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zs.c revision 1.30.34.1
      1 /*	$NetBSD: zs.c,v 1.30.34.1 2012/04/17 00:06:43 yamt 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  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 /*
     33  * Zilog Z8530 Dual UART driver (machine-dependent part)
     34  *
     35  * Runs two serial lines per chip using slave drivers.
     36  * Plain tty/async lines use the zs_async slave.
     37  */
     38 
     39 /*
     40  * news68k/dev/zs.c - based on {newsmips,x68k,mvme68k}/dev/zs.c
     41  */
     42 
     43 #include <sys/cdefs.h>
     44 __KERNEL_RCSID(0, "$NetBSD: zs.c,v 1.30.34.1 2012/04/17 00:06:43 yamt Exp $");
     45 
     46 #include "opt_ddb.h"
     47 
     48 #include <sys/param.h>
     49 #include <sys/systm.h>
     50 #include <sys/conf.h>
     51 #include <sys/device.h>
     52 #include <sys/tty.h>
     53 #include <sys/cpu.h>
     54 #include <sys/intr.h>
     55 
     56 #include <machine/z8530var.h>
     57 
     58 #include <dev/cons.h>
     59 #include <dev/ic/z8530reg.h>
     60 
     61 #include <news68k/dev/hbvar.h>
     62 
     63 #include "ioconf.h"
     64 
     65 int  zs_getc(void *);
     66 void zs_putc(void *, int);
     67 
     68 /*
     69  * Some warts needed by z8530tty.c -
     70  * The default parity REALLY needs to be the same as the PROM uses,
     71  * or you can not see messages done with printf during boot-up...
     72  */
     73 int zs_def_cflag = (CREAD | CS8 | HUPCL);
     74 
     75 /*
     76  * The news68k machines use three different clocks for the ZS chips.
     77  */
     78 #define NPCLK	3
     79 #define PCLK0	(9600 * 416)	/*  news1700: 3.9936MHz */
     80 #define PCLK1	(9600 * 512)	/*  news1200: 4.9152MHz */
     81 #define PCLK2	(9600 * 384)	/*  external: 3.6864MHz */
     82 
     83 static const u_int pclk[NPCLK] = {
     84 	PCLK0,
     85 	PCLK1,
     86 	PCLK2,
     87 };
     88 
     89 /*
     90  * Define interrupt levels.
     91  */
     92 #define ZSHARD_PRI 5
     93 #define ZS_IVECT 64
     94 
     95 #define ZS_DELAY() /* delay(2) */
     96 
     97 /* The layout of this is hardware-dependent (padding, order). */
     98 struct zschan {
     99 	volatile uint8_t zc_csr;	/* ctrl,status, and indirect access */
    100 	volatile uint8_t zc_data;	/* data */
    101 };
    102 struct zsdevice {
    103 	/* Yes, they are backwards. */
    104 	struct	zschan zs_chan_b;
    105 	struct	zschan zs_chan_a;
    106 };
    107 
    108 /* Default speed for all channels */
    109 static int zs_defspeed = 9600;
    110 
    111 /* console status from cninit */
    112 static struct zs_chanstate zs_conschan_store;
    113 static struct zs_chanstate *zs_conschan;
    114 static struct zschan *zc_cons;
    115 
    116 static uint8_t zs_init_reg[16] = {
    117 	0,	/* 0: CMD (reset, etc.) */
    118 	0,	/* 1: No interrupts yet. */
    119 	ZS_IVECT,	/* IVECT */
    120 	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
    121 	ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP,
    122 	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
    123 	0,	/* 6: TXSYNC/SYNCLO */
    124 	0,	/* 7: RXSYNC/SYNCHI */
    125 	0,	/* 8: alias for data port */
    126 	ZSWR9_MASTER_IE,
    127 	0,	/*10: Misc. TX/RX control bits */
    128 	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD,
    129 	BPS_TO_TCONST((PCLK0/16), 9600), /*12: BAUDLO (default=9600) */
    130 	0,			/*13: BAUDHI (default=9600) */
    131 	ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK,
    132 	ZSWR15_BREAK_IE,
    133 };
    134 
    135 
    136 /****************************************************************
    137  * Autoconfig
    138  ****************************************************************/
    139 
    140 /* Definition of the driver for autoconfig. */
    141 static int  zs_match(device_t, cfdata_t, void *);
    142 static void zs_attach(device_t, device_t, void *);
    143 static int  zs_print(void *, const char *name);
    144 
    145 CFATTACH_DECL_NEW(zsc, sizeof(struct zsc_softc),
    146     zs_match, zs_attach, NULL, NULL);
    147 
    148 static int zshard(void *);
    149 #if 0
    150 static int zs_get_speed(struct zs_chanstate *);
    151 #endif
    152 
    153 /*
    154  * Is the zs chip present?
