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zs.c revision 1.63
      1 /*	$NetBSD: zs.c,v 1.63 2007/11/09 00:05:06 ad 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 1.63 2007/11/09 00:05:06 ad 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 
     65 #include <machine/autoconf.h>
     66 #include <machine/openfirm.h>
     67 #include <machine/cpu.h>
     68 #include <machine/eeprom.h>
     69 #include <machine/psl.h>
     70 #include <machine/z8530var.h>
     71 
     72 #include <dev/cons.h>
     73 #include <dev/ic/z8530reg.h>
     74 #include <dev/sun/kbd_ms_ttyvar.h>
     75 #include <ddb/db_output.h>
     76 
     77 #include <sparc64/dev/cons.h>
     78 
     79 #include "kbd.h"	/* NKBD */
     80 #include "ms.h"		/* NMS */
     81 #include "zs.h" 	/* NZS */
     82 
     83 /* Make life easier for the initialized arrays here. */
     84 #if NZS < 3
     85 #undef  NZS
     86 #define NZS 3
     87 #endif
     88 
     89 /*
     90  * Some warts needed by z8530tty.c -
     91  * The default parity REALLY needs to be the same as the PROM uses,
     92  * or you can not see messages done with printf during boot-up...
     93  */
     94 int zs_def_cflag = (CREAD | CS8 | HUPCL);
     95 
     96 /*
     97  * The Sun provides a 4.9152 MHz clock to the ZS chips.
     98  */
     99 #define PCLK	(9600 * 512)	/* PCLK pin input clock rate */
    100 
    101 #define	ZS_DELAY()
    102 
    103 /* The layout of this is hardware-dependent (padding, order). */
    104 struct zschan {
    105 	volatile u_char	zc_csr;		/* ctrl,status, and indirect access */
    106 	u_char		zc_xxx0;
    107 	volatile u_char	zc_data;	/* data */
    108 	u_char		zc_xxx1;
    109 };
    110 struct zsdevice {
    111 	/* Yes, they are backwards. */
    112 	struct	zschan zs_chan_b;
    113 	struct	zschan zs_chan_a;
    114 };
    115 
    116 /* ZS channel used as the console device (if any) */
    117 void *zs_conschan_get, *zs_conschan_put;
    118 
    119 /* Saved PROM mappings */
    120 static struct zsdevice *zsaddr[NZS];
    121 
    122 static u_char zs_init_reg[16] = {
    123 	0,	/* 0: CMD (reset, etc.) */
    124 	0,	/* 1: No interrupts yet. */
    125 	0,	/* 2: IVECT */
    126 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
    127 	ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
    128 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
    129 	0,	/* 6: TXSYNC/SYNCLO */
    130 	0,	/* 7: RXSYNC/SYNCHI */
    131 	0,	/* 8: alias for data port */
    132 	ZSWR9_MASTER_IE | ZSWR9_NO_VECTOR,
    133 	0,	/*10: Misc. TX/RX control bits */
    134 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
    135 	((PCLK/32)/9600)-2,	/*12: BAUDLO (default=9600) */
    136 	0,			/*13: BAUDHI (default=9600) */
    137 	ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
    138 	ZSWR15_BREAK_IE,
    139 };
    140 
    141 /* Console ops */
    142 static int  zscngetc(dev_t);
    143 static void zscnputc(dev_t, int);
    144 static void zscnpollc(dev_t, int);
    145 
    146 struct consdev zs_consdev = {
    147 	.cn_getc = zscngetc,
    148 	.cn_putc = zscnputc,
    149 	.cn_pollc = zscnpollc,
    150 };
    151 
    152 
    153 /****************************************************************
    154  * Autoconfig
    155  ****************************************************************/
    156 
    157 /* Definition of the driver for autoconfig. */
    158 static int  zs_match_sbus(struct device *, struct cfdata *, void *);
    159 static void zs_attach_sbus(struct device *, struct device *, void *);
    160 
    161 static void zs_attach(struct zsc_softc *, struct zsdevice *, int);
    162 static int  zs_print(void *, const char *);
    163 
    164 CFATTACH_DECL(zs, sizeof(struct zsc_softc),
    165     zs_match_sbus, zs_attach_sbus, NULL, NULL);
    166 
    167 extern struct cfdriver zs_cd;
    168 
    169 /* Interrupt handlers. */
    170 int zscheckintr(void *);
    171 static int zshard(void *);
    172 static void zssoft(void *);
    173 
    174 static int zs_get_speed(struct zs_chanstate *);
    175 
    176 /* Console device support */
    177 static int zs_console_flags(int, int, int);
    178 
    179 /* Power management hooks */
    180 int  zs_enable(struct zs_chanstate *);
    181 void zs_disable(struct zs_chanstate *);
    182 
    183 /* from dev/ic/z8530tty.c */
    184 struct tty *zstty_get_tty_from_dev(struct device *);
    185 
    186 /*
    187  * Is the zs chip present?
