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zs.c revision 1.62.34.2
      1 /*	$NetBSD: zs.c,v 1.62.34.2 2007/12/08 18:17:57 mjf 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 <sys/cdefs.h>
     48 __KERNEL_RCSID(0, "$NetBSD: zs.c,v 1.62.34.2 2007/12/08 18:17:57 mjf Exp $");
     49 
     50 #include "opt_ddb.h"
     51 #include "opt_kgdb.h"
     52 
     53 #include <sys/param.h>
     54 #include <sys/systm.h>
     55 #include <sys/conf.h>
     56 #include <sys/device.h>
     57 #include <sys/file.h>
     58 #include <sys/ioctl.h>
     59 #include <sys/kernel.h>
     60 #include <sys/proc.h>
     61 #include <sys/tty.h>
     62 #include <sys/time.h>
     63 #include <sys/syslog.h>
     64 #include <sys/intr.h>
     65 
     66 #include <machine/autoconf.h>
     67 #include <machine/openfirm.h>
     68 #include <machine/cpu.h>
     69 #include <machine/eeprom.h>
     70 #include <machine/psl.h>
     71 #include <machine/z8530var.h>
     72 
     73 #include <dev/cons.h>
     74 #include <dev/ic/z8530reg.h>
     75 #include <dev/sun/kbd_ms_ttyvar.h>
     76 #include <ddb/db_output.h>
     77 
     78 #include <sparc64/dev/cons.h>
     79 
     80 #include "kbd.h"	/* NKBD */
     81 #include "ms.h"		/* NMS */
     82 #include "zs.h" 	/* NZS */
     83 
     84 /* Make life easier for the initialized arrays here. */
     85 #if NZS < 3
     86 #undef  NZS
     87 #define NZS 3
     88 #endif
     89 
     90 /*
     91  * Some warts needed by z8530tty.c -
     92  * The default parity REALLY needs to be the same as the PROM uses,
     93  * or you can not see messages done with printf during boot-up...
     94  */
     95 int zs_def_cflag = (CREAD | CS8 | HUPCL);
     96 
     97 /*
     98  * The Sun provides a 4.9152 MHz clock to the ZS chips.
     99  */
    100 #define PCLK	(9600 * 512)	/* PCLK pin input clock rate */
    101 
    102 #define	ZS_DELAY()
    103 
    104 /* The layout of this is hardware-dependent (padding, order). */
    105 struct zschan {
    106 	volatile u_char	zc_csr;		/* ctrl,status, and indirect access */
    107 	u_char		zc_xxx0;
    108 	volatile u_char	zc_data;	/* data */
    109 	u_char		zc_xxx1;
    110 };
    111 struct zsdevice {
    112 	/* Yes, they are backwards. */
    113 	struct	zschan zs_chan_b;
    114 	struct	zschan zs_chan_a;
    115 };
    116 
    117 /* ZS channel used as the console device (if any) */
    118 void *zs_conschan_get, *zs_conschan_put;
    119 
    120 /* Saved PROM mappings */
    121 static struct zsdevice *zsaddr[NZS];
    122 
    123 static u_char zs_init_reg[16] = {
    124 	0,	/* 0: CMD (reset, etc.) */
    125 	0,	/* 1: No interrupts yet. */
    126 	0,	/* 2: IVECT */
    127 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
    128 	ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
    129 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
    130 	0,	/* 6: TXSYNC/SYNCLO */
    131 	0,	/* 7: RXSYNC/SYNCHI */
    132 	0,	/* 8: alias for data port */
    133 	ZSWR9_MASTER_IE | ZSWR9_NO_VECTOR,
    134 	0,	/*10: Misc. TX/RX control bits */
    135 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
    136 	((PCLK/32)/9600)-2,	/*12: BAUDLO (default=9600) */
    137 	0,			/*13: BAUDHI (default=9600) */
    138 	ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
    139 	ZSWR15_BREAK_IE,
    140 };
    141 
    142 /* Console ops */
    143 static int  zscngetc(dev_t);
    144 static void zscnputc(dev_t, int);
    145 static void zscnpollc(dev_t, int);
    146 
    147 struct consdev zs_consdev = {
    148 	.cn_getc = zscngetc,
