path: root/sys/arch/sgi/hpc/zs.c

/*	$OpenBSD: zs.c,v 1.8 2012/04/29 09:01:38 miod Exp $	*/
/*	$NetBSD: zs.c,v 1.37 2011/02/20 07:59:50 matt Exp $	*/

/*-
 * Copyright (c) 1996, 2000 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Gordon W. Ross and Wayne Knowles
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Zilog Z8530 Dual UART driver (machine-dependent part)
 *
 * Runs two serial lines per chip using slave drivers.
 * Plain tty/async lines use the zs_async slave.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/device.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/tty.h>
#include <sys/time.h>
#include <sys/syslog.h>

#include <mips64/archtype.h>
#include <mips64/arcbios.h>

#include <machine/autoconf.h>
#include <machine/cpu.h>
#include <machine/z8530var.h>

#include <dev/cons.h>

#include <dev/ic/z8530reg.h>

#include <sgi/hpc/hpcvar.h>
#include <sgi/hpc/hpcreg.h>

/*
 * Some warts needed by z8530tty.c -
 * The default parity REALLY needs to be the same as the PROM uses,
 * or you can not see messages done with printf during boot-up...
 */
int zs_def_cflag = (CREAD | CS8 | HUPCL);
int zs_major = 19;

#define PCLK		3672000	 /* PCLK pin input clock rate */

#ifndef ZS_DEFSPEED
#define ZS_DEFSPEED	9600
#endif

/*
 * Define interrupt levels.
 */
#define ZSHARD_PRI 64

/* SGI shouldn't need ZS_DELAY() as recovery time is done in hardware? */
#define ZS_DELAY()	delay(2)

/* The layout of this is hardware-dependent (padding, order). */
struct zschan {
	uint8_t pad1[3];
	volatile uint8_t zc_csr;	/* ctrl,status, and indirect access */
	uint8_t pad2[3];
	volatile uint8_t zc_data;	/* data */
};

struct zsdevice {
	struct	zschan zs_chan_b;
	struct	zschan zs_chan_a;
};

/* Return the byte offset of element within a structure */
#define OFFSET(struct_def, el)		((size_t)&((struct_def *)0)->el)

#define ZS_CHAN_A	OFFSET(struct zsdevice, zs_chan_a)
#define ZS_CHAN_B	OFFSET(struct zsdevice, zs_chan_b)
#define ZS_REG_CSR	3
#define ZS_REG_DATA	7
static int zs_chan_offset[] = {ZS_CHAN_A, ZS_CHAN_B};

cons_decl(zs);
struct consdev zs_cn = {
	zscnprobe,
	zscninit,
	zscngetc,
	zscnputc,
	zscnpollc,
	NULL
};


/* Flags from cninit() */
static int zs_consunit = -1;
static int zs_conschan = -1;

/* Default speed for all channels */
static int zs_defspeed = ZS_DEFSPEED;

static uint8_t zs_init_reg[17] = {
	0,				/* 0: CMD (reset, etc.) */
	0,				/* 1: No interrupts yet. */
	ZSHARD_PRI,			/* 2: IVECT */
	ZSWR3_RX_8 | ZSWR3_RX_ENABLE,
	ZSWR4_CLK_X16 | ZSWR4_ONESB,
	ZSWR5_TX_8 | ZSWR5_TX_ENABLE,
	0,				/* 6: TXSYNC/SYNCLO */
	0,				/* 7: RXSYNC/SYNCHI */
	0,				/* 8: alias for data port */
	ZSWR9_MASTER_IE,
	0,				/*10: Misc. TX/RX control bits */
	ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD | ZSWR11_TRXC_OUT_ENA,
	BPS_TO_TCONST(PCLK/16, ZS_DEFSPEED), /*12: BAUDLO (default=9600) */
	0,				/*13: BAUDHI (default=9600) */
	ZSWR14_BAUD_ENA,
	ZSWR15_BREAK_IE,
	ZSWR7P_TX_FIFO			/* 7': TX FIFO interrupt level */
};


/****************************************************************
 * Autoconfig
 ****************************************************************/

/* Definition of the driver for autoconfig. */
int	zs_hpc_match(struct device *, void *, void *);
void	zs_hpc_attach(struct device *, struct device *, void *);
int	zs_print(void *, const char *name);

struct cfdriver zs_cd = {
	NULL, "zs", DV_TTY
};

struct cfattach zs_hpc_ca = {
	sizeof(struct zsc_softc), zs_hpc_match, zs_hpc_attach
};

int		 zshard(void *);
void		 zssoft(void *);
struct zschan	*zs_get_chan_addr(int, int);
int		 zs_getc(void *);
void		 zs_putc(void *, int);

