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zs_ioasic.c revision 1.12
      1 /* $NetBSD: zs_ioasic.c,v 1.12 2002/09/24 13:23:32 ad Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 1996, 1998 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, Ken Hornstein, and by Jason R. Thorpe of the
      9  * Numerical Aerospace Simulation Facility, NASA Ames Research Center.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions and the following disclaimer.
     16  * 2. Redistributions in binary form must reproduce the above copyright
     17  *    notice, this list of conditions and the following disclaimer in the
     18  *    documentation and/or other materials provided with the distribution.
     19  * 3. All advertising materials mentioning features or use of this software
     20  *    must display the following acknowledgement:
     21  *        This product includes software developed by the NetBSD
     22  *        Foundation, Inc. and its contributors.
     23  * 4. Neither the name of The NetBSD Foundation nor the names of its
     24  *    contributors may be used to endorse or promote products derived
     25  *    from this software without specific prior written permission.
     26  *
     27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     37  * POSSIBILITY OF SUCH DAMAGE.
     38  */
     39 
     40 /*
     41  * Zilog Z8530 Dual UART driver (machine-dependent part).  This driver
     42  * handles Z8530 chips attached to the DECstation/Alpha IOASIC.  Modified
     43  * for NetBSD/alpha by Ken Hornstein and Jason R. Thorpe.  NetBSD/pmax
     44  * adaption by Mattias Drochner.  Merge work by Tohru Nishimura.
     45  *
     46  * Runs two serial lines per chip using slave drivers.
     47  * Plain tty/async lines use the zstty slave.
     48  */
     49 
     50 #include <sys/cdefs.h>
     51 __KERNEL_RCSID(0, "$NetBSD: zs_ioasic.c,v 1.12 2002/09/24 13:23:32 ad Exp $");
     52 
     53 #include "opt_ddb.h"
     54 #include "opt_kgdb.h"
     55 #include "zskbd.h"
     56 
     57 #include <sys/param.h>
     58 #include <sys/systm.h>
     59 #include <sys/conf.h>
     60 #include <sys/device.h>
     61 #include <sys/malloc.h>
     62 #include <sys/file.h>
     63 #include <sys/ioctl.h>
     64 #include <sys/kernel.h>
     65 #include <sys/proc.h>
     66 #include <sys/tty.h>
     67 #include <sys/time.h>
     68 #include <sys/syslog.h>
     69 
     70 #include <machine/autoconf.h>
     71 #include <machine/intr.h>
     72 #include <machine/z8530var.h>
     73 
     74 #include <dev/cons.h>
     75 #include <dev/ic/z8530reg.h>
     76 
     77 #include <dev/tc/tcvar.h>
     78 #include <dev/tc/ioasicreg.h>
     79 #include <dev/tc/ioasicvar.h>
     80 
     81 #include <dev/tc/zs_ioasicvar.h>
     82 
     83 #if defined(__alpha__) || defined(alpha)
     84 #include <machine/rpb.h>
     85 #endif
     86 #if defined(pmax)
     87 #include <pmax/pmax/pmaxtype.h>
     88 #endif
     89 
     90 /*
     91  * Helpers for console support.
     92  */
     93 void	zs_ioasic_cninit __P((tc_addr_t, tc_offset_t, int));
     94 int	zs_ioasic_cngetc __P((dev_t));
     95 void	zs_ioasic_cnputc __P((dev_t, int));
     96 void	zs_ioasic_cnpollc __P((dev_t, int));
     97 
     98 struct consdev zs_ioasic_cons = {
     99 	NULL, NULL, zs_ioasic_cngetc, zs_ioasic_cnputc,
    100 	zs_ioasic_cnpollc, NULL, NODEV, CN_NORMAL,
    101 };
    102 
    103 tc_offset_t zs_ioasic_console_offset;
    104 int zs_ioasic_console_channel;
    105 int zs_ioasic_console;
    106 struct zs_chanstate zs_ioasic_conschanstate_store;
    107 
    108 int	zs_ioasic_isconsole __P((tc_offset_t, int));
    109 int	zs_getc __P((struct zs_chanstate *));
    110 void	zs_putc __P((struct zs_chanstate *, int));
    111 
    112 /*
    113  * Some warts needed by z8530tty.c
    114  */
    115 int zs_def_cflag = (TTYDEF_CFLAG & ~(CSIZE | PARENB)) | CS8;
    116 
    117 /*
    118  * ZS chips are feeded a 7.372 MHz clock.