    149 	.cn_putc = zscnputc,
    150 	.cn_pollc = zscnpollc,
    151 };
    152 
    153 
    154 /****************************************************************
    155  * Autoconfig
    156  ****************************************************************/
    157 
    158 /* Definition of the driver for autoconfig. */
    159 static int  zs_match_sbus(struct device *, struct cfdata *, void *);
    160 static void zs_attach_sbus(struct device *, struct device *, void *);
    161 
    162 static void zs_attach(struct zsc_softc *, struct zsdevice *, int);
    163 static int  zs_print(void *, const char *);
    164 
    165 CFATTACH_DECL(zs, sizeof(struct zsc_softc),
    166     zs_match_sbus, zs_attach_sbus, NULL, NULL);
    167 
    168 extern struct cfdriver zs_cd;
    169 
    170 /* Interrupt handlers. */
    171 int zscheckintr(void *);
    172 static int zshard(void *);
    173 static void zssoft(void *);
    174 
    175 static int zs_get_speed(struct zs_chanstate *);
    176 
    177 /* Console device support */
    178 static int zs_console_flags(int, int, int);
    179 
    180 /* Power management hooks */
    181 int  zs_enable(struct zs_chanstate *);
    182 void zs_disable(struct zs_chanstate *);
    183 
    184 /* from dev/ic/z8530tty.c */
    185 struct tty *zstty_get_tty_from_dev(struct device *);
    186 
    187 /*
    188  * Is the zs chip present?
    189  */
    190 static int
    191 zs_match_sbus(struct device *parent, struct cfdata *cf, void *aux)
    192 {
    193 	struct sbus_attach_args *sa = aux;
    194 
    195 	if (strcmp(cf->cf_name, sa->sa_name) != 0)
    196 		return (0);
    197 
    198 	return (1);
    199 }
    200 
    201 static void
    202 zs_attach_sbus(struct device *parent, struct device *self, void *aux)
    203 {
    204 	struct zsc_softc *zsc = (void *) self;
    205 	struct sbus_attach_args *sa = aux;
    206 	bus_space_handle_t bh;
    207 	int zs_unit = device_unit(&zsc->zsc_dev);
    208 
    209 	if (sa->sa_nintr == 0) {
    210 		printf(" no interrupt lines\n");
    211 		return;
    212 	}
    213 
    214 	/* Use the mapping setup by the Sun PROM if possible. */
    215 	if (zsaddr[zs_unit] == NULL) {
    216 		/* Only map registers once. */
    217 		if (sa->sa_npromvaddrs) {
    218 			/*
    219 			 * We're converting from a 32-bit pointer to a 64-bit
    220 			 * pointer.  Since the 32-bit entity is negative, but
    221 			 * the kernel is still mapped into the lower 4GB
    222 			 * range, this needs to be zero-extended.
    223 			 *
    224 			 * XXXXX If we map the kernel and devices into the
    225 			 * high 4GB range, this needs to be changed to
    226 			 * sign-extend the address.
    227 			 */
    228 			sparc_promaddr_to_handle(sa->sa_bustag,
    229 				sa->sa_promvaddrs[0], &bh);
    230 
    231 		} else {
    232 
    233 			if (sbus_bus_map(sa->sa_bustag, sa->sa_slot,
    234 					 sa->sa_offset,
    235 					 sa->sa_size,
    236 					 BUS_SPACE_MAP_LINEAR,
    237 					 &bh) != 0) {
    238 				printf("%s @ sbus: cannot map registers\n",
    239 				       self->dv_xname);
    240 				return;
    241 			}
    242 		}
    243 		zsaddr[zs_unit] = (struct zsdevice *)
    244 			bus_space_vaddr(sa->sa_bustag, bh);
    245 	}
    246 	zsc->zsc_bustag = sa->sa_bustag;
    247 	zsc->zsc_dmatag = sa->sa_dmatag;
    248 	zsc->zsc_promunit = prom_getpropint(sa->sa_node, "slave", -2);
    249 	zsc->zsc_node = sa->sa_node;
    250 	zs_attach(zsc, zsaddr[zs_unit], sa->sa_pri);
    251 }
    252 
    253 /*
    254  * Attach a found zs.