/*
 * Is the zs chip present?
 */
int
zs_hpc_match(struct device *parent, void *vcf, void *aux)
{
	struct cfdata *cf = vcf;
	struct hpc_attach_args *ha = aux;

	if (strcmp(ha->ha_name, cf->cf_driver->cd_name) == 0)
		return (1);

	return (0);
}

/*
 * Attach a found zs.
 *
 * Match slave number to zs unit number, so that misconfiguration will
 * not set up the keyboard as ttya, etc.
 */
void
zs_hpc_attach(struct device *parent, struct device *self, void *aux)
{
	struct zsc_softc *zsc = (void *)self;
	struct cfdata *cf = self->dv_cfdata;
	struct hpc_attach_args *haa = aux;
	struct zsc_attach_args zsc_args;
	struct zs_chanstate *cs;
	struct zs_channel *ch;
	int zs_unit, channel, err, s;
	int has_fifo;

	zsc->zsc_bustag = haa->ha_st;
	if ((err = bus_space_subregion(haa->ha_st, haa->ha_sh,
				       haa->ha_devoff, 0x10,
				       &zsc->zsc_base)) != 0) {
		printf(": unable to map 85c30 registers, error = %d\n",
		    err);
		return;
	}

	zs_unit = zsc->zsc_dev.dv_unit;

	/*
	 * Initialize software state for each channel.
	 *
	 * Done in reverse order of channels since the first serial port
	 * is actually attached to the *second* channel, and vice versa.
	 * Doing it this way should force a 'zstty*' to attach zstty0 to
	 * channel 1 and zstty1 to channel 0.  They couldn't have wired
	 * it up in a more sensible fashion, could they?
	 */
	for (channel = 1; channel >= 0; channel--) {
		zsc_args.channel = channel;
		ch = &zsc->zsc_cs_store[channel];
		cs = zsc->zsc_cs[channel] = (struct zs_chanstate *)ch;

		/* pick Indigo wiring if requested */
		if (cf->cf_flags & ZSCFL_INDIGO_WIRING)
			ch->cs_flags |= ZSCFL_INDIGO_WIRING;

		cs->cs_reg_csr = NULL;
		cs->cs_reg_data = NULL;
		cs->cs_channel = channel;
		cs->cs_private = NULL;
		cs->cs_ops = &zsops_null;
		cs->cs_brg_clk = PCLK / 16;

		if (bus_space_subregion(zsc->zsc_bustag, zsc->zsc_base,
					zs_chan_offset[channel],
					sizeof(struct zschan),
					&ch->cs_regs) != 0) {
			printf(": cannot map regs\n", self->dv_xname);
			return;
		}
		ch->cs_bustag = zsc->zsc_bustag;

		/*
		 * Figure out whether this chip is a 8530 or a 85230.
		 */
		if (channel == 1) {
			zs_write_reg(cs, 15, ZSWR15_ENABLE_ENHANCED);
			has_fifo = zs_read_reg(cs, 15) & ZSWR15_ENABLE_ENHANCED;

			if (has_fifo) {
				zs_write_reg(cs, 15, 0);
				printf(": 85230\n");
			} else
				printf(": 8530\n");
		}

		if (has_fifo)
			zs_init_reg[15] |= ZSWR15_ENABLE_ENHANCED;
		else
			zs_init_reg[15] &= ~ZSWR15_ENABLE_ENHANCED;
		memcpy(cs->cs_creg, zs_init_reg, 17);
		memcpy(cs->cs_preg, zs_init_reg, 17);

		/* If console, don't stomp speed, let zstty know */
		if (zs_unit == zs_consunit && channel == zs_conschan) {
			zsc_args.consdev = &zs_cn;
			zsc_args.hwflags = ZS_HWFLAG_CONSOLE;
			cs->cs_defspeed = bios_consrate;
		} else {
			zsc_args.consdev = NULL;
			zsc_args.hwflags = 0;
			cs->cs_defspeed = zs_defspeed;
		}

		cs->cs_defcflag = zs_def_cflag;

