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zs.c revision 1.20
      1 /*	$NetBSD: zs.c,v 1.20 2000/05/19 05:26:17 eeh Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1996 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Gordon W. Ross.
      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  * 3. All advertising materials mentioning features or use of this software
     19  *    must display the following acknowledgement:
     20  *        This product includes software developed by the NetBSD
     21  *        Foundation, Inc. and its contributors.
     22  * 4. Neither the name of The NetBSD Foundation nor the names of its
     23  *    contributors may be used to endorse or promote products derived
     24  *    from this software without specific prior written permission.
     25  *
     26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     36  * POSSIBILITY OF SUCH DAMAGE.
     37  */
     38 
     39 /*
     40  * Zilog Z8530 Dual UART driver (machine-dependent part)
     41  *
     42  * Runs two serial lines per chip using slave drivers.
     43  * Plain tty/async lines use the zs_async slave.
     44  * Sun keyboard/mouse uses the zs_kbd/zs_ms slaves.
     45  */
     46 
     47 #include "opt_ddb.h"
     48 
     49 #include <sys/param.h>
     50 #include <sys/systm.h>
     51 #include <sys/conf.h>
     52 #include <sys/device.h>
     53 #include <sys/file.h>
     54 #include <sys/ioctl.h>
     55 #include <sys/kernel.h>
     56 #include <sys/proc.h>
     57 #include <sys/tty.h>
     58 #include <sys/time.h>
     59 #include <sys/syslog.h>
     60 
     61 #include <machine/autoconf.h>
     62 #include <machine/openfirm.h>
     63 #include <machine/bsd_openprom.h>
     64 #include <machine/conf.h>
     65 #include <machine/cpu.h>
     66 #include <machine/eeprom.h>
     67 #include <machine/psl.h>
     68 #include <machine/z8530var.h>
     69 
     70 #include <dev/cons.h>
     71 #include <dev/ic/z8530reg.h>
     72 #include <ddb/db_output.h>
     73 
     74 #include <sparc64/sparc64/vaddrs.h>
     75 #include <sparc64/dev/cons.h>
     76 
     77 #include "kbd.h"	/* NKBD */
     78 #include "zs.h" 	/* NZS */
     79 
     80 /* Make life easier for the initialized arrays here. */
     81 #if NZS < 3
     82 #undef  NZS
     83 #define NZS 3
     84 #endif
     85 
     86 /*
     87  * Some warts needed by z8530tty.c -
     88  * The default parity REALLY needs to be the same as the PROM uses,
     89  * or you can not see messages done with printf during boot-up...
     90  */
     91 int zs_def_cflag = (CREAD | CS8 | HUPCL);
     92 int zs_major = 12;
     93 
     94 /*
     95  * The Sun provides a 4.9152 MHz clock to the ZS chips.
     96  */
     97 #define PCLK	(9600 * 512)	/* PCLK pin input clock rate */
     98 
     99 #define	ZS_DELAY()
    100 
    101 /* The layout of this is hardware-dependent (padding, order). */
    102 struct zschan {
    103 	volatile u_char	zc_csr;		/* ctrl,status, and indirect access */
    104 	u_char		zc_xxx0;
    105 	volatile u_char	zc_data;	/* data */
    106 	u_char		zc_xxx1;
    107 };
    108 struct zsdevice {
    109 	/* Yes, they are backwards. */
    110 	struct	zschan zs_chan_b;
    111 	struct	zschan zs_chan_a;
    112 };
    113 
    114 /* ZS channel used as the console device (if any) */
    115 void *zs_conschan_get, *zs_conschan_put;
    116 
    117 /* Saved PROM mappings */
    118 static struct zsdevice *zsaddr[NZS];
    119 
    120 static u_char zs_init_reg[16] = {
    121 	0,	/* 0: CMD (reset, etc.) */
    122 	0,	/* 1: No interrupts yet. */
    123 	0,	/* 2: IVECT */
    124 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
    125 	ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
