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com.c revision 1.322
      1 /* $NetBSD: com.c,v 1.322 2013/12/22 18:20:46 matt Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 1998, 1999, 2004, 2008 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Charles M. Hannum.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 /*
     33  * Copyright (c) 1991 The Regents of the University of California.
     34  * All rights reserved.
     35  *
     36  * Redistribution and use in source and binary forms, with or without
     37  * modification, are permitted provided that the following conditions
     38  * are met:
     39  * 1. Redistributions of source code must retain the above copyright
     40  *    notice, this list of conditions and the following disclaimer.
     41  * 2. Redistributions in binary form must reproduce the above copyright
     42  *    notice, this list of conditions and the following disclaimer in the
     43  *    documentation and/or other materials provided with the distribution.
     44  * 3. Neither the name of the University nor the names of its contributors
     45  *    may be used to endorse or promote products derived from this software
     46  *    without specific prior written permission.
     47  *
     48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     58  * SUCH DAMAGE.
     59  *
     60  *	@(#)com.c	7.5 (Berkeley) 5/16/91
     61  */
     62 
     63 /*
     64  * COM driver, uses National Semiconductor NS16450/NS16550AF UART
     65  * Supports automatic hardware flow control on StarTech ST16C650A UART
     66  */
     67 
     68 #include <sys/cdefs.h>
     69 __KERNEL_RCSID(0, "$NetBSD: com.c,v 1.322 2013/12/22 18:20:46 matt Exp $");
     70 
     71 #include "opt_com.h"
     72 #include "opt_ddb.h"
     73 #include "opt_kgdb.h"
     74 #include "opt_lockdebug.h"
     75 #include "opt_multiprocessor.h"
     76 #include "opt_ntp.h"
     77 
     78 #include "rnd.h"
     79 
     80 /* The COM16650 option was renamed to COM_16650. */
     81 #ifdef COM16650
     82 #error Obsolete COM16650 option; use COM_16650 instead.
     83 #endif
     84 
     85 /*
     86  * Override cnmagic(9) macro before including <sys/systm.h>.
     87  * We need to know if cn_check_magic triggered debugger, so set a flag.
     88  * Callers of cn_check_magic must declare int cn_trapped = 0;
     89  * XXX: this is *ugly*!
     90  */
     91 #define cn_trap()				\
     92 	do {					\
     93 		console_debugger();		\
     94 		cn_trapped = 1;			\
     95 		(void)cn_trapped;		\
     96 	} while (/* CONSTCOND */ 0)
     97 
     98 #include <sys/param.h>
     99 #include <sys/systm.h>
    100 #include <sys/ioctl.h>
    101 #include <sys/select.h>
    102 #include <sys/poll.h>
    103 #include <sys/tty.h>
    104 #include <sys/proc.h>
    105 #include <sys/conf.h>
    106 #include <sys/file.h>
    107 #include <sys/uio.h>
    108 #include <sys/kernel.h>
    109 #include <sys/syslog.h>
    110 #include <sys/device.h>
    111 #include <sys/malloc.h>
    112 #include <sys/timepps.h>
    113 #include <sys/vnode.h>
    114 #include <sys/kauth.h>
    115 #include <sys/intr.h>
    116 #ifdef RND_COM
    117 #include <sys/rnd.h>
    118 #endif
    119 
    120 
    121 #include <sys/bus.h>
    122 
    123 #include <dev/ic/comreg.h>
    124 #include <dev/ic/comvar.h>
    125 #include <dev/ic/ns16550reg.h>
    126 #include <dev/ic/st16650reg.h>
    127 #ifdef COM_HAYESP
    128 #include <dev/ic/hayespreg.h>
    129 #endif
    130 #define	com_lcr	com_cfcr
    131 #include <dev/cons.h>
    132 
    133 #ifdef	COM_REGMAP
    134 #define	CSR_WRITE_1(r, o, v)	\
    135 	bus_space_write_1((r)->cr_iot, (r)->cr_ioh, (r)->cr_map[o], v)
    136 #define	CSR_READ_1(r, o)	\
    137 	bus_space_read_1((r)->cr_iot, (r)->cr_ioh, (r)->cr_map[o])
    138 #define	CSR_WRITE_2(r, o, v)	\
    139 	bus_space_write_2((r)->cr_iot, (r)->cr_ioh, (r)->cr_map[o], v)
    140 #define	CSR_READ_2(r, o)	\
    141 	bus_space_read_2((r)->cr_iot, (r)->cr_ioh, (r)->cr_map[o])
    142 #define	CSR_WRITE_MULTI(r, o, p, n)	\
    143 	bus_space_write_multi_1((r)->cr_iot, (r)->cr_ioh, (r)->cr_map[o], p, n)
    144 #else
    145 #define	CSR_WRITE_1(r, o, v)	\
    146 	bus_space_write_1((r)->cr_iot, (r)->cr_ioh, o, v)
    147 #define	CSR_READ_1(r, o)	\
    148 	bus_space_read_1((r)->cr_iot, (r)->cr_ioh, o)
    149 #define	CSR_WRITE_2(r, o, v)	\
    150 	bus_space_write_2((r)->cr_iot, (r)->cr_ioh, o, v)
    151 #define	CSR_READ_2(r, o)	\
    152 	bus_space_read_2((r)->cr_iot, (r)->cr_ioh, o)
    153 #define	CSR_WRITE_MULTI(r, o, p, n)	\
    154 	bus_space_write_multi_1((r)->cr_iot, (r)->cr_ioh, o, p, n)
    155 #endif
    156 
    157 
    158 static void com_enable_debugport(struct com_softc *);
    159 
    160 void	com_config(struct com_softc *);
    161 void	com_shutdown(struct com_softc *);
    162 int	comspeed(long, long, int);
    163 static	u_char	cflag2lcr(tcflag_t);
    164 int	comparam(struct tty *, struct termios *);
    165 void	comstart(struct tty *);
    166 int	comhwiflow(struct tty *, int);
    167 
    168 void	com_loadchannelregs(struct com_softc *);
    169 void	com_hwiflow(struct com_softc *);
    170 void	com_break(struct com_softc *, int);
    171 void	com_modem(struct com_softc *, int);
    172 void	tiocm_to_com(struct com_softc *, u_long, int);
    173 int	com_to_tiocm(struct com_softc *);
    174 void	com_iflush(struct com_softc *);
    175 
    176 int	com_common_getc(dev_t, struct com_regs *);
    177 static void	com_common_putc(dev_t, struct com_regs *, int);
    178 
    179 int	cominit(struct com_regs *, int, int, int, tcflag_t);
    180 
    181 static int comcnreattach(void);
    182 
    183 int	comcngetc(dev_t);
    184 void	comcnputc(dev_t, int);
    185 void	comcnpollc(dev_t, int);
    186 
    187 #define	integrate	static inline
    188 void	comsoft(void *);
    189 integrate void com_rxsoft(struct com_softc *, struct tty *);
    190 integrate void com_txsoft(struct com_softc *, struct tty *);
    191 integrate void com_stsoft(struct com_softc *, struct tty *);
    192 integrate void com_schedrx(struct com_softc *);
    193 void	comdiag(void *);
    194 
    195 extern struct cfdriver com_cd;
    196 
    197 dev_type_open(comopen);
    198 dev_type_close(comclose);
    199 dev_type_read(comread);
    200 dev_type_write(comwrite);
    201 dev_type_ioctl(comioctl);
    202 dev_type_stop(comstop);
    203 dev_type_tty(comtty);
    204 dev_type_poll(compoll);
    205 
    206 static struct comcons_info comcons_info;
    207 
    208 /*
    209  * Following are all routines needed for COM to act as console
    210  */
    211 static struct consdev comcons = {
    212 	NULL, NULL, comcngetc, comcnputc, comcnpollc, NULL, NULL, NULL,
    213 	NODEV, CN_NORMAL
    214 };
    215 
    216 
    217 const struct cdevsw com_cdevsw = {
    218 	comopen, comclose, comread, comwrite, comioctl,
    219 	comstop, comtty, compoll, nommap, ttykqfilter, D_TTY
    220 };
    221 
    222 /*
    223  * Make this an option variable one can patch.
    224  * But be warned:  this must be a power of 2!
    225  */
    226 u_int com_rbuf_size = COM_RING_SIZE;
    227 
    228 /* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
    229 u_int com_rbuf_hiwat = (COM_RING_SIZE * 1) / 4;
    230 u_int com_rbuf_lowat = (COM_RING_SIZE * 3) / 4;
    231 
    232 static int comconsattached;
    233 static struct cnm_state com_cnm_state;
    234 
    235 #ifdef KGDB
    236 #include <sys/kgdb.h>
    237 
    238 static struct com_regs comkgdbregs;
    239 static int com_kgdb_attached;
    240 
    241 int	com_kgdb_getc(void *);
    242 void	com_kgdb_putc(void *, int);
    243 #endif /* KGDB */
    244 
    245 #ifdef COM_REGMAP
    246 /* initializer for typical 16550-ish hardware */
    247 #define	COM_REG_16550	{ \
    248 	com_data, com_data, com_dlbl, com_dlbh, com_ier, com_iir, com_fifo, \
    249 	com_efr, com_lcr, com_mcr, com_lsr, com_msr }
    250 /* 16750-specific register set, additional UART status register */
    251 #define	COM_REG_16750	{ \
    252 	com_data, com_data, com_dlbl, com_dlbh, com_ier, com_iir, com_fifo, \
    253 	com_efr, com_lcr, com_mcr, com_lsr, com_msr, 0, 0, 0, 0, 0, 0, 0, 0, \
    254 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, com_usr }
    255 
    256 #ifdef COM_16750
    257 const bus_size_t com_std_map[32] = COM_REG_16750;
    258 #else
    259 const bus_size_t com_std_map[16] = COM_REG_16550;
    260 #endif /* COM_16750 */
    261 #endif /* COM_REGMAP */
    262 
    263 #define	COMUNIT_MASK	0x7ffff
    264 #define	COMDIALOUT_MASK	0x80000
    265 
    266 #define	COMUNIT(x)	(minor(x) & COMUNIT_MASK)
    267 #define	COMDIALOUT(x)	(minor(x) & COMDIALOUT_MASK)
    268 
    269 #define	COM_ISALIVE(sc)	((sc)->enabled != 0 && \
    270 			 device_is_active((sc)->sc_dev))
    271 
    272 #define	BR	BUS_SPACE_BARRIER_READ
    273 #define	BW	BUS_SPACE_BARRIER_WRITE
    274 #define COM_BARRIER(r, f) \
    275 	bus_space_barrier((r)->cr_iot, (r)->cr_ioh, 0, (r)->cr_nports, (f))
    276 
    277 /*ARGSUSED*/
    278 int
    279 comspeed(long speed, long frequency, int type)
    280 {
    281 #define	divrnd(n, q)	(((n)*2/(q)+1)/2)	/* divide and round off */
    282 
    283 	int x, err;
    284 	int divisor = 16;
    285 
    286 	if ((type == COM_TYPE_OMAP) && (speed > 230400)) {
    287 	    divisor = 13;
    288 	}
    289 
    290 #if 0
    291 	if (speed == 0)
    292 		return (0);
    293 #endif
    294 	if (speed <= 0)
    295 		return (-1);
    296 	x = divrnd(frequency / divisor, speed);
    297 	if (x <= 0)
    298 		return (-1);
    299 	err = divrnd(((quad_t)frequency) * 1000 / divisor, speed * x) - 1000;
    300 	if (err < 0)
    301 		err = -err;
    302 	if (err > COM_TOLERANCE)
    303 		return (-1);
    304 	return (x);
    305 
    306 #undef	divrnd
    307 }
    308 
    309 #ifdef COM_DEBUG
    310 int	com_debug = 0;
    311 
    312 void comstatus(struct com_softc *, const char *);
    313 void
    314 comstatus(struct com_softc *sc, const char *str)
    315 {
    316 	struct tty *tp = sc->sc_tty;
    317 
    318 	aprint_normal_dev(sc->sc_dev,
    319 	    "%s %cclocal  %cdcd %cts_carr_on %cdtr %ctx_stopped\n",
    320 	    str,
    321 	    ISSET(tp->t_cflag, CLOCAL) ? '+' : '-',
    322 	    ISSET(sc->sc_msr, MSR_DCD) ? '+' : '-',
    323 	    ISSET(tp->t_state, TS_CARR_ON) ? '+' : '-',
    324 	    ISSET(sc->sc_mcr, MCR_DTR) ? '+' : '-',
    325 	    sc->sc_tx_stopped ? '+' : '-');
    326 
    327 	aprint_normal_dev(sc->sc_dev,
    328 	    "%s %ccrtscts %ccts %cts_ttstop  %crts rx_flags=0x%x\n",
    329 	    str,
    330 	    ISSET(tp->t_cflag, CRTSCTS) ? '+' : '-',
    331 	    ISSET(sc->sc_msr, MSR_CTS) ? '+' : '-',
    332 	    ISSET(tp->t_state, TS_TTSTOP) ? '+' : '-',
    333 	    ISSET(sc->sc_mcr, MCR_RTS) ? '+' : '-',
    334 	    sc->sc_rx_flags);
    335 }
    336 #endif
    337 
    338 int
    339 com_probe_subr(struct com_regs *regs)
    340 {
    341 
    342 	/* force access to id reg */
    343 	CSR_WRITE_1(regs, COM_REG_LCR, LCR_8BITS);
    344 	CSR_WRITE_1(regs, COM_REG_IIR, 0);
    345 	if ((CSR_READ_1(regs, COM_REG_LCR) != LCR_8BITS) ||
    346 	    (CSR_READ_1(regs, COM_REG_IIR) & 0x38))
    347 		return (0);
    348 
    349 	return (1);
    350 }
    351 
    352 int
    353 comprobe1(bus_space_tag_t iot, bus_space_handle_t ioh)
    354 {
    355 	struct com_regs	regs;
    356 
    357 	regs.cr_iot = iot;
    358 	regs.cr_ioh = ioh;
    359 #ifdef	COM_REGMAP
    360 	memcpy(regs.cr_map, com_std_map, sizeof (regs.cr_map));
    361 #endif
    362 
    363 	return com_probe_subr(&regs);
    364 }
    365 
    366 /*
    367  * No locking in this routine; it is only called during attach,
    368  * or with the port already locked.
