xref: /dflybsd-src/sys/dev/serial/sio/sio.c (revision 52fe5e2acd3e12a809e00d83bd089fbfc2258dec)
1 /*-
2  * (MPSAFE)
3  *
4  * Copyright (c) 1991 The Regents of the University of California.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  * $FreeBSD: src/sys/isa/sio.c,v 1.291.2.35 2003/05/18 08:51:15 murray Exp $
36  * $DragonFly: src/sys/dev/serial/sio/sio.c,v 1.44 2008/07/23 16:39:33 dillon Exp $
37  *	from: @(#)com.c	7.5 (Berkeley) 5/16/91
38  *	from: i386/isa sio.c,v 1.234
39  */
40 
41 #include "opt_comconsole.h"
42 #include "opt_compat.h"
43 #include "opt_ddb.h"
44 #include "opt_sio.h"
45 #include "use_pci.h"
46 #ifdef __i386__
47 #include "use_puc.h"
48 #endif
49 #include "use_sio.h"
50 
51 /*
52  * Serial driver, based on 386BSD-0.1 com driver.
53  * Mostly rewritten to use pseudo-DMA.
54  * Works for National Semiconductor NS8250-NS16550AF UARTs.
55  * COM driver, based on HP dca driver.
56  *
57  * Changes for PC-Card integration:
58  *	- Added PC-Card driver table and handlers
59  */
60 #include <sys/param.h>
61 #include <sys/systm.h>
62 #include <sys/reboot.h>
63 #include <sys/malloc.h>
64 #include <sys/tty.h>
65 #include <sys/proc.h>
66 #include <sys/priv.h>
67 #include <sys/module.h>
68 #include <sys/conf.h>
69 #include <sys/dkstat.h>
70 #include <sys/fcntl.h>
71 #include <sys/interrupt.h>
72 #include <sys/kernel.h>
73 #include <sys/syslog.h>
74 #include <sys/sysctl.h>
75 #include <sys/bus.h>
76 #include <sys/rman.h>
77 #include <sys/timepps.h>
78 #include <sys/thread2.h>
79 #include <sys/devfs.h>
80 
81 #include <machine/limits.h>
82 
83 #include <bus/isa/isareg.h>
84 #include <bus/isa/isavar.h>
85 #if NPCI > 0
86 #include <bus/pci/pcireg.h>
87 #include <bus/pci/pcivar.h>
88 #endif
89 #if NPUC > 0
90 #include <dev/misc/puc/pucvar.h>
91 #endif
92 #include <machine/lock.h>
93 
94 #include <machine/clock.h>
95 #ifndef SMP
96 #include <machine/lock.h>
97 #endif
98 
99 #include "sioreg.h"
100 #include "sio_private.h"
101 
102 #ifdef COM_ESP
103 #include "../ic_layer/esp.h"
104 #endif
105 
106 #define	LOTS_OF_EVENTS	64	/* helps separate urgent events from input */
107 
108 #define	CALLOUT_MASK		0x80
109 #define	CONTROL_MASK		0x60
110 #define	CONTROL_INIT_STATE	0x20
111 #define	CONTROL_LOCK_STATE	0x40
112 #define	DEV_TO_UNIT(dev)	(MINOR_TO_UNIT(minor(dev)))
113 #define	MINOR_TO_UNIT(mynor)	((((mynor) & ~0xffffU) >> (8 + 3)) \
114 				 | ((mynor) & 0x1f))
115 #define	UNIT_TO_MINOR(unit)	((((unit) & ~0x1fU) << (8 + 3)) \
116 				 | ((unit) & 0x1f))
117 
118 #define	com_scr		7	/* scratch register for 16450-16550 (R/W) */
119 
120 #define	sio_getreg(com, off) \
121 	(bus_space_read_1((com)->bst, (com)->bsh, (off)))
122 #define	sio_setreg(com, off, value) \
123 	(bus_space_write_1((com)->bst, (com)->bsh, (off), (value)))
124 
125 /*
126  * com state bits.
127  * (CS_BUSY | CS_TTGO) and (CS_BUSY | CS_TTGO | CS_ODEVREADY) must be higher
128  * than the other bits so that they can be tested as a group without masking
129  * off the low bits.
130  *
131  * The following com and tty flags correspond closely:
132  *	CS_BUSY		= TS_BUSY (maintained by comstart(), siopoll() and
133  *				   comstop())
134  *	CS_TTGO		= ~TS_TTSTOP (maintained by comparam() and comstart())
135  *	CS_CTS_OFLOW	= CCTS_OFLOW (maintained by comparam())
136  *	CS_RTS_IFLOW	= CRTS_IFLOW (maintained by comparam())
137  * TS_FLUSH is not used.
138  * XXX I think TIOCSETA doesn't clear TS_TTSTOP when it clears IXON.
139  * XXX CS_*FLOW should be CF_*FLOW in com->flags (control flags not state).
140  */
141 #define	CS_BUSY		0x80	/* output in progress */
142 #define	CS_TTGO		0x40	/* output not stopped by XOFF */
143 #define	CS_ODEVREADY	0x20	/* external device h/w ready (CTS) */
144 #define	CS_CHECKMSR	1	/* check of MSR scheduled */
145 #define	CS_CTS_OFLOW	2	/* use CTS output flow control */
146 #define	CS_DTR_OFF	0x10	/* DTR held off */
147 #define	CS_ODONE	4	/* output completed */
148 #define	CS_RTS_IFLOW	8	/* use RTS input flow control */
149 #define	CSE_BUSYCHECK	1	/* siobusycheck() scheduled */
150 
151 static	char const * const	error_desc[] = {
152 #define	CE_OVERRUN			0
153 	"silo overflow",
154 #define	CE_INTERRUPT_BUF_OVERFLOW	1
155 	"interrupt-level buffer overflow",
156 #define	CE_TTY_BUF_OVERFLOW		2
157 	"tty-level buffer overflow",
158 };
159 
160 #ifdef COM_ESP
161 static	int	espattach	(struct com_s *com, Port_t esp_port);
162 #endif
163 static	int	sio_isa_attach	(device_t dev);
164 
165 static	timeout_t siobusycheck;
166 static	u_int	siodivisor	(u_long rclk, speed_t speed);
167 static	timeout_t siodtrwakeup;
168 static	void	comhardclose	(struct com_s *com);
169 static	void	sioinput	(struct com_s *com);
170 static	void	siointr1	(struct com_s *com);
171 static	void	siointr		(void *arg);
172 static	int	commctl		(struct com_s *com, int bits, int how);
173 static	int	comparam	(struct tty *tp, struct termios *t);
174 static	inthand2_t siopoll;
175 static	int	sio_isa_probe	(device_t dev);
176 static	void	siosettimeout	(void);
177 static	int	siosetwater	(struct com_s *com, speed_t speed);
178 static	void	comstart	(struct tty *tp);
179 static	void	comstop		(struct tty *tp, int rw);
180 static	timeout_t comwakeup;
181 static	void	disc_optim	(struct tty	*tp, struct termios *t,
182 				     struct com_s *com);
183 
184 #if NPCI > 0
185 static	int	sio_pci_attach (device_t dev);
186 static	void	sio_pci_kludge_unit (device_t dev);
187 static	int	sio_pci_probe (device_t dev);
188 #endif /* NPCI > 0 */
189 
190 #if NPUC > 0
191 static	int	sio_puc_attach (device_t dev);
192 static	int	sio_puc_probe (device_t dev);
193 #endif /* NPUC > 0 */
194 
195 static char driver_name[] = "sio";
196 
197 /* table and macro for fast conversion from a unit number to its com struct */
198 devclass_t	sio_devclass;
199 #define	com_addr(unit)	((struct com_s *) \
200 			 devclass_get_softc(sio_devclass, unit))
201 
202 static device_method_t sio_isa_methods[] = {
203 	/* Device interface */
204 	DEVMETHOD(device_probe,		sio_isa_probe),
205 	DEVMETHOD(device_attach,	sio_isa_attach),
206 
207 	{ 0, 0 }
208 };
209 
210 static driver_t sio_isa_driver = {
211 	driver_name,
212 	sio_isa_methods,
213 	sizeof(struct com_s),
214 };
215 
216 #if NPCI > 0
217 static device_method_t sio_pci_methods[] = {
218 	/* Device interface */
219 	DEVMETHOD(device_probe,		sio_pci_probe),
220 	DEVMETHOD(device_attach,	sio_pci_attach),
221 
222 	{ 0, 0 }
223 };
224 
225 static driver_t sio_pci_driver = {
226 	driver_name,
227 	sio_pci_methods,
228 	sizeof(struct com_s),
229 };
230 #endif /* NPCI > 0 */
231 
232 #if NPUC > 0
233 static device_method_t sio_puc_methods[] = {
234 	/* Device interface */
235 	DEVMETHOD(device_probe,		sio_puc_probe),
236 	DEVMETHOD(device_attach,	sio_puc_attach),
237 
238 	{ 0, 0 }
239 };
240 
241 static driver_t sio_puc_driver = {
242 	driver_name,
243 	sio_puc_methods,
244 	sizeof(struct com_s),
245 };
246 #endif /* NPUC > 0 */
247 
248 static	d_open_t	sioopen;
249 static	d_close_t	sioclose;
250 static	d_read_t	sioread;
251 static	d_write_t	siowrite;
252 static	d_ioctl_t	sioioctl;
253 
254 #define	CDEV_MAJOR	28
255 static struct dev_ops sio_ops = {
256 	{ driver_name, CDEV_MAJOR, D_TTY },
257 	.d_open =	sioopen,
258 	.d_close =	sioclose,
259 	.d_read =	sioread,
260 	.d_write =	siowrite,
261 	.d_ioctl =	sioioctl,
262 	.d_kqfilter =	ttykqfilter,
263 	.d_revoke =	ttyrevoke
264 };
265 
266 int	comconsole = -1;
267 static	volatile speed_t	comdefaultrate = CONSPEED;
268 static	u_long			comdefaultrclk = DEFAULT_RCLK;
269 SYSCTL_ULONG(_machdep, OID_AUTO, conrclk, CTLFLAG_RW, &comdefaultrclk, 0, "");
270 static	u_int	com_events;	/* input chars + weighted output completions */
271 static	Port_t	siocniobase;
272 static	int	siocnunit;
273 static	Port_t	siogdbiobase;
274 static	int	siogdbunit = -1;
275 static	bool_t	sio_registered;
276 static	int	sio_timeout;
277 static	int	sio_timeouts_until_log;
278 static	struct	callout	sio_timeout_handle;
279 static	int	sio_numunits;
280 
281 #ifdef COM_ESP
282 /* XXX configure this properly. */
283 static	Port_t	likely_com_ports[] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8, };
284 static	Port_t	likely_esp_ports[] = { 0x140, 0x180, 0x280, 0 };
285 #endif
286 
287 /*
288  * handle sysctl read/write requests for console speed
289  *
290  * In addition to setting comdefaultrate for I/O through /dev/console,
291  * also set the initial and lock values for the /dev/ttyXX device
292  * if there is one associated with the console.  Finally, if the /dev/tty
293  * device has already been open, change the speed on the open running port
294  * itself.
295  */
296 
297 static int
298 sysctl_machdep_comdefaultrate(SYSCTL_HANDLER_ARGS)
299 {
300 	int error;
301 	speed_t newspeed;
302 	struct com_s *com;
303 	struct tty *tp;
304 
305 	lwkt_gettoken(&tty_token);
306 	newspeed = comdefaultrate;
307 
308 	error = sysctl_handle_opaque(oidp, &newspeed, sizeof newspeed, req);
309 	if (error || !req->newptr) {
310 		lwkt_reltoken(&tty_token);
311 		return (error);
312 	}
313 
314 	comdefaultrate = newspeed;
315 
316 	if (comconsole < 0) {	/* serial console not selected? */
317 		lwkt_reltoken(&tty_token);
318 		return (0);
319 	}
320 
321 	com = com_addr(comconsole);
322 	if (com == NULL) {
323 		lwkt_reltoken(&tty_token);
324 		return (ENXIO);
325 	}
326 
327 	/*
328 	 * set the initial and lock rates for /dev/ttydXX and /dev/cuaXX
329 	 * (note, the lock rates really are boolean -- if non-zero, disallow
330 	 *  speed changes)
331 	 */
332 	com->it_in.c_ispeed  = com->it_in.c_ospeed =
333 	com->lt_in.c_ispeed  = com->lt_in.c_ospeed =
334 	com->it_out.c_ispeed = com->it_out.c_ospeed =
335 	com->lt_out.c_ispeed = com->lt_out.c_ospeed = comdefaultrate;
336 
337 	/*
338 	 * if we're open, change the running rate too
339 	 */
340 	tp = com->tp;
341 	if (tp && (tp->t_state & TS_ISOPEN)) {
342 		tp->t_termios.c_ispeed =
343 		tp->t_termios.c_ospeed = comdefaultrate;
344 		crit_enter();
345 		error = comparam(tp, &tp->t_termios);
346 		crit_exit();
347 	}
348 	lwkt_reltoken(&tty_token);
349 	return error;
350 }
351 
352 SYSCTL_PROC(_machdep, OID_AUTO, conspeed, CTLTYPE_INT | CTLFLAG_RW,
353 	    0, 0, sysctl_machdep_comdefaultrate, "I", "");
354 
355 #if NPCI > 0
356 struct pci_ids {
357 	u_int32_t	type;
358 	const char	*desc;
359 	int		rid;
360 };
361 
362 static struct pci_ids pci_ids[] = {
363 	{ 0x100812b9, "3COM PCI FaxModem", 0x10 },
364 	{ 0x2000131f, "CyberSerial (1-port) 16550", 0x10 },
365 	{ 0x01101407, "Koutech IOFLEX-2S PCI Dual Port Serial", 0x10 },
366 	{ 0x01111407, "Koutech IOFLEX-2S PCI Dual Port Serial", 0x10 },
367 	{ 0x048011c1, "Lucent kermit based PCI Modem", 0x14 },
368 	{ 0x95211415, "Oxford Semiconductor PCI Dual Port Serial", 0x10 },
369 	{ 0x7101135e, "SeaLevel Ultra 530.PCI Single Port Serial", 0x18 },
370 	{ 0x0000151f, "SmartLink 5634PCV SurfRider", 0x10 },
371 	{ 0x98459710, "Netmos Nm9845 PCI Bridge with Dual UART", 0x10 },
372 	{ 0x00000000, NULL, 0 }
373 };
374 
375 static int
376 sio_pci_attach(device_t dev)
377 {
378 	u_int32_t	type;
379 	struct pci_ids	*id;
380 
381 	type = pci_get_devid(dev);
382 	id = pci_ids;
383 	while (id->type && id->type != type)
384 		id++;
385 	if (id->desc == NULL)
386 		return (ENXIO);
387 	sio_pci_kludge_unit(dev);
388 	return (sioattach(dev, id->rid, 0UL));
389 }
390 
391 /*
392  * Don't cut and paste this to other drivers.  It is a horrible kludge
393  * which will fail to work and also be unnecessary in future versions.
