sio.c revision 182835
1/*-
2 * Copyright (c) 1991 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD: head/sys/pc98/cbus/sio.c 182835 2008-09-07 04:35:04Z nyan $
30 *	from: @(#)com.c	7.5 (Berkeley) 5/16/91
31 *	from: i386/isa sio.c,v 1.234
32 */
33
34#include "opt_comconsole.h"
35#include "opt_compat.h"
36#include "opt_gdb.h"
37#include "opt_kdb.h"
38#include "opt_sio.h"
39
40/*
41 * Serial driver, based on 386BSD-0.1 com driver.
42 * Mostly rewritten to use pseudo-DMA.
43 * Works for National Semiconductor NS8250-NS16550AF UARTs.
44 * COM driver, based on HP dca driver.
45 *
46 * Changes for PC Card integration:
47 *	- Added PC Card driver table and handlers
48 */
49/*===============================================================
50 * 386BSD(98),FreeBSD-1.1x(98) com driver.
51 * -----
52 * modified for PC9801 by M.Ishii
53 *			Kyoto University Microcomputer Club (KMC)
54 * Chou "TEFUTEFU" Hirotomi
55 *			Kyoto Univ.  the faculty of medicine
56 *===============================================================
57 * FreeBSD-2.0.1(98) sio driver.
58 * -----
59 * modified for pc98 Internal i8251 and MICRO CORE MC16550II
60 *			T.Koike(hfc01340@niftyserve.or.jp)
61 * implement kernel device configuration
62 *			aizu@orient.center.nitech.ac.jp
63 *
64 * Notes.
65 * -----
66 *  PC98 localization based on 386BSD(98) com driver. Using its PC98 local
67 *  functions.
68 *  This driver is under debugging,has bugs.
69 */
70/*
71 * modified for AIWA B98-01
72 * by T.Hatanou <hatanou@yasuda.comm.waseda.ac.jp>  last update: 15 Sep.1995
73 */
74/*
75 * Modified by Y.Takahashi of Kogakuin University.
76 */
77/*
78 * modified for 8251(FIFO) by Seigo TANIMURA <tanimura@FreeBSD.org>
79 */
80
81#include <sys/param.h>
82#include <sys/systm.h>
83#include <sys/bus.h>
84#include <sys/conf.h>
85#include <sys/fcntl.h>
86#include <sys/interrupt.h>
87#include <sys/kdb.h>
88#include <sys/kernel.h>
89#include <sys/limits.h>
90#include <sys/lock.h>
91#include <sys/malloc.h>
92#include <sys/module.h>
93#include <sys/mutex.h>
94#include <sys/proc.h>
95#include <sys/reboot.h>
96#include <sys/serial.h>
97#include <sys/sysctl.h>
98#include <sys/syslog.h>
99#include <sys/tty.h>
100#include <machine/bus.h>
101#include <sys/rman.h>
102#include <sys/timepps.h>
103#include <sys/uio.h>
104#include <sys/cons.h>
105
106#include <isa/isavar.h>
107
108#include <machine/resource.h>
109
110#include <dev/sio/sioreg.h>
111#include <dev/sio/siovar.h>
112
113#ifdef PC98
114#include <pc98/cbus/cbus.h>
115#include <pc98/pc98/pc98_machdep.h>
116#endif
117
118#ifdef COM_ESP
119#include <dev/ic/esp.h>
120#endif
121#include <dev/ic/ns16550.h>
122#ifdef PC98
123#include <dev/ic/i8251.h>
124#include <dev/ic/i8255.h>
125#include <dev/ic/rsa.h>
126#endif
127
128#define	LOTS_OF_EVENTS	64	/* helps separate urgent events from input */
129
130/*
131 * Meaning of flags:
132 *
133 * 0x00000001	shared IRQs
134 * 0x00000002	disable FIFO
135 * 0x00000008	recover sooner from lost output interrupts
136 * 0x00000010	device is potential system console
137 * 0x00000020	device is forced to become system console
138 * 0x00000040	device is reserved for low-level IO
139 * 0x00000080	use this port for remote kernel debugging
140 * 0x0000??00	minor number of master port
141 * 0x00010000	PPS timestamping on CTS instead of DCD
142 * 0x00080000	IIR_TXRDY bug
143 * 0x00400000	If no comconsole found then mark as a comconsole
144 * 0x1?000000	interface type
145 */
146
147#ifdef COM_MULTIPORT
148/* checks in flags for multiport and which is multiport "master chip"
149 * for a given card
150 */
151#define	COM_ISMULTIPORT(flags)	((flags) & 0x01)
152#define	COM_MPMASTER(flags)	(((flags) >> 8) & 0x0ff)
153#ifndef PC98
154#define	COM_NOTAST4(flags)	((flags) & 0x04)
155#endif
156#else
157#define	COM_ISMULTIPORT(flags)	(0)
158#endif /* COM_MULTIPORT */
159
160#define	COM_C_IIR_TXRDYBUG	0x80000
161#define	COM_CONSOLE(flags)	((flags) & 0x10)
162#define	COM_DEBUGGER(flags)	((flags) & 0x80)
163#ifndef PC98
164#define	COM_FIFOSIZE(flags)	(((flags) & 0xff000000) >> 24)
165#endif
166#define	COM_FORCECONSOLE(flags)	((flags) & 0x20)
167#define	COM_IIR_TXRDYBUG(flags)	((flags) & COM_C_IIR_TXRDYBUG)
168#define	COM_LLCONSOLE(flags)	((flags) & 0x40)
169#define	COM_LOSESOUTINTS(flags)	((flags) & 0x08)
170#define	COM_NOFIFO(flags)	((flags) & 0x02)
171#ifndef PC98
172#define	COM_NOSCR(flags)	((flags) & 0x100000)
173#endif
174#define	COM_PPSCTS(flags)	((flags) & 0x10000)
175#ifndef PC98
176#define	COM_ST16650A(flags)	((flags) & 0x20000)
177#define	COM_TI16754(flags)	((flags) & 0x200000)
178#endif
179
180#define	sio_getreg(com, off) \
181	(bus_space_read_1((com)->bst, (com)->bsh, (off)))
182#define	sio_setreg(com, off, value) \
183	(bus_space_write_1((com)->bst, (com)->bsh, (off), (value)))
184
185/*
186 * com state bits.
187 * (CS_BUSY | CS_TTGO) and (CS_BUSY | CS_TTGO | CS_ODEVREADY) must be higher
188 * than the other bits so that they can be tested as a group without masking
189 * off the low bits.
190 *
191 * The following com and tty flags correspond closely:
192 *	CS_BUSY		= TS_BUSY (maintained by comstart(), siopoll() and
193 *				   comstop())
194 *	CS_TTGO		= ~TS_TTSTOP (maintained by comparam() and comstart())
195 *	CS_CTS_OFLOW	= CCTS_OFLOW (maintained by comparam())
196 *	CS_RTS_IFLOW	= CRTS_IFLOW (maintained by comparam())
197 * TS_FLUSH is not used.
198 * XXX I think TIOCSETA doesn't clear TS_TTSTOP when it clears IXON.
199 * XXX CS_*FLOW should be CF_*FLOW in com->flags (control flags not state).
200 */
201#define	CS_BUSY		0x80	/* output in progress */
202#define	CS_TTGO		0x40	/* output not stopped by XOFF */
203#define	CS_ODEVREADY	0x20	/* external device h/w ready (CTS) */
204#define	CS_CHECKMSR	1	/* check of MSR scheduled */
205#define	CS_CTS_OFLOW	2	/* use CTS output flow control */
206#define	CS_ODONE	4	/* output completed */
207#define	CS_RTS_IFLOW	8	/* use RTS input flow control */
208#define	CSE_BUSYCHECK	1	/* siobusycheck() scheduled */
209
210static	char const * const	error_desc[] = {
211#define	CE_OVERRUN			0
212	"silo overflow",
213#define	CE_INTERRUPT_BUF_OVERFLOW	1
214	"interrupt-level buffer overflow",
215#define	CE_TTY_BUF_OVERFLOW		2
216	"tty-level buffer overflow",
217};
218
219#define	CE_NTYPES			3
220#define	CE_RECORD(com, errnum)		(++(com)->delta_error_counts[errnum])
221
222/* types.  XXX - should be elsewhere */
223typedef u_int	Port_t;		/* hardware port */
224typedef u_char	bool_t;		/* boolean */
225
226/* queue of linear buffers */
227struct lbq {
228	u_char	*l_head;	/* next char to process */
229	u_char	*l_tail;	/* one past the last char to process */
230	struct lbq *l_next;	/* next in queue */
231	bool_t	l_queued;	/* nonzero if queued */
232};
233
234/* com device structure */
235struct com_s {
236	u_char	state;		/* miscellaneous flag bits */
237	u_char	cfcr_image;	/* copy of value written to CFCR */
238#ifdef COM_ESP
239	bool_t	esp;		/* is this unit a hayes esp board? */
240#endif
241	u_char	extra_state;	/* more flag bits, separate for order trick */
242	u_char	fifo_image;	/* copy of value written to FIFO */
243	bool_t	hasfifo;	/* nonzero for 16550 UARTs */
244	bool_t	loses_outints;	/* nonzero if device loses output interrupts */
245	u_char	mcr_image;	/* copy of value written to MCR */
246#ifdef COM_MULTIPORT
247	bool_t	multiport;	/* is this unit part of a multiport device? */
248#endif /* COM_MULTIPORT */
249	bool_t	no_irq;		/* nonzero if irq is not attached */
250	bool_t  gone;		/* hardware disappeared */
251	bool_t	poll;		/* nonzero if polling is required */
252	bool_t	poll_output;	/* nonzero if polling for output is required */
253	bool_t	st16650a;	/* nonzero if Startech 16650A compatible */
254	int	unit;		/* unit	number */
255	u_int	flags;		/* copy of device flags */
256	u_int	tx_fifo_size;
257
258	/*
259	 * The high level of the driver never reads status registers directly
260	 * because there would be too many side effects to handle conveniently.
261	 * Instead, it reads copies of the registers stored here by the
262	 * interrupt handler.
263	 */
264	u_char	last_modem_status;	/* last MSR read by intr handler */
265	u_char	prev_modem_status;	/* last MSR handled by high level */
266
267	u_char	*ibuf;		/* start of input buffer */
268	u_char	*ibufend;	/* end of input buffer */
269	u_char	*ibufold;	/* old input buffer, to be freed */
270	u_char	*ihighwater;	/* threshold in input buffer */
271	u_char	*iptr;		/* next free spot in input buffer */
272	int	ibufsize;	/* size of ibuf (not include error bytes) */
273	int	ierroff;	/* offset of error bytes in ibuf */
274
275	struct lbq	obufq;	/* head of queue of output buffers */
276	struct lbq	obufs[2];	/* output buffers */
277
278	bus_space_tag_t		bst;
279	bus_space_handle_t	bsh;
280
281#ifdef PC98
282	Port_t	cmd_port;
283	Port_t	sts_port;
284	Port_t	in_modem_port;
285	Port_t	intr_ctrl_port;
286	Port_t	rsabase;	/* Iobase address of an I/O-DATA RSA board. */
287	int	intr_enable;
288	int	pc98_prev_modem_status;
289	int	pc98_modem_delta;
290	int	modem_car_chg_timer;
291	int	pc98_prev_siocmd;
292	int	pc98_prev_siomod;
293	int	modem_checking;
294	int	pc98_if_type;
295
296	bool_t	pc98_8251fifo;
297	bool_t	pc98_8251fifo_enable;
298#endif /* PC98 */
299	Port_t	data_port;	/* i/o ports */
300#ifdef COM_ESP
301	Port_t	esp_port;
302#endif
303	Port_t	int_ctl_port;
304	Port_t	int_id_port;
305	Port_t	modem_ctl_port;
306	Port_t	line_status_port;
307	Port_t	modem_status_port;
308
309	struct tty	*tp;	/* cross reference */
310
311	struct	pps_state pps;
312	int	pps_bit;
313#ifdef ALT_BREAK_TO_DEBUGGER
314	int	alt_brk_state;
315#endif
316
317	u_long	bytes_in;	/* statistics */
318	u_long	bytes_out;
319	u_int	delta_error_counts[CE_NTYPES];
320	u_long	error_counts[CE_NTYPES];
321
322	u_long	rclk;
323
324	struct resource *irqres;
325	struct resource *ioportres;
326	int	ioportrid;
327	void	*cookie;
328
329	/*
330	 * Data area for output buffers.  Someday we should build the output
331	 * buffer queue without copying data.
332	 */
333#ifdef PC98
334	int	obufsize;
335 	u_char	*obuf1;
336 	u_char	*obuf2;
337#else
338	u_char	obuf1[256];
339	u_char	obuf2[256];
340#endif
341};
342
343#ifdef COM_ESP
344static	int	espattach(struct com_s *com, Port_t esp_port);
345#endif
346
347static	void	combreak(struct tty *tp, int sig);
348static	timeout_t siobusycheck;
349static	u_int	siodivisor(u_long rclk, speed_t speed);
350static	void	comclose(struct tty *tp);
351static	int	comopen(struct tty *tp, struct cdev *dev);
352static	void	sioinput(struct com_s *com);
353static	void	siointr1(struct com_s *com);
354static	int	siointr(void *arg);
355static	int	commodem(struct tty *tp, int sigon, int sigoff);
356static	int	comparam(struct tty *tp, struct termios *t);
357static	void	siopoll(void *);
358static	void	siosettimeout(void);
359static	int	siosetwater(struct com_s *com, speed_t speed);
360static	void	comstart(struct tty *tp);
361static	void	comstop(struct tty *tp, int rw);
362static	timeout_t comwakeup;
363
364char		sio_driver_name[] = "sio";
365static struct	mtx sio_lock;
366static int	sio_inited;
367
368/* table and macro for fast conversion from a unit number to its com struct */
369devclass_t	sio_devclass;
370#define	com_addr(unit)	((struct com_s *) \
371			 devclass_get_softc(sio_devclass, unit)) /* XXX */
372
373int	comconsole = -1;
374static	volatile speed_t	comdefaultrate = CONSPEED;
375static	u_long			comdefaultrclk = DEFAULT_RCLK;
376SYSCTL_ULONG(_machdep, OID_AUTO, conrclk, CTLFLAG_RW, &comdefaultrclk, 0, "");
377static	speed_t			gdbdefaultrate = GDBSPEED;
378SYSCTL_UINT(_machdep, OID_AUTO, gdbspeed, CTLFLAG_RW,
379	    &gdbdefaultrate, GDBSPEED, "");
380static	u_int	com_events;	/* input chars + weighted output completions */
381static	Port_t	siocniobase;
382static	int	siocnunit = -1;
383static	void	*sio_slow_ih;
384static	void	*sio_fast_ih;
385static	int	sio_timeout;
386static	int	sio_timeouts_until_log;
387static	struct	callout_handle sio_timeout_handle
388    = CALLOUT_HANDLE_INITIALIZER(&sio_timeout_handle);
389static	int	sio_numunits;
390
391#ifdef PC98
392struct	siodev	{
393	short	if_type;
394	short	irq;
395	Port_t	cmd, sts, ctrl, mod;
396};
397static	int	sysclock;
398
399#define	COM_INT_DISABLE		{int previpri; previpri=spltty();
400#define	COM_INT_ENABLE		splx(previpri);}
401#define IEN_TxFLAG		IEN_Tx
402
403#define COM_CARRIER_DETECT_EMULATE	0
404#define	PC98_CHECK_MODEM_INTERVAL	(hz/10)
405#define DCD_OFF_TOLERANCE		2
406#define DCD_ON_RECOGNITION		2
407#define IS_8251(if_type)		(!(if_type & 0x10))
408#define COM1_EXT_CLOCK			0x40000
409
410static	void	commint(struct cdev *dev);
411static	void	com_tiocm_bis(struct com_s *com, int msr);
412static	void	com_tiocm_bic(struct com_s *com, int msr);
413static	int	com_tiocm_get(struct com_s *com);
414static	int	com_tiocm_get_delta(struct com_s *com);
415static	void	pc98_msrint_start(struct cdev *dev);
416static	void	com_cflag_and_speed_set(struct com_s *com, int cflag, int speed);
417static	int	pc98_ttspeedtab(struct com_s *com, int speed, u_int *divisor);
418static	int	pc98_get_modem_status(struct com_s *com);
419static	timeout_t	pc98_check_msr;
420static	void	pc98_set_baud_rate(struct com_s *com, u_int count);
421static	void	pc98_i8251_reset(struct com_s *com, int mode, int command);
422static	void	pc98_disable_i8251_interrupt(struct com_s *com, int mod);
423static	void	pc98_enable_i8251_interrupt(struct com_s *com, int mod);
424static	int	pc98_check_i8251_interrupt(struct com_s *com);
425static	int	pc98_i8251_get_cmd(struct com_s *com);
426static	int	pc98_i8251_get_mod(struct com_s *com);
427static	void	pc98_i8251_set_cmd(struct com_s *com, int x);
428static	void	pc98_i8251_or_cmd(struct com_s *com, int x);
429static	void	pc98_i8251_clear_cmd(struct com_s *com, int x);
430static	void	pc98_i8251_clear_or_cmd(struct com_s *com, int clr, int x);
431static	int	pc98_check_if_type(device_t dev, struct siodev *iod);
432static	int	pc98_check_8251vfast(void);
433static	int	pc98_check_8251fifo(void);
434static	void	pc98_check_sysclock(void);
435static	void	pc98_set_ioport(struct com_s *com);
436
437#define com_int_Tx_disable(com) \
438		pc98_disable_i8251_interrupt(com,IEN_Tx|IEN_TxEMP)
439#define com_int_Tx_enable(com) \
440		pc98_enable_i8251_interrupt(com,IEN_TxFLAG)
441#define com_int_Rx_disable(com) \
442		pc98_disable_i8251_interrupt(com,IEN_Rx)
443#define com_int_Rx_enable(com) \
444		pc98_enable_i8251_interrupt(com,IEN_Rx)
445#define com_int_TxRx_disable(com) \
446		pc98_disable_i8251_interrupt(com,IEN_Tx|IEN_TxEMP|IEN_Rx)
447#define com_int_TxRx_enable(com) \
448		pc98_enable_i8251_interrupt(com,IEN_TxFLAG|IEN_Rx)
449#define com_send_break_on(com) \
450		(IS_8251((com)->pc98_if_type) ? \
451		 pc98_i8251_or_cmd((com), CMD8251_SBRK) : \
452		 sio_setreg((com), com_cfcr, (com)->cfcr_image |= CFCR_SBREAK))
453#define com_send_break_off(com) \
454		(IS_8251((com)->pc98_if_type) ? \
455		 pc98_i8251_clear_cmd((com), CMD8251_SBRK) : \
456		 sio_setreg((com), com_cfcr, (com)->cfcr_image &= ~CFCR_SBREAK))
457
458static struct speedtab pc98speedtab[] = {	/* internal RS232C interface */
459	{ 0,		0, },
460	{ 50,		50, },
461	{ 75,		75, },
462	{ 150,		150, },
463	{ 200,		200, },
464	{ 300,		300, },
465	{ 600,		600, },
466	{ 1200,		1200, },
467	{ 2400,		2400, },
468	{ 4800,		4800, },
469	{ 9600,		9600, },
470	{ 19200,	19200, },
471	{ 38400,	38400, },
472	{ 51200,	51200, },
473	{ 76800,	76800, },
474	{ 20800,	20800, },
475	{ 31200,	31200, },
476	{ 41600,	41600, },
477	{ 62400,	62400, },
478	{ -1,		-1 }
479};
480static struct speedtab pc98fast_speedtab[] = {
481	{ 9600,		0x80 | (DEFAULT_RCLK / (16 * (9600))), },
482	{ 19200,	0x80 | (DEFAULT_RCLK / (16 * (19200))), },
483	{ 38400,	0x80 | (DEFAULT_RCLK / (16 * (38400))), },
484	{ 57600,	0x80 | (DEFAULT_RCLK / (16 * (57600))), },
485	{ 115200,	0x80 | (DEFAULT_RCLK / (16 * (115200))), },
486	{ -1,		-1 }
487};
488static struct speedtab comspeedtab_pio9032b[] = {
489	{ 300,		6, },
490	{ 600,		5, },
491	{ 1200,		4, },
492	{ 2400,		3, },
493	{ 4800,		2, },
494	{ 9600,		1, },
495	{ 19200,	0, },
496	{ 38400,	7, },
497	{ -1,		-1 }
498};
499static struct speedtab comspeedtab_b98_01[] = {
500	{ 75,		11, },
501	{ 150,		10, },
502	{ 300,		9, },
503	{ 600,		8, },
504	{ 1200,		7, },
505	{ 2400,		6, },
506	{ 4800,		5, },
507	{ 9600,		4, },
508	{ 19200,	3, },
509	{ 38400,	2, },
510	{ 76800,	1, },
511	{ 153600,	0, },
512	{ -1,		-1 }
513};
514static struct speedtab comspeedtab_ind[] = {
515	{ 300,		1536, },
516	{ 600,		768, },
517	{ 1200,		384, },
518	{ 2400,		192, },
519	{ 4800,		96, },
520	{ 9600,		48, },
521	{ 19200,	24, },
