dca.c

早期freebsd实现

/*
 * Copyright (c) 1982, 1986, 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 *
 *	@(#)dca.c	8.2 (Berkeley) 1/12/94
 */

#include "dca.h"
#if NDCA > 0
/*
 *  Driver for National Semiconductor INS8250/NS16550AF/WD16C552 UARTs.
 *  Includes:
 *	98626/98644/internal serial interface on hp300/hp400
 *	internal serial ports on hp700
 *
 *  N.B. On the hp700, there is a "secret bit" with undocumented behavior.
 *  The third bit of the Modem Control Register (MCR_IEN == 0x08) must be
 *  set to enable interrupts.
 */
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/ioctl.h>
#include <sys/proc.h>
#include <sys/tty.h>
#include <sys/conf.h>
#include <sys/file.h>
#include <sys/uio.h>
#include <sys/kernel.h>
#include <sys/syslog.h>

#include <hp/dev/device.h>
#include <hp/dev/dcareg.h>

#include <machine/cpu.h>
#ifdef hp300
#include <hp300/hp300/isr.h>
#endif
#ifdef hp700
#include <machine/asp.h>
#endif

int	dcaprobe();
struct	driver dcadriver = {
	dcaprobe, "dca",
};

void	dcastart();
int	dcaparam(), dcaintr();
int	dcasoftCAR;
int	dca_active;
int	dca_hasfifo;
int	ndca = NDCA;
#ifdef DCACONSOLE
int	dcaconsole = DCACONSOLE;
#else
int	dcaconsole = -1;
#endif
int	dcaconsinit;
int	dcadefaultrate = TTYDEF_SPEED;
int	dcamajor;
struct	dcadevice *dca_addr[NDCA];
struct	tty dca_tty[NDCA];
#ifdef hp300
struct	isr dcaisr[NDCA];
int	dcafastservice;
#endif
int	dcaoflows[NDCA];

struct speedtab dcaspeedtab[] = {
	0,	0,
	50,	DCABRD(50),
	75,	DCABRD(75),
	110,	DCABRD(110),
	134,	DCABRD(134),
	150,	DCABRD(150),
	200,	DCABRD(200),
	300,	DCABRD(300),
	600,	DCABRD(600),
	1200,	DCABRD(1200),
	1800,	DCABRD(1800),
	2400,	DCABRD(2400),
	4800,	DCABRD(4800),
	9600,	DCABRD(9600),
	19200,	DCABRD(19200),
	38400,	DCABRD(38400),
	-1,	-1
};

#ifdef KGDB
#include <machine/remote-sl.h>

extern dev_t kgdb_dev;
extern int kgdb_rate;
extern int kgdb_debug_init;
#endif

#define	UNIT(x)		minor(x)

#ifdef DEBUG
long	fifoin[17];
long	fifoout[17];
long	dcaintrcount[16];
long	dcamintcount[16];
#endif

dcaprobe(hd)
	register struct hp_device *hd;
{
	register struct dcadevice *dca;
	register int unit;

	dca = (struct dcadevice *)hd->hp_addr;
#ifdef hp300
	if (dca->dca_id != DCAID0 &&
	    dca->dca_id != DCAREMID0 &&
	    dca->dca_id != DCAID1 &&
	    dca->dca_id != DCAREMID1)
		return (0);
#endif
	unit = hd->hp_unit;
	if (unit == dcaconsole)
		DELAY(100000);
#ifdef hp300
	dca->dca_reset = 0xFF;
	DELAY(100);
#endif

	/* look for a NS 16550AF UART with FIFOs */
	dca->dca_fifo = FIFO_ENABLE|FIFO_RCV_RST|FIFO_XMT_RST|FIFO_TRIGGER_14;
	DELAY(100);
	if ((dca->dca_iir & IIR_FIFO_MASK) == IIR_FIFO_MASK)
		dca_hasfifo |= 1 << unit;