    119  */
    120 #define	PCLK	(9600 * 768)	/* PCLK pin input clock rate */
    121 
    122 /* The layout of this is hardware-dependent (padding, order). */
    123 struct zshan {
    124 #if defined(__alpha__) || defined(alpha)
    125 	volatile u_int	zc_csr;		/* ctrl,status, and indirect access */
    126 	u_int		zc_pad0;
    127 	volatile u_int	zc_data;	/* data */
    128 	u_int		sc_pad1;
    129 #endif
    130 #if defined(pmax)
    131 	volatile u_int16_t zc_csr;	/* ctrl,status, and indirect access */
    132 	unsigned : 16;
    133 	volatile u_int16_t zc_data;	/* data */
    134 	unsigned : 16;
    135 #endif
    136 };
    137 
    138 struct zsdevice {
    139 	/* Yes, they are backwards. */
    140 	struct	zshan zs_chan_b;
    141 	struct	zshan zs_chan_a;
    142 };
    143 
    144 static u_char zs_ioasic_init_reg[16] = {
    145 	0,	/* 0: CMD (reset, etc.) */
    146 	0,	/* 1: No interrupts yet. */
    147 	0xf0,	/* 2: IVECT */
    148 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
    149 	ZSWR4_CLK_X16 | ZSWR4_ONESB,
    150 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
    151 	0,	/* 6: TXSYNC/SYNCLO */
    152 	0,	/* 7: RXSYNC/SYNCHI */
    153 	0,	/* 8: alias for data port */
    154 	ZSWR9_MASTER_IE | ZSWR9_VECTOR_INCL_STAT,
    155 	0,	/*10: Misc. TX/RX control bits */
    156 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
    157 	22,	/*12: BAUDLO (default=9600) */
    158 	0,	/*13: BAUDHI (default=9600) */
    159 	ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
    160 	ZSWR15_BREAK_IE,
    161 };
    162 
    163 struct zshan *zs_ioasic_get_chan_addr __P((tc_addr_t, int));
    164 
    165 struct zshan *
    166 zs_ioasic_get_chan_addr(zsaddr, channel)
    167 	tc_addr_t zsaddr;
    168 	int channel;
    169 {
    170 	struct zsdevice *addr;
    171 	struct zshan *zc;
    172 
    173 #if defined(__alpha__) || defined(alpha)
    174 	addr = (struct zsdevice *)TC_DENSE_TO_SPARSE(zsaddr);
    175 #endif
    176 #if defined(pmax)
    177 	addr = (struct zsdevice *)MIPS_PHYS_TO_KSEG1(zsaddr);
    178 #endif
    179 
    180 	if (channel == 0)
    181 		zc = &addr->zs_chan_a;
    182 	else
    183 		zc = &addr->zs_chan_b;
    184 
    185 	return (zc);
    186 }
    187 
    188 
    189 /****************************************************************
    190  * Autoconfig
    191  ****************************************************************/
    192 
    193 /* Definition of the driver for autoconfig. */
    194 int	zs_ioasic_match __P((struct device *, struct cfdata *, void *));
    195 void	zs_ioasic_attach __P((struct device *, struct device *, void *));
    196 int	zs_ioasic_print __P((void *, const char *name));
    197 int	zs_ioasic_submatch __P((struct device *, struct cfdata *, void *));
    198 
    199 struct cfattach zsc_ioasic_ca = {
    200 	sizeof(struct zsc_softc), zs_ioasic_match, zs_ioasic_attach
    201 };
    202 
    203 /* Interrupt handlers. */
    204 int	zs_ioasic_hardintr __P((void *));
    205 void	zs_ioasic_softintr __P((void *));
    206 
    207 extern struct cfdriver ioasic_cd;
    208 
    209 /*
    210  * Is the zs chip present?
    211  */
    212 int
    213 zs_ioasic_match(parent, cf, aux)
    214 	struct device *parent;
    215 	struct cfdata *cf;
    216 	void *aux;
    217 {
    218 	struct ioasicdev_attach_args *d = aux;
    219 	tc_addr_t zs_addr;
    220 
    221 	if (parent->dv_cfdata->cf_driver != &ioasic_cd)
    222 		return (0);
    223 
    224 	/*
    225 	 * Make sure that we're looking for the right kind of device.