    255  *
    256  * USE ROM PROPERTIES port-a-ignore-cd AND port-b-ignore-cd FOR
    257  * SOFT CARRIER, AND keyboard PROPERTY FOR KEYBOARD/MOUSE?
    258  */
    259 static void
    260 zs_attach(struct zsc_softc *zsc, struct zsdevice *zsd, int pri)
    261 {
    262 	struct zsc_attach_args zsc_args;
    263 	struct zs_chanstate *cs;
    264 	int s, channel;
    265 
    266 	if (zsd == NULL) {
    267 		printf("configuration incomplete\n");
    268 		return;
    269 	}
    270 
    271 	/*
    272 	 * Initialize software state for each channel.
    273 	 */
    274 	for (channel = 0; channel < 2; channel++) {
    275 		struct zschan *zc;
    276 		struct device *child;
    277 
    278 		zsc_args.channel = channel;
    279 		cs = &zsc->zsc_cs_store[channel];
    280 		zsc->zsc_cs[channel] = cs;
    281 
    282 		zs_lock_init(cs);
    283 		cs->cs_channel = channel;
    284 		cs->cs_private = NULL;
    285 		cs->cs_ops = &zsops_null;
    286 		cs->cs_brg_clk = PCLK / 16;
    287 
    288 		zc = (channel == 0) ? &zsd->zs_chan_a : &zsd->zs_chan_b;
    289 
    290 		zsc_args.consdev = NULL;
    291 		zsc_args.hwflags = zs_console_flags(zsc->zsc_promunit,
    292 						    zsc->zsc_node,
    293 						    channel);
    294 
    295 		if (zsc_args.hwflags & ZS_HWFLAG_CONSOLE) {
    296 			zsc_args.hwflags |= ZS_HWFLAG_USE_CONSDEV;
    297 			zsc_args.consdev = &zs_consdev;
    298 		}
    299 
    300 		if ((zsc_args.hwflags & ZS_HWFLAG_CONSOLE_INPUT) != 0) {
    301 			zs_conschan_get = zc;
    302 		}
    303 		if ((zsc_args.hwflags & ZS_HWFLAG_CONSOLE_OUTPUT) != 0) {
    304 			zs_conschan_put = zc;
    305 		}
    306 
    307 		/* Children need to set cn_dev, etc */
    308 		cs->cs_reg_csr  = &zc->zc_csr;
    309 		cs->cs_reg_data = &zc->zc_data;
    310 
    311 		memcpy(cs->cs_creg, zs_init_reg, 16);
    312 		memcpy(cs->cs_preg, zs_init_reg, 16);
    313 
    314 		/* XXX: Consult PROM properties for this?! */
    315 		cs->cs_defspeed = zs_get_speed(cs);
    316 		cs->cs_defcflag = zs_def_cflag;
    317 
    318 		/* Make these correspond to cs_defcflag (-crtscts) */
    319 		cs->cs_rr0_dcd = ZSRR0_DCD;
    320 		cs->cs_rr0_cts = 0;
    321 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
    322 		cs->cs_wr5_rts = 0;
    323 
    324 		/*
    325 		 * Clear the master interrupt enable.
    326 		 * The INTENA is common to both channels,
    327 		 * so just do it on the A channel.
    328 		 */
    329 		if (channel == 0) {
    330 			zs_write_reg(cs, 9, 0);
    331 		}
    332 
    333 		/*
    334 		 * Look for a child driver for this channel.
    335 		 * The child attach will setup the hardware.
    336 		 */
    337 		child = config_found(&zsc->zsc_dev, (void *)&zsc_args,
    338 		    zs_print);
    339 		if (child == NULL) {
    340 			/* No sub-driver.  Just reset it. */
    341 			u_char reset = (channel == 0) ?