    155  */
    156 static int
    157 zs_match(device_t parent, cfdata_t cf, void *aux)
    158 {
    159 	struct hb_attach_args *ha = aux;
    160 	u_int addr;
    161 
    162 	if (strcmp(ha->ha_name, "zsc"))
    163 		return 0;
    164 
    165 	/* XXX no default address */
    166 	if (ha->ha_address == (u_int)-1)
    167 		return 0;
    168 
    169 	addr = (ha->ha_address);
    170 	/* This returns -1 on a fault (bus error). */
    171 	if (badaddr((void *)addr, 1))
    172 		return 0;
    173 
    174 	return 1;
    175 }
    176 
    177 /*
    178  * Attach a found zs.
    179  */
    180 static void
    181 zs_attach(device_t parent, device_t self, void *aux)
    182 {
    183 	struct zsc_softc *zsc = device_private(self);
    184 	struct cfdata *cf = device_cfdata(self);
    185 	struct hb_attach_args *ha = aux;
    186 	struct zsc_attach_args zsc_args;
    187 	struct zsdevice *zs;
    188 	struct zschan *zc;
    189 	struct zs_chanstate *cs;
    190 	int s, channel, clk;
    191 
    192 	zsc->zsc_dev = self;
    193 
    194 	zs = (void *)(ha->ha_address);
    195 
    196 	clk = cf->cf_flags;
    197 	if (clk < 0 || clk >= NPCLK)
    198 		clk = 0;
    199 
    200 	aprint_normal("\n");
    201 
    202 	/*
    203 	 * Initialize software state for each channel.
    204 	 */
    205 	for (channel = 0; channel < 2; channel++) {
    206 		zsc_args.channel = channel;
    207 		cs = &zsc->zsc_cs_store[channel];
    208 
    209 		zsc->zsc_cs[channel] = cs;
    210 		zc = (channel == 0) ? &zs->zs_chan_a : &zs->zs_chan_b;
    211 
    212 		if (ha->ha_vect != -1)
    213 			zs_init_reg[2] = ha->ha_vect;
    214 
    215 		if (zc == zc_cons) {
    216 			memcpy(cs, zs_conschan, sizeof(struct zs_chanstate));
    217 			zs_conschan = cs;
    218 			zsc_args.hwflags = ZS_HWFLAG_CONSOLE;
    219 		} else {
    220 			cs->cs_reg_csr  = &zc->zc_csr;
    221 			cs->cs_reg_data = &zc->zc_data;
    222 			memcpy(cs->cs_creg, zs_init_reg, 16);
    223 			memcpy(cs->cs_preg, zs_init_reg, 16);
    224 			cs->cs_defspeed = zs_defspeed;
    225 			zsc_args.hwflags = 0;
    226 		}
    227 
    228 		zs_lock_init(cs);
    229 		cs->cs_defcflag = zs_def_cflag;
    230 
    231 		cs->cs_channel = channel;
    232 		cs->cs_private = NULL;
    233 		cs->cs_ops = &zsops_null;
    234 		cs->cs_brg_clk = pclk[clk] / 16;
    235 
    236 		/* Make these correspond to cs_defcflag (-crtscts) */
    237 		cs->cs_rr0_dcd = ZSRR0_DCD;
    238 		cs->cs_rr0_cts = 0;
    239 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
    240 		cs->cs_wr5_rts = 0;
    241 
    242 		/*
    243 		 * Clear the master interrupt enable.