		/* Make these correspond to cs_defcflag (-crtscts) */
		cs->cs_rr0_dcd = ZSRR0_DCD;
		cs->cs_rr0_cts = 0;
		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
		cs->cs_wr5_rts = 0;

		/*
		 * Clear the master interrupt enable.
		 * The INTENA is common to both channels,
		 * so just do it on the A channel.
		 */
		if (channel == 0) {
			zs_write_reg(cs, 9, 0);
		}
		/*
		 * Look for a child driver for this channel.
		 * The child attach will setup the hardware.
		 */
		if (!config_found(self, (void *)&zsc_args, zs_print)) {
			/* No sub-driver.  Just reset it. */
			uint8_t reset = (channel == 0) ?
				ZSWR9_A_RESET : ZSWR9_B_RESET;

			s = splhigh();
			zs_write_reg(cs, 9, reset);
			splx(s);
		}
	}


	zsc->sc_si = softintr_establish(IPL_SOFTTTY, zssoft, zsc);
	hpc_intr_establish(haa->ha_irq, IPL_TTY, zshard, zsc, self->dv_xname);

	/*
	 * Set the master interrupt enable and interrupt vector.
	 * (common to both channels, do it on A)
	 */
	cs = zsc->zsc_cs[0];
	s = splhigh();
	/* interrupt vector */
	zs_write_reg(cs, 2, zs_init_reg[2]);
	/* master interrupt control (enable) */
	zs_write_reg(cs, 9, zs_init_reg[9]);
	splx(s);
}

int
zs_print(void *aux, const char *name)
{
	struct zsc_attach_args *args = aux;

	if (name != NULL)
		printf("%s: ", name);

	if (args->channel != -1)
		printf(" channel %d", args->channel);

	return UNCONF;
}

/*
 * Our ZS chips all share a common, autovectored interrupt,
 * so we have to look at all of them on each interrupt.
 */
int
zshard(void *arg)
{
	struct zsc_softc *zsc = arg;
	int rval;

	rval = zsc_intr_hard(zsc);
	if (rval != 0) {
		if (zsc->zsc_cs[0]->cs_softreq ||
		    zsc->zsc_cs[1]->cs_softreq)
			softintr_schedule(zsc->sc_si);
	}

	return rval;
}

/*
 * Similar scheme as for zshard (look at all of them)
 */
void
zssoft(void *arg)
{
	struct zsc_softc *zsc = arg;
	int s;

	/* Make sure we call the tty layer at spltty. */
	s = spltty();
	(void)zsc_intr_soft(zsc);
	splx(s);
}


/*
 * MD functions for setting the baud rate and control modes.
 */
int
zs_set_speed(struct zs_chanstate *cs, int bps)
{
	int tconst, real_bps;

	if (bps == 0)
		return (0);

#ifdef	DIAGNOSTIC
	if (cs->cs_brg_clk == 0)
		panic("zs_set_speed");
#endif

	tconst = BPS_TO_TCONST(cs->cs_brg_clk, bps);
	if (tconst < 0)
		return (EINVAL);

	/* Convert back to make sure we can do it. */
	real_bps = TCONST_TO_BPS(cs->cs_brg_clk, tconst);

#if 0	/* PCLK is too small, 9600bps really yields 9562 */
	/* XXX - Allow some tolerance here? */
	if (real_bps != bps)
		return (EINVAL);
#endif

	cs->cs_preg[12] = tconst;
	cs->cs_preg[13] = tconst >> 8;

	/* Caller will stuff the pending registers. */
	return (0);
}

int
zs_set_modes(struct zs_chanstate *cs, int cflag)
{
	int s;

	/*
	 * Output hardware flow control on the chip is horrendous:
	 * if carrier detect drops, the receiver is disabled, and if
	 * CTS drops, the transmitter is stoped IN MID CHARACTER!
	 * Therefore, NEVER set the HFC bit, and instead use the
	 * status interrupt to detect CTS changes.
	 */
	s = splzs();
	cs->cs_rr0_pps = 0;
	if ((cflag & (CLOCAL | MDMBUF)) != 0) {
		cs->cs_rr0_dcd = 0;
		if ((cflag & MDMBUF) == 0)
			cs->cs_rr0_pps = ZSRR0_DCD;
	} else
		cs->cs_rr0_dcd = ZSRR0_DCD;
	if ((cflag & CRTSCTS) != 0) {
		cs->cs_wr5_dtr = ZSWR5_DTR;
		cs->cs_wr5_rts = ZSWR5_RTS;
		cs->cs_rr0_cts = ZSRR0_CTS;
	} else if ((cflag & MDMBUF) != 0) {
		cs->cs_wr5_dtr = 0;
		cs->cs_wr5_rts = ZSWR5_DTR;
		cs->cs_rr0_cts = ZSRR0_DCD;
	} else {
		cs->cs_wr5_dtr = ZSWR5_DTR | ZSWR5_RTS;
		cs->cs_wr5_rts = 0;
		cs->cs_rr0_cts = 0;
	}
	splx(s);