    188  */
    189 static int
    190 zs_match_sbus(struct device *parent, struct cfdata *cf, void *aux)
    191 {
    192 	struct sbus_attach_args *sa = aux;
    193 
    194 	if (strcmp(cf->cf_name, sa->sa_name) != 0)
    195 		return (0);
    196 
    197 	return (1);
    198 }
    199 
    200 static void
    201 zs_attach_sbus(struct device *parent, struct device *self, void *aux)
    202 {
    203 	struct zsc_softc *zsc = (void *) self;
    204 	struct sbus_attach_args *sa = aux;
    205 	bus_space_handle_t bh;
    206 	int zs_unit = device_unit(&zsc->zsc_dev);
    207 
    208 	if (sa->sa_nintr == 0) {
    209 		printf(" no interrupt lines\n");
    210 		return;
    211 	}
    212 
    213 	/* Use the mapping setup by the Sun PROM if possible. */
    214 	if (zsaddr[zs_unit] == NULL) {
    215 		/* Only map registers once. */
    216 		if (sa->sa_npromvaddrs) {
    217 			/*
    218 			 * We're converting from a 32-bit pointer to a 64-bit
    219 			 * pointer.  Since the 32-bit entity is negative, but
    220 			 * the kernel is still mapped into the lower 4GB
    221 			 * range, this needs to be zero-extended.
    222 			 *
    223 			 * XXXXX If we map the kernel and devices into the
    224 			 * high 4GB range, this needs to be changed to
    225 			 * sign-extend the address.
    226 			 */
    227 			sparc_promaddr_to_handle(sa->sa_bustag,
    228 				sa->sa_promvaddrs[0], &bh);
    229 
    230 		} else {
    231 
    232 			if (sbus_bus_map(sa->sa_bustag, sa->sa_slot,
    233 					 sa->sa_offset,
    234 					 sa->sa_size,
    235 					 BUS_SPACE_MAP_LINEAR,
    236 					 &bh) != 0) {
    237 				printf("%s @ sbus: cannot map registers\n",
    238 				       self->dv_xname);
    239 				return;
    240 			}
    241 		}
    242 		zsaddr[zs_unit] = (struct zsdevice *)
    243 			bus_space_vaddr(sa->sa_bustag, bh);
    244 	}
    245 	zsc->zsc_bustag = sa->sa_bustag;
    246 	zsc->zsc_dmatag = sa->sa_dmatag;
    247 	zsc->zsc_promunit = prom_getpropint(sa->sa_node, "slave", -2);
    248 	zsc->zsc_node = sa->sa_node;
    249 	zs_attach(zsc, zsaddr[zs_unit], sa->sa_pri);
    250 }
    251 
    252 /*
    253  * Attach a found zs.
    254  *
    255  * USE ROM PROPERTIES port-a-ignore-cd AND port-b-ignore-cd FOR
    256  * SOFT CARRIER, AND keyboard PROPERTY FOR KEYBOARD/MOUSE?