394  */
395 static void
396 sio_pci_kludge_unit(device_t dev)
397 {
398 	devclass_t	dc;
399 	int		err;
400 	int		start;
401 	int		unit;
402 
403 	unit = 0;
404 	start = 0;
405 	while (resource_int_value("sio", unit, "port", &start) == 0 &&
406 	    start > 0)
407 		unit++;
408 	if (device_get_unit(dev) < unit) {
409 		dc = device_get_devclass(dev);
410 		while (devclass_get_device(dc, unit))
411 			unit++;
412 		device_printf(dev, "moving to sio%d\n", unit);
413 		err = device_set_unit(dev, unit);	/* EVIL DO NOT COPY */
414 		if (err)
415 			device_printf(dev, "error moving device %d\n", err);
416 	}
417 }
418 
419 static int
420 sio_pci_probe(device_t dev)
421 {
422 	u_int32_t	type;
423 	struct pci_ids	*id;
424 
425 	type = pci_get_devid(dev);
426 	id = pci_ids;
427 	while (id->type && id->type != type)
428 		id++;
429 	if (id->desc == NULL)
430 		return (ENXIO);
431 	device_set_desc(dev, id->desc);
432 	return (sioprobe(dev, id->rid, 0UL));
433 }
434 #endif /* NPCI > 0 */
435 
436 #if NPUC > 0
437 static int
438 sio_puc_attach(device_t dev)
439 {
440 	u_int rclk;
441 
442 	if (BUS_READ_IVAR(device_get_parent(dev), dev, PUC_IVAR_FREQ,
443 	    &rclk) != 0)
444 		rclk = DEFAULT_RCLK;
445 	return (sioattach(dev, 0, rclk));
446 }
447 
448 static int
449 sio_puc_probe(device_t dev)
450 {
451 	u_int rclk;
452 
453 	if (BUS_READ_IVAR(device_get_parent(dev), dev, PUC_IVAR_FREQ,
454 	    &rclk) != 0)
455 		rclk = DEFAULT_RCLK;
456 	return (sioprobe(dev, 0, rclk));
457 }
458 #endif /* NPUC */
459 
460 static struct isa_pnp_id sio_ids[] = {
461 	{0x0005d041, "Standard PC COM port"},	/* PNP0500 */
462 	{0x0105d041, "16550A-compatible COM port"},	/* PNP0501 */
463 	{0x0205d041, "Multiport serial device (non-intelligent 16550)"}, /* PNP0502 */
464 	{0x1005d041, "Generic IRDA-compatible device"},	/* PNP0510 */
465 	{0x1105d041, "Generic IRDA-compatible device"},	/* PNP0511 */
466 	/* Devices that do not have a compatid */
467 	{0x12206804, NULL},     /* ACH2012 - 5634BTS 56K Video Ready Modem */
468 	{0x7602a904, NULL},	/* AEI0276 - 56K v.90 Fax Modem (LKT) */
469 	{0x00007905, NULL},	/* AKY0000 - 56K Plug&Play Modem */
470 	{0x21107905, NULL},	/* AKY1021 - 56K Plug&Play Modem */
471 	{0x01405407, NULL},	/* AZT4001 - AZT3000 PnP SOUND DEVICE, MODEM */
472 	{0x56039008, NULL},	/* BDP0356 - Best Data 56x2 */
473 	{0x56159008, NULL},	/* BDP1556 - B.D. Smart One 56SPS,Voice Modem*/
474 	{0x36339008, NULL},	/* BDP3336 - Best Data Prods. 336F */
475 	{0x0014490a, NULL},	/* BRI1400 - Boca 33.6 PnP */
476 	{0x0015490a, NULL},	/* BRI1500 - Internal Fax Data */
477 	{0x0034490a, NULL},	/* BRI3400 - Internal ACF Modem */
478 	{0x0094490a, NULL},	/* BRI9400 - Boca K56Flex PnP */
479 	{0x00b4490a, NULL},	/* BRIB400 - Boca 56k PnP */
480 	{0x0030320d, NULL},	/* CIR3000 - Cirrus Logic V43 */
481 	{0x0100440e, NULL},	/* CRD0001 - Cardinal MVP288IV ? */
482 	{0x01308c0e, NULL},	/* CTL3001 - Creative Labs Phoneblaster */
483 	{0x36033610, NULL},     /* DAV0336 - DAVICOM 336PNP MODEM */
484 	{0x01009416, NULL},     /* ETT0001 - E-Tech Bullet 33k6 PnP */
485 	{0x0000aa1a, NULL},	/* FUJ0000 - FUJITSU Modem 33600 PNP/I2 */
486 	{0x1200c31e, NULL},	/* GVC0012 - VF1128HV-R9 (win modem?) */
487 	{0x0303c31e, NULL},	/* GVC0303 - MaxTech 33.6 PnP D/F/V */
488 	{0x0505c31e, NULL},	/* GVC0505 - GVC 56k Faxmodem */
489 	{0x0116c31e, NULL},	/* GVC1601 - Rockwell V.34 Plug & Play Modem */
490 	{0x0050c31e, NULL},	/* GVC5000 - some GVC modem */
491 	{0x3800f91e, NULL},	/* GWY0038 - Telepath with v.90 */
492 	{0x9062f91e, NULL},	/* GWY6290 - Telepath with x2 Technology */
493 	{0x8100e425, NULL},	/* IOD0081 - I-O DATA DEVICE,INC. IFML-560 */
494 	{0x21002534, NULL},	/* MAE0021 - Jetstream Int V.90 56k Voice Series 2*/
495 	{0x0000f435, NULL},	/* MOT0000 - Motorola ModemSURFR 33.6 Intern */
496 	{0x5015f435, NULL},	/* MOT1550 - Motorola ModemSURFR 56K Modem */
497 	{0xf015f435, NULL},	/* MOT15F0 - Motorola VoiceSURFR 56K Modem */
498 	{0x6045f435, NULL},	/* MOT4560 - Motorola ? */
499 	{0x61e7a338, NULL},	/* NECE761 - 33.6Modem */
500  	{0x08804f3f, NULL},	/* OZO8008 - Zoom  (33.6k Modem) */
501 	{0x0f804f3f, NULL},	/* OZO800f - Zoom 2812 (56k Modem) */
502 	{0x39804f3f, NULL},	/* OZO8039 - Zoom 56k flex */
503 	{0x00914f3f, NULL},	/* OZO9100 - Zoom 2919 (K56 Faxmodem) */
504 	{0x3024a341, NULL},	/* PMC2430 - Pace 56 Voice Internal Modem */
505 	{0x1000eb49, NULL},	/* ROK0010 - Rockwell ? */
506 	{0x1200b23d, NULL},     /* RSS0012 - OMRON ME5614ISA */
507 	{0x5002734a, NULL},	/* RSS0250 - 5614Jx3(G) Internal Modem */
508 	{0x6202734a, NULL},	/* RSS0262 - 5614Jx3[G] V90+K56Flex Modem */
509 	{0x1010104d, NULL},	/* SHP1010 - Rockwell 33600bps Modem */
510 	{0xc100ad4d, NULL},	/* SMM00C1 - Leopard 56k PnP */
511 	{0x9012b04e, NULL},	/* SUP1290 - Supra ? */
512 	{0x1013b04e, NULL},	/* SUP1310 - SupraExpress 336i PnP */
513 	{0x8013b04e, NULL},	/* SUP1380 - SupraExpress 288i PnP Voice */
514 	{0x8113b04e, NULL},	/* SUP1381 - SupraExpress 336i PnP Voice */
515 	{0x5016b04e, NULL},	/* SUP1650 - Supra 336i Sp Intl */
516 	{0x7016b04e, NULL},	/* SUP1670 - Supra 336i V+ Intl */
517 	{0x7420b04e, NULL},	/* SUP2070 - Supra ? */
518 	{0x8020b04e, NULL},	/* SUP2080 - Supra ? */
519 	{0x8420b04e, NULL},	/* SUP2084 - SupraExpress 56i PnP */
520 	{0x7121b04e, NULL},	/* SUP2171 - SupraExpress 56i Sp? */
521 	{0x8024b04e, NULL},	/* SUP2480 - Supra ? */
522 	{0x01007256, NULL},	/* USR0001 - U.S. Robotics Inc., Sportster W */
523 	{0x02007256, NULL},	/* USR0002 - U.S. Robotics Inc. Sportster 33. */
524 	{0x04007256, NULL},	/* USR0004 - USR Sportster 14.4k */
525 	{0x06007256, NULL},	/* USR0006 - USR Sportster 33.6k */
526 	{0x11007256, NULL},	/* USR0011 - USR ? */
527 	{0x01017256, NULL},	/* USR0101 - USR ? */
528 	{0x30207256, NULL},	/* USR2030 - U.S.Robotics Inc. Sportster 560 */
529 	{0x50207256, NULL},	/* USR2050 - U.S.Robotics Inc. Sportster 33. */
530 	{0x70207256, NULL},	/* USR2070 - U.S.Robotics Inc. Sportster 560 */
531 	{0x30307256, NULL},	/* USR3030 - U.S. Robotics 56K FAX INT */
532 	{0x31307256, NULL},	/* USR3031 - U.S. Robotics 56K FAX INT */
533 	{0x50307256, NULL},	/* USR3050 - U.S. Robotics 56K FAX INT */
534 	{0x70307256, NULL},	/* USR3070 - U.S. Robotics 56K Voice INT */
535 	{0x90307256, NULL},	/* USR3090 - USR ? */
536 	{0x70917256, NULL},	/* USR9170 - U.S. Robotics 56K FAX INT */
537 	{0x90917256, NULL},	/* USR9190 - USR 56k Voice INT */
538 	{0x0300695c, NULL},	/* WCI0003 - Fax/Voice/Modem/Speakphone/Asvd */
539 	{0x01a0896a, NULL},	/* ZTIA001 - Zoom Internal V90 Faxmodem */
540 	{0x61f7896a, NULL},	/* ZTIF761 - Zoom ComStar 33.6 */
541 	{0}
542 };
543 
544 
545 
546 static int
547 sio_isa_probe(device_t dev)
548 {
549 	/* Check isapnp ids */
550 	if (ISA_PNP_PROBE(device_get_parent(dev), dev, sio_ids) == ENXIO)
551 		return (ENXIO);
552 	return (sioprobe(dev, 0, 0UL));
553 }
554 
555 int
556 sioprobe(device_t dev, int xrid, u_long rclk)
557 {
558 #if 0
559 	static bool_t	already_init;
560 	device_t	xdev;
561 #endif
562 	struct com_s	*com;
563 	u_int		divisor;
564 	bool_t		failures[10];
565 	int		fn;
566 	device_t	idev;
567 	Port_t		iobase;
568 	intrmask_t	irqmap[4];
569 	intrmask_t	irqs;
570 	u_char		mcr_image;
571 	int		result;
572 	u_long		xirq;
573 	u_int		flags = device_get_flags(dev);
574 	int		rid;
575 	struct resource *port;
576 
577 	rid = xrid;
578 	port = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid,
579 				  0, ~0, IO_COMSIZE, RF_ACTIVE);
580 	if (!port)
581 		return (ENXIO);
582 
583 	lwkt_gettoken(&tty_token);
584 	com = device_get_softc(dev);
585 	com->bst = rman_get_bustag(port);
586 	com->bsh = rman_get_bushandle(port);
587 	if (rclk == 0)
588 		rclk = DEFAULT_RCLK;
589 	com->rclk = rclk;
590 
591 #if 0
592 	/*
593 	 * XXX this is broken - when we are first called, there are no
594 	 * previously configured IO ports.  We could hard code
595 	 * 0x3f8, 0x2f8, 0x3e8, 0x2e8 etc but that's probably worse.
596 	 * This code has been doing nothing since the conversion since
597 	 * "count" is zero the first time around.
598 	 */
599 	if (!already_init) {
600 		/*
601 		 * Turn off MCR_IENABLE for all likely serial ports.  An unused
602 		 * port with its MCR_IENABLE gate open will inhibit interrupts
603 		 * from any used port that shares the interrupt vector.
604 		 * XXX the gate enable is elsewhere for some multiports.
605 		 */
606 		device_t *devs;
607 		int count, i, xioport;
608 
609 		devclass_get_devices(sio_devclass, &devs, &count);
610 		for (i = 0; i < count; i++) {
611 			xdev = devs[i];
612 			if (device_is_enabled(xdev) &&
613 			    bus_get_resource(xdev, SYS_RES_IOPORT, 0, &xioport,
614 					     NULL) == 0)
615 				outb(xioport + com_mcr, 0);
616 		}
617 		kfree(devs, M_TEMP);
618 		already_init = TRUE;
619 	}
620 #endif
621 
622 	if (COM_LLCONSOLE(flags)) {
623 		kprintf("sio%d: reserved for low-level i/o\n",
624 		       device_get_unit(dev));
625 		bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
626 		lwkt_reltoken(&tty_token);
627 		return (ENXIO);
628 	}
629 
630 	/*
631 	 * If the device is on a multiport card and has an AST/4
632 	 * compatible interrupt control register, initialize this
633 	 * register and prepare to leave MCR_IENABLE clear in the mcr.
634 	 * Otherwise, prepare to set MCR_IENABLE in the mcr.
635 	 * Point idev to the device struct giving the correct id_irq.
636 	 * This is the struct for the master device if there is one.
637 	 */
638 	idev = dev;
639 	mcr_image = MCR_IENABLE;
640 #ifdef COM_MULTIPORT
641 	if (COM_ISMULTIPORT(flags)) {
642 		Port_t xiobase;
643 		u_long io;
644 
645 		idev = devclass_get_device(sio_devclass, COM_MPMASTER(flags));
646 		if (idev == NULL) {
647 			kprintf("sio%d: master device %d not configured\n",
648 			       device_get_unit(dev), COM_MPMASTER(flags));
649 			idev = dev;
650 		}
651 		if (!COM_NOTAST4(flags)) {
652 			if (bus_get_resource(idev, SYS_RES_IOPORT, 0, &io,
653 					     NULL) == 0) {
654 				xiobase = io;
655 				if (bus_get_resource(idev, SYS_RES_IRQ, 0,
656 				    NULL, NULL) == 0)
657 					outb(xiobase + com_scr, 0x80);
658 				else
659 					outb(xiobase + com_scr, 0);
660 			}
661 			mcr_image = 0;
662 		}
663 	}
664 #endif /* COM_MULTIPORT */
665 	if (bus_get_resource(idev, SYS_RES_IRQ, 0, NULL, NULL) != 0)
666 		mcr_image = 0;
667 
668 	bzero(failures, sizeof failures);
669 	iobase = rman_get_start(port);
670 
671 	/*
672 	 * We don't want to get actual interrupts, just masked ones.
673 	 * Interrupts from this line should already be masked in the ICU,
674 	 * but mask them in the processor as well in case there are some
675 	 * (misconfigured) shared interrupts.
676 	 */
677 	com_lock();
678 /* EXTRA DELAY? */
679 
680 	/*
681 	 * For the TI16754 chips, set prescaler to 1 (4 is often the
682 	 * default after-reset value) as otherwise it's impossible to
683 	 * get highest baudrates.
684 	 */
685 	if (COM_TI16754(flags)) {
686 		u_char cfcr, efr;
687 
688 		cfcr = sio_getreg(com, com_cfcr);
689 		sio_setreg(com, com_cfcr, CFCR_EFR_ENABLE);
690 		efr = sio_getreg(com, com_efr);
691 		/* Unlock extended features to turn off prescaler. */
692 		sio_setreg(com, com_efr, efr | EFR_EFE);
693 		/* Disable EFR. */
694 		sio_setreg(com, com_cfcr, (cfcr != CFCR_EFR_ENABLE) ? cfcr : 0);
695 		/* Turn off prescaler. */
696 		sio_setreg(com, com_mcr,
697 			   sio_getreg(com, com_mcr) & ~MCR_PRESCALE);
698 		sio_setreg(com, com_cfcr, CFCR_EFR_ENABLE);
699 		sio_setreg(com, com_efr, efr);
700 		sio_setreg(com, com_cfcr, cfcr);
701 	}
702 
703 	/*
704 	 * Initialize the speed and the word size and wait long enough to
705 	 * drain the maximum of 16 bytes of junk in device output queues.
706 	 * The speed is undefined after a master reset and must be set
707 	 * before relying on anything related to output.  There may be
708 	 * junk after a (very fast) soft reboot and (apparently) after
709 	 * master reset.
710 	 * XXX what about the UART bug avoided by waiting in comparam()?
711 	 * We don't want to to wait long enough to drain at 2 bps.
712 	 */
713 	if (iobase == siocniobase) {
714 		DELAY((16 + 1) * 1000000 / (comdefaultrate / 10));
715 	} else {
716 		sio_setreg(com, com_cfcr, CFCR_DLAB | CFCR_8BITS);
717 		divisor = siodivisor(rclk, SIO_TEST_SPEED);
718 		sio_setreg(com, com_dlbl, divisor & 0xff);
719 		sio_setreg(com, com_dlbh, divisor >> 8);
720 		sio_setreg(com, com_cfcr, CFCR_8BITS);
721 		DELAY((16 + 1) * 1000000 / (SIO_TEST_SPEED / 10));
722 	}
723 
724 	/*
725 	 * Make sure we can drain the receiver.  If we can't, the serial
726 	 * port may not exist.
727 	 */
728 	for (fn = 0; fn < 256; ++fn) {
729 		if ((sio_getreg(com, com_lsr) & LSR_RXRDY) == 0)
730 			break;
731 		(void)sio_getreg(com, com_data);
732 	}
733 	if (fn == 256) {
734 		kprintf("sio%d: can't drain, serial port might "
735 			"not exist, disabling\n", device_get_unit(dev));
736 		com_unlock();
737 		return (ENXIO);
738 	}
739 
740 	/*
741 	 * Enable the interrupt gate and disable device interupts.  This
742 	 * should leave the device driving the interrupt line low and
743 	 * guarantee an edge trigger if an interrupt can be generated.
744 	 */
745 /* EXTRA DELAY? */
746 	sio_setreg(com, com_mcr, mcr_image);
747 	sio_setreg(com, com_ier, 0);
748 	DELAY(1000);		/* XXX */
749 	irqmap[0] = isa_irq_pending();
750 
751 	/*
752 	 * Attempt to set loopback mode so that we can send a null byte
753 	 * without annoying any external device.