522	{ 38400,	12, },
523	{ 57600,	8, },
524	{ 115200,	4, },
525	{ 153600,	3, },
526	{ 230400,	2, },
527	{ 460800,	1, },
528	{ -1,		-1 }
529};
530
531struct {
532	char	*name;
533	short	port_table[7];
534	short	irr_mask;
535	struct speedtab	*speedtab;
536	short	check_irq;
537} if_8251_type[] = {
538	/* COM_IF_INTERNAL */
539	{ " (internal)", {0x30, 0x32, 0x32, 0x33, 0x35, -1, -1},
540	     -1, pc98speedtab, 1 },
541	/* COM_IF_PC9861K_1 */
542	{ " (PC9861K)", {0xb1, 0xb3, 0xb3, 0xb0, 0xb0, -1, -1},
543	     3, NULL, 1 },
544	/* COM_IF_PC9861K_2 */
545	{ " (PC9861K)", {0xb9, 0xbb, 0xbb, 0xb2, 0xb2, -1, -1},
546	      3, NULL, 1 },
547	/* COM_IF_IND_SS_1 */
548	{ " (IND-SS)", {0xb1, 0xb3, 0xb3, 0xb0, 0xb0, 0xb3, -1},
549	     3, comspeedtab_ind, 1 },
550	/* COM_IF_IND_SS_2 */
551	{ " (IND-SS)", {0xb9, 0xbb, 0xbb, 0xb2, 0xb2, 0xbb, -1},
552	     3, comspeedtab_ind, 1 },
553	/* COM_IF_PIO9032B_1 */
554	{ " (PIO9032B)", {0xb1, 0xb3, 0xb3, 0xb0, 0xb0, 0xb8, -1},
555	      7, comspeedtab_pio9032b, 1 },
556	/* COM_IF_PIO9032B_2 */
557	{ " (PIO9032B)", {0xb9, 0xbb, 0xbb, 0xb2, 0xb2, 0xba, -1},
558	      7, comspeedtab_pio9032b, 1 },
559	/* COM_IF_B98_01_1 */
560	{ " (B98-01)", {0xb1, 0xb3, 0xb3, 0xb0, 0xb0, 0xd1, 0xd3},
561	      7, comspeedtab_b98_01, 0 },
562	/* COM_IF_B98_01_2 */
563	{ " (B98-01)", {0xb9, 0xbb, 0xbb, 0xb2, 0xb2, 0xd5, 0xd7},
564	     7, comspeedtab_b98_01, 0 },
565};
566#define	PC98SIO_data_port(type)		(if_8251_type[type].port_table[0])
567#define	PC98SIO_cmd_port(type)		(if_8251_type[type].port_table[1])
568#define	PC98SIO_sts_port(type)		(if_8251_type[type].port_table[2])
569#define	PC98SIO_in_modem_port(type)	(if_8251_type[type].port_table[3])
570#define	PC98SIO_intr_ctrl_port(type)	(if_8251_type[type].port_table[4])
571#define	PC98SIO_baud_rate_port(type)	(if_8251_type[type].port_table[5])
572#define	PC98SIO_func_port(type)		(if_8251_type[type].port_table[6])
573
574#define	I8251F_data		0x130
575#define	I8251F_lsr		0x132
576#define	I8251F_msr		0x134
577#define	I8251F_iir		0x136
578#define	I8251F_fcr		0x138
579#define	I8251F_div		0x13a
580
581
582static bus_addr_t port_table_0[] =
583	{0x000, 0x001, 0x002, 0x003, 0x004, 0x005, 0x006, 0x007};
584static bus_addr_t port_table_1[] =
585	{0x000, 0x002, 0x004, 0x006, 0x008, 0x00a, 0x00c, 0x00e};
586static bus_addr_t port_table_8[] =
587	{0x000, 0x100, 0x200, 0x300, 0x400, 0x500, 0x600, 0x700};
588static bus_addr_t port_table_rsa[] = {
589	0x008, 0x009, 0x00a, 0x00b, 0x00c, 0x00d, 0x00e, 0x00f,
590	0x000, 0x001, 0x002, 0x003, 0x004, 0x005, 0x006, 0x007
591};
592
593struct {
594	char		*name;
595	short		irr_read;
596	short		irr_write;
597	bus_addr_t	*iat;
598	bus_size_t	iatsz;
599	u_long		rclk;
600} if_16550a_type[] = {
601	/* COM_IF_RSA98 */
602	{" (RSA-98)", -1, -1, port_table_0, IO_COMSIZE, DEFAULT_RCLK},
603	/* COM_IF_NS16550 */
604	{"", -1, -1, port_table_0, IO_COMSIZE, DEFAULT_RCLK},
605	/* COM_IF_SECOND_CCU */
606	{"", -1, -1, port_table_0, IO_COMSIZE, DEFAULT_RCLK},
607	/* COM_IF_MC16550II */
608	{" (MC16550II)", -1, 0x1000, port_table_8, IO_COMSIZE,
609	 DEFAULT_RCLK * 4},
610	/* COM_IF_MCRS98 */
611	{" (MC-RS98)", -1, 0x1000, port_table_8, IO_COMSIZE, DEFAULT_RCLK * 4},
612	/* COM_IF_RSB3000 */
613	{" (RSB-3000)", 0xbf, -1, port_table_1, IO_COMSIZE, DEFAULT_RCLK * 10},
614	/* COM_IF_RSB384 */
615	{" (RSB-384)", 0xbf, -1, port_table_1, IO_COMSIZE, DEFAULT_RCLK * 10},
616	/* COM_IF_MODEM_CARD */
617	{"", -1, -1, port_table_0, IO_COMSIZE, DEFAULT_RCLK},
618	/* COM_IF_RSA98III */
619	{" (RSA-98III)", -1, -1, port_table_rsa, 16, DEFAULT_RCLK * 8},
620	/* COM_IF_ESP98 */
621	{" (ESP98)", -1, -1, port_table_1, IO_COMSIZE, DEFAULT_RCLK * 4},
622};
623#endif /* PC98 */
624
625#ifdef GDB
626static	Port_t	siogdbiobase = 0;
627#endif
628
629#ifdef COM_ESP
630#ifdef PC98
631
632/* XXX configure this properly. */
633/* XXX quite broken for new-bus. */
634static  Port_t  likely_com_ports[] = { 0, 0xb0, 0xb1, 0 };
635static  Port_t  likely_esp_ports[] = { 0xc0d0, 0 };
636
637#define	ESP98_CMD1	(ESP_CMD1 * 0x100)
638#define	ESP98_CMD2	(ESP_CMD2 * 0x100)
639#define	ESP98_STATUS1	(ESP_STATUS1 * 0x100)
640#define	ESP98_STATUS2	(ESP_STATUS2 * 0x100)
641
642#else /* PC98 */
643
644/* XXX configure this properly. */
645static	Port_t	likely_com_ports[] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8, };
646static	Port_t	likely_esp_ports[] = { 0x140, 0x180, 0x280, 0 };
647
648#endif /* PC98 */
649#endif
650
651/*
652 * handle sysctl read/write requests for console speed
653 *
654 * In addition to setting comdefaultrate for I/O through /dev/console,
655 * also set the initial and lock values for the /dev/ttyXX device
656 * if there is one associated with the console.  Finally, if the /dev/tty
657 * device has already been open, change the speed on the open running port
658 * itself.
659 */
660
661static int
662sysctl_machdep_comdefaultrate(SYSCTL_HANDLER_ARGS)
663{
664	int error, s;
665	speed_t newspeed;
666	struct com_s *com;
667	struct tty *tp;
668
669	newspeed = comdefaultrate;
670
671	error = sysctl_handle_opaque(oidp, &newspeed, sizeof newspeed, req);
672	if (error || !req->newptr)
673		return (error);
674
675	comdefaultrate = newspeed;
676
677	if (comconsole < 0)		/* serial console not selected? */
678		return (0);
679
680	com = com_addr(comconsole);
681	if (com == NULL)
682		return (ENXIO);
683
684	tp = com->tp;
685	if (tp == NULL)
686		return (ENXIO);
687
688	/*
689	 * set the initial and lock rates for /dev/ttydXX and /dev/cuaXX
690	 * (note, the lock rates really are boolean -- if non-zero, disallow
691	 *  speed changes)
692	 */
693	tp->t_init_in.c_ispeed  = tp->t_init_in.c_ospeed =
694	tp->t_lock_in.c_ispeed  = tp->t_lock_in.c_ospeed =
695	tp->t_init_out.c_ispeed = tp->t_init_out.c_ospeed =
696	tp->t_lock_out.c_ispeed = tp->t_lock_out.c_ospeed = comdefaultrate;
697
698	if (tp->t_state & TS_ISOPEN) {
699		tp->t_termios.c_ispeed =
700		tp->t_termios.c_ospeed = comdefaultrate;
701		s = spltty();
702		error = comparam(tp, &tp->t_termios);
703		splx(s);
704	}
705	return error;
706}
707
708SYSCTL_PROC(_machdep, OID_AUTO, conspeed, CTLTYPE_INT | CTLFLAG_RW,
709	    0, 0, sysctl_machdep_comdefaultrate, "I", "");
710TUNABLE_INT("machdep.conspeed", __DEVOLATILE(int *, &comdefaultrate));
711
712/*
713 *	Unload the driver and clear the table.
714 *	XXX this is mostly wrong.
715 *	XXX TODO:
716 *	This is usually called when the card is ejected, but
717 *	can be caused by a kldunload of a controller driver.
718 *	The idea is to reset the driver's view of the device
719 *	and ensure that any driver entry points such as
720 *	read and write do not hang.
721 */
722int
723siodetach(device_t dev)
724{
725	struct com_s	*com;
726
727	com = (struct com_s *) device_get_softc(dev);
728	if (com == NULL) {
729		device_printf(dev, "NULL com in siounload\n");
730		return (0);
731	}
732	com->gone = TRUE;
733	if (com->tp)
734		ttyfree(com->tp);
735	if (com->irqres) {
736		bus_teardown_intr(dev, com->irqres, com->cookie);
737		bus_release_resource(dev, SYS_RES_IRQ, 0, com->irqres);
738	}
739	if (com->ioportres)
740		bus_release_resource(dev, SYS_RES_IOPORT, com->ioportrid,
741				     com->ioportres);
742	if (com->ibuf != NULL)
743		free(com->ibuf, M_DEVBUF);
744#ifdef PC98
745	if (com->obuf1 != NULL)
746		free(com->obuf1, M_DEVBUF);
747#endif
748
749	device_set_softc(dev, NULL);
750	free(com, M_DEVBUF);
751	return (0);
752}
753
754int
755sioprobe(dev, xrid, rclk, noprobe)
756	device_t	dev;
757	int		xrid;
758	u_long		rclk;
759	int		noprobe;
760{
761#if 0
762	static bool_t	already_init;
763	device_t	xdev;
764#endif
765	struct com_s	*com;
766	u_int		divisor;
767	bool_t		failures[10];
768	int		fn;
769	device_t	idev;
770	Port_t		iobase;
771	intrmask_t	irqmap[4];
772	intrmask_t	irqs;
773	u_char		mcr_image;
774	int		result;
775	u_long		xirq;
776	u_int		flags = device_get_flags(dev);
777	int		rid;
778	struct resource *port;
779#ifdef PC98
780	int		tmp;
781	struct siodev	iod;
782#endif
783
784#ifdef PC98
785	iod.if_type = GET_IFTYPE(flags);
786	if ((iod.if_type < 0 || iod.if_type > COM_IF_END1) &&
787	    (iod.if_type < 0x10 || iod.if_type > COM_IF_END2))
788			return ENXIO;
789#endif
790
791	rid = xrid;
792#ifdef PC98
793	if (IS_8251(iod.if_type)) {
794		port = bus_alloc_resource_any(dev, SYS_RES_IOPORT, &rid,
795					      RF_ACTIVE);
796	} else if (iod.if_type == COM_IF_MODEM_CARD ||
797		   iod.if_type == COM_IF_RSA98III ||
798		   isa_get_vendorid(dev)) {
799		port = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid, 0, ~0,
800		  if_16550a_type[iod.if_type & 0x0f].iatsz, RF_ACTIVE);
801	} else {
802		port = isa_alloc_resourcev(dev, SYS_RES_IOPORT, &rid,
803		   if_16550a_type[iod.if_type & 0x0f].iat,
804		   if_16550a_type[iod.if_type & 0x0f].iatsz, RF_ACTIVE);
805	}
806#else
807	port = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid,
808				  0, ~0, IO_COMSIZE, RF_ACTIVE);
809#endif
810	if (!port)
811		return (ENXIO);
812#ifdef PC98
813	if (!IS_8251(iod.if_type)) {
814		if (isa_load_resourcev(port,
815		       if_16550a_type[iod.if_type & 0x0f].iat,
816		       if_16550a_type[iod.if_type & 0x0f].iatsz) != 0) {
817			bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
818			return ENXIO;
819		}
820	}
821#endif
822
823	com = malloc(sizeof(*com), M_DEVBUF, M_NOWAIT | M_ZERO);
824	if (com == NULL) {
825		bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
826		return (ENOMEM);
827	}
828	device_set_softc(dev, com);
829	com->bst = rman_get_bustag(port);
830	com->bsh = rman_get_bushandle(port);
831#ifdef PC98
832	if (!IS_8251(iod.if_type) && rclk == 0)
833		rclk = if_16550a_type[iod.if_type & 0x0f].rclk;
834#else
835	if (rclk == 0)
836		rclk = DEFAULT_RCLK;
837#endif
838	com->rclk = rclk;
839
840	while (sio_inited != 2)
841		if (atomic_cmpset_int(&sio_inited, 0, 1)) {
842			mtx_init(&sio_lock, sio_driver_name, NULL,
843			    (comconsole != -1) ?
844			    MTX_SPIN | MTX_QUIET : MTX_SPIN);
845			atomic_store_rel_int(&sio_inited, 2);
846		}
847
848#if 0
849	/*
850	 * XXX this is broken - when we are first called, there are no
851	 * previously configured IO ports.  We could hard code
852	 * 0x3f8, 0x2f8, 0x3e8, 0x2e8 etc but that's probably worse.
853	 * This code has been doing nothing since the conversion since
854	 * "count" is zero the first time around.
855	 */
856	if (!already_init) {
857		/*
858		 * Turn off MCR_IENABLE for all likely serial ports.  An unused
859		 * port with its MCR_IENABLE gate open will inhibit interrupts
860		 * from any used port that shares the interrupt vector.
861		 * XXX the gate enable is elsewhere for some multiports.
862		 */
863		device_t *devs;
864		int count, i, xioport;
865#ifdef PC98
866		int xiftype;
867#endif
868
869		devclass_get_devices(sio_devclass, &devs, &count);
870#ifdef PC98
871		for (i = 0; i < count; i++) {
872			xdev = devs[i];
873			xioport = bus_get_resource_start(xdev, SYS_RES_IOPORT, 0);
874			xiftype = GET_IFTYPE(device_get_flags(xdev));
875			if (device_is_enabled(xdev) && xioport > 0) {
876			    if (IS_8251(xiftype))
877				outb((xioport & 0xff00) | PC98SIO_cmd_port(xiftype & 0x0f), 0xf2);
878			    else
879				outb(xioport + if_16550a_type[xiftype & 0x0f].iat[com_mcr], 0);
880			}
881		}
882#else
883		for (i = 0; i < count; i++) {
884			xdev = devs[i];
885			if (device_is_enabled(xdev) &&
886			    bus_get_resource(xdev, SYS_RES_IOPORT, 0, &xioport,
887					     NULL) == 0)
888				outb(xioport + com_mcr, 0);
889		}
890#endif
891		free(devs, M_TEMP);
892		already_init = TRUE;
893	}
894#endif
895
896	if (COM_LLCONSOLE(flags)) {
897		printf("sio%d: reserved for low-level i/o\n",
898		       device_get_unit(dev));
899		bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
900		device_set_softc(dev, NULL);
901		free(com, M_DEVBUF);
902		return (ENXIO);
903	}
904
905#ifdef PC98
906	DELAY(10);
907
908	/*
909	 * If the port is i8251 UART (internal, B98_01)
910	 */
911	if (pc98_check_if_type(dev, &iod) == -1) {
912		bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
913		device_set_softc(dev, NULL);
914		free(com, M_DEVBUF);
915		return (ENXIO);
916	}
917	if (iod.irq > 0)
918		bus_set_resource(dev, SYS_RES_IRQ, 0, iod.irq, 1);
919	if (IS_8251(iod.if_type)) {
920		outb(iod.cmd, 0);
921		DELAY(10);
922		outb(iod.cmd, 0);
923		DELAY(10);
924		outb(iod.cmd, 0);
925		DELAY(10);
926		outb(iod.cmd, CMD8251_RESET);
927		DELAY(1000);		/* for a while...*/
928		outb(iod.cmd, 0xf2);	/* MODE (dummy) */
929		DELAY(10);
930		outb(iod.cmd, 0x01);	/* CMD (dummy) */
931		DELAY(1000);		/* for a while...*/
932		if (( inb(iod.sts) & STS8251_TxEMP ) == 0 ) {
933		    result = (ENXIO);
934		}
935		if (if_8251_type[iod.if_type & 0x0f].check_irq) {
936		    COM_INT_DISABLE
937		    tmp = ( inb( iod.ctrl ) & ~(IEN_Rx|IEN_TxEMP|IEN_Tx));
938		    outb( iod.ctrl, tmp|IEN_TxEMP );
939		    DELAY(10);
940		    result = isa_irq_pending() ? 0 : ENXIO;
941		    outb( iod.ctrl, tmp );
942		    COM_INT_ENABLE
943		} else {
944		    /*
945		     * B98_01 doesn't activate TxEMP interrupt line
946		     * when being reset, so we can't check irq pending.
947		     */
948		    result = 0;
949		}
950		bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
951		if (result) {
952			device_set_softc(dev, NULL);
953			free(com, M_DEVBUF);
954		}
955		return result;
956	}
957#endif /* PC98 */
958	/*
959	 * If the device is on a multiport card and has an AST/4
960	 * compatible interrupt control register, initialize this
961	 * register and prepare to leave MCR_IENABLE clear in the mcr.
962	 * Otherwise, prepare to set MCR_IENABLE in the mcr.
963	 * Point idev to the device struct giving the correct id_irq.
964	 * This is the struct for the master device if there is one.
965	 */
966	idev = dev;
967	mcr_image = MCR_IENABLE;
968#ifdef COM_MULTIPORT
969	if (COM_ISMULTIPORT(flags)) {
970#ifndef PC98
971		Port_t xiobase;
972		u_long io;
973#endif
974
975		idev = devclass_get_device(sio_devclass, COM_MPMASTER(flags));
976		if (idev == NULL) {
977			printf("sio%d: master device %d not configured\n",
978			       device_get_unit(dev), COM_MPMASTER(flags));
979			idev = dev;
980		}
981#ifndef PC98
982		if (!COM_NOTAST4(flags)) {
983			if (bus_get_resource(idev, SYS_RES_IOPORT, 0, &io,
984					     NULL) == 0) {
985				xiobase = io;
986				if (bus_get_resource(idev, SYS_RES_IRQ, 0,
987				    NULL, NULL) == 0)
988					outb(xiobase + com_scr, 0x80);
989				else
990					outb(xiobase + com_scr, 0);
991			}
992			mcr_image = 0;
993		}
994#endif
995	}
996#endif /* COM_MULTIPORT */
997	if (bus_get_resource(idev, SYS_RES_IRQ, 0, NULL, NULL) != 0)
998		mcr_image = 0;
999
1000	bzero(failures, sizeof failures);
1001	iobase = rman_get_start(port);
1002
1003#ifdef PC98
1004        if (iod.if_type == COM_IF_RSA98III) {
1005		mcr_image = 0;
1006
1007		outb(iobase + rsa_msr,   0x04);
1008		outb(iobase + rsa_frr,   0x00);
1009		if ((inb(iobase + rsa_srr) & 0x36) != 0x36) {
1010			bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
1011			device_set_softc(dev, NULL);
1012			free(com, M_DEVBUF);
1013			return (ENXIO);
1014		}
1015		outb(iobase + rsa_ier,   0x00);
1016		outb(iobase + rsa_frr,   0x00);
1017		outb(iobase + rsa_tivsr, 0x00);
1018		outb(iobase + rsa_tcr,   0x00);
1019	}
1020
1021	tmp = if_16550a_type[iod.if_type & 0x0f].irr_write;
1022	if (tmp != -1) {
1023	    /* MC16550II */
1024	    int	irqout;
1025	    switch (isa_get_irq(idev)) {
1026	    case 3: irqout = 4; break;
1027	    case 5: irqout = 5; break;
1028	    case 6: irqout = 6; break;
1029	    case 12: irqout = 7; break;
1030	    default:
1031		printf("sio%d: irq configuration error\n",
1032		       device_get_unit(dev));
1033		bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
1034		device_set_softc(dev, NULL);
1035		free(com, M_DEVBUF);
1036		return (ENXIO);
1037	    }
1038	    outb((iobase & 0x00ff) | tmp, irqout);
1039	}
1040#endif
1041
1042	/*
1043	 * We don't want to get actual interrupts, just masked ones.
1044	 * Interrupts from this line should already be masked in the ICU,
1045	 * but mask them in the processor as well in case there are some
1046	 * (misconfigured) shared interrupts.
1047	 */
1048	mtx_lock_spin(&sio_lock);
1049/* EXTRA DELAY? */
1050
1051	/*
1052	 * Initialize the speed and the word size and wait long enough to
1053	 * drain the maximum of 16 bytes of junk in device output queues.
1054	 * The speed is undefined after a master reset and must be set
1055	 * before relying on anything related to output.  There may be
1056	 * junk after a (very fast) soft reboot and (apparently) after
1057	 * master reset.