    257  */
    258 static void
    259 zs_attach(struct zsc_softc *zsc, struct zsdevice *zsd, int pri)
    260 {
    261 	struct zsc_attach_args zsc_args;
    262 	struct zs_chanstate *cs;
    263 	int s, channel, softpri = PIL_TTY;
    264 
    265 	if (zsd == NULL) {
    266 		printf("configuration incomplete\n");
    267 		return;
    268 	}
    269 
    270 	printf(" softpri %d\n", softpri);
    271 
    272 	/*
    273 	 * Initialize software state for each channel.
    274 	 */
    275 	for (channel = 0; channel < 2; channel++) {
    276 		struct zschan *zc;
    277 		struct device *child;
    278 
    279 		zsc_args.channel = channel;
    280 		cs = &zsc->zsc_cs_store[channel];
    281 		zsc->zsc_cs[channel] = cs;
    282 
    283 		zs_lock_init(cs);
    284 		cs->cs_channel = channel;
    285 		cs->cs_private = NULL;
    286 		cs->cs_ops = &zsops_null;
    287 		cs->cs_brg_clk = PCLK / 16;
    288 
    289 		zc = (channel == 0) ? &zsd->zs_chan_a : &zsd->zs_chan_b;
    290 
    291 		zsc_args.consdev = NULL;
    292 		zsc_args.hwflags = zs_console_flags(zsc->zsc_promunit,
    293 						    zsc->zsc_node,
    294 						    channel);
    295 
    296 		if (zsc_args.hwflags & ZS_HWFLAG_CONSOLE) {
    297 			zsc_args.hwflags |= ZS_HWFLAG_USE_CONSDEV;
    298 			zsc_args.consdev = &zs_consdev;
    299 		}
    300 
    301 		if ((zsc_args.hwflags & ZS_HWFLAG_CONSOLE_INPUT) != 0) {
    302 			zs_conschan_get = zc;
    303 		}
    304 		if ((zsc_args.hwflags & ZS_HWFLAG_CONSOLE_OUTPUT) != 0) {
    305 			zs_conschan_put = zc;
    306 		}
    307 
    308 		/* Children need to set cn_dev, etc */
    309 		cs->cs_reg_csr  = &zc->zc_csr;
    310 		cs->cs_reg_data = &zc->zc_data;
    311 
    312 		memcpy(cs->cs_creg, zs_init_reg, 16);
    313 		memcpy(cs->cs_preg, zs_init_reg, 16);
    314 
    315 		/* XXX: Consult PROM properties for this?! */
    316 		cs->cs_defspeed = zs_get_speed(cs);
    317 		cs->cs_defcflag = zs_def_cflag;
    318 
    319 		/* Make these correspond to cs_defcflag (-crtscts) */
    320 		cs->cs_rr0_dcd = ZSRR0_DCD;
    321 		cs->cs_rr0_cts = 0;
    322 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
    323 		cs->cs_wr5_rts = 0;
    324 
    325 		/*
    326 		 * Clear the master interrupt enable.
    327 		 * The INTENA is common to both channels,
    328 		 * so just do it on the A channel.
    329 		 */
    330 		if (channel == 0) {
    331 			zs_write_reg(cs, 9, 0);
    332 		}
    333 
    334 		/*
    335 		 * Look for a child driver for this channel.
    336 		 * The child attach will setup the hardware.
    337 		 */
    338 		child = config_found(&zsc->zsc_dev, (void *)&zsc_args,
    339 		    zs_print);
    340 		if (child == NULL) {
    341 			/* No sub-driver.  Just reset it. */
    342 			u_char reset = (channel == 0) ?
    343 				ZSWR9_A_RESET : ZSWR9_B_RESET;
    344 			s = splzs();
    345 			zs_write_reg(cs,  9, reset);
    346 			splx(s);
    347 		}
    348 #if (NKBD > 0) || (NMS > 0)
    349 		/*
    350 		 * If this was a zstty it has a keyboard
    351 		 * property on it we need to attach the
    352 		 * sunkbd and sunms line disciplines.