    226 	 */
    227 	if (strncmp(d->iada_modname, "z8530   ", TC_ROM_LLEN) != 0 &&
    228 	    strncmp(d->iada_modname, "scc", TC_ROM_LLEN) != 0)
    229 		return (0);
    230 
    231 	/*
    232 	 * Check user-specified offset against the ioasic offset.
    233 	 * Allow it to be wildcarded.
    234 	 */
    235 	if (cf->cf_loc[IOASICCF_OFFSET] != IOASICCF_OFFSET_DEFAULT &&
    236 	    cf->cf_loc[IOASICCF_OFFSET] != d->iada_offset)
    237 		return (0);
    238 
    239 	/*
    240 	 * Find out the device address, and check it for validity.
    241 	 */
    242 	zs_addr = TC_DENSE_TO_SPARSE((tc_addr_t)d->iada_addr);
    243 	if (tc_badaddr(zs_addr))
    244 		return (0);
    245 
    246 	return (1);
    247 }
    248 
    249 /*
    250  * Attach a found zs.
    251  */
    252 void
    253 zs_ioasic_attach(parent, self, aux)
    254 	struct device *parent;
    255 	struct device *self;
    256 	void *aux;
    257 {
    258 	struct zsc_softc *zs = (void *) self;
    259 	struct zsc_attach_args zs_args;
    260 	struct zs_chanstate *cs;
    261 	struct ioasicdev_attach_args *d = aux;
    262 	struct zshan *zc;
    263 	int s, channel;
    264 	u_long zflg;
    265 
    266 	printf("\n");
    267 
    268 	/*
    269 	 * Initialize software state for each channel.
    270 	 */
    271 	for (channel = 0; channel < 2; channel++) {
    272 		zs_args.channel = channel;
    273 		zs_args.hwflags = 0;
    274 
    275 		if (zs_ioasic_isconsole(d->iada_offset, channel)) {
    276 			cs = &zs_ioasic_conschanstate_store;
    277 			zs_args.hwflags |= ZS_HWFLAG_CONSOLE;
    278 		} else {
    279 			cs = malloc(sizeof(struct zs_chanstate),
    280 					M_DEVBUF, M_NOWAIT|M_ZERO);
    281 			zc = zs_ioasic_get_chan_addr(d->iada_addr, channel);
    282 			cs->cs_reg_csr = (void *)&zc->zc_csr;
    283 
    284 			bcopy(zs_ioasic_init_reg, cs->cs_creg, 16);
    285 			bcopy(zs_ioasic_init_reg, cs->cs_preg, 16);
    286 
    287 			cs->cs_defcflag = zs_def_cflag;
    288 			cs->cs_defspeed = 9600;		/* XXX */
    289 			(void) zs_set_modes(cs, cs->cs_defcflag);
    290 		}
    291 
    292 		zs->zsc_cs[channel] = cs;
    293 		zs->zsc_addroffset = d->iada_offset; /* cookie only */
    294 		cs->cs_channel = channel;
    295 		cs->cs_ops = &zsops_null;
    296 		cs->cs_brg_clk = PCLK / 16;
    297 
    298 		/*
    299 		 * DCD and CTS interrupts are only meaningful on
    300 		 * SCC 0/B, and RTS and DTR only on B of SCC 0 & 1.
    301 		 *
    302 		 * XXX This is sorta gross.
    303 		 */
    304 		if (d->iada_offset == 0x00100000 && channel == 1) {
    305 			cs->cs_creg[15] |= ZSWR15_DCD_IE;
    306 			cs->cs_preg[15] |= ZSWR15_DCD_IE;
    307 			zflg = ZIP_FLAGS_DCDCTS;
    308 		} else
    309 			zflg = 0;
    310 		if (channel == 1)
    311 			zflg |= ZIP_FLAGS_DTRRTS;
    312 		(u_long)cs->cs_private = zflg;
    313 
    314 		/*
    315 		 * Clear the master interrupt enable.
    316 		 * The INTENA is common to both channels,
    317 		 * so just do it on the A channel.