1058	 * XXX what about the UART bug avoided by waiting in comparam()?
1059	 * We don't want to to wait long enough to drain at 2 bps.
1060	 */
1061	if (iobase == siocniobase)
1062		DELAY((16 + 1) * 1000000 / (comdefaultrate / 10));
1063	else {
1064		sio_setreg(com, com_cfcr, CFCR_DLAB | CFCR_8BITS);
1065		divisor = siodivisor(rclk, SIO_TEST_SPEED);
1066		sio_setreg(com, com_dlbl, divisor & 0xff);
1067		sio_setreg(com, com_dlbh, divisor >> 8);
1068		sio_setreg(com, com_cfcr, CFCR_8BITS);
1069		DELAY((16 + 1) * 1000000 / (SIO_TEST_SPEED / 10));
1070	}
1071
1072	/*
1073	 * Enable the interrupt gate and disable device interrupts.  This
1074	 * should leave the device driving the interrupt line low and
1075	 * guarantee an edge trigger if an interrupt can be generated.
1076	 */
1077/* EXTRA DELAY? */
1078	sio_setreg(com, com_mcr, mcr_image);
1079	sio_setreg(com, com_ier, 0);
1080	DELAY(1000);		/* XXX */
1081	irqmap[0] = isa_irq_pending();
1082
1083	/*
1084	 * Attempt to set loopback mode so that we can send a null byte
1085	 * without annoying any external device.
1086	 */
1087/* EXTRA DELAY? */
1088	sio_setreg(com, com_mcr, mcr_image | MCR_LOOPBACK);
1089
1090	/*
1091	 * Attempt to generate an output interrupt.  On 8250's, setting
1092	 * IER_ETXRDY generates an interrupt independent of the current
1093	 * setting and independent of whether the THR is empty.  On 16450's,
1094	 * setting IER_ETXRDY generates an interrupt independent of the
1095	 * current setting.  On 16550A's, setting IER_ETXRDY only
1096	 * generates an interrupt when IER_ETXRDY is not already set.
1097	 */
1098	sio_setreg(com, com_ier, IER_ETXRDY);
1099#ifdef PC98
1100        if (iod.if_type == COM_IF_RSA98III)
1101		outb(iobase + rsa_ier, 0x04);
1102#endif
1103
1104	/*
1105	 * On some 16x50 incompatibles, setting IER_ETXRDY doesn't generate
1106	 * an interrupt.  They'd better generate one for actually doing
1107	 * output.  Loopback may be broken on the same incompatibles but
1108	 * it's unlikely to do more than allow the null byte out.
1109	 */
1110	sio_setreg(com, com_data, 0);
1111	if (iobase == siocniobase)
1112		DELAY((1 + 2) * 1000000 / (comdefaultrate / 10));
1113	else
1114		DELAY((1 + 2) * 1000000 / (SIO_TEST_SPEED / 10));
1115
1116	/*
1117	 * Turn off loopback mode so that the interrupt gate works again
1118	 * (MCR_IENABLE was hidden).  This should leave the device driving
1119	 * an interrupt line high.  It doesn't matter if the interrupt
1120	 * line oscillates while we are not looking at it, since interrupts
1121	 * are disabled.
1122	 */
1123/* EXTRA DELAY? */
1124	sio_setreg(com, com_mcr, mcr_image);
1125
1126	/*
1127	 * It seems my Xircom CBEM56G Cardbus modem wants to be reset
1128	 * to 8 bits *again*, or else probe test 0 will fail.
1129	 * gwk@sgi.com, 4/19/2001
1130	 */
1131	sio_setreg(com, com_cfcr, CFCR_8BITS);
1132
1133	/*
1134	 * Some PCMCIA cards (Palido 321s, DC-1S, ...) have the "TXRDY bug",
1135	 * so we probe for a buggy IIR_TXRDY implementation even in the
1136	 * noprobe case.  We don't probe for it in the !noprobe case because
1137	 * noprobe is always set for PCMCIA cards and the problem is not
1138	 * known to affect any other cards.
1139	 */
1140	if (noprobe) {
1141		/* Read IIR a few times. */
1142		for (fn = 0; fn < 2; fn ++) {
1143			DELAY(10000);
1144			failures[6] = sio_getreg(com, com_iir);
1145		}
1146
1147		/* IIR_TXRDY should be clear.  Is it? */
1148		result = 0;
1149		if (failures[6] & IIR_TXRDY) {
1150			/*
1151			 * No.  We seem to have the bug.  Does our fix for
1152			 * it work?
1153			 */
1154			sio_setreg(com, com_ier, 0);
1155			if (sio_getreg(com, com_iir) & IIR_NOPEND) {
1156				/* Yes.  We discovered the TXRDY bug! */
1157				SET_FLAG(dev, COM_C_IIR_TXRDYBUG);
1158			} else {
1159				/* No.  Just fail.  XXX */
1160				result = ENXIO;
1161				sio_setreg(com, com_mcr, 0);
1162			}
1163		} else {
1164			/* Yes.  No bug. */
1165			CLR_FLAG(dev, COM_C_IIR_TXRDYBUG);
1166		}
1167		sio_setreg(com, com_ier, 0);
1168		sio_setreg(com, com_cfcr, CFCR_8BITS);
1169		mtx_unlock_spin(&sio_lock);
1170		bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
1171		if (iobase == siocniobase)
1172			result = 0;
1173		if (result != 0) {
1174			device_set_softc(dev, NULL);
1175			free(com, M_DEVBUF);
1176		}
1177		return (result);
1178	}
1179
1180	/*
1181	 * Check that
1182	 *	o the CFCR, IER and MCR in UART hold the values written to them
1183	 *	  (the values happen to be all distinct - this is good for
1184	 *	  avoiding false positive tests from bus echoes).
1185	 *	o an output interrupt is generated and its vector is correct.
1186	 *	o the interrupt goes away when the IIR in the UART is read.
1187	 */
1188/* EXTRA DELAY? */
1189	failures[0] = sio_getreg(com, com_cfcr) - CFCR_8BITS;
1190	failures[1] = sio_getreg(com, com_ier) - IER_ETXRDY;
1191	failures[2] = sio_getreg(com, com_mcr) - mcr_image;
1192	DELAY(10000);		/* Some internal modems need this time */
1193	irqmap[1] = isa_irq_pending();
1194	failures[4] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_TXRDY;
1195#ifdef PC98
1196        if (iod.if_type == COM_IF_RSA98III)
1197		inb(iobase + rsa_srr);
1198#endif
1199	DELAY(1000);		/* XXX */
1200	irqmap[2] = isa_irq_pending();
1201	failures[6] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_NOPEND;
1202#ifdef PC98
1203        if (iod.if_type == COM_IF_RSA98III)
1204		inb(iobase + rsa_srr);
1205#endif
1206
1207	/*
1208	 * Turn off all device interrupts and check that they go off properly.
1209	 * Leave MCR_IENABLE alone.  For ports without a master port, it gates
1210	 * the OUT2 output of the UART to
1211	 * the ICU input.  Closing the gate would give a floating ICU input
1212	 * (unless there is another device driving it) and spurious interrupts.
1213	 * (On the system that this was first tested on, the input floats high
1214	 * and gives a (masked) interrupt as soon as the gate is closed.)
1215	 */
1216	sio_setreg(com, com_ier, 0);
1217	sio_setreg(com, com_cfcr, CFCR_8BITS);	/* dummy to avoid bus echo */
1218	failures[7] = sio_getreg(com, com_ier);
1219#ifdef PC98
1220        if (iod.if_type == COM_IF_RSA98III)
1221		outb(iobase + rsa_ier, 0x00);
1222#endif
1223	DELAY(1000);		/* XXX */
1224	irqmap[3] = isa_irq_pending();
1225	failures[9] = (sio_getreg(com, com_iir) & IIR_IMASK) - IIR_NOPEND;
1226#ifdef PC98
1227        if (iod.if_type == COM_IF_RSA98III) {
1228		inb(iobase + rsa_srr);
1229		outb(iobase + rsa_frr, 0x00);
1230	}
1231#endif
1232
1233	mtx_unlock_spin(&sio_lock);
1234
1235	irqs = irqmap[1] & ~irqmap[0];
1236	if (bus_get_resource(idev, SYS_RES_IRQ, 0, &xirq, NULL) == 0 &&
1237	    ((1 << xirq) & irqs) == 0) {
1238		printf(
1239		"sio%d: configured irq %ld not in bitmap of probed irqs %#x\n",
1240		    device_get_unit(dev), xirq, irqs);
1241		printf(
1242		"sio%d: port may not be enabled\n",
1243		    device_get_unit(dev));
1244	}
1245	if (bootverbose)
1246		printf("sio%d: irq maps: %#x %#x %#x %#x\n",
1247		    device_get_unit(dev),
1248		    irqmap[0], irqmap[1], irqmap[2], irqmap[3]);
1249
1250	result = 0;
1251	for (fn = 0; fn < sizeof failures; ++fn)
1252		if (failures[fn]) {
1253			sio_setreg(com, com_mcr, 0);
1254			result = ENXIO;
1255			if (bootverbose) {
1256				printf("sio%d: probe failed test(s):",
1257				    device_get_unit(dev));
1258				for (fn = 0; fn < sizeof failures; ++fn)
1259					if (failures[fn])
1260						printf(" %d", fn);
1261				printf("\n");
1262			}
1263			break;
1264		}
1265	bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
1266	if (iobase == siocniobase)
1267		result = 0;
1268	if (result != 0) {
1269		device_set_softc(dev, NULL);
1270		free(com, M_DEVBUF);
1271	}
1272	return (result);
1273}
1274
1275#ifdef COM_ESP
1276static int
1277espattach(com, esp_port)
1278	struct com_s		*com;
1279	Port_t			esp_port;
1280{
1281	u_char	dips;
1282	u_char	val;
1283
1284	/*
1285	 * Check the ESP-specific I/O port to see if we're an ESP
1286	 * card.  If not, return failure immediately.
1287	 */
1288	if ((inb(esp_port) & 0xf3) == 0) {
1289		printf(" port 0x%x is not an ESP board?\n", esp_port);
1290		return (0);
1291	}
1292
1293	/*
1294	 * We've got something that claims to be a Hayes ESP card.
1295	 * Let's hope so.
1296	 */
1297
1298	/* Get the dip-switch configuration */
1299#ifdef PC98
1300	outb(esp_port + ESP98_CMD1, ESP_GETDIPS);
1301	dips = inb(esp_port + ESP98_STATUS1);
1302#else
1303	outb(esp_port + ESP_CMD1, ESP_GETDIPS);
1304	dips = inb(esp_port + ESP_STATUS1);
1305#endif
1306
1307	/*
1308	 * Bits 0,1 of dips say which COM port we are.
1309	 */
1310#ifdef PC98
1311	if ((rman_get_start(com->ioportres) & 0xff) ==
1312	    likely_com_ports[dips & 0x03])
1313#else
1314	if (rman_get_start(com->ioportres) == likely_com_ports[dips & 0x03])
1315#endif
1316		printf(" : ESP");
1317	else {
1318		printf(" esp_port has com %d\n", dips & 0x03);
1319		return (0);
1320	}
1321
1322	/*
1323	 * Check for ESP version 2.0 or later:  bits 4,5,6 = 010.
1324	 */
1325#ifdef PC98
1326	outb(esp_port + ESP98_CMD1, ESP_GETTEST);
1327	val = inb(esp_port + ESP98_STATUS1);	/* clear reg 1 */
1328	val = inb(esp_port + ESP98_STATUS2);
1329#else
1330	outb(esp_port + ESP_CMD1, ESP_GETTEST);
1331	val = inb(esp_port + ESP_STATUS1);	/* clear reg 1 */
1332	val = inb(esp_port + ESP_STATUS2);
1333#endif
1334	if ((val & 0x70) < 0x20) {
1335		printf("-old (%o)", val & 0x70);
1336		return (0);
1337	}
1338
1339	/*
1340	 * Check for ability to emulate 16550:  bit 7 == 1
1341	 */
1342	if ((dips & 0x80) == 0) {
1343		printf(" slave");
1344		return (0);
1345	}
1346
1347	/*
1348	 * Okay, we seem to be a Hayes ESP card.  Whee.
1349	 */
1350	com->esp = TRUE;
1351	com->esp_port = esp_port;
1352	return (1);
1353}
1354#endif /* COM_ESP */
1355
1356int
1357sioattach(dev, xrid, rclk)
1358	device_t	dev;
1359	int		xrid;
1360	u_long		rclk;
1361{
1362	struct com_s	*com;
1363#ifdef COM_ESP
1364	Port_t		*espp;
1365#endif
1366	Port_t		iobase;
1367	int		unit;
1368	u_int		flags;
1369	int		rid;
1370	struct resource *port;
1371	int		ret;
1372	int		error;
1373	struct tty	*tp;
1374#ifdef PC98
1375	u_char		*obuf;
1376	u_long		obufsize;
1377	int		if_type = GET_IFTYPE(device_get_flags(dev));
1378#endif
1379
1380	rid = xrid;
1381#ifdef PC98
1382	if (IS_8251(if_type)) {
1383		port = bus_alloc_resource_any(dev, SYS_RES_IOPORT, &rid,
1384					      RF_ACTIVE);
1385	} else if (if_type == COM_IF_MODEM_CARD ||
1386		   if_type == COM_IF_RSA98III ||
1387		   isa_get_vendorid(dev)) {
1388		port = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid, 0, ~0,
1389			  if_16550a_type[if_type & 0x0f].iatsz, RF_ACTIVE);
1390	} else {
1391		port = isa_alloc_resourcev(dev, SYS_RES_IOPORT, &rid,
1392			   if_16550a_type[if_type & 0x0f].iat,
1393			   if_16550a_type[if_type & 0x0f].iatsz, RF_ACTIVE);
1394	}
1395#else
1396	port = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid,
1397				  0, ~0, IO_COMSIZE, RF_ACTIVE);
1398#endif
1399	if (!port)
1400		return (ENXIO);
1401#ifdef PC98
1402	if (!IS_8251(if_type)) {
1403		if (isa_load_resourcev(port,
1404			       if_16550a_type[if_type & 0x0f].iat,
1405			       if_16550a_type[if_type & 0x0f].iatsz) != 0) {
1406			bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
1407			return ENXIO;
1408		}
1409	}
1410#endif
1411
1412	iobase = rman_get_start(port);
1413	unit = device_get_unit(dev);
1414	com = device_get_softc(dev);
1415	flags = device_get_flags(dev);
1416
1417	if (unit >= sio_numunits)
1418		sio_numunits = unit + 1;
1419
1420#ifdef PC98
1421	obufsize = 256;
1422	if (if_type == COM_IF_RSA98III)
1423		obufsize = 2048;
1424	if ((obuf = malloc(obufsize * 2, M_DEVBUF, M_NOWAIT)) == NULL) {
1425		bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
1426		return ENXIO;
1427	}
1428	bzero(obuf, obufsize * 2);
1429#endif
1430
1431	/*
1432	 * sioprobe() has initialized the device registers as follows:
1433	 *	o cfcr = CFCR_8BITS.
1434	 *	  It is most important that CFCR_DLAB is off, so that the
1435	 *	  data port is not hidden when we enable interrupts.
1436	 *	o ier = 0.
1437	 *	  Interrupts are only enabled when the line is open.
1438	 *	o mcr = MCR_IENABLE, or 0 if the port has AST/4 compatible
1439	 *	  interrupt control register or the config specifies no irq.
1440	 *	  Keeping MCR_DTR and MCR_RTS off might stop the external
1441	 *	  device from sending before we are ready.
1442	 */
1443	bzero(com, sizeof *com);
1444	com->unit = unit;
1445	com->ioportres = port;
1446	com->ioportrid = rid;
1447	com->bst = rman_get_bustag(port);
1448	com->bsh = rman_get_bushandle(port);
1449	com->cfcr_image = CFCR_8BITS;
1450	com->loses_outints = COM_LOSESOUTINTS(flags) != 0;
1451	com->no_irq = bus_get_resource(dev, SYS_RES_IRQ, 0, NULL, NULL) != 0;
1452	com->tx_fifo_size = 1;
1453#ifdef PC98
1454	com->obufsize = obufsize;
1455	com->obuf1 = obuf;
1456	com->obuf2 = obuf + obufsize;
1457#endif
1458	com->obufs[0].l_head = com->obuf1;
1459	com->obufs[1].l_head = com->obuf2;
1460
1461#ifdef PC98
1462	com->pc98_if_type = if_type;
1463
1464	if (IS_8251(if_type)) {
1465	    pc98_set_ioport(com);
1466
1467	    if (if_type == COM_IF_INTERNAL && pc98_check_8251fifo()) {
1468		com->pc98_8251fifo = 1;
1469		com->pc98_8251fifo_enable = 0;
1470	    }
1471	} else {
1472	    bus_addr_t	*iat = if_16550a_type[if_type & 0x0f].iat;
1473
1474	    com->data_port = iobase + iat[com_data];
1475	    com->int_ctl_port = iobase + iat[com_ier];
1476	    com->int_id_port = iobase + iat[com_iir];
1477	    com->modem_ctl_port = iobase + iat[com_mcr];
1478	    com->mcr_image = inb(com->modem_ctl_port);
1479	    com->line_status_port = iobase + iat[com_lsr];
1480	    com->modem_status_port = iobase + iat[com_msr];
1481	}
1482#else /* not PC98 */
1483	com->data_port = iobase + com_data;
1484	com->int_ctl_port = iobase + com_ier;
1485	com->int_id_port = iobase + com_iir;
1486	com->modem_ctl_port = iobase + com_mcr;
1487	com->mcr_image = inb(com->modem_ctl_port);
1488	com->line_status_port = iobase + com_lsr;
1489	com->modem_status_port = iobase + com_msr;
1490#endif
1491
1492	tp = com->tp = ttyalloc();
1493	tp->t_oproc = comstart;
1494	tp->t_param = comparam;
1495	tp->t_stop = comstop;
1496	tp->t_modem = commodem;
1497	tp->t_break = combreak;
1498	tp->t_close = comclose;
1499	tp->t_open = comopen;
1500	tp->t_sc = com;
1501
1502#ifdef PC98
1503	if (!IS_8251(if_type) && rclk == 0)
1504		rclk = if_16550a_type[if_type & 0x0f].rclk;
1505#else
1506	if (rclk == 0)
1507		rclk = DEFAULT_RCLK;
1508#endif
1509	com->rclk = rclk;
1510
1511	if (unit == comconsole)
1512		ttyconsolemode(tp, comdefaultrate);
1513	error = siosetwater(com, tp->t_init_in.c_ispeed);
1514	mtx_unlock_spin(&sio_lock);
1515	if (error) {
1516		/*
1517		 * Leave i/o resources allocated if this is a `cn'-level
1518		 * console, so that other devices can't snarf them.
1519		 */
1520		if (iobase != siocniobase)
1521			bus_release_resource(dev, SYS_RES_IOPORT, rid, port);
1522		return (ENOMEM);
1523	}
1524
1525	/* attempt to determine UART type */
1526	printf("sio%d: type", unit);
1527
1528#ifndef PC98
1529	if (!COM_ISMULTIPORT(flags) &&
1530	    !COM_IIR_TXRDYBUG(flags) && !COM_NOSCR(flags)) {
1531		u_char	scr;
1532		u_char	scr1;
1533		u_char	scr2;
1534
1535		scr = sio_getreg(com, com_scr);
1536		sio_setreg(com, com_scr, 0xa5);
1537		scr1 = sio_getreg(com, com_scr);
1538		sio_setreg(com, com_scr, 0x5a);
1539		scr2 = sio_getreg(com, com_scr);
1540		sio_setreg(com, com_scr, scr);
1541		if (scr1 != 0xa5 || scr2 != 0x5a) {
1542			printf(" 8250 or not responding");
1543			goto determined_type;
1544		}
1545	}
1546#endif /* !PC98 */
1547#ifdef PC98
1548	if (IS_8251(com->pc98_if_type)) {
1549	    if (com->pc98_8251fifo && !COM_NOFIFO(flags))
1550		com->tx_fifo_size = 16;
1551	    com_int_TxRx_disable( com );
1552	    com_cflag_and_speed_set( com, tp->t_init_in.c_cflag, comdefaultrate );
1553	    com_tiocm_bic( com, TIOCM_DTR|TIOCM_RTS|TIOCM_LE );
1554	    com_send_break_off( com );
1555
1556	    if (com->pc98_if_type == COM_IF_INTERNAL) {
1557		printf(" (internal%s%s)",
1558		       com->pc98_8251fifo ? " fifo" : "",
1559		       PC98SIO_baud_rate_port(com->pc98_if_type) != -1 ?
1560		       " v-fast" : "");
1561	    } else {
1562		printf(" 8251%s", if_8251_type[com->pc98_if_type & 0x0f].name);
1563	    }
1564	} else {
1565#endif /* PC98 */
1566	sio_setreg(com, com_fifo, FIFO_ENABLE | FIFO_RX_HIGH);
1567	DELAY(100);
1568	switch (inb(com->int_id_port) & IIR_FIFO_MASK) {
1569	case FIFO_RX_LOW:
1570		printf(" 16450");
1571		break;
1572	case FIFO_RX_MEDL:
1573		printf(" 16450?");
1574		break;
1575	case FIFO_RX_MEDH:
1576		printf(" 16550?");
1577		break;
1578	case FIFO_RX_HIGH:
1579		if (COM_NOFIFO(flags)) {
1580			printf(" 16550A fifo disabled");
1581			break;
1582		}
1583		com->hasfifo = TRUE;
1584#ifdef PC98
1585		if (com->pc98_if_type == COM_IF_RSA98III) {
1586			com->tx_fifo_size = 2048;
1587			com->rsabase = iobase;
1588			outb(com->rsabase + rsa_ier, 0x00);
1589			outb(com->rsabase + rsa_frr, 0x00);
1590		}
1591#else
1592		if (COM_ST16650A(flags)) {
1593			printf(" ST16650A");
1594			com->st16650a = TRUE;
1595			com->tx_fifo_size = 32;
1596			break;
1597		}
1598		if (COM_TI16754(flags)) {
1599			printf(" TI16754");
1600			com->tx_fifo_size = 64;
1601			break;
1602		}
1603#endif
1604		printf(" 16550A");
1605#ifdef COM_ESP
1606#ifdef PC98
1607		if (com->pc98_if_type == COM_IF_ESP98)
1608#endif
1609		for (espp = likely_esp_ports; *espp != 0; espp++)
1610			if (espattach(com, *espp)) {
1611				com->tx_fifo_size = 1024;
1612				break;
1613			}
1614		if (com->esp)
1615			break;
1616#endif
1617#ifdef PC98
1618		com->tx_fifo_size = 16;
1619#else
1620		com->tx_fifo_size = COM_FIFOSIZE(flags);
1621		if (com->tx_fifo_size == 0)
1622			com->tx_fifo_size = 16;
1623		else
1624			printf(" lookalike with %u bytes FIFO",
1625			       com->tx_fifo_size);
1626#endif
1627		break;
1628	}
1629
1630#ifdef PC98
1631	if (com->pc98_if_type == COM_IF_RSB3000) {
1632	    /* Set RSB-2000/3000 Extended Buffer mode. */
1633	    u_char lcr;
1634	    lcr = sio_getreg(com, com_cfcr);
1635	    sio_setreg(com, com_cfcr, lcr | CFCR_DLAB);
1636	    sio_setreg(com, com_emr, EMR_EXBUFF | EMR_EFMODE);
1637	    sio_setreg(com, com_cfcr, lcr);
1638	}
1639#endif
1640
1641#ifdef COM_ESP
1642	if (com->esp) {
1643		/*
1644		 * Set 16550 compatibility mode.