    126 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
    127 	0,	/* 6: TXSYNC/SYNCLO */
    128 	0,	/* 7: RXSYNC/SYNCHI */
    129 	0,	/* 8: alias for data port */
    130 	ZSWR9_MASTER_IE | ZSWR9_NO_VECTOR,
    131 	0,	/*10: Misc. TX/RX control bits */
    132 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
    133 	((PCLK/32)/9600)-2,	/*12: BAUDLO (default=9600) */
    134 	0,			/*13: BAUDHI (default=9600) */
    135 	ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
    136 	ZSWR15_BREAK_IE,
    137 };
    138 
    139 /* Console ops */
    140 static int  zscngetc __P((dev_t));
    141 static void zscnputc __P((dev_t, int));
    142 static void zscnpollc __P((dev_t, int));
    143 
    144 struct consdev zs_consdev = {
    145 	NULL,
    146 	NULL,
    147 	zscngetc,
    148 	zscnputc,
    149 	zscnpollc,
    150 	NULL,
    151 };
    152 
    153 
    154 /****************************************************************
    155  * Autoconfig
    156  ****************************************************************/
    157 
    158 /* Definition of the driver for autoconfig. */
    159 static int  zs_match_mainbus __P((struct device *, struct cfdata *, void *));
    160 static void zs_attach_mainbus __P((struct device *, struct device *, void *));
    161 
    162 static void zs_attach __P((struct zsc_softc *, struct zsdevice *, int));
    163 static int  zs_print __P((void *, const char *name));
    164 
    165 /* Do we really need this ? */
    166 struct cfattach zs_ca = {
    167 	sizeof(struct zsc_softc), zs_match_mainbus, zs_attach_mainbus
    168 };
    169 
    170 struct cfattach zs_mainbus_ca = {
    171 	sizeof(struct zsc_softc), zs_match_mainbus, zs_attach_mainbus
    172 };
    173 
    174 extern struct cfdriver zs_cd;
    175 extern int stdinnode;
    176 extern int fbnode;
    177 
    178 /* Interrupt handlers. */
    179 static int zshard __P((void *));
    180 static int zssoft __P((void *));
    181 static struct intrhand levelsoft = { zssoft, 0, IPL_SOFTSERIAL };
    182 
    183 static int zs_get_speed __P((struct zs_chanstate *));
    184 
    185 /* Console device support */
    186 static int zs_console_flags __P((int, int, int));
    187 
    188 /* Power management hooks */
    189 int  zs_enable __P((struct zs_chanstate *));
    190 void zs_disable __P((struct zs_chanstate *));
    191 
    192 /*
    193  * Is the zs chip present?
    194  */
    195 static int
    196 zs_match_mainbus(parent, cf, aux)
    197 	struct device *parent;
    198 	struct cfdata *cf;
    199 	void *aux;
    200 {
    201 	struct sbus_attach_args *sa = aux;
    202 
    203 	if (strcmp(cf->cf_driver->cd_name, sa->sa_name) != 0)
    204 		return (0);
    205 
    206 	return (1);
    207 }
    208 
    209 static void
    210 zs_attach_mainbus(parent, self, aux)
    211 	struct device *parent;
    212 	struct device *self;
    213 	void *aux;
    214 {
    215 	struct zsc_softc *zsc = (void *) self;
    216 	struct sbus_attach_args *sa = aux;
    217 	int zs_unit = zsc->zsc_dev.dv_unit;
    218 
    219 	if (sa->sa_nintr == 0) {
    220 		printf(" no interrupt lines\n");
    221 		return;
    222 	}
    223 
    224 	/* Use the mapping setup by the Sun PROM. */
    225 	if (zsaddr[zs_unit] == NULL) {
    226 		/* Only map registers once. */
    227 		if (sa->sa_npromvaddrs) {
    228 			/*
    229 			 * We're converting from a 32-bit pointer to a 64-bit
    230 			 * pointer.  Since the 32-bit entity is negative, but
    231 			 * the kernel is still mapped into the lower 4GB
    232 			 * range, this needs to be zero-extended.
    233 			 *
    234 			 * XXXXX If we map the kernel and devices into the
    235 			 * high 4GB range, this needs to be changed to
    236 			 * sign-extend the address.