754 	 */
755 /* EXTRA DELAY? */
756 	sio_setreg(com, com_mcr, mcr_image | MCR_LOOPBACK);
757 
758 	/*
759 	 * Attempt to generate an output interrupt.  On 8250's, setting
760 	 * IER_ETXRDY generates an interrupt independent of the current
761 	 * setting and independent of whether the THR is empty.  On 16450's,
762 	 * setting IER_ETXRDY generates an interrupt independent of the
763 	 * current setting.  On 16550A's, setting IER_ETXRDY only
764 	 * generates an interrupt when IER_ETXRDY is not already set.
765 	 */
766 	sio_setreg(com, com_ier, IER_ETXRDY);
767 
768 	/*
769 	 * On some 16x50 incompatibles, setting IER_ETXRDY doesn't generate
770 	 * an interrupt.  They'd better generate one for actually doing
771 	 * output.  Loopback may be broken on the same incompatibles but
772 	 * it's unlikely to do more than allow the null byte out.
773 	 */
774 	sio_setreg(com, com_data, 0);
775 	DELAY((1 + 2) * 1000000 / (SIO_TEST_SPEED / 10));
776 
777 	/*
778 	 * Turn off loopback mode so that the interrupt gate works again
779 	 * (MCR_IENABLE was hidden).  This should leave the device driving
780 	 * an interrupt line high.  It doesn't matter if the interrupt
781 	 * line oscillates while we are not looking at it, since interrupts
782 	 * are disabled.
783 	 */
784 /* EXTRA DELAY? */
785 	sio_setreg(com, com_mcr, mcr_image);
786 
787 	/*
788 	 * Some pcmcia cards have the "TXRDY bug", so we check everyone
789 	 * for IIR_TXRDY implementation ( Palido 321s, DC-1S... )
790 	 */
791 	if (COM_NOPROBE(flags)) {
792 		/* Reading IIR register twice */
793 		for (fn = 0; fn < 2; fn ++) {
794 			DELAY(10000);
795 			failures[6] = sio_getreg(com, com_iir);
796 		}
797 		/* Check IIR_TXRDY clear ? */
798 		result = 0;
799 		if (failures[6] & IIR_TXRDY) {
800 			/* Nop, Double check with clearing IER */
801 			sio_setreg(com, com_ier, 0);
802 			if (sio_getreg(com, com_iir) & IIR_NOPEND) {
803 				/* Ok. we're familia this gang */
804 				SET_FLAG(dev, COM_C_IIR_TXRDYBUG);
805 			} else {
806 				/* Unknown, Just omit this chip.. XXX */
807 				result = ENXIO;
808 				sio_setreg(com, com_mcr, 0);
809 			}
810 		} else {
811 			/* OK. this is well-known guys */
812 			CLR_FLAG(dev, COM_C_IIR_TXRDYBUG);
813 		}
814 		sio_setreg(com, com_ier, 0);
815 		sio_setreg(com, com_cfcr, CFCR_8BITS);
816 		com_unlock();
817 		bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
818 		lwkt_reltoken(&tty_token);
819 		return (iobase == siocniobase ? 0 : result);
820 	}
821 
822 	/*
823 	 * Check that
824 	 *	o the CFCR, IER and MCR in UART hold the values written to them
825 	 *	  (the values happen to be all distinct - this is good for
826 	 *	  avoiding false positive tests from bus echoes).
827 	 *	o an output interrupt is generated and its vector is correct.
828 	 *	o the interrupt goes away when the IIR in the UART is read.
829 	 */
830 /* EXTRA DELAY? */
831 	failures[0] = sio_getreg(com, com_cfcr) - CFCR_8BITS;
832 	failures[1] = sio_getreg(com, com_ier) - IER_ETXRDY;
833 	failures[2] = sio_getreg(com, com_mcr) - mcr_image;
834 	DELAY(10000);		/* Some internal modems need this time */
835 	irqmap[1] = isa_irq_pending();
836 	failures[4] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_TXRDY;
837 	DELAY(1000);		/* XXX */
838 	irqmap[2] = isa_irq_pending();
839 	failures[6] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_NOPEND;
840 
841 	/*
842 	 * Turn off all device interrupts and check that they go off properly.
843 	 * Leave MCR_IENABLE alone.  For ports without a master port, it gates
844 	 * the OUT2 output of the UART to
845 	 * the ICU input.  Closing the gate would give a floating ICU input
846 	 * (unless there is another device driving it) and spurious interrupts.
847 	 * (On the system that this was first tested on, the input floats high
848 	 * and gives a (masked) interrupt as soon as the gate is closed.)
849 	 */
850 	sio_setreg(com, com_ier, 0);
851 	sio_setreg(com, com_cfcr, CFCR_8BITS);	/* dummy to avoid bus echo */
852 	failures[7] = sio_getreg(com, com_ier);
853 	DELAY(1000);		/* XXX */
854 	irqmap[3] = isa_irq_pending();
855 	failures[9] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_NOPEND;
856 
857 	com_unlock();
858 
859 	irqs = irqmap[1] & ~irqmap[0];
860 	if (bus_get_resource(idev, SYS_RES_IRQ, 0, &xirq, NULL) == 0 &&
861 	    ((1 << xirq) & irqs) == 0)
862 		kprintf(
863 		"sio%d: configured irq %ld not in bitmap of probed irqs %#x\n",
864 		    device_get_unit(dev), xirq, irqs);
865 	if (bootverbose)
866 		kprintf("sio%d: irq maps: %#x %#x %#x %#x\n",
867 		    device_get_unit(dev),
868 		    irqmap[0], irqmap[1], irqmap[2], irqmap[3]);
869 
870 	result = 0;
871 	for (fn = 0; fn < sizeof failures; ++fn)
872 		if (failures[fn]) {
873 			sio_setreg(com, com_mcr, 0);
874 			result = ENXIO;
875 			if (bootverbose) {
876 				kprintf("sio%d: probe failed test(s):",
877 				    device_get_unit(dev));
878 				for (fn = 0; fn < sizeof failures; ++fn)
879 					if (failures[fn])
880 						kprintf(" %d", fn);
881 				kprintf("\n");
882 			}
883 			break;
884 		}
885 	bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
886 	lwkt_reltoken(&tty_token);
887 	return (iobase == siocniobase ? 0 : result);
888 }
889 
890 #ifdef COM_ESP
891 static int
892 espattach(struct com_s *com, Port_t esp_port)
893 {
894 	u_char	dips;
895 	u_char	val;
896 
897 	/*
898 	 * Check the ESP-specific I/O port to see if we're an ESP
899 	 * card.  If not, return failure immediately.
900 	 */
901 	if ((inb(esp_port) & 0xf3) == 0) {
902 		kprintf(" port 0x%x is not an ESP board?\n", esp_port);
903 		return (0);
904 	}
905 
906 	lwkt_gettoken(&tty_token);
907 	/*
908 	 * We've got something that claims to be a Hayes ESP card.
909 	 * Let's hope so.
910 	 */
911 
912 	/* Get the dip-switch configuration */
913 	outb(esp_port + ESP_CMD1, ESP_GETDIPS);
914 	dips = inb(esp_port + ESP_STATUS1);
915 
916 	/*
917 	 * Bits 0,1 of dips say which COM port we are.
918 	 */
919 	if (rman_get_start(com->ioportres) == likely_com_ports[dips & 0x03])
920 		kprintf(" : ESP");
921 	else {
922 		kprintf(" esp_port has com %d\n", dips & 0x03);
923 		lwkt_reltoken(&tty_token);
924 		return (0);
925 	}
926 
927 	/*
928 	 * Check for ESP version 2.0 or later:  bits 4,5,6 = 010.
929 	 */
930 	outb(esp_port + ESP_CMD1, ESP_GETTEST);
931 	val = inb(esp_port + ESP_STATUS1);	/* clear reg 1 */
932 	val = inb(esp_port + ESP_STATUS2);
933 	if ((val & 0x70) < 0x20) {
934 		kprintf("-old (%o)", val & 0x70);
935 		lwkt_reltoken(&tty_token);
936 		return (0);
937 	}
938 
939 	/*
940 	 * Check for ability to emulate 16550:  bit 7 == 1
941 	 */
942 	if ((dips & 0x80) == 0) {
943 		kprintf(" slave");
944 		lwkt_reltoken(&tty_token);
945 		return (0);
946 	}
947 
948 	/*
949 	 * Okay, we seem to be a Hayes ESP card.  Whee.
950 	 */
951 	com->esp = TRUE;
952 	com->esp_port = esp_port;
953 	lwkt_reltoken(&tty_token);
954 	return (1);
955 }
956 #endif /* COM_ESP */
957 
958 static int
959 sio_isa_attach(device_t dev)
960 {
961 	return (sioattach(dev, 0, 0UL));
962 }
963 
964 int
965 sioattach(device_t dev, int xrid, u_long rclk)
966 {
967 	struct com_s	*com;
968 #ifdef COM_ESP
969 	Port_t		*espp;
970 #endif
971 	Port_t		iobase;
972 	int		minorbase;
973 	int		unit;
974 	u_int		flags;
975 	int		rid;
976 	struct resource *port;
977 	int		ret;
978 	static int	did_init;
979 
980 	lwkt_gettoken(&tty_token);
981 	if (did_init == 0) {
982 		did_init = 1;
983 		callout_init_mp(&sio_timeout_handle);
984 	}
985 
986 	rid = xrid;
987 	port = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid,
988 				  0, ~0, IO_COMSIZE, RF_ACTIVE);
989 	if (!port) {
990 		lwkt_reltoken(&tty_token);
991 		return (ENXIO);
992 	}
993 
994 	iobase = rman_get_start(port);
995 	unit = device_get_unit(dev);
996 	com = device_get_softc(dev);
997 	flags = device_get_flags(dev);
998 
999 	if (unit >= sio_numunits)
1000 		sio_numunits = unit + 1;
1001 	/*
1002 	 * sioprobe() has initialized the device registers as follows:
1003 	 *	o cfcr = CFCR_8BITS.
1004 	 *	  It is most important that CFCR_DLAB is off, so that the
1005 	 *	  data port is not hidden when we enable interrupts.
1006 	 *	o ier = 0.
1007 	 *	  Interrupts are only enabled when the line is open.
1008 	 *	o mcr = MCR_IENABLE, or 0 if the port has AST/4 compatible
1009 	 *	  interrupt control register or the config specifies no irq.
1010 	 *	  Keeping MCR_DTR and MCR_RTS off might stop the external
1011 	 *	  device from sending before we are ready.
1012 	 */
1013 	bzero(com, sizeof *com);
1014 	com->unit = unit;
1015 	com->ioportres = port;
1016 	com->bst = rman_get_bustag(port);
1017 	com->bsh = rman_get_bushandle(port);
1018 	com->cfcr_image = CFCR_8BITS;
1019 	com->dtr_wait = 3 * hz;
1020 	callout_init_mp(&com->dtr_ch);
1021 	callout_init_mp(&com->busy_ch);
1022 	com->loses_outints = COM_LOSESOUTINTS(flags) != 0;
1023 	com->no_irq = bus_get_resource(dev, SYS_RES_IRQ, 0, NULL, NULL) != 0;
1024 	com->tx_fifo_size = 1;
1025 	com->obufs[0].l_head = com->obuf1;
1026 	com->obufs[1].l_head = com->obuf2;
1027 
1028 	com->data_port = iobase + com_data;
1029 	com->int_id_port = iobase + com_iir;
1030 	com->modem_ctl_port = iobase + com_mcr;
1031 	com->mcr_image = inb(com->modem_ctl_port);
1032 	com->line_status_port = iobase + com_lsr;
1033 	com->modem_status_port = iobase + com_msr;
1034 	com->intr_ctl_port = iobase + com_ier;
1035 
1036 	if (rclk == 0)
1037 		rclk = DEFAULT_RCLK;
1038 	com->rclk = rclk;
1039 
1040 	/*
1041 	 * We don't use all the flags from <sys/ttydefaults.h> since they
1042 	 * are only relevant for logins.  It's important to have echo off
1043 	 * initially so that the line doesn't start blathering before the
1044 	 * echo flag can be turned off.
1045 	 */
1046 	com->it_in.c_iflag = 0;
1047 	com->it_in.c_oflag = 0;
1048 	com->it_in.c_cflag = TTYDEF_CFLAG;
1049 	com->it_in.c_lflag = 0;
1050 	if (unit == comconsole) {
1051 		com->it_in.c_iflag = TTYDEF_IFLAG;
1052 		com->it_in.c_oflag = TTYDEF_OFLAG;
1053 		com->it_in.c_cflag = TTYDEF_CFLAG | CLOCAL;
1054 		com->it_in.c_lflag = TTYDEF_LFLAG;
1055 		com->lt_out.c_cflag = com->lt_in.c_cflag = CLOCAL;
1056 		com->lt_out.c_ispeed = com->lt_out.c_ospeed =
1057 		com->lt_in.c_ispeed = com->lt_in.c_ospeed =
1058 		com->it_in.c_ispeed = com->it_in.c_ospeed = comdefaultrate;
1059 	} else
1060 		com->it_in.c_ispeed = com->it_in.c_ospeed = TTYDEF_SPEED;
1061 	if (siosetwater(com, com->it_in.c_ispeed) != 0) {
1062 		com_unlock();
1063 		/*
1064 		 * Leave i/o resources allocated if this is a `cn'-level
1065 		 * console, so that other devices can't snarf them.
1066 		 */
1067 		if (iobase != siocniobase)
1068 			bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
1069 		lwkt_reltoken(&tty_token);
1070 		return (ENOMEM);
1071 	}
1072 	com_unlock();
1073 	termioschars(&com->it_in);
1074 	com->it_out = com->it_in;
1075 
1076 	/* attempt to determine UART type */
1077 	kprintf("sio%d: type", unit);
1078 
1079 
1080 #ifdef COM_MULTIPORT
1081 	if (!COM_ISMULTIPORT(flags) && !COM_IIR_TXRDYBUG(flags))
1082 #else
1083 	if (!COM_IIR_TXRDYBUG(flags))
1084 #endif
1085 	{
1086 		u_char	scr;
1087 		u_char	scr1;
1088 		u_char	scr2;
1089 
1090 		scr = sio_getreg(com, com_scr);
1091 		sio_setreg(com, com_scr, 0xa5);
1092 		scr1 = sio_getreg(com, com_scr);
1093 		sio_setreg(com, com_scr, 0x5a);
1094 		scr2 = sio_getreg(com, com_scr);
1095 		sio_setreg(com, com_scr, scr);
1096 		if (scr1 != 0xa5 || scr2 != 0x5a) {
1097 			kprintf(" 8250");
1098 			goto determined_type;
1099 		}
1100 	}
1101 	sio_setreg(com, com_fifo, FIFO_ENABLE | FIFO_RX_HIGH);
1102 	DELAY(100);
1103 	com->st16650a = 0;
1104 	switch (inb(com->int_id_port) & IIR_FIFO_MASK) {
1105 	case FIFO_RX_LOW:
1106 		kprintf(" 16450");
1107 		break;
1108 	case FIFO_RX_MEDL:
1109 		kprintf(" 16450?");
1110 		break;
1111 	case FIFO_RX_MEDH:
1112 		kprintf(" 16550?");
1113 		break;
1114 	case FIFO_RX_HIGH:
1115 		if (COM_NOFIFO(flags)) {
1116 			kprintf(" 16550A fifo disabled");
1117 		} else {
1118 			com->hasfifo = TRUE;
1119 			if (COM_ST16650A(flags)) {
1120 				com->st16650a = 1;
1121 				com->tx_fifo_size = 32;
1122 				kprintf(" ST16650A");
1123 			} else if (COM_TI16754(flags)) {
1124 				com->tx_fifo_size = 64;
1125 				kprintf(" TI16754");
1126 			} else {
1127 				com->tx_fifo_size = COM_FIFOSIZE(flags);
1128 				kprintf(" 16550A");
1129 			}
1130 		}
1131 #ifdef COM_ESP
1132 		for (espp = likely_esp_ports; *espp != 0; espp++)
1133 			if (espattach(com, *espp)) {
1134 				com->tx_fifo_size = 1024;
1135 				break;
1136 			}
1137 #endif
1138 		if (!com->st16650a && !COM_TI16754(flags)) {
1139 			if (!com->tx_fifo_size)
1140 				com->tx_fifo_size = 16;
1141 			else
1142 				kprintf(" lookalike with %d bytes FIFO",
1143 				    com->tx_fifo_size);
1144 		}
1145 
1146 		break;
1147 	}
1148 
1149 #ifdef COM_ESP
1150 	if (com->esp) {
1151 		/*
1152 		 * Set 16550 compatibility mode.
1153 		 * We don't use the ESP_MODE_SCALE bit to increase the
1154 		 * fifo trigger levels because we can't handle large
1155 		 * bursts of input.
1156 		 * XXX flow control should be set in comparam(), not here.