1645		 * We don't use the ESP_MODE_SCALE bit to increase the
1646		 * fifo trigger levels because we can't handle large
1647		 * bursts of input.
1648		 * XXX flow control should be set in comparam(), not here.
1649		 */
1650#ifdef PC98
1651		outb(com->esp_port + ESP98_CMD1, ESP_SETMODE);
1652		outb(com->esp_port + ESP98_CMD2, ESP_MODE_RTS | ESP_MODE_FIFO);
1653#else
1654		outb(com->esp_port + ESP_CMD1, ESP_SETMODE);
1655		outb(com->esp_port + ESP_CMD2, ESP_MODE_RTS | ESP_MODE_FIFO);
1656#endif
1657
1658		/* Set RTS/CTS flow control. */
1659#ifdef PC98
1660		outb(com->esp_port + ESP98_CMD1, ESP_SETFLOWTYPE);
1661		outb(com->esp_port + ESP98_CMD2, ESP_FLOW_RTS);
1662		outb(com->esp_port + ESP98_CMD2, ESP_FLOW_CTS);
1663#else
1664		outb(com->esp_port + ESP_CMD1, ESP_SETFLOWTYPE);
1665		outb(com->esp_port + ESP_CMD2, ESP_FLOW_RTS);
1666		outb(com->esp_port + ESP_CMD2, ESP_FLOW_CTS);
1667#endif
1668
1669		/* Set flow-control levels. */
1670#ifdef PC98
1671		outb(com->esp_port + ESP98_CMD1, ESP_SETRXFLOW);
1672		outb(com->esp_port + ESP98_CMD2, HIBYTE(768));
1673		outb(com->esp_port + ESP98_CMD2, LOBYTE(768));
1674		outb(com->esp_port + ESP98_CMD2, HIBYTE(512));
1675		outb(com->esp_port + ESP98_CMD2, LOBYTE(512));
1676#else
1677		outb(com->esp_port + ESP_CMD1, ESP_SETRXFLOW);
1678		outb(com->esp_port + ESP_CMD2, HIBYTE(768));
1679		outb(com->esp_port + ESP_CMD2, LOBYTE(768));
1680		outb(com->esp_port + ESP_CMD2, HIBYTE(512));
1681		outb(com->esp_port + ESP_CMD2, LOBYTE(512));
1682#endif
1683
1684#ifdef PC98
1685                /* Set UART clock prescaler. */
1686                outb(com->esp_port + ESP98_CMD1, ESP_SETCLOCK);
1687                outb(com->esp_port + ESP98_CMD2, 2);	/* 4 times */
1688#endif
1689	}
1690#endif /* COM_ESP */
1691	sio_setreg(com, com_fifo, 0);
1692#ifdef PC98
1693	printf("%s", if_16550a_type[com->pc98_if_type & 0x0f].name);
1694#else
1695determined_type: ;
1696#endif
1697
1698#ifdef COM_MULTIPORT
1699	if (COM_ISMULTIPORT(flags)) {
1700		device_t masterdev;
1701
1702		com->multiport = TRUE;
1703		printf(" (multiport");
1704		if (unit == COM_MPMASTER(flags))
1705			printf(" master");
1706		printf(")");
1707		masterdev = devclass_get_device(sio_devclass,
1708		    COM_MPMASTER(flags));
1709		com->no_irq = (masterdev == NULL || bus_get_resource(masterdev,
1710		    SYS_RES_IRQ, 0, NULL, NULL) != 0);
1711	 }
1712#endif /* COM_MULTIPORT */
1713#ifdef PC98
1714	}
1715#endif
1716	if (unit == comconsole)
1717		printf(", console");
1718	if (COM_IIR_TXRDYBUG(flags))
1719		printf(" with a buggy IIR_TXRDY implementation");
1720	printf("\n");
1721
1722	if (sio_fast_ih == NULL) {
1723		swi_add(&tty_intr_event, "sio", siopoll, NULL, SWI_TTY, 0,
1724		    &sio_fast_ih);
1725		swi_add(&clk_intr_event, "sio", siopoll, NULL, SWI_CLOCK, 0,
1726		    &sio_slow_ih);
1727	}
1728
1729	com->flags = flags;
1730	com->pps.ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR;
1731	tp->t_pps = &com->pps;
1732
1733	if (COM_PPSCTS(flags))
1734		com->pps_bit = MSR_CTS;
1735	else
1736		com->pps_bit = MSR_DCD;
1737	pps_init(&com->pps);
1738
1739	rid = 0;
1740	com->irqres = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, RF_ACTIVE);
1741	if (com->irqres) {
1742		ret = bus_setup_intr(dev, com->irqres,
1743				     INTR_TYPE_TTY,
1744				     siointr, NULL, com, &com->cookie);
1745		if (ret) {
1746			ret = bus_setup_intr(dev,
1747					     com->irqres, INTR_TYPE_TTY,
1748					     NULL, (driver_intr_t *)siointr,
1749					     com, &com->cookie);
1750			if (ret == 0)
1751				device_printf(dev, "unable to activate interrupt in fast mode - using normal mode\n");
1752		}
1753		if (ret)
1754			device_printf(dev, "could not activate interrupt\n");
1755#if defined(KDB) && (defined(BREAK_TO_DEBUGGER) || \
1756    defined(ALT_BREAK_TO_DEBUGGER))
1757		/*
1758		 * Enable interrupts for early break-to-debugger support
1759		 * on the console.
1760		 */
1761		if (ret == 0 && unit == comconsole)
1762			outb(siocniobase + com_ier, IER_ERXRDY | IER_ERLS |
1763			    IER_EMSC);
1764#endif
1765	}
1766
1767	/* We're ready, open the doors... */
1768	ttycreate(tp, TS_CALLOUT, "d%r", unit);
1769
1770	return (0);
1771}
1772
1773static int
1774comopen(struct tty *tp, struct cdev *dev)
1775{
1776	struct com_s	*com;
1777	int i;
1778
1779	com = tp->t_sc;
1780	com->poll = com->no_irq;
1781	com->poll_output = com->loses_outints;
1782#ifdef PC98
1783	if (IS_8251(com->pc98_if_type)) {
1784		com_tiocm_bis(com, TIOCM_DTR|TIOCM_RTS);
1785		pc98_msrint_start(dev);
1786		if (com->pc98_8251fifo) {
1787			com->pc98_8251fifo_enable = 1;
1788			outb(I8251F_fcr,
1789			     FIFO_ENABLE | FIFO_XMT_RST | FIFO_RCV_RST);
1790		}
1791	}
1792#endif
1793	if (com->hasfifo) {
1794		/*
1795		 * (Re)enable and drain fifos.
1796		 *
1797		 * Certain SMC chips cause problems if the fifos
1798		 * are enabled while input is ready.  Turn off the
1799		 * fifo if necessary to clear the input.  We test
1800		 * the input ready bit after enabling the fifos
1801		 * since we've already enabled them in comparam()
1802		 * and to handle races between enabling and fresh
1803		 * input.
1804		 */
1805		for (i = 0; i < 500; i++) {
1806			sio_setreg(com, com_fifo,
1807			    FIFO_RCV_RST | FIFO_XMT_RST | com->fifo_image);
1808#ifdef PC98
1809			if (com->pc98_if_type == COM_IF_RSA98III)
1810				outb(com->rsabase + rsa_frr , 0x00);
1811#endif
1812			/*
1813			 * XXX the delays are for superstitious
1814			 * historical reasons.  It must be less than
1815			 * the character time at the maximum
1816			 * supported speed (87 usec at 115200 bps
1817			 * 8N1).  Otherwise we might loop endlessly
1818			 * if data is streaming in.  We used to use
1819			 * delays of 100.  That usually worked
1820			 * because DELAY(100) used to usually delay
1821			 * for about 85 usec instead of 100.
1822			 */
1823			DELAY(50);
1824#ifdef PC98
1825			if (com->pc98_if_type == COM_IF_RSA98III ?
1826			    !(inb(com->rsabase + rsa_srr) & 0x08) :
1827			    !(inb(com->line_status_port) & LSR_RXRDY))
1828				break;
1829#else
1830			if (!(inb(com->line_status_port) & LSR_RXRDY))
1831				break;
1832#endif
1833			sio_setreg(com, com_fifo, 0);
1834			DELAY(50);
1835			(void) inb(com->data_port);
1836		}
1837		if (i == 500)
1838			return (EIO);
1839	}
1840
1841	mtx_lock_spin(&sio_lock);
1842#ifdef PC98
1843	if (IS_8251(com->pc98_if_type)) {
1844		com_tiocm_bis(com, TIOCM_LE);
1845		com->pc98_prev_modem_status = pc98_get_modem_status(com);
1846		com_int_Rx_enable(com);
1847	} else {
1848#endif
1849	(void) inb(com->line_status_port);
1850	(void) inb(com->data_port);
1851	com->prev_modem_status = com->last_modem_status
1852	    = inb(com->modem_status_port);
1853	outb(com->int_ctl_port,
1854	     IER_ERXRDY | IER_ERLS | IER_EMSC
1855	     | (COM_IIR_TXRDYBUG(com->flags) ? 0 : IER_ETXRDY));
1856#ifdef PC98
1857	if (com->pc98_if_type == COM_IF_RSA98III) {
1858		outb(com->rsabase + rsa_ier, 0x1d);
1859		outb(com->int_ctl_port, IER_ERLS | IER_EMSC);
1860	}
1861#endif
1862#ifdef PC98
1863	}
1864#endif
1865	mtx_unlock_spin(&sio_lock);
1866	siosettimeout();
1867	/* XXX: should be generic ? */
1868#ifdef PC98
1869	if ((IS_8251(com->pc98_if_type) &&
1870	     (pc98_get_modem_status(com) & TIOCM_CAR)) ||
1871	    (!IS_8251(com->pc98_if_type) &&
1872	     (com->prev_modem_status & MSR_DCD)) ||
1873	    ISCALLOUT(dev))
1874		ttyld_modem(tp, 1);
1875#else
1876	if (com->prev_modem_status & MSR_DCD || ISCALLOUT(dev))
1877		ttyld_modem(tp, 1);
1878#endif
1879	return (0);
1880}
1881
1882static void
1883comclose(tp)
1884	struct tty	*tp;
1885{
1886	int		s;
1887	struct com_s	*com;
1888
1889	s = spltty();
1890	com = tp->t_sc;
1891	com->poll = FALSE;
1892	com->poll_output = FALSE;
1893#ifdef PC98
1894	com_send_break_off(com);
1895#else
1896	sio_setreg(com, com_cfcr, com->cfcr_image &= ~CFCR_SBREAK);
1897#endif
1898
1899#if defined(KDB) && (defined(BREAK_TO_DEBUGGER) || \
1900    defined(ALT_BREAK_TO_DEBUGGER))
1901	/*
1902	 * Leave interrupts enabled and don't clear DTR if this is the
1903	 * console. This allows us to detect break-to-debugger events
1904	 * while the console device is closed.
1905	 */
1906	if (com->unit != comconsole)
1907#endif
1908	{
1909#ifdef PC98
1910		int	tmp;
1911		if (IS_8251(com->pc98_if_type))
1912			com_int_TxRx_disable(com);
1913		else
1914			sio_setreg(com, com_ier, 0);
1915		if (com->pc98_if_type == COM_IF_RSA98III)
1916			outb(com->rsabase + rsa_ier, 0x00);
1917		if (IS_8251(com->pc98_if_type))
1918			tmp = pc98_get_modem_status(com) & TIOCM_CAR;
1919		else
1920			tmp = com->prev_modem_status & MSR_DCD;
1921#else
1922		sio_setreg(com, com_ier, 0);
1923#endif
1924		if (tp->t_cflag & HUPCL
1925		    /*
1926		     * XXX we will miss any carrier drop between here and the
1927		     * next open.  Perhaps we should watch DCD even when the
1928		     * port is closed; it is not sufficient to check it at
1929		     * the next open because it might go up and down while
1930		     * we're not watching.
1931		     */
1932		    || (!tp->t_actout
1933#ifdef PC98
1934			&& !(tmp)
1935#else
1936		        && !(com->prev_modem_status & MSR_DCD)
1937#endif
1938		        && !(tp->t_init_in.c_cflag & CLOCAL))
1939		    || !(tp->t_state & TS_ISOPEN)) {
1940#ifdef PC98
1941			if (IS_8251(com->pc98_if_type))
1942			    com_tiocm_bic(com, TIOCM_DTR|TIOCM_RTS|TIOCM_LE);
1943			else
1944#endif
1945			(void)commodem(tp, 0, SER_DTR);
1946			ttydtrwaitstart(tp);
1947		}
1948#ifdef PC98
1949		else {
1950			if (IS_8251(com->pc98_if_type))
1951				com_tiocm_bic(com, TIOCM_LE);
1952		}
1953#endif
1954	}
1955#ifdef PC98
1956	if (com->pc98_8251fifo)	{
1957	    if (com->pc98_8251fifo_enable)
1958		outb(I8251F_fcr, FIFO_XMT_RST | FIFO_RCV_RST);
1959	    com->pc98_8251fifo_enable = 0;
1960	}
1961#endif
1962	if (com->hasfifo) {
1963		/*
1964		 * Disable fifos so that they are off after controlled
1965		 * reboots.  Some BIOSes fail to detect 16550s when the
1966		 * fifos are enabled.
1967		 */
1968		sio_setreg(com, com_fifo, 0);
1969	}
1970	tp->t_actout = FALSE;
1971	wakeup(&tp->t_actout);
1972	wakeup(TSA_CARR_ON(tp));	/* restart any wopeners */
1973	siosettimeout();
1974	splx(s);
1975}
1976
1977static void
1978siobusycheck(chan)
1979	void	*chan;
1980{
1981	struct com_s	*com;
1982	int		s;
1983
1984	com = (struct com_s *)chan;
1985
1986	/*
1987	 * Clear TS_BUSY if low-level output is complete.
1988	 * spl locking is sufficient because siointr1() does not set CS_BUSY.
1989	 * If siointr1() clears CS_BUSY after we look at it, then we'll get
1990	 * called again.  Reading the line status port outside of siointr1()
1991	 * is safe because CS_BUSY is clear so there are no output interrupts
1992	 * to lose.
1993	 */
1994	s = spltty();
1995	if (com->state & CS_BUSY)
1996		com->extra_state &= ~CSE_BUSYCHECK;	/* False alarm. */
1997#ifdef	PC98
1998	else if ((IS_8251(com->pc98_if_type) &&
1999		  ((com->pc98_8251fifo_enable &&
2000		    (inb(I8251F_lsr) & (FLSR_TxRDY | FLSR_TxEMP))
2001		    == (FLSR_TxRDY | FLSR_TxEMP)) ||
2002		   (!com->pc98_8251fifo_enable &&
2003		    (inb(com->sts_port) & (STS8251_TxRDY | STS8251_TxEMP))
2004		    == (STS8251_TxRDY | STS8251_TxEMP)))) ||
2005		 ((inb(com->line_status_port) & (LSR_TSRE | LSR_TXRDY))
2006		  == (LSR_TSRE | LSR_TXRDY))) {
2007#else
2008	else if ((inb(com->line_status_port) & (LSR_TSRE | LSR_TXRDY))
2009	    == (LSR_TSRE | LSR_TXRDY)) {
2010#endif
2011		com->tp->t_state &= ~TS_BUSY;
2012		ttwwakeup(com->tp);
2013		com->extra_state &= ~CSE_BUSYCHECK;
2014	} else
2015		timeout(siobusycheck, com, hz / 100);
2016	splx(s);
2017}
2018
2019static u_int
2020siodivisor(rclk, speed)
2021	u_long	rclk;
2022	speed_t	speed;
2023{
2024	long	actual_speed;
2025	u_int	divisor;
2026	int	error;
2027
2028	if (speed == 0)
2029		return (0);
2030#if UINT_MAX > (ULONG_MAX - 1) / 8
2031	if (speed > (ULONG_MAX - 1) / 8)
2032		return (0);
2033#endif
2034	divisor = (rclk / (8UL * speed) + 1) / 2;
2035	if (divisor == 0 || divisor >= 65536)
2036		return (0);
2037	actual_speed = rclk / (16UL * divisor);
2038
2039	/* 10 times error in percent: */
2040	error = ((actual_speed - (long)speed) * 2000 / (long)speed + 1) / 2;
2041
2042	/* 3.0% maximum error tolerance: */
2043	if (error < -30 || error > 30)
2044		return (0);
2045
2046	return (divisor);
2047}
2048
2049/*
2050 * Call this function with the sio_lock mutex held.  It will return with the
2051 * lock still held.
2052 */
2053static void
2054sioinput(com)
2055	struct com_s	*com;
2056{
2057	u_char		*buf;
2058	int		incc;
2059	u_char		line_status;
2060	int		recv_data;
2061	struct tty	*tp;
2062
2063	buf = com->ibuf;
2064	tp = com->tp;
2065	if (!(tp->t_state & TS_ISOPEN) || !(tp->t_cflag & CREAD)) {
2066		com_events -= (com->iptr - com->ibuf);
2067		com->iptr = com->ibuf;
2068		return;
2069	}
2070	if (tp->t_state & TS_CAN_BYPASS_L_RINT) {
2071		/*
2072		 * Avoid the grotesquely inefficient lineswitch routine
2073		 * (ttyinput) in "raw" mode.  It usually takes about 450
2074		 * instructions (that's without canonical processing or echo!).
2075		 * slinput is reasonably fast (usually 40 instructions plus
2076		 * call overhead).
2077		 */
2078		do {
2079			/*
2080			 * This may look odd, but it is using save-and-enable
2081			 * semantics instead of the save-and-disable semantics
2082			 * that are used everywhere else.
2083			 */
2084			mtx_unlock_spin(&sio_lock);
2085			incc = com->iptr - buf;
2086			if (tp->t_rawq.c_cc + incc > tp->t_ihiwat
2087			    && (com->state & CS_RTS_IFLOW
2088				|| tp->t_iflag & IXOFF)
2089			    && !(tp->t_state & TS_TBLOCK))
2090				ttyblock(tp);
2091			com->delta_error_counts[CE_TTY_BUF_OVERFLOW]
2092				+= b_to_q((char *)buf, incc, &tp->t_rawq);
2093			buf += incc;
2094			tk_nin += incc;
2095			tk_rawcc += incc;
2096			tp->t_rawcc += incc;
2097			ttwakeup(tp);
2098			if (tp->t_state & TS_TTSTOP
2099			    && (tp->t_iflag & IXANY
2100				|| tp->t_cc[VSTART] == tp->t_cc[VSTOP])) {
2101				tp->t_state &= ~TS_TTSTOP;
2102				tp->t_lflag &= ~FLUSHO;
2103				comstart(tp);
2104			}
2105			mtx_lock_spin(&sio_lock);
2106		} while (buf < com->iptr);
2107	} else {
2108		do {
2109			/*
2110			 * This may look odd, but it is using save-and-enable
2111			 * semantics instead of the save-and-disable semantics
2112			 * that are used everywhere else.
