xref: /dragonfly/sys/dev/serial/sio/sio.c (revision 8a0bcd56)
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 		com_unlock();
735 		lwkt_reltoken(&tty_token);
736 		kprintf("sio%d: can't drain, serial port might "
737 			"not exist, disabling\n", device_get_unit(dev));
738 		return (ENXIO);
739 	}
740 
741 	/*
742 	 * Enable the interrupt gate and disable device interupts.  This
743 	 * should leave the device driving the interrupt line low and
744 	 * guarantee an edge trigger if an interrupt can be generated.
745 	 */
746 /* EXTRA DELAY? */
747 	sio_setreg(com, com_mcr, mcr_image);
748 	sio_setreg(com, com_ier, 0);
749 	DELAY(1000);		/* XXX */
750 	irqmap[0] = isa_irq_pending();
751 
752 	/*
753 	 * Attempt to set loopback mode so that we can send a null byte
754 	 * without annoying any external device.
755 	 */
756 /* EXTRA DELAY? */
757 	sio_setreg(com, com_mcr, mcr_image | MCR_LOOPBACK);
758 
759 	/*
760 	 * Attempt to generate an output interrupt.  On 8250's, setting
761 	 * IER_ETXRDY generates an interrupt independent of the current
762 	 * setting and independent of whether the THR is empty.  On 16450's,
763 	 * setting IER_ETXRDY generates an interrupt independent of the
764 	 * current setting.  On 16550A's, setting IER_ETXRDY only
765 	 * generates an interrupt when IER_ETXRDY is not already set.
766 	 */
767 	sio_setreg(com, com_ier, IER_ETXRDY);
768 
769 	/*
770 	 * On some 16x50 incompatibles, setting IER_ETXRDY doesn't generate
771 	 * an interrupt.  They'd better generate one for actually doing
772 	 * output.  Loopback may be broken on the same incompatibles but
773 	 * it's unlikely to do more than allow the null byte out.
774 	 */
775 	sio_setreg(com, com_data, 0);
776 	DELAY((1 + 2) * 1000000 / (SIO_TEST_SPEED / 10));
777 
778 	/*
779 	 * Turn off loopback mode so that the interrupt gate works again
780 	 * (MCR_IENABLE was hidden).  This should leave the device driving
781 	 * an interrupt line high.  It doesn't matter if the interrupt
782 	 * line oscillates while we are not looking at it, since interrupts
783 	 * are disabled.
784 	 */
785 /* EXTRA DELAY? */
786 	sio_setreg(com, com_mcr, mcr_image);
787 
788 	/*
789 	 * Some pcmcia cards have the "TXRDY bug", so we check everyone
790 	 * for IIR_TXRDY implementation ( Palido 321s, DC-1S... )
791 	 */
792 	if (COM_NOPROBE(flags)) {
793 		/* Reading IIR register twice */
794 		for (fn = 0; fn < 2; fn ++) {
795 			DELAY(10000);
796 			failures[6] = sio_getreg(com, com_iir);
797 		}
798 		/* Check IIR_TXRDY clear ? */
799 		result = 0;
800 		if (failures[6] & IIR_TXRDY) {
801 			/* Nop, Double check with clearing IER */
802 			sio_setreg(com, com_ier, 0);
803 			if (sio_getreg(com, com_iir) & IIR_NOPEND) {
804 				/* Ok. we're familia this gang */
805 				SET_FLAG(dev, COM_C_IIR_TXRDYBUG);
806 			} else {
807 				/* Unknown, Just omit this chip.. XXX */
808 				result = ENXIO;
809 				sio_setreg(com, com_mcr, 0);
810 			}
811 		} else {
812 			/* OK. this is well-known guys */
813 			CLR_FLAG(dev, COM_C_IIR_TXRDYBUG);
814 		}
815 		sio_setreg(com, com_ier, 0);
816 		sio_setreg(com, com_cfcr, CFCR_8BITS);
817 		com_unlock();
818 		bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
819 		lwkt_reltoken(&tty_token);
820 		return (iobase == siocniobase ? 0 : result);
821 	}
822 
823 	/*
824 	 * Check that
825 	 *	o the CFCR, IER and MCR in UART hold the values written to them
826 	 *	  (the values happen to be all distinct - this is good for
827 	 *	  avoiding false positive tests from bus echoes).
828 	 *	o an output interrupt is generated and its vector is correct.
829 	 *	o the interrupt goes away when the IIR in the UART is read.
830 	 */
831 /* EXTRA DELAY? */
832 	failures[0] = sio_getreg(com, com_cfcr) - CFCR_8BITS;
833 	failures[1] = sio_getreg(com, com_ier) - IER_ETXRDY;
834 	failures[2] = sio_getreg(com, com_mcr) - mcr_image;
835 	DELAY(10000);		/* Some internal modems need this time */
836 	irqmap[1] = isa_irq_pending();
837 	failures[4] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_TXRDY;
838 	DELAY(1000);		/* XXX */
839 	irqmap[2] = isa_irq_pending();
840 	failures[6] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_NOPEND;
841 
842 	/*
843 	 * Turn off all device interrupts and check that they go off properly.
844 	 * Leave MCR_IENABLE alone.  For ports without a master port, it gates
845 	 * the OUT2 output of the UART to
846 	 * the ICU input.  Closing the gate would give a floating ICU input
847 	 * (unless there is another device driving it) and spurious interrupts.
848 	 * (On the system that this was first tested on, the input floats high
849 	 * and gives a (masked) interrupt as soon as the gate is closed.)
850 	 */
851 	sio_setreg(com, com_ier, 0);
852 	sio_setreg(com, com_cfcr, CFCR_8BITS);	/* dummy to avoid bus echo */
853 	failures[7] = sio_getreg(com, com_ier);
854 	DELAY(1000);		/* XXX */
855 	irqmap[3] = isa_irq_pending();
856 	failures[9] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_NOPEND;
857 
858 	com_unlock();
859 
860 	irqs = irqmap[1] & ~irqmap[0];
861 	if (bus_get_resource(idev, SYS_RES_IRQ, 0, &xirq, NULL) == 0 &&
862 	    ((1 << xirq) & irqs) == 0)
863 		kprintf(
864 		"sio%d: configured irq %ld not in bitmap of probed irqs %#x\n",
865 		    device_get_unit(dev), xirq, irqs);
866 	if (bootverbose)
867 		kprintf("sio%d: irq maps: %#x %#x %#x %#x\n",
868 		    device_get_unit(dev),
869 		    irqmap[0], irqmap[1], irqmap[2], irqmap[3]);
870 
871 	result = 0;
872 	for (fn = 0; fn < sizeof failures; ++fn)
873 		if (failures[fn]) {
874 			sio_setreg(com, com_mcr, 0);
875 			result = ENXIO;
876 			if (bootverbose) {
877 				kprintf("sio%d: probe failed test(s):",
878 				    device_get_unit(dev));
879 				for (fn = 0; fn < sizeof failures; ++fn)
880 					if (failures[fn])
881 						kprintf(" %d", fn);
882 				kprintf("\n");
883 			}
884 			break;
885 		}
886 	bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
887 	lwkt_reltoken(&tty_token);
888 	return (iobase == siocniobase ? 0 : result);
889 }
890 
891 #ifdef COM_ESP
892 static int
893 espattach(struct com_s *com, Port_t esp_port)
894 {
895 	u_char	dips;
896 	u_char	val;
897 
898 	/*
899 	 * Check the ESP-specific I/O port to see if we're an ESP
900 	 * card.  If not, return failure immediately.
901 	 */
902 	if ((inb(esp_port) & 0xf3) == 0) {
903 		kprintf(" port 0x%x is not an ESP board?\n", esp_port);
904 		return (0);
905 	}
906 
907 	lwkt_gettoken(&tty_token);
908 	/*
909 	 * We've got something that claims to be a Hayes ESP card.
910 	 * Let's hope so.
911 	 */
912 
913 	/* Get the dip-switch configuration */
914 	outb(esp_port + ESP_CMD1, ESP_GETDIPS);
915 	dips = inb(esp_port + ESP_STATUS1);
916 
917 	/*
918 	 * Bits 0,1 of dips say which COM port we are.
919 	 */
920 	if (rman_get_start(com->ioportres) == likely_com_ports[dips & 0x03])
921 		kprintf(" : ESP");
922 	else {
923 		kprintf(" esp_port has com %d\n", dips & 0x03);
924 		lwkt_reltoken(&tty_token);
925 		return (0);
926 	}
927 
928 	/*
929 	 * Check for ESP version 2.0 or later:  bits 4,5,6 = 010.
930 	 */
931 	outb(esp_port + ESP_CMD1, ESP_GETTEST);
932 	val = inb(esp_port + ESP_STATUS1);	/* clear reg 1 */
933 	val = inb(esp_port + ESP_STATUS2);
934 	if ((val & 0x70) < 0x20) {
935 		kprintf("-old (%o)", val & 0x70);
936 		lwkt_reltoken(&tty_token);
937 		return (0);
938 	}
939 
940 	/*
941 	 * Check for ability to emulate 16550:  bit 7 == 1
942 	 */
943 	if ((dips & 0x80) == 0) {
944 		kprintf(" slave");
945 		lwkt_reltoken(&tty_token);
946 		return (0);
947 	}
948 
949 	/*
950 	 * Okay, we seem to be a Hayes ESP card.  Whee.
951 	 */
952 	com->esp = TRUE;
953 	com->esp_port = esp_port;
954 	lwkt_reltoken(&tty_token);
955 	return (1);
956 }
957 #endif /* COM_ESP */
958 
959 static int
960 sio_isa_attach(device_t dev)
961 {
962 	return (sioattach(dev, 0, 0UL));
963 }
964 
965 int
966 sioattach(device_t dev, int xrid, u_long rclk)
967 {
968 	struct com_s	*com;
969 #ifdef COM_ESP
970 	Port_t		*espp;
971 #endif
972 	Port_t		iobase;
973 	int		minorbase;
974 	int		unit;
975 	u_int		flags;
976 	int		rid;
977 	struct resource *port;
978 	int		ret;
979 	static int	did_init;
980 
981 	lwkt_gettoken(&tty_token);
982 	if (did_init == 0) {
983 		did_init = 1;
984 		callout_init_mp(&sio_timeout_handle);
985 	}
986 
987 	rid = xrid;
988 	port = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid,
989 				  0, ~0, IO_COMSIZE, RF_ACTIVE);
990 	if (!port) {
991 		lwkt_reltoken(&tty_token);
992 		return (ENXIO);
993 	}
994 
995 	iobase = rman_get_start(port);
996 	unit = device_get_unit(dev);
997 	com = device_get_softc(dev);
998 	flags = device_get_flags(dev);
999 
1000 	if (unit >= sio_numunits)
1001 		sio_numunits = unit + 1;
1002 	/*
1003 	 * sioprobe() has initialized the device registers as follows:
1004 	 *	o cfcr = CFCR_8BITS.