    353 		 */
    354 		if (child
    355 		    && (device_is_a(child, "zstty"))
    356 		    && (prom_getproplen(zsc->zsc_node, "keyboard") == 0)) {
    357 			struct kbd_ms_tty_attach_args kma;
    358 			struct tty *tp;
    359 
    360 			kma.kmta_tp = tp = zstty_get_tty_from_dev(child);
    361 			kma.kmta_dev = tp->t_dev;
    362 			kma.kmta_consdev = zsc_args.consdev;
    363 
    364 			/* Attach 'em if we got 'em. */
    365 #if (NKBD > 0)
    366 			if (channel == 0) {
    367 				kma.kmta_name = "keyboard";
    368 				config_found(child, (void *)&kma, NULL);
    369 			}
    370 #endif
    371 #if (NMS > 0)
    372 			if (channel == 1) {
    373 				kma.kmta_name = "mouse";
    374 				config_found(child, (void *)&kma, NULL);
    375 			}
    376 #endif
    377 		}
    378 #endif
    379 	}
    380 
    381 	/*
    382 	 * Now safe to install interrupt handlers.  Note the arguments
    383 	 * to the interrupt handlers aren't used.  Note, we only do this
    384 	 * once since both SCCs interrupt at the same level and vector.
    385 	 */
    386 	bus_intr_establish(zsc->zsc_bustag, pri, IPL_SERIAL, zshard, zsc);
    387 	if (!(zsc->zsc_softintr = softintr_establish(softpri, zssoft, zsc)))
    388 		panic("zsattach: could not establish soft interrupt");
    389 
    390 	evcnt_attach_dynamic(&zsc->zsc_intrcnt, EVCNT_TYPE_INTR, NULL,
    391 	    zsc->zsc_dev.dv_xname, "intr");
    392 
    393 
    394 	/*
    395 	 * Set the master interrupt enable and interrupt vector.
    396 	 * (common to both channels, do it on A)
    397 	 */
    398 	cs = zsc->zsc_cs[0];
    399 	s = splhigh();
    400 	/* interrupt vector */
    401 	zs_write_reg(cs, 2, zs_init_reg[2]);
    402 	/* master interrupt control (enable) */
    403 	zs_write_reg(cs, 9, zs_init_reg[9]);
    404 	splx(s);
    405 
    406 }
    407 
    408 static int
    409 zs_print(void *aux, const char *name)
    410 {
    411 	struct zsc_attach_args *args = aux;
    412 
    413 	if (name != NULL)
    414 		aprint_normal("%s: ", name);
    415 
    416 	if (args->channel != -1)
    417 		aprint_normal(" channel %d", args->channel);
    418 
    419 	return (UNCONF);
    420 }
    421 
    422 /* Deprecate this? */
    423 static volatile int zssoftpending;
    424 
    425 static int
    426 zshard(void *arg)
    427 {
    428 	struct zsc_softc *zsc = (struct zsc_softc *)arg;
    429 	int rr3, rval;
    430 
    431 	rval = 0;
    432 	while ((rr3 = zsc_intr_hard(zsc))) {
    433 		/* Count up the interrupts. */
    434 		rval |= rr3;
    435 		zsc->zsc_intrcnt.ev_count++;
    436 	}
    437 	if (((zsc->zsc_cs[0] && zsc->zsc_cs[0]->cs_softreq) ||
    438 	     (zsc->zsc_cs[1] && zsc->zsc_cs[1]->cs_softreq)) &&
    439 	    zsc->zsc_softintr) {
    440 		zssoftpending = PIL_TTY;
    441 		softintr_schedule(zsc->zsc_softintr);
    442 	}
    443 	return (rval);
    444 }
    445 
    446 int
    447 zscheckintr(void *arg)
    448 {
    449 	struct zsc_softc *zsc;
    450 	int unit, rval;
    451 
    452 	rval = 0;
    453 	for (unit = 0; unit < zs_cd.cd_ndevs; unit++) {
    454 
    455 		zsc = zs_cd.cd_devs[unit];
    456 		if (zsc == NULL)
    457 			continue;
    458 		rval = (zshard((void *)zsc) || rval);
    459 	}
    460 	return (rval);
    461 }
    462 
    463 
    464 /*
    465  * We need this only for TTY_DEBUG purposes.