2113			 */
2114			mtx_unlock_spin(&sio_lock);
2115			line_status = buf[com->ierroff];
2116			recv_data = *buf++;
2117			if (line_status
2118			    & (LSR_BI | LSR_FE | LSR_OE | LSR_PE)) {
2119				if (line_status & LSR_BI)
2120					recv_data |= TTY_BI;
2121				if (line_status & LSR_FE)
2122					recv_data |= TTY_FE;
2123				if (line_status & LSR_OE)
2124					recv_data |= TTY_OE;
2125				if (line_status & LSR_PE)
2126					recv_data |= TTY_PE;
2127			}
2128			ttyld_rint(tp, recv_data);
2129			mtx_lock_spin(&sio_lock);
2130		} while (buf < com->iptr);
2131	}
2132	com_events -= (com->iptr - com->ibuf);
2133	com->iptr = com->ibuf;
2134
2135	/*
2136	 * There is now room for another low-level buffer full of input,
2137	 * so enable RTS if it is now disabled and there is room in the
2138	 * high-level buffer.
2139	 */
2140#ifdef PC98
2141	if (IS_8251(com->pc98_if_type)) {
2142		if ((com->state & CS_RTS_IFLOW) &&
2143		    !(com_tiocm_get(com) & TIOCM_RTS) &&
2144		    !(tp->t_state & TS_TBLOCK))
2145			com_tiocm_bis(com, TIOCM_RTS);
2146	} else {
2147		if ((com->state & CS_RTS_IFLOW) &&
2148		    !(com->mcr_image & MCR_RTS) &&
2149		    !(tp->t_state & TS_TBLOCK))
2150			outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
2151	}
2152#else
2153	if ((com->state & CS_RTS_IFLOW) && !(com->mcr_image & MCR_RTS) &&
2154	    !(tp->t_state & TS_TBLOCK))
2155		outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
2156#endif
2157}
2158
2159static int
2160siointr(arg)
2161	void		*arg;
2162{
2163	struct com_s	*com;
2164#if defined(PC98) && defined(COM_MULTIPORT)
2165	u_char		rsa_buf_status;
2166#endif
2167
2168#ifndef COM_MULTIPORT
2169	com = (struct com_s *)arg;
2170
2171	mtx_lock_spin(&sio_lock);
2172	siointr1(com);
2173	mtx_unlock_spin(&sio_lock);
2174#else /* COM_MULTIPORT */
2175	bool_t		possibly_more_intrs;
2176	int		unit;
2177
2178	/*
2179	 * Loop until there is no activity on any port.  This is necessary
2180	 * to get an interrupt edge more than to avoid another interrupt.
2181	 * If the IRQ signal is just an OR of the IRQ signals from several
2182	 * devices, then the edge from one may be lost because another is
2183	 * on.
2184	 */
2185	mtx_lock_spin(&sio_lock);
2186	do {
2187		possibly_more_intrs = FALSE;
2188		for (unit = 0; unit < sio_numunits; ++unit) {
2189			com = com_addr(unit);
2190			/*
2191			 * XXX COM_LOCK();
2192			 * would it work here, or be counter-productive?
2193			 */
2194#ifdef PC98
2195			if (com != NULL
2196			    && !com->gone
2197			    && IS_8251(com->pc98_if_type)) {
2198				siointr1(com);
2199			} else if (com != NULL
2200			    && !com->gone
2201			    && com->pc98_if_type == COM_IF_RSA98III) {
2202				rsa_buf_status =
2203				    inb(com->rsabase + rsa_srr) & 0xc9;
2204				if ((rsa_buf_status & 0xc8)
2205				    || !(rsa_buf_status & 0x01)) {
2206				    siointr1(com);
2207				    if (rsa_buf_status !=
2208					(inb(com->rsabase + rsa_srr) & 0xc9))
2209					possibly_more_intrs = TRUE;
2210				}
2211			} else
2212#endif
2213			if (com != NULL
2214			    && !com->gone
2215			    && (inb(com->int_id_port) & IIR_IMASK)
2216			       != IIR_NOPEND) {
2217				siointr1(com);
2218				possibly_more_intrs = TRUE;
2219			}
2220			/* XXX COM_UNLOCK(); */
2221		}
2222	} while (possibly_more_intrs);
2223	mtx_unlock_spin(&sio_lock);
2224#endif /* COM_MULTIPORT */
2225	return (FILTER_HANDLED);
2226}
2227
2228static struct timespec siots[8];
2229static int siotso;
2230static int volatile siotsunit = -1;
2231
2232static int
2233sysctl_siots(SYSCTL_HANDLER_ARGS)
2234{
2235	char buf[128];
2236	long long delta;
2237	size_t len;
2238	int error, i, tso;
2239
2240	for (i = 1, tso = siotso; i < tso; i++) {
2241		delta = (long long)(siots[i].tv_sec - siots[i - 1].tv_sec) *
2242		    1000000000 +
2243		    (siots[i].tv_nsec - siots[i - 1].tv_nsec);
2244		len = sprintf(buf, "%lld\n", delta);
2245		if (delta >= 110000)
2246			len += sprintf(buf + len - 1, ": *** %ld.%09ld\n",
2247			    (long)siots[i].tv_sec, siots[i].tv_nsec) - 1;
2248		if (i == tso - 1)
2249			buf[len - 1] = '\0';
2250		error = SYSCTL_OUT(req, buf, len);
2251		if (error != 0)
2252			return (error);
2253		uio_yield();
2254	}
2255	return (0);
2256}
2257
2258SYSCTL_PROC(_machdep, OID_AUTO, siots, CTLTYPE_STRING | CTLFLAG_RD,
2259    0, 0, sysctl_siots, "A", "sio timestamps");
2260
2261static void
2262siointr1(com)
2263	struct com_s	*com;
2264{
2265	u_char	int_ctl;
2266	u_char	int_ctl_new;
2267	u_char	line_status;
2268	u_char	modem_status;
2269	u_char	*ioptr;
2270	u_char	recv_data;
2271#ifdef PC98
2272	u_char	tmp = 0;
2273	u_char	rsa_buf_status = 0;
2274	int	rsa_tx_fifo_size = 0;
2275#endif /* PC98 */
2276#if defined(KDB) && defined(ALT_BREAK_TO_DEBUGGER)
2277	int	kdb_brk;
2278
2279again:
2280#endif
2281
2282	if (COM_IIR_TXRDYBUG(com->flags)) {
2283		int_ctl = inb(com->int_ctl_port);
2284		int_ctl_new = int_ctl;
2285	} else {
2286		int_ctl = 0;
2287		int_ctl_new = 0;
2288	}
2289
2290	while (!com->gone) {
2291#ifdef PC98
2292status_read:;
2293		if (IS_8251(com->pc98_if_type)) {
2294			if (com->pc98_8251fifo_enable)
2295				tmp = inb(I8251F_lsr);
2296			else
2297				tmp = inb(com->sts_port);
2298more_intr:
2299			line_status = 0;
2300			if (com->pc98_8251fifo_enable) {
2301			    if (tmp & FLSR_TxRDY) line_status |= LSR_TXRDY;
2302			    if (tmp & FLSR_RxRDY) line_status |= LSR_RXRDY;
2303			    if (tmp & FLSR_TxEMP) line_status |= LSR_TSRE;
2304			    if (tmp & FLSR_PE)    line_status |= LSR_PE;
2305			    if (tmp & FLSR_OE)    line_status |= LSR_OE;
2306			    if (tmp & FLSR_BI)    line_status |= LSR_BI;
2307			} else {
2308			    if (tmp & STS8251_TxRDY)  line_status |= LSR_TXRDY;
2309			    if (tmp & STS8251_RxRDY)  line_status |= LSR_RXRDY;
2310			    if (tmp & STS8251_TxEMP)  line_status |= LSR_TSRE;
2311			    if (tmp & STS8251_PE)     line_status |= LSR_PE;
2312			    if (tmp & STS8251_OE)     line_status |= LSR_OE;
2313			    if (tmp & STS8251_FE)     line_status |= LSR_FE;
2314			    if (tmp & STS8251_BI)     line_status |= LSR_BI;
2315			}
2316		} else {
2317#endif /* PC98 */
2318		if (com->pps.ppsparam.mode & PPS_CAPTUREBOTH) {
2319			modem_status = inb(com->modem_status_port);
2320		        if ((modem_status ^ com->last_modem_status) &
2321			    com->pps_bit) {
2322				pps_capture(&com->pps);
2323				pps_event(&com->pps,
2324				    (modem_status & com->pps_bit) ?
2325				    PPS_CAPTUREASSERT : PPS_CAPTURECLEAR);
2326			}
2327		}
2328		line_status = inb(com->line_status_port);
2329#ifdef PC98
2330		}
2331		if (com->pc98_if_type == COM_IF_RSA98III)
2332			rsa_buf_status = inb(com->rsabase + rsa_srr);
2333#endif /* PC98 */
2334
2335		/* input event? (check first to help avoid overruns) */
2336#ifndef PC98
2337		while (line_status & LSR_RCV_MASK) {
2338#else
2339		while ((line_status & LSR_RCV_MASK)
2340		       || (com->pc98_if_type == COM_IF_RSA98III
2341			   && (rsa_buf_status & 0x08))) {
2342#endif /* PC98 */
2343			/* break/unnattached error bits or real input? */
2344#ifdef PC98
2345			if (IS_8251(com->pc98_if_type)) {
2346				if (com->pc98_8251fifo_enable) {
2347				    recv_data = inb(I8251F_data);
2348				    if (tmp &
2349					(FLSR_PE | FLSR_OE | FLSR_BI)) {
2350					pc98_i8251_or_cmd(com, CMD8251_ER);
2351					recv_data = 0;
2352				    }
2353				} else {
2354				    recv_data = inb(com->data_port);
2355				    if (tmp & (STS8251_PE | STS8251_OE |
2356					       STS8251_FE | STS8251_BI)) {
2357					pc98_i8251_or_cmd(com, CMD8251_ER);
2358					recv_data = 0;
2359				    }
2360				}
2361			} else if (com->pc98_if_type == COM_IF_RSA98III) {
2362				if (!(rsa_buf_status & 0x08))
2363					recv_data = 0;
2364				else
2365					recv_data = inb(com->data_port);
2366			} else
2367#endif
2368			if (!(line_status & LSR_RXRDY))
2369				recv_data = 0;
2370			else
2371				recv_data = inb(com->data_port);
2372#ifdef KDB
2373#ifdef ALT_BREAK_TO_DEBUGGER
2374			if (com->unit == comconsole &&
2375			    (kdb_brk = kdb_alt_break(recv_data,
2376					&com->alt_brk_state)) != 0) {
2377				mtx_unlock_spin(&sio_lock);
2378				switch (kdb_brk) {
2379				case KDB_REQ_DEBUGGER:
2380					kdb_enter(KDB_WHY_BREAK,
2381					    "Break sequence on console");
2382					break;
2383				case KDB_REQ_PANIC:
2384					kdb_panic("panic on console");
2385					break;
2386				case KDB_REQ_REBOOT:
2387					kdb_reboot();
2388					break;
2389				}
2390				mtx_lock_spin(&sio_lock);
2391				goto again;
2392			}
2393#endif /* ALT_BREAK_TO_DEBUGGER */
2394#endif /* KDB */
2395			if (line_status & (LSR_BI | LSR_FE | LSR_PE)) {
2396				/*
2397				 * Don't store BI if IGNBRK or FE/PE if IGNPAR.
2398				 * Otherwise, push the work to a higher level
2399				 * (to handle PARMRK) if we're bypassing.
2400				 * Otherwise, convert BI/FE and PE+INPCK to 0.
2401				 *
2402				 * This makes bypassing work right in the
2403				 * usual "raw" case (IGNBRK set, and IGNPAR
2404				 * and INPCK clear).
2405				 *
2406				 * Note: BI together with FE/PE means just BI.
2407				 */
2408				if (line_status & LSR_BI) {
2409#if defined(KDB) && defined(BREAK_TO_DEBUGGER)
2410					if (com->unit == comconsole) {
2411						kdb_enter(KDB_WHY_BREAK,
2412						    "Line break on console");
2413						goto cont;
2414					}
2415#endif
2416					if (com->tp == NULL
2417					    || com->tp->t_iflag & IGNBRK)
2418						goto cont;
2419				} else {
2420					if (com->tp == NULL
2421					    || com->tp->t_iflag & IGNPAR)
2422						goto cont;
2423				}
2424				if (com->tp->t_state & TS_CAN_BYPASS_L_RINT
2425				    && (line_status & (LSR_BI | LSR_FE)
2426					|| com->tp->t_iflag & INPCK))
2427					recv_data = 0;
2428			}
2429			++com->bytes_in;
2430			if (com->tp != NULL &&
2431			    com->tp->t_hotchar != 0 && recv_data == com->tp->t_hotchar)
2432				swi_sched(sio_fast_ih, 0);
2433			ioptr = com->iptr;
2434			if (ioptr >= com->ibufend)
2435				CE_RECORD(com, CE_INTERRUPT_BUF_OVERFLOW);
2436			else {
2437				if (com->tp != NULL && com->tp->t_do_timestamp)
2438					microtime(&com->tp->t_timestamp);
2439				++com_events;
2440				swi_sched(sio_slow_ih, SWI_DELAY);
2441#if 0 /* for testing input latency vs efficiency */
2442if (com->iptr - com->ibuf == 8)
2443	swi_sched(sio_fast_ih, 0);
2444#endif
2445				ioptr[0] = recv_data;
2446				ioptr[com->ierroff] = line_status;
2447				com->iptr = ++ioptr;
2448				if (ioptr == com->ihighwater
2449				    && com->state & CS_RTS_IFLOW)
2450#ifdef PC98
2451					IS_8251(com->pc98_if_type) ?
2452						com_tiocm_bic(com, TIOCM_RTS) :
2453#endif
2454					outb(com->modem_ctl_port,
2455					     com->mcr_image &= ~MCR_RTS);
2456				if (line_status & LSR_OE)
2457					CE_RECORD(com, CE_OVERRUN);
2458			}
2459cont:
2460			if (line_status & LSR_TXRDY
2461			    && com->state >= (CS_BUSY | CS_TTGO | CS_ODEVREADY))
2462				goto txrdy;
2463
2464			/*
2465			 * "& 0x7F" is to avoid the gcc-1.40 generating a slow
2466			 * jump from the top of the loop to here
2467			 */
2468#ifdef PC98
2469			if (IS_8251(com->pc98_if_type))
2470				goto status_read;
2471			else
2472#endif
2473			line_status = inb(com->line_status_port) & 0x7F;
2474#ifdef PC98
2475			if (com->pc98_if_type == COM_IF_RSA98III)
2476				rsa_buf_status = inb(com->rsabase + rsa_srr);
2477#endif /* PC98 */
2478		}
2479
2480		/* modem status change? (always check before doing output) */
2481#ifdef PC98
2482		if (!IS_8251(com->pc98_if_type)) {
2483#endif
2484		modem_status = inb(com->modem_status_port);
2485		if (modem_status != com->last_modem_status) {
2486			/*
2487			 * Schedule high level to handle DCD changes.  Note
2488			 * that we don't use the delta bits anywhere.  Some
2489			 * UARTs mess them up, and it's easy to remember the
2490			 * previous bits and calculate the delta.
2491			 */
2492			com->last_modem_status = modem_status;
2493			if (!(com->state & CS_CHECKMSR)) {
2494				com_events += LOTS_OF_EVENTS;
2495				com->state |= CS_CHECKMSR;
2496				swi_sched(sio_fast_ih, 0);
2497			}
2498
2499			/* handle CTS change immediately for crisp flow ctl */
2500			if (com->state & CS_CTS_OFLOW) {
2501				if (modem_status & MSR_CTS)
2502					com->state |= CS_ODEVREADY;
2503				else
2504					com->state &= ~CS_ODEVREADY;
2505			}
2506		}
2507#ifdef PC98
2508		}
2509#endif
2510
2511txrdy:
2512		/* output queued and everything ready? */
2513#ifndef PC98
2514		if (line_status & LSR_TXRDY
2515		    && com->state >= (CS_BUSY | CS_TTGO | CS_ODEVREADY)) {
2516#else
2517		if (((com->pc98_if_type == COM_IF_RSA98III)
2518		     ? (rsa_buf_status & 0x02)
2519		     : (line_status & LSR_TXRDY))
2520		    && com->state >= (CS_BUSY | CS_TTGO | CS_ODEVREADY)) {
2521#endif
2522#ifdef PC98
2523			Port_t	tmp_data_port;
2524
2525			if (IS_8251(com->pc98_if_type) &&
2526			    com->pc98_8251fifo_enable)
2527				tmp_data_port = I8251F_data;
2528			else
2529				tmp_data_port = com->data_port;
2530#endif
2531
2532			ioptr = com->obufq.l_head;
2533			if (com->tx_fifo_size > 1 && com->unit != siotsunit) {
2534				u_int	ocount;
2535
2536				ocount = com->obufq.l_tail - ioptr;
2537#ifdef PC98
2538				if (com->pc98_if_type == COM_IF_RSA98III) {
2539				  rsa_buf_status = inb(com->rsabase + rsa_srr);
2540				  rsa_tx_fifo_size = 1024;
2541				  if (!(rsa_buf_status & 0x01))
2542				      rsa_tx_fifo_size = 2048;
2543				  if (ocount > rsa_tx_fifo_size)
2544				      ocount = rsa_tx_fifo_size;
2545				} else
2546#endif
2547				if (ocount > com->tx_fifo_size)
2548					ocount = com->tx_fifo_size;
2549				com->bytes_out += ocount;
2550				do
2551#ifdef PC98
2552					outb(tmp_data_port, *ioptr++);
2553#else
2554					outb(com->data_port, *ioptr++);
2555#endif
2556				while (--ocount != 0);
2557			} else {
2558#ifdef PC98
2559				outb(tmp_data_port, *ioptr++);
2560#else
2561				outb(com->data_port, *ioptr++);
2562#endif
2563				++com->bytes_out;
2564				if (com->unit == siotsunit
2565				    && siotso < sizeof siots / sizeof siots[0])
2566					nanouptime(&siots[siotso++]);
2567			}
2568#ifdef PC98
2569			if (IS_8251(com->pc98_if_type))
2570			    if (!(pc98_check_i8251_interrupt(com) & IEN_TxFLAG))
2571				com_int_Tx_enable(com);
2572#endif
2573			com->obufq.l_head = ioptr;
2574			if (COM_IIR_TXRDYBUG(com->flags))
2575				int_ctl_new = int_ctl | IER_ETXRDY;
2576			if (ioptr >= com->obufq.l_tail) {
2577				struct lbq	*qp;
2578
2579				qp = com->obufq.l_next;
2580				qp->l_queued = FALSE;
2581				qp = qp->l_next;
2582				if (qp != NULL) {
2583					com->obufq.l_head = qp->l_head;
2584					com->obufq.l_tail = qp->l_tail;
2585					com->obufq.l_next = qp;
2586				} else {
2587					/* output just completed */
2588					if (COM_IIR_TXRDYBUG(com->flags))
2589						int_ctl_new = int_ctl
2590							      & ~IER_ETXRDY;
2591					com->state &= ~CS_BUSY;
2592#if defined(PC98)
2593					if (IS_8251(com->pc98_if_type) &&
2594					    pc98_check_i8251_interrupt(com) & IEN_TxFLAG)
2595						com_int_Tx_disable(com);
2596#endif
2597				}
2598				if (!(com->state & CS_ODONE)) {
2599					com_events += LOTS_OF_EVENTS;
2600					com->state |= CS_ODONE;
2601					/* handle at high level ASAP */
2602					swi_sched(sio_fast_ih, 0);
2603				}
2604			}
2605#ifdef PC98
2606			if (COM_IIR_TXRDYBUG(com->flags)
2607			    && int_ctl != int_ctl_new) {
2608				if (com->pc98_if_type == COM_IF_RSA98III) {
2609				    int_ctl_new &= ~(IER_ETXRDY | IER_ERXRDY);
2610				    outb(com->int_ctl_port, int_ctl_new);
2611				    outb(com->rsabase + rsa_ier, 0x1d);
2612				} else
2613				    outb(com->int_ctl_port, int_ctl_new);
2614			}
2615#else
2616			if (COM_IIR_TXRDYBUG(com->flags)
2617			    && int_ctl != int_ctl_new)
2618				outb(com->int_ctl_port, int_ctl_new);
2619#endif
2620		}
2621#ifdef PC98
2622		else if (line_status & LSR_TXRDY) {
2623		    if (IS_8251(com->pc98_if_type))
2624			if (pc98_check_i8251_interrupt(com) & IEN_TxFLAG)
2625			    com_int_Tx_disable(com);
2626		}
2627		if (IS_8251(com->pc98_if_type)) {
2628		    if (com->pc98_8251fifo_enable) {
2629			if ((tmp = inb(I8251F_lsr)) & FLSR_RxRDY)
2630			    goto more_intr;
2631		    } else {
2632			if ((tmp = inb(com->sts_port)) & STS8251_RxRDY)
2633			    goto more_intr;
2634		    }
2635		}
2636#endif
2637
2638		/* finished? */
2639#ifndef COM_MULTIPORT
2640#ifdef PC98
2641		if (IS_8251(com->pc98_if_type))
2642			return;
2643#endif
2644		if ((inb(com->int_id_port) & IIR_IMASK) == IIR_NOPEND)
2645#endif /* COM_MULTIPORT */
2646			return;
2647	}
2648}
2649
2650/* software interrupt handler for SWI_TTY */
2651static void
2652siopoll(void *dummy)
2653{
2654	int		unit;
2655
2656	if (com_events == 0)
2657		return;
2658repeat:
2659	for (unit = 0; unit < sio_numunits; ++unit) {
2660		struct com_s	*com;
2661		int		incc;
2662		struct tty	*tp;
2663
2664		com = com_addr(unit);
2665		if (com == NULL)
2666			continue;
2667		tp = com->tp;
2668		if (tp == NULL || com->gone) {
2669			/*
2670			 * Discard any events related to never-opened or
2671			 * going-away devices.