    237 			 */
    238 			zsaddr[zs_unit] =
    239 				(struct zsdevice *)
    240 				(uintptr_t)sa->sa_promvaddrs[0];
    241 		} else {
    242 			bus_space_handle_t kvaddr;
    243 
    244 			if (sbus_bus_map(sa->sa_bustag, sa->sa_slot,
    245 					 sa->sa_offset,
    246 					 sa->sa_size,
    247 					 BUS_SPACE_MAP_LINEAR,
    248 					 0, &kvaddr) != 0) {
    249 				printf("%s @ sbus: cannot map registers\n",
    250 				       self->dv_xname);
    251 				return;
    252 			}
    253 			zsaddr[zs_unit] = (struct zsdevice *)
    254 				(uintptr_t)kvaddr;
    255 		}
    256 	}
    257 	zsc->zsc_bustag = sa->sa_bustag;
    258 	zsc->zsc_dmatag = sa->sa_dmatag;
    259 	zsc->zsc_promunit = getpropint(sa->sa_node, "slave", -2);
    260 	zsc->zsc_node = sa->sa_node;
    261 	zs_attach(zsc, zsaddr[zs_unit], sa->sa_pri);
    262 }
    263 
    264 /*
    265  * Attach a found zs.
    266  *
    267  * USE ROM PROPERTIES port-a-ignore-cd AND port-b-ignore-cd FOR
    268  * SOFT CARRIER, AND keyboard PROPERTY FOR KEYBOARD/MOUSE?
    269  */
    270 static void
    271 zs_attach(zsc, zsd, pri)
    272 	struct zsc_softc *zsc;
    273 	struct zsdevice *zsd;
    274 	int pri;
    275 {
    276 	struct zsc_attach_args zsc_args;
    277 	struct zs_chanstate *cs;
    278 	int s, channel;
    279 	static int didintr, prevpri;
    280 
    281 	if (zsd == NULL) {
    282 		printf("configuration incomplete\n");
    283 		return;
    284 	}
    285 
    286 	printf(" softpri %d\n", PIL_TTY);
    287 
    288 	/*
    289 	 * Initialize software state for each channel.
    290 	 */
    291 	for (channel = 0; channel < 2; channel++) {
    292 		struct zschan *zc;
    293 
    294 		zsc_args.channel = channel;
    295 		cs = &zsc->zsc_cs_store[channel];
    296 		zsc->zsc_cs[channel] = cs;
    297 
    298 		cs->cs_channel = channel;
    299 		cs->cs_private = NULL;
    300 		cs->cs_ops = &zsops_null;
    301 		cs->cs_brg_clk = PCLK / 16;
    302 
    303 		zc = (channel == 0) ? &zsd->zs_chan_a : &zsd->zs_chan_b;
    304 
    305 		zsc_args.hwflags = zs_console_flags(zsc->zsc_promunit,
    306 						    zsc->zsc_node,
    307 						    channel);
    308 
    309 		if (zsc_args.hwflags & ZS_HWFLAG_CONSOLE) {
    310 			zsc_args.hwflags |= ZS_HWFLAG_USE_CONSDEV;
    311 			zsc_args.consdev = &zs_consdev;
    312 		}
    313 
    314 		if ((zsc_args.hwflags & ZS_HWFLAG_CONSOLE_INPUT) != 0) {
    315 			zs_conschan_get = zc;
    316 		}
    317 		if ((zsc_args.hwflags & ZS_HWFLAG_CONSOLE_OUTPUT) != 0) {
    318 			zs_conschan_put = zc;
    319 		}
    320 		/* Childs need to set cn_dev, etc */
    321 
    322 		cs->cs_reg_csr  = &zc->zc_csr;
    323 		cs->cs_reg_data = &zc->zc_data;
    324 
    325 		bcopy(zs_init_reg, cs->cs_creg, 16);
    326 		bcopy(zs_init_reg, cs->cs_preg, 16);
    327 
    328 		/* XXX: Consult PROM properties for this?! */
    329 		cs->cs_defspeed = zs_get_speed(cs);
    330 		cs->cs_defcflag = zs_def_cflag;
    331 
    332 		/* Make these correspond to cs_defcflag (-crtscts) */
    333 		cs->cs_rr0_dcd = ZSRR0_DCD;
    334 		cs->cs_rr0_cts = 0;
    335 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
    336 		cs->cs_wr5_rts = 0;
    337 
    338 		/*
    339 		 * Clear the master interrupt enable.
    340 		 * The INTENA is common to both channels,
    341 		 * so just do it on the A channel.