    466  */
    467 static void
    468 zssoft(void *arg)
    469 {
    470 	struct zsc_softc *zsc = (struct zsc_softc *)arg;
    471 	int s;
    472 
    473 	/* Make sure we call the tty layer at spltty. */
    474 	s = spltty();
    475 	zssoftpending = 0;
    476 	(void)zsc_intr_soft(zsc);
    477 #ifdef TTY_DEBUG
    478 	{
    479 		struct zstty_softc *zst0 = zsc->zsc_cs[0]->cs_private;
    480 		struct zstty_softc *zst1 = zsc->zsc_cs[1]->cs_private;
    481 		if (zst0->zst_overflows || zst1->zst_overflows ) {
    482 			struct trapframe *frame = (struct trapframe *)arg;
    483 
    484 			printf("zs silo overflow from %p\n",
    485 			       (long)frame->tf_pc);
    486 		}
    487 	}
    488 #endif
    489 	splx(s);
    490 }
    491 
    492 
    493 /*
    494  * Compute the current baud rate given a ZS channel.
    495  */
    496 static int
    497 zs_get_speed(struct zs_chanstate *cs)
    498 {
    499 	int tconst;
    500 
    501 	tconst = zs_read_reg(cs, 12);
    502 	tconst |= zs_read_reg(cs, 13) << 8;
    503 	return (TCONST_TO_BPS(cs->cs_brg_clk, tconst));
    504 }
    505 
    506 /*
    507  * MD functions for setting the baud rate and control modes.
    508  */
    509 int
    510 zs_set_speed(struct zs_chanstate *cs, int bps /* bits per second */)
    511 {
    512 	int tconst, real_bps;
    513 
    514 	if (bps == 0)
    515 		return (0);
    516 
    517 #ifdef	DIAGNOSTIC
    518 	if (cs->cs_brg_clk == 0)
    519 		panic("zs_set_speed");
    520 #endif
    521 
    522 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
    523 	if (tconst < 0)
    524 		return (EINVAL);
    525 
    526 	/* Convert back to make sure we can do it. */
    527 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
    528 
    529 	/* XXX - Allow some tolerance here? */
    530 	if (real_bps != bps)
    531 		return (EINVAL);
    532 
    533 	cs->cs_preg[12] = tconst;
    534 	cs->cs_preg[13] = tconst >> 8;
    535 
    536 	/* Caller will stuff the pending registers. */
    537 	return (0);
    538 }
    539 
    540 int
    541 zs_set_modes(struct zs_chanstate *cs, int cflag)
    542 {
    543 	int s;
    544 
    545 	/*
    546 	 * Output hardware flow control on the chip is horrendous:
    547 	 * if carrier detect drops, the receiver is disabled, and if
    548 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
    549 	 * Therefore, NEVER set the HFC bit, and instead use the
    550 	 * status interrupt to detect CTS changes.