    318 		 */
    319 		if (channel == 0) {
    320 			zs_write_reg(cs, 9, 0);
    321 		}
    322 
    323 		/*
    324 		 * Set up the flow/modem control channel pointer to
    325 		 * deal with the weird wiring on the TC Alpha and
    326 		 * DECstation.
    327 		 */
    328 		if (channel == 1)
    329 			cs->cs_ctl_chan = zs->zsc_cs[0];
    330 		else
    331 			cs->cs_ctl_chan = NULL;
    332 
    333 		/*
    334 		 * Look for a child driver for this channel.
    335 		 * The child attach will setup the hardware.
    336 		 */
    337 		if (config_found_sm(self, (void *)&zs_args,
    338 				zs_ioasic_print, zs_ioasic_submatch) == NULL) {
    339 			/* No sub-driver.  Just reset it. */
    340 			u_char reset = (channel == 0) ?
    341 				ZSWR9_A_RESET : ZSWR9_B_RESET;
    342 			s = splhigh();
    343 			zs_write_reg(cs, 9, reset);
    344 			splx(s);
    345 		}
    346 	}
    347 
    348 	/*
    349 	 * Set up the ioasic interrupt handler.
    350 	 */
    351 	ioasic_intr_establish(parent, d->iada_cookie, TC_IPL_TTY,
    352 	    zs_ioasic_hardintr, zs);
    353 	zs->zsc_sih = softintr_establish(IPL_SOFTSERIAL,
    354 	    zs_ioasic_softintr, zs);
    355 	if (zs->zsc_sih == NULL)
    356 		panic("zs_ioasic_attach: unable to register softintr");
    357 
    358 	/*
    359 	 * Set the master interrupt enable and interrupt vector.  The
    360 	 * Sun does this only on one channel.  The old Alpha SCC driver
    361 	 * did it on both.  We'll do it on both.
    362 	 */
    363 	s = splhigh();
    364 	/* interrupt vector */
    365 	zs_write_reg(zs->zsc_cs[0], 2, zs_ioasic_init_reg[2]);
    366 	zs_write_reg(zs->zsc_cs[1], 2, zs_ioasic_init_reg[2]);
    367 
    368 	/* master interrupt control (enable) */
    369 	zs_write_reg(zs->zsc_cs[0], 9, zs_ioasic_init_reg[9]);
    370 	zs_write_reg(zs->zsc_cs[1], 9, zs_ioasic_init_reg[9]);
    371 #if defined(__alpha__) || defined(alpha)
    372 	/* ioasic interrupt enable */
    373 	*(volatile u_int *)(ioasic_base + IOASIC_IMSK) |=
    374 		    IOASIC_INTR_SCC_1 | IOASIC_INTR_SCC_0;
    375 	tc_mb();
    376 #endif
    377 	splx(s);
    378 }
    379 
    380 int
    381 zs_ioasic_print(aux, name)
    382 	void *aux;
    383 	const char *name;
    384 {
    385 	struct zsc_attach_args *args = aux;
    386 
    387 	if (name != NULL)
    388 		printf("%s:", name);
    389 
    390 	if (args->channel != -1)
    391 		printf(" channel %d", args->channel);
    392 
    393 	return (UNCONF);
    394 }
    395 
    396 int
    397 zs_ioasic_submatch(parent, cf, aux)
    398 	struct device *parent;
    399 	struct cfdata *cf;
    400 	void *aux;
    401 {
    402 	struct zsc_softc *zs = (void *)parent;
    403 	struct zsc_attach_args *pa = aux;
    404 	char *defname = "";
    405 
    406 	if (cf->cf_loc[ZSCCF_CHANNEL] != ZSCCF_CHANNEL_DEFAULT &&
    407 	    cf->cf_loc[ZSCCF_CHANNEL] != pa->channel)
    408 		return (0);
    409 	if (cf->cf_loc[ZSCCF_CHANNEL] == ZSCCF_CHANNEL_DEFAULT) {
    410 		if (pa->channel == 0) {
    411 #if defined(pmax)
    412 			if (systype == DS_MAXINE)
    413 				return (0);
    414 #endif
    415 			if (zs->zsc_addroffset == 0x100000)
    416 				defname = "vsms";
    417 			else
    418 				defname = "lkkbd";
    419 		}
    420 		else if (zs->zsc_addroffset == 0x100000)
    421 			defname = "zstty";
    422 #if defined(pmax)
    423 		else if (systype == DS_MAXINE)
    424 			return (0);
    425 #endif
    426 #if defined(__alpha__) || defined(alpha)
    427 		else if (cputype == ST_DEC_3000_300)
    428 			return (0);
    429 #endif
    430 		else
    431 			defname = "zstty"; /* 3min/3max+, DEC3000/500 */
    432 
    433 		if (strcmp(cf->cf_driver->cd_name, defname))
    434 			return (0);
    435 	}
    436 	return ((*cf->cf_attach->ca_match)(parent, cf, aux));
    437 }
    438 
    439 /*
    440  * Hardware interrupt handler.