    342 		 */
    343 		if (channel == 0) {
    344 			zs_write_reg(cs, 9, 0);
    345 		}
    346 
    347 		/*
    348 		 * Look for a child driver for this channel.
    349 		 * The child attach will setup the hardware.
    350 		 */
    351 		if (!config_found(&zsc->zsc_dev, (void *)&zsc_args, zs_print)) {
    352 			/* No sub-driver.  Just reset it. */
    353 			u_char reset = (channel == 0) ?
    354 				ZSWR9_A_RESET : ZSWR9_B_RESET;
    355 			s = splzs();
    356 			zs_write_reg(cs,  9, reset);
    357 			splx(s);
    358 		}
    359 	}
    360 
    361 	/*
    362 	 * Now safe to install interrupt handlers.  Note the arguments
    363 	 * to the interrupt handlers aren't used.  Note, we only do this
    364 	 * once since both SCCs interrupt at the same level and vector.
    365 	 */
    366 	if (!didintr) {
    367 		didintr = 1;
    368 		prevpri = pri;
    369 		bus_intr_establish(zsc->zsc_bustag, pri, 0, zshard, NULL);
    370 		intr_establish(PIL_TTY, &levelsoft);
    371 	} else if (pri != prevpri)
    372 		panic("broken zs interrupt scheme");
    373 
    374 	evcnt_attach(&zsc->zsc_dev, "intr", &zsc->zsc_intrcnt);
    375 
    376 	/*
    377 	 * Set the master interrupt enable and interrupt vector.
    378 	 * (common to both channels, do it on A)
    379 	 */
    380 	cs = zsc->zsc_cs[0];
    381 	s = splhigh();
    382 	/* interrupt vector */
    383 	zs_write_reg(cs, 2, zs_init_reg[2]);
    384 	/* master interrupt control (enable) */
    385 	zs_write_reg(cs, 9, zs_init_reg[9]);
    386 	splx(s);
    387 
    388 #if 0
    389 	/*
    390 	 * XXX: L1A hack - We would like to be able to break into
    391 	 * the debugger during the rest of autoconfiguration, so
    392 	 * lower interrupts just enough to let zs interrupts in.
    393 	 * This is done after both zs devices are attached.
    394 	 */
    395 	if (zsc->zsc_promunit == 1) {
    396 		printf("zs1: enabling zs interrupts\n");
    397 		(void)splfd(); /* XXX: splzs - 1 */
    398 	}
    399 #endif
    400 }
    401 
    402 static int
    403 zs_print(aux, name)
    404 	void *aux;
    405 	const char *name;
    406 {
    407 	struct zsc_attach_args *args = aux;
    408 
    409 	if (name != NULL)
    410 		printf("%s: ", name);
    411 
    412 	if (args->channel != -1)
    413 		printf(" channel %d", args->channel);
    414 
    415 	return (UNCONF);
    416 }
    417 
    418 static volatile int zssoftpending;
    419 
    420 /*
    421  * Our ZS chips all share a common, autovectored interrupt,
    422  * so we have to look at all of them on each interrupt.
    423  */
    424 static int
    425 zshard(arg)
    426 	void *arg;
    427 {
    428 	struct zsc_softc *zsc;
    429 	int unit, rr3, rval, softreq;
    430 
    431 	rval = softreq = 0;
    432 	for (unit = 0; unit < zs_cd.cd_ndevs; unit++) {
    433 		struct zs_chanstate *cs;
    434 
    435 		zsc = zs_cd.cd_devs[unit];
    436 		if (zsc == NULL)
    437 			continue;
    438 		rr3 = zsc_intr_hard(zsc);
    439 		/* Count up the interrupts. */
    440 		if (rr3) {
    441 			rval |= rr3;
    442 			zsc->zsc_intrcnt.ev_count++;
    443 		}
    444 		if ((cs = zsc->zsc_cs[0]) != NULL)
    445 			softreq |= zsc->zsc_cs[0]->cs_softreq;
    446 		if ((cs = zsc->zsc_cs[1]) != NULL)