1005 	 *	  It is most important that CFCR_DLAB is off, so that the
1006 	 *	  data port is not hidden when we enable interrupts.
1007 	 *	o ier = 0.
1008 	 *	  Interrupts are only enabled when the line is open.
1009 	 *	o mcr = MCR_IENABLE, or 0 if the port has AST/4 compatible
1010 	 *	  interrupt control register or the config specifies no irq.
1011 	 *	  Keeping MCR_DTR and MCR_RTS off might stop the external
1012 	 *	  device from sending before we are ready.
1013 	 */
1014 	bzero(com, sizeof *com);
1015 	com->unit = unit;
1016 	com->ioportres = port;
1017 	com->bst = rman_get_bustag(port);
1018 	com->bsh = rman_get_bushandle(port);
1019 	com->cfcr_image = CFCR_8BITS;
1020 	com->dtr_wait = 3 * hz;
1021 	callout_init_mp(&com->dtr_ch);
1022 	callout_init_mp(&com->busy_ch);
1023 	com->loses_outints = COM_LOSESOUTINTS(flags) != 0;
1024 	com->no_irq = bus_get_resource(dev, SYS_RES_IRQ, 0, NULL, NULL) != 0;
1025 	com->tx_fifo_size = 1;
1026 	com->obufs[0].l_head = com->obuf1;
1027 	com->obufs[1].l_head = com->obuf2;
1028 
1029 	com->data_port = iobase + com_data;
1030 	com->int_id_port = iobase + com_iir;
1031 	com->modem_ctl_port = iobase + com_mcr;
1032 	com->mcr_image = inb(com->modem_ctl_port);
1033 	com->line_status_port = iobase + com_lsr;
1034 	com->modem_status_port = iobase + com_msr;
1035 	com->intr_ctl_port = iobase + com_ier;
1036 
1037 	if (rclk == 0)
1038 		rclk = DEFAULT_RCLK;
1039 	com->rclk = rclk;
1040 
1041 	/*
1042 	 * We don't use all the flags from <sys/ttydefaults.h> since they
1043 	 * are only relevant for logins.  It's important to have echo off
1044 	 * initially so that the line doesn't start blathering before the
1045 	 * echo flag can be turned off.
1046 	 */
1047 	com->it_in.c_iflag = 0;
1048 	com->it_in.c_oflag = 0;
1049 	com->it_in.c_cflag = TTYDEF_CFLAG;
1050 	com->it_in.c_lflag = 0;
1051 	if (unit == comconsole) {
1052 		com->it_in.c_iflag = TTYDEF_IFLAG;
1053 		com->it_in.c_oflag = TTYDEF_OFLAG;
1054 		com->it_in.c_cflag = TTYDEF_CFLAG | CLOCAL;
1055 		com->it_in.c_lflag = TTYDEF_LFLAG;
1056 		com->lt_out.c_cflag = com->lt_in.c_cflag = CLOCAL;
1057 		com->lt_out.c_ispeed = com->lt_out.c_ospeed =
1058 		com->lt_in.c_ispeed = com->lt_in.c_ospeed =
1059 		com->it_in.c_ispeed = com->it_in.c_ospeed = comdefaultrate;
1060 	} else
1061 		com->it_in.c_ispeed = com->it_in.c_ospeed = TTYDEF_SPEED;
1062 	if (siosetwater(com, com->it_in.c_ispeed) != 0) {
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 	termioschars(&com->it_in);
1073 	com->it_out = com->it_in;
1074 
1075 	/* attempt to determine UART type */
1076 	kprintf("sio%d: type", unit);
1077 
1078 
1079 #ifdef COM_MULTIPORT
1080 	if (!COM_ISMULTIPORT(flags) && !COM_IIR_TXRDYBUG(flags))
1081 #else
1082 	if (!COM_IIR_TXRDYBUG(flags))
1083 #endif
1084 	{
1085 		u_char	scr;
1086 		u_char	scr1;
1087 		u_char	scr2;
1088 
1089 		scr = sio_getreg(com, com_scr);
1090 		sio_setreg(com, com_scr, 0xa5);
1091 		scr1 = sio_getreg(com, com_scr);
1092 		sio_setreg(com, com_scr, 0x5a);
1093 		scr2 = sio_getreg(com, com_scr);
1094 		sio_setreg(com, com_scr, scr);
1095 		if (scr1 != 0xa5 || scr2 != 0x5a) {
1096 			kprintf(" 8250");
1097 			goto determined_type;
1098 		}
1099 	}
1100 	sio_setreg(com, com_fifo, FIFO_ENABLE | FIFO_RX_HIGH);
1101 	DELAY(100);
1102 	com->st16650a = 0;
1103 	switch (inb(com->int_id_port) & IIR_FIFO_MASK) {
1104 	case FIFO_RX_LOW:
1105 		kprintf(" 16450");
1106 		break;
1107 	case FIFO_RX_MEDL:
1108 		kprintf(" 16450?");
1109 		break;
1110 	case FIFO_RX_MEDH:
1111 		kprintf(" 16550?");
1112 		break;
1113 	case FIFO_RX_HIGH:
1114 		if (COM_NOFIFO(flags)) {
1115 			kprintf(" 16550A fifo disabled");
1116 		} else {
1117 			com->hasfifo = TRUE;
1118 			if (COM_ST16650A(flags)) {
1119 				com->st16650a = 1;
1120 				com->tx_fifo_size = 32;
1121 				kprintf(" ST16650A");
1122 			} else if (COM_TI16754(flags)) {
1123 				com->tx_fifo_size = 64;
1124 				kprintf(" TI16754");
1125 			} else {
1126 				com->tx_fifo_size = COM_FIFOSIZE(flags);
1127 				kprintf(" 16550A");
1128 			}
1129 		}
1130 #ifdef COM_ESP
1131 		for (espp = likely_esp_ports; *espp != 0; espp++)
1132 			if (espattach(com, *espp)) {
1133 				com->tx_fifo_size = 1024;
1134 				break;
1135 			}
1136 #endif
1137 		if (!com->st16650a && !COM_TI16754(flags)) {
1138 			if (!com->tx_fifo_size)
1139 				com->tx_fifo_size = 16;
1140 			else
1141 				kprintf(" lookalike with %d bytes FIFO",
1142 				    com->tx_fifo_size);
1143 		}
1144 
1145 		break;
1146 	}
1147 
1148 #ifdef COM_ESP
1149 	if (com->esp) {
1150 		/*
1151 		 * Set 16550 compatibility mode.
1152 		 * We don't use the ESP_MODE_SCALE bit to increase the
1153 		 * fifo trigger levels because we can't handle large
1154 		 * bursts of input.
1155 		 * XXX flow control should be set in comparam(), not here.
1156 		 */
1157 		outb(com->esp_port + ESP_CMD1, ESP_SETMODE);
1158 		outb(com->esp_port + ESP_CMD2, ESP_MODE_RTS | ESP_MODE_FIFO);
1159 
1160 		/* Set RTS/CTS flow control. */
1161 		outb(com->esp_port + ESP_CMD1, ESP_SETFLOWTYPE);
1162 		outb(com->esp_port + ESP_CMD2, ESP_FLOW_RTS);
1163 		outb(com->esp_port + ESP_CMD2, ESP_FLOW_CTS);
1164 
1165 		/* Set flow-control levels. */
1166 		outb(com->esp_port + ESP_CMD1, ESP_SETRXFLOW);
1167 		outb(com->esp_port + ESP_CMD2, HIBYTE(768));
1168 		outb(com->esp_port + ESP_CMD2, LOBYTE(768));
1169 		outb(com->esp_port + ESP_CMD2, HIBYTE(512));
1170 		outb(com->esp_port + ESP_CMD2, LOBYTE(512));
1171 	}
1172 #endif /* COM_ESP */
1173 	sio_setreg(com, com_fifo, 0);
1174 determined_type: ;
1175 
1176 #ifdef COM_MULTIPORT
1177 	if (COM_ISMULTIPORT(flags)) {
1178 		device_t masterdev;
1179 
1180 		com->multiport = TRUE;
1181 		kprintf(" (multiport");
1182 		if (unit == COM_MPMASTER(flags))
1183 			kprintf(" master");
1184 		kprintf(")");
1185 		masterdev = devclass_get_device(sio_devclass,
1186 		    COM_MPMASTER(flags));
1187 		com->no_irq = (masterdev == NULL || bus_get_resource(masterdev,
1188 		    SYS_RES_IRQ, 0, NULL, NULL) != 0);
1189 	 }
1190 #endif /* COM_MULTIPORT */
1191 	if (unit == comconsole)
1192 		kprintf(", console");
1193 	if (COM_IIR_TXRDYBUG(flags))
1194 		kprintf(" with a bogus IIR_TXRDY register");
1195 	kprintf("\n");
1196 
1197 	if (!sio_registered) {
1198 		register_swi(SWI_TTY, siopoll, NULL ,"swi_siopoll", NULL);
1199 		sio_registered = TRUE;
1200 	}
1201 	minorbase = UNIT_TO_MINOR(unit);
1202 	make_dev(&sio_ops, minorbase,
1203 	    UID_ROOT, GID_WHEEL, 0600, "ttyd%r", unit);
1204 	make_dev(&sio_ops, minorbase | CONTROL_INIT_STATE,
1205 	    UID_ROOT, GID_WHEEL, 0600, "ttyid%r", unit);
1206 	make_dev(&sio_ops, minorbase | CONTROL_LOCK_STATE,
1207 	    UID_ROOT, GID_WHEEL, 0600, "ttyld%r", unit);
1208 	make_dev(&sio_ops, minorbase | CALLOUT_MASK,
1209 	    UID_UUCP, GID_DIALER, 0660, "cuaa%r", unit);
1210 	make_dev(&sio_ops, minorbase | CALLOUT_MASK | CONTROL_INIT_STATE,
1211 	    UID_UUCP, GID_DIALER, 0660, "cuaia%r", unit);
1212 	make_dev(&sio_ops, minorbase | CALLOUT_MASK | CONTROL_LOCK_STATE,
1213 	    UID_UUCP, GID_DIALER, 0660, "cuala%r", unit);
1214 	com->flags = flags;
1215 	com->pps.ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR;
1216 	pps_init(&com->pps);
1217 
1218 	rid = 0;
1219 	com->irqres = bus_alloc_resource(dev, SYS_RES_IRQ, &rid, 0ul, ~0ul, 1,
1220 	    RF_ACTIVE);
1221 	if (com->irqres) {
1222 		ret = BUS_SETUP_INTR(device_get_parent(dev), dev,
1223 				     com->irqres, INTR_MPSAFE, siointr, com,
1224 				     &com->cookie, NULL);
1225 		if (ret)
1226 			device_printf(dev, "could not activate interrupt\n");
1227 #if defined(DDB) && (defined(BREAK_TO_DEBUGGER) || \
1228     defined(ALT_BREAK_TO_DEBUGGER))
1229 		/*
1230 		 * Enable interrupts for early break-to-debugger support
1231 		 * on the console.