    244 		 * The INTENA is common to both channels,
    245 		 * so just do it on the A channel.
    246 		 */
    247 		if (channel == 0) {
    248 			s = splhigh();
    249 			zs_write_reg(cs, 9, 0);
    250 			splx(s);
    251 		}
    252 
    253 		/*
    254 		 * Look for a child driver for this channel.
    255 		 * The child attach will setup the hardware.
    256 		 */
    257 		if (!config_found(self, (void *)&zsc_args, zs_print)) {
    258 			/* No sub-driver.  Just reset it. */
    259 			uint8_t reset = (channel == 0) ?
    260 				ZSWR9_A_RESET : ZSWR9_B_RESET;
    261 			s = splhigh();
    262 			zs_write_reg(cs,  9, reset);
    263 			splx(s);
    264 		}
    265 	}
    266 
    267 	/*
    268 	 * Now safe to install interrupt handlers.
    269 	 */
    270 	hb_intr_establish(zs_init_reg[2], zshard, ZSHARD_PRI, zsc);
    271 	zsc->zsc_softintr_cookie = softint_establish(SOFTINT_SERIAL,
    272 	    (void (*)(void *))zsc_intr_soft, zsc);
    273 
    274 	/*
    275 	 * Set the master interrupt enable and interrupt vector.
    276 	 * (common to both channels, do it on A)
    277 	 */
    278 	cs = zsc->zsc_cs[0];
    279 	s = splhigh();
    280 	/* interrupt vector */
    281 	zs_write_reg(cs, 2, zs_init_reg[2]);
    282 	/* master interrupt control (enable) */
    283 	zs_write_reg(cs, 9, zs_init_reg[9]);
    284 	splx(s);
    285 
    286 }
    287 
    288 static int
    289 zs_print(void *aux, const char *name)
    290 {
    291 	struct zsc_attach_args *args = aux;
    292 
    293 	if (name != NULL)
    294 		aprint_normal("%s: ", name);
    295 
    296 	if (args->channel != -1)
    297 		aprint_normal(" channel %d", args->channel);
    298 
    299 	return UNCONF;
    300 }
    301 
    302 /*
    303  * For news68k-port, we don't use autovectored interrupt.
    304  * We do not need to look at all of the zs chips.
    305  */
    306 static int
    307 zshard(void *arg)
    308 {
    309 	struct zsc_softc *zsc = arg;
    310 	int rval;
    311 
    312 	rval = zsc_intr_hard(zsc);
    313 
    314 	/* We are at splzs here, so no need to lock. */
    315 	if (zsc->zsc_cs[0]->cs_softreq || zsc->zsc_cs[1]->cs_softreq) {
    316 		softint_schedule(zsc->zsc_softintr_cookie);
    317 	}
    318 
    319 	return rval;
    320 }
    321 
    322 /*
    323  * Compute the current baud rate given a ZS channel.
    324  */
    325 #if 0
    326 static int
    327 zs_get_speed(struct zs_chanstate *cs)
    328 {
    329 	int tconst;
    330 
    331 	tconst = zs_read_reg(cs, 12);
    332 	tconst |= zs_read_reg(cs, 13) << 8;
    333 	return TCONST_TO_BPS(cs->cs_brg_clk, tconst);
    334 }
    335 #endif
    336 
    337 /*
    338  * MD functions for setting the baud rate and control modes.
