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Initial import, 0.1 + pk 0.2.4-B1
[unix-history] / sys / i386 / isa / sio.c
/*-
* Copyright (c) 1991 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.
*
* @(#)sio.c 7.5 (Berkeley) 5/16/91
*
* 27 May 93 Bruce Evans From com-0.2 package, fast interrupt
* com port driver.
* 27 May 93 Guido van Rooij Ported in Chris Demetriou's BIDIR
* code, add multiport support.
* 27 May 93 Rodney W. Grimes I then renamed it to sio.c for putting
* into the patch kit. Added in sioselect
* from com.c. Added port 4 support.
*/
static char rcsid[] = "$Header: /usr/bill/working/sys/i386/isa/RCS/com.c,v 1.2 92/01/21 14:34:11 william Exp $";
#include "sio.h"
#if NSIO > 0
/*
* COM driver, based on HP dca driver.
* Mostly rewritten to use pseudo-DMA.
* Works for National Semiconductor NS8250-NS16550AF UARTs.
*/
#include "param.h"
#include "systm.h"
#include "ioctl.h"
#include "tty.h"
#include "proc.h"
#include "user.h"
#include "conf.h"
#include "file.h"
#include "uio.h"
#include "kernel.h"
#include "syslog.h"
#include "i386/isa/isa.h"
#include "i386/isa/isa_device.h"
#include "i386/isa/comreg.h"
#include "i386/isa/ic/ns16550.h"
#undef CRTS_IFLOW
#define CRTS_IFLOW CRTSCTS /* XXX, CCTS_OFLOW = CRTSCTS already */
#define LOTS_OF_EVENTS 64 /* helps separate urgent events from input */
#define RB_I_HIGH_WATER (RBSZ - 2 * RS_IBUFSIZE)
#define RB_I_LOW_WATER ((RBSZ - 2 * RS_IBUFSIZE) * 7 / 8)
#define RS_IBUFSIZE 256
#define TS_RTSBLOCK TS_TBLOCK /* XXX */
#define TTY_BI TTY_FE /* XXX */
#define TTY_OE TTY_PE /* XXX */
#ifndef COM_BIDIR
#define UNIT(x) (minor(x)) /* XXX */
#else /* COM_BIDIR */
#define COM_UNITMASK 0x7f
#define COM_CALLOUTMASK 0x80
#define UNIT(x) (minor(x) & COM_UNITMASK)
#define CALLOUT(x) (minor(x) & COM_CALLOUTMASK)
#endif /* COM_BIDIR */
#ifdef COM_MULTIPORT
/* checks in flags for multiport and which is multiport "master chip"
* for a given card
*/
#define COM_ISMULTIPORT(dev) ((dev)->id_flags & 0x01)
#define COM_MPMASTER(dev) (((dev)->id_flags >> 8) & 0x0ff)
#endif /* COM_MULTIPORT */
#define com_scr 7 /* scratch register for 16450-16550 (R/W) */
#define schedsoftcom() (ipending |= 1 << 4) /* XXX */
/*
* Input buffer watermarks.
* The external device is asked to stop sending when the buffer exactly reaches
* high water, or when the high level requests it.
* The high level is notified immediately (rather than at a later clock tick)
* when this watermark is reached.
* The buffer size is chosen so the watermark should almost never be reached.
* The low watermark is invisibly 0 since the buffer is always emptied all at
* once.
*/
#define RS_IHIGHWATER (3 * RS_IBUFSIZE / 4)
/*
* com state bits.
* (CS_BUSY | CS_TTGO) and (CS_BUSY | CS_TTGO | CS_ODEVREADY) must be higher
* than the other bits so that they can be tested as a group without masking
* off the low bits.
*
* The following com and tty flags correspond closely:
* TS_BUSY = CS_BUSY (maintained by comstart() and comflush())
* CS_TTGO = ~TS_TTSTOP (maintained by comstart() and siostop())
* CS_CTS_OFLOW = CCTS_OFLOW (maintained by comparam())
* CS_RTS_IFLOW = CRTS_IFLOW (maintained by comparam())
* TS_FLUSH is not used.