	/* Caller will stuff the pending registers. */
	return (0);
}


/*
 * Read or write the chip with suitable delays.
 */

uint8_t
zs_read_reg(struct zs_chanstate *cs, uint8_t reg)
{
	uint8_t val;
	struct zs_channel *zsc = (struct zs_channel *)cs;

	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, reg);
	bus_space_barrier(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, 1,
	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
	ZS_DELAY();
	val = bus_space_read_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR);
	ZS_DELAY();

	/*
	 * According to IRIX <sys/z8530.h>, on Indigo, the CTS and DCD bits
	 * are inverted.
	 */
	if ((zsc->cs_flags & ZSCFL_INDIGO_WIRING) && reg == 0)
		val ^= ZSRR0_CTS | ZSRR0_DCD;

	return val;
}

void
zs_write_reg(struct zs_chanstate *cs, uint8_t reg, uint8_t val)
{
	struct zs_channel *zsc = (struct zs_channel *)cs;

	/*
	 * According to IRIX <sys/z8530.h>, on Indigo, the RTS and DTR bits
	 * are inverted.
	 */
	if ((zsc->cs_flags & ZSCFL_INDIGO_WIRING) && reg == 5)
		val ^= ZSWR5_DTR | ZSWR5_RTS;

	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, reg);
	bus_space_barrier(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, 1,
	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
	ZS_DELAY();
	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, val);
	bus_space_barrier(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, 1,
	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
	ZS_DELAY();
}

uint8_t
zs_read_csr(struct zs_chanstate *cs)
{
	struct zs_channel *zsc = (struct zs_channel *)cs;
	uint8_t val;

	val = bus_space_read_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR);
	ZS_DELAY();

	/*
	 * According to IRIX <sys/z8530.h>, on Indigo, the CTS and DCD bits
	 * are inverted.
	 */
	if (zsc->cs_flags & ZSCFL_INDIGO_WIRING)
		val ^= ZSRR0_CTS | ZSRR0_DCD;

	return val;
}

void
zs_write_csr(struct zs_chanstate *cs, uint8_t val)
{
	struct zs_channel *zsc = (struct zs_channel *)cs;

	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, val);
	bus_space_barrier(zsc->cs_bustag, zsc->cs_regs, ZS_REG_CSR, 1,
	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
	ZS_DELAY();
}

uint8_t
zs_read_data(struct zs_chanstate *cs)
{
	struct zs_channel *zsc = (struct zs_channel *)cs;
	uint8_t val;

	val = bus_space_read_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_DATA);
	ZS_DELAY();
	return val;
}

void
zs_write_data(struct zs_chanstate *cs, uint8_t val)
{
	struct zs_channel *zsc = (struct zs_channel *)cs;

	bus_space_write_1(zsc->cs_bustag, zsc->cs_regs, ZS_REG_DATA, val);
	bus_space_barrier(zsc->cs_bustag, zsc->cs_regs, ZS_REG_DATA, 1,
	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
	ZS_DELAY();
}

void
zs_abort(struct zs_chanstate *cs)
{
#if defined(KGDB)
	zskgdb(cs);
#elif defined(DDB)
	Debugger();
#endif
}


/*********************************************************/
/*  Polled character I/O functions for console and KGDB  */
/*********************************************************/

struct zschan *
zs_get_chan_addr(int zs_unit, int channel)
{
#if 0
	static int dumped_addr = 0;
#endif
	struct zsdevice *addr = NULL;
	struct zschan *zc;

	switch (sys_config.system_type) {
	case SGI_IP20:
		switch (zs_unit) {
		case 0:
			addr = (struct zsdevice *)
			    PHYS_TO_XKPHYS(0x1fb80d00, CCA_NC);
			break;
		case 1:
			addr = (struct zsdevice *)
			    PHYS_TO_XKPHYS(0x1fb80d10, CCA_NC);
			break;
		}
		break;

	case SGI_IP22:
	case SGI_IP26:
	case SGI_IP28:
		if (zs_unit == 0)
			addr = (struct zsdevice *)
			    PHYS_TO_XKPHYS(0x1fbd9830, CCA_NC);
		break;
	}
	if (addr == NULL)
		panic("zs_get_chan_addr: bad zs_unit %d\n", zs_unit);