    369  */
    370 static void
    371 com_enable_debugport(struct com_softc *sc)
    372 {
    373 
    374 	/* Turn on line break interrupt, set carrier. */
    375 	sc->sc_ier = IER_ERXRDY;
    376 	if (sc->sc_type == COM_TYPE_PXA2x0)
    377 		sc->sc_ier |= IER_EUART | IER_ERXTOUT;
    378 	CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, sc->sc_ier);
    379 	SET(sc->sc_mcr, MCR_DTR | MCR_RTS);
    380 	CSR_WRITE_1(&sc->sc_regs, COM_REG_MCR, sc->sc_mcr);
    381 }
    382 
    383 void
    384 com_attach_subr(struct com_softc *sc)
    385 {
    386 	struct com_regs *regsp = &sc->sc_regs;
    387 	struct tty *tp;
    388 #if defined(COM_16650) || defined(COM_16750)
    389 	u_int8_t lcr;
    390 #endif
    391 	const char *fifo_msg = NULL;
    392 	prop_dictionary_t	dict;
    393 	bool is_console = true;
    394 
    395 	aprint_naive("\n");
    396 
    397 	dict = device_properties(sc->sc_dev);
    398 	prop_dictionary_get_bool(dict, "is_console", &is_console);
    399 
    400 	callout_init(&sc->sc_diag_callout, 0);
    401 	mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_HIGH);
    402 
    403 	/* Disable interrupts before configuring the device. */
    404 	if (sc->sc_type == COM_TYPE_PXA2x0)
    405 		sc->sc_ier = IER_EUART;
    406 	else
    407 		sc->sc_ier = 0;
    408 
    409 	CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
    410 
    411 	if (bus_space_is_equal(regsp->cr_iot, comcons_info.regs.cr_iot) &&
    412 	    regsp->cr_iobase == comcons_info.regs.cr_iobase) {
    413 		comconsattached = 1;
    414 
    415 		if (cn_tab == NULL && comcnreattach() != 0) {
    416 			printf("can't re-init serial console @%lx\n",
    417 			    (u_long)comcons_info.regs.cr_iobase);
    418 		}
    419 
    420 #ifdef COM_16750
    421 		/* Use in comintr(). */
    422  		sc->sc_lcr = cflag2lcr(comcons_info.cflag);
    423 #endif
    424 
    425 		/* Make sure the console is always "hardwired". */
    426 		delay(10000);			/* wait for output to finish */
    427 		if (is_console) {
    428 			SET(sc->sc_hwflags, COM_HW_CONSOLE);
    429 		}
    430 
    431 		SET(sc->sc_swflags, TIOCFLAG_SOFTCAR);
    432 	}
    433 
    434 	/* Probe for FIFO */
    435 	switch (sc->sc_type) {
    436 	case COM_TYPE_HAYESP:
    437 		goto fifodone;
    438 
    439 	case COM_TYPE_AU1x00:
    440 		sc->sc_fifolen = 16;
    441 		fifo_msg = "Au1X00 UART, working fifo";
    442 		SET(sc->sc_hwflags, COM_HW_FIFO);
    443 		goto fifodelay;
    444 
    445 	case COM_TYPE_16550_NOERS:
    446 		sc->sc_fifolen = 16;
    447 		fifo_msg = "ns16650, no ERS, working fifo";
    448 		SET(sc->sc_hwflags, COM_HW_FIFO);
    449 		goto fifodelay;
    450 
    451 	case COM_TYPE_OMAP:
    452 		sc->sc_fifolen = 64;
    453 		fifo_msg = "OMAP UART, working fifo";
    454 		SET(sc->sc_hwflags, COM_HW_FIFO);
    455 		goto fifodelay;
    456 	}
    457 
    458 	sc->sc_fifolen = 1;
    459 	/* look for a NS 16550AF UART with FIFOs */
    460 	CSR_WRITE_1(regsp, COM_REG_FIFO,
    461 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_14);
    462 	delay(100);
    463 	if (ISSET(CSR_READ_1(regsp, COM_REG_IIR), IIR_FIFO_MASK)
    464 	    == IIR_FIFO_MASK)
    465 		if (ISSET(CSR_READ_1(regsp, COM_REG_FIFO), FIFO_TRIGGER_14)
    466 		    == FIFO_TRIGGER_14) {
    467 			SET(sc->sc_hwflags, COM_HW_FIFO);
    468 
    469 #ifdef COM_16650
    470 			/*
    471 			 * IIR changes into the EFR if LCR is set to LCR_EERS
    472 			 * on 16650s. We also know IIR != 0 at this point.
    473 			 * Write 0 into the EFR, and read it. If the result
    474 			 * is 0, we have a 16650.
    475 			 *
    476 			 * Older 16650s were broken; the test to detect them
    477 			 * is taken from the Linux driver. Apparently
    478 			 * setting DLAB enable gives access to the EFR on
    479 			 * these chips.
    480 			 */
    481 			lcr = CSR_READ_1(regsp, COM_REG_LCR);
    482 			CSR_WRITE_1(regsp, COM_REG_LCR, LCR_EERS);
    483 			CSR_WRITE_1(regsp, COM_REG_EFR, 0);
    484 			if (CSR_READ_1(regsp, COM_REG_EFR) == 0) {
    485 				CSR_WRITE_1(regsp, COM_REG_LCR, lcr | LCR_DLAB);
    486 				if (CSR_READ_1(regsp, COM_REG_EFR) == 0) {
    487 					CLR(sc->sc_hwflags, COM_HW_FIFO);
    488 					sc->sc_fifolen = 0;
    489 				} else {
    490 					SET(sc->sc_hwflags, COM_HW_FLOW);
    491 					sc->sc_fifolen = 32;
    492 				}
    493 			} else
    494 #endif
    495 				sc->sc_fifolen = 16;
    496 
    497 #ifdef COM_16750
    498 			/*
    499 			 * TL16C750 can enable 64byte FIFO, only when DLAB
    500 			 * is 1.  However, some 16750 may always enable.  For
    501 			 * example, restrictions according to DLAB in a data
    502 			 * sheet for SC16C750 were not described.
    503 			 * Please enable 'options COM_16650', supposing you
    504 			 * use SC16C750.  Probably 32 bytes of FIFO and HW FLOW
    505 			 * should become effective.
    506 			 */
    507 			uint8_t iir1, iir2;
    508 			const uint8_t fcr = FIFO_ENABLE | FIFO_TRIGGER_14;
    509 
    510 			lcr = CSR_READ_1(regsp, COM_REG_LCR);
    511 			CSR_WRITE_1(regsp, COM_REG_LCR, lcr & ~LCR_DLAB);
    512 			CSR_WRITE_1(regsp, COM_REG_FIFO, fcr | FIFO_64B_ENABLE);
    513 			iir1 = CSR_READ_1(regsp, COM_REG_IIR);
    514 			CSR_WRITE_1(regsp, COM_REG_FIFO, fcr);
    515 			CSR_WRITE_1(regsp, COM_REG_LCR, lcr | LCR_DLAB);
    516 			CSR_WRITE_1(regsp, COM_REG_FIFO, fcr | FIFO_64B_ENABLE);
    517 			iir2 = CSR_READ_1(regsp, COM_REG_IIR);
    518 
    519 			CSR_WRITE_1(regsp, COM_REG_LCR, lcr);
    520 
    521 			if (!ISSET(iir1, IIR_64B_FIFO) &&
    522 			    ISSET(iir2, IIR_64B_FIFO)) {
    523 				/* It is TL16C750. */
    524 				sc->sc_fifolen = 64;
    525 				SET(sc->sc_hwflags, COM_HW_AFE);
    526 			} else
    527 				CSR_WRITE_1(regsp, COM_REG_FIFO, fcr);
    528 #endif
    529 
    530 #ifdef COM_16650
    531 			CSR_WRITE_1(regsp, COM_REG_LCR, lcr);
    532 			if (sc->sc_fifolen == 0)
    533 				fifo_msg = "st16650, broken fifo";
    534 			else if (sc->sc_fifolen == 32)
    535 				fifo_msg = "st16650a, working fifo";
    536 			else
    537 #endif
    538 #ifdef COM_16750
    539 			if (sc->sc_fifolen == 64)
    540 				fifo_msg = "tl16c750, working fifo";
    541 			else
    542 #endif
    543 				fifo_msg = "ns16550a, working fifo";
    544 		} else
    545 			fifo_msg = "ns16550, broken fifo";
    546 	else
    547 		fifo_msg = "ns8250 or ns16450, no fifo";
    548 	CSR_WRITE_1(regsp, COM_REG_FIFO, 0);
    549 fifodelay:
    550 	/*
    551 	 * Some chips will clear down both Tx and Rx FIFOs when zero is
    552 	 * written to com_fifo. If this chip is the console, writing zero
    553 	 * results in some of the chip/FIFO description being lost, so delay
    554 	 * printing it until now.
    555 	 */
    556 	delay(10);
    557 	aprint_normal(": %s\n", fifo_msg);
    558 	if (ISSET(sc->sc_hwflags, COM_HW_TXFIFO_DISABLE)) {
    559 		sc->sc_fifolen = 1;
    560 		aprint_normal_dev(sc->sc_dev, "txfifo disabled\n");
    561 	}
    562 
    563 fifodone:
    564 
    565 	tp = tty_alloc();
    566 	tp->t_oproc = comstart;
    567 	tp->t_param = comparam;
    568 	tp->t_hwiflow = comhwiflow;
    569 	tp->t_softc = sc;
    570 
    571 	sc->sc_tty = tp;
    572 	sc->sc_rbuf = malloc(com_rbuf_size << 1, M_DEVBUF, M_NOWAIT);
    573 	sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
    574 	sc->sc_rbavail = com_rbuf_size;
    575 	if (sc->sc_rbuf == NULL) {
    576 		aprint_error_dev(sc->sc_dev,
    577 		    "unable to allocate ring buffer\n");
    578 		return;
    579 	}
    580 	sc->sc_ebuf = sc->sc_rbuf + (com_rbuf_size << 1);
    581 
    582 	tty_attach(tp);
    583 
    584 	if (!ISSET(sc->sc_hwflags, COM_HW_NOIEN))
    585 		SET(sc->sc_mcr, MCR_IENABLE);
    586 
    587 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
    588 		int maj;
    589 
    590 		/* locate the major number */
    591 		maj = cdevsw_lookup_major(&com_cdevsw);
    592 
    593 		tp->t_dev = cn_tab->cn_dev = makedev(maj,
    594 						     device_unit(sc->sc_dev));
    595 
    596 		aprint_normal_dev(sc->sc_dev, "console\n");
    597 	}
    598 
    599 #ifdef KGDB
    600 	/*
    601 	 * Allow kgdb to "take over" this port.  If this is
    602 	 * not the console and is the kgdb device, it has
    603 	 * exclusive use.  If it's the console _and_ the
    604 	 * kgdb device, it doesn't.