    339  */
    340 int
    341 zs_set_speed(struct zs_chanstate *cs, int bps)
    342 {
    343 	int tconst, real_bps;
    344 
    345 	if (bps == 0)
    346 		return 0;
    347 
    348 #ifdef	DIAGNOSTIC
    349 	if (cs->cs_brg_clk == 0)
    350 		panic("zs_set_speed");
    351 #endif
    352 
    353 	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
    354 	if (tconst < 0)
    355 		return EINVAL;
    356 
    357 	/* Convert back to make sure we can do it. */
    358 	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);
    359 
    360 	/* XXX - Allow some tolerance here? */
    361 	if (real_bps != bps)
    362 		return EINVAL;
    363 
    364 	cs->cs_preg[12] = tconst;
    365 	cs->cs_preg[13] = tconst >> 8;
    366 
    367 	/* Caller will stuff the pending registers. */
    368 	return 0;
    369 }
    370 
    371 int
    372 zs_set_modes(struct zs_chanstate *cs, int cflag)
    373 {
    374 	int s;
    375 
    376 	/*
    377 	 * Output hardware flow control on the chip is horrendous:
    378 	 * if carrier detect drops, the receiver is disabled, and if
    379 	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
    380 	 * Therefore, NEVER set the HFC bit, and instead use the
    381 	 * status interrupt to detect CTS changes.
    382 	 */
    383 	s = splzs();
    384 	cs->cs_rr0_pps = 0;
    385 	if ((cflag & (CLOCAL | MDMBUF)) != 0) {
    386 		cs->cs_rr0_dcd = 0;
    387 		if ((cflag & MDMBUF) == 0)
    388 			cs->cs_rr0_pps = ZSRR0_DCD;
    389 	} else
    390 		cs->cs_rr0_dcd = ZSRR0_DCD;
    391 	if ((cflag & CRTSCTS) != 0) {
    392 		cs->cs_wr5_dtr = ZSWR5_DTR;
    393 		cs->cs_wr5_rts = ZSWR5_RTS;
    394 		cs->cs_rr0_cts = ZSRR0_CTS;
    395 	} else if ((cflag & MDMBUF) != 0) {
    396 		cs->cs_wr5_dtr = 0;
    397 		cs->cs_wr5_rts = ZSWR5_DTR;
    398 		cs->cs_rr0_cts = ZSRR0_DCD;
    399 	} else {
    400 		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
    401 		cs->cs_wr5_rts = 0;
    402 		cs->cs_rr0_cts = 0;
    403 	}
    404 	splx(s);
    405 
    406 	/* Caller will stuff the pending registers. */
    407 	return 0;
    408 }
    409 
    410 
    411 /*
    412  * Read or write the chip with suitable delays.
    413  */
    414 
    415 uint8_t
    416 zs_read_reg(struct zs_chanstate *cs, uint8_t reg)
    417 {
    418 	uint8_t val;
    419 
    420 	*cs->cs_reg_csr = reg;
    421 	ZS_DELAY();
    422 	val = *cs->cs_reg_csr;
    423 	ZS_DELAY();
    424 	return val;
    425 }
    426 
    427 void
    428 zs_write_reg(struct zs_chanstate *cs, uint8_t reg, uint8_t val)
    429 {
    430 
    431 	*cs->cs_reg_csr = reg;
    432 	ZS_DELAY();
    433 	*cs->cs_reg_csr = val;
    434 	ZS_DELAY();
    435 }
    436 
    437 uint8_t
    438 zs_read_csr(struct zs_chanstate *cs)
    439 {
    440 	uint8_t val;
    441 
    442 	val = *cs->cs_reg_csr;
    443 	ZS_DELAY();
    444 	return val;
    445 }
    446 
    447 void
    448 zs_write_csr(struct zs_chanstate *cs, uint8_t val)
    449 {
    450 
    451 	*cs->cs_reg_csr = val;
    452 	ZS_DELAY();
    453 }
    454 
    455 uint8_t
    456 zs_read_data(struct zs_chanstate *cs)
    457 {
    458 	uint8_t val;
    459 
    460 	val = *cs->cs_reg_data;
    461 	ZS_DELAY();
    462 	return val;
    463 }
    464 
    465 void
    466 zs_write_data(struct zs_chanstate *cs, uint8_t val)
    467 {
    468 
    469 	*cs->cs_reg_data = val;
    470 	ZS_DELAY();
    471 }
    472 
    473 void
    474 zs_abort(struct zs_chanstate *cs)
    475 {
    476 
    477 #ifdef DDB
    478 	Debugger();
    479 #endif
    480 }
    481 
    482 /*
    483  * Polled input char.