    441  */
    442 int
    443 zs_ioasic_hardintr(arg)
    444 	void *arg;
    445 {
    446 	struct zsc_softc *zsc = arg;
    447 
    448 	/*
    449 	 * Call the upper-level MI hardware interrupt handler.
    450 	 */
    451 	zsc_intr_hard(zsc);
    452 
    453 	/*
    454 	 * Check to see if we need to schedule any software-level
    455 	 * processing interrupts.
    456 	 */
    457 	if (zsc->zsc_cs[0]->cs_softreq | zsc->zsc_cs[1]->cs_softreq)
    458 		softintr_schedule(zsc->zsc_sih);
    459 
    460 	return (1);
    461 }
    462 
    463 /*
    464  * Software-level interrupt (character processing, lower priority).
    465  */
    466 void
    467 zs_ioasic_softintr(arg)
    468 	void *arg;
    469 {
    470 	struct zsc_softc *zsc = arg;
    471 	int s;
    472 
    473 	s = spltty();
    474 	(void) zsc_intr_soft(zsc);
    475 	splx(s);
    476 }
    477 
    478 /*
    479  * MD functions for setting the baud rate and control modes.
    480  */
    481 int
    482 zs_set_speed(cs, bps)
    483 	struct zs_chanstate *cs;
    484 	int bps;	/* bits per second */
    485 {
    486 	int tconst, real_bps;
    487 
    488 	if (bps == 0)
    489 		return (0);
    490 
    491 #ifdef DIAGNOSTIC
    492 	if (cs->cs_brg_clk == 0)
    493 		panic("zs_set_speed");
    494 #endif
    495 
    496 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
    497 	if (tconst < 0)
    498 		return (EINVAL);
    499 
    500 	/* Convert back to make sure we can do it. */
    501 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
    502 
    503 	/* XXX - Allow some tolerance here? */
    504 	if (real_bps != bps)
    505 		return (EINVAL);
    506 
    507 	cs->cs_preg[12] = tconst;
    508 	cs->cs_preg[13] = tconst >> 8;
    509 
    510 	/* Caller will stuff the pending registers. */
    511 	return (0);
    512 }
    513 
    514 int
    515 zs_set_modes(cs, cflag)
    516 	struct zs_chanstate *cs;
    517 	int cflag;	/* bits per second */
    518 {
    519 	u_long privflags = (u_long)cs->cs_private;
    520 	int s;
    521 
    522 	/*
    523 	 * Output hardware flow control on the chip is horrendous:
    524 	 * if carrier detect drops, the receiver is disabled, and if
    525 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
    526 	 * Therefore, NEVER set the HFC bit, and instead use the
    527 	 * status interrupt to detect CTS changes.