    551 	 */
    552 	s = splzs();
    553 	cs->cs_rr0_pps = 0;
    554 	if ((cflag & (CLOCAL | MDMBUF)) != 0) {
    555 		cs->cs_rr0_dcd = 0;
    556 		if ((cflag & MDMBUF) == 0)
    557 			cs->cs_rr0_pps = ZSRR0_DCD;
    558 	} else
    559 		cs->cs_rr0_dcd = ZSRR0_DCD;
    560 	if ((cflag & CRTSCTS) != 0) {
    561 		cs->cs_wr5_dtr = ZSWR5_DTR;
    562 		cs->cs_wr5_rts = ZSWR5_RTS;
    563 		cs->cs_rr0_cts = ZSRR0_CTS;
    564 	} else if ((cflag & CDTRCTS) != 0) {
    565 		cs->cs_wr5_dtr = 0;
    566 		cs->cs_wr5_rts = ZSWR5_DTR;
    567 		cs->cs_rr0_cts = ZSRR0_CTS;
    568 	} else if ((cflag & MDMBUF) != 0) {
    569 		cs->cs_wr5_dtr = 0;
    570 		cs->cs_wr5_rts = ZSWR5_DTR;
    571 		cs->cs_rr0_cts = ZSRR0_DCD;
    572 	} else {
    573 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
    574 		cs->cs_wr5_rts = 0;
    575 		cs->cs_rr0_cts = 0;
    576 	}
    577 	splx(s);
    578 
    579 	/* Caller will stuff the pending registers. */
    580 	return (0);
    581 }
    582 
    583 
    584 /*
    585  * Read or write the chip with suitable delays.
    586  */
    587 
    588 u_char
    589 zs_read_reg(struct zs_chanstate *cs, u_char reg)
    590 {
    591 	u_char val;
    592 
    593 	*cs->cs_reg_csr = reg;
    594 	ZS_DELAY();
    595 	val = *cs->cs_reg_csr;
    596 	ZS_DELAY();
    597 	return (val);
    598 }
    599 
    600 void
    601 zs_write_reg(struct zs_chanstate *cs, u_char reg, u_char val)
    602 {
    603 	*cs->cs_reg_csr = reg;
    604 	ZS_DELAY();
    605 	*cs->cs_reg_csr = val;
    606 	ZS_DELAY();
    607 }
    608 
    609 u_char
    610 zs_read_csr(struct zs_chanstate *cs)
    611 {
    612 	u_char val;
    613 
    614 	val = *cs->cs_reg_csr;
    615 	ZS_DELAY();
    616 	return (val);
    617 }
    618 
    619 void
    620 zs_write_csr(struct zs_chanstate *cs, u_char val)
    621 {
    622 	*cs->cs_reg_csr = val;
    623 	ZS_DELAY();
    624 }
    625 
    626 u_char
    627 zs_read_data(struct zs_chanstate *cs)
    628 {
    629 	u_char val;
    630 
    631 	val = *cs->cs_reg_data;
    632 	ZS_DELAY();
    633 	return (val);
    634 }
    635 
    636 void
    637 zs_write_data(struct zs_chanstate *cs, u_char val)
    638 {
    639 	*cs->cs_reg_data = val;
    640 	ZS_DELAY();
    641 }
    642 
    643 /****************************************************************
    644  * Console support functions (Sun specific!)
    645  * Note: this code is allowed to know about the layout of
    646  * the chip registers, and uses that to keep things simple.
    647  * XXX - I think I like the mvme167 code better. -gwr
    648  ****************************************************************/
    649 
    650 extern void Debugger(void);
    651 
    652 /*
    653  * Handle user request to enter kernel debugger.
    654  */
    655 void
    656 zs_abort(struct zs_chanstate *cs)
    657 {
    658 	volatile struct zschan *zc = zs_conschan_get;
    659 	int rr0;
    660 
    661 	/* Wait for end of break to avoid PROM abort. */
    662 	/* XXX - Limit the wait? */
    663 	do {
    664 		rr0 = zc->zc_csr;
    665 		ZS_DELAY();
    666 	} while (rr0 & ZSRR0_BREAK);
    667 
    668 #if defined(KGDB)
    669 	zskgdb(cs);
    670 #elif defined(DDB)
    671 	{
    672 		extern int db_active;
    673 
    674 		if (!db_active)
    675 			Debugger();
    676 		else
    677 			/* Debugger is probably hozed */
    678 			callrom();
    679 	}
    680 #else
    681 	printf("stopping on keyboard abort\n");
    682 	callrom();
    683 #endif
    684 }
    685 
    686 
    687 /*
    688  * Polled input char.