1157 		 */
1158 		outb(com->esp_port + ESP_CMD1, ESP_SETMODE);
1159 		outb(com->esp_port + ESP_CMD2, ESP_MODE_RTS | ESP_MODE_FIFO);
1160 
1161 		/* Set RTS/CTS flow control. */
1162 		outb(com->esp_port + ESP_CMD1, ESP_SETFLOWTYPE);
1163 		outb(com->esp_port + ESP_CMD2, ESP_FLOW_RTS);
1164 		outb(com->esp_port + ESP_CMD2, ESP_FLOW_CTS);
1165 
1166 		/* Set flow-control levels. */
1167 		outb(com->esp_port + ESP_CMD1, ESP_SETRXFLOW);
1168 		outb(com->esp_port + ESP_CMD2, HIBYTE(768));
1169 		outb(com->esp_port + ESP_CMD2, LOBYTE(768));
1170 		outb(com->esp_port + ESP_CMD2, HIBYTE(512));
1171 		outb(com->esp_port + ESP_CMD2, LOBYTE(512));
1172 	}
1173 #endif /* COM_ESP */
1174 	sio_setreg(com, com_fifo, 0);
1175 determined_type: ;
1176 
1177 #ifdef COM_MULTIPORT
1178 	if (COM_ISMULTIPORT(flags)) {
1179 		device_t masterdev;
1180 
1181 		com->multiport = TRUE;
1182 		kprintf(" (multiport");
1183 		if (unit == COM_MPMASTER(flags))
1184 			kprintf(" master");
1185 		kprintf(")");
1186 		masterdev = devclass_get_device(sio_devclass,
1187 		    COM_MPMASTER(flags));
1188 		com->no_irq = (masterdev == NULL || bus_get_resource(masterdev,
1189 		    SYS_RES_IRQ, 0, NULL, NULL) != 0);
1190 	 }
1191 #endif /* COM_MULTIPORT */
1192 	if (unit == comconsole)
1193 		kprintf(", console");
1194 	if (COM_IIR_TXRDYBUG(flags))
1195 		kprintf(" with a bogus IIR_TXRDY register");
1196 	kprintf("\n");
1197 
1198 	if (!sio_registered) {
1199 		register_swi(SWI_TTY, siopoll, NULL ,"swi_siopoll", NULL);
1200 		sio_registered = TRUE;
1201 	}
1202 	minorbase = UNIT_TO_MINOR(unit);
1203 	make_dev(&sio_ops, minorbase,
1204 	    UID_ROOT, GID_WHEEL, 0600, "ttyd%r", unit);
1205 	make_dev(&sio_ops, minorbase | CONTROL_INIT_STATE,
1206 	    UID_ROOT, GID_WHEEL, 0600, "ttyid%r", unit);
1207 	make_dev(&sio_ops, minorbase | CONTROL_LOCK_STATE,
1208 	    UID_ROOT, GID_WHEEL, 0600, "ttyld%r", unit);
1209 	make_dev(&sio_ops, minorbase | CALLOUT_MASK,
1210 	    UID_UUCP, GID_DIALER, 0660, "cuaa%r", unit);
1211 	make_dev(&sio_ops, minorbase | CALLOUT_MASK | CONTROL_INIT_STATE,
1212 	    UID_UUCP, GID_DIALER, 0660, "cuaia%r", unit);
1213 	make_dev(&sio_ops, minorbase | CALLOUT_MASK | CONTROL_LOCK_STATE,
1214 	    UID_UUCP, GID_DIALER, 0660, "cuala%r", unit);
1215 	com->flags = flags;
1216 	com->pps.ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR;
1217 	pps_init(&com->pps);
1218 
1219 	rid = 0;
1220 	com->irqres = bus_alloc_resource(dev, SYS_RES_IRQ, &rid, 0ul, ~0ul, 1,
1221 	    RF_ACTIVE);
1222 	if (com->irqres) {
1223 		ret = BUS_SETUP_INTR(device_get_parent(dev), dev,
1224 				     com->irqres, INTR_MPSAFE, siointr, com,
1225 				     &com->cookie, NULL);
1226 		if (ret)
1227 			device_printf(dev, "could not activate interrupt\n");
1228 #if defined(DDB) && (defined(BREAK_TO_DEBUGGER) || \
1229     defined(ALT_BREAK_TO_DEBUGGER))
1230 		/*
1231 		 * Enable interrupts for early break-to-debugger support
1232 		 * on the console.
1233 		 */
1234 		if (ret == 0 && unit == comconsole)
1235 			outb(siocniobase + com_ier, IER_ERXRDY | IER_ERLS |
1236 			    IER_EMSC);
1237 #endif
1238 	}
1239 
1240 	lwkt_reltoken(&tty_token);
1241 	return (0);
1242 }
1243 
1244 static int
1245 sioopen(struct dev_open_args *ap)
1246 {
1247 	cdev_t dev = ap->a_head.a_dev;
1248 	struct com_s	*com;
1249 	int		error;
1250 	int		mynor;
1251 	struct tty	*tp;
1252 	int		unit;
1253 
1254 	mynor = minor(dev);
1255 	unit = MINOR_TO_UNIT(mynor);
1256 	com = com_addr(unit);
1257 	if (com == NULL)
1258 		return (ENXIO);
1259 	if (com->gone)
1260 		return (ENXIO);
1261 	if (mynor & CONTROL_MASK)
1262 		return (0);
1263 	lwkt_gettoken(&tty_token);
1264 	tp = dev->si_tty = com->tp = ttymalloc(com->tp);
1265 	crit_enter();
1266 	/*
1267 	 * We jump to this label after all non-interrupted sleeps to pick
1268 	 * up any changes of the device state.
1269 	 */
1270 open_top:
1271 	while (com->state & CS_DTR_OFF) {
1272 		error = tsleep(&com->dtr_wait, PCATCH, "siodtr", 0);
1273 		if (com_addr(unit) == NULL) {
1274 			crit_exit();
1275 			lwkt_reltoken(&tty_token);
1276 			return (ENXIO);
1277 		}
1278 		if (error != 0 || com->gone)
1279 			goto out;
1280 	}
1281 	if (tp->t_state & TS_ISOPEN) {
1282 		/*
1283 		 * The device is open, so everything has been initialized.
1284 		 * Handle conflicts.
1285 		 */
1286 		if (mynor & CALLOUT_MASK) {
1287 			if (!com->active_out) {
1288 				error = EBUSY;
1289 				goto out;
1290 			}
1291 		} else {
1292 			if (com->active_out) {
1293 				if (ap->a_oflags & O_NONBLOCK) {
1294 					error = EBUSY;
1295 					goto out;
1296 				}
1297 				error =	tsleep(&com->active_out,
1298 					       PCATCH, "siobi", 0);
1299 				if (com_addr(unit) == NULL) {
1300 					crit_exit();
1301 					lwkt_reltoken(&tty_token);
1302 					return (ENXIO);
1303 				}
1304 				if (error != 0 || com->gone)
1305 					goto out;
1306 				goto open_top;
1307 			}
1308 		}
1309 		if (tp->t_state & TS_XCLUDE && priv_check_cred(ap->a_cred, PRIV_ROOT, 0)) {
1310 			error = EBUSY;
1311 			goto out;
1312 		}
1313 	} else {
1314 		/*
1315 		 * The device isn't open, so there are no conflicts.
1316 		 * Initialize it.  Initialization is done twice in many
1317 		 * cases: to preempt sleeping callin opens if we are
1318 		 * callout, and to complete a callin open after DCD rises.
1319 		 */
1320 		tp->t_oproc = comstart;
1321 		tp->t_param = comparam;
1322 		tp->t_stop = comstop;
1323 		tp->t_dev = dev;
1324 		tp->t_termios = mynor & CALLOUT_MASK
1325 				? com->it_out : com->it_in;
1326 		(void)commctl(com, TIOCM_DTR | TIOCM_RTS, DMSET);
1327 		com->poll = com->no_irq;
1328 		com->poll_output = com->loses_outints;
1329 		++com->wopeners;
1330 		error = comparam(tp, &tp->t_termios);
1331 		--com->wopeners;
1332 		if (error != 0)
1333 			goto out;
1334 		/*
1335 		 * XXX we should goto open_top if comparam() slept.
1336 		 */
1337 		if (com->hasfifo) {
1338 			/*
1339 			 * (Re)enable and drain fifos.
1340 			 *
1341 			 * Certain SMC chips cause problems if the fifos
1342 			 * are enabled while input is ready.  Turn off the
1343 			 * fifo if necessary to clear the input.  We test
1344 			 * the input ready bit after enabling the fifos
1345 			 * since we've already enabled them in comparam()
1346 			 * and to handle races between enabling and fresh
1347 			 * input.
1348 			 */
1349 			while (TRUE) {
1350 				sio_setreg(com, com_fifo,
1351 					   FIFO_RCV_RST | FIFO_XMT_RST
1352 					   | com->fifo_image);
1353 				/*
1354 				 * XXX the delays are for superstitious
1355 				 * historical reasons.  It must be less than
1356 				 * the character time at the maximum
1357 				 * supported speed (87 usec at 115200 bps
1358 				 * 8N1).  Otherwise we might loop endlessly
1359 				 * if data is streaming in.  We used to use
1360 				 * delays of 100.  That usually worked
1361 				 * because DELAY(100) used to usually delay
1362 				 * for about 85 usec instead of 100.
1363 				 */
1364 				DELAY(50);
1365 				if (!(inb(com->line_status_port) & LSR_RXRDY))
1366 					break;
1367 				sio_setreg(com, com_fifo, 0);
1368 				DELAY(50);
1369 				(void) inb(com->data_port);
1370 			}
1371 		}
1372 
1373 		com_lock();
1374 		(void) inb(com->line_status_port);
1375 		(void) inb(com->data_port);
1376 		com->prev_modem_status = com->last_modem_status
1377 		    = inb(com->modem_status_port);
1378 		if (COM_IIR_TXRDYBUG(com->flags)) {
1379 			outb(com->intr_ctl_port, IER_ERXRDY | IER_ERLS
1380 						| IER_EMSC);
1381 		} else {
1382 			outb(com->intr_ctl_port, IER_ERXRDY | IER_ETXRDY
1383 						| IER_ERLS | IER_EMSC);
1384 		}
1385 		com_unlock();
1386 		/*
1387 		 * Handle initial DCD.  Callout devices get a fake initial
1388 		 * DCD (trapdoor DCD).  If we are callout, then any sleeping
1389 		 * callin opens get woken up and resume sleeping on "siobi"
1390 		 * instead of "siodcd".
1391 		 */
1392 		/*
1393 		 * XXX `mynor & CALLOUT_MASK' should be
1394 		 * `tp->t_cflag & (SOFT_CARRIER | TRAPDOOR_CARRIER) where
1395 		 * TRAPDOOR_CARRIER is the default initial state for callout
1396 		 * devices and SOFT_CARRIER is like CLOCAL except it hides
1397 		 * the true carrier.
1398 		 */
1399 		if (com->prev_modem_status & MSR_DCD || mynor & CALLOUT_MASK)
1400 			(*linesw[tp->t_line].l_modem)(tp, 1);
1401 	}
1402 	/*
1403 	 * Wait for DCD if necessary.
1404 	 */
1405 	if (!(tp->t_state & TS_CARR_ON) && !(mynor & CALLOUT_MASK)
1406 	    && !(tp->t_cflag & CLOCAL) && !(ap->a_oflags & O_NONBLOCK)) {
1407 		++com->wopeners;
1408 		error = tsleep(TSA_CARR_ON(tp), PCATCH, "siodcd", 0);
1409 		if (com_addr(unit) == NULL) {
1410 			crit_exit();
1411 			lwkt_reltoken(&tty_token);
1412 			return (ENXIO);
1413 		}
1414 		--com->wopeners;
1415 		if (error != 0 || com->gone)
1416 			goto out;
1417 		goto open_top;
1418 	}
1419 	error =	(*linesw[tp->t_line].l_open)(dev, tp);
1420 	disc_optim(tp, &tp->t_termios, com);
1421 	if (tp->t_state & TS_ISOPEN && mynor & CALLOUT_MASK)
1422 		com->active_out = TRUE;
1423 	siosettimeout();
1424 out:
1425 	crit_exit();
1426 	if (!(tp->t_state & TS_ISOPEN) && com->wopeners == 0)
1427 		comhardclose(com);
1428 	lwkt_reltoken(&tty_token);
1429 	return (error);
1430 }
1431 
1432 static int
1433 sioclose(struct dev_close_args *ap)
1434 {
1435 	cdev_t dev = ap->a_head.a_dev;
1436 	struct com_s	*com;
1437 	int		mynor;
1438 	struct tty	*tp;
1439 
1440 	mynor = minor(dev);
1441 	if (mynor & CONTROL_MASK)
1442 		return (0);
1443 	lwkt_gettoken(&tty_token);
1444 	com = com_addr(MINOR_TO_UNIT(mynor));
1445 	if (com == NULL) {
1446 		lwkt_reltoken(&tty_token);
1447 		return (ENODEV);
1448 	}
1449 	tp = com->tp;
1450 	crit_enter();
1451 	(*linesw[tp->t_line].l_close)(tp, ap->a_fflag);
1452 	disc_optim(tp, &tp->t_termios, com);
1453 	comstop(tp, FREAD | FWRITE);
1454 	comhardclose(com);
1455 	ttyclose(tp);
1456 	siosettimeout();
1457 	crit_exit();
1458 	if (com->gone) {
1459 		kprintf("sio%d: gone\n", com->unit);
1460 		crit_enter();
1461 		if (com->ibuf != NULL)
1462 			kfree(com->ibuf, M_DEVBUF);
1463 		bzero(tp, sizeof *tp);
1464 		crit_exit();
1465 	}
1466 	lwkt_reltoken(&tty_token);
1467 	return (0);
1468 }
1469 
1470 static void
1471 comhardclose(struct com_s *com)
1472 {
1473 	struct tty	*tp;
1474 	int		unit;
1475 
1476 	unit = com->unit;
1477 	crit_enter();
1478 	lwkt_gettoken(&tty_token);
1479 	com->poll = FALSE;
1480 	com->poll_output = FALSE;
1481 	com->do_timestamp = FALSE;
1482 	com->do_dcd_timestamp = FALSE;
1483 	com->pps.ppsparam.mode = 0;
1484 	sio_setreg(com, com_cfcr, com->cfcr_image &= ~CFCR_SBREAK);
1485 	tp = com->tp;
1486 
1487 #if defined(DDB) && (defined(BREAK_TO_DEBUGGER) || \
1488     defined(ALT_BREAK_TO_DEBUGGER))
1489 	/*
1490 	 * Leave interrupts enabled and don't clear DTR if this is the
1491 	 * console. This allows us to detect break-to-debugger events
1492 	 * while the console device is closed.
1493 	 */
1494 	if (com->unit != comconsole)
1495 #endif
1496 	{
1497 		sio_setreg(com, com_ier, 0);
1498 		if (tp->t_cflag & HUPCL
1499 		    /*
1500 		     * XXX we will miss any carrier drop between here and the
1501 		     * next open.  Perhaps we should watch DCD even when the
1502 		     * port is closed; it is not sufficient to check it at
1503 		     * the next open because it might go up and down while
1504 		     * we're not watching.
1505 		     */
1506 		    || (!com->active_out
1507 		        && !(com->prev_modem_status & MSR_DCD)
1508 		        && !(com->it_in.c_cflag & CLOCAL))
1509 		    || !(tp->t_state & TS_ISOPEN)) {
1510 			(void)commctl(com, TIOCM_DTR, DMBIC);
1511 			if (com->dtr_wait != 0 && !(com->state & CS_DTR_OFF)) {
1512 				callout_reset(&com->dtr_ch, com->dtr_wait,
1513 						siodtrwakeup, com);
1514 				com->state |= CS_DTR_OFF;
1515 			}
1516 		}
1517 	}
1518 	if (com->hasfifo) {
1519 		/*
1520 		 * Disable fifos so that they are off after controlled
1521 		 * reboots.  Some BIOSes fail to detect 16550s when the
1522 		 * fifos are enabled.
