem_ctl_port, com->mcr_image &= ~MCR_RTS);
2479 	} else {
2480 		if (!(com->mcr_image & MCR_RTS) && com->iptr < com->ihighwater
2481 		    && com->state & CS_RTS_IFLOW)
2482 			outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
2483 	}
2484 	com_unlock();
2485 	if (tp->t_state & (TS_TIMEOUT | TS_TTSTOP)) {
2486 		ttwwakeup(tp);
2487 		crit_exit();
2488 		return;
2489 	}
2490 	if (tp->t_outq.c_cc != 0) {
2491 		struct lbq	*qp;
2492 		struct lbq	*next;
2493 
2494 		if (!com->obufs[0].l_queued) {
2495 			com->obufs[0].l_tail
2496 			    = com->obuf1 + q_to_b(&tp->t_outq, com->obuf1,
2497 						  sizeof com->obuf1);
2498 			com->obufs[0].l_next = NULL;
2499 			com->obufs[0].l_queued = TRUE;
2500 			com_lock();
2501 			if (com->state & CS_BUSY) {
2502 				qp = com->obufq.l_next;
2503 				while ((next = qp->l_next) != NULL)
2504 					qp = next;
2505 				qp->l_next = &com->obufs[0];
2506 			} else {
2507 				com->obufq.l_head = com->obufs[0].l_head;
2508 				com->obufq.l_tail = com->obufs[0].l_tail;
2509 				com->obufq.l_next = &com->obufs[0];
2510 				com->state |= CS_BUSY;
2511 			}
2512 			com_unlock();
2513 		}
2514 		if (tp->t_outq.c_cc != 0 && !com->obufs[1].l_queued) {
2515 			com->obufs[1].l_tail
2516 			    = com->obuf2 + q_to_b(&tp->t_outq, com->obuf2,
2517 						  sizeof com->obuf2);
2518 			com->obufs[1].l_next = NULL;
2519 			com->obufs[1].l_queued = TRUE;
2520 			com_lock();
2521 			if (com->state & CS_BUSY) {
2522 				qp = com->obufq.l_next;
2523 				while ((next = qp->l_next) != NULL)
2524 					qp = next;
2525 				qp->l_next = &com->obufs[1];
2526 			} else {
2527 				com->obufq.l_head = com->obufs[1].l_head;
2528 				com->obufq.l_tail = com->obufs[1].l_tail;
2529 				com->obufq.l_next = &com->obufs[1];
2530 				com->state |= CS_BUSY;
2531 			}
2532 			com_unlock();
2533 		}
2534 		tp->t_state |= TS_BUSY;
2535 	}
2536 	com_lock();
2537 	if (com->state >= (CS_BUSY | CS_TTGO))
2538 		siointr1(com);	/* fake interrupt to start output */
2539 	com_unlock();
2540 	ttwwakeup(tp);
2541 	crit_exit();
2542 }
2543 
2544 static void
2545 comstop(tp, rw)
2546 	struct tty	*tp;
2547 	int		rw;
2548 {
2549 	struct com_s	*com;
2550 
2551 	com = com_addr(DEV_TO_UNIT(tp->t_dev));
2552 	if (com == NULL || com->gone)
2553 		return;
2554 	com_lock();
2555 	if (rw & FWRITE) {
2556 		if (com->hasfifo)
2557 #ifdef COM_ESP
2558 		    /* XXX avoid h/w bug. */
2559 		    if (!com->esp)
2560 #endif
2561 			sio_setreg(com, com_fifo,
2562 				   FIFO_XMT_RST | com->fifo_image);
2563 		com->obufs[0].l_queued = FALSE;
2564 		com->obufs[1].l_queued = FALSE;
2565 		if (com->state & CS_ODONE)
2566 			com_events -= LOTS_OF_EVENTS;
2567 		com->state &= ~(CS_ODONE | CS_BUSY);
2568 		com->tp->t_state &= ~TS_BUSY;
2569 	}
2570 	if (rw & FREAD) {
2571 		if (com->hasfifo)
2572 #ifdef COM_ESP
2573 		    /* XXX avoid h/w bug. */
2574 		    if (!com->esp)
2575 #endif
2576 			sio_setreg(com, com_fifo,