    342 				ZSWR9_A_RESET : ZSWR9_B_RESET;
    343 			s = splzs();
    344 			zs_write_reg(cs,  9, reset);
    345 			splx(s);
    346 		}
    347 #if (NKBD > 0) || (NMS > 0)
    348 		/*
    349 		 * If this was a zstty it has a keyboard
    350 		 * property on it we need to attach the
    351 		 * sunkbd and sunms line disciplines.
    352 		 */
    353 		if (child
    354 		    && (device_is_a(child, "zstty"))
    355 		    && (prom_getproplen(zsc->zsc_node, "keyboard") == 0)) {
    356 			struct kbd_ms_tty_attach_args kma;
    357 			struct tty *tp;
    358 
    359 			kma.kmta_tp = tp = zstty_get_tty_from_dev(child);
    360 			kma.kmta_dev = tp->t_dev;
    361 			kma.kmta_consdev = zsc_args.consdev;
    362 
    363 			/* Attach 'em if we got 'em. */
    364 #if (NKBD > 0)
    365 			if (channel == 0) {
    366 				kma.kmta_name = "keyboard";
    367 				config_found(child, (void *)&kma, NULL);
    368 			}
    369 #endif
    370 #if (NMS > 0)
    371 			if (channel == 1) {
    372 				kma.kmta_name = "mouse";
    373 				config_found(child, (void *)&kma, NULL);
    374 			}
    375 #endif
    376 		}
    377 #endif
    378 	}
    379 
    380 	/*
    381 	 * Now safe to install interrupt handlers.  Note the arguments
    382 	 * to the interrupt handlers aren't used.  Note, we only do this
    383 	 * once since both SCCs interrupt at the same level and vector.
    384 	 */
    385 	bus_intr_establish(zsc->zsc_bustag, pri, IPL_SERIAL, zshard, zsc);
    386 	if (!(zsc->zsc_softintr = softint_establish(SOFTINT_SERIAL, zssoft, zsc)))
    387 		panic("zsattach: could not establish soft interrupt");
    388 
    389 	evcnt_attach_dynamic(&zsc->zsc_intrcnt, EVCNT_TYPE_INTR, NULL,
    390 	    zsc->zsc_dev.dv_xname, "intr");
    391 
    392 
    393 	/*
    394 	 * Set the master interrupt enable and interrupt vector.
    395 	 * (common to both channels, do it on A)
    396 	 */
    397 	cs = zsc->zsc_cs[0];
    398 	s = splhigh();
    399 	/* interrupt vector */
    400 	zs_write_reg(cs, 2, zs_init_reg[2]);
    401 	/* master interrupt control (enable) */
    402 	zs_write_reg(cs, 9, zs_init_reg[9]);
    403 	splx(s);
    404 
    405 }
    406 
    407 static int
    408 zs_print(void *aux, const char *name)
    409 {
    410 	struct zsc_attach_args *args = aux;
    411 
    412 	if (name != NULL)
    413 		aprint_normal("%s: ", name);
    414 
    415 	if (args->channel != -1)
    416 		aprint_normal(" channel %d", args->channel);
    417 
    418 	return (UNCONF);
    419 }
    420 
    421 /* Deprecate this? */
    422 static volatile int zssoftpending;
    423 
    424 static int
    425 zshard(void *arg)
    426 {
    427 	struct zsc_softc *zsc = (struct zsc_softc *)arg;
    428 	int rr3, rval;
    429 
    430 	rval = 0;
    431 	while ((rr3 = zsc_intr_hard(zsc))) {
    432 		/* Count up the interrupts. */
    433 		rval |= rr3;
    434 		zsc->zsc_intrcnt.ev_count++;
    435 	}
    436 	if (((zsc->zsc_cs[0] && zsc->zsc_cs[0]->cs_softreq) ||
    437 	     (zsc->zsc_cs[1] && zsc->zsc_cs[1]->cs_softreq)) &&
    438 	    zsc->zsc_softintr) {
    439 		zssoftpending = PIL_TTY;
    440 		softint_schedule(zsc->zsc_softintr);
    441 	}
    442 	return (rval);
    443 }
    444 
    445 int
    446 zscheckintr(void *arg)
    447 {
    448 	struct zsc_softc *zsc;
    449 	int unit, rval;
    450 
    451 	rval = 0;
    452 	for (unit = 0; unit < zs_cd.cd_ndevs; unit++) {
    453 
    454 		zsc = zs_cd.cd_devs[unit];
    455 		if (zsc == NULL)
    456 			continue;
    457 		rval = (zshard((void *)zsc) || rval);
    458 	}
    459 	return (rval);
    460 }
    461 
    462 
    463 /*
    464  * We need this only for TTY_DEBUG purposes.