    605 	 */
    606 	if (bus_space_is_equal(regsp->cr_iot, comkgdbregs.cr_iot) &&
    607 	    regsp->cr_iobase == comkgdbregs.cr_iobase) {
    608 		if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
    609 			com_kgdb_attached = 1;
    610 
    611 			SET(sc->sc_hwflags, COM_HW_KGDB);
    612 		}
    613 		aprint_normal_dev(sc->sc_dev, "kgdb\n");
    614 	}
    615 #endif
    616 
    617 	sc->sc_si = softint_establish(SOFTINT_SERIAL, comsoft, sc);
    618 
    619 #ifdef RND_COM
    620 	rnd_attach_source(&sc->rnd_source, device_xname(sc->sc_dev),
    621 			  RND_TYPE_TTY, 0);
    622 #endif
    623 
    624 	/* if there are no enable/disable functions, assume the device
    625 	   is always enabled */
    626 	if (!sc->enable)
    627 		sc->enabled = 1;
    628 
    629 	com_config(sc);
    630 
    631 	SET(sc->sc_hwflags, COM_HW_DEV_OK);
    632 }
    633 
    634 void
    635 com_config(struct com_softc *sc)
    636 {
    637 	struct com_regs *regsp = &sc->sc_regs;
    638 
    639 	/* Disable interrupts before configuring the device. */
    640 	if (sc->sc_type == COM_TYPE_PXA2x0)
    641 		sc->sc_ier = IER_EUART;
    642 	else
    643 		sc->sc_ier = 0;
    644 	CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
    645 	(void) CSR_READ_1(regsp, COM_REG_IIR);
    646 
    647 #ifdef COM_HAYESP
    648 	/* Look for a Hayes ESP board. */
    649 	if (sc->sc_type == COM_TYPE_HAYESP) {
    650 
    651 		/* Set 16550 compatibility mode */
    652 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD1,
    653 				  HAYESP_SETMODE);
    654 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
    655 				  HAYESP_MODE_FIFO|HAYESP_MODE_RTS|
    656 				  HAYESP_MODE_SCALE);
    657 
    658 		/* Set RTS/CTS flow control */
    659 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD1,
    660 				  HAYESP_SETFLOWTYPE);
    661 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
    662 				  HAYESP_FLOW_RTS);
    663 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
    664 				  HAYESP_FLOW_CTS);
    665 
    666 		/* Set flow control levels */
    667 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD1,
    668 				  HAYESP_SETRXFLOW);
    669 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
    670 				  HAYESP_HIBYTE(HAYESP_RXHIWMARK));
    671 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
    672 				  HAYESP_LOBYTE(HAYESP_RXHIWMARK));
    673 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
    674 				  HAYESP_HIBYTE(HAYESP_RXLOWMARK));
    675 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
    676 				  HAYESP_LOBYTE(HAYESP_RXLOWMARK));
    677 	}
    678 #endif
    679 
    680 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE|COM_HW_KGDB))
    681 		com_enable_debugport(sc);
    682 }
    683 
    684 #if 0
    685 static int
    686 comcngetc_detached(dev_t dev)
    687 {
    688 	return 0;
    689 }
    690 
    691 static void
    692 comcnputc_detached(dev_t dev, int c)
    693 {
    694 }
    695 #endif
    696 
    697 int
    698 com_detach(device_t self, int flags)
    699 {
    700 	struct com_softc *sc = device_private(self);
    701 	int maj, mn;
    702 
    703 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
    704 		return EBUSY;
    705 
    706 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE) &&
    707 	    (flags & DETACH_SHUTDOWN) != 0)
    708 		return EBUSY;
    709 
    710 	if (sc->disable != NULL && sc->enabled != 0) {
    711 		(*sc->disable)(sc);
    712 		sc->enabled = 0;
    713 	}
    714 
    715 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
    716 		comconsattached = 0;
    717 		cn_tab = NULL;
    718 	}
    719 
    720 	/* locate the major number */
    721 	maj = cdevsw_lookup_major(&com_cdevsw);
    722 
    723 	/* Nuke the vnodes for any open instances. */
    724 	mn = device_unit(self);
    725 	vdevgone(maj, mn, mn, VCHR);
    726 
    727 	mn |= COMDIALOUT_MASK;
    728 	vdevgone(maj, mn, mn, VCHR);
    729 
    730 	if (sc->sc_rbuf == NULL) {
    731 		/*
    732 		 * Ring buffer allocation failed in the com_attach_subr,
    733 		 * only the tty is allocated, and nothing else.
    734 		 */
    735 		tty_free(sc->sc_tty);
    736 		return 0;
    737 	}
    738 
    739 	/* Free the receive buffer. */
    740 	free(sc->sc_rbuf, M_DEVBUF);
    741 
    742 	/* Detach and free the tty. */
    743 	tty_detach(sc->sc_tty);
    744 	tty_free(sc->sc_tty);
    745 
    746 	/* Unhook the soft interrupt handler. */
    747 	softint_disestablish(sc->sc_si);
    748 
    749 #ifdef RND_COM
    750 	/* Unhook the entropy source. */
    751 	rnd_detach_source(&sc->rnd_source);
    752 #endif
    753 	callout_destroy(&sc->sc_diag_callout);
    754 
    755 	/* Destroy the lock. */
    756 	mutex_destroy(&sc->sc_lock);
    757 
    758 	return (0);
    759 }
    760 
    761 void
    762 com_shutdown(struct com_softc *sc)
    763 {
    764 	struct tty *tp = sc->sc_tty;
    765 
    766 	mutex_spin_enter(&sc->sc_lock);
    767 
    768 	/* If we were asserting flow control, then deassert it. */
    769 	SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
    770 	com_hwiflow(sc);
    771 
    772 	/* Clear any break condition set with TIOCSBRK. */
    773 	com_break(sc, 0);
    774 
    775 	/*
    776 	 * Hang up if necessary.  Wait a bit, so the other side has time to
    777 	 * notice even if we immediately open the port again.
    778 	 * Avoid tsleeping above splhigh().
    779 	 */
    780 	if (ISSET(tp->t_cflag, HUPCL)) {
    781 		com_modem(sc, 0);
    782 		mutex_spin_exit(&sc->sc_lock);
    783 		/* XXX will only timeout */
    784 		(void) kpause(ttclos, false, hz, NULL);
    785 		mutex_spin_enter(&sc->sc_lock);
    786 	}
    787 
    788 	/* Turn off interrupts. */
    789 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
    790 		sc->sc_ier = IER_ERXRDY; /* interrupt on break */
    791 		if (sc->sc_type == COM_TYPE_PXA2x0)
    792 			sc->sc_ier |= IER_ERXTOUT;
    793 	} else
    794 		sc->sc_ier = 0;
    795 
    796 	if (sc->sc_type == COM_TYPE_PXA2x0)
    797 		sc->sc_ier |= IER_EUART;
    798 
    799 	CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, sc->sc_ier);
    800 
    801 	mutex_spin_exit(&sc->sc_lock);
    802 
    803 	if (sc->disable) {
    804 #ifdef DIAGNOSTIC
    805 		if (!sc->enabled)
    806 			panic("com_shutdown: not enabled?");
    807 #endif
    808 		(*sc->disable)(sc);
    809 		sc->enabled = 0;
    810 	}
    811 }
    812 
    813 int
    814 comopen(dev_t dev, int flag, int mode, struct lwp *l)
    815 {
    816 	struct com_softc *sc;
    817 	struct tty *tp;
    818 	int s;
    819 	int error;
    820 
    821 	sc = device_lookup_private(&com_cd, COMUNIT(dev));
    822 	if (sc == NULL || !ISSET(sc->sc_hwflags, COM_HW_DEV_OK) ||
    823 		sc->sc_rbuf == NULL)
    824 		return (ENXIO);
    825 
    826 	if (!device_is_active(sc->sc_dev))
    827 		return (ENXIO);
    828 
    829 #ifdef KGDB
    830 	/*
    831 	 * If this is the kgdb port, no other use is permitted.
    832 	 */
    833 	if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
    834 		return (EBUSY);
    835 #endif
    836 
    837 	tp = sc->sc_tty;
    838 
    839 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
    840 		return (EBUSY);
    841 
    842 	s = spltty();
    843 
    844 	/*
    845 	 * Do the following iff this is a first open.
    846 	 */
    847 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
    848 		struct termios t;
    849 
    850 		tp->t_dev = dev;
    851 
    852 		if (sc->enable) {
    853 			if ((*sc->enable)(sc)) {
    854 				splx(s);
    855 				aprint_error_dev(sc->sc_dev,
    856 				    "device enable failed\n");
    857 				return (EIO);
    858 			}
    859 			mutex_spin_enter(&sc->sc_lock);
    860 			sc->enabled = 1;
    861 			com_config(sc);
    862 		} else {
    863 			mutex_spin_enter(&sc->sc_lock);
    864 		}
    865 
    866 		/* Turn on interrupts. */
    867 		sc->sc_ier = IER_ERXRDY | IER_ERLS;
    868 		if (!ISSET(tp->t_cflag, CLOCAL))
    869 			sc->sc_ier |= IER_EMSC;
    870 
    871 		if (sc->sc_type == COM_TYPE_PXA2x0)
    872 			sc->sc_ier |= IER_EUART | IER_ERXTOUT;
    873 		CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, sc->sc_ier);
    874 
    875 		/* Fetch the current modem control status, needed later. */
    876 		sc->sc_msr = CSR_READ_1(&sc->sc_regs, COM_REG_MSR);
    877 
    878 		/* Clear PPS capture state on first open. */
    879 		mutex_spin_enter(&timecounter_lock);
    880 		memset(&sc->sc_pps_state, 0, sizeof(sc->sc_pps_state));
    881 		sc->sc_pps_state.ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR;
    882 		pps_init(&sc->sc_pps_state);
    883 		mutex_spin_exit(&timecounter_lock);
    884 
    885 		mutex_spin_exit(&sc->sc_lock);
    886 
    887 		/*
    888 		 * Initialize the termios status to the defaults.  Add in the
    889 		 * sticky bits from TIOCSFLAGS.
    890 		 */
    891 		if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
    892 			t.c_ospeed = comcons_info.rate;
    893 			t.c_cflag = comcons_info.cflag;
    894 		} else {
    895 			t.c_ospeed = TTYDEF_SPEED;
    896 			t.c_cflag = TTYDEF_CFLAG;
    897 		}
    898 		t.c_ispeed = t.c_ospeed;
    899 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
    900 			SET(t.c_cflag, CLOCAL);
    901 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
    902 			SET(t.c_cflag, CRTSCTS);
    903 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
    904 			SET(t.c_cflag, MDMBUF);
    905 		/* Make sure comparam() will do something. */
    906 		tp->t_ospeed = 0;
    907 		(void) comparam(tp, &t);
    908 		tp->t_iflag = TTYDEF_IFLAG;
    909 		tp->t_oflag = TTYDEF_OFLAG;
    910 		tp->t_lflag = TTYDEF_LFLAG;
    911 		ttychars(tp);
    912 		ttsetwater(tp);
    913 
    914 		mutex_spin_enter(&sc->sc_lock);
    915 
    916 		/*
    917 		 * Turn on DTR.  We must always do this, even if carrier is not
    918 		 * present, because otherwise we'd have to use TIOCSDTR
    919 		 * immediately after setting CLOCAL, which applications do not
    920 		 * expect.  We always assert DTR while the device is open
    921 		 * unless explicitly requested to deassert it.
    922 		 */
    923 		com_modem(sc, 1);
    924 
    925 		/* Clear the input ring, and unblock. */
    926 		sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
    927 		sc->sc_rbavail = com_rbuf_size;
    928 		com_iflush(sc);
    929 		CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
    930 		com_hwiflow(sc);
    931 
    932 #ifdef COM_DEBUG
    933 		if (com_debug)
    934 			comstatus(sc, "comopen  ");
    935 #endif
    936 
    937 		mutex_spin_exit(&sc->sc_lock);
    938 	}
    939 
    940 	splx(s);
    941 
    942 	error = ttyopen(tp, COMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
    943 	if (error)
    944 		goto bad;
    945 
    946 	error = (*tp->t_linesw->l_open)(dev, tp);
    947 	if (error)
    948 		goto bad;
    949 
    950 	return (0);
    951 
    952 bad:
    953 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
    954 		/*
    955 		 * We failed to open the device, and nobody else had it opened.
    956 		 * Clean up the state as appropriate.