2672			 */
2673			mtx_lock_spin(&sio_lock);
2674			incc = com->iptr - com->ibuf;
2675			com->iptr = com->ibuf;
2676			if (com->state & CS_CHECKMSR) {
2677				incc += LOTS_OF_EVENTS;
2678				com->state &= ~CS_CHECKMSR;
2679			}
2680			com_events -= incc;
2681			mtx_unlock_spin(&sio_lock);
2682			continue;
2683		}
2684		if (com->iptr != com->ibuf) {
2685			mtx_lock_spin(&sio_lock);
2686			sioinput(com);
2687			mtx_unlock_spin(&sio_lock);
2688		}
2689		if (com->state & CS_CHECKMSR) {
2690			u_char	delta_modem_status;
2691
2692#ifdef PC98
2693			if (!IS_8251(com->pc98_if_type)) {
2694#endif
2695			mtx_lock_spin(&sio_lock);
2696			delta_modem_status = com->last_modem_status
2697					     ^ com->prev_modem_status;
2698			com->prev_modem_status = com->last_modem_status;
2699			com_events -= LOTS_OF_EVENTS;
2700			com->state &= ~CS_CHECKMSR;
2701			mtx_unlock_spin(&sio_lock);
2702			if (delta_modem_status & MSR_DCD)
2703				ttyld_modem(tp,
2704				    com->prev_modem_status & MSR_DCD);
2705#ifdef PC98
2706			}
2707#endif
2708		}
2709		if (com->state & CS_ODONE) {
2710			mtx_lock_spin(&sio_lock);
2711			com_events -= LOTS_OF_EVENTS;
2712			com->state &= ~CS_ODONE;
2713			mtx_unlock_spin(&sio_lock);
2714			if (!(com->state & CS_BUSY)
2715			    && !(com->extra_state & CSE_BUSYCHECK)) {
2716				timeout(siobusycheck, com, hz / 100);
2717				com->extra_state |= CSE_BUSYCHECK;
2718			}
2719			ttyld_start(tp);
2720		}
2721		if (com_events == 0)
2722			break;
2723	}
2724	if (com_events >= LOTS_OF_EVENTS)
2725		goto repeat;
2726}
2727
2728static void
2729combreak(tp, sig)
2730	struct tty 	*tp;
2731	int		sig;
2732{
2733	struct com_s	*com;
2734
2735	com = tp->t_sc;
2736
2737#ifdef PC98
2738	if (sig)
2739		com_send_break_on(com);
2740	else
2741		com_send_break_off(com);
2742#else
2743	if (sig)
2744		sio_setreg(com, com_cfcr, com->cfcr_image |= CFCR_SBREAK);
2745	else
2746		sio_setreg(com, com_cfcr, com->cfcr_image &= ~CFCR_SBREAK);
2747#endif
2748}
2749
2750static int
2751comparam(tp, t)
2752	struct tty	*tp;
2753	struct termios	*t;
2754{
2755	u_int		cfcr;
2756	int		cflag;
2757	struct com_s	*com;
2758	u_int		divisor;
2759	u_char		dlbh;
2760	u_char		dlbl;
2761	u_char		efr_flowbits;
2762	int		s;
2763#ifdef PC98
2764	u_char		param = 0;
2765#endif
2766
2767	com = tp->t_sc;
2768	if (com == NULL)
2769		return (ENODEV);
2770
2771#ifdef PC98
2772	cfcr = 0;
2773
2774	if (IS_8251(com->pc98_if_type)) {
2775		if (pc98_ttspeedtab(com, t->c_ospeed, &divisor) != 0)
2776			return (EINVAL);
2777	} else {
2778#endif
2779	/* check requested parameters */
2780	if (t->c_ispeed != (t->c_ospeed != 0 ? t->c_ospeed : tp->t_ospeed))
2781		return (EINVAL);
2782	divisor = siodivisor(com->rclk, t->c_ispeed);
2783	if (divisor == 0)
2784		return (EINVAL);
2785#ifdef PC98
2786	}
2787#endif
2788
2789	/* parameters are OK, convert them to the com struct and the device */
2790	s = spltty();
2791#ifdef PC98
2792	if (IS_8251(com->pc98_if_type)) {
2793		if (t->c_ospeed == 0)
2794			com_tiocm_bic(com, TIOCM_DTR|TIOCM_RTS|TIOCM_LE);
2795		else
2796			com_tiocm_bis(com, TIOCM_DTR|TIOCM_RTS|TIOCM_LE);
2797	} else
2798#endif
2799	if (t->c_ospeed == 0)
2800		(void)commodem(tp, 0, SER_DTR);	/* hang up line */
2801	else
2802		(void)commodem(tp, SER_DTR, 0);
2803	cflag = t->c_cflag;
2804#ifdef PC98
2805	if (!IS_8251(com->pc98_if_type)) {
2806#endif
2807	switch (cflag & CSIZE) {
2808	case CS5:
2809		cfcr = CFCR_5BITS;
2810		break;
2811	case CS6:
2812		cfcr = CFCR_6BITS;
2813		break;
2814	case CS7:
2815		cfcr = CFCR_7BITS;
2816		break;
2817	default:
2818		cfcr = CFCR_8BITS;
2819		break;
2820	}
2821	if (cflag & PARENB) {
2822		cfcr |= CFCR_PENAB;
2823		if (!(cflag & PARODD))
2824			cfcr |= CFCR_PEVEN;
2825	}
2826	if (cflag & CSTOPB)
2827		cfcr |= CFCR_STOPB;
2828
2829	if (com->hasfifo) {
2830		/*
2831		 * Use a fifo trigger level low enough so that the input
2832		 * latency from the fifo is less than about 16 msec and
2833		 * the total latency is less than about 30 msec.  These
2834		 * latencies are reasonable for humans.  Serial comms
2835		 * protocols shouldn't expect anything better since modem
2836		 * latencies are larger.
2837		 *
2838		 * The fifo trigger level cannot be set at RX_HIGH for high
2839		 * speed connections without further work on reducing
2840		 * interrupt disablement times in other parts of the system,
2841		 * without producing silo overflow errors.
2842		 */
2843		com->fifo_image = com->unit == siotsunit ? 0
2844				  : t->c_ispeed <= 4800
2845				  ? FIFO_ENABLE : FIFO_ENABLE | FIFO_RX_MEDH;
2846#ifdef COM_ESP
2847		/*
2848		 * The Hayes ESP card needs the fifo DMA mode bit set
2849		 * in compatibility mode.  If not, it will interrupt
2850		 * for each character received.
2851		 */
2852		if (com->esp)
2853			com->fifo_image |= FIFO_DMA_MODE;
2854#endif
2855		sio_setreg(com, com_fifo, com->fifo_image);
2856	}
2857#ifdef PC98
2858	}
2859#endif
2860
2861	/*
2862	 * This returns with interrupts disabled so that we can complete
2863	 * the speed change atomically.  Keeping interrupts disabled is
2864	 * especially important while com_data is hidden.
2865	 */
2866	(void) siosetwater(com, t->c_ispeed);
2867
2868#ifdef PC98
2869	if (IS_8251(com->pc98_if_type))
2870		com_cflag_and_speed_set(com, cflag, t->c_ospeed);
2871	else {
2872#endif
2873	sio_setreg(com, com_cfcr, cfcr | CFCR_DLAB);
2874	/*
2875	 * Only set the divisor registers if they would change, since on
2876	 * some 16550 incompatibles (UMC8669F), setting them while input
2877	 * is arriving loses sync until data stops arriving.
2878	 */
2879	dlbl = divisor & 0xFF;
2880	if (sio_getreg(com, com_dlbl) != dlbl)
2881		sio_setreg(com, com_dlbl, dlbl);
2882	dlbh = divisor >> 8;
2883	if (sio_getreg(com, com_dlbh) != dlbh)
2884		sio_setreg(com, com_dlbh, dlbh);
2885#ifdef PC98
2886	}
2887#endif
2888
2889	efr_flowbits = 0;
2890
2891	if (cflag & CRTS_IFLOW) {
2892		com->state |= CS_RTS_IFLOW;
2893		efr_flowbits |= EFR_AUTORTS;
2894		/*
2895		 * If CS_RTS_IFLOW just changed from off to on, the change
2896		 * needs to be propagated to MCR_RTS.  This isn't urgent,
2897		 * so do it later by calling comstart() instead of repeating
2898		 * a lot of code from comstart() here.
2899		 */
2900	} else if (com->state & CS_RTS_IFLOW) {
2901		com->state &= ~CS_RTS_IFLOW;
2902		/*
2903		 * CS_RTS_IFLOW just changed from on to off.  Force MCR_RTS
2904		 * on here, since comstart() won't do it later.
2905		 */
2906#ifdef PC98
2907		if (IS_8251(com->pc98_if_type))
2908			com_tiocm_bis(com, TIOCM_RTS);
2909		else
2910			outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
2911#else
2912		outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
2913#endif
2914	}
2915
2916	/*
2917	 * Set up state to handle output flow control.
2918	 * XXX - worth handling MDMBUF (DCD) flow control at the lowest level?
2919	 * Now has 10+ msec latency, while CTS flow has 50- usec latency.
2920	 */
2921	com->state |= CS_ODEVREADY;
2922	com->state &= ~CS_CTS_OFLOW;
2923#ifdef PC98
2924	if (com->pc98_if_type == COM_IF_RSA98III) {
2925		param = inb(com->rsabase + rsa_msr);
2926		outb(com->rsabase + rsa_msr, param & 0x14);
2927	}
2928#endif
2929	if (cflag & CCTS_OFLOW) {
2930		com->state |= CS_CTS_OFLOW;
2931		efr_flowbits |= EFR_AUTOCTS;
2932#ifdef PC98
2933		if (IS_8251(com->pc98_if_type)) {
2934			if (!(pc98_get_modem_status(com) & TIOCM_CTS))
2935				com->state &= ~CS_ODEVREADY;
2936		} else if (com->pc98_if_type == COM_IF_RSA98III) {
2937			/* Set automatic flow control mode */
2938			outb(com->rsabase + rsa_msr, param | 0x08);
2939		} else
2940#endif
2941		if (!(com->last_modem_status & MSR_CTS))
2942			com->state &= ~CS_ODEVREADY;
2943	}
2944
2945#ifdef PC98
2946	if (!IS_8251(com->pc98_if_type))
2947		sio_setreg(com, com_cfcr, com->cfcr_image = cfcr);
2948#else
2949	if (com->st16650a) {
2950		sio_setreg(com, com_lcr, LCR_EFR_ENABLE);
2951		sio_setreg(com, com_efr,
2952			   (sio_getreg(com, com_efr)
2953			    & ~(EFR_AUTOCTS | EFR_AUTORTS)) | efr_flowbits);
2954	}
2955	sio_setreg(com, com_cfcr, com->cfcr_image = cfcr);
2956#endif
2957
2958	/* XXX shouldn't call functions while intrs are disabled. */
2959	ttyldoptim(tp);
2960
2961	mtx_unlock_spin(&sio_lock);
2962	splx(s);
2963	comstart(tp);
2964	if (com->ibufold != NULL) {
2965		free(com->ibufold, M_DEVBUF);
2966		com->ibufold = NULL;
2967	}
2968	return (0);
2969}
2970
2971/*
2972 * This function must be called with the sio_lock mutex released and will
2973 * return with it obtained.
2974 */
2975static int
2976siosetwater(com, speed)
2977	struct com_s	*com;
2978	speed_t		speed;
2979{
2980	int		cp4ticks;
2981	u_char		*ibuf;
2982	int		ibufsize;
2983	struct tty	*tp;
2984
2985	/*
2986	 * Make the buffer size large enough to handle a softtty interrupt
2987	 * latency of about 2 ticks without loss of throughput or data
2988	 * (about 3 ticks if input flow control is not used or not honoured,
2989	 * but a bit less for CS5-CS7 modes).
2990	 */
2991	cp4ticks = speed / 10 / hz * 4;
2992	for (ibufsize = 128; ibufsize < cp4ticks;)
2993		ibufsize <<= 1;
2994#ifdef PC98
2995	if (com->pc98_if_type == COM_IF_RSA98III)
2996		ibufsize = 2048;
2997#endif
2998	if (ibufsize == com->ibufsize) {
2999		mtx_lock_spin(&sio_lock);
3000		return (0);
3001	}
3002
3003	/*
3004	 * Allocate input buffer.  The extra factor of 2 in the size is
3005	 * to allow for an error byte for each input byte.
3006	 */
3007	ibuf = malloc(2 * ibufsize, M_DEVBUF, M_NOWAIT);
3008	if (ibuf == NULL) {
3009		mtx_lock_spin(&sio_lock);
3010		return (ENOMEM);
3011	}
3012
3013	/* Initialize non-critical variables. */
3014	com->ibufold = com->ibuf;
3015	com->ibufsize = ibufsize;
3016	tp = com->tp;
3017	if (tp != NULL) {
3018		tp->t_ififosize = 2 * ibufsize;
3019		tp->t_ispeedwat = (speed_t)-1;
3020		tp->t_ospeedwat = (speed_t)-1;
3021	}
3022
3023	/*
3024	 * Read current input buffer, if any.  Continue with interrupts
3025	 * disabled.
3026	 */
3027	mtx_lock_spin(&sio_lock);
3028	if (com->iptr != com->ibuf)
3029		sioinput(com);
3030
3031	/*-
3032	 * Initialize critical variables, including input buffer watermarks.
3033	 * The external device is asked to stop sending when the buffer
3034	 * exactly reaches high water, or when the high level requests it.
3035	 * The high level is notified immediately (rather than at a later
3036	 * clock tick) when this watermark is reached.
3037	 * The buffer size is chosen so the watermark should almost never
3038	 * be reached.
3039	 * The low watermark is invisibly 0 since the buffer is always
3040	 * emptied all at once.
3041	 */
3042	com->iptr = com->ibuf = ibuf;
3043	com->ibufend = ibuf + ibufsize;
3044	com->ierroff = ibufsize;
3045	com->ihighwater = ibuf + 3 * ibufsize / 4;
3046	return (0);
3047}
3048
3049static void
3050comstart(tp)
3051	struct tty	*tp;
3052{
3053	struct com_s	*com;
3054	int		s;
3055
3056	com = tp->t_sc;
3057	if (com == NULL)
3058		return;
3059	s = spltty();
3060	mtx_lock_spin(&sio_lock);
3061	if (tp->t_state & TS_TTSTOP)
3062		com->state &= ~CS_TTGO;
3063	else
3064		com->state |= CS_TTGO;
3065	if (tp->t_state & TS_TBLOCK) {
3066#ifdef PC98
3067		if (IS_8251(com->pc98_if_type)) {
3068		    if ((com_tiocm_get(com) & TIOCM_RTS) &&
3069			(com->state & CS_RTS_IFLOW))
3070			com_tiocm_bic(com, TIOCM_RTS);
3071		} else {
3072		    if ((com->mcr_image & MCR_RTS) &&
3073			(com->state & CS_RTS_IFLOW))
3074			outb(com->modem_ctl_port, com->mcr_image &= ~MCR_RTS);
3075		}
3076#else
3077		if (com->mcr_image & MCR_RTS && com->state & CS_RTS_IFLOW)
3078			outb(com->modem_ctl_port, com->mcr_image &= ~MCR_RTS);
3079#endif
3080	} else {
3081#ifdef PC98
3082		if (IS_8251(com->pc98_if_type)) {
3083		    if (!(com_tiocm_get(com) & TIOCM_RTS) &&
3084			com->iptr < com->ihighwater &&
3085			com->state & CS_RTS_IFLOW)
3086			com_tiocm_bis(com, TIOCM_RTS);
3087		} else {
3088		    if (!(com->mcr_image & MCR_RTS) &&
3089			com->iptr < com->ihighwater &&
3090			com->state & CS_RTS_IFLOW)
3091			outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
3092		}
3093#else
3094		if (!(com->mcr_image & MCR_RTS) && com->iptr < com->ihighwater
3095		    && com->state & CS_RTS_IFLOW)
3096			outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
3097#endif
3098	}
3099	mtx_unlock_spin(&sio_lock);
3100	if (tp->t_state & (TS_TIMEOUT | TS_TTSTOP)) {
3101		ttwwakeup(tp);
3102		splx(s);
3103		return;
3104	}
3105	if (tp->t_outq.c_cc != 0) {
3106		struct lbq	*qp;
3107		struct lbq	*next;
3108
3109		if (!com->obufs[0].l_queued) {
3110			com->obufs[0].l_tail
3111			    = com->obuf1 + q_to_b(&tp->t_outq, com->obuf1,
3112#ifdef PC98
3113						  com->obufsize);
3114#else
3115						  sizeof com->obuf1);
3116#endif
3117			com->obufs[0].l_next = NULL;
3118			com->obufs[0].l_queued = TRUE;
3119			mtx_lock_spin(&sio_lock);
3120			if (com->state & CS_BUSY) {
3121				qp = com->obufq.l_next;
3122				while ((next = qp->l_next) != NULL)
3123					qp = next;
3124				qp->l_next = &com->obufs[0];
3125			} else {
3126				com->obufq.l_head = com->obufs[0].l_head;
3127				com->obufq.l_tail = com->obufs[0].l_tail;
3128				com->obufq.l_next = &com->obufs[0];
3129				com->state |= CS_BUSY;
3130			}
3131			mtx_unlock_spin(&sio_lock);
3132		}
3133		if (tp->t_outq.c_cc != 0 && !com->obufs[1].l_queued) {
3134			com->obufs[1].l_tail
3135			    = com->obuf2 + q_to_b(&tp->t_outq, com->obuf2,
3136#ifdef PC98
3137						  com->obufsize);
3138#else
3139						  sizeof com->obuf2);
3140#endif
3141			com->obufs[1].l_next = NULL;
3142			com->obufs[1].l_queued = TRUE;
3143			mtx_lock_spin(&sio_lock);
3144			if (com->state & CS_BUSY) {
3145				qp = com->obufq.l_next;
3146				while ((next = qp->l_next) != NULL)
3147					qp = next;
3148				qp->l_next = &com->obufs[1];
3149			} else {
3150				com->obufq.l_head = com->obufs[1].l_head;
3151				com->obufq.l_tail = com->obufs[1].l_tail;
3152				com->obufq.l_next = &com->obufs[1];
3153				com->state |= CS_BUSY;
3154			}
3155			mtx_unlock_spin(&sio_lock);
3156		}
3157		tp->t_state |= TS_BUSY;
3158	}
3159	mtx_lock_spin(&sio_lock);
3160	if (com->state >= (CS_BUSY | CS_TTGO))
3161		siointr1(com);	/* fake interrupt to start output */
3162	mtx_unlock_spin(&sio_lock);
3163	ttwwakeup(tp);
3164	splx(s);
3165}
3166
3167static void
3168comstop(tp, rw)
3169	struct tty	*tp;
3170	int		rw;
3171{
3172	struct com_s	*com;
3173#ifdef PC98
3174	int		rsa98_tmp  = 0;
3175#endif
3176
3177	com = tp->t_sc;
3178	if (com == NULL || com->gone)
3179		return;
3180	mtx_lock_spin(&sio_lock);
3181	if (rw & FWRITE) {
3182#ifdef PC98
3183		if (!IS_8251(com->pc98_if_type)) {
3184#endif
3185		if (com->hasfifo)
3186#ifdef COM_ESP
3187		    /* XXX avoid h/w bug. */
3188		    if (!com->esp)
3189#endif
3190			sio_setreg(com, com_fifo,
3191				   FIFO_XMT_RST | com->fifo_image);
3192#ifdef PC98
3193		if (com->pc98_if_type == COM_IF_RSA98III)
3194		    for (rsa98_tmp = 0; rsa98_tmp < 2048; rsa98_tmp++)
3195			sio_setreg(com, com_fifo,
3196				   FIFO_XMT_RST | com->fifo_image);
3197		}
3198#endif
3199		com->obufs[0].l_queued = FALSE;
3200		com->obufs[1].l_queued = FALSE;
3201		if (com->state & CS_ODONE)
3202			com_events -= LOTS_OF_EVENTS;
3203		com->state &= ~(CS_ODONE | CS_BUSY);
3204		com->tp->t_state &= ~TS_BUSY;
3205	}
3206	if (rw & FREAD) {
3207#ifdef PC98
3208		if (!IS_8251(com->pc98_if_type)) {
3209		    if (com->pc98_if_type == COM_IF_RSA98III)
3210			for (rsa98_tmp = 0; rsa98_tmp < 2048; rsa98_tmp++)
3211			    sio_getreg(com, com_data);
3212#endif
3213		if (com->hasfifo)
3214#ifdef COM_ESP
3215		    /* XXX avoid h/w bug. */
3216		    if (!com->esp)
3217#endif
3218			sio_setreg(com, com_fifo,
3219				   FIFO_RCV_RST | com->fifo_image);
3220#ifdef PC98
3221		}
3222#endif
3223		com_events -= (com->iptr - com->ibuf);
3224		com->iptr = com->ibuf;
3225	}
3226	mtx_unlock_spin(&sio_lock);
3227	comstart(tp);
3228}
3229
3230static int
3231commodem(struct tty *tp, int sigon, int sigoff)
3232{
3233	struct com_s	*com;
3234	int	bitand, bitor, msr;
3235#ifdef PC98
3236	int	clr, set;
3237#endif
3238
3239	com = tp->t_sc;
3240	if (com->gone)
3241		return(0);
3242	if (sigon != 0 || sigoff != 0) {
3243#ifdef PC98
3244		if (IS_8251(com->pc98_if_type)) {
3245			bitand = bitor = 0;
3246			clr = set = 0;
3247			if (sigoff & SER_DTR) {
3248				bitand |= TIOCM_DTR;
3249				clr |= CMD8251_DTR;
3250			}
3251			if (sigoff & SER_RTS) {
3252				bitand |= TIOCM_RTS;
3253				clr |= CMD8251_RxEN | CMD8251_RTS;
3254			}
3255			if (sigon & SER_DTR) {
3256				bitor |= TIOCM_DTR;
3257				set |= CMD8251_TxEN | CMD8251_RxEN |
3258					CMD8251_DTR;
3259			}
3260			if (sigon & SER_RTS) {
3261				bitor |= TIOCM_RTS;
3262				set |= CMD8251_TxEN | CMD8251_RxEN |
3263					CMD8251_RTS;
3264			}
3265			bitand = ~bitand;
3266			mtx_lock_spin(&sio_lock);
3267			com->pc98_prev_modem_status &= bitand;
3268			com->pc98_prev_modem_status |= bitor;
3269			pc98_i8251_clear_or_cmd(com, clr, set);
3270			mtx_unlock_spin(&sio_lock);
3271			return (0);
3272		} else {
3273#endif
3274		bitand = bitor = 0;
3275		if (sigoff & SER_DTR)
3276			bitand |= MCR_DTR;
3277		if (sigoff & SER_RTS)
3278			bitand |= MCR_RTS;
3279		if (sigon & SER_DTR)
3280			bitor |= MCR_DTR;
3281		if (sigon & SER_RTS)
3282			bitor |= MCR_RTS;
3283		bitand = ~bitand;
3284		mtx_lock_spin(&sio_lock);
3285		com->mcr_image &= bitand;
3286		com->mcr_image |= bitor;
3287		outb(com->modem_ctl_port, com->mcr_image);
3288		mtx_unlock_spin(&sio_lock);
3289		return (0);
3290#ifdef PC98
3291		}
3292#endif
3293	} else {
3294#ifdef PC98
3295		if (IS_8251(com->pc98_if_type))
3296			return (com_tiocm_get(com));
3297		else {
3298#endif
3299		bitor = 0;
3300		if (com->mcr_image & MCR_DTR)
3301			bitor |= SER_DTR;
3302		if (com->mcr_image & MCR_RTS)
3303			bitor |= SER_RTS;
3304		msr = com->prev_modem_status;
3305		if (msr & MSR_CTS)
3306			bitor |= SER_CTS;
3307		if (msr & MSR_DCD)
3308			bitor |= SER_DCD;
3309		if (msr & MSR_DSR)
3310			bitor |= SER_DSR;
3311		if (msr & MSR_DSR)
3312			bitor |= SER_DSR;
3313		if (msr & (MSR_RI | MSR_TERI))
3314			bitor |= SER_RI;
3315		return (bitor);
3316#ifdef PC98
3317		}
3318#endif
3319	}
3320}
3321
3322static void
3323siosettimeout()
3324{
3325	struct com_s	*com;
3326	bool_t		someopen;
3327	int		unit;
3328
3329	/*
3330	 * Set our timeout period to 1 second if no polled devices are open.