2577 				   FIFO_RCV_RST | com->fifo_image);
2578 		com_events -= (com->iptr - com->ibuf);
2579 		com->iptr = com->ibuf;
2580 	}
2581 	com_unlock();
2582 	comstart(tp);
2583 }
2584 
2585 static int
2586 commctl(com, bits, how)
2587 	struct com_s	*com;
2588 	int		bits;
2589 	int		how;
2590 {
2591 	int	mcr;
2592 	int	msr;
2593 
2594 	if (how == DMGET) {
2595 		bits = TIOCM_LE;	/* XXX - always enabled while open */
2596 		mcr = com->mcr_image;
2597 		if (mcr & MCR_DTR)
2598 			bits |= TIOCM_DTR;
2599 		if (mcr & MCR_RTS)
2600 			bits |= TIOCM_RTS;
2601 		msr = com->prev_modem_status;
2602 		if (msr & MSR_CTS)
2603 			bits |= TIOCM_CTS;
2604 		if (msr & MSR_DCD)
2605 			bits |= TIOCM_CD;
2606 		if (msr & MSR_DSR)
2607 			bits |= TIOCM_DSR;
2608 		/*
2609 		 * XXX - MSR_RI is naturally volatile, and we make MSR_TERI
2610 		 * more volatile by reading the modem status a lot.  Perhaps
2611 		 * we should latch both bits until the status is read here.
2612 		 */
2613 		if (msr & (MSR_RI | MSR_TERI))
2614 			bits |= TIOCM_RI;
2615 		return (bits);
2616 	}
2617 	mcr = 0;
2618 	if (bits & TIOCM_DTR)
2619 		mcr |= MCR_DTR;
2620 	if (bits & TIOCM_RTS)
2621 		mcr |= MCR_RTS;
2622 	if (com->gone)
2623 		return(0);
2624 	com_lock();
2625 	switch (how) {
2626 	case DMSET:
2627 		outb(com->modem_ctl_port,
2628 		     com->mcr_image = mcr | (com->mcr_image & MCR_IENABLE));
2629 		break;
2630 	case DMBIS:
2631 		outb(com->modem_ctl_port, com->mcr_image |= mcr);
2632 		break;
2633 	case DMBIC:
2634 		outb(com->modem_ctl_port, com->mcr_image &= ~mcr);
2635 		break;
2636 	}
2637 	com_unlock();
2638 	return (0);
2639 }
2640 
2641 static void
2642 siosettimeout()
2643 {
2644 	struct com_s	*com;
2645 	bool_t		someopen;
2646 	int		unit;
2647 
2648 	/*
2649 	 * Set our timeout period to 1 second if no polled devices are open.
2650 	 * Otherwise set it to max(1/200, 1/hz).
2651 	 * Enable timeouts iff some device is open.
2652 	 */
2653 	callout_stop(&sio_timeout_handle);
2654 	sio_timeout = hz;
2655 	someopen = FALSE;
2656 	for (unit = 0; unit < sio_numunits; ++unit) {
2657 		com = com_addr(unit);
2658 		if (com != NULL && com->tp != NULL
2659 		    && com->tp->t_state & TS_ISOPEN && !com->gone) {
2660 			someopen = TRUE;
2661 			if (com->poll || com->poll_output) {
2662 				sio_timeout = hz > 200 ? hz / 200 : 1;
2663 				break;
2664 			}
2665 		}
2666 	}
2667 	if (someopen) {
2668 		sio_timeouts_until_log = hz / sio_timeout;
2669 		callout_reset(&sio_timeout_handle, sio_timeout,
2670 				comwakeup, NULL);
2671 	} else {
2672 		/* Flush error messages, if any. */
2673 		sio_timeouts_until_log = 1;
2674 		comwakeup((void *)NULL);
2675 		callout_stop(&sio_timeout_handle);
2676 	}
2677 }
2678 
2679 static void
2680 comwakeup(chan)
2681 	void	*chan;
2682 {
2683 	struct com_s	*com;
2684 	int		unit;
2685 
2686 	callout_reset(&sio_timeout_handle, sio_timeout, comwakeup, NULL);
2687 
2688 	/*
2689 	 * Recover from lost output interrupts.
