Home | History | Annotate | Line # | Download | only in dev
zs.c revision 1.26
      1 /*	$NetBSD: zs.c,v 1.26 2000/11/21 11:41:37 scw 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  *
     45  * Modified for NetBSD/mvme68k by Jason R. Thorpe <thorpej (at) NetBSD.ORG>
     46  */
     47 
     48 #include <sys/param.h>
     49 #include <sys/systm.h>
     50 #include <sys/conf.h>
     51 #include <sys/device.h>
     52 #include <sys/file.h>
     53 #include <sys/ioctl.h>
     54 #include <sys/kernel.h>
     55 #include <sys/proc.h>
     56 #include <sys/tty.h>
     57 #include <sys/time.h>
     58 #include <sys/syslog.h>
     59 
     60 #include <dev/cons.h>
     61 #include <dev/ic/z8530reg.h>
     62 #include <machine/z8530var.h>
     63 
     64 #include <machine/cpu.h>
     65 #include <machine/bus.h>
     66 #include <machine/intr.h>
     67 
     68 #include <mvme68k/dev/zsvar.h>
     69 
     70 /*
     71  * Some warts needed by z8530tty.c -
     72  * The default parity REALLY needs to be the same as the PROM uses,
     73  * or you can not see messages done with printf during boot-up...
     74  */
     75 int zs_def_cflag = (CREAD | CS8 | HUPCL);
     76 /* XXX Shouldn't hardcode the minor number... */
     77 int zs_major = 12;
     78 
     79 /* Flags from zscnprobe() */
     80 static int zs_hwflags[NZSC][2];
     81 
     82 /* Default speed for each channel */
     83 static int zs_defspeed[NZSC][2] = {
     84 	{ 9600, 	/* port 1 */
     85 	  9600 },	/* port 2 */
     86 	{ 9600, 	/* port 3 */
     87 	  9600 },	/* port 4 */
     88 };
     89 
     90 static struct zs_chanstate zs_conschan_store;
     91 static struct zs_chanstate *zs_conschan;
     92 
     93 u_char zs_init_reg[16] = {
     94 	0,	/* 0: CMD (reset, etc.) */
     95 	0,	/* 1: No interrupts yet. */
     96 	0x18 + ZSHARD_PRI,	/* IVECT */
     97 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
     98 	ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
     99 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
    100 	0,	/* 6: TXSYNC/SYNCLO */
    101 	0,	/* 7: RXSYNC/SYNCHI */
    102 	0,	/* 8: alias for data port */
    103 	ZSWR9_MASTER_IE,
    104 	0,	/*10: Misc. TX/RX control bits */
    105 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
    106 	0,			/*12: BAUDLO (default=9600) */
    107 	0,			/*13: BAUDHI (default=9600) */
    108 	ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
    109 	ZSWR15_BREAK_IE,
    110 };
    111 
    112 
    113 /****************************************************************
    114  * Autoconfig
    115  ****************************************************************/
    116 
    117 /* Definition of the driver for autoconfig. */
    118 static int	zsc_print __P((void *, const char *name));
    119 int	zs_getc __P((void *));
    120 void	zs_putc __P((void *, int));
    121 
    122 #if 0
    123 static int zs_get_speed __P((struct zs_chanstate *));
    124 #endif
    125 
    126 extern struct cfdriver zsc_cd;
    127 
    128 cons_decl(zsc_pcc);
    129 
    130 
    131 /*
    132  * Configure children of an SCC.
    133  */
    134 void
    135 zs_config(zsc, zs, vector, pclk)
    136 	struct zsc_softc *zsc;
    137 	struct zsdevice *zs;
    138 	int vector, pclk;
    139 {
    140 	struct zsc_attach_args zsc_args;
    141 	volatile struct zschan *zc;
    142 	struct zs_chanstate *cs;
    143 	int zsc_unit, channel, s;
    144 
    145 	zsc_unit = zsc->zsc_dev.dv_unit;
    146 	printf(": Zilog 8530 SCC at vector 0x%x\n", vector);
    147 
    148 	/*
    149 	 * Initialize software state for each channel.