    465  */
    466 static void
    467 zssoft(void *arg)
    468 {
    469 	struct zsc_softc *zsc = (struct zsc_softc *)arg;
    470 	int s;
    471 
    472 	/* Make sure we call the tty layer at spltty. */
    473 	s = spltty();
    474 	zssoftpending = 0;
    475 	(void)zsc_intr_soft(zsc);
    476 #ifdef TTY_DEBUG
    477 	{
    478 		struct zstty_softc *zst0 = zsc->zsc_cs[0]->cs_private;
    479 		struct zstty_softc *zst1 = zsc->zsc_cs[1]->cs_private;
    480 		if (zst0->zst_overflows || zst1->zst_overflows ) {
    481 			struct trapframe *frame = (struct trapframe *)arg;
    482 
    483 			printf("zs silo overflow from %p\n",
    484 			       (long)frame->tf_pc);
    485 		}
    486 	}
    487 #endif
    488 	splx(s);
    489 }
    490 
    491 
    492 /*
    493  * Compute the current baud rate given a ZS channel.
    494  */
    495 static int
    496 zs_get_speed(struct zs_chanstate *cs)
    497 {
    498 	int tconst;
    499 
    500 	tconst = zs_read_reg(cs, 12);
    501 	tconst |= zs_read_reg(cs, 13) << 8;
    502 	return (TCONST_TO_BPS(cs->cs_brg_clk, tconst));
    503 }
    504 
    505 /*
    506  * MD functions for setting the baud rate and control modes.
    507  */
    508 int
    509 zs_set_speed(struct zs_chanstate *cs, int bps /* bits per second */)
    510 {
    511 	int tconst, real_bps;
    512 
    513 	if (bps == 0)
    514 		return (0);
    515 
    516 #ifdef	DIAGNOSTIC
    517 	if (cs->cs_brg_clk == 0)
    518 		panic("zs_set_speed");
    519 #endif
    520 
    521 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
    522 	if (tconst < 0)
    523 		return (EINVAL);
    524 
    525 	/* Convert back to make sure we can do it. */
    526 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
    527 
    528 	/* XXX - Allow some tolerance here? */
    529 	if (real_bps != bps)
    530 		return (EINVAL);
    531 
    532 	cs->cs_preg[12] = tconst;
    533 	cs->cs_preg[13] = tconst >> 8;
    534 
    535 	/* Caller will stuff the pending registers. */
    536 	return (0);
    537 }
    538 
    539 int
    540 zs_set_modes(struct zs_chanstate *cs, int cflag)
    541 {
    542 	int s;
    543 
    544 	/*
    545 	 * Output hardware flow control on the chip is horrendous:
    546 	 * if carrier detect drops, the receiver is disabled, and if
    547 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
    548 	 * Therefore, NEVER set the HFC bit, and instead use the
    549 	 * status interrupt to detect CTS changes.