    447 			softreq |= zsc->zsc_cs[1]->cs_softreq;
    448 	}
    449 
    450 	/* We are at splzs here, so no need to lock. */
    451 	if (softreq && (zssoftpending == 0)) {
    452 		zssoftpending = PIL_TTY;
    453 		send_softint(-1, PIL_TTY, &levelsoft);
    454 	}
    455 	return (rval);
    456 }
    457 
    458 /*
    459  * Similar scheme as for zshard (look at all of them)
    460  */
    461 static int
    462 zssoft(arg)
    463 	void *arg;
    464 {
    465 	struct zsc_softc *zsc;
    466 	int s, unit;
    467 
    468 	/* This is not the only ISR on this IPL. */
    469 	if (zssoftpending == 0)
    470 		return (0);
    471 	zssoftpending = 0;
    472 
    473 	/* Make sure we call the tty layer at spltty. */
    474 	s = spltty();
    475 	for (unit = 0; unit < zs_cd.cd_ndevs; unit++) {
    476 		zsc = zs_cd.cd_devs[unit];
    477 		if (zsc == NULL)
    478 			continue;
    479 		(void)zsc_intr_soft(zsc);
    480 #ifdef TTY_DEBUG
    481 		{
    482 			struct zstty_softc *zst0 = zsc->zsc_cs[0]->cs_private;
    483 			struct zstty_softc *zst1 = zsc->zsc_cs[1]->cs_private;
    484 			if (zst0->zst_overflows || zst1->zst_overflows ) {
    485 				struct trapframe *frame = (struct trapframe *)arg;
    486 
    487 				printf("zs silo overflow from %p\n",
    488 				       (long)frame->tf_pc);
    489 			}
    490 		}
    491 #endif
    492 	}
    493 	splx(s);
    494 	return (1);
    495 }
    496 
    497 
    498 /*
    499  * Compute the current baud rate given a ZS channel.
    500  */
    501 static int
    502 zs_get_speed(cs)
    503 	struct zs_chanstate *cs;
    504 {
    505 	int tconst;
    506 
    507 	tconst = zs_read_reg(cs, 12);
    508 	tconst |= zs_read_reg(cs, 13) << 8;
    509 	return (TCONST_TO_BPS(cs->cs_brg_clk, tconst));
    510 }
    511 
    512 /*
    513  * MD functions for setting the baud rate and control modes.
    514  */
    515 int
    516 zs_set_speed(cs, bps)
    517 	struct zs_chanstate *cs;
    518 	int bps;	/* bits per second */
    519 {
    520 	int tconst, real_bps;
    521 
    522 	if (bps == 0)
    523 		return (0);
    524 
    525 #ifdef	DIAGNOSTIC
    526 	if (cs->cs_brg_clk == 0)
    527 		panic("zs_set_speed");
    528 #endif
    529 
    530 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
    531 	if (tconst < 0)
    532 		return (EINVAL);
    533 
    534 	/* Convert back to make sure we can do it. */
    535 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
    536 
    537 	/* XXX - Allow some tolerance here? */
    538 	if (real_bps != bps)
    539 		return (EINVAL);
    540 
    541 	cs->cs_preg[12] = tconst;
    542 	cs->cs_preg[13] = tconst >> 8;
    543 
    544 	/* Caller will stuff the pending registers. */
    545 	return (0);
    546 }
    547 
    548 int
    549 zs_set_modes(cs, cflag)
    550 	struct zs_chanstate *cs;
    551 	int cflag;	/* bits per second */
    552 {
    553 	int s;
    554 
    555 	/*
    556 	 * Output hardware flow control on the chip is horrendous:
    557 	 * if carrier detect drops, the receiver is disabled, and if
    558 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
    559 	 * Therefore, NEVER set the HFC bit, and instead use the
    560 	 * status interrupt to detect CTS changes.