    150 	 */
    151 	for (channel = 0; channel < 2; channel++) {
    152 		zsc_args.channel = channel;
    153 		zsc_args.hwflags = zs_hwflags[zsc_unit][channel];
    154 		cs = &zsc->zsc_cs_store[channel];
    155 		zsc->zsc_cs[channel] = cs;
    156 
    157 		/*
    158 		 * If we're the console, copy the channel state, and
    159 		 * adjust the console channel pointer.
    160 		 */
    161 		if (zsc_args.hwflags & ZS_HWFLAG_CONSOLE) {
    162 			bcopy(zs_conschan, cs, sizeof(struct zs_chanstate));
    163 			zs_conschan = cs;
    164 		} else {
    165 			zc = (channel == 0) ? &zs->zs_chan_a : &zs->zs_chan_b;
    166 			cs->cs_reg_csr  = zc->zc_csr;
    167 			cs->cs_reg_data = zc->zc_data;
    168 			bcopy(zs_init_reg, cs->cs_creg, 16);
    169 			bcopy(zs_init_reg, cs->cs_preg, 16);
    170 			cs->cs_defspeed = zs_defspeed[zsc_unit][channel];
    171 		}
    172 
    173 		cs->cs_brg_clk = pclk / 16;
    174 		cs->cs_creg[2] = cs->cs_preg[2] = vector;
    175 		zs_set_speed(cs, cs->cs_defspeed);
    176 		cs->cs_creg[12] = cs->cs_preg[12];
    177 		cs->cs_creg[13] = cs->cs_preg[13];
    178 		cs->cs_defcflag = zs_def_cflag;
    179 
    180 		/* Make these correspond to cs_defcflag (-crtscts) */
    181 		cs->cs_rr0_dcd = ZSRR0_DCD;
    182 		cs->cs_rr0_cts = 0;
    183 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
    184 		cs->cs_wr5_rts = 0;
    185 
    186 		cs->cs_channel = channel;
    187 		cs->cs_private = NULL;
    188 		cs->cs_ops = &zsops_null;
    189 
    190 		/*
    191 		 * Clear the master interrupt enable.
    192 		 * The INTENA is common to both channels,
    193 		 * so just do it on the A channel.
    194 		 * Write the interrupt vector while we're at it.
    195 		 */
    196 		if (channel == 0) {
    197 			zs_write_reg(cs, 9, 0);
    198 			zs_write_reg(cs, 2, vector);
    199 		}
    200 
    201 		/*
    202 		 * Look for a child driver for this channel.
    203 		 * The child attach will setup the hardware.
    204 		 */
    205 		if (!config_found(&zsc->zsc_dev, (void *)&zsc_args, zsc_print)) {
    206 			/* No sub-driver.  Just reset it. */
    207 			u_char reset = (channel == 0) ?
    208 				ZSWR9_A_RESET : ZSWR9_B_RESET;
    209 			s = splzs();
    210 			zs_write_reg(cs,  9, reset);
    211 			splx(s);
    212 		}
    213 	}
    214 
    215 	/*
    216 	 * Allocate a software interrupt cookie.
    217 	 */
    218 	zsc->zsc_softintr_cookie = softintr_establish(IPL_SOFTSERIAL,
    219 	    (void (*)(void *)) zsc_intr_soft, zsc);
    220 #ifdef DEBUG
    221 	assert(zsc->zsc_softintr_cookie);
    222 #endif
    223 }
    224 
    225 static int
    226 zsc_print(aux, name)
    227 	void *aux;
    228 	const char *name;
    229 {
    230 	struct zsc_attach_args *args = aux;
    231 
    232 	if (name != NULL)
    233 		printf("%s: ", name);
    234 
    235 	if (args->channel != -1)
    236 		printf(" channel %d", args->channel);
    237 
    238 	return UNCONF;
    239 }
    240 
    241 #if defined(MVME162) || defined(MVME172)
    242 /*
    243  * Our ZS chips each have their own interrupt vector.