* Bug: I think TIOCSETA doesn't clear TS_TTSTOP when it clears IXON.
*/
#define CS_BUSY 0x80 /* output in progress */
#define CS_TTGO 0x40 /* output not stopped by XOFF */
#define CS_ODEVREADY 0x20 /* external device h/w ready (CTS) */
#define CS_CHECKMSR 1 /* check of MSR scheduled */
#define CS_CTS_OFLOW 2 /* use CTS output flow control */
#define CS_ODONE 4 /* output completed */
#define CS_RTS_IFLOW 8 /* use RTS input flow control */
static char *error_desc[] = {
#define CE_OVERRUN 0
"silo overflow",
#define CE_INTERRUPT_BUF_OVERFLOW 1
"interrupt-level buffer overflow",
#define CE_TTY_BUF_OVERFLOW 2
"tty-level buffer overflow",
};
#define CE_NTYPES 3
#define CE_RECORD(com, errnum) (++(com)->delta_error_counts[errnum])
/* types. XXX - should be elsewhere */
typedef u_int Port_t; /* hardware port */
typedef int Bool_t; /* promoted boolean */
typedef u_char bool_t; /* boolean */
/* com device structure */
struct com_s {
u_char state; /* miscellaneous flag bits */
u_char cfcr_image; /* copy of value written to CFCR */
bool_t hasfifo; /* nonzero for 16550 UARTs */
u_char mcr_image; /* copy of value written to MCR */
bool_t softDCD; /* nonzero for faked carrier detect */
#ifdef COM_BIDIR
bool_t bidir; /* is this unit bidirectional? */
bool_t active; /* is the port active _at all_? */
bool_t active_in; /* is the incoming port in use? */
bool_t active_out; /* is the outgoing port in use? */
#endif /* COM_BIDIR */
#ifdef COM_MULTIPORT
bool_t multiport; /* is this unit part of a multiport device? */
#endif /* COM_MULTIPORT */
/*
* The high level of the driver never reads status registers directly
* because there would be too many side effects to handle conveniently.
* Instead, it reads copies of the registers stored here by the
* interrupt handler.
*/
u_char last_modem_status; /* last MSR read by intr handler */
u_char prev_modem_status; /* last MSR handled by high level */
u_char *ibuf; /* start of input buffer */
u_char *ibufend; /* end of input buffer */
u_char *ihighwater; /* threshold in input buffer */
u_char *iptr; /* next free spot in input buffer */
u_char *obufend; /* end of output buffer */
int ocount; /* original count for current output */
u_char *optr; /* next char to output */
Port_t data_port; /* i/o ports */
Port_t int_id_port;
Port_t iobase;
Port_t modem_ctl_port;
Port_t line_status_port;
Port_t modem_status_port;
struct tty *tp; /* cross reference */
u_long bytes_in; /* statistics */
u_long bytes_out;
u_int delta_error_counts[CE_NTYPES];
u_int error_counts[CE_NTYPES];
/*
* Ping-pong input buffers. The extra factor of 2 in the sizes is
* to allow for an error byte for each input byte.
*/
#define CE_INPUT_OFFSET RS_IBUFSIZE
u_char ibuf1[2 * RS_IBUFSIZE];
u_char ibuf2[2 * RS_IBUFSIZE];
};
/*
* These functions in the com module ought to be declared (with a prototype)
* in a com-driver system header. The void ones may need to be int to match
* ancient devswitch declarations, but they don't actually return anything.