	dca_addr[unit] = dca;
#ifdef hp300
	hd->hp_ipl = DCAIPL(dca->dca_ic);
	dcaisr[unit].isr_ipl = hd->hp_ipl;
	dcaisr[unit].isr_arg = unit;
	dcaisr[unit].isr_intr = dcaintr;
	isrlink(&dcaisr[unit]);
#endif
	dca_active |= 1 << unit;
	if (hd->hp_flags)
		dcasoftCAR |= (1 << unit);
#ifdef KGDB
	if (kgdb_dev == makedev(dcamajor, unit)) {
		if (dcaconsole == unit)
			kgdb_dev = NODEV; /* can't debug over console port */
		else {
			(void) dcainit(unit, kgdb_rate);
			dcaconsinit = 1;	/* don't re-init in dcaputc */
			if (kgdb_debug_init) {
				/*
				 * Print prefix of device name,
				 * let kgdb_connect print the rest.
				 */
				printf("dca%d: ", unit);
				kgdb_connect(1);
			} else
				printf("dca%d: kgdb enabled\n", unit);
		}
	}
#endif
#ifdef hp300
	dca->dca_ic = IC_IE;
#endif
	/*
	 * Need to reset baud rate, etc. of next print so reset dcaconsinit.
	 * Also make sure console is always "hardwired."
	 */
	if (unit == dcaconsole) {
		dcaconsinit = 0;
		dcasoftCAR |= (1 << unit);
	}
	return (1);
}

/* ARGSUSED */
#ifdef __STDC__
dcaopen(dev_t dev, int flag, int mode, struct proc *p)
#else
dcaopen(dev, flag, mode, p)
	dev_t dev;
	int flag, mode;
	struct proc *p;
#endif
{
	register struct tty *tp;
	register int unit;
	int error = 0;
 
	unit = UNIT(dev);
	if (unit >= NDCA || (dca_active & (1 << unit)) == 0)
		return (ENXIO);
	tp = &dca_tty[unit];
	tp->t_oproc = dcastart;
	tp->t_param = dcaparam;
	tp->t_dev = dev;
	if ((tp->t_state & TS_ISOPEN) == 0) {
		tp->t_state |= TS_WOPEN;
		ttychars(tp);
		if (tp->t_ispeed == 0) {
			tp->t_iflag = TTYDEF_IFLAG;
			tp->t_oflag = TTYDEF_OFLAG;
			tp->t_cflag = TTYDEF_CFLAG;
			tp->t_lflag = TTYDEF_LFLAG;
			tp->t_ispeed = tp->t_ospeed = dcadefaultrate;
		}
		dcaparam(tp, &tp->t_termios);
		ttsetwater(tp);
	} else if (tp->t_state&TS_XCLUDE && p->p_ucred->cr_uid != 0)
		return (EBUSY);
	(void) dcamctl(dev, MCR_DTR | MCR_RTS, DMSET);
	if ((dcasoftCAR & (1 << unit)) || (dcamctl(dev, 0, DMGET) & MSR_DCD))
		tp->t_state |= TS_CARR_ON;
	(void) spltty();
	while ((flag&O_NONBLOCK) == 0 && (tp->t_cflag&CLOCAL) == 0 &&
	       (tp->t_state & TS_CARR_ON) == 0) {
		tp->t_state |= TS_WOPEN;
		if (error = ttysleep(tp, (caddr_t)&tp->t_rawq, TTIPRI | PCATCH,
		    ttopen, 0))
			break;
	}
	(void) spl0();
	if (error == 0)
		error = (*linesw[tp->t_line].l_open)(dev, tp);
#ifdef hp300
	/*
	 * XXX hack to speed up unbuffered builtin port.
	 * If dca_fastservice is set, a level 5 interrupt
	 * will be directed to dcaintr first.
	 */
	if (error == 0 && unit == 0 && (dca_hasfifo & 1) == 0)
		dcafastservice = 1;
#endif
	return (error);
}
 
/*ARGSUSED*/
dcaclose(dev, flag, mode, p)
	dev_t dev;
	int flag, mode;
	struct proc *p;
{
	register struct tty *tp;
	register struct dcadevice *dca;
	register int unit;
 
	unit = UNIT(dev);
#ifdef hp300
	if (unit == 0)
		dcafastservice = 0;
#endif
	dca = dca_addr[unit];
	tp = &dca_tty[unit];
	(*linesw[tp->t_line].l_close)(tp, flag);
	dca->dca_cfcr &= ~CFCR_SBREAK;
#ifdef KGDB
	/* do not disable interrupts if debugging */
	if (dev != kgdb_dev)
#endif
	dca->dca_ier = 0;
	if (tp->t_cflag&HUPCL || tp->t_state&TS_WOPEN ||
	    (tp->t_state&TS_ISOPEN) == 0)
		(void) dcamctl(dev, 0, DMSET);
	ttyclose(tp);
	return (0);
}
 