1523 		 */
1524 		sio_setreg(com, com_fifo, 0);
1525 	}
1526 	com->active_out = FALSE;
1527 	wakeup(&com->active_out);
1528 	wakeup(TSA_CARR_ON(tp));	/* restart any wopeners */
1529 	lwkt_reltoken(&tty_token);
1530 	crit_exit();
1531 }
1532 
1533 static int
1534 sioread(struct dev_read_args *ap)
1535 {
1536 	cdev_t dev = ap->a_head.a_dev;
1537 	int		mynor, ret;
1538 	struct com_s	*com;
1539 
1540 	lwkt_gettoken(&tty_token);
1541 	mynor = minor(dev);
1542 	if (mynor & CONTROL_MASK) {
1543 		lwkt_reltoken(&tty_token);
1544 		return (ENODEV);
1545 	}
1546 	com = com_addr(MINOR_TO_UNIT(mynor));
1547 	if (com == NULL || com->gone) {
1548 		lwkt_reltoken(&tty_token);
1549 		return (ENODEV);
1550 	}
1551 	ret = ((*linesw[com->tp->t_line].l_read)(com->tp, ap->a_uio, ap->a_ioflag));
1552 	lwkt_reltoken(&tty_token);
1553 	return ret;
1554 }
1555 
1556 static int
1557 siowrite(struct dev_write_args *ap)
1558 {
1559 	cdev_t dev = ap->a_head.a_dev;
1560 	int		mynor;
1561 	struct com_s	*com;
1562 	int		unit, ret;
1563 
1564 	lwkt_gettoken(&tty_token);
1565 	mynor = minor(dev);
1566 	if (mynor & CONTROL_MASK) {
1567 		lwkt_reltoken(&tty_token);
1568 		return (ENODEV);
1569 	}
1570 
1571 	unit = MINOR_TO_UNIT(mynor);
1572 	com = com_addr(unit);
1573 	if (com == NULL || com->gone) {
1574 		lwkt_reltoken(&tty_token);
1575 		return (ENODEV);
1576 	}
1577 	/*
1578 	 * (XXX) We disallow virtual consoles if the physical console is
1579 	 * a serial port.  This is in case there is a display attached that
1580 	 * is not the console.  In that situation we don't need/want the X
1581 	 * server taking over the console.
1582 	 */
1583 	if (constty != NULL && unit == comconsole)
1584 		constty = NULL;
1585 	ret = ((*linesw[com->tp->t_line].l_write)(com->tp, ap->a_uio, ap->a_ioflag));
1586 	lwkt_reltoken(&tty_token);
1587 	return ret;
1588 }
1589 
1590 static void
1591 siobusycheck(void *chan)
1592 {
1593 	struct com_s	*com;
1594 
1595 	lwkt_gettoken(&tty_token);
1596 	com = (struct com_s *)chan;
1597 
1598 	/*
1599 	 * Clear TS_BUSY if low-level output is complete.
1600 	 * spl locking is sufficient because siointr1() does not set CS_BUSY.
1601 	 * If siointr1() clears CS_BUSY after we look at it, then we'll get
1602 	 * called again.  Reading the line status port outside of siointr1()
1603 	 * is safe because CS_BUSY is clear so there are no output interrupts
1604 	 * to lose.
1605 	 */
1606 	crit_enter();
1607 	if (com->state & CS_BUSY)
1608 		com->extra_state &= ~CSE_BUSYCHECK;	/* False alarm. */
1609 	else if ((inb(com->line_status_port) & (LSR_TSRE | LSR_TXRDY))
1610 	    == (LSR_TSRE | LSR_TXRDY)) {
1611 		com->tp->t_state &= ~TS_BUSY;
1612 		ttwwakeup(com->tp);
1613 		com->extra_state &= ~CSE_BUSYCHECK;
1614 	} else {
1615 		callout_reset(&com->busy_ch, hz / 100, siobusycheck, com);
1616 	}
1617 	crit_exit();
1618 	lwkt_reltoken(&tty_token);
1619 }
1620 
1621 static u_int
1622 siodivisor(u_long rclk, speed_t speed)
1623 {
1624 	long	actual_speed;
1625 	u_int	divisor;
1626 	int	error;
1627 
1628 	if (speed == 0 || speed > ((speed_t)-1 - 1) / 8)
1629 		return (0);
1630 	divisor = (rclk / (8UL * speed) + 1) / 2;
1631 	if (divisor == 0 || divisor >= 65536)
1632 		return (0);
1633 	actual_speed = rclk / (16UL * divisor);
1634 
1635 	/* 10 times error in percent: */
1636 	error = ((actual_speed - (long)speed) * 2000 / (long)speed + 1) / 2;
1637 
1638 	/* 3.0% maximum error tolerance: */
1639 	if (error < -30 || error > 30)
1640 		return (0);
1641 
1642 	return (divisor);
1643 }
1644 
1645 static void
1646 siodtrwakeup(void *chan)
1647 {
1648 	struct com_s	*com;
1649 
1650 	lwkt_gettoken(&tty_token);
1651 	com = (struct com_s *)chan;
1652 	com->state &= ~CS_DTR_OFF;
1653 	wakeup(&com->dtr_wait);
1654 	lwkt_reltoken(&tty_token);
1655 }
1656 
1657 /*
1658  * NOTE: Must be called with tty_token held
1659  */
1660 static void
1661 sioinput(struct com_s *com)
1662 {
1663 	u_char		*buf;
1664 	int		incc;
1665 	u_char		line_status;
1666 	int		recv_data;
1667 	struct tty	*tp;
1668 
1669 	ASSERT_LWKT_TOKEN_HELD(&tty_token);
1670 	buf = com->ibuf;
1671 	tp = com->tp;
1672 	if (!(tp->t_state & TS_ISOPEN) || !(tp->t_cflag & CREAD)) {
1673 		com_events -= (com->iptr - com->ibuf);
1674 		com->iptr = com->ibuf;
1675 		return;
1676 	}
1677 	if (tp->t_state & TS_CAN_BYPASS_L_RINT) {
1678 		/*
1679 		 * Avoid the grotesquely inefficient lineswitch routine
1680 		 * (ttyinput) in "raw" mode.  It usually takes about 450
1681 		 * instructions (that's without canonical processing or echo!).
1682 		 * slinput is reasonably fast (usually 40 instructions plus
1683 		 * call overhead).
1684 		 */
1685 		do {
1686 			com_unlock();
1687 			incc = com->iptr - buf;
1688 			if (tp->t_rawq.c_cc + incc > tp->t_ihiwat
1689 			    && (com->state & CS_RTS_IFLOW
1690 				|| tp->t_iflag & IXOFF)
1691 			    && !(tp->t_state & TS_TBLOCK))
1692 				ttyblock(tp);
1693 			com->delta_error_counts[CE_TTY_BUF_OVERFLOW]
1694 				+= b_to_q((char *)buf, incc, &tp->t_rawq);
1695 			buf += incc;
1696 			tk_nin += incc;
1697 			tk_rawcc += incc;
1698 			tp->t_rawcc += incc;
1699 			ttwakeup(tp);
1700 			if (tp->t_state & TS_TTSTOP
1701 			    && (tp->t_iflag & IXANY
1702 				|| tp->t_cc[VSTART] == tp->t_cc[VSTOP])) {
1703 				tp->t_state &= ~TS_TTSTOP;
1704 				tp->t_lflag &= ~FLUSHO;
1705 				comstart(tp);
1706 			}
1707 			com_lock();
1708 		} while (buf < com->iptr);
1709 	} else {
1710 		do {
1711 			com_unlock();
1712 			line_status = buf[com->ierroff];
1713 			recv_data = *buf++;
1714 			if (line_status
1715 			    & (LSR_BI | LSR_FE | LSR_OE | LSR_PE)) {
1716 				if (line_status & LSR_BI)
1717 					recv_data |= TTY_BI;
1718 				if (line_status & LSR_FE)
1719 					recv_data |= TTY_FE;
1720 				if (line_status & LSR_OE)
1721 					recv_data |= TTY_OE;
1722 				if (line_status & LSR_PE)
1723 					recv_data |= TTY_PE;
1724 			}
1725 			(*linesw[tp->t_line].l_rint)(recv_data, tp);
1726 			com_lock();
1727 		} while (buf < com->iptr);
1728 	}
1729 	com_events -= (com->iptr - com->ibuf);
1730 	com->iptr = com->ibuf;
1731 
1732 	/*
1733 	 * There is now room for another low-level buffer full of input,
1734 	 * so enable RTS if it is now disabled and there is room in the
1735 	 * high-level buffer.
1736 	 */
1737 	if ((com->state & CS_RTS_IFLOW) && !(com->mcr_image & MCR_RTS) &&
1738 	    !(tp->t_state & TS_TBLOCK))
1739 		outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
1740 }
1741 
1742 void
1743 siointr(void *arg)
1744 {
1745 	lwkt_gettoken(&tty_token);
1746 #ifndef COM_MULTIPORT
1747 	com_lock();
1748 	siointr1((struct com_s *) arg);
1749 	com_unlock();
1750 #else /* COM_MULTIPORT */
1751 	bool_t		possibly_more_intrs;
1752 	int		unit;
1753 	struct com_s	*com;
1754 
1755 	/*
1756 	 * Loop until there is no activity on any port.  This is necessary
1757 	 * to get an interrupt edge more than to avoid another interrupt.
1758 	 * If the IRQ signal is just an OR of the IRQ signals from several
1759 	 * devices, then the edge from one may be lost because another is
1760 	 * on.
1761 	 */
1762 	com_lock();
1763 	do {
1764 		possibly_more_intrs = FALSE;
1765 		for (unit = 0; unit < sio_numunits; ++unit) {
1766 			com = com_addr(unit);
1767 			/*
1768 			 * XXX com_lock();
1769 			 * would it work here, or be counter-productive?
1770 			 */
1771 			if (com != NULL
1772 			    && !com->gone
1773 			    && (inb(com->int_id_port) & IIR_IMASK)
1774 			       != IIR_NOPEND) {
1775 				siointr1(com);
1776 				possibly_more_intrs = TRUE;
1777 			}
1778 			/* XXX com_unlock(); */
1779 		}
1780 	} while (possibly_more_intrs);
1781 	com_unlock();
1782 #endif /* COM_MULTIPORT */
1783 	lwkt_reltoken(&tty_token);
1784 }
1785 
1786 static void
1787 siointr1(struct com_s *com)
1788 {
1789 	u_char	line_status;
1790 	u_char	modem_status;
1791 	u_char	*ioptr;
1792 	u_char	recv_data;
1793 	u_char	int_ctl;
1794 	u_char	int_ctl_new;
1795 	u_int	count;
1796 
1797 	lwkt_gettoken(&tty_token);
1798 	int_ctl = inb(com->intr_ctl_port);
1799 	int_ctl_new = int_ctl;
1800 
1801 	while (!com->gone) {
1802 		if (com->pps.ppsparam.mode & PPS_CAPTUREBOTH) {
1803 			modem_status = inb(com->modem_status_port);
1804 		        if ((modem_status ^ com->last_modem_status) & MSR_DCD) {
1805 				count = sys_cputimer->count();
1806 				pps_event(&com->pps, count,
1807 				    (modem_status & MSR_DCD) ?
1808 				    PPS_CAPTUREASSERT : PPS_CAPTURECLEAR);
1809 			}
1810 		}
1811 		line_status = inb(com->line_status_port);
1812 
1813 		/* input event? (check first to help avoid overruns) */
1814 		while (line_status & LSR_RCV_MASK) {
1815 			/* break/unnattached error bits or real input? */
1816 			if (!(line_status & LSR_RXRDY))
1817 				recv_data = 0;
1818 			else
1819 				recv_data = inb(com->data_port);
1820 #if defined(DDB) && defined(ALT_BREAK_TO_DEBUGGER)
1821 			/*
1822 			 * Solaris implements a new BREAK which is initiated
1823 			 * by a character sequence CR ~ ^b which is similar
1824 			 * to a familiar pattern used on Sun servers by the
1825 			 * Remote Console.
1826 			 */
1827 #define	KEY_CRTLB	2	/* ^B */
1828 #define	KEY_CR		13	/* CR '\r' */
1829 #define	KEY_TILDE	126	/* ~ */
1830 
1831 			if (com->unit == comconsole) {
1832 				static int brk_state1 = 0, brk_state2 = 0;
1833 				if (recv_data == KEY_CR) {
1834 					brk_state1 = recv_data;
1835 					brk_state2 = 0;
1836 				} else if (brk_state1 == KEY_CR && (recv_data == KEY_TILDE || recv_data == KEY_CRTLB)) {
1837 					if (recv_data == KEY_TILDE)
1838 						brk_state2 = recv_data;
1839 					else if (brk_state2 == KEY_TILDE && recv_data == KEY_CRTLB) {
1840 							breakpoint();
1841 							brk_state1 = brk_state2 = 0;
1842 							goto cont;
1843 					} else
1844 						brk_state2 = 0;
1845 				} else
1846 					brk_state1 = 0;
1847 			}
1848 #endif
1849 			if (line_status & (LSR_BI | LSR_FE | LSR_PE)) {
1850 				/*
1851 				 * Don't store BI if IGNBRK or FE/PE if IGNPAR.
1852 				 * Otherwise, push the work to a higher level
1853 				 * (to handle PARMRK) if we're bypassing.
1854 				 * Otherwise, convert BI/FE and PE+INPCK to 0.
1855 				 *
1856 				 * This makes bypassing work right in the
1857 				 * usual "raw" case (IGNBRK set, and IGNPAR
1858 				 * and INPCK clear).
1859 				 *
1860 				 * Note: BI together with FE/PE means just BI.
1861 				 */
1862 				if (line_status & LSR_BI) {
1863 #if defined(DDB) && defined(BREAK_TO_DEBUGGER)
1864 					if (com->unit == comconsole) {
1865 						breakpoint();
1866 						goto cont;
1867 					}
1868 #endif
1869 					if (com->tp == NULL
1870 					    || com->tp->t_iflag & IGNBRK)
1871 						goto cont;
1872 				} else {
1873 					if (com->tp == NULL
1874 					    || com->tp->t_iflag & IGNPAR)
1875 						goto cont;
1876 				}
1877 				if (com->tp->t_state & TS_CAN_BYPASS_L_RINT
1878 				    && (line_status & (LSR_BI | LSR_FE)
1879 					|| com->tp->t_iflag & INPCK))
1880 					recv_data = 0;
1881 			}
1882 			++com->bytes_in;
1883 			if (com->hotchar != 0 && recv_data == com->hotchar)
1884 				setsofttty();
1885 			ioptr = com->iptr;
1886 			if (ioptr >= com->ibufend)
1887 				CE_RECORD(com, CE_INTERRUPT_BUF_OVERFLOW);
1888 			else {
1889 				if (com->do_timestamp)
1890 					microtime(&com->timestamp);
1891 				++com_events;
1892 				schedsofttty();
1893 #if 0 /* for testing input latency vs efficiency */
1894 if (com->iptr - com->ibuf == 8)
1895 	setsofttty();
1896 #endif
1897 				ioptr[0] = recv_data;
1898 				ioptr[com->ierroff] = line_status;
1899 				com->iptr = ++ioptr;
1900 				if (ioptr == com->ihighwater
1901 				    && com->state & CS_RTS_IFLOW)
1902 					outb(com->modem_ctl_port,
1903 					     com->mcr_image &= ~MCR_RTS);
1904 				if (line_status & LSR_OE)
1905 					CE_RECORD(com, CE_OVERRUN);
1906 			}
1907 cont:
1908 			/*
1909 			 * "& 0x7F" is to avoid the gcc-1.40 generating a slow
1910 			 * jump from the top of the loop to here
1911 			 */
1912 			line_status = inb(com->line_status_port) & 0x7F;
1913 		}
1914 
1915 		/* modem status change? (always check before doing output) */
1916 		modem_status = inb(com->modem_status_port);
1917 		if (modem_status != com->last_modem_status) {
1918 			if (com->do_dcd_timestamp
1919 			    && !(com->last_modem_status & MSR_DCD)
1920 			    && modem_status & MSR_DCD)
1921 				microtime(&com->dcd_timestamp);
1922 
1923 			/*
1924 			 * Schedule high level to handle DCD changes.  Note
1925 			 * that we don't use the delta bits anywhere.  Some
1926 			 * UARTs mess them up, and it's easy to remember the
1927 			 * previous bits and calculate the delta.