*/
#define Dev_t int /* promoted dev_t */
struct consdev;
int sioclose __P((Dev_t dev, int fflag, int devtype,
struct proc *p));
void siointr __P((int unit));
#ifdef COM_MULTIPORT
bool_t comintr1 __P((struct com_s *com));
#endif /* COM_MULTIPORT */
int sioioctl __P((Dev_t dev, int cmd, caddr_t data,
int fflag, struct proc *p));
int siocngetc __P((Dev_t dev));
void siocninit __P((struct consdev *cp));
void siocnprobe __P((struct consdev *cp));
void siocnputc __P((Dev_t dev, int c));
int sioopen __P((Dev_t dev, int oflags, int devtype,
struct proc *p));
/*
* sioopen gets compared to the d_open entry in struct cdevsw. d_open and
* other functions are declared in <sys/conf.h> with short types like dev_t
* in the prototype. Such declarations are broken because they vary with
* __P (significantly in theory - the compiler is allowed to push a short
* arg if it has seen the prototype; insignificantly in practice - gcc
* doesn't push short args and it would be slower on 386's to do so).
*
* Also, most of the device switch functions are still declared old-style
* so they take a Dev_t arg and shorten it to a dev_t. It would be simpler
* and faster if dev_t's were always promoted (to ints or whatever) as
* early as possible.
*
* Until <sys/conf.h> is fixed, we cast sioopen to the following `wrong' type
* when comparing it to the d_open entry just to avoid compiler warnings.
*/
typedef int (*bogus_open_t) __P((dev_t dev, int oflags, int devtype,
struct proc *p));
int sioread __P((Dev_t dev, struct uio *uio, int ioflag));
void siostop __P((struct tty *tp, int rw));
int siowrite __P((Dev_t dev, struct uio *uio, int ioflag));
void softsio0 __P((void));
void softsio1 __P((void));
void softsio2 __P((void));
void softsio3 __P((void));
void softsio4 __P((void));
void softsio5 __P((void));
void softsio6 __P((void));
void softsio7 __P((void));
void softsio8 __P((void));
static int sioattach __P((struct isa_device *dev));
static void comflush __P((struct com_s *com));
static void comhardclose __P((struct com_s *com));
static void cominit __P((int unit, int rate));
static int commctl __P((struct com_s *com, int bits, int how));
static int comparam __P((struct tty *tp, struct termios *t));
static int sioprobe __P((struct isa_device *dev));
static void compoll __P((void));
static int comstart __P((struct tty *tp));
static void comwakeup __P((void));
/* table and macro for fast conversion from a unit number to its com struct */
static struct com_s *p_com_addr[NSIO];
#define com_addr(unit) (p_com_addr[unit])
static struct com_s com_structs[NSIO];
struct isa_driver siodriver = {
sioprobe, sioattach, "sio"
};
#ifdef COMCONSOLE
static int comconsole = COMCONSOLE;
#else
static int comconsole = -1;
#endif
static bool_t comconsinit;
static speed_t comdefaultrate = TTYDEF_SPEED;
static u_int com_events; /* input chars + weighted output completions */
static int commajor;
struct tty sio_tty[NSIO];
extern struct tty *constty;
extern u_int ipending; /* XXX */
extern int tk_nin; /* XXX */
extern int tk_rawcc; /* XXX */
#ifdef KGDB
#include "machine/remote-sl.h"
extern int kgdb_dev;
extern int kgdb_rate;
extern int kgdb_debug_init;
#endif
static struct speedtab comspeedtab[] = {
0, 0,
50, COMBRD(50),
75, COMBRD(75),
110, COMBRD(110),
134, COMBRD(134),
150, COMBRD(150),
200, COMBRD(200),
300, COMBRD(300),
600, COMBRD(600),
1200, COMBRD(1200),
1800, COMBRD(1800),
2400, COMBRD(2400),
4800, COMBRD(4800),
9600, COMBRD(9600),
19200, COMBRD(19200),
38400, COMBRD(38400),
57600, COMBRD(57600),
115200, COMBRD(115200),
-1, -1
};
/* XXX - configure this list */
static Port_t likely_com_ports[] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8, };
static int
sioprobe(dev)
struct isa_device *dev;
{
static bool_t already_init;
Port_t *com_ptr;
Port_t iobase;
int result;
if (!already_init) {
/*
* Turn off MCR_IENABLE for all likely serial ports. An unused
* port with its MCR_IENABLE gate open will inhibit interrupts
* from any used port that shares the interrupt vector.