2690 	 * Poll any lines that don't use interrupts.
2691 	 */
2692 	for (unit = 0; unit < sio_numunits; ++unit) {
2693 		com = com_addr(unit);
2694 		if (com != NULL && !com->gone
2695 		    && (com->state >= (CS_BUSY | CS_TTGO) || com->poll)) {
2696 			com_lock();
2697 			siointr1(com);
2698 			com_unlock();
2699 		}
2700 	}
2701 
2702 	/*
2703 	 * Check for and log errors, but not too often.
2704 	 */
2705 	if (--sio_timeouts_until_log > 0)
2706 		return;
2707 	sio_timeouts_until_log = hz / sio_timeout;
2708 	for (unit = 0; unit < sio_numunits; ++unit) {
2709 		int	errnum;
2710 
2711 		com = com_addr(unit);
2712 		if (com == NULL)
2713 			continue;
2714 		if (com->gone)
2715 			continue;
2716 		for (errnum = 0; errnum < CE_NTYPES; ++errnum) {
2717 			u_int	delta;
2718 			u_long	total;
2719 
2720 			com_lock();
2721 			delta = com->delta_error_counts[errnum];
2722 			com->delta_error_counts[errnum] = 0;
2723 			com_unlock();
2724 			if (delta == 0)
2725 				continue;
2726 			total = com->error_counts[errnum] += delta;
2727 			log(LOG_ERR, "sio%d: %u more %s%s (total %lu)\n",
2728 			    unit, delta, error_desc[errnum],
2729 			    delta == 1 ? "" : "s", total);
2730 		}
2731 	}
2732 }
2733 
2734 static void
2735 disc_optim(tp, t, com)
2736 	struct tty	*tp;
2737 	struct termios	*t;
2738 	struct com_s	*com;
2739 {
2740 	if (!(t->c_iflag & (ICRNL | IGNCR | IMAXBEL | INLCR | ISTRIP | IXON))
2741 	    && (!(t->c_iflag & BRKINT) || (t->c_iflag & IGNBRK))
2742 	    && (!(t->c_iflag & PARMRK)
2743 		|| (t->c_iflag & (IGNPAR | IGNBRK)) == (IGNPAR | IGNBRK))
2744 	    && !(t->c_lflag & (ECHO | ICANON | IEXTEN | ISIG | PENDIN))
2745 	    && linesw[tp->t_line].l_rint == ttyinput)
2746 		tp->t_state |= TS_CAN_BYPASS_L_RINT;
2747 	else
2748 		tp->t_state &= ~TS_CAN_BYPASS_L_RINT;
2749 	com->hotchar = linesw[tp->t_line].l_hotchar;
2750 }
2751 
2752 /*
2753  * Following are all routines needed for SIO to act as console
2754  */
2755 #include <sys/cons.h>
2756 
2757 struct siocnstate {
2758 	u_char	dlbl;
2759 	u_char	dlbh;
2760 	u_char	ier;
2761 	u_char	cfcr;
2762 	u_char	mcr;
2763 };
2764 
2765 static speed_t siocngetspeed (Port_t, u_long rclk);
2766 static void siocnclose	(struct siocnstate *sp, Port_t iobase);
2767 static void siocnopen	(struct siocnstate *sp, Port_t iobase, int speed);
2768 static void siocntxwait	(Port_t iobase);
2769 
2770 static cn_probe_t siocnprobe;
2771 static cn_init_t siocninit;
2772 static cn_checkc_t siocncheckc;
2773 static cn_getc_t siocngetc;
2774 static cn_putc_t siocnputc;
2775 
2776 #ifdef __i386__
2777 CONS_DRIVER(sio, siocnprobe, siocninit, NULL, siocngetc, siocncheckc,
2778 	    siocnputc, NULL);
2779 #endif
2780 
2781 /* To get the GDB related variables */
2782 #if DDB > 0
2783 #include <ddb/ddb.h>
2784 #endif
2785 
2786 static void
2787 siocntxwait(iobase)
2788 	Port_t	iobase;
2789 {
2790 	int	timo;
2791 
2792 	/*
2793 	 * Wait for any pending transmission to finish.  Required to avoid
2794 	 * the UART lockup bug when the speed is changed, and for normal
2795 	 * transmits.