1928 			 */
1929 			com->last_modem_status = modem_status;
1930 			if (!(com->state & CS_CHECKMSR)) {
1931 				com_events += LOTS_OF_EVENTS;
1932 				com->state |= CS_CHECKMSR;
1933 				setsofttty();
1934 			}
1935 
1936 			/* handle CTS change immediately for crisp flow ctl */
1937 			if (com->state & CS_CTS_OFLOW) {
1938 				if (modem_status & MSR_CTS)
1939 					com->state |= CS_ODEVREADY;
1940 				else
1941 					com->state &= ~CS_ODEVREADY;
1942 			}
1943 		}
1944 
1945 		/* output queued and everything ready? */
1946 		if (line_status & LSR_TXRDY
1947 		    && com->state >= (CS_BUSY | CS_TTGO | CS_ODEVREADY)) {
1948 			ioptr = com->obufq.l_head;
1949 			if (com->tx_fifo_size > 1) {
1950 				u_int	ocount;
1951 
1952 				ocount = com->obufq.l_tail - ioptr;
1953 				if (ocount > com->tx_fifo_size)
1954 					ocount = com->tx_fifo_size;
1955 				com->bytes_out += ocount;
1956 				do
1957 					outb(com->data_port, *ioptr++);
1958 				while (--ocount != 0);
1959 			} else {
1960 				outb(com->data_port, *ioptr++);
1961 				++com->bytes_out;
1962 			}
1963 			com->obufq.l_head = ioptr;
1964 			if (COM_IIR_TXRDYBUG(com->flags)) {
1965 				int_ctl_new = int_ctl | IER_ETXRDY;
1966 			}
1967 			if (ioptr >= com->obufq.l_tail) {
1968 				struct lbq	*qp;
1969 
1970 				qp = com->obufq.l_next;
1971 				qp->l_queued = FALSE;
1972 				qp = qp->l_next;
1973 				if (qp != NULL) {
1974 					com->obufq.l_head = qp->l_head;
1975 					com->obufq.l_tail = qp->l_tail;
1976 					com->obufq.l_next = qp;
1977 				} else {
1978 					/* output just completed */
1979 					if (COM_IIR_TXRDYBUG(com->flags)) {
1980 						int_ctl_new = int_ctl & ~IER_ETXRDY;
1981 					}
1982 					com->state &= ~CS_BUSY;
1983 				}
1984 				if (!(com->state & CS_ODONE)) {
1985 					com_events += LOTS_OF_EVENTS;
1986 					com->state |= CS_ODONE;
1987 					setsofttty();	/* handle at high level ASAP */
1988 				}
1989 			}
1990 			if (COM_IIR_TXRDYBUG(com->flags) && (int_ctl != int_ctl_new)) {
1991 				outb(com->intr_ctl_port, int_ctl_new);
1992 			}
1993 		}
1994 
1995 		/* finished? */
1996 #ifndef COM_MULTIPORT
1997 		if ((inb(com->int_id_port) & IIR_IMASK) == IIR_NOPEND)
1998 #endif /* COM_MULTIPORT */
1999 		{
2000 			lwkt_reltoken(&tty_token);
2001 			return;
2002 		}
2003 	}
2004 	lwkt_reltoken(&tty_token);
2005 }
2006 
2007 static int
2008 sioioctl(struct dev_ioctl_args *ap)
2009 {
2010 	cdev_t dev = ap->a_head.a_dev;
2011 	caddr_t data = ap->a_data;
2012 	struct com_s	*com;
2013 	int		error;
2014 	int		mynor;
2015 	struct tty	*tp;
2016 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
2017 	u_long		oldcmd;
2018 	struct termios	term;
2019 #endif
2020 	lwkt_gettoken(&tty_token);
2021 	mynor = minor(dev);
2022 
2023 	com = com_addr(MINOR_TO_UNIT(mynor));
2024 	if (com == NULL || com->gone) {
2025 		lwkt_reltoken(&tty_token);
2026 		return (ENODEV);
2027 	}
2028 	if (mynor & CONTROL_MASK) {
2029 		struct termios	*ct;
2030 
2031 		switch (mynor & CONTROL_MASK) {
2032 		case CONTROL_INIT_STATE:
2033 			ct = mynor & CALLOUT_MASK ? &com->it_out : &com->it_in;
2034 			break;
2035 		case CONTROL_LOCK_STATE:
2036 			ct = mynor & CALLOUT_MASK ? &com->lt_out : &com->lt_in;
2037 			break;
2038 		default:
2039 			lwkt_reltoken(&tty_token);
2040 			return (ENODEV);	/* /dev/nodev */
2041 		}
2042 		switch (ap->a_cmd) {
2043 		case TIOCSETA:
2044 			error = priv_check_cred(ap->a_cred, PRIV_ROOT, 0);
2045 			if (error != 0)
2046 				return (error);
2047 			*ct = *(struct termios *)data;
2048 			lwkt_reltoken(&tty_token);
2049 			return (0);
2050 		case TIOCGETA:
2051 			*(struct termios *)data = *ct;
2052 			lwkt_reltoken(&tty_token);
2053 			return (0);
2054 		case TIOCGETD:
2055 			*(int *)data = TTYDISC;
2056 			lwkt_reltoken(&tty_token);
2057 			return (0);
2058 		case TIOCGWINSZ:
2059 			bzero(data, sizeof(struct winsize));
2060 			lwkt_reltoken(&tty_token);
2061 			return (0);
2062 		default:
2063 			lwkt_reltoken(&tty_token);
2064 			return (ENOTTY);
2065 		}
2066 	}
2067 	tp = com->tp;
2068 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
2069 	term = tp->t_termios;
2070 	oldcmd = ap->a_cmd;
2071 	error = ttsetcompat(tp, &ap->a_cmd, data, &term);
2072 	if (error != 0) {
2073 		lwkt_reltoken(&tty_token);
2074 		return (error);
2075 	}
2076 	if (ap->a_cmd != oldcmd)
2077 		data = (caddr_t)&term;
2078 #endif
2079 	if (ap->a_cmd == TIOCSETA || ap->a_cmd == TIOCSETAW ||
2080 	    ap->a_cmd == TIOCSETAF) {
2081 		int	cc;
2082 		struct termios *dt = (struct termios *)data;
2083 		struct termios *lt = mynor & CALLOUT_MASK
2084 				     ? &com->lt_out : &com->lt_in;
2085 
2086 		dt->c_iflag = (tp->t_iflag & lt->c_iflag)
2087 			      | (dt->c_iflag & ~lt->c_iflag);
2088 		dt->c_oflag = (tp->t_oflag & lt->c_oflag)
2089 			      | (dt->c_oflag & ~lt->c_oflag);
2090 		dt->c_cflag = (tp->t_cflag & lt->c_cflag)
2091 			      | (dt->c_cflag & ~lt->c_cflag);
2092 		dt->c_lflag = (tp->t_lflag & lt->c_lflag)
2093 			      | (dt->c_lflag & ~lt->c_lflag);
2094 		for (cc = 0; cc < NCCS; ++cc)
2095 			if (lt->c_cc[cc] != 0)
2096 				dt->c_cc[cc] = tp->t_cc[cc];
2097 		if (lt->c_ispeed != 0)
2098 			dt->c_ispeed = tp->t_ispeed;
2099 		if (lt->c_ospeed != 0)
2100 			dt->c_ospeed = tp->t_ospeed;
2101 	}
2102 	error = (*linesw[tp->t_line].l_ioctl)(tp, ap->a_cmd, data, ap->a_fflag, ap->a_cred);
2103 	if (error != ENOIOCTL) {
2104 		lwkt_reltoken(&tty_token);
2105 		return (error);
2106 	}
2107 	crit_enter();
2108 	error = ttioctl(tp, ap->a_cmd, data, ap->a_fflag);
2109 	disc_optim(tp, &tp->t_termios, com);
2110 	if (error != ENOIOCTL) {
2111 		crit_exit();
2112 		lwkt_reltoken(&tty_token);
2113 		return (error);
2114 	}
2115 	switch (ap->a_cmd) {
2116 	case TIOCSBRK:
2117 		sio_setreg(com, com_cfcr, com->cfcr_image |= CFCR_SBREAK);
2118 		break;
2119 	case TIOCCBRK:
2120 		sio_setreg(com, com_cfcr, com->cfcr_image &= ~CFCR_SBREAK);
2121 		break;
2122 	case TIOCSDTR:
2123 		(void)commctl(com, TIOCM_DTR, DMBIS);
2124 		break;
2125 	case TIOCCDTR:
2126 		(void)commctl(com, TIOCM_DTR, DMBIC);
2127 		break;
2128 	/*
2129 	 * XXX should disallow changing MCR_RTS if CS_RTS_IFLOW is set.  The
2130 	 * changes get undone on the next call to comparam().
2131 	 */
2132 	case TIOCMSET:
2133 		(void)commctl(com, *(int *)data, DMSET);
2134 		break;
2135 	case TIOCMBIS:
2136 		(void)commctl(com, *(int *)data, DMBIS);
2137 		break;
2138 	case TIOCMBIC:
2139 		(void)commctl(com, *(int *)data, DMBIC);
2140 		break;
2141 	case TIOCMGET:
2142 		*(int *)data = commctl(com, 0, DMGET);
2143 		break;
2144 	case TIOCMSDTRWAIT:
2145 		/* must be root since the wait applies to following logins */
2146 		error = priv_check_cred(ap->a_cred, PRIV_ROOT, 0);
2147 		if (error != 0) {
2148 			crit_exit();
2149 			lwkt_reltoken(&tty_token);
2150 			return (error);
2151 		}
2152 		com->dtr_wait = *(int *)data * hz / 100;
2153 		break;
2154 	case TIOCMGDTRWAIT:
2155 		*(int *)data = com->dtr_wait * 100 / hz;
2156 		break;
2157 	case TIOCTIMESTAMP:
2158 		com->do_timestamp = TRUE;
2159 		*(struct timeval *)data = com->timestamp;
2160 		break;
2161 	case TIOCDCDTIMESTAMP:
2162 		com->do_dcd_timestamp = TRUE;
2163 		*(struct timeval *)data = com->dcd_timestamp;
2164 		break;
2165 	default:
2166 		crit_exit();
2167 		error = pps_ioctl(ap->a_cmd, data, &com->pps);
2168 		if (error == ENODEV)
2169 			error = ENOTTY;
2170 		lwkt_reltoken(&tty_token);
2171 		return (error);
2172 	}
2173 	crit_exit();
2174 	lwkt_reltoken(&tty_token);
2175 	return (0);
2176 }
2177 
2178 static void
2179 siopoll(void *dummy, void *frame)
2180 {
2181 	int		unit;
2182 
2183 	lwkt_gettoken(&tty_token);
2184 	if (com_events == 0) {
2185 		lwkt_reltoken(&tty_token);
2186 		return;
2187 	}
2188 
2189 repeat:
2190 	for (unit = 0; unit < sio_numunits; ++unit) {
2191 		struct com_s	*com;
2192 		int		incc;
2193 		struct tty	*tp;
2194 
2195 		com = com_addr(unit);
2196 		if (com == NULL)
2197 			continue;
2198 		tp = com->tp;
2199 		if (tp == NULL || com->gone) {
2200 			/*
2201 			 * Discard any events related to never-opened or
2202 			 * going-away devices.
2203 			 */
2204 			com_lock();
2205 			incc = com->iptr - com->ibuf;
2206 			com->iptr = com->ibuf;
2207 			if (com->state & CS_CHECKMSR) {
2208 				incc += LOTS_OF_EVENTS;
2209 				com->state &= ~CS_CHECKMSR;
2210 			}
2211 			com_events -= incc;
2212 			com_unlock();
2213 			continue;
2214 		}
2215 		if (com->iptr != com->ibuf) {
2216 			com_lock();
2217 			sioinput(com);
2218 			com_unlock();
2219 		}
2220 		if (com->state & CS_CHECKMSR) {
2221 			u_char	delta_modem_status;
2222 
2223 			com_lock();
2224 			delta_modem_status = com->last_modem_status
2225 					     ^ com->prev_modem_status;
2226 			com->prev_modem_status = com->last_modem_status;
2227 			com_events -= LOTS_OF_EVENTS;
2228 			com->state &= ~CS_CHECKMSR;
2229 			com_unlock();
2230 			if (delta_modem_status & MSR_DCD)
2231 				(*linesw[tp->t_line].l_modem)
2232 					(tp, com->prev_modem_status & MSR_DCD);
2233 		}
2234 		if (com->state & CS_ODONE) {
2235 			com_lock();
2236 			com_events -= LOTS_OF_EVENTS;
2237 			com->state &= ~CS_ODONE;
2238 			com_unlock();
2239 			if (!(com->state & CS_BUSY)
2240 			    && !(com->extra_state & CSE_BUSYCHECK)) {
2241 				callout_reset(&com->busy_ch, hz / 100,
2242 						siobusycheck, com);
2243 				com->extra_state |= CSE_BUSYCHECK;
2244 			}
2245 			(*linesw[tp->t_line].l_start)(tp);
2246 		}
2247 		if (com_events == 0)
2248 			break;
2249 	}
2250 	if (com_events >= LOTS_OF_EVENTS)
2251 		goto repeat;
2252 	lwkt_reltoken(&tty_token);
2253 }
2254 
2255 static int
2256 comparam(struct tty *tp, struct termios *t)
2257 {
2258 	u_int		cfcr;
2259 	int		cflag;
2260 	struct com_s	*com;
2261 	u_int		divisor;
2262 	u_char		dlbh;
2263 	u_char		dlbl;
2264 	int		unit;
2265 
2266 	lwkt_gettoken(&tty_token);
2267 	unit = DEV_TO_UNIT(tp->t_dev);
2268 	com = com_addr(unit);
2269 	if (com == NULL) {
2270 		lwkt_reltoken(&tty_token);
2271 		return (ENODEV);
2272 	}
2273 
2274 	/* do historical conversions */
2275 	if (t->c_ispeed == 0)
2276 		t->c_ispeed = t->c_ospeed;
2277 
2278 	/* check requested parameters */
2279 	if (t->c_ospeed == 0)
2280 		divisor = 0;
2281 	else {
2282 		if (t->c_ispeed != t->c_ospeed) {
2283 			lwkt_reltoken(&tty_token);
2284 			return (EINVAL);
2285 		}
2286 		divisor = siodivisor(com->rclk, t->c_ispeed);
2287 		if (divisor == 0) {
2288 			lwkt_reltoken(&tty_token);
2289 			return (EINVAL);
2290 		}
2291 	}
2292 
2293 	/* parameters are OK, convert them to the com struct and the device */
2294 	crit_enter();
2295 	if (divisor == 0)
2296 		(void)commctl(com, TIOCM_DTR, DMBIC);	/* hang up line */
2297 	else
2298 		(void)commctl(com, TIOCM_DTR, DMBIS);
2299 	cflag = t->c_cflag;
2300 	switch (cflag & CSIZE) {
2301 	case CS5:
2302 		cfcr = CFCR_5BITS;
2303 		break;
2304 	case CS6:
2305 		cfcr = CFCR_6BITS;
2306 		break;
2307 	case CS7:
2308 		cfcr = CFCR_7BITS;
2309 		break;
2310 	default:
2311 		cfcr = CFCR_8BITS;
2312 		break;
2313 	}
2314 	if (cflag & PARENB) {
2315 		cfcr |= CFCR_PENAB;
2316 		if (!(cflag & PARODD))
2317 			cfcr |= CFCR_PEVEN;
2318 	}
2319 	if (cflag & CSTOPB)
2320 		cfcr |= CFCR_STOPB;
2321 
2322 	if (com->hasfifo && divisor != 0) {
2323 		/*
2324 		 * Use a fifo trigger level low enough so that the input
2325 		 * latency from the fifo is less than about 16 msec and
2326 		 * the total latency is less than about 30 msec.  These
2327 		 * latencies are reasonable for humans.  Serial comms
2328 		 * protocols shouldn't expect anything better since modem
2329 		 * latencies are larger.
2330 		 *
2331 		 * Interrupts can be held up for long periods of time
2332 		 * due to inefficiencies in other parts of the kernel,
2333 		 * certain video cards, etc.  Setting the FIFO trigger
2334 		 * point to MEDH instead of HIGH gives us 694uS of slop
2335 		 * (8 character times) instead of 173uS (2 character times)
2336 		 * @ 115200 bps.
2337 		 */
2338 		com->fifo_image = t->c_ospeed <= 4800
2339 				  ? FIFO_ENABLE : FIFO_ENABLE | FIFO_RX_MEDH;
2340 #ifdef COM_ESP
2341 		/*
2342 		 * The Hayes ESP card needs the fifo DMA mode bit set
2343 		 * in compatibility mode.  If not, it will interrupt
2344 		 * for each character received.
2345 		 */
2346 		if (com->esp)
2347 			com->fifo_image |= FIFO_DMA_MODE;
2348 #endif
2349 		sio_setreg(com, com_fifo, com->fifo_image);
2350 	}
2351 
2352 	/*
2353 	 * This returns with interrupts disabled so that we can complete
2354 	 * the speed change atomically.  Keeping interrupts disabled is
2355 	 * especially important while com_data is hidden.
2356 	 */
2357 	(void) siosetwater(com, t->c_ispeed);
2358 
2359 	if (divisor != 0) {
2360 		sio_setreg(com, com_cfcr, cfcr | CFCR_DLAB);
2361 		/*
2362 		 * Only set the divisor registers if they would change,
2363 		 * since on some 16550 incompatibles (UMC8669F), setting
2364 		 * them while input is arriving them loses sync until
2365 		 * data stops arriving.