    528 	 */
    529 	s = splzs();
    530 	if ((cflag & (CLOCAL | MDMBUF)) != 0)
    531 		cs->cs_rr0_dcd = 0;
    532 	else
    533 		cs->cs_rr0_dcd = ZSRR0_DCD;
    534 	if ((cflag & CRTSCTS) != 0) {
    535 		cs->cs_wr5_dtr = ZSWR5_DTR;
    536 		cs->cs_wr5_rts = ZSWR5_RTS;
    537 		cs->cs_rr0_cts = ZSRR0_CTS;
    538 	} else if ((cflag & CDTRCTS) != 0) {
    539 		cs->cs_wr5_dtr = 0;
    540 		cs->cs_wr5_rts = ZSWR5_DTR;
    541 		cs->cs_rr0_cts = ZSRR0_CTS;
    542 	} else if ((cflag & MDMBUF) != 0) {
    543 		cs->cs_wr5_dtr = 0;
    544 		cs->cs_wr5_rts = ZSWR5_DTR;
    545 		cs->cs_rr0_cts = ZSRR0_DCD;
    546 	} else {
    547 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
    548 		cs->cs_wr5_rts = 0;
    549 		cs->cs_rr0_cts = 0;
    550 	}
    551 
    552 	if ((privflags & ZIP_FLAGS_DCDCTS) == 0) {
    553 		cs->cs_rr0_dcd &= ~(ZSRR0_CTS|ZSRR0_DCD);
    554 		cs->cs_rr0_cts &= ~(ZSRR0_CTS|ZSRR0_DCD);
    555 	}
    556 	if ((privflags & ZIP_FLAGS_DTRRTS) == 0) {
    557 		cs->cs_wr5_dtr &= ~(ZSWR5_RTS|ZSWR5_DTR);
    558 		cs->cs_wr5_rts &= ~(ZSWR5_RTS|ZSWR5_DTR);
    559 	}
    560 	splx(s);
    561 
    562 	/* Caller will stuff the pending registers. */
    563 	return (0);
    564 }
    565 
    566 /*
    567  * Functions to read and write individual registers in a channel.
    568  * The ZS chip requires a 1.6 uSec. recovery time between accesses,
    569  * and the Alpha TC hardware does NOT take care of this for you.
    570  * The delay is now handled inside the chip access functions.
    571  * These could be inlines, but with the delay, speed is moot.
    572  */
    573 #if defined(pmax)
    574 #undef	DELAY
    575 #define	DELAY(x)
    576 #endif
    577 
    578 u_int
    579 zs_read_reg(cs, reg)
    580 	struct zs_chanstate *cs;
    581 	u_int reg;
    582 {
    583 	struct zshan *zc = (void *)cs->cs_reg_csr;
    584 	unsigned val;
    585 
    586 	zc->zc_csr = reg << 8;
    587 	tc_wmb();
    588 	DELAY(5);
    589 	val = (zc->zc_csr >> 8) & 0xff;
    590 	/* tc_mb(); */
    591 	DELAY(5);
    592 	return (val);
    593 }
    594 
    595 void
    596 zs_write_reg(cs, reg, val)
    597 	struct zs_chanstate *cs;
    598 	u_int reg, val;
    599 {
    600 	struct zshan *zc = (void *)cs->cs_reg_csr;
    601 
    602 	zc->zc_csr = reg << 8;
    603 	tc_wmb();
    604 	DELAY(5);
    605 	zc->zc_csr = val << 8;
    606 	tc_wmb();
    607 	DELAY(5);
    608 }
    609 
    610 u_int
    611 zs_read_csr(cs)
    612 	struct zs_chanstate *cs;
    613 {
    614 	struct zshan *zc = (void *)cs->cs_reg_csr;
    615 	unsigned val;
    616 
    617 	val = (zc->zc_csr >> 8) & 0xff;
    618 	/* tc_mb(); */
    619 	DELAY(5);
    620 	return (val);
    621 }
    622 
    623 void
    624 zs_write_csr(cs, val)
    625 	struct zs_chanstate *cs;
    626 	u_int val;
    627 {
    628 	struct zshan *zc = (void *)cs->cs_reg_csr;
    629 
    630 	zc->zc_csr = val << 8;
    631 	tc_wmb();
    632 	DELAY(5);
    633 }
    634 
    635 u_int
    636 zs_read_data(cs)
    637 	struct zs_chanstate *cs;
    638 {
    639 	struct zshan *zc = (void *)cs->cs_reg_csr;
    640 	unsigned val;
    641 
    642 	val = (zc->zc_data) >> 8 & 0xff;
    643 	/* tc_mb(); */
    644 	DELAY(5);
    645 	return (val);
    646 }
    647 
    648 void
    649 zs_write_data(cs, val)
    650 	struct zs_chanstate *cs;
    651 	u_int val;
    652 {
    653 	struct zshan *zc = (void *)cs->cs_reg_csr;
    654 
    655 	zc->zc_data = val << 8;
    656 	tc_wmb();
    657 	DELAY(5);
    658 }
    659 
    660 /****************************************************************
    661  * Console support functions
    662  ****************************************************************/
    663 
    664 /*
    665  * Handle user request to enter kernel debugger.