3331	 * Otherwise set it to max(1/200, 1/hz).
3332	 * Enable timeouts iff some device is open.
3333	 */
3334	untimeout(comwakeup, (void *)NULL, sio_timeout_handle);
3335	sio_timeout = hz;
3336	someopen = FALSE;
3337	for (unit = 0; unit < sio_numunits; ++unit) {
3338		com = com_addr(unit);
3339		if (com != NULL && com->tp != NULL
3340		    && com->tp->t_state & TS_ISOPEN && !com->gone) {
3341			someopen = TRUE;
3342			if (com->poll || com->poll_output) {
3343				sio_timeout = hz > 200 ? hz / 200 : 1;
3344				break;
3345			}
3346		}
3347	}
3348	if (someopen) {
3349		sio_timeouts_until_log = hz / sio_timeout;
3350		sio_timeout_handle = timeout(comwakeup, (void *)NULL,
3351					     sio_timeout);
3352	} else {
3353		/* Flush error messages, if any. */
3354		sio_timeouts_until_log = 1;
3355		comwakeup((void *)NULL);
3356		untimeout(comwakeup, (void *)NULL, sio_timeout_handle);
3357	}
3358}
3359
3360static void
3361comwakeup(chan)
3362	void	*chan;
3363{
3364	struct com_s	*com;
3365	int		unit;
3366
3367	sio_timeout_handle = timeout(comwakeup, (void *)NULL, sio_timeout);
3368
3369	/*
3370	 * Recover from lost output interrupts.
3371	 * Poll any lines that don't use interrupts.
3372	 */
3373	for (unit = 0; unit < sio_numunits; ++unit) {
3374		com = com_addr(unit);
3375		if (com != NULL && !com->gone
3376		    && (com->state >= (CS_BUSY | CS_TTGO) || com->poll)) {
3377			mtx_lock_spin(&sio_lock);
3378			siointr1(com);
3379			mtx_unlock_spin(&sio_lock);
3380		}
3381	}
3382
3383	/*
3384	 * Check for and log errors, but not too often.
3385	 */
3386	if (--sio_timeouts_until_log > 0)
3387		return;
3388	sio_timeouts_until_log = hz / sio_timeout;
3389	for (unit = 0; unit < sio_numunits; ++unit) {
3390		int	errnum;
3391
3392		com = com_addr(unit);
3393		if (com == NULL)
3394			continue;
3395		if (com->gone)
3396			continue;
3397		for (errnum = 0; errnum < CE_NTYPES; ++errnum) {
3398			u_int	delta;
3399			u_long	total;
3400
3401			mtx_lock_spin(&sio_lock);
3402			delta = com->delta_error_counts[errnum];
3403			com->delta_error_counts[errnum] = 0;
3404			mtx_unlock_spin(&sio_lock);
3405			if (delta == 0)
3406				continue;
3407			total = com->error_counts[errnum] += delta;
3408			log(LOG_ERR, "sio%d: %u more %s%s (total %lu)\n",
3409			    unit, delta, error_desc[errnum],
3410			    delta == 1 ? "" : "s", total);
3411		}
3412	}
3413}
3414
3415#ifdef PC98
3416/* commint is called when modem control line changes */
3417static void
3418commint(struct cdev *dev)
3419{
3420	register struct tty *tp;
3421	int	stat,delta;
3422	struct com_s *com;
3423
3424	com = dev->si_drv1;
3425	tp = com->tp;
3426
3427	stat = com_tiocm_get(com);
3428	delta = com_tiocm_get_delta(com);
3429
3430	if (com->state & CS_CTS_OFLOW) {
3431		if (stat & TIOCM_CTS)
3432			com->state |= CS_ODEVREADY;
3433		else
3434			com->state &= ~CS_ODEVREADY;
3435	}
3436	if ((delta & TIOCM_CAR) && (ISCALLOUT(dev)) == 0) {
3437	    if (stat & TIOCM_CAR )
3438		(void)ttyld_modem(tp, 1);
3439	    else if (ttyld_modem(tp, 0) == 0) {
3440		/* negate DTR, RTS */
3441		com_tiocm_bic(com, (tp->t_cflag & HUPCL) ?
3442				TIOCM_DTR|TIOCM_RTS|TIOCM_LE : TIOCM_LE );
3443		/* disable IENABLE */
3444		com_int_TxRx_disable( com );
3445	    }
3446	}
3447}
3448#endif
3449
3450/*
3451 * Following are all routines needed for SIO to act as console
3452 */
3453struct siocnstate {
3454	u_char	dlbl;
3455	u_char	dlbh;
3456	u_char	ier;
3457	u_char	cfcr;
3458	u_char	mcr;
3459};
3460
3461/*
3462 * This is a function in order to not replicate "ttyd%d" more
3463 * places than absolutely necessary.
3464 */
3465static void
3466siocnset(struct consdev *cd, int unit)
3467{
3468
3469	cd->cn_unit = unit;
3470	sprintf(cd->cn_name, "ttyd%d", unit);
3471}
3472
3473static speed_t siocngetspeed(Port_t, u_long rclk);
3474static void siocnclose(struct siocnstate *sp, Port_t iobase);
3475static void siocnopen(struct siocnstate *sp, Port_t iobase, int speed);
3476static void siocntxwait(Port_t iobase);
3477
3478static cn_probe_t sio_cnprobe;
3479static cn_init_t sio_cninit;
3480static cn_term_t sio_cnterm;
3481static cn_getc_t sio_cngetc;
3482static cn_putc_t sio_cnputc;
3483
3484CONSOLE_DRIVER(sio);
3485
3486static void
3487siocntxwait(iobase)
3488	Port_t	iobase;
3489{
3490	int	timo;
3491
3492	/*
3493	 * Wait for any pending transmission to finish.  Required to avoid
3494	 * the UART lockup bug when the speed is changed, and for normal
3495	 * transmits.
3496	 */
3497	timo = 100000;
3498	while ((inb(iobase + com_lsr) & (LSR_TSRE | LSR_TXRDY))
3499	       != (LSR_TSRE | LSR_TXRDY) && --timo != 0)
3500		;
3501}
3502
3503/*
3504 * Read the serial port specified and try to figure out what speed
3505 * it's currently running at.  We're assuming the serial port has
3506 * been initialized and is basicly idle.  This routine is only intended
3507 * to be run at system startup.
3508 *
3509 * If the value read from the serial port doesn't make sense, return 0.
3510 */
3511
3512static speed_t
3513siocngetspeed(iobase, rclk)
3514	Port_t	iobase;
3515	u_long	rclk;
3516{
3517	u_int	divisor;
3518	u_char	dlbh;
3519	u_char	dlbl;
3520	u_char  cfcr;
3521
3522	cfcr = inb(iobase + com_cfcr);
3523	outb(iobase + com_cfcr, CFCR_DLAB | cfcr);
3524
3525	dlbl = inb(iobase + com_dlbl);
3526	dlbh = inb(iobase + com_dlbh);
3527
3528	outb(iobase + com_cfcr, cfcr);
3529
3530	divisor = dlbh << 8 | dlbl;
3531
3532	/* XXX there should be more sanity checking. */
3533	if (divisor == 0)
3534		return (CONSPEED);
3535	return (rclk / (16UL * divisor));
3536}
3537
3538static void
3539siocnopen(sp, iobase, speed)
3540	struct siocnstate	*sp;
3541	Port_t			iobase;
3542	int			speed;
3543{
3544	u_int	divisor;
3545	u_char	dlbh;
3546	u_char	dlbl;
3547
3548	/*
3549	 * Save all the device control registers except the fifo register
3550	 * and set our default ones (cs8 -parenb speed=comdefaultrate).
3551	 * We can't save the fifo register since it is read-only.
3552	 */
3553	sp->ier = inb(iobase + com_ier);
3554	outb(iobase + com_ier, 0);	/* spltty() doesn't stop siointr() */
3555	siocntxwait(iobase);
3556	sp->cfcr = inb(iobase + com_cfcr);
3557	outb(iobase + com_cfcr, CFCR_DLAB | CFCR_8BITS);
3558	sp->dlbl = inb(iobase + com_dlbl);
3559	sp->dlbh = inb(iobase + com_dlbh);
3560	/*
3561	 * Only set the divisor registers if they would change, since on
3562	 * some 16550 incompatibles (Startech), setting them clears the
3563	 * data input register.  This also reduces the effects of the
3564	 * UMC8669F bug.
3565	 */
3566	divisor = siodivisor(comdefaultrclk, speed);
3567	dlbl = divisor & 0xFF;
3568	if (sp->dlbl != dlbl)
3569		outb(iobase + com_dlbl, dlbl);
3570	dlbh = divisor >> 8;
3571	if (sp->dlbh != dlbh)
3572		outb(iobase + com_dlbh, dlbh);
3573	outb(iobase + com_cfcr, CFCR_8BITS);
3574	sp->mcr = inb(iobase + com_mcr);
3575	/*
3576	 * We don't want interrupts, but must be careful not to "disable"
3577	 * them by clearing the MCR_IENABLE bit, since that might cause
3578	 * an interrupt by floating the IRQ line.
3579	 */
3580	outb(iobase + com_mcr, (sp->mcr & MCR_IENABLE) | MCR_DTR | MCR_RTS);
3581}
3582
3583static void
3584siocnclose(sp, iobase)
3585	struct siocnstate	*sp;
3586	Port_t			iobase;
3587{
3588	/*
3589	 * Restore the device control registers.
3590	 */
3591	siocntxwait(iobase);
3592	outb(iobase + com_cfcr, CFCR_DLAB | CFCR_8BITS);
3593	if (sp->dlbl != inb(iobase + com_dlbl))
3594		outb(iobase + com_dlbl, sp->dlbl);
3595	if (sp->dlbh != inb(iobase + com_dlbh))
3596		outb(iobase + com_dlbh, sp->dlbh);
3597	outb(iobase + com_cfcr, sp->cfcr);
3598	/*
3599	 * XXX damp oscillations of MCR_DTR and MCR_RTS by not restoring them.
3600	 */
3601	outb(iobase + com_mcr, sp->mcr | MCR_DTR | MCR_RTS);
3602	outb(iobase + com_ier, sp->ier);
3603}
3604
3605static void
3606sio_cnprobe(cp)
3607	struct consdev	*cp;
3608{
3609	speed_t			boot_speed;
3610	u_char			cfcr;
3611	u_int			divisor;
3612	int			s, unit;
3613	struct siocnstate	sp;
3614
3615	/*
3616	 * Find our first enabled console, if any.  If it is a high-level
3617	 * console device, then initialize it and return successfully.
3618	 * If it is a low-level console device, then initialize it and
3619	 * return unsuccessfully.  It must be initialized in both cases
3620	 * for early use by console drivers and debuggers.  Initializing
3621	 * the hardware is not necessary in all cases, since the i/o
3622	 * routines initialize it on the fly, but it is necessary if
3623	 * input might arrive while the hardware is switched back to an
3624	 * uninitialized state.  We can't handle multiple console devices
3625	 * yet because our low-level routines don't take a device arg.
3626	 * We trust the user to set the console flags properly so that we
3627	 * don't need to probe.
3628	 */
3629	cp->cn_pri = CN_DEAD;
3630
3631	for (unit = 0; unit < 16; unit++) { /* XXX need to know how many */
3632		int flags;
3633
3634		if (resource_disabled("sio", unit))
3635			continue;
3636		if (resource_int_value("sio", unit, "flags", &flags))
3637			continue;
3638		if (COM_CONSOLE(flags) || COM_DEBUGGER(flags)) {
3639			int port;
3640			Port_t iobase;
3641
3642			if (resource_int_value("sio", unit, "port", &port))
3643				continue;
3644			iobase = port;
3645			s = spltty();
3646			if ((boothowto & RB_SERIAL) && COM_CONSOLE(flags)) {
3647				boot_speed =
3648				    siocngetspeed(iobase, comdefaultrclk);
3649				if (boot_speed)
3650					comdefaultrate = boot_speed;
3651			}
3652
3653			/*
3654			 * Initialize the divisor latch.  We can't rely on
3655			 * siocnopen() to do this the first time, since it
3656			 * avoids writing to the latch if the latch appears
3657			 * to have the correct value.  Also, if we didn't
3658			 * just read the speed from the hardware, then we
3659			 * need to set the speed in hardware so that
3660			 * switching it later is null.
3661			 */
3662			cfcr = inb(iobase + com_cfcr);
3663			outb(iobase + com_cfcr, CFCR_DLAB | cfcr);
3664			divisor = siodivisor(comdefaultrclk, comdefaultrate);
3665			outb(iobase + com_dlbl, divisor & 0xff);
3666			outb(iobase + com_dlbh, divisor >> 8);
3667			outb(iobase + com_cfcr, cfcr);
3668
3669			siocnopen(&sp, iobase, comdefaultrate);
3670
3671			splx(s);
3672			if (COM_CONSOLE(flags) && !COM_LLCONSOLE(flags)) {
3673				siocnset(cp, unit);
3674				cp->cn_pri = COM_FORCECONSOLE(flags)
3675					     || boothowto & RB_SERIAL
3676					     ? CN_REMOTE : CN_NORMAL;
3677				siocniobase = iobase;
3678				siocnunit = unit;
3679			}
3680#ifdef GDB
3681			if (COM_DEBUGGER(flags))
3682				siogdbiobase = iobase;
3683#endif
3684		}
3685	}
3686}
3687
3688static void
3689sio_cninit(cp)
3690	struct consdev	*cp;
3691{
3692	comconsole = cp->cn_unit;
3693}
3694
3695static void
3696sio_cnterm(cp)
3697	struct consdev	*cp;
3698{
3699	comconsole = -1;
3700}
3701
3702static int
3703sio_cngetc(struct consdev *cd)
3704{
3705	int	c;
3706	Port_t	iobase;
3707	int	s;
3708	struct siocnstate	sp;
3709	speed_t	speed;
3710
3711	if (cd != NULL && cd->cn_unit == siocnunit) {
3712		iobase = siocniobase;
3713		speed = comdefaultrate;
3714	} else {
3715#ifdef GDB
3716		iobase = siogdbiobase;
3717		speed = gdbdefaultrate;
3718#else
3719		return (-1);
3720#endif
3721	}
3722	s = spltty();
3723	siocnopen(&sp, iobase, speed);
3724	if (inb(iobase + com_lsr) & LSR_RXRDY)
3725		c = inb(iobase + com_data);
3726	else
3727		c = -1;
3728	siocnclose(&sp, iobase);
3729	splx(s);
3730	return (c);
3731}
3732
3733static void
3734sio_cnputc(struct consdev *cd, int c)
3735{
3736	int	need_unlock;
3737	int	s;
3738	struct siocnstate	sp;
3739	Port_t	iobase;
3740	speed_t	speed;
3741
3742	if (cd != NULL && cd->cn_unit == siocnunit) {
3743		iobase = siocniobase;
3744		speed = comdefaultrate;
3745	} else {
3746#ifdef GDB
3747		iobase = siogdbiobase;
3748		speed = gdbdefaultrate;
3749#else
3750		return;
3751#endif
3752	}
3753	s = spltty();
3754	need_unlock = 0;
3755	if (!kdb_active && sio_inited == 2 && !mtx_owned(&sio_lock)) {
3756		mtx_lock_spin(&sio_lock);
3757		need_unlock = 1;
3758	}
3759	siocnopen(&sp, iobase, speed);
3760	siocntxwait(iobase);
3761	outb(iobase + com_data, c);
3762	siocnclose(&sp, iobase);
3763	if (need_unlock)
3764		mtx_unlock_spin(&sio_lock);
3765	splx(s);
3766}
3767
3768/*
3769 * Remote gdb(1) support.