2366 		 */
2367 		dlbl = divisor & 0xFF;
2368 		if (sio_getreg(com, com_dlbl) != dlbl)
2369 			sio_setreg(com, com_dlbl, dlbl);
2370 		dlbh = divisor >> 8;
2371 		if (sio_getreg(com, com_dlbh) != dlbh)
2372 			sio_setreg(com, com_dlbh, dlbh);
2373 	}
2374 
2375 	sio_setreg(com, com_cfcr, com->cfcr_image = cfcr);
2376 
2377 	if (!(tp->t_state & TS_TTSTOP))
2378 		com->state |= CS_TTGO;
2379 
2380 	if (cflag & CRTS_IFLOW) {
2381 		if (com->st16650a) {
2382 			sio_setreg(com, com_cfcr, 0xbf);
2383 			sio_setreg(com, com_fifo,
2384 				   sio_getreg(com, com_fifo) | 0x40);
2385 		}
2386 		com->state |= CS_RTS_IFLOW;
2387 		/*
2388 		 * If CS_RTS_IFLOW just changed from off to on, the change
2389 		 * needs to be propagated to MCR_RTS.  This isn't urgent,
2390 		 * so do it later by calling comstart() instead of repeating
2391 		 * a lot of code from comstart() here.
2392 		 */
2393 	} else if (com->state & CS_RTS_IFLOW) {
2394 		com->state &= ~CS_RTS_IFLOW;
2395 		/*
2396 		 * CS_RTS_IFLOW just changed from on to off.  Force MCR_RTS
2397 		 * on here, since comstart() won't do it later.
2398 		 */
2399 		outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
2400 		if (com->st16650a) {
2401 			sio_setreg(com, com_cfcr, 0xbf);
2402 			sio_setreg(com, com_fifo,
2403 				   sio_getreg(com, com_fifo) & ~0x40);
2404 		}
2405 	}
2406 
2407 
2408 	/*
2409 	 * Set up state to handle output flow control.
2410 	 * XXX - worth handling MDMBUF (DCD) flow control at the lowest level?
2411 	 * Now has 10+ msec latency, while CTS flow has 50- usec latency.
2412 	 */
2413 	com->state |= CS_ODEVREADY;
2414 	com->state &= ~CS_CTS_OFLOW;
2415 	if (cflag & CCTS_OFLOW) {
2416 		com->state |= CS_CTS_OFLOW;
2417 		if (!(com->last_modem_status & MSR_CTS))
2418 			com->state &= ~CS_ODEVREADY;
2419 		if (com->st16650a) {
2420 			sio_setreg(com, com_cfcr, 0xbf);
2421 			sio_setreg(com, com_fifo,
2422 				   sio_getreg(com, com_fifo) | 0x80);
2423 		}
2424 	} else {
2425 		if (com->st16650a) {
2426 			sio_setreg(com, com_cfcr, 0xbf);
2427 			sio_setreg(com, com_fifo,
2428 				   sio_getreg(com, com_fifo) & ~0x80);
2429 		}
2430 	}
2431 
2432 	sio_setreg(com, com_cfcr, com->cfcr_image);
2433 
2434 	/* XXX shouldn't call functions while intrs are disabled. */
2435 	disc_optim(tp, t, com);
2436 	/*
2437 	 * Recover from fiddling with CS_TTGO.  We used to call siointr1()
2438 	 * unconditionally, but that defeated the careful discarding of
2439 	 * stale input in sioopen().
2440 	 */
2441 	if (com->state >= (CS_BUSY | CS_TTGO))
2442 		siointr1(com);
2443 
2444 	com_unlock();
2445 	crit_exit();
2446 	comstart(tp);
2447 	if (com->ibufold != NULL) {
2448 		kfree(com->ibufold, M_DEVBUF);
2449 		com->ibufold = NULL;
2450 	}
2451 	lwkt_reltoken(&tty_token);
2452 	return (0);
2453 }
2454 
2455 static int
2456 siosetwater(struct com_s *com, speed_t speed)
2457 {
2458 	int		cp4ticks;
2459 	u_char		*ibuf;
2460 	int		ibufsize;
2461 	struct tty	*tp;
2462 
2463 	lwkt_gettoken(&tty_token);
2464 	/*
2465 	 * Make the buffer size large enough to handle a softtty interrupt
2466 	 * latency of about 2 ticks without loss of throughput or data
2467 	 * (about 3 ticks if input flow control is not used or not honoured,
2468 	 * but a bit less for CS5-CS7 modes).
2469 	 */
2470 	cp4ticks = speed / 10 / hz * 4;
2471 	for (ibufsize = 128; ibufsize < cp4ticks;)
2472 		ibufsize <<= 1;
2473 	if (ibufsize == com->ibufsize) {
2474 		com_lock();
2475 		lwkt_reltoken(&tty_token);
2476 		return (0);
2477 	}
2478 
2479 	/*
2480 	 * Allocate input buffer.  The extra factor of 2 in the size is
2481 	 * to allow for an error byte for each input byte.
2482 	 */
2483 	ibuf = kmalloc(2 * ibufsize, M_DEVBUF, M_WAITOK | M_ZERO);
2484 
2485 	/* Initialize non-critical variables. */
2486 	com->ibufold = com->ibuf;
2487 	com->ibufsize = ibufsize;
2488 	tp = com->tp;
2489 	if (tp != NULL) {
2490 		tp->t_ififosize = 2 * ibufsize;
2491 		tp->t_ispeedwat = (speed_t)-1;
2492 		tp->t_ospeedwat = (speed_t)-1;
2493 	}
2494 
2495 	/*
2496 	 * Read current input buffer, if any.  Continue with interrupts
2497 	 * disabled.
2498 	 */
2499 	com_lock();
2500 	if (com->iptr != com->ibuf)
2501 		sioinput(com);
2502 
2503 	/*-
2504 	 * Initialize critical variables, including input buffer watermarks.
2505 	 * The external device is asked to stop sending when the buffer
2506 	 * exactly reaches high water, or when the high level requests it.
2507 	 * The high level is notified immediately (rather than at a later
2508 	 * clock tick) when this watermark is reached.
2509 	 * The buffer size is chosen so the watermark should almost never
2510 	 * be reached.
2511 	 * The low watermark is invisibly 0 since the buffer is always
2512 	 * emptied all at once.
2513 	 */
2514 	com->iptr = com->ibuf = ibuf;
2515 	com->ibufend = ibuf + ibufsize;
2516 	com->ierroff = ibufsize;
2517 	com->ihighwater = ibuf + 3 * ibufsize / 4;
2518 	lwkt_reltoken(&tty_token);
2519 	return (0);
2520 }
2521 
2522 static void
2523 comstart(struct tty *tp)
2524 {
2525 	struct com_s	*com;
2526 	int		unit;
2527 
2528 	lwkt_gettoken(&tty_token);
2529 	unit = DEV_TO_UNIT(tp->t_dev);
2530 	com = com_addr(unit);
2531 	if (com == NULL) {
2532 		lwkt_reltoken(&tty_token);
2533 		return;
2534 	}
2535 	crit_enter();
2536 	com_lock();
2537 	if (tp->t_state & TS_TTSTOP)
2538 		com->state &= ~CS_TTGO;
2539 	else
2540 		com->state |= CS_TTGO;
2541 	if (tp->t_state & TS_TBLOCK) {
2542 		if (com->mcr_image & MCR_RTS && com->state & CS_RTS_IFLOW)
2543 			outb(com->modem_ctl_port, com->mcr_image &= ~MCR_RTS);
2544 	} else {
2545 		if (!(com->mcr_image & MCR_RTS) && com->iptr < com->ihighwater
2546 		    && com->state & CS_RTS_IFLOW)
2547 			outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
2548 	}
2549 	com_unlock();
2550 	if (tp->t_state & (TS_TIMEOUT | TS_TTSTOP)) {
2551 		ttwwakeup(tp);
2552 		crit_exit();
2553 		lwkt_reltoken(&tty_token);
2554 		return;
2555 	}
2556 	if (tp->t_outq.c_cc != 0) {
2557 		struct lbq	*qp;
2558 		struct lbq	*next;
2559 
2560 		if (!com->obufs[0].l_queued) {
2561 			com->obufs[0].l_tail
2562 			    = com->obuf1 + q_to_b(&tp->t_outq, com->obuf1,
2563 						  sizeof com->obuf1);
2564 			com->obufs[0].l_next = NULL;
2565 			com->obufs[0].l_queued = TRUE;
2566 			com_lock();
2567 			if (com->state & CS_BUSY) {
2568 				qp = com->obufq.l_next;
2569 				while ((next = qp->l_next) != NULL)
2570 					qp = next;
2571 				qp->l_next = &com->obufs[0];
2572 			} else {
2573 				com->obufq.l_head = com->obufs[0].l_head;
2574 				com->obufq.l_tail = com->obufs[0].l_tail;
2575 				com->obufq.l_next = &com->obufs[0];
2576 				com->state |= CS_BUSY;
2577 			}
2578 			com_unlock();
2579 		}
2580 		if (tp->t_outq.c_cc != 0 && !com->obufs[1].l_queued) {
2581 			com->obufs[1].l_tail
2582 			    = com->obuf2 + q_to_b(&tp->t_outq, com->obuf2,
2583 						  sizeof com->obuf2);
2584 			com->obufs[1].l_next = NULL;
2585 			com->obufs[1].l_queued = TRUE;
2586 			com_lock();
2587 			if (com->state & CS_BUSY) {
2588 				qp = com->obufq.l_next;
2589 				while ((next = qp->l_next) != NULL)
2590 					qp = next;
2591 				qp->l_next = &com->obufs[1];
2592 			} else {
2593 				com->obufq.l_head = com->obufs[1].l_head;
2594 				com->obufq.l_tail = com->obufs[1].l_tail;
2595 				com->obufq.l_next = &com->obufs[1];
2596 				com->state |= CS_BUSY;
2597 			}
2598 			com_unlock();
2599 		}
2600 		tp->t_state |= TS_BUSY;
2601 	}
2602 	com_lock();
2603 	if (com->state >= (CS_BUSY | CS_TTGO))
2604 		siointr1(com);	/* fake interrupt to start output */
2605 	com_unlock();
2606 	ttwwakeup(tp);
2607 	crit_exit();
2608 	lwkt_reltoken(&tty_token);
2609 }
2610 
2611 static void
2612 comstop(struct tty *tp, int rw)
2613 {
2614 	struct com_s	*com;
2615 
2616 	lwkt_gettoken(&tty_token);
2617 	com = com_addr(DEV_TO_UNIT(tp->t_dev));
2618 	if (com == NULL || com->gone) {
2619 		lwkt_reltoken(&tty_token);
2620 		return;
2621 	}
2622 	com_lock();
2623 	if (rw & FWRITE) {
2624 		if (com->hasfifo)
2625 #ifdef COM_ESP
2626 		    /* XXX avoid h/w bug. */
2627 		    if (!com->esp)
2628 #endif
2629 			sio_setreg(com, com_fifo,
2630 				   FIFO_XMT_RST | com->fifo_image);
2631 		com->obufs[0].l_queued = FALSE;
2632 		com->obufs[1].l_queued = FALSE;
2633 		if (com->state & CS_ODONE)
2634 			com_events -= LOTS_OF_EVENTS;
2635 		com->state &= ~(CS_ODONE | CS_BUSY);
2636 		com->tp->t_state &= ~TS_BUSY;
2637 	}
2638 	if (rw & FREAD) {
2639 		if (com->hasfifo)
2640 #ifdef COM_ESP
2641 		    /* XXX avoid h/w bug. */
2642 		    if (!com->esp)
2643 #endif
2644 			sio_setreg(com, com_fifo,
2645 				   FIFO_RCV_RST | com->fifo_image);
2646 		com_events -= (com->iptr - com->ibuf);
2647 		com->iptr = com->ibuf;
2648 	}
2649 	com_unlock();
2650 	comstart(tp);
2651 	lwkt_reltoken(&tty_token);
2652 }
2653 
2654 static int
2655 commctl(struct com_s *com, int bits, int how)
2656 {
2657 	int	mcr;
2658 	int	msr;
2659 
2660 	lwkt_gettoken(&tty_token);
2661 	if (how == DMGET) {
2662 		bits = TIOCM_LE;	/* XXX - always enabled while open */
2663 		mcr = com->mcr_image;
2664 		if (mcr & MCR_DTR)
2665 			bits |= TIOCM_DTR;
2666 		if (mcr & MCR_RTS)
2667 			bits |= TIOCM_RTS;
2668 		msr = com->prev_modem_status;
2669 		if (msr & MSR_CTS)
2670 			bits |= TIOCM_CTS;
2671 		if (msr & MSR_DCD)
2672 			bits |= TIOCM_CD;
2673 		if (msr & MSR_DSR)
2674 			bits |= TIOCM_DSR;
2675 		/*
2676 		 * XXX - MSR_RI is naturally volatile, and we make MSR_TERI
2677 		 * more volatile by reading the modem status a lot.  Perhaps
2678 		 * we should latch both bits until the status is read here.
2679 		 */
2680 		if (msr & (MSR_RI | MSR_TERI))
2681 			bits |= TIOCM_RI;
2682 		lwkt_reltoken(&tty_token);
2683 		return (bits);
2684 	}
2685 	mcr = 0;
2686 	if (bits & TIOCM_DTR)
2687 		mcr |= MCR_DTR;
2688 	if (bits & TIOCM_RTS)
2689 		mcr |= MCR_RTS;
2690 	if (com->gone) {
2691 		lwkt_reltoken(&tty_token);
2692 		return(0);
2693 	}
2694 	com_lock();
2695 	switch (how) {
2696 	case DMSET:
2697 		outb(com->modem_ctl_port,
2698 		     com->mcr_image = mcr | (com->mcr_image & MCR_IENABLE));
2699 		break;
2700 	case DMBIS:
2701 		outb(com->modem_ctl_port, com->mcr_image |= mcr);
2702 		break;
2703 	case DMBIC:
2704 		outb(com->modem_ctl_port, com->mcr_image &= ~mcr);
2705 		break;
2706 	}
2707 	com_unlock();
2708 	lwkt_reltoken(&tty_token);
2709 	return (0);
2710 }
2711 
2712 /*
2713  * NOTE: Must be called with tty_token held
2714  */
2715 static void
2716 siosettimeout(void)
2717 {
2718 	struct com_s	*com;
2719 	bool_t		someopen;
2720 	int		unit;
2721 
2722 	ASSERT_LWKT_TOKEN_HELD(&tty_token);
2723 	/*
2724 	 * Set our timeout period to 1 second if no polled devices are open.
2725 	 * Otherwise set it to max(1/200, 1/hz).
2726 	 * Enable timeouts iff some device is open.
2727 	 */
2728 	callout_stop(&sio_timeout_handle);
2729 	sio_timeout = hz;
2730 	someopen = FALSE;
2731 	for (unit = 0; unit < sio_numunits; ++unit) {
2732 		com = com_addr(unit);
2733 		if (com != NULL && com->tp != NULL
2734 		    && com->tp->t_state & TS_ISOPEN && !com->gone) {
2735 			someopen = TRUE;
2736 			if (com->poll || com->poll_output) {
2737 				sio_timeout = hz > 200 ? hz / 200 : 1;
2738 				break;
2739 			}
2740 		}
2741 	}
2742 	if (someopen) {
2743 		sio_timeouts_until_log = hz / sio_timeout;
2744 		callout_reset(&sio_timeout_handle, sio_timeout,
2745 				comwakeup, NULL);
2746 	} else {
2747 		/* Flush error messages, if any. */
2748 		sio_timeouts_until_log = 1;
2749 		comwakeup(NULL);
2750 		callout_stop(&sio_timeout_handle);
2751 	}
2752 }
2753 
2754 /*
2755  * NOTE: Must be called with tty_token held
2756  */
2757 static void
2758 comwakeup(void *chan)
2759 {
2760 	struct com_s	*com;
2761 	int		unit;
2762 
2763 	/*
2764 	 * Can be called from a callout too so just get the token
2765 	 */
2766 	lwkt_gettoken(&tty_token);
2767 	callout_reset(&sio_timeout_handle, sio_timeout, comwakeup, NULL);
2768 
2769 	/*
2770 	 * Recover from lost output interrupts.
2771 	 * Poll any lines that don't use interrupts.
2772 	 */
2773 	for (unit = 0; unit < sio_numunits; ++unit) {
2774 		com = com_addr(unit);
2775 		if (com != NULL && !com->gone
2776 		    && (com->state >= (CS_BUSY | CS_TTGO) || com->poll)) {
2777 			com_lock();
2778 			siointr1(com);
2779 			com_unlock();
2780 		}
2781 	}
2782 
2783 	/*
2784 	 * Check for and log errors, but not too often.