    244  */
    245 int
    246 zshard_unshared(arg)
    247 	void *arg;
    248 {
    249 	struct zsc_softc *zsc = arg;
    250 	int rval;
    251 
    252 	rval = zsc_intr_hard(zsc);
    253 
    254 	if ((zsc->zsc_cs[0]->cs_softreq) || (zsc->zsc_cs[1]->cs_softreq))
    255 		softintr_schedule(zsc->zsc_softintr_cookie);
    256 
    257 	return (rval);
    258 }
    259 #endif
    260 
    261 #ifdef MVME147
    262 /*
    263  * Our ZS chips all share a common, PCC-vectored interrupt,
    264  * so we have to look at all of them on each interrupt.
    265  */
    266 int
    267 zshard_shared(arg)
    268 	void *arg;
    269 {
    270 	struct zsc_softc *zsc;
    271 	int unit, rval;
    272 
    273 	rval = 0;
    274 	for (unit = 0; unit < zsc_cd.cd_ndevs; unit++) {
    275 		zsc = zsc_cd.cd_devs[unit];
    276 		if (zsc == NULL)
    277 			continue;
    278 		rval |= zsc_intr_hard(zsc);
    279 		if ((zsc->zsc_cs[0]->cs_softreq) ||
    280 		    (zsc->zsc_cs[1]->cs_softreq))
    281 			softintr_schedule(zsc->zsc_softintr_cookie);
    282 	}
    283 	return (rval);
    284 }
    285 #endif
    286 
    287 
    288 #if 0
    289 /*
    290  * Compute the current baud rate given a ZSCC channel.
    291  */
    292 static int
    293 zs_get_speed(cs)
    294 	struct zs_chanstate *cs;
    295 {
    296 	int tconst;
    297 
    298 	tconst = zs_read_reg(cs, 12);
    299 	tconst |= zs_read_reg(cs, 13) << 8;
    300 	return (TCONST_TO_BPS(cs->cs_brg_clk, tconst));
    301 }
    302 #endif
    303 
    304 /*
    305  * MD functions for setting the baud rate and control modes.
    306  */
    307 int
    308 zs_set_speed(cs, bps)
    309 	struct zs_chanstate *cs;
    310 	int bps;	/* bits per second */
    311 {
    312 	int tconst, real_bps;
    313 
    314 	if (bps == 0)
    315 		return (0);
    316 
    317 #ifdef	DIAGNOSTIC
    318 	if (cs->cs_brg_clk == 0)
    319 		panic("zs_set_speed");
    320 #endif
    321 
    322 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
    323 	if (tconst < 0)
    324 		return (EINVAL);
    325 
    326 	/* Convert back to make sure we can do it. */
    327 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
    328 
    329 	/* Allow 2% tolerance WRT the required bps */
    330 	if (((abs(real_bps - bps) * 1000) / bps) > 20)
    331 		return (EINVAL);
    332 
    333 	cs->cs_preg[12] = tconst;
    334 	cs->cs_preg[13] = tconst >> 8;
    335 
    336 	/* Caller will stuff the pending registers. */
    337 	return (0);
    338 }
    339 
    340 int
    341 zs_set_modes(cs, cflag)
    342 	struct zs_chanstate *cs;
    343 	int cflag;	/* bits per second */
    344 {
    345 	int s;
    346 
    347 	/*
    348 	 * Output hardware flow control on the chip is horrendous:
    349 	 * if carrier detect drops, the receiver is disabled, and if
    350 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
    351 	 * Therefore, NEVER set the HFC bit, and instead use the
    352 	 * status interrupt to detect CTS changes.