    666  */
    667 void
    668 zs_abort(cs)
    669 	struct zs_chanstate *cs;
    670 {
    671 	int rr0;
    672 
    673 	/* Wait for end of break. */
    674 	/* XXX - Limit the wait? */
    675 	do {
    676 		rr0 = zs_read_csr(cs);
    677 	} while (rr0 & ZSRR0_BREAK);
    678 
    679 #if defined(KGDB)
    680 	zskgdb(cs);
    681 #elif defined(DDB)
    682 	Debugger();
    683 #else
    684 	printf("zs_abort: ignoring break on console\n");
    685 #endif
    686 }
    687 
    688 /*
    689  * Polled input char.
    690  */
    691 int
    692 zs_getc(cs)
    693 	struct zs_chanstate *cs;
    694 {
    695 	int s, c, rr0;
    696 
    697 	s = splhigh();
    698 	/* Wait for a character to arrive. */
    699 	do {
    700 		rr0 = zs_read_csr(cs);
    701 	} while ((rr0 & ZSRR0_RX_READY) == 0);
    702 
    703 	c = zs_read_data(cs);
    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(cs, c)
    718 	struct zs_chanstate *cs;
    719 	int c;
    720 {
    721 	register int s, rr0;
    722 
    723 	s = splhigh();
    724 	/* Wait for transmitter to become ready. */
    725 	do {
    726 		rr0 = zs_read_csr(cs);
    727 	} while ((rr0 & ZSRR0_TX_READY) == 0);
    728 
    729 	zs_write_data(cs, c);
    730 
    731 	/* Wait for the character to be transmitted. */
    732 	do {
    733 		rr0 = zs_read_csr(cs);
    734 	} while ((rr0 & ZSRR0_TX_READY) == 0);
    735 	splx(s);
    736 }
    737 
    738 /*****************************************************************/
    739 
    740 /*
    741  * zs_ioasic_cninit --
    742  *	Initialize the serial channel for either a keyboard or
    743  *	a serial console.
    744  */
    745 void
    746 zs_ioasic_cninit(ioasic_addr, zs_offset, channel)
    747 	tc_addr_t ioasic_addr;
    748 	tc_offset_t zs_offset;
    749 	int channel;
    750 {
    751 	struct zs_chanstate *cs;
    752 	tc_addr_t zs_addr;
    753 	struct zshan *zc;
    754 	u_long zflg;
    755 
    756 	/*
    757 	 * Initialize the console finder helpers.
    758 	 */
    759 	zs_ioasic_console_offset = zs_offset;
    760 	zs_ioasic_console_channel = channel;
    761 	zs_ioasic_console = 1;
    762 
    763 	/*
    764 	 * Pointer to channel state.
    765 	 */
    766 	cs = &zs_ioasic_conschanstate_store;
    767 
    768 	/*
    769 	 * Compute the physical address of the chip, "map" it via
    770 	 * K0SEG, and then get the address of the actual channel.
    771 	 */
    772 #if defined(__alpha__) || defined(alpha)
    773 	zs_addr = ALPHA_PHYS_TO_K0SEG(ioasic_addr + zs_offset);
    774 #endif
    775 #if defined(pmax)
    776 	zs_addr = MIPS_PHYS_TO_KSEG1(ioasic_addr + zs_offset);
    777 #endif
    778 	zc = zs_ioasic_get_chan_addr(zs_addr, channel);
    779 
    780 	/* Setup temporary chanstate. */
    781 	cs->cs_reg_csr = (void *)&zc->zc_csr;
    782 
    783 	cs->cs_channel = channel;
    784 	cs->cs_ops = &zsops_null;
    785 	cs->cs_brg_clk = PCLK / 16;
    786 
    787 	/* Initialize the pending registers. */
    788 	bcopy(zs_ioasic_init_reg, cs->cs_preg, 16);
    789 	/* cs->cs_preg[5] |= (ZSWR5_DTR | ZSWR5_RTS); */
    790 
    791 	/*
    792 	 * DCD and CTS interrupts are only meaningful on
    793 	 * SCC 0/B, and RTS and DTR only on B of SCC 0 & 1.