    561 	 */
    562 	s = splzs();
    563 	cs->cs_rr0_pps = 0;
    564 	if ((cflag & (CLOCAL | MDMBUF)) != 0) {
    565 		cs->cs_rr0_dcd = 0;
    566 		if ((cflag & MDMBUF) == 0)
    567 			cs->cs_rr0_pps = ZSRR0_DCD;
    568 	} else
    569 		cs->cs_rr0_dcd = ZSRR0_DCD;
    570 	if ((cflag & CRTSCTS) != 0) {
    571 		cs->cs_wr5_dtr = ZSWR5_DTR;
    572 		cs->cs_wr5_rts = ZSWR5_RTS;
    573 		cs->cs_rr0_cts = ZSRR0_CTS;
    574 	} else if ((cflag & CDTRCTS) != 0) {
    575 		cs->cs_wr5_dtr = 0;
    576 		cs->cs_wr5_rts = ZSWR5_DTR;
    577 		cs->cs_rr0_cts = ZSRR0_CTS;
    578 	} else if ((cflag & MDMBUF) != 0) {
    579 		cs->cs_wr5_dtr = 0;
    580 		cs->cs_wr5_rts = ZSWR5_DTR;
    581 		cs->cs_rr0_cts = ZSRR0_DCD;
    582 	} else {
    583 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
    584 		cs->cs_wr5_rts = 0;
    585 		cs->cs_rr0_cts = 0;
    586 	}
    587 	splx(s);
    588 
    589 	/* Caller will stuff the pending registers. */
    590 	return (0);
    591 }
    592 
    593 
    594 /*
    595  * Read or write the chip with suitable delays.
    596  */
    597 
    598 u_char
    599 zs_read_reg(cs, reg)
    600 	struct zs_chanstate *cs;
    601 	u_char reg;
    602 {
    603 	u_char val;
    604 
    605 	*cs->cs_reg_csr = reg;
    606 	ZS_DELAY();
    607 	val = *cs->cs_reg_csr;
    608 	ZS_DELAY();
    609 	return (val);
    610 }
    611 
    612 void
    613 zs_write_reg(cs, reg, val)
    614 	struct zs_chanstate *cs;
    615 	u_char reg, val;
    616 {
    617 	*cs->cs_reg_csr = reg;
    618 	ZS_DELAY();
    619 	*cs->cs_reg_csr = val;
    620 	ZS_DELAY();
    621 }
    622 
    623 u_char
    624 zs_read_csr(cs)
    625 	struct zs_chanstate *cs;
    626 {
    627 	u_char val;
    628 
    629 	val = *cs->cs_reg_csr;
    630 	ZS_DELAY();
    631 	return (val);
    632 }
    633 
    634 void  zs_write_csr(cs, val)
    635 	struct zs_chanstate *cs;
    636 	u_char val;
    637 {
    638 	*cs->cs_reg_csr = val;
    639 	ZS_DELAY();
    640 }
    641 
    642 u_char zs_read_data(cs)
    643 	struct zs_chanstate *cs;
    644 {
    645 	u_char val;
    646 
    647 	val = *cs->cs_reg_data;
    648 	ZS_DELAY();
    649 	return (val);
    650 }
    651 
    652 void  zs_write_data(cs, val)
    653 	struct zs_chanstate *cs;
    654 	u_char val;
    655 {
    656 	*cs->cs_reg_data = val;
    657 	ZS_DELAY();
    658 }
    659 
    660 /****************************************************************
    661  * Console support functions (Sun specific!)
    662  * Note: this code is allowed to know about the layout of
    663  * the chip registers, and uses that to keep things simple.
    664  * XXX - I think I like the mvme167 code better. -gwr
    665  ****************************************************************/
    666 
    667 extern void Debugger __P((void));
    668 
    669 /*
    670  * Handle user request to enter kernel debugger.
    671  */
    672 void
    673 zs_abort(cs)
    674 	struct zs_chanstate *cs;
    675 {
    676 	volatile struct zschan *zc = zs_conschan_get;
    677 	int rr0;
    678 
    679 	/* Wait for end of break to avoid PROM abort. */
    680 	/* XXX - Limit the wait? */
    681 	do {
    682 		rr0 = zc->zc_csr;
    683 		ZS_DELAY();
    684 	} while (rr0 & ZSRR0_BREAK);
    685 
    686 #if defined(KGDB)
    687 	zskgdb(cs);
    688 #elif defined(DDB)
    689 	{
    690 		extern int db_active;
    691 
    692 		if (!db_active)
    693 			Debugger();
    694 		else
    695 			/* Debugger is probably hozed */
    696 			callrom();
    697 	}
    698 #else
    699 	printf("stopping on keyboard abort\n");
    700 	callrom();
    701 #endif
    702 }
    703 
    704 
    705 /*
    706  * Polled input char.