    689  */
    690 int
    691 zs_getc(void *arg)
    692 {
    693 	volatile struct zschan *zc = arg;
    694 	int s, c, rr0;
    695 
    696 	s = splhigh();
    697 	/* Wait for a character to arrive. */
    698 	do {
    699 		rr0 = zc->zc_csr;
    700 		ZS_DELAY();
    701 	} while ((rr0 & ZSRR0_RX_READY) == 0);
    702 
    703 	c = zc->zc_data;
    704 	ZS_DELAY();
    705 	splx(s);
    706 
    707 	/*
    708 	 * This is used by the kd driver to read scan codes,
    709 	 * so don't translate '\r' ==> '\n' here...
    710 	 */
    711 	return (c);
    712 }
    713 
    714 /*
    715  * Polled output char.
    716  */
    717 void
    718 zs_putc(void *arg, int c)
    719 {
    720 	volatile struct zschan *zc = arg;
    721 	int s, rr0;
    722 
    723 	s = splhigh();
    724 
    725 	/* Wait for transmitter to become ready. */
    726 	do {
    727 		rr0 = zc->zc_csr;
    728 		ZS_DELAY();
    729 	} while ((rr0 & ZSRR0_TX_READY) == 0);
    730 
    731 	/*
    732 	 * Send the next character.
    733 	 * Now you'd think that this could be followed by a ZS_DELAY()
    734 	 * just like all the other chip accesses, but it turns out that
    735 	 * the `transmit-ready' interrupt isn't de-asserted until
    736 	 * some period of time after the register write completes
    737 	 * (more than a couple instructions).  So to avoid stray
    738 	 * interrupts we put in the 2us delay regardless of CPU model.
    739 	 */
    740 	zc->zc_data = c;
    741 	delay(2);
    742 
    743 	splx(s);
    744 }
    745 
    746 /*****************************************************************/
    747 
    748 
    749 
    750 
    751 /*
    752  * Polled console input putchar.
    753  */
    754 static int
    755 zscngetc(dev_t dev)
    756 {
    757 	return (zs_getc(zs_conschan_get));
    758 }
    759 
    760 /*
    761  * Polled console output putchar.
    762  */
    763 static void
    764 zscnputc(dev_t dev, int c)
    765 {
    766 	zs_putc(zs_conschan_put, c);
    767 }
    768 
    769 int swallow_zsintrs;
    770 
    771 static void
    772 zscnpollc(dev_t dev, int on)
    773 {
    774 	/*
    775 	 * Need to tell zs driver to acknowledge all interrupts or we get
    776 	 * annoying spurious interrupt messages.  This is because mucking
    777 	 * with spl() levels during polling does not prevent interrupts from
    778 	 * being generated.
    779 	 */
    780 
    781 	if (on) swallow_zsintrs++;
    782 	else swallow_zsintrs--;
    783 }
    784 
    785 int
    786 zs_console_flags(int promunit, int node, int channel)
    787 {
    788 	int cookie, flags = 0;
    789 	char buf[255];
    790 
    791 	/*
    792 	 * We'll just do the OBP grovelling down here since that's
    793 	 * the only type of firmware we support.
    794 	 */
    795 
    796 	/* Default to channel 0 if there are no explicit prom args */
    797 	cookie = 0;
    798 	if (node == prom_instance_to_package(prom_stdin())) {
    799 		if (prom_getoption("input-device", buf, sizeof buf) == 0 &&
    800 		    strcmp("ttyb", buf) == 0)
    801 			cookie = 1;
    802 
    803 		if (channel == cookie)
    804 			flags |= ZS_HWFLAG_CONSOLE_INPUT;
    805 	}
    806 
    807 	if (node == prom_instance_to_package(prom_stdout())) {
    808 		if (prom_getoption("output-device", buf, sizeof buf) == 0 &&
    809 		    strcmp("ttyb", buf) == 0)
    810 			cookie = 1;
    811 
    812 		if (channel == cookie)
    813 			flags |= ZS_HWFLAG_CONSOLE_OUTPUT;
    814 	}
    815 
    816 	return (flags);
    817 }
    818 
    819