    353 	 */
    354 	s = splzs();
    355 	cs->cs_rr0_pps = 0;
    356 	if ((cflag & (CLOCAL | MDMBUF)) != 0) {
    357 		cs->cs_rr0_dcd = 0;
    358 		if ((cflag & MDMBUF) == 0)
    359 			cs->cs_rr0_pps = ZSRR0_DCD;
    360 	} else
    361 		cs->cs_rr0_dcd = ZSRR0_DCD;
    362 	if ((cflag & CRTSCTS) != 0) {
    363 		cs->cs_wr5_dtr = ZSWR5_DTR;
    364 		cs->cs_wr5_rts = ZSWR5_RTS;
    365 		cs->cs_rr0_cts = ZSRR0_CTS;
    366 	} else if ((cflag & MDMBUF) != 0) {
    367 		cs->cs_wr5_dtr = 0;
    368 		cs->cs_wr5_rts = ZSWR5_DTR;
    369 		cs->cs_rr0_cts = ZSRR0_DCD;
    370 	} else {
    371 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
    372 		cs->cs_wr5_rts = 0;
    373 		cs->cs_rr0_cts = 0;
    374 	}
    375 	splx(s);
    376 
    377 	/* Caller will stuff the pending registers. */
    378 	return (0);
    379 }
    380 
    381 
    382 /*
    383  * Read or write the chip with suitable delays.
    384  */
    385 
    386 u_char
    387 zs_read_reg(cs, reg)
    388 	struct zs_chanstate *cs;
    389 	u_char reg;
    390 {
    391 	u_char val;
    392 
    393 	*cs->cs_reg_csr = reg;
    394 	ZS_DELAY();
    395 	val = *cs->cs_reg_csr;
    396 	ZS_DELAY();
    397 	return val;
    398 }
    399 
    400 void
    401 zs_write_reg(cs, reg, val)
    402 	struct zs_chanstate *cs;
    403 	u_char reg, val;
    404 {
    405 	*cs->cs_reg_csr = reg;
    406 	ZS_DELAY();
    407 	*cs->cs_reg_csr = val;
    408 	ZS_DELAY();
    409 }
    410 
    411 u_char zs_read_csr(cs)
    412 	struct zs_chanstate *cs;
    413 {
    414 	u_char val;
    415 
    416 	val = *cs->cs_reg_csr;
    417 	ZS_DELAY();
    418 	return val;
    419 }
    420 
    421 void  zs_write_csr(cs, val)
    422 	struct zs_chanstate *cs;
    423 	u_char val;
    424 {
    425 	*cs->cs_reg_csr = val;
    426 	ZS_DELAY();
    427 }
    428 
    429 u_char zs_read_data(cs)
    430 	struct zs_chanstate *cs;
    431 {
    432 	u_char val;
    433 
    434 	val = *cs->cs_reg_data;
    435 	ZS_DELAY();
    436 	return val;
    437 }
    438 
    439 void  zs_write_data(cs, val)
    440 	struct zs_chanstate *cs;
    441 	u_char val;
    442 {
    443 	*cs->cs_reg_data = val;
    444 	ZS_DELAY();
    445 }
    446 
    447 /****************************************************************
    448  * Console support functions (MVME specific!)
    449  ****************************************************************/
    450 
    451 /*
    452  * Polled input char.
    453  */
    454 int
    455 zs_getc(arg)
    456 	void *arg;
    457 {
    458 	struct zs_chanstate *cs = arg;
    459 	int s, c, rr0, stat;
    460 
    461 	s = splhigh();
    462  top:
    463 	/* Wait for a character to arrive. */
    464 	do {
    465 		rr0 = *cs->cs_reg_csr;
    466 		ZS_DELAY();
    467 	} while ((rr0 & ZSRR0_RX_READY) == 0);
    468 
    469 	/* Read error register. */
    470 	stat = zs_read_reg(cs, 1) & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE);
    471 	if (stat) {
    472 		zs_write_csr(cs, ZSM_RESET_ERR);
    473 		goto top;
    474 	}
    475 
    476 	/* Read character. */
    477 	c = *cs->cs_reg_data;
    478 	ZS_DELAY();
    479 	splx(s);
    480 
    481 	return (c);
    482 }
    483 
    484 /*
    485  * Polled output char.