    957 		 */
    958 		com_shutdown(sc);
    959 	}
    960 
    961 	return (error);
    962 }
    963 
    964 int
    965 comclose(dev_t dev, int flag, int mode, struct lwp *l)
    966 {
    967 	struct com_softc *sc =
    968 	    device_lookup_private(&com_cd, COMUNIT(dev));
    969 	struct tty *tp = sc->sc_tty;
    970 
    971 	/* XXX This is for cons.c. */
    972 	if (!ISSET(tp->t_state, TS_ISOPEN))
    973 		return (0);
    974 
    975 	(*tp->t_linesw->l_close)(tp, flag);
    976 	ttyclose(tp);
    977 
    978 	if (COM_ISALIVE(sc) == 0)
    979 		return (0);
    980 
    981 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
    982 		/*
    983 		 * Although we got a last close, the device may still be in
    984 		 * use; e.g. if this was the dialout node, and there are still
    985 		 * processes waiting for carrier on the non-dialout node.
    986 		 */
    987 		com_shutdown(sc);
    988 	}
    989 
    990 	return (0);
    991 }
    992 
    993 int
    994 comread(dev_t dev, struct uio *uio, int flag)
    995 {
    996 	struct com_softc *sc =
    997 	    device_lookup_private(&com_cd, COMUNIT(dev));
    998 	struct tty *tp = sc->sc_tty;
    999 
   1000 	if (COM_ISALIVE(sc) == 0)
   1001 		return (EIO);
   1002 
   1003 	return ((*tp->t_linesw->l_read)(tp, uio, flag));
   1004 }
   1005 
   1006 int
   1007 comwrite(dev_t dev, struct uio *uio, int flag)
   1008 {
   1009 	struct com_softc *sc =
   1010 	    device_lookup_private(&com_cd, COMUNIT(dev));
   1011 	struct tty *tp = sc->sc_tty;
   1012 
   1013 	if (COM_ISALIVE(sc) == 0)
   1014 		return (EIO);
   1015 
   1016 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
   1017 }
   1018 
   1019 int
   1020 compoll(dev_t dev, int events, struct lwp *l)
   1021 {
   1022 	struct com_softc *sc =
   1023 	    device_lookup_private(&com_cd, COMUNIT(dev));
   1024 	struct tty *tp = sc->sc_tty;
   1025 
   1026 	if (COM_ISALIVE(sc) == 0)
   1027 		return (POLLHUP);
   1028 
   1029 	return ((*tp->t_linesw->l_poll)(tp, events, l));
   1030 }
   1031 
   1032 struct tty *
   1033 comtty(dev_t dev)
   1034 {
   1035 	struct com_softc *sc =
   1036 	    device_lookup_private(&com_cd, COMUNIT(dev));
   1037 	struct tty *tp = sc->sc_tty;
   1038 
   1039 	return (tp);
   1040 }
   1041 
   1042 int
   1043 comioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
   1044 {
   1045 	struct com_softc *sc;
   1046 	struct tty *tp;
   1047 	int error;
   1048 
   1049 	sc = device_lookup_private(&com_cd, COMUNIT(dev));
   1050 	if (sc == NULL)
   1051 		return ENXIO;
   1052 	if (COM_ISALIVE(sc) == 0)
   1053 		return (EIO);
   1054 
   1055 	tp = sc->sc_tty;
   1056 
   1057 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
   1058 	if (error != EPASSTHROUGH)
   1059 		return (error);
   1060 
   1061 	error = ttioctl(tp, cmd, data, flag, l);
   1062 	if (error != EPASSTHROUGH)
   1063 		return (error);
   1064 
   1065 	error = 0;
   1066 	switch (cmd) {
   1067 	case TIOCSFLAGS:
   1068 		error = kauth_authorize_device_tty(l->l_cred,
   1069 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
   1070 		break;
   1071 	default:
   1072 		/* nothing */
   1073 		break;
   1074 	}
   1075 	if (error) {
   1076 		return error;
   1077 	}
   1078 
   1079 	mutex_spin_enter(&sc->sc_lock);
   1080 
   1081 	switch (cmd) {
   1082 	case TIOCSBRK:
   1083 		com_break(sc, 1);
   1084 		break;
   1085 
   1086 	case TIOCCBRK:
   1087 		com_break(sc, 0);
   1088 		break;
   1089 
   1090 	case TIOCSDTR:
   1091 		com_modem(sc, 1);
   1092 		break;
   1093 
   1094 	case TIOCCDTR:
   1095 		com_modem(sc, 0);
   1096 		break;
   1097 
   1098 	case TIOCGFLAGS:
   1099 		*(int *)data = sc->sc_swflags;
   1100 		break;
   1101 
   1102 	case TIOCSFLAGS:
   1103 		sc->sc_swflags = *(int *)data;
   1104 		break;
   1105 
   1106 	case TIOCMSET:
   1107 	case TIOCMBIS:
   1108 	case TIOCMBIC:
   1109 		tiocm_to_com(sc, cmd, *(int *)data);
   1110 		break;
   1111 
   1112 	case TIOCMGET:
   1113 		*(int *)data = com_to_tiocm(sc);
   1114 		break;
   1115 
   1116 	case PPS_IOC_CREATE:
   1117 	case PPS_IOC_DESTROY:
   1118 	case PPS_IOC_GETPARAMS:
   1119 	case PPS_IOC_SETPARAMS:
   1120 	case PPS_IOC_GETCAP:
   1121 	case PPS_IOC_FETCH:
   1122 #ifdef PPS_SYNC
   1123 	case PPS_IOC_KCBIND:
   1124 #endif
   1125 		mutex_spin_enter(&timecounter_lock);
   1126 		error = pps_ioctl(cmd, data, &sc->sc_pps_state);
   1127 		mutex_spin_exit(&timecounter_lock);
   1128 		break;
   1129 
   1130 	case TIOCDCDTIMESTAMP:	/* XXX old, overloaded  API used by xntpd v3 */
   1131 		mutex_spin_enter(&timecounter_lock);
   1132 #ifndef PPS_TRAILING_EDGE
   1133 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
   1134 		    &sc->sc_pps_state.ppsinfo.assert_timestamp);
   1135 #else
   1136 		TIMESPEC_TO_TIMEVAL((struct timeval *)data,
   1137 		    &sc->sc_pps_state.ppsinfo.clear_timestamp);
   1138 #endif
   1139 		mutex_spin_exit(&timecounter_lock);
   1140 		break;
   1141 
   1142 	default:
   1143 		error = EPASSTHROUGH;
   1144 		break;
   1145 	}
   1146 
   1147 	mutex_spin_exit(&sc->sc_lock);
   1148 
   1149 #ifdef COM_DEBUG
   1150 	if (com_debug)
   1151 		comstatus(sc, "comioctl ");
   1152 #endif
   1153 
   1154 	return (error);
   1155 }
   1156 
   1157 integrate void
   1158 com_schedrx(struct com_softc *sc)
   1159 {
   1160 
   1161 	sc->sc_rx_ready = 1;
   1162 
   1163 	/* Wake up the poller. */
   1164 	softint_schedule(sc->sc_si);
   1165 }
   1166 
   1167 void
   1168 com_break(struct com_softc *sc, int onoff)
   1169 {
   1170 
   1171 	if (onoff)
   1172 		SET(sc->sc_lcr, LCR_SBREAK);
   1173 	else
   1174 		CLR(sc->sc_lcr, LCR_SBREAK);
   1175 
   1176 	if (!sc->sc_heldchange) {
   1177 		if (sc->sc_tx_busy) {
   1178 			sc->sc_heldtbc = sc->sc_tbc;
   1179 			sc->sc_tbc = 0;
   1180 			sc->sc_heldchange = 1;
   1181 		} else
   1182 			com_loadchannelregs(sc);
   1183 	}
   1184 }
   1185 
   1186 void
   1187 com_modem(struct com_softc *sc, int onoff)
   1188 {
   1189 
   1190 	if (sc->sc_mcr_dtr == 0)
   1191 		return;
   1192 
   1193 	if (onoff)
   1194 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
   1195 	else
   1196 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
   1197 
   1198 	if (!sc->sc_heldchange) {
   1199 		if (sc->sc_tx_busy) {
   1200 			sc->sc_heldtbc = sc->sc_tbc;
   1201 			sc->sc_tbc = 0;
   1202 			sc->sc_heldchange = 1;
   1203 		} else
   1204 			com_loadchannelregs(sc);
   1205 	}
   1206 }
   1207 
   1208 void
   1209 tiocm_to_com(struct com_softc *sc, u_long how, int ttybits)
   1210 {
   1211 	u_char combits;
   1212 
   1213 	combits = 0;
   1214 	if (ISSET(ttybits, TIOCM_DTR))
   1215 		SET(combits, MCR_DTR);
   1216 	if (ISSET(ttybits, TIOCM_RTS))
   1217 		SET(combits, MCR_RTS);
   1218 
   1219 	switch (how) {
   1220 	case TIOCMBIC:
   1221 		CLR(sc->sc_mcr, combits);
   1222 		break;
   1223 
   1224 	case TIOCMBIS:
   1225 		SET(sc->sc_mcr, combits);
   1226 		break;
   1227 
   1228 	case TIOCMSET:
   1229 		CLR(sc->sc_mcr, MCR_DTR | MCR_RTS);
   1230 		SET(sc->sc_mcr, combits);
   1231 		break;
   1232 	}
   1233 
   1234 	if (!sc->sc_heldchange) {
   1235 		if (sc->sc_tx_busy) {
   1236 			sc->sc_heldtbc = sc->sc_tbc;
   1237 			sc->sc_tbc = 0;
   1238 			sc->sc_heldchange = 1;
   1239 		} else
   1240 			com_loadchannelregs(sc);
   1241 	}
   1242 }
   1243 
   1244 int
   1245 com_to_tiocm(struct com_softc *sc)
   1246 {
   1247 	u_char combits;
   1248 	int ttybits = 0;
   1249 
   1250 	combits = sc->sc_mcr;
   1251 	if (ISSET(combits, MCR_DTR))
   1252 		SET(ttybits, TIOCM_DTR);
   1253 	if (ISSET(combits, MCR_RTS))
   1254 		SET(ttybits, TIOCM_RTS);
   1255 
   1256 	combits = sc->sc_msr;
   1257 	if (ISSET(combits, MSR_DCD))
   1258 		SET(ttybits, TIOCM_CD);
   1259 	if (ISSET(combits, MSR_CTS))
   1260 		SET(ttybits, TIOCM_CTS);
   1261 	if (ISSET(combits, MSR_DSR))
   1262 		SET(ttybits, TIOCM_DSR);
   1263 	if (ISSET(combits, MSR_RI | MSR_TERI))
   1264 		SET(ttybits, TIOCM_RI);
   1265 
   1266 	if (ISSET(sc->sc_ier, IER_ERXRDY | IER_ETXRDY | IER_ERLS | IER_EMSC))
   1267 		SET(ttybits, TIOCM_LE);
   1268 
   1269 	return (ttybits);
   1270 }
   1271 
   1272 static u_char
   1273 cflag2lcr(tcflag_t cflag)
   1274 {
   1275 	u_char lcr = 0;
   1276 
   1277 	switch (ISSET(cflag, CSIZE)) {
   1278 	case CS5:
   1279 		SET(lcr, LCR_5BITS);
   1280 		break;
   1281 	case CS6:
   1282 		SET(lcr, LCR_6BITS);
   1283 		break;
   1284 	case CS7:
   1285 		SET(lcr, LCR_7BITS);
   1286 		break;
   1287 	case CS8:
   1288 		SET(lcr, LCR_8BITS);
   1289 		break;
   1290 	}
   1291 	if (ISSET(cflag, PARENB)) {
   1292 		SET(lcr, LCR_PENAB);
   1293 		if (!ISSET(cflag, PARODD))
   1294 			SET(lcr, LCR_PEVEN);
   1295 	}
   1296 	if (ISSET(cflag, CSTOPB))
   1297 		SET(lcr, LCR_STOPB);
   1298 
   1299 	return (lcr);
   1300 }
   1301 
   1302 int
   1303 comparam(struct tty *tp, struct termios *t)
   1304 {
   1305 	struct com_softc *sc =
   1306 	    device_lookup_private(&com_cd, COMUNIT(tp->t_dev));
   1307 	int ospeed;
   1308 	u_char lcr;
   1309 
   1310 	if (COM_ISALIVE(sc) == 0)
   1311 		return (EIO);
   1312 
   1313 #ifdef COM_HAYESP
   1314 	if (sc->sc_type == COM_TYPE_HAYESP) {
   1315 		int prescaler, speed;
   1316 
   1317 		/*
   1318 		 * Calculate UART clock prescaler.  It should be in
   1319 		 * range of 0 .. 3.