1232 		 */
1233 		if (ret == 0 && unit == comconsole)
1234 			outb(siocniobase + com_ier, IER_ERXRDY | IER_ERLS |
1235 			    IER_EMSC);
1236 #endif
1237 	}
1238 
1239 	lwkt_reltoken(&tty_token);
1240 	return (0);
1241 }
1242 
1243 static int
1244 sioopen(struct dev_open_args *ap)
1245 {
1246 	cdev_t dev = ap->a_head.a_dev;
1247 	struct com_s	*com;
1248 	int		error;
1249 	int		mynor;
1250 	struct tty	*tp;
1251 	int		unit;
1252 
1253 	mynor = minor(dev);
1254 	unit = MINOR_TO_UNIT(mynor);
1255 	com = com_addr(unit);
1256 	if (com == NULL)
1257 		return (ENXIO);
1258 	if (com->gone)
1259 		return (ENXIO);
1260 	if (mynor & CONTROL_MASK)
1261 		return (0);
1262 	lwkt_gettoken(&tty_token);
1263 	tp = dev->si_tty = com->tp = ttymalloc(com->tp);
1264 	crit_enter();
1265 	/*
1266 	 * We jump to this label after all non-interrupted sleeps to pick
1267 	 * up any changes of the device state.
1268 	 */
1269 open_top:
1270 	while (com->state & CS_DTR_OFF) {
1271 		error = tsleep(&com->dtr_wait, PCATCH, "siodtr", 0);
1272 		if (com_addr(unit) == NULL) {
1273 			crit_exit();
1274 			lwkt_reltoken(&tty_token);
1275 			return (ENXIO);
1276 		}
1277 		if (error != 0 || com->gone)
1278 			goto out;
1279 	}
1280 	if (tp->t_state & TS_ISOPEN) {
1281 		/*
1282 		 * The device is open, so everything has been initialized.
1283 		 * Handle conflicts.
1284 		 */
1285 		if (mynor & CALLOUT_MASK) {
1286 			if (!com->active_out) {
1287 				error = EBUSY;
1288 				goto out;
1289 			}
1290 		} else {
1291 			if (com->active_out) {
1292 				if (ap->a_oflags & O_NONBLOCK) {
1293 					error = EBUSY;
1294 					goto out;
1295 				}
1296 				error =	tsleep(&com->active_out,
1297 					       PCATCH, "siobi", 0);
1298 				if (com_addr(unit) == NULL) {
1299 					crit_exit();
1300 					lwkt_reltoken(&tty_token);
1301 					return (ENXIO);
1302 				}
1303 				if (error != 0 || com->gone)
1304 					goto out;
1305 				goto open_top;
1306 			}
1307 		}
1308 		if (tp->t_state & TS_XCLUDE && priv_check_cred(ap->a_cred, PRIV_ROOT, 0)) {
1309 			error = EBUSY;
1310 			goto out;
1311 		}
1312 	} else {
1313 		/*
1314 		 * The device isn't open, so there are no conflicts.
1315 		 * Initialize it.  Initialization is done twice in many
1316 		 * cases: to preempt sleeping callin opens if we are
1317 		 * callout, and to complete a callin open after DCD rises.
1318 		 */
1319 		tp->t_oproc = comstart;
1320 		tp->t_param = comparam;
1321 		tp->t_stop = comstop;
1322 		tp->t_dev = dev;
1323 		tp->t_termios = mynor & CALLOUT_MASK
1324 				? com->it_out : com->it_in;
1325 		(void)commctl(com, TIOCM_DTR | TIOCM_RTS, DMSET);
1326 		com->poll = com->no_irq;
1327 		com->poll_output = com->loses_outints;
1328 		++com->wopeners;
1329 		error = comparam(tp, &tp->t_termios);
1330 		--com->wopeners;
1331 		if (error != 0)
1332 			goto out;
1333 		/*
1334 		 * XXX we should goto open_top if comparam() slept.
1335 		 */
1336 		if (com->hasfifo) {
1337 			/*
1338 			 * (Re)enable and drain fifos.
1339 			 *
1340 			 * Certain SMC chips cause problems if the fifos
1341 			 * are enabled while input is ready.  Turn off the
1342 			 * fifo if necessary to clear the input.  We test
1343 			 * the input ready bit after enabling the fifos
1344 			 * since we've already enabled them in comparam()
1345 			 * and to handle races between enabling and fresh
1346 			 * input.
1347 			 */
1348 			while (TRUE) {
1349 				sio_setreg(com, com_fifo,
1350 					   FIFO_RCV_RST | FIFO_XMT_RST
1351 					   | com->fifo_image);
1352 				/*
1353 				 * XXX the delays are for superstitious
1354 				 * historical reasons.  It must be less than
1355 				 * the character time at the maximum
1356 				 * supported speed (87 usec at 115200 bps
1357 				 * 8N1).  Otherwise we might loop endlessly
1358 				 * if data is streaming in.  We used to use
1359 				 * delays of 100.  That usually worked
1360 				 * because DELAY(100) used to usually delay
1361 				 * for about 85 usec instead of 100.
1362 				 */
1363 				DELAY(50);
1364 				if (!(inb(com->line_status_port) & LSR_RXRDY))
1365 					break;
1366 				sio_setreg(com, com_fifo, 0);
1367 				DELAY(50);
1368 				(void) inb(com->data_port);
1369 			}
1370 		}
1371 
1372 		com_lock();
1373 		(void) inb(com->line_status_port);
1374 		(void) inb(com->data_port);
1375 		com->prev_modem_status = com->last_modem_status
1376 		    = inb(com->modem_status_port);
1377 		if (COM_IIR_TXRDYBUG(com->flags)) {
1378 			outb(com->intr_ctl_port, IER_ERXRDY | IER_ERLS
1379 						| IER_EMSC);
1380 		} else {
1381 			outb(com->intr_ctl_port, IER_ERXRDY | IER_ETXRDY
1382 						| IER_ERLS | IER_EMSC);
1383 		}
1384 		com_unlock();
1385 		/*
1386 		 * Handle initial DCD.  Callout devices get a fake initial
1387 		 * DCD (trapdoor DCD).  If we are callout, then any sleeping
1388 		 * callin opens get woken up and resume sleeping on "siobi"
1389 		 * instead of "siodcd".
1390 		 */
1391 		/*
1392 		 * XXX `mynor & CALLOUT_MASK' should be
1393 		 * `tp->t_cflag & (SOFT_CARRIER | TRAPDOOR_CARRIER) where
1394 		 * TRAPDOOR_CARRIER is the default initial state for callout
1395 		 * devices and SOFT_CARRIER is like CLOCAL except it hides
1396 		 * the true carrier.
1397 		 */
1398 		if (com->prev_modem_status & MSR_DCD || mynor & CALLOUT_MASK)
1399 			(*linesw[tp->t_line].l_modem)(tp, 1);
1400 	}
1401 	/*
1402 	 * Wait for DCD if necessary.
1403 	 */
1404 	if (!(tp->t_state & TS_CARR_ON) && !(mynor & CALLOUT_MASK)
1405 	    && !(tp->t_cflag & CLOCAL) && !(ap->a_oflags & O_NONBLOCK)) {
1406 		++com->wopeners;
1407 		error = tsleep(TSA_CARR_ON(tp), PCATCH, "siodcd", 0);
1408 		if (com_addr(unit) == NULL) {
1409 			crit_exit();
1410 			lwkt_reltoken(&tty_token);
1411 			return (ENXIO);
1412 		}
1413 		--com->wopeners;
1414 		if (error != 0 || com->gone)
1415 			goto out;
1416 		goto open_top;
1417 	}
1418 	error =	(*linesw[tp->t_line].l_open)(dev, tp);
1419 	disc_optim(tp, &tp->t_termios, com);
1420 	if (tp->t_state & TS_ISOPEN && mynor & CALLOUT_MASK)
1421 		com->active_out = TRUE;
1422 	siosettimeout();
1423 out:
1424 	crit_exit();
1425 	if (!(tp->t_state & TS_ISOPEN) && com->wopeners == 0)
1426 		comhardclose(com);
1427 	lwkt_reltoken(&tty_token);
1428 	return (error);
1429 }
1430 
1431 static int
1432 sioclose(struct dev_close_args *ap)
1433 {
1434 	cdev_t dev = ap->a_head.a_dev;
1435 	struct com_s	*com;
1436 	int		mynor;
1437 	struct tty	*tp;
1438 
1439 	mynor = minor(dev);
1440 	if (mynor & CONTROL_MASK)
1441 		return (0);
1442 	lwkt_gettoken(&tty_token);
1443 	com = com_addr(MINOR_TO_UNIT(mynor));
1444 	if (com == NULL) {
1445 		lwkt_reltoken(&tty_token);
1446 		return (ENODEV);
1447 	}
1448 	tp = com->tp;
1449 	crit_enter();
1450 	(*linesw[tp->t_line].l_close)(tp, ap->a_fflag);
1451 	disc_optim(tp, &tp->t_termios, com);
1452 	comstop(tp, FREAD | FWRITE);
1453 	comhardclose(com);
1454 	ttyclose(tp);
1455 	siosettimeout();
1456 	crit_exit();
1457 	if (com->gone) {
1458 		kprintf("sio%d: gone\n", com->unit);
1459 		crit_enter();
1460 		if (com->ibuf != NULL)
1461 			kfree(com->ibuf, M_DEVBUF);
1462 		bzero(tp, sizeof *tp);
1463 		crit_exit();
1464 	}
1465 	lwkt_reltoken(&tty_token);
1466 	return (0);
1467 }
1468 
1469 static void
1470 comhardclose(struct com_s *com)
1471 {
1472 	struct tty	*tp;
1473 	int		unit;
1474 
1475 	unit = com->unit;
1476 	crit_enter();
1477 	lwkt_gettoken(&tty_token);
1478 	com->poll = FALSE;
1479 	com->poll_output = FALSE;
1480 	com->do_timestamp = FALSE;
1481 	com->do_dcd_timestamp = FALSE;
1482 	com->pps.ppsparam.mode = 0;
1483 	sio_setreg(com, com_cfcr, com->cfcr_image &= ~CFCR_SBREAK);
1484 	tp = com->tp;
1485 
1486 #if defined(DDB) && (defined(BREAK_TO_DEBUGGER) || \
1487     defined(ALT_BREAK_TO_DEBUGGER))
1488 	/*
1489 	 * Leave interrupts enabled and don't clear DTR if this is the
1490 	 * console. This allows us to detect break-to-debugger events
1491 	 * while the console device is closed.