    550 	 */
    551 	s = splzs();
    552 	cs->cs_rr0_pps = 0;
    553 	if ((cflag & (CLOCAL | MDMBUF)) != 0) {
    554 		cs->cs_rr0_dcd = 0;
    555 		if ((cflag & MDMBUF) == 0)
    556 			cs->cs_rr0_pps = ZSRR0_DCD;
    557 	} else
    558 		cs->cs_rr0_dcd = ZSRR0_DCD;
    559 	if ((cflag & CRTSCTS) != 0) {
    560 		cs->cs_wr5_dtr = ZSWR5_DTR;
    561 		cs->cs_wr5_rts = ZSWR5_RTS;
    562 		cs->cs_rr0_cts = ZSRR0_CTS;
    563 	} else if ((cflag & CDTRCTS) != 0) {
    564 		cs->cs_wr5_dtr = 0;
    565 		cs->cs_wr5_rts = ZSWR5_DTR;
    566 		cs->cs_rr0_cts = ZSRR0_CTS;
    567 	} else if ((cflag & MDMBUF) != 0) {
    568 		cs->cs_wr5_dtr = 0;
    569 		cs->cs_wr5_rts = ZSWR5_DTR;
    570 		cs->cs_rr0_cts = ZSRR0_DCD;
    571 	} else {
    572 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
    573 		cs->cs_wr5_rts = 0;
    574 		cs->cs_rr0_cts = 0;
    575 	}
    576 	splx(s);
    577 
    578 	/* Caller will stuff the pending registers. */
    579 	return (0);
    580 }
    581 
    582 
    583 /*
    584  * Read or write the chip with suitable delays.
    585  */
    586 
    587 u_char
    588 zs_read_reg(struct zs_chanstate *cs, u_char reg)
    589 {
    590 	u_char val;
    591 
    592 	*cs->cs_reg_csr = reg;
    593 	ZS_DELAY();
    594 	val = *cs->cs_reg_csr;
    595 	ZS_DELAY();
    596 	return (val);
    597 }
    598 
    599 void
    600 zs_write_reg(struct zs_chanstate *cs, u_char reg, u_char val)
    601 {
    602 	*cs->cs_reg_csr = reg;
    603 	ZS_DELAY();
    604 	*cs->cs_reg_csr = val;
    605 	ZS_DELAY();
    606 }
    607 
    608 u_char
    609 zs_read_csr(struct zs_chanstate *cs)
    610 {
    611 	u_char val;
    612 
    613 	val = *cs->cs_reg_csr;
    614 	ZS_DELAY();
    615 	return (val);
    616 }
    617 
    618 void
    619 zs_write_csr(struct zs_chanstate *cs, u_char val)
    620 {
    621 	*cs->cs_reg_csr = val;
    622 	ZS_DELAY();
    623 }
    624 
    625 u_char
    626 zs_read_data(struct zs_chanstate *cs)
    627 {
    628 	u_char val;
    629 
    630 	val = *cs->cs_reg_data;
    631 	ZS_DELAY();
    632 	return (val);
    633 }
    634 
    635 void
    636 zs_write_data(struct zs_chanstate *cs, u_char val)
    637 {
    638 	*cs->cs_reg_data = val;
    639 	ZS_DELAY();
    640 }
    641 
    642 /****************************************************************
    643  * Console support functions (Sun specific!)
    644  * Note: this code is allowed to know about the layout of
    645  * the chip registers, and uses that to keep things simple.
    646  * XXX - I think I like the mvme167 code better. -gwr
    647  ****************************************************************/
    648 
    649 extern void Debugger(void);
    650 
    651 /*
    652  * Handle user request to enter kernel debugger.
    653  */
    654 void
    655 zs_abort(struct zs_chanstate *cs)
    656 {
    657 	volatile struct zschan *zc = zs_conschan_get;
    658 	int rr0;
    659 
    660 	/* Wait for end of break to avoid PROM abort. */
    661 	/* XXX - Limit the wait? */
    662 	do {
    663 		rr0 = zc->zc_csr;
    664 		ZS_DELAY();
    665 	} while (rr0 & ZSRR0_BREAK);
    666 
    667 #if defined(KGDB)
    668 	zskgdb(cs);
    669 #elif defined(DDB)
    670 	{
    671 		extern int db_active;
    672 
    673 		if (!db_active)
    674 			Debugger();
    675 		else
    676 			/* Debugger is probably hozed */
    677 			callrom();
    678 	}
    679 #else
    680 	printf("stopping on keyboard abort\n");
    681 	callrom();
    682 #endif
    683 }
    684 
    685 
    686 /*
    687  * Polled input char.