    486  */
    487 void
    488 zs_putc(arg, c)
    489 	void *arg;
    490 	int c;
    491 {
    492 	struct zs_chanstate *cs = arg;
    493 	int s, rr0;
    494 
    495 	s = splhigh();
    496 	/* Wait for transmitter to become ready. */
    497 	do {
    498 		rr0 = *cs->cs_reg_csr;
    499 		ZS_DELAY();
    500 	} while ((rr0 & ZSRR0_TX_READY) == 0);
    501 
    502 	*cs->cs_reg_data = c;
    503 	ZS_DELAY();
    504 	splx(s);
    505 }
    506 
    507 /*
    508  * Common parts of console init.
    509  */
    510 void
    511 zs_cnconfig(zsc_unit, channel, zs, pclk)
    512 	int zsc_unit, channel;
    513 	struct zsdevice *zs;
    514 	int pclk;
    515 {
    516 	struct zs_chanstate *cs;
    517 	struct zschan *zc;
    518 
    519 	zc = (channel == 0) ? &zs->zs_chan_a : &zs->zs_chan_b;
    520 
    521 	/*
    522 	 * Pointer to channel state.  Later, the console channel
    523 	 * state is copied into the softc, and the console channel
    524 	 * pointer adjusted to point to the new copy.
    525 	 */
    526 	zs_conschan = cs = &zs_conschan_store;
    527 	zs_hwflags[zsc_unit][channel] = ZS_HWFLAG_CONSOLE;
    528 
    529 	/* Setup temporary chanstate. */
    530 	cs->cs_brg_clk = pclk / 16;
    531 	cs->cs_reg_csr  = zc->zc_csr;
    532 	cs->cs_reg_data = zc->zc_data;
    533 
    534 	/* Initialize the pending registers. */
    535 	bcopy(zs_init_reg, cs->cs_preg, 16);
    536 	cs->cs_preg[5] |= (ZSWR5_DTR | ZSWR5_RTS);
    537 
    538 #if 0
    539 	/* XXX: Preserve BAUD rate from boot loader. */
    540 	/* XXX: Also, why reset the chip here? -gwr */
    541 	cs->cs_defspeed = zs_get_speed(cs);
    542 #else
    543 	cs->cs_defspeed = 9600;	/* XXX */
    544 #endif
    545 	zs_set_speed(cs, cs->cs_defspeed);
    546 	cs->cs_creg[12] = cs->cs_preg[12];
    547 	cs->cs_creg[13] = cs->cs_preg[13];
    548 
    549 	/* Clear the master interrupt enable. */
    550 	zs_write_reg(cs, 9, 0);
    551 
    552 	/* Reset the whole SCC chip. */
    553 	zs_write_reg(cs, 9, ZSWR9_HARD_RESET);
    554 
    555 	/* Copy "pending" to "current" and H/W. */
    556 	zs_loadchannelregs(cs);
    557 }
    558 
    559 /*
    560  * Polled console input putchar.
    561  */
    562 int
    563 zsc_pcccngetc(dev)
    564 	dev_t dev;
    565 {
    566 	struct zs_chanstate *cs = zs_conschan;
    567 	int c;
    568 
    569 	c = zs_getc(cs);
    570 	return (c);
    571 }
    572 
    573 /*
    574  * Polled console output putchar.
    575  */
    576 void
    577 zsc_pcccnputc(dev, c)
    578 	dev_t dev;
    579 	int c;
    580 {
    581 	struct zs_chanstate *cs = zs_conschan;
    582 
    583 	zs_putc(cs, c);
    584 }
    585 
    586 /*
    587  * Handle user request to enter kernel debugger.
    588  */
    589 void
    590 zs_abort(cs)
    591 	struct zs_chanstate *cs;
    592 {
    593 	int rr0;
    594 
    595 	/* Wait for end of break to avoid PROM abort. */
    596 	/* XXX - Limit the wait? */
    597 	do {
    598 		rr0 = *cs->cs_reg_csr;
    599 		ZS_DELAY();
    600 	} while (rr0 & ZSRR0_BREAK);
    601 
    602 	mvme68k_abort("SERIAL LINE ABORT");
    603 }
    604