   1320 		 */
   1321 		for (prescaler = 0, speed = t->c_ospeed; prescaler < 4;
   1322 		    prescaler++, speed /= 2)
   1323 			if ((ospeed = comspeed(speed, sc->sc_frequency,
   1324 					       sc->sc_type)) > 0)
   1325 				break;
   1326 
   1327 		if (prescaler == 4)
   1328 			return (EINVAL);
   1329 		sc->sc_prescaler = prescaler;
   1330 	} else
   1331 #endif
   1332 	ospeed = comspeed(t->c_ospeed, sc->sc_frequency, sc->sc_type);
   1333 
   1334 	/* Check requested parameters. */
   1335 	if (ospeed < 0)
   1336 		return (EINVAL);
   1337 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
   1338 		return (EINVAL);
   1339 
   1340 	/*
   1341 	 * For the console, always force CLOCAL and !HUPCL, so that the port
   1342 	 * is always active.
   1343 	 */
   1344 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
   1345 	    ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
   1346 		SET(t->c_cflag, CLOCAL);
   1347 		CLR(t->c_cflag, HUPCL);
   1348 	}
   1349 
   1350 	/*
   1351 	 * If there were no changes, don't do anything.  This avoids dropping
   1352 	 * input and improves performance when all we did was frob things like
   1353 	 * VMIN and VTIME.
   1354 	 */
   1355 	if (tp->t_ospeed == t->c_ospeed &&
   1356 	    tp->t_cflag == t->c_cflag)
   1357 		return (0);
   1358 
   1359 	lcr = ISSET(sc->sc_lcr, LCR_SBREAK) | cflag2lcr(t->c_cflag);
   1360 
   1361 	mutex_spin_enter(&sc->sc_lock);
   1362 
   1363 	sc->sc_lcr = lcr;
   1364 
   1365 	/*
   1366 	 * If we're not in a mode that assumes a connection is present, then
   1367 	 * ignore carrier changes.
   1368 	 */
   1369 	if (ISSET(t->c_cflag, CLOCAL | MDMBUF))
   1370 		sc->sc_msr_dcd = 0;
   1371 	else
   1372 		sc->sc_msr_dcd = MSR_DCD;
   1373 	/*
   1374 	 * Set the flow control pins depending on the current flow control
   1375 	 * mode.
   1376 	 */
   1377 	if (ISSET(t->c_cflag, CRTSCTS)) {
   1378 		sc->sc_mcr_dtr = MCR_DTR;
   1379 		sc->sc_mcr_rts = MCR_RTS;
   1380 		sc->sc_msr_cts = MSR_CTS;
   1381 		if (ISSET(sc->sc_hwflags, COM_HW_AFE)) {
   1382 			SET(sc->sc_mcr, MCR_AFE);
   1383 		} else {
   1384 			sc->sc_efr = EFR_AUTORTS | EFR_AUTOCTS;
   1385 		}
   1386 	} else if (ISSET(t->c_cflag, MDMBUF)) {
   1387 		/*
   1388 		 * For DTR/DCD flow control, make sure we don't toggle DTR for
   1389 		 * carrier detection.
   1390 		 */
   1391 		sc->sc_mcr_dtr = 0;
   1392 		sc->sc_mcr_rts = MCR_DTR;
   1393 		sc->sc_msr_cts = MSR_DCD;
   1394 		if (ISSET(sc->sc_hwflags, COM_HW_AFE)) {
   1395 			CLR(sc->sc_mcr, MCR_AFE);
   1396 		} else {
   1397 			sc->sc_efr = 0;
   1398 		}
   1399 	} else {
   1400 		/*
   1401 		 * If no flow control, then always set RTS.  This will make
   1402 		 * the other side happy if it mistakenly thinks we're doing
   1403 		 * RTS/CTS flow control.
   1404 		 */
   1405 		sc->sc_mcr_dtr = MCR_DTR | MCR_RTS;
   1406 		sc->sc_mcr_rts = 0;
   1407 		sc->sc_msr_cts = 0;
   1408 		if (ISSET(sc->sc_hwflags, COM_HW_AFE)) {
   1409 			CLR(sc->sc_mcr, MCR_AFE);
   1410 		} else {
   1411 			sc->sc_efr = 0;
   1412 		}
   1413 		if (ISSET(sc->sc_mcr, MCR_DTR))
   1414 			SET(sc->sc_mcr, MCR_RTS);
   1415 		else
   1416 			CLR(sc->sc_mcr, MCR_RTS);
   1417 	}
   1418 	sc->sc_msr_mask = sc->sc_msr_cts | sc->sc_msr_dcd;
   1419 
   1420 #if 0
   1421 	if (ospeed == 0)
   1422 		CLR(sc->sc_mcr, sc->sc_mcr_dtr);
   1423 	else
   1424 		SET(sc->sc_mcr, sc->sc_mcr_dtr);
   1425 #endif
   1426 
   1427 	sc->sc_dlbl = ospeed;
   1428 	sc->sc_dlbh = ospeed >> 8;
   1429 
   1430 	/*
   1431 	 * Set the FIFO threshold based on the receive speed.
   1432 	 *
   1433 	 *  * If it's a low speed, it's probably a mouse or some other
   1434 	 *    interactive device, so set the threshold low.
   1435 	 *  * If it's a high speed, trim the trigger level down to prevent
   1436 	 *    overflows.
   1437 	 *  * Otherwise set it a bit higher.
   1438 	 */
   1439 	if (sc->sc_type == COM_TYPE_HAYESP)
   1440 		sc->sc_fifo = FIFO_DMA_MODE | FIFO_ENABLE | FIFO_TRIGGER_8;
   1441 	else if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) {
   1442 		if (t->c_ospeed <= 1200)
   1443 			sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_1;
   1444 		else if (t->c_ospeed <= 38400)
   1445 			sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_8;
   1446 		else
   1447 			sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_4;
   1448 	} else
   1449 		sc->sc_fifo = 0;
   1450 
   1451 	/* And copy to tty. */
   1452 	tp->t_ispeed = t->c_ospeed;
   1453 	tp->t_ospeed = t->c_ospeed;
   1454 	tp->t_cflag = t->c_cflag;
   1455 
   1456 	if (!sc->sc_heldchange) {
   1457 		if (sc->sc_tx_busy) {
   1458 			sc->sc_heldtbc = sc->sc_tbc;
   1459 			sc->sc_tbc = 0;
   1460 			sc->sc_heldchange = 1;
   1461 		} else
   1462 			com_loadchannelregs(sc);
   1463 	}
   1464 
   1465 	if (!ISSET(t->c_cflag, CHWFLOW)) {
   1466 		/* Disable the high water mark. */
   1467 		sc->sc_r_hiwat = 0;
   1468 		sc->sc_r_lowat = 0;
   1469 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
   1470 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
   1471 			com_schedrx(sc);
   1472 		}
   1473 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
   1474 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
   1475 			com_hwiflow(sc);
   1476 		}
   1477 	} else {
   1478 		sc->sc_r_hiwat = com_rbuf_hiwat;
   1479 		sc->sc_r_lowat = com_rbuf_lowat;
   1480 	}
   1481 
   1482 	mutex_spin_exit(&sc->sc_lock);
   1483 
   1484 	/*
   1485 	 * Update the tty layer's idea of the carrier bit, in case we changed
   1486 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
   1487 	 * explicit request.
   1488 	 */
   1489 	(void) (*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_msr, MSR_DCD));
   1490 
   1491 #ifdef COM_DEBUG
   1492 	if (com_debug)
   1493 		comstatus(sc, "comparam ");
   1494 #endif
   1495 
   1496 	if (!ISSET(t->c_cflag, CHWFLOW)) {
   1497 		if (sc->sc_tx_stopped) {
   1498 			sc->sc_tx_stopped = 0;
   1499 			comstart(tp);
   1500 		}
   1501 	}
   1502 
   1503 	return (0);
   1504 }
   1505 
   1506 void
   1507 com_iflush(struct com_softc *sc)
   1508 {
   1509 	struct com_regs	*regsp = &sc->sc_regs;
   1510 #ifdef DIAGNOSTIC
   1511 	int reg;
   1512 #endif
   1513 	int timo;
   1514 
   1515 #ifdef DIAGNOSTIC
   1516 	reg = 0xffff;
   1517 #endif
   1518 	timo = 50000;
   1519 	/* flush any pending I/O */
   1520 	while (ISSET(CSR_READ_1(regsp, COM_REG_LSR), LSR_RXRDY)
   1521 	    && --timo)
   1522 #ifdef DIAGNOSTIC
   1523 		reg =
   1524 #else
   1525 		    (void)
   1526 #endif
   1527 		    CSR_READ_1(regsp, COM_REG_RXDATA);
   1528 #ifdef DIAGNOSTIC
   1529 	if (!timo)
   1530 		aprint_error_dev(sc->sc_dev, "com_iflush timeout %02x\n", reg);
   1531 #endif
   1532 
   1533 #ifdef COM_16750
   1534 	uint8_t fifo;
   1535 	/*
   1536 	 * Reset all Rx/Tx FIFO, preserve current FIFO length.
   1537 	 * This should prevent triggering busy interrupt while
   1538 	 * manipulating divisors.