    688  */
    689 int
    690 zs_getc(void *arg)
    691 {
    692 	volatile struct zschan *zc = arg;
    693 	int s, c, rr0;
    694 
    695 	s = splhigh();
    696 	/* Wait for a character to arrive. */
    697 	do {
    698 		rr0 = zc->zc_csr;
    699 		ZS_DELAY();
    700 	} while ((rr0 & ZSRR0_RX_READY) == 0);
    701 
    702 	c = zc->zc_data;
    703 	ZS_DELAY();
    704 	splx(s);
    705 
    706 	/*
    707 	 * This is used by the kd driver to read scan codes,
    708 	 * so don't translate '\r' ==> '\n' here...
    709 	 */
    710 	return (c);
    711 }
    712 
    713 /*
    714  * Polled output char.
    715  */
    716 void
    717 zs_putc(void *arg, int c)
    718 {
    719 	volatile struct zschan *zc = arg;
    720 	int s, rr0;
    721 
    722 	s = splhigh();
    723 
    724 	/* Wait for transmitter to become ready. */
    725 	do {
    726 		rr0 = zc->zc_csr;
    727 		ZS_DELAY();
    728 	} while ((rr0 & ZSRR0_TX_READY) == 0);
    729 
    730 	/*
    731 	 * Send the next character.
    732 	 * Now you'd think that this could be followed by a ZS_DELAY()
    733 	 * just like all the other chip accesses, but it turns out that
    734 	 * the `transmit-ready' interrupt isn't de-asserted until
    735 	 * some period of time after the register write completes
    736 	 * (more than a couple instructions).  So to avoid stray
    737 	 * interrupts we put in the 2us delay regardless of CPU model.
    738 	 */
    739 	zc->zc_data = c;
    740 	delay(2);
    741 
    742 	splx(s);
    743 }
    744 
    745 /*****************************************************************/
    746 
    747 
    748 
    749 
    750 /*
    751  * Polled console input putchar.
    752  */
    753 static int
    754 zscngetc(dev_t dev)
    755 {
    756 	return (zs_getc(zs_conschan_get));
    757 }
    758 
    759 /*
    760  * Polled console output putchar.
    761  */
    762 static void
    763 zscnputc(dev_t dev, int c)
    764 {
    765 	zs_putc(zs_conschan_put, c);
    766 }
    767 
    768 int swallow_zsintrs;
    769 
    770 static void
    771 zscnpollc(dev_t dev, int on)
    772 {
    773 	/*
    774 	 * Need to tell zs driver to acknowledge all interrupts or we get
    775 	 * annoying spurious interrupt messages.  This is because mucking
    776 	 * with spl() levels during polling does not prevent interrupts from
    777 	 * being generated.
    778 	 */
    779 
    780 	if (on) swallow_zsintrs++;
    781 	else swallow_zsintrs--;
    782 }
    783 
    784 int
    785 zs_console_flags(int promunit, int node, int channel)
    786 {
    787 	int cookie, flags = 0;
    788 	char buf[255];
    789 
    790 	/*
    791 	 * We'll just do the OBP grovelling down here since that's
    792 	 * the only type of firmware we support.
    793 	 */
    794 
    795 	/* Default to channel 0 if there are no explicit prom args */
    796 	cookie = 0;
    797 	if (node == prom_instance_to_package(prom_stdin())) {
    798 		if (prom_getoption("input-device", buf, sizeof buf) == 0 &&
    799 		    strcmp("ttyb", buf) == 0)
    800 			cookie = 1;
    801 
    802 		if (channel == cookie)
    803 			flags |= ZS_HWFLAG_CONSOLE_INPUT;
    804 	}
    805 
    806 	if (node == prom_instance_to_package(prom_stdout())) {
    807 		if (prom_getoption("output-device", buf, sizeof buf) == 0 &&
    808 		    strcmp("ttyb", buf) == 0)
    809 			cookie = 1;
    810 
    811 		if (channel == cookie)
    812 			flags |= ZS_HWFLAG_CONSOLE_OUTPUT;
    813 	}
    814 
    815 	return (flags);
    816 }
    817 
    818