    707  */
    708 int
    709 zs_getc(arg)
    710 	void *arg;
    711 {
    712 	volatile struct zschan *zc = arg;
    713 	int s, c, rr0;
    714 
    715 	s = splhigh();
    716 	/* Wait for a character to arrive. */
    717 	do {
    718 		rr0 = zc->zc_csr;
    719 		ZS_DELAY();
    720 	} while ((rr0 & ZSRR0_RX_READY) == 0);
    721 
    722 	c = zc->zc_data;
    723 	ZS_DELAY();
    724 	splx(s);
    725 
    726 	/*
    727 	 * This is used by the kd driver to read scan codes,
    728 	 * so don't translate '\r' ==> '\n' here...
    729 	 */
    730 	return (c);
    731 }
    732 
    733 /*
    734  * Polled output char.
    735  */
    736 void
    737 zs_putc(arg, c)
    738 	void *arg;
    739 	int c;
    740 {
    741 	volatile struct zschan *zc = arg;
    742 	int s, rr0;
    743 
    744 	s = splhigh();
    745 
    746 	/* Wait for transmitter to become ready. */
    747 	do {
    748 		rr0 = zc->zc_csr;
    749 		ZS_DELAY();
    750 	} while ((rr0 & ZSRR0_TX_READY) == 0);
    751 
    752 	/*
    753 	 * Send the next character.
    754 	 * Now you'd think that this could be followed by a ZS_DELAY()
    755 	 * just like all the other chip accesses, but it turns out that
    756 	 * the `transmit-ready' interrupt isn't de-asserted until
    757 	 * some period of time after the register write completes
    758 	 * (more than a couple instructions).  So to avoid stray
    759 	 * interrupts we put in the 2us delay regardless of cpu model.
    760 	 */
    761 	zc->zc_data = c;
    762 	delay(2);
    763 
    764 	splx(s);
    765 }
    766 
    767 /*****************************************************************/
    768 
    769 
    770 
    771 
    772 /*
    773  * Polled console input putchar.
    774  */
    775 static int
    776 zscngetc(dev)
    777 	dev_t dev;
    778 {
    779 	return (zs_getc(zs_conschan_get));
    780 }
    781 
    782 /*
    783  * Polled console output putchar.
    784  */
    785 static void
    786 zscnputc(dev, c)
    787 	dev_t dev;
    788 	int c;
    789 {
    790 	zs_putc(zs_conschan_put, c);
    791 }
    792 
    793 int swallow_zsintrs;
    794 
    795 static void
    796 zscnpollc(dev, on)
    797 	dev_t dev;
    798 	int on;
    799 {
    800 	/*
    801 	 * Need to tell zs driver to acknowledge all interrupts or we get
    802 	 * annoying spurious interrupt messages.  This is because mucking
    803 	 * with spl() levels during polling does not prevent interrupts from
    804 	 * being generated.
    805 	 */
    806 
    807 	if (on) swallow_zsintrs++;
    808 	else swallow_zsintrs--;
    809 }
    810 
    811 int
    812 zs_console_flags(promunit, node, channel)
    813 	int promunit;
    814 	int node;
    815 	int channel;
    816 {
    817 	int cookie, flags = 0;
    818 	u_int chosen;
    819 	char buf[255];
    820 
    821 	/*
    822 	 * We'll just to the OBP grovelling down here since that's
    823 	 * the only type of firmware we support.
    824 	 */
    825 	chosen = OF_finddevice("/chosen");
    826 
    827 	/* Default to channel 0 if there are no explicit prom args */
    828 	cookie = 0;
    829 	if (node == OF_instance_to_package(OF_stdin())) {
    830 		if (OF_getprop(chosen, "input-device", buf, sizeof(buf)) != -1) {
    831 
    832 			if (!strcmp("ttyb", buf))
    833 				cookie = 1;
    834 		}
    835 
    836 		if (channel == cookie)
    837 			flags |= ZS_HWFLAG_CONSOLE_INPUT;
    838 	}
    839 
    840 	if (node == OF_instance_to_package(OF_stdout())) {
    841 		if (OF_getprop(chosen, "output-device", buf, sizeof(buf)) != -1) {
    842 
    843 			if (!strcmp("ttyb", buf))
    844 				cookie = 1;
    845 		}
    846 
    847 		if (channel == cookie)
    848 			flags |= ZS_HWFLAG_CONSOLE_OUTPUT;
    849 	}
    850 
    851 	return (flags);
    852 }
    853 
    854