   1539 	 */
   1540 	fifo = CSR_READ_1(regsp, COM_REG_FIFO) & (FIFO_TRIGGER_1 |
   1541 	    FIFO_TRIGGER_4 | FIFO_TRIGGER_8 | FIFO_TRIGGER_14);
   1542 	CSR_WRITE_1(regsp, COM_REG_FIFO, fifo | FIFO_ENABLE | FIFO_RCV_RST |
   1543 	    FIFO_XMT_RST);
   1544 	delay(100);
   1545 #endif
   1546 }
   1547 
   1548 void
   1549 com_loadchannelregs(struct com_softc *sc)
   1550 {
   1551 	struct com_regs *regsp = &sc->sc_regs;
   1552 
   1553 	/* XXXXX necessary? */
   1554 	com_iflush(sc);
   1555 
   1556 	if (sc->sc_type == COM_TYPE_PXA2x0)
   1557 		CSR_WRITE_1(regsp, COM_REG_IER, IER_EUART);
   1558 	else
   1559 		CSR_WRITE_1(regsp, COM_REG_IER, 0);
   1560 
   1561 	if (sc->sc_type == COM_TYPE_OMAP) {
   1562 		/* disable before changing settings */
   1563 		CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_DISABLE);
   1564 	}
   1565 
   1566 	if (ISSET(sc->sc_hwflags, COM_HW_FLOW)) {
   1567 		KASSERT(sc->sc_type != COM_TYPE_AU1x00);
   1568 		KASSERT(sc->sc_type != COM_TYPE_16550_NOERS);
   1569 		/* no EFR on alchemy */
   1570 		CSR_WRITE_1(regsp, COM_REG_LCR, LCR_EERS);
   1571 		CSR_WRITE_1(regsp, COM_REG_EFR, sc->sc_efr);
   1572 	}
   1573 	if (sc->sc_type == COM_TYPE_AU1x00) {
   1574 		/* alchemy has single separate 16-bit clock divisor register */
   1575 		CSR_WRITE_2(regsp, COM_REG_DLBL, sc->sc_dlbl +
   1576 		    (sc->sc_dlbh << 8));
   1577 	} else {
   1578 		CSR_WRITE_1(regsp, COM_REG_LCR, sc->sc_lcr | LCR_DLAB);
   1579 		CSR_WRITE_1(regsp, COM_REG_DLBL, sc->sc_dlbl);
   1580 		CSR_WRITE_1(regsp, COM_REG_DLBH, sc->sc_dlbh);
   1581 	}
   1582 	CSR_WRITE_1(regsp, COM_REG_LCR, sc->sc_lcr);
   1583 	CSR_WRITE_1(regsp, COM_REG_MCR, sc->sc_mcr_active = sc->sc_mcr);
   1584 	CSR_WRITE_1(regsp, COM_REG_FIFO, sc->sc_fifo);
   1585 #ifdef COM_HAYESP
   1586 	if (sc->sc_type == COM_TYPE_HAYESP) {
   1587 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD1,
   1588 		    HAYESP_SETPRESCALER);
   1589 		bus_space_write_1(regsp->cr_iot, sc->sc_hayespioh, HAYESP_CMD2,
   1590 		    sc->sc_prescaler);
   1591 	}
   1592 #endif
   1593 	if (sc->sc_type == COM_TYPE_OMAP) {
   1594 		/* setup the fifos.  the FCR value is not used as long
   1595 		   as SCR[6] and SCR[7] are 0, which they are at reset
   1596 		   and we never touch the SCR register */
   1597 		uint8_t rx_fifo_trig = 40;
   1598 		uint8_t tx_fifo_trig = 60;
   1599 		uint8_t rx_start = 8;
   1600 		uint8_t rx_halt = 60;
   1601 		uint8_t tlr_value = ((rx_fifo_trig>>2) << 4) | (tx_fifo_trig>>2);
   1602 		uint8_t tcr_value = ((rx_start>>2) << 4) | (rx_halt>>2);
   1603 
   1604 		/* enable access to TCR & TLR */
   1605 		CSR_WRITE_1(regsp, COM_REG_MCR, sc->sc_mcr | MCR_TCR_TLR);
   1606 
   1607 		/* write tcr and tlr values */
   1608 		CSR_WRITE_1(regsp, COM_REG_TLR, tlr_value);
   1609 		CSR_WRITE_1(regsp, COM_REG_TCR, tcr_value);
   1610 
   1611 		/* disable access to TCR & TLR */
   1612 		CSR_WRITE_1(regsp, COM_REG_MCR, sc->sc_mcr);
   1613 
   1614 		/* enable again, but mode is based on speed */
   1615 		if (sc->sc_tty->t_termios.c_ospeed > 230400) {
   1616 			CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_UART_13X);
   1617 		} else {
   1618 			CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_UART_16X);
   1619 		}
   1620 	}
   1621 
   1622 	CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
   1623 }
   1624 
   1625 int
   1626 comhwiflow(struct tty *tp, int block)
   1627 {
   1628 	struct com_softc *sc =
   1629 	    device_lookup_private(&com_cd, COMUNIT(tp->t_dev));
   1630 
   1631 	if (COM_ISALIVE(sc) == 0)
   1632 		return (0);
   1633 
   1634 	if (sc->sc_mcr_rts == 0)
   1635 		return (0);
   1636 
   1637 	mutex_spin_enter(&sc->sc_lock);
   1638 
   1639 	if (block) {
   1640 		if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
   1641 			SET(sc->sc_rx_flags, RX_TTY_BLOCKED);
   1642 			com_hwiflow(sc);
   1643 		}
   1644 	} else {
   1645 		if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
   1646 			CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
   1647 			com_schedrx(sc);
   1648 		}
   1649 		if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
   1650 			CLR(sc->sc_rx_flags, RX_TTY_BLOCKED);
   1651 			com_hwiflow(sc);
   1652 		}
   1653 	}
   1654 
   1655 	mutex_spin_exit(&sc->sc_lock);
   1656 	return (1);
   1657 }
   1658 
   1659 /*
   1660  * (un)block input via hw flowcontrol
   1661  */
   1662 void
   1663 com_hwiflow(struct com_softc *sc)
   1664 {
   1665 	struct com_regs *regsp= &sc->sc_regs;
   1666 
   1667 	if (sc->sc_mcr_rts == 0)
   1668 		return;
   1669 
   1670 	if (ISSET(sc->sc_rx_flags, RX_ANY_BLOCK)) {
   1671 		CLR(sc->sc_mcr, sc->sc_mcr_rts);
   1672 		CLR(sc->sc_mcr_active, sc->sc_mcr_rts);
   1673 	} else {
   1674 		SET(sc->sc_mcr, sc->sc_mcr_rts);
   1675 		SET(sc->sc_mcr_active, sc->sc_mcr_rts);
   1676 	}
   1677 	CSR_WRITE_1(regsp, COM_REG_MCR, sc->sc_mcr_active);
   1678 }
   1679 
   1680 
   1681 void
   1682 comstart(struct tty *tp)
   1683 {
   1684 	struct com_softc *sc =
   1685 	    device_lookup_private(&com_cd, COMUNIT(tp->t_dev));
   1686 	struct com_regs *regsp = &sc->sc_regs;
   1687 	int s;
   1688 
   1689 	if (COM_ISALIVE(sc) == 0)
   1690 		return;
   1691 
   1692 	s = spltty();
   1693 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
   1694 		goto out;
   1695 	if (sc->sc_tx_stopped)
   1696 		goto out;
   1697 	if (!ttypull(tp))
   1698 		goto out;
   1699 
   1700 	/* Grab the first contiguous region of buffer space. */
   1701 	{
   1702 		u_char *tba;
   1703 		int tbc;
   1704 
   1705 		tba = tp->t_outq.c_cf;
   1706 		tbc = ndqb(&tp->t_outq, 0);
   1707 
   1708 		mutex_spin_enter(&sc->sc_lock);
   1709 
   1710 		sc->sc_tba = tba;
   1711 		sc->sc_tbc = tbc;
   1712 	}
   1713 
   1714 	SET(tp->t_state, TS_BUSY);
   1715 	sc->sc_tx_busy = 1;
   1716 
   1717 	/* Enable transmit completion interrupts if necessary. */
   1718 	if (!ISSET(sc->sc_ier, IER_ETXRDY)) {
   1719 		SET(sc->sc_ier, IER_ETXRDY);
   1720 		CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
   1721 	}
   1722 
   1723 	/* Output the first chunk of the contiguous buffer. */
   1724 	if (!ISSET(sc->sc_hwflags, COM_HW_NO_TXPRELOAD)) {
   1725 		u_int n;
   1726 
   1727 		n = sc->sc_tbc;
   1728 		if (n > sc->sc_fifolen)
   1729 			n = sc->sc_fifolen;
   1730 		CSR_WRITE_MULTI(regsp, COM_REG_TXDATA, sc->sc_tba, n);
   1731 		sc->sc_tbc -= n;
   1732 		sc->sc_tba += n;
   1733 	}
   1734 
   1735 	mutex_spin_exit(&sc->sc_lock);
   1736 out:
   1737 	splx(s);
   1738 	return;
   1739 }
   1740 
   1741 /*
   1742  * Stop output on a line.
   1743  */
   1744 void
   1745 comstop(struct tty *tp, int flag)
   1746 {
   1747 	struct com_softc *sc =
   1748 	    device_lookup_private(&com_cd, COMUNIT(tp->t_dev));
   1749 
   1750 	mutex_spin_enter(&sc->sc_lock);
   1751 	if (ISSET(tp->t_state, TS_BUSY)) {
   1752 		/* Stop transmitting at the next chunk. */
   1753 		sc->sc_tbc = 0;
   1754 		sc->sc_heldtbc = 0;
   1755 		if (!ISSET(tp->t_state, TS_TTSTOP))
   1756 			SET(tp->t_state, TS_FLUSH);
   1757 	}
   1758 	mutex_spin_exit(&sc->sc_lock);
   1759 }
   1760 
   1761 void
   1762 comdiag(void *arg)
   1763 {
   1764 	struct com_softc *sc = arg;
   1765 	int overflows, floods;
   1766 
   1767 	mutex_spin_enter(&sc->sc_lock);
   1768 	overflows = sc->sc_overflows;
   1769 	sc->sc_overflows = 0;
   1770 	floods = sc->sc_floods;
   1771 	sc->sc_floods = 0;
   1772 	sc->sc_errors = 0;
   1773 	mutex_spin_exit(&sc->sc_lock);
   1774 
   1775 	log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n",
   1776 	    device_xname(sc->sc_dev),
   1777 	    overflows, overflows == 1 ? "" : "s",
   1778 	    floods, floods == 1 ? "" : "s");
   1779 }
   1780 
   1781 integrate void
   1782 com_rxsoft(struct com_softc *sc, struct tty *tp)
   1783 {
   1784 	int (*rint)(int, struct tty *) = tp->t_linesw->l_rint;
   1785 	u_char *get, *end;
   1786 	u_int cc, scc;
   1787 	u_char lsr;
   1788 	int code;
   1789 
   1790 	end = sc->sc_ebuf;
   1791 	get = sc->sc_rbget;
   1792 	scc = cc = com_rbuf_size - sc->sc_rbavail;
   1793 
   1794 	if (cc == com_rbuf_size) {
   1795 		sc->sc_floods++;
   1796 		if (sc->sc_errors++ == 0)
   1797 			callout_reset(&sc->sc_diag_callout, 60 * hz,
   1798 			    comdiag, sc);
   1799 	}
   1800 
   1801 	/* If not yet open, drop the entire buffer content here */
   1802 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
   1803 		get += cc << 1;
   1804 		if (get >= end)
   1805 			get -= com_rbuf_size << 1;
   1806 		cc = 0;
   1807 	}
   1808 	while (cc) {
   1809 		code = get[0];
   1810 		lsr = get[1];
   1811 		if (ISSET(lsr, LSR_OE | LSR_BI | LSR_FE | LSR_PE)) {
   1812 			if (ISSET(lsr, LSR_OE)) {
   1813 				sc->sc_overflows++;
   1814 				if (sc->sc_errors++ == 0)
   1815 					callout_reset(&sc->sc_diag_callout,
   1816 					    60 * hz, comdiag, sc);
   1817 			}
   1818 			if (ISSET(lsr, LSR_BI | LSR_FE))
   1819 				SET(code, TTY_FE);
   1820 			if (ISSET(lsr, LSR_PE))
   1821 				SET(code, TTY_PE);
   1822 		}
   1823 		if ((*rint)(code, tp) == -1) {
   1824 			/*
   1825 			 * The line discipline's buffer is out of space.
   1826 			 */
   1827 			if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
   1828 				/*
   1829 				 * We're either not using flow control, or the
   1830 				 * line discipline didn't tell us to block for
   1831 				 * some reason.  Either way, we have no way to
   1832 				 * know when there's more space available, so
   1833 				 * just drop the rest of the data.
   1834 				 */
   1835 				get += cc << 1;
   1836 				if (get >= end)
   1837 					get -= com_rbuf_size << 1;
   1838 				cc = 0;
   1839 			} else {
   1840 				/*
   1841 				 * Don't schedule any more receive processing
   1842 				 * until the line discipline tells us there's
   1843 				 * space available (through comhwiflow()).
   1844 				 * Leave the rest of the data in the input
   1845 				 * buffer.
   1846 				 */
   1847 				SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
   1848 			}
   1849 			break;
   1850 		}
   1851 		get += 2;
   1852 		if (get >= end)
   1853 			get = sc->sc_rbuf;
   1854 		cc--;
   1855 	}
   1856 
   1857 	if (cc != scc) {
   1858 		sc->sc_rbget = get;
   1859 		mutex_spin_enter(&sc->sc_lock);
   1860 
   1861 		cc = sc->sc_rbavail += scc - cc;
   1862 		/* Buffers should be ok again, release possible block. */
   1863 		if (cc >= sc->sc_r_lowat) {
   1864 			if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
   1865 				CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
   1866 				SET(sc->sc_ier, IER_ERXRDY);
   1867 #ifdef COM_PXA2X0
   1868 				if (sc->sc_type == COM_TYPE_PXA2x0)
   1869 					SET(sc->sc_ier, IER_ERXTOUT);
   1870 #endif
   1871 				CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, sc->sc_ier);
   1872 			}
   1873 			if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) {
   1874 				CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED);
   1875 				com_hwiflow(sc);
   1876 			}
   1877 		}
   1878 		mutex_spin_exit(&sc->sc_lock);
   1879 	}
   1880 }
   1881 
   1882 integrate void
   1883 com_txsoft(struct com_softc *sc, struct tty *tp)
   1884 {
   1885 
   1886 	CLR(tp->t_state, TS_BUSY);
   1887 	if (ISSET(tp->t_state, TS_FLUSH))
   1888 		CLR(tp->t_state, TS_FLUSH);
   1889 	else
   1890 		ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf));
   1891 	(*tp->t_linesw->l_start)(tp);
   1892 }
   1893 
   1894 integrate void
   1895 com_stsoft(struct com_softc *sc, struct tty *tp)
   1896 {
   1897 	u_char msr, delta;
   1898 
   1899 	mutex_spin_enter(&sc->sc_lock);
   1900 	msr = sc->sc_msr;
   1901 	delta = sc->sc_msr_delta;
   1902 	sc->sc_msr_delta = 0;
   1903 	mutex_spin_exit(&sc->sc_lock);
   1904 
   1905 	if (ISSET(delta, sc->sc_msr_dcd)) {
   1906 		/*
   1907 		 * Inform the tty layer that carrier detect changed.