    484  */
    485 int
    486 zs_getc(void *arg)
    487 {
    488 	struct zs_chanstate *cs = arg;
    489 	int s, c, rr0;
    490 
    491 	s = splhigh();
    492 	/* Wait for a character to arrive. */
    493 	do {
    494 		rr0 = *cs->cs_reg_csr;
    495 		ZS_DELAY();
    496 	} while ((rr0 & ZSRR0_RX_READY) == 0);
    497 
    498 	c = *cs->cs_reg_data;
    499 	ZS_DELAY();
    500 	splx(s);
    501 
    502 	return c;
    503 }
    504 
    505 /*
    506  * Polled output char.
    507  */
    508 void
    509 zs_putc(void *arg, int c)
    510 {
    511 	struct zs_chanstate *cs = arg;
    512 	int s, rr0;
    513 
    514 	s = splhigh();
    515 	/* Wait for transmitter to become ready. */
    516 	do {
    517 		rr0 = *cs->cs_reg_csr;
    518 		ZS_DELAY();
    519 	} while ((rr0 & ZSRR0_TX_READY) == 0);
    520 
    521 	*cs->cs_reg_data = c;
    522 	ZS_DELAY();
    523 	splx(s);
    524 }
    525 
    526 /*****************************************************************/
    527 
    528 static void zscnprobe(struct consdev *);
    529 static void zscninit(struct consdev *);
    530 static int  zscngetc(dev_t);
    531 static void zscnputc(dev_t, int);
    532 
    533 struct consdev consdev_zs = {
    534 	zscnprobe,
    535 	zscninit,
    536 	zscngetc,
    537 	zscnputc,
    538 	nullcnpollc,
    539 	NULL,
    540 	NULL,
    541 	NULL,
    542 	NODEV,
    543 	CN_DEAD
    544 };
    545 
    546 static void
    547 zscnprobe(struct consdev *cn)
    548 {
    549 }
    550 
    551 static void
    552 zscninit(struct consdev *cn)
    553 {
    554 	struct zs_chanstate *cs;
    555 
    556 	extern const struct cdevsw zstty_cdevsw;
    557 	extern int tty00_is_console;
    558 	extern uint32_t sccport0a;
    559 
    560 	cn->cn_dev = makedev(cdevsw_lookup_major(&zstty_cdevsw), 0);
    561 	if (tty00_is_console)
    562 		cn->cn_pri = CN_REMOTE;
    563 	else
    564 		cn->cn_pri = CN_NORMAL;
    565 
    566 	zc_cons = (struct zschan *)sccport0a; /* XXX */
    567 
    568 	zs_conschan = cs = &zs_conschan_store;
    569 
    570 	/* Setup temporary chanstate. */
    571 	cs->cs_reg_csr  = &zc_cons->zc_csr;
    572 	cs->cs_reg_data = &zc_cons->zc_data;
    573 
    574 	/* Initialize the pending registers. */
    575 	memcpy(cs->cs_preg, zs_init_reg, 16);
    576 	cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS;
    577 
    578 	cs->cs_preg[12] = BPS_TO_TCONST(pclk[systype] / 16, 9600); /* XXX */
    579 	cs->cs_preg[13] = 0;
    580 	cs->cs_defspeed = 9600;
    581 
    582 	/* Clear the master interrupt enable. */
    583 	zs_write_reg(cs, 9, 0);
    584 
    585 	/* Reset the whole SCC chip. */
    586 	zs_write_reg(cs, 9, ZSWR9_HARD_RESET);
    587 
    588 	/* Copy "pending" to "current" and H/W */
    589 	zs_loadchannelregs(cs);
    590 }
    591 
    592 static int
    593 zscngetc(dev_t dev)
    594 {
    595 
    596 	return zs_getc((void *)zs_conschan);
    597 }
    598 
    599 static void
    600 zscnputc(dev_t dev, int c)
    601 {
    602 
    603 	zs_putc((void *)zs_conschan, c);
    604 }
    605