3770 */
3771
3772#if defined(GDB)
3773
3774#include <gdb/gdb.h>
3775
3776static gdb_probe_f siogdbprobe;
3777static gdb_init_f siogdbinit;
3778static gdb_term_f siogdbterm;
3779static gdb_getc_f siogdbgetc;
3780static gdb_putc_f siogdbputc;
3781
3782GDB_DBGPORT(sio, siogdbprobe, siogdbinit, siogdbterm, siogdbgetc, siogdbputc);
3783
3784static int
3785siogdbprobe(void)
3786{
3787	return ((siogdbiobase != 0) ? 0 : -1);
3788}
3789
3790static void
3791siogdbinit(void)
3792{
3793}
3794
3795static void
3796siogdbterm(void)
3797{
3798}
3799
3800static void
3801siogdbputc(int c)
3802{
3803	sio_cnputc(NULL, c);
3804}
3805
3806static int
3807siogdbgetc(void)
3808{
3809	return (sio_cngetc(NULL));
3810}
3811
3812#endif
3813
3814#ifdef PC98
3815/*
3816 *  pc98 local function
3817 */
3818static void
3819com_tiocm_bis(struct com_s *com, int msr)
3820{
3821	int	s;
3822	int	tmp = 0;
3823
3824	s=spltty();
3825	com->pc98_prev_modem_status |= ( msr & (TIOCM_LE|TIOCM_DTR|TIOCM_RTS) );
3826	tmp |= CMD8251_TxEN|CMD8251_RxEN;
3827	if ( msr & TIOCM_DTR ) tmp |= CMD8251_DTR;
3828	if ( msr & TIOCM_RTS ) tmp |= CMD8251_RTS;
3829
3830	pc98_i8251_or_cmd( com, tmp );
3831	splx(s);
3832}
3833
3834static void
3835com_tiocm_bic(struct com_s *com, int msr)
3836{
3837	int	s;
3838	int	tmp = msr;
3839
3840	s=spltty();
3841	com->pc98_prev_modem_status &= ~( msr & (TIOCM_LE|TIOCM_DTR|TIOCM_RTS) );
3842	if ( msr & TIOCM_DTR ) tmp |= CMD8251_DTR;
3843	if ( msr & TIOCM_RTS ) tmp |= CMD8251_RTS;
3844
3845	pc98_i8251_clear_cmd( com, tmp );
3846	splx(s);
3847}
3848
3849static int
3850com_tiocm_get(struct com_s *com)
3851{
3852	return( com->pc98_prev_modem_status );
3853}
3854
3855static int
3856com_tiocm_get_delta(struct com_s *com)
3857{
3858	int	tmp;
3859
3860	tmp = com->pc98_modem_delta;
3861	com->pc98_modem_delta = 0;
3862	return( tmp );
3863}
3864
3865/* convert to TIOCM_?? ( ioctl.h ) */
3866static int
3867pc98_get_modem_status(struct com_s *com)
3868{
3869	register int	msr;
3870
3871	msr = com->pc98_prev_modem_status
3872			& ~(TIOCM_CAR|TIOCM_RI|TIOCM_DSR|TIOCM_CTS);
3873	if (com->pc98_8251fifo_enable) {
3874		int	stat2;
3875
3876		stat2 = inb(I8251F_msr);
3877		if ( stat2 & MSR_DCD ) msr |= TIOCM_CAR;
3878		if ( stat2 & MSR_RI ) msr |= TIOCM_RI;
3879		if ( stat2 & MSR_DSR ) msr |= TIOCM_DSR;
3880		if ( stat2 & MSR_CTS ) msr |= TIOCM_CTS;
3881#if COM_CARRIER_DETECT_EMULATE
3882		if ( msr & (TIOCM_DSR|TIOCM_CTS) ) {
3883			msr |= TIOCM_CAR;
3884		}
3885#endif
3886	} else {
3887		int	stat, stat2;
3888
3889		stat  = inb(com->sts_port);
3890		stat2 = inb(com->in_modem_port);
3891		if ( !(stat2 & CICSCD_CD) ) msr |= TIOCM_CAR;
3892		if ( !(stat2 & CICSCD_CI) ) msr |= TIOCM_RI;
3893		if (   stat & STS8251_DSR ) msr |= TIOCM_DSR;
3894		if ( !(stat2 & CICSCD_CS) ) msr |= TIOCM_CTS;
3895#if COM_CARRIER_DETECT_EMULATE
3896		if ( msr & (TIOCM_DSR|TIOCM_CTS) ) {
3897			msr |= TIOCM_CAR;
3898		}
3899#endif
3900	}
3901	return(msr);
3902}
3903
3904static void
3905pc98_check_msr(void* chan)
3906{
3907	int	msr, delta;
3908	int	s;
3909	register struct tty *tp;
3910	struct	com_s *com;
3911	struct cdev *dev;
3912
3913	dev=(struct cdev *)chan;
3914	com = dev->si_drv1;
3915	tp = dev->si_tty;
3916
3917	s = spltty();
3918	msr = pc98_get_modem_status(com);
3919	/* make change flag */
3920	delta = msr ^ com->pc98_prev_modem_status;
3921	if ( delta & TIOCM_CAR ) {
3922	    if ( com->modem_car_chg_timer ) {
3923		if ( -- com->modem_car_chg_timer )
3924		    msr ^= TIOCM_CAR;
3925	    } else {
3926		if ((com->modem_car_chg_timer = (msr & TIOCM_CAR) ?
3927		     DCD_ON_RECOGNITION : DCD_OFF_TOLERANCE) != 0)
3928		    msr ^= TIOCM_CAR;
3929	    }
3930	} else
3931	    com->modem_car_chg_timer = 0;
3932	delta = ( msr ^ com->pc98_prev_modem_status ) &
3933			(TIOCM_CAR|TIOCM_RI|TIOCM_DSR|TIOCM_CTS);
3934	com->pc98_prev_modem_status = msr;
3935	delta = ( com->pc98_modem_delta |= delta );
3936	splx(s);
3937	if ( com->modem_checking || (tp->t_state & (TS_ISOPEN)) ) {
3938		if ( delta ) {
3939			commint(dev);
3940		}
3941		timeout(pc98_check_msr, (caddr_t)dev,
3942					PC98_CHECK_MODEM_INTERVAL);
3943	} else {
3944		com->modem_checking = 0;
3945	}
3946}
3947
3948static void
3949pc98_msrint_start(struct cdev *dev)
3950{
3951	struct	com_s *com;
3952	int	s = spltty();
3953
3954	com = dev->si_drv1;
3955	/* modem control line check routine envoke interval is 1/10 sec */
3956	if ( com->modem_checking == 0 ) {
3957		com->pc98_prev_modem_status = pc98_get_modem_status(com);
3958		com->pc98_modem_delta = 0;
3959		timeout(pc98_check_msr, (caddr_t)dev,
3960					PC98_CHECK_MODEM_INTERVAL);
3961		com->modem_checking = 1;
3962	}
3963	splx(s);
3964}
3965
3966static void
3967pc98_disable_i8251_interrupt(struct com_s *com, int mod)
3968{
3969	/* disable interrupt */
3970	register int	tmp;
3971
3972	mod |= ~(IEN_Tx|IEN_TxEMP|IEN_Rx);
3973	COM_INT_DISABLE
3974	tmp = inb( com->intr_ctrl_port ) & ~(IEN_Tx|IEN_TxEMP|IEN_Rx);
3975	outb( com->intr_ctrl_port, (com->intr_enable&=~mod) | tmp );
3976	COM_INT_ENABLE
3977}
3978
3979static void
3980pc98_enable_i8251_interrupt(struct com_s *com, int mod)
3981{
3982	register int	tmp;
3983
3984	COM_INT_DISABLE
3985	tmp = inb( com->intr_ctrl_port ) & ~(IEN_Tx|IEN_TxEMP|IEN_Rx);
3986	outb( com->intr_ctrl_port, (com->intr_enable|=mod) | tmp );
3987	COM_INT_ENABLE
3988}
3989
3990static int
3991pc98_check_i8251_interrupt(struct com_s *com)
3992{
3993	return ( com->intr_enable & 0x07 );
3994}
3995
3996static void
3997pc98_i8251_clear_cmd(struct com_s *com, int x)
3998{
3999	int	tmp;
4000
4001	COM_INT_DISABLE
4002	tmp = com->pc98_prev_siocmd & ~(x);
4003	if (com->pc98_8251fifo_enable)
4004	    outb(I8251F_fcr, 0);
4005	outb(com->cmd_port, tmp);
4006	com->pc98_prev_siocmd = tmp & ~(CMD8251_ER|CMD8251_RESET|CMD8251_EH);
4007	if (com->pc98_8251fifo_enable)
4008	    outb(I8251F_fcr, FIFO_ENABLE);
4009	COM_INT_ENABLE
4010}
4011
4012static void
4013pc98_i8251_or_cmd(struct com_s *com, int x)
4014{
4015	int	tmp;
4016
4017	COM_INT_DISABLE
4018	if (com->pc98_8251fifo_enable)
4019	    outb(I8251F_fcr, 0);
4020	tmp = com->pc98_prev_siocmd | (x);
4021	outb(com->cmd_port, tmp);
4022	com->pc98_prev_siocmd = tmp & ~(CMD8251_ER|CMD8251_RESET|CMD8251_EH);
4023	if (com->pc98_8251fifo_enable)
4024	    outb(I8251F_fcr, FIFO_ENABLE);
4025	COM_INT_ENABLE
4026}
4027
4028static void
4029pc98_i8251_set_cmd(struct com_s *com, int x)
4030{
4031	int	tmp;
4032
4033	COM_INT_DISABLE
4034	if (com->pc98_8251fifo_enable)
4035	    outb(I8251F_fcr, 0);
4036	tmp = (x);
4037	outb(com->cmd_port, tmp);
4038	com->pc98_prev_siocmd = tmp & ~(CMD8251_ER|CMD8251_RESET|CMD8251_EH);
4039	if (com->pc98_8251fifo_enable)
4040	    outb(I8251F_fcr, FIFO_ENABLE);
4041	COM_INT_ENABLE
4042}
4043
4044static void
4045pc98_i8251_clear_or_cmd(struct com_s *com, int clr, int x)
4046{
4047	int	tmp;
4048	COM_INT_DISABLE
4049	if (com->pc98_8251fifo_enable)
4050	    outb(I8251F_fcr, 0);
4051	tmp = com->pc98_prev_siocmd & ~(clr);
4052	tmp |= (x);
4053	outb(com->cmd_port, tmp);
4054	com->pc98_prev_siocmd = tmp & ~(CMD8251_ER|CMD8251_RESET|CMD8251_EH);
4055	if (com->pc98_8251fifo_enable)
4056	    outb(I8251F_fcr, FIFO_ENABLE);
4057	COM_INT_ENABLE
4058}
4059
4060static int
4061pc98_i8251_get_cmd(struct com_s *com)
4062{
4063	return com->pc98_prev_siocmd;
4064}
4065
4066static int
4067pc98_i8251_get_mod(struct com_s *com)
4068{
4069	return com->pc98_prev_siomod;
4070}
4071
4072static void
4073pc98_i8251_reset(struct com_s *com, int mode, int command)
4074{
4075	if (com->pc98_8251fifo_enable)
4076	    outb(I8251F_fcr, 0);
4077	outb(com->cmd_port, 0);	/* dummy */
4078	DELAY(2);
4079	outb(com->cmd_port, 0);	/* dummy */
4080	DELAY(2);
4081	outb(com->cmd_port, 0);	/* dummy */
4082	DELAY(2);
4083	outb(com->cmd_port, CMD8251_RESET);	/* internal reset */
4084	DELAY(2);
4085	outb(com->cmd_port, mode );	/* mode register */
4086	com->pc98_prev_siomod = mode;
4087	DELAY(2);
4088	pc98_i8251_set_cmd( com, (command|CMD8251_ER) );
4089	DELAY(10);
4090	if (com->pc98_8251fifo_enable)
4091	    outb(I8251F_fcr, FIFO_ENABLE | FIFO_XMT_RST | FIFO_RCV_RST);
4092}
4093
4094static void
4095pc98_check_sysclock(void)
4096{
4097	/* get system clock from port */
4098	if ( pc98_machine_type & M_8M ) {
4099	/* 8 MHz system & H98 */
4100		sysclock = 8;
4101	} else {
4102	/* 5 MHz system */
4103		sysclock = 5;
4104	}
4105}
4106
4107static void
4108com_cflag_and_speed_set( struct com_s *com, int cflag, int speed)
4109{
4110	int	cfcr=0;
4111	int	previnterrupt;
4112	int	tmp;
4113	u_int	count;
4114
4115	if (pc98_ttspeedtab(com, speed, &count) != 0)
4116		return;
4117
4118	previnterrupt = pc98_check_i8251_interrupt(com);
4119	pc98_disable_i8251_interrupt( com, IEN_Tx|IEN_TxEMP|IEN_Rx );
4120
4121	switch ( cflag&CSIZE ) {
4122	  case CS5:
4123		cfcr = MOD8251_5BITS; break;
4124	  case CS6:
4125		cfcr = MOD8251_6BITS; break;
4126	  case CS7:
4127		cfcr = MOD8251_7BITS; break;
4128	  case CS8:
4129		cfcr = MOD8251_8BITS; break;
4130	}
4131	if ( cflag&PARENB ) {
4132	    if ( cflag&PARODD )
4133		cfcr |= MOD8251_PENAB;
4134	    else
4135		cfcr |= MOD8251_PENAB | MOD8251_PEVEN;
4136	}
4137
4138	if ( cflag&CSTOPB )
4139		cfcr |= MOD8251_STOP2;
4140	else
4141		cfcr |= MOD8251_STOP1;
4142
4143	if ( count & 0x10000 )
4144		cfcr |= MOD8251_CLKx1;
4145	else
4146		cfcr |= MOD8251_CLKx16;
4147
4148	while (!((tmp = inb(com->sts_port)) & STS8251_TxEMP))
4149		;
4150
4151	/* set baud rate from ospeed */
4152	pc98_set_baud_rate( com, count );
4153
4154	if ( cfcr != pc98_i8251_get_mod(com) )
4155		pc98_i8251_reset(com, cfcr, pc98_i8251_get_cmd(com) );
4156
4157	pc98_enable_i8251_interrupt( com, previnterrupt );
4158}
4159
4160static int
4161pc98_ttspeedtab(struct com_s *com, int speed, u_int *divisor)
4162{
4163	int	if_type, effect_sp, count = -1, mod;
4164
4165	if_type = com->pc98_if_type & 0x0f;
4166
4167	switch (com->pc98_if_type) {
4168	case COM_IF_INTERNAL:
4169	    if (PC98SIO_baud_rate_port(if_type) != -1) {
4170		count = ttspeedtab(speed, if_8251_type[if_type].speedtab);
4171		if (count > 0) {
4172		    count |= COM1_EXT_CLOCK;
4173		    break;
4174		}
4175	    }
4176
4177	    /* for *1CLK asynchronous! mode, TEFUTEFU */
4178	    mod = (sysclock == 5) ? 2457600 : 1996800;
4179	    effect_sp = ttspeedtab( speed, pc98speedtab );
4180	    if ( effect_sp < 0 )	/* XXX */
4181		effect_sp = ttspeedtab( (speed - 1), pc98speedtab );
4182	    if ( effect_sp <= 0 )
4183		return effect_sp;
4184	    if ( effect_sp == speed )
4185		mod /= 16;
4186	    if ( mod % effect_sp )
4187		return(-1);
4188	    count = mod / effect_sp;
4189	    if ( count > 65535 )
4190		return(-1);
4191	    if ( effect_sp != speed )
4192		count |= 0x10000;
4193	    break;
4194	case COM_IF_PC9861K_1:
4195	case COM_IF_PC9861K_2:
4196	    count = 1;
4197	    break;
4198	case COM_IF_IND_SS_1:
4199	case COM_IF_IND_SS_2:
4200	case COM_IF_PIO9032B_1:
4201	case COM_IF_PIO9032B_2:
4202	    count = ttspeedtab( speed, if_8251_type[if_type].speedtab );
4203	    break;
4204	case COM_IF_B98_01_1:
4205	case COM_IF_B98_01_2:
4206	    count = ttspeedtab( speed, if_8251_type[if_type].speedtab );
4207#ifdef B98_01_OLD
4208	    if (count == 0 || count == 1) {
4209		count += 4;
4210		count |= 0x20000;  /* x1 mode for 76800 and 153600 */
4211	    }
4212#endif
4213	    break;
4214	}
4215
4216	if (count < 0)
4217		return count;
4218
4219	*divisor = (u_int) count;
4220	return 0;
4221}
4222
4223static void
4224pc98_set_baud_rate( struct com_s *com, u_int count )
4225{
4226	int	if_type, io, s;
4227
4228	if_type = com->pc98_if_type & 0x0f;
4229	io = rman_get_start(com->ioportres) & 0xff00;
4230
4231	switch (com->pc98_if_type) {
4232	case COM_IF_INTERNAL:
4233	    if (PC98SIO_baud_rate_port(if_type) != -1) {
4234		if (count & COM1_EXT_CLOCK) {
4235		    outb((Port_t)PC98SIO_baud_rate_port(if_type), count & 0xff);
4236		    break;
4237		} else {
4238		    outb((Port_t)PC98SIO_baud_rate_port(if_type), 0x09);
4239		}
4240	    }
4241
4242	    if (count == 0)
4243		return;
4244
4245	    /* set i8253 */
4246	    s = splclock();
4247	    if (count != 3)
4248		outb( 0x77, 0xb6 );
4249	    else
4250		outb( 0x77, 0xb4 );
4251	    outb( 0x5f, 0);
4252	    outb( 0x75, count & 0xff );
4253	    outb( 0x5f, 0);
4254	    outb( 0x75, (count >> 8) & 0xff );
4255	    splx(s);
4256	    break;
4257	case COM_IF_IND_SS_1:
4258	case COM_IF_IND_SS_2:
4259	    outb(io | PC98SIO_intr_ctrl_port(if_type), 0);
4260	    outb(io | PC98SIO_baud_rate_port(if_type), 0);
4261	    outb(io | PC98SIO_baud_rate_port(if_type), 0xc0);
4262	    outb(io | PC98SIO_baud_rate_port(if_type), (count >> 8) | 0x80);
4263	    outb(io | PC98SIO_baud_rate_port(if_type), count & 0xff);
4264	    break;
4265	case COM_IF_PIO9032B_1:
4266	case COM_IF_PIO9032B_2:
4267	    outb(io | PC98SIO_baud_rate_port(if_type), count);
4268	    break;
4269	case COM_IF_B98_01_1:
4270	case COM_IF_B98_01_2:
4271	    outb(io | PC98SIO_baud_rate_port(if_type), count & 0x0f);
4272#ifdef B98_01_OLD
4273	    /*
4274	     * Some old B98_01 board should be controlled
4275	     * in different way, but this hasn't been tested yet.
4276	     */
4277	    outb(io | PC98SIO_func_port(if_type),
4278		 (count & 0x20000) ? 0xf0 : 0xf2);
4279#endif
4280	    break;
4281	}
4282}
4283static int
4284pc98_check_if_type(device_t dev, struct siodev *iod)
4285{
4286	int	irr, io, if_type, tmp;
4287	static  short	irq_tab[2][8] = {
4288		{  3,  5,  6,  9, 10, 12, 13, -1},
4289		{  3, 10, 12, 13,  5,  6,  9, -1}
4290	};
4291
4292	if_type = iod->if_type & 0x0f;
4293	iod->irq = 0;
4294	io = isa_get_port(dev) & 0xff00;
4295
4296	if (IS_8251(iod->if_type)) {
4297	    if (PC98SIO_func_port(if_type) != -1) {
4298		outb(io | PC98SIO_func_port(if_type), 0xf2);
4299		tmp = ttspeedtab(9600, if_8251_type[if_type].speedtab);
4300		if (tmp != -1 && PC98SIO_baud_rate_port(if_type) != -1)
4301		    outb(io | PC98SIO_baud_rate_port(if_type), tmp);
4302	    }
4303
4304	    iod->cmd  = io | PC98SIO_cmd_port(if_type);
4305	    iod->sts  = io | PC98SIO_sts_port(if_type);
4306	    iod->mod  = io | PC98SIO_in_modem_port(if_type);
4307	    iod->ctrl = io | PC98SIO_intr_ctrl_port(if_type);
4308
4309	    if (iod->if_type == COM_IF_INTERNAL) {
4310		iod->irq = 4;
4311
4312		if (pc98_check_8251vfast()) {
4313			PC98SIO_baud_rate_port(if_type) = I8251F_div;
4314			if_8251_type[if_type].speedtab = pc98fast_speedtab;
4315		}
4316	    } else {
4317		tmp = inb( iod->mod ) & if_8251_type[if_type].irr_mask;
4318		if ((isa_get_port(dev) & 0xff) == IO_COM2)
4319		    iod->irq = irq_tab[0][tmp];
4320		else
4321		    iod->irq = irq_tab[1][tmp];
4322	    }
4323	} else {
4324	    irr = if_16550a_type[if_type].irr_read;
4325#ifdef COM_MULTIPORT
4326	    if (!COM_ISMULTIPORT(device_get_flags(dev)) ||
4327		    device_get_unit(dev) == COM_MPMASTER(device_get_flags(dev)))
4328#endif
4329	    if (irr != -1) {
4330		tmp = inb(io | irr);
4331		if (isa_get_port(dev) & 0x01)	/* XXX depend on RSB-384 */
4332		    iod->irq = irq_tab[1][tmp >> 3];
4333		else
4334		    iod->irq = irq_tab[0][tmp & 0x07];
4335	    }
4336	    iod->cmd  = 0;
4337	    iod->sts  = 0;
4338	    iod->mod  = 0;
4339	    iod->ctrl = 0;
4340	}
4341	if ( iod->irq == -1 ) return -1;
4342
4343	return 0;
4344}
4345static void
4346pc98_set_ioport(struct com_s *com)
4347{
4348	int	if_type = com->pc98_if_type & 0x0f;
4349	Port_t	io = rman_get_start(com->ioportres) & 0xff00;
4350
4351	pc98_check_sysclock();
4352	com->data_port		= io | PC98SIO_data_port(if_type);
4353	com->cmd_port		= io | PC98SIO_cmd_port(if_type);
4354	com->sts_port		= io | PC98SIO_sts_port(if_type);
4355	com->in_modem_port	= io | PC98SIO_in_modem_port(if_type);
4356	com->intr_ctrl_port	= io | PC98SIO_intr_ctrl_port(if_type);
4357}
4358static int
4359pc98_check_8251vfast(void)
4360{
4361    int	i;
4362
4363    outb(I8251F_div, 0x8c);
4364    DELAY(10);
4365    for (i = 0; i < 100; i++) {
4366	if ((inb(I8251F_div) & 0x80) != 0) {
4367	    i = 0;
4368	    break;
4369	}
4370	DELAY(1);
4371    }
4372    outb(I8251F_div, 0);
4373    DELAY(10);
4374    for (; i < 100; i++) {
4375	if ((inb(I8251F_div) & 0x80) == 0)
4376	    return 1;
4377	DELAY(1);
4378    }
4379
4380    return 0;
4381}
4382static int
4383pc98_check_8251fifo(void)
4384{
4385    u_char	tmp1, tmp2;
4386
4387    tmp1 = inb(I8251F_iir);
4388    DELAY(10);
4389    tmp2 = inb(I8251F_iir);
4390    if (((tmp1 ^ tmp2) & 0x40) != 0 && ((tmp1 | tmp2) & 0x20) == 0)
4391	return 1;
4392
4393    return 0;
4394}
4395#endif /* PC98 defined */
4396