   1908 		 */
   1909 		(void) (*tp->t_linesw->l_modem)(tp, ISSET(msr, MSR_DCD));
   1910 	}
   1911 
   1912 	if (ISSET(delta, sc->sc_msr_cts)) {
   1913 		/* Block or unblock output according to flow control. */
   1914 		if (ISSET(msr, sc->sc_msr_cts)) {
   1915 			sc->sc_tx_stopped = 0;
   1916 			(*tp->t_linesw->l_start)(tp);
   1917 		} else {
   1918 			sc->sc_tx_stopped = 1;
   1919 		}
   1920 	}
   1921 
   1922 #ifdef COM_DEBUG
   1923 	if (com_debug)
   1924 		comstatus(sc, "com_stsoft");
   1925 #endif
   1926 }
   1927 
   1928 void
   1929 comsoft(void *arg)
   1930 {
   1931 	struct com_softc *sc = arg;
   1932 	struct tty *tp;
   1933 
   1934 	if (COM_ISALIVE(sc) == 0)
   1935 		return;
   1936 
   1937 	tp = sc->sc_tty;
   1938 
   1939 	if (sc->sc_rx_ready) {
   1940 		sc->sc_rx_ready = 0;
   1941 		com_rxsoft(sc, tp);
   1942 	}
   1943 
   1944 	if (sc->sc_st_check) {
   1945 		sc->sc_st_check = 0;
   1946 		com_stsoft(sc, tp);
   1947 	}
   1948 
   1949 	if (sc->sc_tx_done) {
   1950 		sc->sc_tx_done = 0;
   1951 		com_txsoft(sc, tp);
   1952 	}
   1953 }
   1954 
   1955 int
   1956 comintr(void *arg)
   1957 {
   1958 	struct com_softc *sc = arg;
   1959 	struct com_regs *regsp = &sc->sc_regs;
   1960 
   1961 	u_char *put, *end;
   1962 	u_int cc;
   1963 	u_char lsr, iir;
   1964 
   1965 	if (COM_ISALIVE(sc) == 0)
   1966 		return (0);
   1967 
   1968 	KASSERT(regsp != NULL);
   1969 
   1970 	mutex_spin_enter(&sc->sc_lock);
   1971 	iir = CSR_READ_1(regsp, COM_REG_IIR);
   1972 
   1973 	/* Handle ns16750-specific busy interrupt. */
   1974 #ifdef COM_16750
   1975 	int timeout;
   1976 	if ((iir & IIR_BUSY) == IIR_BUSY) {
   1977 		for (timeout = 10000;
   1978 		    (CSR_READ_1(regsp, COM_REG_USR) & 0x1) != 0; timeout--)
   1979 			if (timeout <= 0) {
   1980 				aprint_error_dev(sc->sc_dev,
   1981 				    "timeout while waiting for BUSY interrupt "
   1982 				    "acknowledge\n");
   1983 				mutex_spin_exit(&sc->sc_lock);
   1984 				return (0);
   1985 			}
   1986 
   1987 		CSR_WRITE_1(regsp, COM_REG_LCR, sc->sc_lcr);
   1988 		iir = CSR_READ_1(regsp, COM_REG_IIR);
   1989 	}
   1990 #endif /* COM_16750 */
   1991 
   1992 
   1993 	if (ISSET(iir, IIR_NOPEND)) {
   1994 		mutex_spin_exit(&sc->sc_lock);
   1995 		return (0);
   1996 	}
   1997 
   1998 	end = sc->sc_ebuf;
   1999 	put = sc->sc_rbput;
   2000 	cc = sc->sc_rbavail;
   2001 
   2002 again:	do {
   2003 		u_char	msr, delta;
   2004 
   2005 		lsr = CSR_READ_1(regsp, COM_REG_LSR);
   2006 		if (ISSET(lsr, LSR_BI)) {
   2007 			int cn_trapped = 0; /* see above: cn_trap() */
   2008 
   2009 			cn_check_magic(sc->sc_tty->t_dev,
   2010 				       CNC_BREAK, com_cnm_state);
   2011 			if (cn_trapped)
   2012 				continue;
   2013 #if defined(KGDB) && !defined(DDB)
   2014 			if (ISSET(sc->sc_hwflags, COM_HW_KGDB)) {
   2015 				kgdb_connect(1);
   2016 				continue;
   2017 			}
   2018 #endif
   2019 		}
   2020 
   2021 		if (ISSET(lsr, LSR_RCV_MASK) &&
   2022 		    !ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
   2023 			while (cc > 0) {
   2024 				int cn_trapped = 0;
   2025 				put[0] = CSR_READ_1(regsp, COM_REG_RXDATA);
   2026 				put[1] = lsr;
   2027 				cn_check_magic(sc->sc_tty->t_dev,
   2028 					       put[0], com_cnm_state);
   2029 				if (cn_trapped)
   2030 					goto next;
   2031 				put += 2;
   2032 				if (put >= end)
   2033 					put = sc->sc_rbuf;
   2034 				cc--;
   2035 			next:
   2036 				lsr = CSR_READ_1(regsp, COM_REG_LSR);
   2037 				if (!ISSET(lsr, LSR_RCV_MASK))
   2038 					break;
   2039 			}
   2040 
   2041 			/*
   2042 			 * Current string of incoming characters ended because
   2043 			 * no more data was available or we ran out of space.
   2044 			 * Schedule a receive event if any data was received.
   2045 			 * If we're out of space, turn off receive interrupts.
   2046 			 */
   2047 			sc->sc_rbput = put;
   2048 			sc->sc_rbavail = cc;
   2049 			if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
   2050 				sc->sc_rx_ready = 1;
   2051 
   2052 			/*
   2053 			 * See if we are in danger of overflowing a buffer. If
   2054 			 * so, use hardware flow control to ease the pressure.
   2055 			 */
   2056 			if (!ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED) &&
   2057 			    cc < sc->sc_r_hiwat) {
   2058 				SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
   2059 				com_hwiflow(sc);
   2060 			}
   2061 
   2062 			/*
   2063 			 * If we're out of space, disable receive interrupts
   2064 			 * until the queue has drained a bit.
   2065 			 */
   2066 			if (!cc) {
   2067 				SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
   2068 #ifdef COM_PXA2X0
   2069 				if (sc->sc_type == COM_TYPE_PXA2x0)
   2070 					CLR(sc->sc_ier, IER_ERXRDY|IER_ERXTOUT);
   2071 				else
   2072 #endif
   2073 					CLR(sc->sc_ier, IER_ERXRDY);
   2074 				CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
   2075 			}
   2076 		} else {
   2077 			if ((iir & (IIR_RXRDY|IIR_TXRDY)) == IIR_RXRDY) {
   2078 				(void) CSR_READ_1(regsp, COM_REG_RXDATA);
   2079 				continue;
   2080 			}
   2081 		}
   2082 
   2083 		msr = CSR_READ_1(regsp, COM_REG_MSR);
   2084 		delta = msr ^ sc->sc_msr;
   2085 		sc->sc_msr = msr;
   2086 		if ((sc->sc_pps_state.ppsparam.mode & PPS_CAPTUREBOTH) &&
   2087 		    (delta & MSR_DCD)) {
   2088 			mutex_spin_enter(&timecounter_lock);
   2089 			pps_capture(&sc->sc_pps_state);
   2090 			pps_event(&sc->sc_pps_state,
   2091 			    (msr & MSR_DCD) ?
   2092 			    PPS_CAPTUREASSERT :
   2093 			    PPS_CAPTURECLEAR);
   2094 			mutex_spin_exit(&timecounter_lock);
   2095 		}
   2096 
   2097 		/*
   2098 		 * Process normal status changes
   2099 		 */
   2100 		if (ISSET(delta, sc->sc_msr_mask)) {
   2101 			SET(sc->sc_msr_delta, delta);
   2102 
   2103 			/*
   2104 			 * Stop output immediately if we lose the output
   2105 			 * flow control signal or carrier detect.
   2106 			 */
   2107 			if (ISSET(~msr, sc->sc_msr_mask)) {
   2108 				sc->sc_tbc = 0;
   2109 				sc->sc_heldtbc = 0;
   2110 #ifdef COM_DEBUG
   2111 				if (com_debug)
   2112 					comstatus(sc, "comintr  ");
   2113 #endif
   2114 			}
   2115 
   2116 			sc->sc_st_check = 1;
   2117 		}
   2118 	} while (!ISSET((iir =
   2119 	    CSR_READ_1(regsp, COM_REG_IIR)), IIR_NOPEND) &&
   2120 	    /*
   2121 	     * Since some device (e.g., ST16C1550) doesn't clear IIR_TXRDY
   2122 	     * by IIR read, so we can't do this way: `process all interrupts,
   2123 	     * then do TX if possible'.
   2124 	     */
   2125 	    (iir & IIR_IMASK) != IIR_TXRDY);
   2126 
   2127 	/*
   2128 	 * Read LSR again, since there may be an interrupt between
   2129 	 * the last LSR read and IIR read above.
   2130 	 */
   2131 	lsr = CSR_READ_1(regsp, COM_REG_LSR);
   2132 
   2133 	/*
   2134 	 * See if data can be transmitted as well.
   2135 	 * Schedule tx done event if no data left
   2136 	 * and tty was marked busy.
   2137 	 */
   2138 	if (ISSET(lsr, LSR_TXRDY)) {
   2139 		/*
   2140 		 * If we've delayed a parameter change, do it now, and restart
   2141 		 * output.
   2142 		 */
   2143 		if (sc->sc_heldchange) {
   2144 			com_loadchannelregs(sc);
   2145 			sc->sc_heldchange = 0;
   2146 			sc->sc_tbc = sc->sc_heldtbc;
   2147 			sc->sc_heldtbc = 0;
   2148 		}
   2149 
   2150 		/* Output the next chunk of the contiguous buffer, if any. */
   2151 		if (sc->sc_tbc > 0) {
   2152 			u_int n;
   2153 
   2154 			n = sc->sc_tbc;
   2155 			if (n > sc->sc_fifolen)
   2156 				n = sc->sc_fifolen;
   2157 			CSR_WRITE_MULTI(regsp, COM_REG_TXDATA, sc->sc_tba, n);
   2158 			sc->sc_tbc -= n;
   2159 			sc->sc_tba += n;
   2160 		} else {
   2161 			/* Disable transmit completion interrupts if necessary. */
   2162 			if (ISSET(sc->sc_ier, IER_ETXRDY)) {
   2163 				CLR(sc->sc_ier, IER_ETXRDY);
   2164 				CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
   2165 			}
   2166 			if (sc->sc_tx_busy) {
   2167 				sc->sc_tx_busy = 0;
   2168 				sc->sc_tx_done = 1;
   2169 			}
   2170 		}
   2171 	}
   2172 
   2173 	if (!ISSET((iir = CSR_READ_1(regsp, COM_REG_IIR)), IIR_NOPEND))
   2174 		goto again;
   2175 
   2176 	mutex_spin_exit(&sc->sc_lock);
   2177 
   2178 	/* Wake up the poller. */
   2179 	softint_schedule(sc->sc_si);
   2180 
   2181 #ifdef RND_COM
   2182 	rnd_add_uint32(&sc->rnd_source, iir | lsr);
   2183 #endif
   2184 
   2185 	return (1);
   2186 }
   2187 
   2188 /*
   2189  * The following functions are polled getc and putc routines, shared
   2190  * by the console and kgdb glue.
   2191  *
   2192  * The read-ahead code is so that you can detect pending in-band
   2193  * cn_magic in polled mode while doing output rather than having to
   2194  * wait until the kernel decides it needs input.
   2195  */
   2196 
   2197 #define MAX_READAHEAD	20
   2198 static int com_readahead[MAX_READAHEAD];
   2199 static int com_readaheadcount = 0;
   2200 
   2201 int
   2202 com_common_getc(dev_t dev, struct com_regs *regsp)
   2203 {
   2204 	int s = splserial();
   2205 	u_char stat, c;
   2206 
   2207 	/* got a character from reading things earlier */
   2208 	if (com_readaheadcount > 0) {
   2209 		int i;
   2210 
   2211 		c = com_readahead[0];
   2212 		for (i = 1; i < com_readaheadcount; i++) {
   2213 			com_readahead[i-1] = com_readahead[i];
   2214 		}
   2215 		com_readaheadcount--;
   2216 		splx(s);
   2217 		return (c);
   2218 	}
   2219 
   2220 	/* don't block until a character becomes available */
   2221 	if (!ISSET(stat = CSR_READ_1(regsp, COM_REG_LSR), LSR_RXRDY)) {
   2222 		splx(s);
   2223 		return -1;
   2224 	}
   2225 
   2226 	c = CSR_READ_1(regsp, COM_REG_RXDATA);
   2227 	stat = CSR_READ_1(regsp, COM_REG_IIR);
   2228 	{
   2229 		int cn_trapped = 0;	/* required by cn_trap, see above */
   2230 #ifdef DDB
   2231 		extern int db_active;
   2232 		if (!db_active)
   2233 #endif
   2234 			cn_check_magic(dev, c, com_cnm_state);
   2235 	}
   2236 	splx(s);
   2237 	return (c);
   2238 }
   2239 
   2240 static void
   2241 com_common_putc(dev_t dev, struct com_regs *regsp, int c)
   2242 {
   2243 	int s = splserial();
   2244 	int cin, stat, timo;
   2245 
   2246 	if (com_readaheadcount < MAX_READAHEAD
   2247 	     && ISSET(stat = CSR_READ_1(regsp, COM_REG_LSR), LSR_RXRDY)) {
   2248 		int cn_trapped = 0;
   2249 		cin = CSR_READ_1(regsp, COM_REG_RXDATA);
   2250 		stat = CSR_READ_1(regsp, COM_REG_IIR);
   2251 		cn_check_magic(dev, cin, com_cnm_state);
   2252 		com_readahead[com_readaheadcount++] = cin;
   2253 	}
   2254 
   2255 	/* wait for any pending transmission to finish */
   2256 	timo = 150000;
   2257 	while (!ISSET(CSR_READ_1(regsp, COM_REG_LSR), LSR_TXRDY) && --timo)
   2258 		continue;
   2259 
   2260 	CSR_WRITE_1(regsp, COM_REG_TXDATA, c);
   2261 	COM_BARRIER(regsp, BR | BW);
   2262 
   2263 	splx(s);
   2264 }
   2265 
   2266 /*
   2267  * Initialize UART for use as console or KGDB line.