1492 	 */
1493 	if (com->unit != comconsole)
1494 #endif
1495 	{
1496 		sio_setreg(com, com_ier, 0);
1497 		if (tp->t_cflag & HUPCL
1498 		    /*
1499 		     * XXX we will miss any carrier drop between here and the
1500 		     * next open.  Perhaps we should watch DCD even when the
1501 		     * port is closed; it is not sufficient to check it at
1502 		     * the next open because it might go up and down while
1503 		     * we're not watching.
1504 		     */
1505 		    || (!com->active_out
1506 		        && !(com->prev_modem_status & MSR_DCD)
1507 		        && !(com->it_in.c_cflag & CLOCAL))
1508 		    || !(tp->t_state & TS_ISOPEN)) {
1509 			(void)commctl(com, TIOCM_DTR, DMBIC);
1510 			if (com->dtr_wait != 0 && !(com->state & CS_DTR_OFF)) {
1511 				callout_reset(&com->dtr_ch, com->dtr_wait,
1512 						siodtrwakeup, com);
1513 				com->state |= CS_DTR_OFF;
1514 			}
1515 		}
1516 	}
1517 	if (com->hasfifo) {
1518 		/*
1519 		 * Disable fifos so that they are off after controlled
1520 		 * reboots.  Some BIOSes fail to detect 16550s when the
1521 		 * fifos are enabled.
1522 		 */
1523 		sio_setreg(com, com_fifo, 0);
1524 	}
1525 	com->active_out = FALSE;
1526 	wakeup(&com->active_out);
1527 	wakeup(TSA_CARR_ON(tp));	/* restart any wopeners */
1528 	lwkt_reltoken(&tty_token);
1529 	crit_exit();
1530 }
1531 
1532 static int
1533 sioread(struct dev_read_args *ap)
1534 {
1535 	cdev_t dev = ap->a_head.a_dev;
1536 	int		mynor, ret;
1537 	struct com_s	*com;
1538 
1539 	lwkt_gettoken(&tty_token);
1540 	mynor = minor(dev);
1541 	if (mynor & CONTROL_MASK) {
1542 		lwkt_reltoken(&tty_token);
1543 		return (ENODEV);
1544 	}
1545 	com = com_addr(MINOR_TO_UNIT(mynor));
1546 	if (com == NULL || com->gone) {
1547 		lwkt_reltoken(&tty_token);
1548 		return (ENODEV);
1549 	}
1550 	ret = ((*linesw[com->tp->t_line].l_read)(com->tp, ap->a_uio, ap->a_ioflag));
1551 	lwkt_reltoken(&tty_token);
1552 	return ret;
1553 }
1554 
1555 static int
1556 siowrite(struct dev_write_args *ap)
1557 {
1558 	cdev_t dev = ap->a_head.a_dev;
1559 	int		mynor;
1560 	struct com_s	*com;
1561 	int		unit, ret;
1562 
1563 	lwkt_gettoken(&tty_token);
1564 	mynor = minor(dev);
1565 	if (mynor & CONTROL_MASK) {
1566 		lwkt_reltoken(&tty_token);
1567 		return (ENODEV);
1568 	}
1569 
1570 	unit = MINOR_TO_UNIT(mynor);
1571 	com = com_addr(unit);
1572 	if (com == NULL || com->gone) {
1573 		lwkt_reltoken(&tty_token);
1574 		return (ENODEV);
1575 	}
1576 	/*
1577 	 * (XXX) We disallow virtual consoles if the physical console is
1578 	 * a serial port.  This is in case there is a display attached that
1579 	 * is not the console.  In that situation we don't need/want the X
1580 	 * server taking over the console.
1581 	 */
1582 	if (constty != NULL && unit == comconsole)
1583 		constty = NULL;
1584 	ret = ((*linesw[com->tp->t_line].l_write)(com->tp, ap->a_uio, ap->a_ioflag));
1585 	lwkt_reltoken(&tty_token);
1586 	return ret;
1587 }
1588 
1589 static void
1590 siobusycheck(void *chan)
1591 {
1592 	struct com_s	*com;
1593 
1594 	lwkt_gettoken(&tty_token);
1595 	com = (struct com_s *)chan;
1596 
1597 	/*
1598 	 * Clear TS_BUSY if low-level output is complete.
1599 	 * spl locking is sufficient because siointr1() does not set CS_BUSY.
1600 	 * If siointr1() clears CS_BUSY after we look at it, then we'll get
1601 	 * called again.  Reading the line status port outside of siointr1()
1602 	 * is safe because CS_BUSY is clear so there are no output interrupts
1603 	 * to lose.
1604 	 */
1605 	crit_enter();
1606 	if (com->state & CS_BUSY)
1607 		com->extra_state &= ~CSE_BUSYCHECK;	/* False alarm. */
1608 	else if ((inb(com->line_status_port) & (LSR_TSRE | LSR_TXRDY))
1609 	    == (LSR_TSRE | LSR_TXRDY)) {
1610 		com->tp->t_state &= ~TS_BUSY;
1611 		ttwwakeup(com->tp);
1612 		com->extra_state &= ~CSE_BUSYCHECK;
1613 	} else {
1614 		callout_reset(&com->busy_ch, hz / 100, siobusycheck, com);
1615 	}
1616 	crit_exit();
1617 	lwkt_reltoken(&tty_token);
1618 }
1619 
1620 static u_int
1621 siodivisor(u_long rclk, speed_t speed)
1622 {
1623 	long	actual_speed;
1624 	u_int	divisor;
1625 	int	error;
1626 
1627 	if (speed == 0 || speed > ((speed_t)-1 - 1) / 8)
1628 		return (0);
1629 	divisor = (rclk / (8UL * speed) + 1) / 2;
1630 	if (divisor == 0 || divisor >= 65536)
1631 		return (0);
1632 	actual_speed = rclk / (16UL * divisor);
1633 
1634 	/* 10 times error in percent: */
1635 	error = ((actual_speed - (long)speed) * 2000 / (long)speed + 1) / 2;
1636 
1637 	/* 3.0% maximum error tolerance: */
1638 	if (error < -30 || error > 30)
1639 		return (0);
1640 
1641 	return (divisor);
1642 }
1643 
1644 static void
1645 siodtrwakeup(void *chan)
1646 {
1647 	struct com_s	*com;
1648 
1649 	lwkt_gettoken(&tty_token);
1650 	com = (struct com_s *)chan;
1651 	com->state &= ~CS_DTR_OFF;
1652 	wakeup(&com->dtr_wait);
1653 	lwkt_reltoken(&tty_token);
1654 }
1655 
1656 /*
1657  * NOTE: Normally called with tty_token held but might not be when
1658  *	 operating as the console.
1659  *
1660  *	 Must be called with com_lock
1661  */
1662 static void
1663 sioinput(struct com_s *com)
1664 {
1665 	u_char		*buf;
1666 	int		incc;
1667 	u_char		line_status;
1668 	int		recv_data;
1669 	struct tty	*tp;
1670 
1671 	buf = com->ibuf;
1672 	tp = com->tp;
1673 	if (!(tp->t_state & TS_ISOPEN) || !(tp->t_cflag & CREAD)) {
1674 		com_events -= (com->iptr - com->ibuf);
1675 		com->iptr = com->ibuf;
1676 		return;
1677 	}
1678 	if (tp->t_state & TS_CAN_BYPASS_L_RINT) {
1679 		/*
1680 		 * Avoid the grotesquely inefficient lineswitch routine
1681 		 * (ttyinput) in "raw" mode.  It usually takes about 450
1682 		 * instructions (that's without canonical processing or echo!).
1683 		 * slinput is reasonably fast (usually 40 instructions plus
1684 		 * call overhead).
1685 		 */
1686 		do {
1687 			com_unlock();
1688 			incc = com->iptr - buf;
1689 			if (tp->t_rawq.c_cc + incc > tp->t_ihiwat
1690 			    && (com->state & CS_RTS_IFLOW
1691 				|| tp->t_iflag & IXOFF)
1692 			    && !(tp->t_state & TS_TBLOCK))
1693 				ttyblock(tp);
1694 			com->delta_error_counts[CE_TTY_BUF_OVERFLOW]
1695 				+= b_to_q((char *)buf, incc, &tp->t_rawq);
1696 			buf += incc;
1697 			tk_nin += incc;
1698 			tk_rawcc += incc;
1699 			tp->t_rawcc += incc;
1700 			ttwakeup(tp);
1701 			if (tp->t_state & TS_TTSTOP
1702 			    && (tp->t_iflag & IXANY
1703 				|| tp->t_cc[VSTART] == tp->t_cc[VSTOP])) {
1704 				tp->t_state &= ~TS_TTSTOP;
1705 				tp->t_lflag &= ~FLUSHO;
1706 				comstart(tp);
1707 			}
1708 			com_lock();
1709 		} while (buf < com->iptr);
1710 	} else {
1711 		do {
1712 			com_unlock();
1713 			line_status = buf[com->ierroff];
1714 			recv_data = *buf++;
1715 			if (line_status
1716 			    & (LSR_BI | LSR_FE | LSR_OE | LSR_PE)) {
1717 				if (line_status & LSR_BI)
1718 					recv_data |= TTY_BI;
1719 				if (line_status & LSR_FE)
1720 					recv_data |= TTY_FE;
1721 				if (line_status & LSR_OE)
1722 					recv_data |= TTY_OE;
1723 				if (line_status & LSR_PE)
1724 					recv_data |= TTY_PE;
1725 			}
1726 			(*linesw[tp->t_line].l_rint)(recv_data, tp);
1727 			com_lock();
1728 		} while (buf < com->iptr);
1729 	}
1730 	com_events -= (com->iptr - com->ibuf);
1731 	com->iptr = com->ibuf;
1732 
1733 	/*
1734 	 * There is now room for another low-level buffer full of input,
1735 	 * so enable RTS if it is now disabled and there is room in the
1736 	 * high-level buffer.
1737 	 */
1738 	if ((com->state & CS_RTS_IFLOW) && !(com->mcr_image & MCR_RTS) &&
1739 	    !(tp->t_state & TS_TBLOCK))
1740 		outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
1741 }
1742 
1743 void
1744 siointr(void *arg)
1745 {
1746 	lwkt_gettoken(&tty_token);
1747 #ifndef COM_MULTIPORT
1748 	com_lock();
1749 	siointr1((struct com_s *) arg);
1750 	com_unlock();
1751 #else /* COM_MULTIPORT */
1752 	bool_t		possibly_more_intrs;
1753 	int		unit;
1754 	struct com_s	*com;
1755 
1756 	/*
1757 	 * Loop until there is no activity on any port.  This is necessary
1758 	 * to get an interrupt edge more than to avoid another interrupt.
1759 	 * If the IRQ signal is just an OR of the IRQ signals from several
1760 	 * devices, then the edge from one may be lost because another is
1761 	 * on.