2785 	 */
2786 	if (--sio_timeouts_until_log > 0) {
2787 		lwkt_gettoken(&tty_token);
2788 		return;
2789 	}
2790 	sio_timeouts_until_log = hz / sio_timeout;
2791 	for (unit = 0; unit < sio_numunits; ++unit) {
2792 		int	errnum;
2793 
2794 		com = com_addr(unit);
2795 		if (com == NULL)
2796 			continue;
2797 		if (com->gone)
2798 			continue;
2799 		for (errnum = 0; errnum < CE_NTYPES; ++errnum) {
2800 			u_int	delta;
2801 			u_long	total;
2802 
2803 			com_lock();
2804 			delta = com->delta_error_counts[errnum];
2805 			com->delta_error_counts[errnum] = 0;
2806 			com_unlock();
2807 			if (delta == 0)
2808 				continue;
2809 			total = com->error_counts[errnum] += delta;
2810 			log(LOG_ERR, "sio%d: %u more %s%s (total %lu)\n",
2811 			    unit, delta, error_desc[errnum],
2812 			    delta == 1 ? "" : "s", total);
2813 		}
2814 	}
2815 	lwkt_reltoken(&tty_token);
2816 }
2817 
2818 static void
2819 disc_optim(struct tty *tp, struct termios *t, struct com_s *com)
2820 {
2821 	lwkt_gettoken(&tty_token);
2822 	if (!(t->c_iflag & (ICRNL | IGNCR | IMAXBEL | INLCR | ISTRIP | IXON))
2823 	    && (!(t->c_iflag & BRKINT) || (t->c_iflag & IGNBRK))
2824 	    && (!(t->c_iflag & PARMRK)
2825 		|| (t->c_iflag & (IGNPAR | IGNBRK)) == (IGNPAR | IGNBRK))
2826 	    && !(t->c_lflag & (ECHO | ICANON | IEXTEN | ISIG | PENDIN))
2827 	    && linesw[tp->t_line].l_rint == ttyinput)
2828 		tp->t_state |= TS_CAN_BYPASS_L_RINT;
2829 	else
2830 		tp->t_state &= ~TS_CAN_BYPASS_L_RINT;
2831 	com->hotchar = linesw[tp->t_line].l_hotchar;
2832 	lwkt_reltoken(&tty_token);
2833 }
2834 
2835 /*
2836  * Following are all routines needed for SIO to act as console
2837  */
2838 #include <sys/cons.h>
2839 
2840 struct siocnstate {
2841 	u_char	dlbl;
2842 	u_char	dlbh;
2843 	u_char	ier;
2844 	u_char	cfcr;
2845 	u_char	mcr;
2846 };
2847 
2848 static speed_t siocngetspeed (Port_t, u_long rclk);
2849 static void siocnclose	(struct siocnstate *sp, Port_t iobase);
2850 static void siocnopen	(struct siocnstate *sp, Port_t iobase, int speed);
2851 static void siocntxwait	(Port_t iobase);
2852 
2853 static cn_probe_t siocnprobe;
2854 static cn_init_t siocninit;
2855 static cn_init_fini_t siocninit_fini;
2856 static cn_checkc_t siocncheckc;
2857 static cn_getc_t siocngetc;
2858 static cn_putc_t siocnputc;
2859 
2860 #if defined(__i386__) || defined(__x86_64__)
2861 CONS_DRIVER(sio, siocnprobe, siocninit, siocninit_fini,
2862 	    NULL, siocngetc, siocncheckc, siocnputc, NULL);
2863 #endif
2864 
2865 /* To get the GDB related variables */
2866 #if DDB > 0
2867 #include <ddb/ddb.h>
2868 #endif
2869 
2870 /*
2871  * NOTE: Must be called with tty_token held
2872  */
2873 static void
2874 siocntxwait(Port_t iobase)
2875 {
2876 	int	timo;
2877 
2878 	ASSERT_LWKT_TOKEN_HELD(&tty_token);
2879 	/*
2880 	 * Wait for any pending transmission to finish.  Required to avoid
2881 	 * the UART lockup bug when the speed is changed, and for normal
2882 	 * transmits.
2883 	 */
2884 	timo = 100000;
2885 	while ((inb(iobase + com_lsr) & (LSR_TSRE | LSR_TXRDY))
2886 	       != (LSR_TSRE | LSR_TXRDY) && --timo != 0)
2887 		;
2888 }
2889 
2890 /*
2891  * Read the serial port specified and try to figure out what speed
2892  * it's currently running at.  We're assuming the serial port has
2893  * been initialized and is basicly idle.  This routine is only intended
2894  * to be run at system startup.
2895  *
2896  * If the value read from the serial port doesn't make sense, return 0.
2897  */
2898 /*
2899  * NOTE: Must be called with tty_token held
2900  */
2901 static speed_t
2902 siocngetspeed(Port_t iobase, u_long rclk)
2903 {
2904 	u_int	divisor;
2905 	u_char	dlbh;
2906 	u_char	dlbl;
2907 	u_char  cfcr;
2908 
2909 	ASSERT_LWKT_TOKEN_HELD(&tty_token);
2910 	cfcr = inb(iobase + com_cfcr);
2911 	outb(iobase + com_cfcr, CFCR_DLAB | cfcr);
2912 
2913 	dlbl = inb(iobase + com_dlbl);
2914 	dlbh = inb(iobase + com_dlbh);
2915 
2916 	outb(iobase + com_cfcr, cfcr);
2917 
2918 	divisor = dlbh << 8 | dlbl;
2919 
2920 	/* XXX there should be more sanity checking. */
2921 	if (divisor == 0)
2922 		return (CONSPEED);
2923 	return (rclk / (16UL * divisor));
2924 }
2925 
2926 static void
2927 siocnopen(struct siocnstate *sp, Port_t iobase, int speed)
2928 {
2929 	u_int	divisor;
2930 	u_char	dlbh;
2931 	u_char	dlbl;
2932 
2933 	lwkt_gettoken(&tty_token);
2934 	/*
2935 	 * Save all the device control registers except the fifo register
2936 	 * and set our default ones (cs8 -parenb speed=comdefaultrate).
2937 	 * We can't save the fifo register since it is read-only.
2938 	 */
2939 	sp->ier = inb(iobase + com_ier);
2940 	outb(iobase + com_ier, 0);	/* spltty() doesn't stop siointr() */
2941 	siocntxwait(iobase);
2942 	sp->cfcr = inb(iobase + com_cfcr);
2943 	outb(iobase + com_cfcr, CFCR_DLAB | CFCR_8BITS);
2944 	sp->dlbl = inb(iobase + com_dlbl);
2945 	sp->dlbh = inb(iobase + com_dlbh);
2946 	/*
2947 	 * Only set the divisor registers if they would change, since on
2948 	 * some 16550 incompatibles (Startech), setting them clears the
2949 	 * data input register.  This also reduces the effects of the
2950 	 * UMC8669F bug.
2951 	 */
2952 	divisor = siodivisor(comdefaultrclk, speed);
2953 	dlbl = divisor & 0xFF;
2954 	if (sp->dlbl != dlbl)
2955 		outb(iobase + com_dlbl, dlbl);
2956 	dlbh = divisor >> 8;
2957 	if (sp->dlbh != dlbh)
2958 		outb(iobase + com_dlbh, dlbh);
2959 	outb(iobase + com_cfcr, CFCR_8BITS);
2960 	sp->mcr = inb(iobase + com_mcr);
2961 	/*
2962 	 * We don't want interrupts, but must be careful not to "disable"
2963 	 * them by clearing the MCR_IENABLE bit, since that might cause
2964 	 * an interrupt by floating the IRQ line.
2965 	 */
2966 	outb(iobase + com_mcr, (sp->mcr & MCR_IENABLE) | MCR_DTR | MCR_RTS);
2967 	lwkt_reltoken(&tty_token);
2968 }
2969 
2970 static void
2971 siocnclose(struct siocnstate *sp, Port_t iobase)
2972 {
2973 	lwkt_gettoken(&tty_token);
2974 	/*
2975 	 * Restore the device control registers.
2976 	 */
2977 	siocntxwait(iobase);
2978 	outb(iobase + com_cfcr, CFCR_DLAB | CFCR_8BITS);
2979 	if (sp->dlbl != inb(iobase + com_dlbl))
2980 		outb(iobase + com_dlbl, sp->dlbl);
2981 	if (sp->dlbh != inb(iobase + com_dlbh))
2982 		outb(iobase + com_dlbh, sp->dlbh);
2983 	outb(iobase + com_cfcr, sp->cfcr);
2984 	/*
2985 	 * XXX damp oscillations of MCR_DTR and MCR_RTS by not restoring them.
2986 	 */
2987 	outb(iobase + com_mcr, sp->mcr | MCR_DTR | MCR_RTS);
2988 	outb(iobase + com_ier, sp->ier);
2989 	lwkt_reltoken(&tty_token);
2990 }
2991 
2992 static void
2993 siocnprobe(struct consdev *cp)
2994 {
2995 	speed_t			boot_speed;
2996 	u_char			cfcr;
2997 	u_int			divisor;
2998 	int			unit;
2999 	struct siocnstate	sp;
3000 
3001 	/*
3002 	 * Find our first enabled console, if any.  If it is a high-level
3003 	 * console device, then initialize it and return successfully.
3004 	 * If it is a low-level console device, then initialize it and
3005 	 * return unsuccessfully.  It must be initialized in both cases
3006 	 * for early use by console drivers and debuggers.  Initializing
3007 	 * the hardware is not necessary in all cases, since the i/o
3008 	 * routines initialize it on the fly, but it is necessary if
3009 	 * input might arrive while the hardware is switched back to an
3010 	 * uninitialized state.  We can't handle multiple console devices
3011 	 * yet because our low-level routines don't take a device arg.
3012 	 * We trust the user to set the console flags properly so that we
3013 	 * don't need to probe.
3014 	 */
3015 	cp->cn_pri = CN_DEAD;
3016 
3017 	lwkt_gettoken(&tty_token);
3018 	for (unit = 0; unit < 16; unit++) { /* XXX need to know how many */
3019 		int flags;
3020 		int disabled;
3021 		if (resource_int_value("sio", unit, "disabled", &disabled) == 0) {
3022 			if (disabled)
3023 				continue;
3024 		}
3025 		if (resource_int_value("sio", unit, "flags", &flags))
3026 			continue;
3027 		if (COM_CONSOLE(flags) || COM_DEBUGGER(flags)) {
3028 			int port;
3029 			Port_t iobase;
3030 
3031 			if (resource_int_value("sio", unit, "port", &port))
3032 				continue;
3033 			iobase = port;
3034 			crit_enter();
3035 			if (boothowto & RB_SERIAL) {
3036 				boot_speed =
3037 				    siocngetspeed(iobase, comdefaultrclk);
3038 				if (boot_speed)
3039 					comdefaultrate = boot_speed;
3040 			}
3041 
3042 			/*
3043 			 * Initialize the divisor latch.  We can't rely on
3044 			 * siocnopen() to do this the first time, since it
3045 			 * avoids writing to the latch if the latch appears
3046 			 * to have the correct value.  Also, if we didn't
3047 			 * just read the speed from the hardware, then we
3048 			 * need to set the speed in hardware so that
3049 			 * switching it later is null.
3050 			 */
3051 			cfcr = inb(iobase + com_cfcr);
3052 			outb(iobase + com_cfcr, CFCR_DLAB | cfcr);
3053 			divisor = siodivisor(comdefaultrclk, comdefaultrate);
3054 			outb(iobase + com_dlbl, divisor & 0xff);
3055 			outb(iobase + com_dlbh, divisor >> 8);
3056 			outb(iobase + com_cfcr, cfcr);
3057 
3058 			siocnopen(&sp, iobase, comdefaultrate);
3059 
3060 			crit_exit();
3061 			if (COM_CONSOLE(flags) && !COM_LLCONSOLE(flags)) {
3062 				cp->cn_probegood = 1;
3063 				cp->cn_private = (void *)(intptr_t)unit;
3064 				cp->cn_pri = COM_FORCECONSOLE(flags)
3065 					     || boothowto & RB_SERIAL
3066 					     ? CN_REMOTE : CN_NORMAL;
3067 				siocniobase = iobase;
3068 				siocnunit = unit;
3069 			}
3070 			if (COM_DEBUGGER(flags) && gdb_tab == NULL) {
3071 				kprintf("sio%d: gdb debugging port\n", unit);
3072 				siogdbiobase = iobase;
3073 				siogdbunit = unit;
3074 #if DDB > 0
3075 				cp->cn_gdbprivate = (void *)(intptr_t)unit;
3076 				gdb_tab = cp;
3077 #endif
3078 			}
3079 		}
3080 	}
3081 #if defined(__i386__) || defined(__x86_64__)
3082 #if DDB > 0
3083 	/*
3084 	 * XXX Ugly Compatability.
3085 	 * If no gdb port has been specified, set it to be the console
3086 	 * as some configuration files don't specify the gdb port.
3087 	 */
3088 	if (gdb_tab == NULL && (boothowto & RB_GDB)) {
3089 		kprintf("Warning: no GDB port specified. Defaulting to sio%d.\n",
3090 			siocnunit);
3091 		kprintf("Set flag 0x80 on desired GDB port in your\n");
3092 		kprintf("configuration file (currently sio only).\n");
3093 		siogdbiobase = siocniobase;
3094 		siogdbunit = siocnunit;
3095 		cp->cn_gdbprivate = (void *)(intptr_t)siocnunit;
3096 		gdb_tab = cp;
3097 	}
3098 #endif
3099 #endif
3100 	lwkt_reltoken(&tty_token);
3101 }
3102 
3103 static void
3104 siocninit(struct consdev *cp)
3105 {
3106 	comconsole = (int)(intptr_t)cp->cn_private;
3107 }
3108 
3109 static void
3110 siocninit_fini(struct consdev *cp)
3111 {
3112 	cdev_t dev;
3113 	int unit;
3114 
3115 	if (cp->cn_probegood) {
3116 		unit = (int)(intptr_t)cp->cn_private;
3117 		/*
3118 		 * Call devfs_find_device_by_name on ttydX to find the correct device,
3119 		 * as it should have been created already at this point by the
3120 		 * attach routine.
3121 		 * If it isn't found, the serial port was not attached at all and we
3122 		 * shouldn't be here, so assert this case.
3123 		 */
3124 		dev = devfs_find_device_by_name("ttyd%r", unit);
3125 
3126 		KKASSERT(dev != NULL);
3127 		cp->cn_dev = dev;
3128 	}
3129 }
3130 
3131 static int
3132 siocncheckc(void *private)
3133 {
3134 	int	c;
3135 	int	unit = (int)(intptr_t)private;
3136 	Port_t	iobase;
3137 	struct siocnstate	sp;
3138 
3139 	lwkt_gettoken(&tty_token);
3140 	if (unit == siogdbunit)
3141 		iobase = siogdbiobase;
3142 	else
3143 		iobase = siocniobase;
3144 	crit_enter();
3145 	siocnopen(&sp, iobase, comdefaultrate);
3146 	if (inb(iobase + com_lsr) & LSR_RXRDY)
3147 		c = inb(iobase + com_data);
3148 	else
3149 		c = -1;
3150 	siocnclose(&sp, iobase);
3151 	crit_exit();
3152 	lwkt_reltoken(&tty_token);
3153 	return (c);
3154 }
3155 
3156 
3157 int
3158 siocngetc(void *private)
3159 {
3160 	int	c;
3161 	int	unit = (int)(intptr_t)private;
3162 	Port_t	iobase;
3163 	struct siocnstate	sp;
3164 
3165 	lwkt_gettoken(&tty_token);
3166 	if (unit == siogdbunit)
3167 		iobase = siogdbiobase;
3168 	else
3169 		iobase = siocniobase;
3170 	crit_enter();
3171 	siocnopen(&sp, iobase, comdefaultrate);
3172 	while (!(inb(iobase + com_lsr) & LSR_RXRDY))
3173 		;
3174 	c = inb(iobase + com_data);
3175 	siocnclose(&sp, iobase);
3176 	crit_exit();
3177 	lwkt_reltoken(&tty_token);
3178 	return (c);
3179 }
3180 
3181 void
3182 siocnputc(void *private, int c)
3183 {
3184 	int	unit = (int)(intptr_t)private;
3185 	struct siocnstate	sp;
3186 	Port_t	iobase;
3187 
3188 	lwkt_gettoken(&tty_token);
3189 	if (unit == siogdbunit)
3190 		iobase = siogdbiobase;
3191 	else
3192 		iobase = siocniobase;
3193 	crit_enter();
3194 	siocnopen(&sp, iobase, comdefaultrate);
3195 	siocntxwait(iobase);
3196 	outb(iobase + com_data, c);
3197 	siocnclose(&sp, iobase);
3198 	crit_exit();
3199 	lwkt_reltoken(&tty_token);
3200 }
3201 
3202 DRIVER_MODULE(sio, isa, sio_isa_driver, sio_devclass, 0, 0);
3203 DRIVER_MODULE(sio, acpi, sio_isa_driver, sio_devclass, 0, 0);
3204 #if NPCI > 0
3205 DRIVER_MODULE(sio, pci, sio_pci_driver, sio_devclass, 0, 0);
3206 #endif
3207 #if NPUC > 0
3208 DRIVER_MODULE(sio, puc, sio_puc_driver, sio_devclass, 0, 0);
3209 #endif
3210