	/*
	 * We need to swap serial ports to match reality on
	 * non-keyboard channels.
	 */
	if (sys_config.system_type != SGI_IP20) {
		if (channel == 0)
			zc = &addr->zs_chan_b;
		else
			zc = &addr->zs_chan_a;
	} else {
		if (zs_unit == 0) {
			if (channel == 0)
				zc = &addr->zs_chan_a;
			else
				zc = &addr->zs_chan_b;
		} else {
			if (channel == 0)
				zc = &addr->zs_chan_b;
			else
				zc = &addr->zs_chan_a;
		}
	}

#if 0
	if (dumped_addr == 0) {
		dumped_addr++;
		printf("zs unit %d, channel %d had address %p\n",
		    zs_unit, channel, zc);
	}
#endif

	return (zc);
}

int
zs_getc(void *arg)
{
	register volatile struct zschan *zc = arg;
	register int s, c, rr0;

	s = splzs();
	/* Wait for a character to arrive. */
	do {
		rr0 = zc->zc_csr;
		ZS_DELAY();
	} while ((rr0 & ZSRR0_RX_READY) == 0);

	c = zc->zc_data;
	ZS_DELAY();
	splx(s);

	return (c);
}

/*
 * Polled output char.
 */
void
zs_putc(void *arg, int c)
{
	register volatile struct zschan *zc = arg;
	register int s, rr0;

	s = splzs();
	/* Wait for transmitter to become ready. */
	do {
		rr0 = zc->zc_csr;
		ZS_DELAY();
	} while ((rr0 & ZSRR0_TX_READY) == 0);

	zc->zc_data = c;

	/* inline bus_space_barrier() */
	__asm__ __volatile__ ("sync" ::: "memory");
	if (sys_config.system_type != SGI_IP20) {
		(void)*(volatile uint32_t *)PHYS_TO_XKPHYS(HPC_BASE_ADDRESS_0 +
		    HPC3_INTRSTAT_40, CCA_NC);
	}

	ZS_DELAY();
	splx(s);
}

/***************************************************************/

static int  cons_port;

void
zscnprobe(struct consdev *cp)
{
	cp->cn_dev = makedev(zs_major, 0);
	cp->cn_pri = CN_DEAD;

	switch (sys_config.system_type) {
	case SGI_IP20:
	case SGI_IP22:
	case SGI_IP26:
	case SGI_IP28:
		if (strlen(bios_console) == 9 &&
		    strncmp(bios_console, "serial", 6) == 0)
			cp->cn_pri = CN_FORCED;
		else
			cp->cn_pri = CN_MIDPRI;
		break;
	}
}

void
zscninit(struct consdev *cn)
{
	if (strlen(bios_console) == 9 &&
	    strncmp(bios_console, "serial", 6) != 0)
		cons_port = bios_console[7] - '0';

	/* Mark this unit as the console */
	zs_consunit = 0;

	/* SGI hardware wires serial port 1 to channel B, port 2 to A */
	if (cons_port == 0)
		zs_conschan = 1;
	else
		zs_conschan = 0;
}

int
zscngetc(dev_t dev)
{
	struct zschan *zs;

	switch (sys_config.system_type) {
	case SGI_IP20:
		zs = zs_get_chan_addr(1, cons_port);
		break;
	case SGI_IP22:
	case SGI_IP26:
	case SGI_IP28:
	default:
		zs = zs_get_chan_addr(0, cons_port);
		break;
	}

	return zs_getc(zs);
}

void
zscnputc(dev_t dev, int c)
{
	struct zschan *zs;

	switch (sys_config.system_type) {
	case SGI_IP20:
		zs = zs_get_chan_addr(1, cons_port);
		break;
	case SGI_IP22:
	case SGI_IP26:
	case SGI_IP28:
	default:
		zs = zs_get_chan_addr(0, cons_port);
		break;
	}

	zs_putc(zs, c);
}

void
zscnpollc(dev_t dev, int on)
{
}