2796 	 */
2797 	timo = 100000;
2798 	while ((inb(iobase + com_lsr) & (LSR_TSRE | LSR_TXRDY))
2799 	       != (LSR_TSRE | LSR_TXRDY) && --timo != 0)
2800 		;
2801 }
2802 
2803 /*
2804  * Read the serial port specified and try to figure out what speed
2805  * it's currently running at.  We're assuming the serial port has
2806  * been initialized and is basicly idle.  This routine is only intended
2807  * to be run at system startup.
2808  *
2809  * If the value read from the serial port doesn't make sense, return 0.
2810  */
2811 
2812 static speed_t
2813 siocngetspeed(iobase, rclk)
2814 	Port_t	iobase;
2815 	u_long	rclk;
2816 {
2817 	u_int	divisor;
2818 	u_char	dlbh;
2819 	u_char	dlbl;
2820 	u_char  cfcr;
2821 
2822 	cfcr = inb(iobase + com_cfcr);
2823 	outb(iobase + com_cfcr, CFCR_DLAB | cfcr);
2824 
2825 	dlbl = inb(iobase + com_dlbl);
2826 	dlbh = inb(iobase + com_dlbh);
2827 
2828 	outb(iobase + com_cfcr, cfcr);
2829 
2830 	divisor = dlbh << 8 | dlbl;
2831 
2832 	/* XXX there should be more sanity checking. */
2833 	if (divisor == 0)
2834 		return (CONSPEED);
2835 	return (rclk / (16UL * divisor));
2836 }
2837 
2838 static void
2839 siocnopen(sp, iobase, speed)
2840 	struct siocnstate	*sp;
2841 	Port_t			iobase;
2842 	int			speed;
2843 {
2844 	u_int	divisor;
2845 	u_char	dlbh;
2846 	u_char	dlbl;
2847 
2848 	/*
2849 	 * Save all the device control registers except the fifo register
2850 	 * and set our default ones (cs8 -parenb speed=comdefaultrate).
2851 	 * We can't save the fifo register since it is read-only.
2852 	 */
2853 	sp->ier = inb(iobase + com_ier);
2854 	outb(iobase + com_ier, 0);	/* spltty() doesn't stop siointr() */
2855 	siocntxwait(iobase);
2856 	sp->cfcr = inb(iobase + com_cfcr);
2857 	outb(iobase + com_cfcr, CFCR_DLAB | CFCR_8BITS);
2858 	sp->dlbl = inb(iobase + com_dlbl);
2859 	sp->dlbh = inb(iobase + com_dlbh);
2860 	/*
2861 	 * Only set the divisor registers if they would change, since on
2862 	 * some 16550 incompatibles (Startech), setting them clears the
2863 	 * data input register.  This also reduces the effects of the
2864 	 * UMC8669F bug.
2865 	 */
2866 	divisor = siodivisor(comdefaultrclk, speed);
2867 	dlbl = divisor & 0xFF;
2868 	if (sp->dlbl != dlbl)
2869 		outb(iobase + com_dlbl, dlbl);
2870 	dlbh = divisor >> 8;
2871 	if (sp->dlbh != dlbh)
2872 		outb(iobase + com_dlbh, dlbh);
2873 	outb(iobase + com_cfcr, CFCR_8BITS);
2874 	sp->mcr = inb(iobase + com_mcr);
2875 	/*
2876 	 * We don't want interrupts, but must be careful not to "disable"
2877 	 * them by clearing the MCR_IENABLE bit, since that might cause
2878 	 * an interrupt by floating the IRQ line.
2879 	 */
2880 	outb(iobase + com_mcr, (sp->mcr & MCR_IENABLE) | MCR_DTR | MCR_RTS);
2881 }
2882 
2883 static void
2884 siocnclose(sp, iobase)
2885 	struct siocnstate	*sp;
2886 	Port_t			iobase;
2887 {
2888 	/*
2889 	 * Restore the device control registers.