1762 	 */
1763 	com_lock();
1764 	do {
1765 		possibly_more_intrs = FALSE;
1766 		for (unit = 0; unit < sio_numunits; ++unit) {
1767 			com = com_addr(unit);
1768 			/*
1769 			 * XXX com_lock();
1770 			 * would it work here, or be counter-productive?
1771 			 */
1772 			if (com != NULL
1773 			    && !com->gone
1774 			    && (inb(com->int_id_port) & IIR_IMASK)
1775 			       != IIR_NOPEND) {
1776 				siointr1(com);
1777 				possibly_more_intrs = TRUE;
1778 			}
1779 			/* XXX com_unlock(); */
1780 		}
1781 	} while (possibly_more_intrs);
1782 	com_unlock();
1783 #endif /* COM_MULTIPORT */
1784 	lwkt_reltoken(&tty_token);
1785 }
1786 
1787 /*
1788  * Called with tty_token held and com_lock held.
1789  */
1790 static void
1791 siointr1(struct com_s *com)
1792 {
1793 	u_char	line_status;
1794 	u_char	modem_status;
1795 	u_char	*ioptr;
1796 	u_char	recv_data;
1797 	u_char	int_ctl;
1798 	u_char	int_ctl_new;
1799 	u_int	count;
1800 
1801 	int_ctl = inb(com->intr_ctl_port);
1802 	int_ctl_new = int_ctl;
1803 
1804 	while (!com->gone) {
1805 		if (com->pps.ppsparam.mode & PPS_CAPTUREBOTH) {
1806 			modem_status = inb(com->modem_status_port);
1807 		        if ((modem_status ^ com->last_modem_status) & MSR_DCD) {
1808 				count = sys_cputimer->count();
1809 				pps_event(&com->pps, count,
1810 				    (modem_status & MSR_DCD) ?
1811 				    PPS_CAPTUREASSERT : PPS_CAPTURECLEAR);
1812 			}
1813 		}
1814 		line_status = inb(com->line_status_port);
1815 
1816 		/* input event? (check first to help avoid overruns) */
1817 		while (line_status & LSR_RCV_MASK) {
1818 			/* break/unnattached error bits or real input? */
1819 			if (!(line_status & LSR_RXRDY))
1820 				recv_data = 0;
1821 			else
1822 				recv_data = inb(com->data_port);
1823 #if defined(DDB) && defined(ALT_BREAK_TO_DEBUGGER)
1824 			/*
1825 			 * Solaris implements a new BREAK which is initiated
1826 			 * by a character sequence CR ~ ^b which is similar
1827 			 * to a familiar pattern used on Sun servers by the
1828 			 * Remote Console.
1829 			 */
1830 #define	KEY_CRTLB	2	/* ^B */
1831 #define	KEY_CR		13	/* CR '\r' */
1832 #define	KEY_TILDE	126	/* ~ */
1833 
1834 			if (com->unit == comconsole) {
1835 				static int brk_state1 = 0, brk_state2 = 0;
1836 				if (recv_data == KEY_CR) {
1837 					brk_state1 = recv_data;
1838 					brk_state2 = 0;
1839 				} else if (brk_state1 == KEY_CR && (recv_data == KEY_TILDE || recv_data == KEY_CRTLB)) {
1840 					if (recv_data == KEY_TILDE)
1841 						brk_state2 = recv_data;
1842 					else if (brk_state2 == KEY_TILDE && recv_data == KEY_CRTLB) {
1843 							com_unlock();
1844 							breakpoint();
1845 							com_lock();
1846 							brk_state1 = brk_state2 = 0;
1847 							goto cont;
1848 					} else
1849 						brk_state2 = 0;
1850 				} else
1851 					brk_state1 = 0;
1852 			}
1853 #endif
1854 			if (line_status & (LSR_BI | LSR_FE | LSR_PE)) {
1855 				/*
1856 				 * Don't store BI if IGNBRK or FE/PE if IGNPAR.
1857 				 * Otherwise, push the work to a higher level
1858 				 * (to handle PARMRK) if we're bypassing.
1859 				 * Otherwise, convert BI/FE and PE+INPCK to 0.
1860 				 *
1861 				 * This makes bypassing work right in the
1862 				 * usual "raw" case (IGNBRK set, and IGNPAR
1863 				 * and INPCK clear).
1864 				 *
1865 				 * Note: BI together with FE/PE means just BI.
1866 				 */
1867 				if (line_status & LSR_BI) {
1868 #if defined(DDB) && defined(BREAK_TO_DEBUGGER)
1869 					if (com->unit == comconsole) {
1870 						com_unlock();
1871 						breakpoint();
1872 						com_lock();
1873 						goto cont;
1874 					}
1875 #endif
1876 					if (com->tp == NULL
1877 					    || com->tp->t_iflag & IGNBRK)
1878 						goto cont;
1879 				} else {
1880 					if (com->tp == NULL
1881 					    || com->tp->t_iflag & IGNPAR)
1882 						goto cont;
1883 				}
1884 				if (com->tp->t_state & TS_CAN_BYPASS_L_RINT
1885 				    && (line_status & (LSR_BI | LSR_FE)
1886 					|| com->tp->t_iflag & INPCK))
1887 					recv_data = 0;
1888 			}
1889 			++com->bytes_in;
1890 			if (com->hotchar != 0 && recv_data == com->hotchar)
1891 				setsofttty();
1892 			ioptr = com->iptr;
1893 			if (ioptr >= com->ibufend)
1894 				CE_RECORD(com, CE_INTERRUPT_BUF_OVERFLOW);
1895 			else {
1896 				if (com->do_timestamp)
1897 					microtime(&com->timestamp);
1898 				++com_events;
1899 				schedsofttty();
1900 #if 0 /* for testing input latency vs efficiency */
1901 if (com->iptr - com->ibuf == 8)
1902 	setsofttty();
1903 #endif
1904 				ioptr[0] = recv_data;
1905 				ioptr[com->ierroff] = line_status;
1906 				com->iptr = ++ioptr;
1907 				if (ioptr == com->ihighwater
1908 				    && com->state & CS_RTS_IFLOW)
1909 					outb(com->modem_ctl_port,
1910 					     com->mcr_image &= ~MCR_RTS);
1911 				if (line_status & LSR_OE)
1912 					CE_RECORD(com, CE_OVERRUN);
1913 			}
1914 cont:
1915 			/*
1916 			 * "& 0x7F" is to avoid the gcc-1.40 generating a slow
1917 			 * jump from the top of the loop to here
1918 			 */
1919 			line_status = inb(com->line_status_port) & 0x7F;
1920 		}
1921 
1922 		/* modem status change? (always check before doing output) */
1923 		modem_status = inb(com->modem_status_port);
1924 		if (modem_status != com->last_modem_status) {
1925 			if (com->do_dcd_timestamp
1926 			    && !(com->last_modem_status & MSR_DCD)
1927 			    && modem_status & MSR_DCD)
1928 				microtime(&com->dcd_timestamp);
1929 
1930 			/*
1931 			 * Schedule high level to handle DCD changes.  Note
1932 			 * that we don't use the delta bits anywhere.  Some
1933 			 * UARTs mess them up, and it's easy to remember the
1934 			 * previous bits and calculate the delta.
1935 			 */
1936 			com->last_modem_status = modem_status;
1937 			if (!(com->state & CS_CHECKMSR)) {
1938 				com_events += LOTS_OF_EVENTS;
1939 				com->state |= CS_CHECKMSR;
1940 				setsofttty();
1941 			}
1942 
1943 			/* handle CTS change immediately for crisp flow ctl */
1944 			if (com->state & CS_CTS_OFLOW) {
1945 				if (modem_status & MSR_CTS)
1946 					com->state |= CS_ODEVREADY;
1947 				else
1948 					com->state &= ~CS_ODEVREADY;
1949 			}
1950 		}
1951 
1952 		/* output queued and everything ready? */
1953 		if (line_status & LSR_TXRDY
1954 		    && com->state >= (CS_BUSY | CS_TTGO | CS_ODEVREADY)) {
1955 			ioptr = com->obufq.l_head;
1956 			if (com->tx_fifo_size > 1) {
1957 				u_int	ocount;
1958 
1959 				ocount = com->obufq.l_tail - ioptr;
1960 				if (ocount > com->tx_fifo_size)
1961 					ocount = com->tx_fifo_size;
1962 				com->bytes_out += ocount;
1963 				do
1964 					outb(com->data_port, *ioptr++);
1965 				while (--ocount != 0);
1966 			} else {
1967 				outb(com->data_port, *ioptr++);
1968 				++com->bytes_out;
1969 			}
1970 			com->obufq.l_head = ioptr;
1971 			if (COM_IIR_TXRDYBUG(com->flags)) {
1972 				int_ctl_new = int_ctl | IER_ETXRDY;
1973 			}
1974 			if (ioptr >= com->obufq.l_tail) {
1975 				struct lbq	*qp;
1976 
1977 				qp = com->obufq.l_next;
1978 				qp->l_queued = FALSE;
1979 				qp = qp->l_next;
1980 				if (qp != NULL) {
1981 					com->obufq.l_head = qp->l_head;
1982 					com->obufq.l_tail = qp->l_tail;
1983 					com->obufq.l_next = qp;
1984 				} else {
1985 					/* output just completed */
1986 					if (COM_IIR_TXRDYBUG(com->flags)) {
1987 						int_ctl_new = int_ctl & ~IER_ETXRDY;
1988 					}
1989 					com->state &= ~CS_BUSY;
1990 				}
1991 				if (!(com->state & CS_ODONE)) {
1992 					com_events += LOTS_OF_EVENTS;
1993 					com->state |= CS_ODONE;
1994 					setsofttty();	/* handle at high level ASAP */
1995 				}
1996 			}
1997 			if (COM_IIR_TXRDYBUG(com->flags) && (int_ctl != int_ctl_new)) {
1998 				outb(com->intr_ctl_port, int_ctl_new);
1999 			}
2000 		}
2001 
2002 		/* finished? */
2003 #ifndef COM_MULTIPORT
2004 		if ((inb(com->int_id_port) & IIR_IMASK) == IIR_NOPEND)
2005 #endif /* COM_MULTIPORT */
2006 		{
2007 			return;
2008 		}
2009 	}
2010 }
2011 
2012 static int
2013 sioioctl(struct dev_ioctl_args *ap)
2014 {
2015 	cdev_t dev = ap->a_head.a_dev;
2016 	caddr_t data = ap->a_data;
2017 	struct com_s	*com;
2018 	int		error;
2019 	int		mynor;
2020 	struct tty	*tp;
2021 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
2022 	u_long		oldcmd;
2023 	struct termios	term;
2024 #endif
2025 	lwkt_gettoken(&tty_token);
2026 	mynor = minor(dev);
2027 
2028 	com = com_addr(MINOR_TO_UNIT(mynor));
2029 	if (com == NULL || com->gone) {
2030 		lwkt_reltoken(&tty_token);
2031 		return (ENODEV);
2032 	}
2033 	if (mynor & CONTROL_MASK) {
2034 		struct termios	*ct;
2035 