   2268  */
   2269 int
   2270 cominit(struct com_regs *regsp, int rate, int frequency, int type,
   2271     tcflag_t cflag)
   2272 {
   2273 
   2274 	if (bus_space_map(regsp->cr_iot, regsp->cr_iobase, regsp->cr_nports, 0,
   2275 		&regsp->cr_ioh))
   2276 		return (ENOMEM); /* ??? */
   2277 
   2278 	if (type == COM_TYPE_OMAP) {
   2279 		/* disable before changing settings */
   2280 		CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_DISABLE);
   2281 	}
   2282 
   2283 	rate = comspeed(rate, frequency, type);
   2284 	if (__predict_true(rate != -1)) {
   2285 		if (type == COM_TYPE_AU1x00) {
   2286 			CSR_WRITE_2(regsp, COM_REG_DLBL, rate);
   2287 		} else {
   2288 			/* no EFR on alchemy */
   2289 			if (type != COM_TYPE_16550_NOERS) {
   2290 				CSR_WRITE_1(regsp, COM_REG_LCR, LCR_EERS);
   2291 				CSR_WRITE_1(regsp, COM_REG_EFR, 0);
   2292 			}
   2293 			CSR_WRITE_1(regsp, COM_REG_LCR, LCR_DLAB);
   2294 			CSR_WRITE_1(regsp, COM_REG_DLBL, rate & 0xff);
   2295 			CSR_WRITE_1(regsp, COM_REG_DLBH, rate >> 8);
   2296 		}
   2297 	}
   2298 	CSR_WRITE_1(regsp, COM_REG_LCR, cflag2lcr(cflag));
   2299 	CSR_WRITE_1(regsp, COM_REG_MCR, MCR_DTR | MCR_RTS);
   2300 	CSR_WRITE_1(regsp, COM_REG_FIFO,
   2301 	    FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1);
   2302 
   2303 	if (type == COM_TYPE_OMAP) {
   2304 		/* setup the fifos.  the FCR value is not used as long
   2305 		   as SCR[6] and SCR[7] are 0, which they are at reset
   2306 		   and we never touch the SCR register */
   2307 		uint8_t rx_fifo_trig = 40;
   2308 		uint8_t tx_fifo_trig = 60;
   2309 		uint8_t rx_start = 8;
   2310 		uint8_t rx_halt = 60;
   2311 		uint8_t tlr_value = ((rx_fifo_trig>>2) << 4) | (tx_fifo_trig>>2);
   2312 		uint8_t tcr_value = ((rx_start>>2) << 4) | (rx_halt>>2);
   2313 
   2314 		/* enable access to TCR & TLR */
   2315 		CSR_WRITE_1(regsp, COM_REG_MCR, MCR_DTR | MCR_RTS | MCR_TCR_TLR);
   2316 
   2317 		/* write tcr and tlr values */
   2318 		CSR_WRITE_1(regsp, COM_REG_TLR, tlr_value);
   2319 		CSR_WRITE_1(regsp, COM_REG_TCR, tcr_value);
   2320 
   2321 		/* disable access to TCR & TLR */
   2322 		CSR_WRITE_1(regsp, COM_REG_MCR, MCR_DTR | MCR_RTS);
   2323 
   2324 		/* enable again, but mode is based on speed */
   2325 		if (rate > 230400) {
   2326 			CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_UART_13X);
   2327 		} else {
   2328 			CSR_WRITE_1(regsp, COM_REG_MDR1, MDR1_MODE_UART_16X);
   2329 		}
   2330 	}
   2331 
   2332 #ifdef COM_PXA2X0
   2333 	if (type == COM_TYPE_PXA2x0)
   2334 		CSR_WRITE_1(regsp, COM_REG_IER, IER_EUART);
   2335 	else
   2336 #endif
   2337 		CSR_WRITE_1(regsp, COM_REG_IER, 0);
   2338 
   2339 	return (0);
   2340 }
   2341 
   2342 int
   2343 comcnattach1(struct com_regs *regsp, int rate, int frequency, int type,
   2344     tcflag_t cflag)
   2345 {
   2346 	int res;
   2347 
   2348 	comcons_info.regs = *regsp;
   2349 
   2350 	res = cominit(&comcons_info.regs, rate, frequency, type, cflag);
   2351 	if (res)
   2352 		return (res);
   2353 
   2354 	cn_tab = &comcons;
   2355 	cn_init_magic(&com_cnm_state);
   2356 	cn_set_magic("\047\001"); /* default magic is BREAK */
   2357 
   2358 	comcons_info.frequency = frequency;
   2359 	comcons_info.type = type;
   2360 	comcons_info.rate = rate;
   2361 	comcons_info.cflag = cflag;
   2362 
   2363 	return (0);
   2364 }
   2365 
   2366 int
   2367 comcnattach(bus_space_tag_t iot, bus_addr_t iobase, int rate, int frequency,
   2368     int type, tcflag_t cflag)
   2369 {
   2370 	struct com_regs	regs;
   2371 
   2372 	memset(&regs, 0, sizeof regs);
   2373 	regs.cr_iot = iot;
   2374 	regs.cr_iobase = iobase;
   2375 	regs.cr_nports = COM_NPORTS;
   2376 #ifdef	COM_REGMAP
   2377 	memcpy(regs.cr_map, com_std_map, sizeof (regs.cr_map));
   2378 #endif
   2379 
   2380 	return comcnattach1(&regs, rate, frequency, type, cflag);
   2381 }
   2382 
   2383 static int
   2384 comcnreattach(void)
   2385 {
   2386 	return comcnattach1(&comcons_info.regs, comcons_info.rate,
   2387 	    comcons_info.frequency, comcons_info.type, comcons_info.cflag);
   2388 }
   2389 
   2390 int
   2391 comcngetc(dev_t dev)
   2392 {
   2393 
   2394 	return (com_common_getc(dev, &comcons_info.regs));
   2395 }
   2396 
   2397 /*
   2398  * Console kernel output character routine.
   2399  */
   2400 void
   2401 comcnputc(dev_t dev, int c)
   2402 {
   2403 
   2404 	com_common_putc(dev, &comcons_info.regs, c);
   2405 }
   2406 
   2407 void
   2408 comcnpollc(dev_t dev, int on)
   2409 {
   2410 
   2411 	com_readaheadcount = 0;
   2412 }
   2413 
   2414 #ifdef KGDB
   2415 int
   2416 com_kgdb_attach1(struct com_regs *regsp, int rate, int frequency, int type,
   2417     tcflag_t cflag)
   2418 {
   2419 	int res;
   2420 
   2421 	if (bus_space_is_equal(regsp->cr_iot, comcons_info.regs.cr_iot) &&
   2422 	    regsp->cr_iobase == comcons_info.regs.cr_iobase) {
   2423 #if !defined(DDB)
   2424 		return (EBUSY); /* cannot share with console */
   2425 #else
   2426 		comkgdbregs = *regsp;
   2427 		comkgdbregs.cr_ioh = comcons_info.regs.cr_ioh;
   2428 #endif
   2429 	} else {
   2430 		comkgdbregs = *regsp;
   2431 		res = cominit(&comkgdbregs, rate, frequency, type, cflag);
   2432 		if (res)
   2433 			return (res);
   2434 
   2435 		/*
   2436 		 * XXXfvdl this shouldn't be needed, but the cn_magic goo
   2437 		 * expects this to be initialized
   2438 		 */
   2439 		cn_init_magic(&com_cnm_state);
   2440 		cn_set_magic("\047\001");
   2441 	}
   2442 
   2443 	kgdb_attach(com_kgdb_getc, com_kgdb_putc, NULL);
   2444 	kgdb_dev = 123; /* unneeded, only to satisfy some tests */
   2445 
   2446 	return (0);
   2447 }
   2448 
   2449 int
   2450 com_kgdb_attach(bus_space_tag_t iot, bus_addr_t iobase, int rate,
   2451     int frequency, int type, tcflag_t cflag)
   2452 {
   2453 	struct com_regs regs;
   2454 
   2455 	regs.cr_iot = iot;
   2456 	regs.cr_nports = COM_NPORTS;
   2457 	regs.cr_iobase = iobase;
   2458 #ifdef COM_REGMAP
   2459 	memcpy(regs.cr_map, com_std_map, sizeof (regs.cr_map));
   2460 #endif
   2461 
   2462 	return com_kgdb_attach1(&regs, rate, frequency, type, cflag);
   2463 }
   2464 
   2465 /* ARGSUSED */
   2466 int
   2467 com_kgdb_getc(void *arg)
   2468 {
   2469 
   2470 	return (com_common_getc(NODEV, &comkgdbregs));
   2471 }
   2472 
   2473 /* ARGSUSED */
   2474 void
   2475 com_kgdb_putc(void *arg, int c)
   2476 {
   2477 
   2478 	com_common_putc(NODEV, &comkgdbregs, c);
   2479 }
   2480 #endif /* KGDB */
   2481 
   2482 /* helper function to identify the com ports used by
   2483  console or KGDB (and not yet autoconf attached) */
   2484 int
   2485 com_is_console(bus_space_tag_t iot, bus_addr_t iobase, bus_space_handle_t *ioh)
   2486 {
   2487 	bus_space_handle_t help;
   2488 
   2489 	if (!comconsattached &&
   2490 	    bus_space_is_equal(iot, comcons_info.regs.cr_iot) &&
   2491 	    iobase == comcons_info.regs.cr_iobase)
   2492 		help = comcons_info.regs.cr_ioh;
   2493 #ifdef KGDB
   2494 	else if (!com_kgdb_attached &&
   2495 	    bus_space_is_equal(iot, comkgdbregs.cr_iot) &&
   2496 	    iobase == comkgdbregs.cr_iobase)
   2497 		help = comkgdbregs.cr_ioh;
   2498 #endif
   2499 	else
   2500 		return (0);
   2501 
   2502 	if (ioh)
   2503 		*ioh = help;
   2504 	return (1);
   2505 }
   2506 
   2507 /*
   2508  * this routine exists to serve as a shutdown hook for systems that
   2509  * have firmware which doesn't interact properly with a com device in
   2510  * FIFO mode.
   2511  */
   2512 bool
   2513 com_cleanup(device_t self, int how)
   2514 {
   2515 	struct com_softc *sc = device_private(self);
   2516 
   2517 	if (ISSET(sc->sc_hwflags, COM_HW_FIFO))
   2518 		CSR_WRITE_1(&sc->sc_regs, COM_REG_FIFO, 0);
   2519 
   2520 	return true;
   2521 }
   2522 
   2523 bool
   2524 com_suspend(device_t self, const pmf_qual_t *qual)
   2525 {
   2526 	struct com_softc *sc = device_private(self);
   2527 
   2528 #if 0
   2529 	if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE) && cn_tab == &comcons)
   2530 		cn_tab = &comcons_suspend;
   2531 #endif
   2532 
   2533 	CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, 0);
   2534 	(void)CSR_READ_1(&sc->sc_regs, COM_REG_IIR);
   2535 
   2536 	return true;
   2537 }
   2538 
   2539 bool
   2540 com_resume(device_t self, const pmf_qual_t *qual)
   2541 {
   2542 	struct com_softc *sc = device_private(self);
   2543 
   2544 	mutex_spin_enter(&sc->sc_lock);
   2545 	com_loadchannelregs(sc);
   2546 	mutex_spin_exit(&sc->sc_lock);
   2547 
   2548 	return true;
   2549 }
   2550