    794 	 *
    795 	 * XXX This is sorta gross.
    796 	 */
    797 	if (zs_offset == 0x00100000 && channel == 1)
    798 		zflg = ZIP_FLAGS_DCDCTS;
    799 	else
    800 		zflg = 0;
    801 	if (channel == 1)
    802 		zflg |= ZIP_FLAGS_DTRRTS;
    803 	(u_long)cs->cs_private = zflg;
    804 
    805 	/* Clear the master interrupt enable. */
    806 	zs_write_reg(cs, 9, 0);
    807 
    808 	/* Reset the whole SCC chip. */
    809 	zs_write_reg(cs, 9, ZSWR9_HARD_RESET);
    810 
    811 	/* Copy "pending" to "current" and H/W. */
    812 	zs_loadchannelregs(cs);
    813 }
    814 
    815 /*
    816  * zs_ioasic_cnattach --
    817  *	Initialize and attach a serial console.
    818  */
    819 void
    820 zs_ioasic_cnattach(ioasic_addr, zs_offset, channel)
    821 	tc_addr_t ioasic_addr;
    822 	tc_offset_t zs_offset;
    823 	int channel;
    824 {
    825 	struct zs_chanstate *cs = &zs_ioasic_conschanstate_store;
    826 	extern const struct cdevsw zstty_cdevsw;
    827 
    828 	zs_ioasic_cninit(ioasic_addr, zs_offset, channel);
    829 	cs->cs_defspeed = 9600;
    830 	cs->cs_defcflag = (TTYDEF_CFLAG & ~(CSIZE | PARENB)) | CS8;
    831 
    832 	/* Point the console at the SCC. */
    833 	cn_tab = &zs_ioasic_cons;
    834 	cn_tab->cn_pri = CN_REMOTE;
    835 	cn_tab->cn_dev = makedev(cdevsw_lookup_major(&zstty_cdevsw),
    836 				 (zs_offset == 0x100000) ? 0 : 1);
    837 }
    838 
    839 /*
    840  * zs_ioasic_lk201_cnattach --
    841  *	Initialize and attach a keyboard.
    842  */
    843 int
    844 zs_ioasic_lk201_cnattach(ioasic_addr, zs_offset, channel)
    845 	tc_addr_t ioasic_addr;
    846 	tc_offset_t zs_offset;
    847 	int channel;
    848 {
    849 #if (NZSKBD > 0)
    850 	struct zs_chanstate *cs = &zs_ioasic_conschanstate_store;
    851 
    852 	zs_ioasic_cninit(ioasic_addr, zs_offset, channel);
    853 	cs->cs_defspeed = 4800;
    854 	cs->cs_defcflag = (TTYDEF_CFLAG & ~(CSIZE | PARENB)) | CS8;
    855 	return (zskbd_cnattach(cs));
    856 #else
    857 	return (ENXIO);
    858 #endif
    859 }
    860 
    861 int
    862 zs_ioasic_isconsole(offset, channel)
    863 	tc_offset_t offset;
    864 	int channel;
    865 {
    866 
    867 	if (zs_ioasic_console &&
    868 	    offset == zs_ioasic_console_offset &&
    869 	    channel == zs_ioasic_console_channel)
    870 		return (1);
    871 
    872 	return (0);
    873 }
    874 
    875 /*
    876  * Polled console input putchar.
    877  */
    878 int
    879 zs_ioasic_cngetc(dev)
    880 	dev_t dev;
    881 {
    882 
    883 	return (zs_getc(&zs_ioasic_conschanstate_store));
    884 }
    885 
    886 /*
    887  * Polled console output putchar.
    888  */
    889 void
    890 zs_ioasic_cnputc(dev, c)
    891 	dev_t dev;
    892 	int c;
    893 {
    894 
    895 	zs_putc(&zs_ioasic_conschanstate_store, c);
    896 }
    897 
    898 /*
    899  * Set polling/no polling on console.
    900  */
    901 void
    902 zs_ioasic_cnpollc(dev, onoff)
    903 	dev_t dev;
    904 	int onoff;
    905 {
    906 
    907 	/* XXX ??? */
    908 }
    909