2036 		switch (mynor & CONTROL_MASK) {
2037 		case CONTROL_INIT_STATE:
2038 			ct = mynor & CALLOUT_MASK ? &com->it_out : &com->it_in;
2039 			break;
2040 		case CONTROL_LOCK_STATE:
2041 			ct = mynor & CALLOUT_MASK ? &com->lt_out : &com->lt_in;
2042 			break;
2043 		default:
2044 			lwkt_reltoken(&tty_token);
2045 			return (ENODEV);	/* /dev/nodev */
2046 		}
2047 		switch (ap->a_cmd) {
2048 		case TIOCSETA:
2049 			error = priv_check_cred(ap->a_cred, PRIV_ROOT, 0);
2050 			if (error != 0)
2051 				return (error);
2052 			*ct = *(struct termios *)data;
2053 			lwkt_reltoken(&tty_token);
2054 			return (0);
2055 		case TIOCGETA:
2056 			*(struct termios *)data = *ct;
2057 			lwkt_reltoken(&tty_token);
2058 			return (0);
2059 		case TIOCGETD:
2060 			*(int *)data = TTYDISC;
2061 			lwkt_reltoken(&tty_token);
2062 			return (0);
2063 		case TIOCGWINSZ:
2064 			bzero(data, sizeof(struct winsize));
2065 			lwkt_reltoken(&tty_token);
2066 			return (0);
2067 		default:
2068 			lwkt_reltoken(&tty_token);
2069 			return (ENOTTY);
2070 		}
2071 	}
2072 	tp = com->tp;
2073 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
2074 	term = tp->t_termios;
2075 	oldcmd = ap->a_cmd;
2076 	error = ttsetcompat(tp, &ap->a_cmd, data, &term);
2077 	if (error != 0) {
2078 		lwkt_reltoken(&tty_token);
2079 		return (error);
2080 	}
2081 	if (ap->a_cmd != oldcmd)
2082 		data = (caddr_t)&term;
2083 #endif
2084 	if (ap->a_cmd == TIOCSETA || ap->a_cmd == TIOCSETAW ||
2085 	    ap->a_cmd == TIOCSETAF) {
2086 		int	cc;
2087 		struct termios *dt = (struct termios *)data;
2088 		struct termios *lt = mynor & CALLOUT_MASK
2089 				     ? &com->lt_out : &com->lt_in;
2090 
2091 		dt->c_iflag = (tp->t_iflag & lt->c_iflag)
2092 			      | (dt->c_iflag & ~lt->c_iflag);
2093 		dt->c_oflag = (tp->t_oflag & lt->c_oflag)
2094 			      | (dt->c_oflag & ~lt->c_oflag);
2095 		dt->c_cflag = (tp->t_cflag & lt->c_cflag)
2096 			      | (dt->c_cflag & ~lt->c_cflag);
2097 		dt->c_lflag = (tp->t_lflag & lt->c_lflag)
2098 			      | (dt->c_lflag & ~lt->c_lflag);
2099 		for (cc = 0; cc < NCCS; ++cc)
2100 			if (lt->c_cc[cc] != 0)
2101 				dt->c_cc[cc] = tp->t_cc[cc];
2102 		if (lt->c_ispeed != 0)
2103 			dt->c_ispeed = tp->t_ispeed;
2104 		if (lt->c_ospeed != 0)
2105 			dt->c_ospeed = tp->t_ospeed;
2106 	}
2107 	error = (*linesw[tp->t_line].l_ioctl)(tp, ap->a_cmd, data, ap->a_fflag, ap->a_cred);
2108 	if (error != ENOIOCTL) {
2109 		lwkt_reltoken(&tty_token);
2110 		return (error);
2111 	}
2112 	crit_enter();
2113 	error = ttioctl(tp, ap->a_cmd, data, ap->a_fflag);
2114 	disc_optim(tp, &tp->t_termios, com);
2115 	if (error != ENOIOCTL) {
2116 		crit_exit();
2117 		lwkt_reltoken(&tty_token);
2118 		return (error);
2119 	}
2120 	switch (ap->a_cmd) {
2121 	case TIOCSBRK:
2122 		sio_setreg(com, com_cfcr, com->cfcr_image |= CFCR_SBREAK);
2123 		break;
2124 	case TIOCCBRK:
2125 		sio_setreg(com, com_cfcr, com->cfcr_image &= ~CFCR_SBREAK);
2126 		break;
2127 	case TIOCSDTR:
2128 		(void)commctl(com, TIOCM_DTR, DMBIS);
2129 		break;
2130 	case TIOCCDTR:
2131 		(void)commctl(com, TIOCM_DTR, DMBIC);
2132 		break;
2133 	/*
2134 	 * XXX should disallow changing MCR_RTS if CS_RTS_IFLOW is set.  The
2135 	 * changes get undone on the next call to comparam().
2136 	 */
2137 	case TIOCMSET:
2138 		(void)commctl(com, *(int *)data, DMSET);
2139 		break;
2140 	case TIOCMBIS:
2141 		(void)commctl(com, *(int *)data, DMBIS);
2142 		break;
2143 	case TIOCMBIC:
2144 		(void)commctl(com, *(int *)data, DMBIC);
2145 		break;
2146 	case TIOCMGET:
2147 		*(int *)data = commctl(com, 0, DMGET);
2148 		break;
2149 	case TIOCMSDTRWAIT:
2150 		/* must be root since the wait applies to following logins */
2151 		error = priv_check_cred(ap->a_cred, PRIV_ROOT, 0);
2152 		if (error != 0) {
2153 			crit_exit();
2154 			lwkt_reltoken(&tty_token);
2155 			return (error);
2156 		}
2157 		com->dtr_wait = *(int *)data * hz / 100;
2158 		break;
2159 	case TIOCMGDTRWAIT:
2160 		*(int *)data = com->dtr_wait * 100 / hz;
2161 		break;
2162 	case TIOCTIMESTAMP:
2163 		com->do_timestamp = TRUE;
2164 		*(struct timeval *)data = com->timestamp;
2165 		break;
2166 	case TIOCDCDTIMESTAMP:
2167 		com->do_dcd_timestamp = TRUE;
2168 		*(struct timeval *)data = com->dcd_timestamp;
2169 		break;
2170 	default:
2171 		crit_exit();
2172 		error = pps_ioctl(ap->a_cmd, data, &com->pps);
2173 		if (error == ENODEV)
2174 			error = ENOTTY;
2175 		lwkt_reltoken(&tty_token);
2176 		return (error);
2177 	}
2178 	crit_exit();
2179 	lwkt_reltoken(&tty_token);
2180 	return (0);
2181 }
2182 
2183 static void
2184 siopoll(void *dummy, void *frame)
2185 {
2186 	int		unit;
2187 
2188 	lwkt_gettoken(&tty_token);
2189 	if (com_events == 0) {
2190 		lwkt_reltoken(&tty_token);
2191 		return;
2192 	}
2193 
2194 repeat:
2195 	for (unit = 0; unit < sio_numunits; ++unit) {
2196 		struct com_s	*com;
2197 		int		incc;
2198 		struct tty	*tp;
2199 
2200 		com = com_addr(unit);
2201 		if (com == NULL)
2202 			continue;
2203 		tp = com->tp;
2204 		if (tp == NULL || com->gone) {
2205 			/*
2206 			 * Discard any events related to never-opened or
2207 			 * going-away devices.
2208 			 */
2209 			com_lock();
2210 			incc = com->iptr - com->ibuf;
2211 			com->iptr = com->ibuf;
2212 			if (com->state & CS_CHECKMSR) {
2213 				incc += LOTS_OF_EVENTS;
2214 				com->state &= ~CS_CHECKMSR;
2215 			}
2216 			com_events -= incc;
2217 			com_unlock();
2218 			continue;
2219 		}
2220 		if (com->iptr != com->ibuf) {
2221 			com_lock();
2222 			sioinput(com);
2223 			com_unlock();
2224 		}
2225 		if (com->state & CS_CHECKMSR) {
2226 			u_char	delta_modem_status;
2227 
2228 			com_lock();
2229 			delta_modem_status = com->last_modem_status
2230 					     ^ com->prev_modem_status;
2231 			com->prev_modem_status = com->last_modem_status;
2232 			com_events -= LOTS_OF_EVENTS;
2233 			com->state &= ~CS_CHECKMSR;
2234 			com_unlock();
2235 			if (delta_modem_status & MSR_DCD)
2236 				(*linesw[tp->t_line].l_modem)
2237 					(tp, com->prev_modem_status & MSR_DCD);
2238 		}
2239 		if (com->state & CS_ODONE) {
2240 			com_lock();
2241 			com_events -= LOTS_OF_EVENTS;
2242 			com->state &= ~CS_ODONE;
2243 			com_unlock();
2244 			if (!(com->state & CS_BUSY)
2245 			    && !(com->extra_state & CSE_BUSYCHECK)) {
2246 				callout_reset(&com->busy_ch, hz / 100,
2247 						siobusycheck, com);
2248 				com->extra_state |= CSE_BUSYCHECK;
2249 			}
2250 			(*linesw[tp->t_line].l_start)(tp);
2251 		}
2252 		if (com_events == 0)
2253 			break;
2254 	}
2255 	if (com_events >= LOTS_OF_EVENTS)
2256 		goto repeat;
2257 	lwkt_reltoken(&tty_token);
2258 }
2259 
2260 /*
2261  * Called with tty_token held but no com_lock
2262  */
2263 static int
2264 comparam(struct tty *tp, struct termios *t)
2265 {
2266 	u_int		cfcr;
2267 	int		cflag;
2268 	struct com_s	*com;
2269 	u_int		divisor;
2270 	u_char		dlbh;
2271 	u_char		dlbl;
2272 	int		unit;
2273 
2274 	unit = DEV_TO_UNIT(tp->t_dev);
2275 	com = com_addr(unit);
2276 	if (com == NULL) {
2277 		return (ENODEV);
2278 	}
2279 
2280 	/* do historical conversions */
2281 	if (t->c_ispeed == 0)
2282 		t->c_ispeed = t->c_ospeed;
2283 
2284 	/* check requested parameters */
2285 	if (t->c_ospeed == 0)
2286 		divisor = 0;
2287 	else {
2288 		if (t->c_ispeed != t->c_ospeed)
2289 			return (EINVAL);
2290 		divisor = siodivisor(com->rclk, t->c_ispeed);
2291 		if (divisor == 0)
2292 			return (EINVAL);
2293 	}
2294 
2295 	/* parameters are OK, convert them to the com struct and the device */
2296 	crit_enter();
2297 	if (divisor == 0)
2298 		(void)commctl(com, TIOCM_DTR, DMBIC);	/* hang up line */
2299 	else
2300 		(void)commctl(com, TIOCM_DTR, DMBIS);
2301 	cflag = t->c_cflag;
2302 	switch (cflag & CSIZE) {
2303 	case CS5:
2304 		cfcr = CFCR_5BITS;
2305 		break;
2306 	case CS6:
2307 		cfcr = CFCR_6BITS;
2308 		break;
2309 	case CS7:
2310 		cfcr = CFCR_7BITS;
2311 		break;
2312 	default:
2313 		cfcr = CFCR_8BITS;
2314 		break;
2315 	}
2316 	if (cflag & PARENB) {
2317 		cfcr |= CFCR_PENAB;
2318 		if (!(cflag & PARODD))
2319 			cfcr |= CFCR_PEVEN;
2320 	}
2321 	if (cflag & CSTOPB)
2322 		cfcr |= CFCR_STOPB;
2323 
2324 	if (com->hasfifo && divisor != 0) {
2325 		/*
2326 		 * Use a fifo trigger level low enough so that the input
2327 		 * latency from the fifo is less than about 16 msec and
2328 		 * the total latency is less than about 30 msec.  These
2329 		 * latencies are reasonable for humans.  Serial comms
2330 		 * protocols shouldn't expect anything better since modem
2331 		 * latencies are larger.