dcaread(dev, uio, flag)
	dev_t dev;
	struct uio *uio;
	int flag;
{
	int unit = UNIT(dev);
	register struct tty *tp = &dca_tty[unit];
	int error, of;
 
	of = dcaoflows[unit];
	error = (*linesw[tp->t_line].l_read)(tp, uio, flag);
	/*
	 * XXX hardly a reasonable thing to do, but reporting overflows
	 * at interrupt time just exacerbates the problem.
	 */
	if (dcaoflows[unit] != of)
		log(LOG_WARNING, "dca%d: silo overflow\n", unit);
	return (error);
}
 
dcawrite(dev, uio, flag)
	dev_t dev;
	struct uio *uio;
	int flag;
{
	int unit = UNIT(dev);
	register struct tty *tp = &dca_tty[unit];
	extern struct tty *constty;
 
	/*
	 * (XXX) We disallow virtual consoles if the physical console is
	 * a serial port.  This is in case there is a display attached that
	 * is not the console.  In that situation we don't need/want the X
	 * server taking over the console.
	 */
	if (constty && unit == dcaconsole)
		constty = NULL;
	return ((*linesw[tp->t_line].l_write)(tp, uio, flag));
}
 
dcaintr(unit)
	register int unit;
{
	register struct dcadevice *dca;
	register u_char code;
	register struct tty *tp;
	int iflowdone = 0;

	dca = dca_addr[unit];
#ifdef hp300
	if ((dca->dca_ic & (IC_IR|IC_IE)) != (IC_IR|IC_IE))
		return (0);
#endif
	tp = &dca_tty[unit];
	while (1) {
		code = dca->dca_iir;
#ifdef DEBUG
		dcaintrcount[code & IIR_IMASK]++;
#endif
		switch (code & IIR_IMASK) {
		case IIR_NOPEND:
			return (1);
		case IIR_RXTOUT:
		case IIR_RXRDY:
			/* do time-critical read in-line */
/*
 * Process a received byte.  Inline for speed...
 */
#ifdef KGDB
#define	RCVBYTE() \
			code = dca->dca_data; \
			if ((tp->t_state & TS_ISOPEN) == 0) { \
				if (code == FRAME_END && \
				    kgdb_dev == makedev(dcamajor, unit)) \
					kgdb_connect(0); /* trap into kgdb */ \
			} else \
				(*linesw[tp->t_line].l_rint)(code, tp)
#else
#define	RCVBYTE() \
			code = dca->dca_data; \
			if ((tp->t_state & TS_ISOPEN) != 0) \
				(*linesw[tp->t_line].l_rint)(code, tp)
#endif
			RCVBYTE();
			if (dca_hasfifo & (1 << unit)) {
#ifdef DEBUG
				register int fifocnt = 1;
#endif
				while ((code = dca->dca_lsr) & LSR_RCV_MASK) {
					if (code == LSR_RXRDY) {
						RCVBYTE();
					} else
						dcaeint(unit, code, dca);
#ifdef DEBUG
					fifocnt++;
#endif
				}
#ifdef DEBUG
				if (fifocnt > 16)
					fifoin[0]++;
				else
					fifoin[fifocnt]++;
#endif
			}
			if (!iflowdone && (tp->t_cflag&CRTS_IFLOW) &&
			    tp->t_rawq.c_cc > TTYHOG/2) {
				dca->dca_mcr &= ~MCR_RTS;
				iflowdone = 1;
			}
			break;
		case IIR_TXRDY:
			tp->t_state &=~ (TS_BUSY|TS_FLUSH);
			if (tp->t_line)
				(*linesw[tp->t_line].l_start)(tp);
			else
				dcastart(tp);
			break;
		case IIR_RLS:
			dcaeint(unit, dca->dca_lsr, dca);
			break;
		default:
			if (code & IIR_NOPEND)
				return (1);
			log(LOG_WARNING, "dca%d: weird interrupt: 0x%x\n",
			    unit, code);
			/* fall through */
		case IIR_MLSC:
			dcamint(unit, dca);
			break;
		}
	}
}

dcaeint(unit, stat, dca)
	register int unit, stat;
	register struct dcadevice *dca;
{
	register struct tty *tp;
	register int c;