2890 	 */
2891 	siocntxwait(iobase);
2892 	outb(iobase + com_cfcr, CFCR_DLAB | CFCR_8BITS);
2893 	if (sp->dlbl != inb(iobase + com_dlbl))
2894 		outb(iobase + com_dlbl, sp->dlbl);
2895 	if (sp->dlbh != inb(iobase + com_dlbh))
2896 		outb(iobase + com_dlbh, sp->dlbh);
2897 	outb(iobase + com_cfcr, sp->cfcr);
2898 	/*
2899 	 * XXX damp oscillations of MCR_DTR and MCR_RTS by not restoring them.
2900 	 */
2901 	outb(iobase + com_mcr, sp->mcr | MCR_DTR | MCR_RTS);
2902 	outb(iobase + com_ier, sp->ier);
2903 }
2904 
2905 static void
2906 siocnprobe(cp)
2907 	struct consdev	*cp;
2908 {
2909 	speed_t			boot_speed;
2910 	u_char			cfcr;
2911 	u_int			divisor;
2912 	int			unit;
2913 	struct siocnstate	sp;
2914 
2915 	/*
2916 	 * Find our first enabled console, if any.  If it is a high-level
2917 	 * console device, then initialize it and return successfully.
2918 	 * If it is a low-level console device, then initialize it and
2919 	 * return unsuccessfully.  It must be initialized in both cases
2920 	 * for early use by console drivers and debuggers.  Initializing
2921 	 * the hardware is not necessary in all cases, since the i/o
2922 	 * routines initialize it on the fly, but it is necessary if
2923 	 * input might arrive while the hardware is switched back to an
2924 	 * uninitialized state.  We can't handle multiple console devices
2925 	 * yet because our low-level routines don't take a device arg.
2926 	 * We trust the user to set the console flags properly so that we
2927 	 * don't need to probe.
2928 	 */
2929 	cp->cn_pri = CN_DEAD;
2930 
2931 	for (unit = 0; unit < 16; unit++) { /* XXX need to know how many */
2932 		int flags;
2933 		int disabled;
2934 		if (resource_int_value("sio", unit, "disabled", &disabled) == 0) {
2935 			if (disabled)
2936 				continue;
2937 		}
2938 		if (resource_int_value("sio", unit, "flags", &flags))
2939 			continue;
2940 		if (COM_CONSOLE(flags) || COM_DEBUGGER(flags)) {
2941 			int port;
2942 			Port_t iobase;
2943 
2944 			if (resource_int_value("sio", unit, "port", &port))
2945 				continue;
2946 			iobase = port;
2947 			crit_enter();
2948 			if (boothowto & RB_SERIAL) {
2949 				boot_speed =
2950 				    siocngetspeed(iobase, comdefaultrclk);
2951 				if (boot_speed)
2952 					comdefaultrate = boot_speed;
2953 			}
2954 
2955 			/*
2956 			 * Initialize the divisor latch.  We can't rely on
2957 			 * siocnopen() to do this the first time, since it
2958 			 * avoids writing to the latch if the latch appears
2959 			 * to have the correct value.  Also, if we didn't
2960 			 * just read the speed from the hardware, then we
2961 			 * need to set the speed in hardware so that
2962 			 * switching it later is null.
2963 			 */
2964 			cfcr = inb(iobase + com_cfcr);
2965 			outb(iobase + com_cfcr, CFCR_DLAB | cfcr);
2966 			divisor = siodivisor(comdefaultrclk, comdefaultrate);
2967 			outb(iobase + com_dlbl, divisor & 0xff);
2968 			outb(iobase + com_dlbh, divisor >> 8);
2969 			outb(iobase + com_cfcr, cfcr);
2970 
2971 			siocnopen(&sp, iobase, comdefaultrate);
2972 
2973 			crit_exit();
2974 			if (COM_CONSOLE(flags) && !COM_LLCONSOLE(flags)) {
2975 				cp->cn_dev = make_dev(&sio_ops, unit,
2976 						UID_ROOT, GID_WHEEL, 0600,
2977 						"ttyd%r", unit);
2978 				cp->cn_pri = COM_FORCECONSOLE(flags)
2979 					     || boothowto & RB_SERIAL
2980 					     ? CN_REMOTE : CN_NORMAL;
2981 				siocniobase = iobase;
2982 				siocnunit = unit;
2983 			}
2984 			if (COM_DEBUGGER(flags)) {
2985 				printf("sio%d: gdb debugging port\n", unit);
2986 				siogdbiobase = iobase;
2987 				siogdbunit = unit;
2988 #if DDB > 0
2989 				gdbdev = make_dev(&sio_ops, unit,
2990 						UID_ROOT, GID_WHEEL, 0600,
2991 						"ttyd%r", unit);
2992 				gdb_getc = siocngetc;
2993 				gdb_putc = siocnputc;
2994 #endif
2995 			}
2996 		}
2997 	}
2998 #ifdef	__i386__
2999 #if DDB > 0
3000 	/*
3001 	 * XXX Ugly Compatability.