2332 		 *
2333 		 * Interrupts can be held up for long periods of time
2334 		 * due to inefficiencies in other parts of the kernel,
2335 		 * certain video cards, etc.  Setting the FIFO trigger
2336 		 * point to MEDH instead of HIGH gives us 694uS of slop
2337 		 * (8 character times) instead of 173uS (2 character times)
2338 		 * @ 115200 bps.
2339 		 */
2340 		com->fifo_image = t->c_ospeed <= 4800
2341 				  ? FIFO_ENABLE : FIFO_ENABLE | FIFO_RX_MEDH;
2342 #ifdef COM_ESP
2343 		/*
2344 		 * The Hayes ESP card needs the fifo DMA mode bit set
2345 		 * in compatibility mode.  If not, it will interrupt
2346 		 * for each character received.
2347 		 */
2348 		if (com->esp)
2349 			com->fifo_image |= FIFO_DMA_MODE;
2350 #endif
2351 		sio_setreg(com, com_fifo, com->fifo_image);
2352 	}
2353 
2354 	/*
2355 	 * This returns with interrupts disabled so that we can complete
2356 	 * the speed change atomically.  Keeping interrupts disabled is
2357 	 * especially important while com_data is hidden.
2358 	 */
2359 	(void) siosetwater(com, t->c_ispeed);
2360 
2361 	if (divisor != 0) {
2362 		sio_setreg(com, com_cfcr, cfcr | CFCR_DLAB);
2363 		/*
2364 		 * Only set the divisor registers if they would change,
2365 		 * since on some 16550 incompatibles (UMC8669F), setting
2366 		 * them while input is arriving them loses sync until
2367 		 * data stops arriving.
2368 		 */
2369 		dlbl = divisor & 0xFF;
2370 		if (sio_getreg(com, com_dlbl) != dlbl)
2371 			sio_setreg(com, com_dlbl, dlbl);
2372 		dlbh = divisor >> 8;
2373 		if (sio_getreg(com, com_dlbh) != dlbh)
2374 			sio_setreg(com, com_dlbh, dlbh);
2375 	}
2376 
2377 	sio_setreg(com, com_cfcr, com->cfcr_image = cfcr);
2378 
2379 	if (!(tp->t_state & TS_TTSTOP))
2380 		com->state |= CS_TTGO;
2381 
2382 	if (cflag & CRTS_IFLOW) {
2383 		if (com->st16650a) {
2384 			sio_setreg(com, com_cfcr, 0xbf);
2385 			sio_setreg(com, com_fifo,
2386 				   sio_getreg(com, com_fifo) | 0x40);
2387 		}
2388 		com->state |= CS_RTS_IFLOW;
2389 		/*
2390 		 * If CS_RTS_IFLOW just changed from off to on, the change
2391 		 * needs to be propagated to MCR_RTS.  This isn't urgent,
2392 		 * so do it later by calling comstart() instead of repeating
2393 		 * a lot of code from comstart() here.
2394 		 */
2395 	} else if (com->state & CS_RTS_IFLOW) {
2396 		com->state &= ~CS_RTS_IFLOW;
2397 		/*
2398 		 * CS_RTS_IFLOW just changed from on to off.  Force MCR_RTS
2399 		 * on here, since comstart() won't do it later.
2400 		 */
2401 		outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
2402 		if (com->st16650a) {
2403 			sio_setreg(com, com_cfcr, 0xbf);
2404 			sio_setreg(com, com_fifo,
2405 				   sio_getreg(com, com_fifo) & ~0x40);
2406 		}
2407 	}
2408 
2409 
2410 	/*
2411 	 * Set up state to handle output flow control.
2412 	 * XXX - worth handling MDMBUF (DCD) flow control at the lowest level?
2413 	 * Now has 10+ msec latency, while CTS flow has 50- usec latency.
2414 	 */
2415 	com->state |= CS_ODEVREADY;
2416 	com->state &= ~CS_CTS_OFLOW;
2417 	if (cflag & CCTS_OFLOW) {
2418 		com->state |= CS_CTS_OFLOW;
2419 		if (!(com->last_modem_status & MSR_CTS))
2420 			com->state &= ~CS_ODEVREADY;
2421 		if (com->st16650a) {
2422 			sio_setreg(com, com_cfcr, 0xbf);
2423 			sio_setreg(com, com_fifo,
2424 				   sio_getreg(com, com_fifo) | 0x80);
2425 		}
2426 	} else {
2427 		if (com->st16650a) {
2428 			sio_setreg(com, com_cfcr, 0xbf);
2429 			sio_setreg(com, com_fifo,
2430 				   sio_getreg(com, com_fifo) & ~0x80);
2431 		}
2432 	}
2433 
2434 	sio_setreg(com, com_cfcr, com->cfcr_image);
2435 
2436 	/* XXX shouldn't call functions while intrs are disabled. */
2437 	disc_optim(tp, t, com);
2438 	/*
2439 	 * Recover from fiddling with CS_TTGO.  We used to call siointr1()
2440 	 * unconditionally, but that defeated the careful discarding of
2441 	 * stale input in sioopen().
2442 	 */
2443 	if (com->state >= (CS_BUSY | CS_TTGO)) {
2444 		com_lock();
2445 		siointr1(com);
2446 		com_unlock();
2447 	}
2448 	crit_exit();
2449 	comstart(tp);
2450 	if (com->ibufold != NULL) {
2451 		kfree(com->ibufold, M_DEVBUF);
2452 		com->ibufold = NULL;
2453 	}
2454 	return (0);
2455 }
2456 
2457 /*
2458  * called with tty_token held
2459  */
2460 static int
2461 siosetwater(struct com_s *com, speed_t speed)
2462 {
2463 	int		cp4ticks;
2464 	u_char		*ibuf;
2465 	int		ibufsize;
2466 	struct tty	*tp;
2467 
2468 	/*
2469 	 * Make the buffer size large enough to handle a softtty interrupt
2470 	 * latency of about 2 ticks without loss of throughput or data
2471 	 * (about 3 ticks if input flow control is not used or not honoured,
2472 	 * but a bit less for CS5-CS7 modes).
2473 	 */
2474 	cp4ticks = speed / 10 / hz * 4;
2475 	for (ibufsize = 128; ibufsize < cp4ticks;)
2476 		ibufsize <<= 1;
2477 	if (ibufsize == com->ibufsize)
2478 		return (0);
2479 
2480 	/*
2481 	 * Allocate input buffer.  The extra factor of 2 in the size is
2482 	 * to allow for an error byte for each input byte.
2483 	 */
2484 	ibuf = kmalloc(2 * ibufsize, M_DEVBUF, M_WAITOK | M_ZERO);
2485 
2486 	/* Initialize non-critical variables. */
2487 	com->ibufold = com->ibuf;
2488 	com->ibufsize = ibufsize;
2489 	tp = com->tp;
2490 	if (tp != NULL) {
2491 		tp->t_ififosize = 2 * ibufsize;
2492 		tp->t_ispeedwat = (speed_t)-1;
2493 		tp->t_ospeedwat = (speed_t)-1;
2494 	}
2495 
2496 	/*
2497 	 * Read current input buffer.
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 	com_unlock();
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_reltoken(&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 static void
2871 siocntxwait(Port_t iobase)
2872 {
2873 	int	timo;
2874 
2875 	/*
2876 	 * Wait for any pending transmission to finish.  Required to avoid
2877 	 * the UART lockup bug when the speed is changed, and for normal
2878 	 * transmits.
2879 	 */
2880 	timo = 100000;
2881 	while ((inb(iobase + com_lsr) & (LSR_TSRE | LSR_TXRDY))
2882 	       != (LSR_TSRE | LSR_TXRDY) && --timo != 0)
2883 		;
2884 }
2885 
2886 /*
2887  * Read the serial port specified and try to figure out what speed
2888  * it's currently running at.  We're assuming the serial port has
2889  * been initialized and is basicly idle.  This routine is only intended
2890  * to be run at system startup.
2891  *
2892  * If the value read from the serial port doesn't make sense, return 0.
2893  */
2894 /*
2895  * NOTE: Must be called with tty_token held
2896  */
2897 static speed_t
2898 siocngetspeed(Port_t iobase, u_long rclk)
2899 {
2900 	u_int	divisor;
2901 	u_char	dlbh;
2902 	u_char	dlbl;
2903 	u_char  cfcr;
2904 
2905 	cfcr = inb(iobase + com_cfcr);
2906 	outb(iobase + com_cfcr, CFCR_DLAB | cfcr);
2907 
2908 	dlbl = inb(iobase + com_dlbl);
2909 	dlbh = inb(iobase + com_dlbh);
2910 
2911 	outb(iobase + com_cfcr, cfcr);
2912 
2913 	divisor = dlbh << 8 | dlbl;
2914 
2915 	/* XXX there should be more sanity checking. */
2916 	if (divisor == 0)
2917 		return (CONSPEED);
2918 	return (rclk / (16UL * divisor));
2919 }
2920 
2921 static void
2922 siocnopen(struct siocnstate *sp, Port_t iobase, int speed)
2923 {
2924 	u_int	divisor;
2925 	u_char	dlbh;
2926 	u_char	dlbl;
2927 
2928 	/*
2929 	 * Save all the device control registers except the fifo register
2930 	 * and set our default ones (cs8 -parenb speed=comdefaultrate).
2931 	 * We can't save the fifo register since it is read-only.
2932 	 */
2933 	sp->ier = inb(iobase + com_ier);
2934 	outb(iobase + com_ier, 0);	/* spltty() doesn't stop siointr() */
2935 	siocntxwait(iobase);
2936 	sp->cfcr = inb(iobase + com_cfcr);
2937 	outb(iobase + com_cfcr, CFCR_DLAB | CFCR_8BITS);
2938 	sp->dlbl = inb(iobase + com_dlbl);
2939 	sp->dlbh = inb(iobase + com_dlbh);
2940 	/*
2941 	 * Only set the divisor registers if they would change, since on
2942 	 * some 16550 incompatibles (Startech), setting them clears the
2943 	 * data input register.  This also reduces the effects of the
2944 	 * UMC8669F bug.
2945 	 */
2946 	divisor = siodivisor(comdefaultrclk, speed);
2947 	dlbl = divisor & 0xFF;
2948 	if (sp->dlbl != dlbl)
2949 		outb(iobase + com_dlbl, dlbl);
2950 	dlbh = divisor >> 8;
2951 	if (sp->dlbh != dlbh)
2952 		outb(iobase + com_dlbh, dlbh);
2953 	outb(iobase + com_cfcr, CFCR_8BITS);
2954 	sp->mcr = inb(iobase + com_mcr);
2955 	/*
2956 	 * We don't want interrupts, but must be careful not to "disable"
2957 	 * them by clearing the MCR_IENABLE bit, since that might cause
2958 	 * an interrupt by floating the IRQ line.
2959 	 */
2960 	outb(iobase + com_mcr, (sp->mcr & MCR_IENABLE) | MCR_DTR | MCR_RTS);
2961 }
2962 
2963 static void
2964 siocnclose(struct siocnstate *sp, Port_t iobase)
2965 {
2966 	/*
2967 	 * Restore the device control registers.
2968 	 */
2969 	siocntxwait(iobase);
2970 	outb(iobase + com_cfcr, CFCR_DLAB | CFCR_8BITS);
2971 	if (sp->dlbl != inb(iobase + com_dlbl))
2972 		outb(iobase + com_dlbl, sp->dlbl);
2973 	if (sp->dlbh != inb(iobase + com_dlbh))
2974 		outb(iobase + com_dlbh, sp->dlbh);
2975 	outb(iobase + com_cfcr, sp->cfcr);
2976 	/*
2977 	 * XXX damp oscillations of MCR_DTR and MCR_RTS by not restoring them.
2978 	 */
2979 	outb(iobase + com_mcr, sp->mcr | MCR_DTR | MCR_RTS);
2980 	outb(iobase + com_ier, sp->ier);
2981 }
2982 
2983 static void
2984 siocnprobe(struct consdev *cp)
2985 {
2986 	speed_t			boot_speed;
2987 	u_char			cfcr;
2988 	u_int			divisor;
2989 	int			unit;
2990 	struct siocnstate	sp;
2991 
2992 	/*
2993 	 * Find our first enabled console, if any.  If it is a high-level
2994 	 * console device, then initialize it and return successfully.
2995 	 * If it is a low-level console device, then initialize it and
2996 	 * return unsuccessfully.  It must be initialized in both cases
2997 	 * for early use by console drivers and debuggers.  Initializing
2998 	 * the hardware is not necessary in all cases, since the i/o
2999 	 * routines initialize it on the fly, but it is necessary if
3000 	 * input might arrive while the hardware is switched back to an
3001 	 * uninitialized state.  We can't handle multiple console devices
3002 	 * yet because our low-level routines don't take a device arg.
3003 	 * We trust the user to set the console flags properly so that we
3004 	 * don't need to probe.
3005 	 */
3006 	cp->cn_pri = CN_DEAD;
3007 
3008 	for (unit = 0; unit < 16; unit++) { /* XXX need to know how many */
3009 		int flags;
3010 		int disabled;
3011 		if (resource_int_value("sio", unit, "disabled", &disabled) == 0) {
3012 			if (disabled)
3013 				continue;
3014 		}
3015 		if (resource_int_value("sio", unit, "flags", &flags))
3016 			continue;
3017 		if (COM_CONSOLE(flags) || COM_DEBUGGER(flags)) {
3018 			int port;
3019 			Port_t iobase;
3020 
3021 			if (resource_int_value("sio", unit, "port", &port))
3022 				continue;
3023 			iobase = port;
3024 			crit_enter();
3025 			if (boothowto & RB_SERIAL) {
3026 				boot_speed =
3027 				    siocngetspeed(iobase, comdefaultrclk);
3028 				if (boot_speed)
3029 					comdefaultrate = boot_speed;
3030 			}
3031 
3032 			/*
3033 			 * Initialize the divisor latch.  We can't rely on
3034 			 * siocnopen() to do this the first time, since it
3035 			 * avoids writing to the latch if the latch appears
3036 			 * to have the correct value.  Also, if we didn't
3037 			 * just read the speed from the hardware, then we
3038 			 * need to set the speed in hardware so that
3039 			 * switching it later is null.
3040 			 */
3041 			com_lock();
3042 			cfcr = inb(iobase + com_cfcr);
3043 			outb(iobase + com_cfcr, CFCR_DLAB | cfcr);
3044 			divisor = siodivisor(comdefaultrclk, comdefaultrate);
3045 			outb(iobase + com_dlbl, divisor & 0xff);
3046 			outb(iobase + com_dlbh, divisor >> 8);
3047 			outb(iobase + com_cfcr, cfcr);
3048 
3049 			siocnopen(&sp, iobase, comdefaultrate);
3050 			com_unlock();
3051 
3052 			crit_exit();
3053 			if (COM_CONSOLE(flags) && !COM_LLCONSOLE(flags)) {
3054 				cp->cn_probegood = 1;
3055 				cp->cn_private = (void *)(intptr_t)unit;
3056 				cp->cn_pri = COM_FORCECONSOLE(flags)
3057 					     || boothowto & RB_SERIAL
3058 					     ? CN_REMOTE : CN_NORMAL;
3059 				siocniobase = iobase;
3060 				siocnunit = unit;
3061 			}
3062 			if (COM_DEBUGGER(flags) && gdb_tab == NULL) {
3063 				kprintf("sio%d: gdb debugging port\n", unit);
3064 				siogdbiobase = iobase;
3065 				siogdbunit = unit;
3066 #if DDB > 0
3067 				cp->cn_gdbprivate = (void *)(intptr_t)unit;
3068 				gdb_tab = cp;
3069 #endif
3070 			}
3071 		}
3072 	}
3073 #if defined(__i386__) || defined(__x86_64__)
3074 #if DDB > 0
3075 	/*
3076 	 * XXX Ugly Compatability.
3077 	 * If no gdb port has been specified, set it to be the console
3078 	 * as some configuration files don't specify the gdb port.
3079 	 */
3080 	if (gdb_tab == NULL && (boothowto & RB_GDB)) {
3081 		kprintf("Warning: no GDB port specified. Defaulting to sio%d.\n",
3082 			siocnunit);
3083 		kprintf("Set flag 0x80 on desired GDB port in your\n");
3084 		kprintf("configuration file (currently sio only).\n");
3085 		siogdbiobase = siocniobase;
3086 		siogdbunit = siocnunit;
3087 		cp->cn_gdbprivate = (void *)(intptr_t)siocnunit;
3088 		gdb_tab = cp;
3089 	}
3090 #endif
3091 #endif
3092 }
3093 
3094 static void
3095 siocninit(struct consdev *cp)
3096 {
3097 	comconsole = (int)(intptr_t)cp->cn_private;
3098 }
3099 
3100 static void
3101 siocninit_fini(struct consdev *cp)
3102 {
3103 	cdev_t dev;
3104 	int unit;
3105 
3106 	if (cp->cn_probegood) {
3107 		unit = (int)(intptr_t)cp->cn_private;
3108 		/*
3109 		 * Call devfs_find_device_by_name on ttydX to find the correct device,
3110 		 * as it should have been created already at this point by the
3111 		 * attach routine.
3112 		 * If it isn't found, the serial port was not attached at all and we
3113 		 * shouldn't be here, so assert this case.
3114 		 */
3115 		dev = devfs_find_device_by_name("ttyd%r", unit);
3116 
3117 		KKASSERT(dev != NULL);
3118 		cp->cn_dev = dev;
3119 	}
3120 }
3121 
3122 static int
3123 siocncheckc(void *private)
3124 {
3125 	int	c;
3126 	int	unit = (int)(intptr_t)private;
3127 	Port_t	iobase;
3128 	struct siocnstate	sp;
3129 
3130 	if (unit == siogdbunit)
3131 		iobase = siogdbiobase;
3132 	else
3133 		iobase = siocniobase;
3134 	com_lock();
3135 	crit_enter();
3136 	siocnopen(&sp, iobase, comdefaultrate);
3137 	if (inb(iobase + com_lsr) & LSR_RXRDY)
3138 		c = inb(iobase + com_data);
3139 	else
3140 		c = -1;
3141 	siocnclose(&sp, iobase);
3142 	crit_exit();
3143 	com_unlock();
3144 	return (c);
3145 }
3146 
3147 
3148 int
3149 siocngetc(void *private)
3150 {
3151 	int	c;
3152 	int	unit = (int)(intptr_t)private;
3153 	Port_t	iobase;
3154 	struct siocnstate	sp;
3155 
3156 	if (unit == siogdbunit)
3157 		iobase = siogdbiobase;
3158 	else
3159 		iobase = siocniobase;
3160 	com_lock();
3161 	crit_enter();
3162 	siocnopen(&sp, iobase, comdefaultrate);
3163 	while (!(inb(iobase + com_lsr) & LSR_RXRDY))
3164 		;
3165 	c = inb(iobase + com_data);
3166 	siocnclose(&sp, iobase);
3167 	crit_exit();
3168 	com_unlock();
3169 	return (c);
3170 }
3171 
3172 void
3173 siocnputc(void *private, int c)
3174 {
3175 	int	unit = (int)(intptr_t)private;
3176 	struct siocnstate	sp;
3177 	Port_t	iobase;
3178 
3179 	if (unit == siogdbunit)
3180 		iobase = siogdbiobase;
3181 	else
3182 		iobase = siocniobase;
3183 	com_lock();
3184 	crit_enter();
3185 	siocnopen(&sp, iobase, comdefaultrate);
3186 	siocntxwait(iobase);
3187 	outb(iobase + com_data, c);
3188 	siocnclose(&sp, iobase);
3189 	crit_exit();
3190 	com_unlock();
3191 }
3192 
3193 DRIVER_MODULE(sio, isa, sio_isa_driver, sio_devclass, 0, 0);
3194 DRIVER_MODULE(sio, acpi, sio_isa_driver, sio_devclass, 0, 0);
3195 #if NPCI > 0
3196 DRIVER_MODULE(sio, pci, sio_pci_driver, sio_devclass, 0, 0);
3197 #endif
3198 #if NPUC > 0
3199 DRIVER_MODULE(sio, puc, sio_puc_driver, sio_devclass, 0, 0);
3200 #endif
3201