3002 	 * If no gdb port has been specified, set it to be the console
3003 	 * as some configuration files don't specify the gdb port.
3004 	 */
3005 	if (gdbdev == NOCDEV && (boothowto & RB_GDB)) {
3006 		printf("Warning: no GDB port specified. Defaulting to sio%d.\n",
3007 			siocnunit);
3008 		printf("Set flag 0x80 on desired GDB port in your\n");
3009 		printf("configuration file (currently sio only).\n");
3010 		siogdbiobase = siocniobase;
3011 		siogdbunit = siocnunit;
3012 		gdbdev = make_dev(&sio_ops, siocnunit,
3013 				UID_ROOT, GID_WHEEL, 0600,
3014 				"ttyd%r", siocnunit);
3015 		gdb_getc = siocngetc;
3016 		gdb_putc = siocnputc;
3017 	}
3018 #endif
3019 #endif
3020 }
3021 
3022 static void
3023 siocninit(cp)
3024 	struct consdev	*cp;
3025 {
3026 	comconsole = DEV_TO_UNIT(cp->cn_dev);
3027 }
3028 
3029 static int
3030 siocncheckc(dev)
3031 	cdev_t	dev;
3032 {
3033 	int	c;
3034 	Port_t	iobase;
3035 	struct siocnstate	sp;
3036 
3037 	if (minor(dev) == siogdbunit)
3038 		iobase = siogdbiobase;
3039 	else
3040 		iobase = siocniobase;
3041 	crit_enter();
3042 	siocnopen(&sp, iobase, comdefaultrate);
3043 	if (inb(iobase + com_lsr) & LSR_RXRDY)
3044 		c = inb(iobase + com_data);
3045 	else
3046 		c = -1;
3047 	siocnclose(&sp, iobase);
3048 	crit_exit();
3049 	return (c);
3050 }
3051 
3052 
3053 int
3054 siocngetc(dev)
3055 	cdev_t	dev;
3056 {
3057 	int	c;
3058 	Port_t	iobase;
3059 	struct siocnstate	sp;
3060 
3061 	if (minor(dev) == siogdbunit)
3062 		iobase = siogdbiobase;
3063 	else
3064 		iobase = siocniobase;
3065 	crit_enter();
3066 	siocnopen(&sp, iobase, comdefaultrate);
3067 	while (!(inb(iobase + com_lsr) & LSR_RXRDY))
3068 		;
3069 	c = inb(iobase + com_data);
3070 	siocnclose(&sp, iobase);
3071 	crit_exit();
3072 	return (c);
3073 }
3074 
3075 void
3076 siocnputc(dev, c)
3077 	cdev_t	dev;
3078 	int	c;
3079 {
3080 	struct siocnstate	sp;
3081 	Port_t	iobase;
3082 
3083 	if (minor(dev) == siogdbunit)
3084 		iobase = siogdbiobase;
3085 	else
3086 		iobase = siocniobase;
3087 	crit_enter();
3088 	siocnopen(&sp, iobase, comdefaultrate);
3089 	siocntxwait(iobase);
3090 	outb(iobase + com_data, c);
3091 	siocnclose(&sp, iobase);
3092 	crit_exit();
3093 }
3094 
3095 DRIVER_MODULE(sio, isa, sio_isa_driver, sio_devclass, 0, 0);
3096 #if NPCI > 0
3097 DRIVER_MODULE(sio, pci, sio_pci_driver, sio_devclass, 0, 0);
3098 #endif
3099 #if NPUC > 0
3100 DRIVER_MODULE(sio, puc, sio_puc_driver, sio_devclass, 0, 0);
3101 #endif
3102