*/
for (com_ptr = likely_com_ports;
com_ptr < &likely_com_ports[sizeof likely_com_ports
/ sizeof likely_com_ports[0]];
++com_ptr)
outb(*com_ptr + com_mcr, 0);
already_init = TRUE;
}
iobase = dev->id_iobase;
result = 1;
/*
* We don't want to get actual interrupts, just masked ones.
* Interrupts from this line should already be masked in the ICU,
* but mask them in the processor as well in case there are some
* (misconfigured) shared interrupts.
*/
disable_intr();
/*
* Enable output interrupts (only) and check the following:
* o the CFCR, IER and MCR in UART hold the values written to them
* (the values happen to be all distinct - this is good for
* avoiding false positive tests from bus echoes).
* o an output interrupt is generated and its vector is correct.
* o the interrupt goes away when the IIR in the UART is read.
*/
outb(iobase + com_cfcr, CFCR_8BITS); /* ensure IER is addressed */
outb(iobase + com_mcr, MCR_IENABLE); /* open gate early */
outb(iobase + com_ier, 0); /* ensure edge on next intr */
outb(iobase + com_ier, IER_ETXRDY); /* generate interrupt */
if ( inb(iobase + com_cfcr) != CFCR_8BITS
|| inb(iobase + com_ier) != IER_ETXRDY
|| inb(iobase + com_mcr) != MCR_IENABLE
|| !isa_irq_pending(dev)
|| (inb(iobase + com_iir) & IIR_IMASK) != IIR_TXRDY
|| isa_irq_pending(dev)
|| (inb(iobase + com_iir) & IIR_IMASK) != IIR_NOPEND)
result = 0;
/*
* Turn off all device interrupts and check that they go off properly.
* Leave MCR_IENABLE set. It gates the OUT2 output of the UART to
* the ICU input. Closing the gate would give a floating ICU input
* (unless there is another device driving at) and spurious interrupts.
* (On the system that this was first tested on, the input floats high
* and gives a (masked) interrupt as soon as the gate is closed.)
*/
outb(iobase + com_ier, 0);
outb(iobase + com_mcr, MCR_IENABLE); /* dummy to avoid bus echo */
if ( inb(iobase + com_ier) != 0
|| isa_irq_pending(dev)
|| (inb(iobase + com_iir) & IIR_IMASK) != IIR_NOPEND)
result = 0;
enable_intr();
return (result);
}
static int /* XXX - should be void */
sioattach(isdp)
struct isa_device *isdp;
{
struct com_s *com;
static bool_t comwakeup_started = FALSE;
Port_t iobase;
int s;
u_char scr;
u_char scr1;
u_char scr2;
int unit;
iobase = isdp->id_iobase;
unit = isdp->id_unit;
if (unit == comconsole)
DELAY(1000); /* XXX */
s = spltty();
/*
* sioprobe() has initialized the device registers as follows:
* o cfcr = CFCR_8BITS.
* It is most important that CFCR_DLAB is off, so that the
* data port is not hidden when we enable interrupts.
* o ier = 0.
* Interrupts are only enabled when the line is open.
* o mcr = MCR_IENABLE.
* Keeping MCR_DTR and MCR_RTS off might stop the external
* device from sending before we are ready.
*/
com = &com_structs[unit];
com->cfcr_image = CFCR_8BITS;
com->mcr_image = MCR_IENABLE;
#if 0
com->softDCD = TRUE;
#endif
com->iptr = com->ibuf = com->ibuf1;
com->ibufend = com->ibuf1 + RS_IBUFSIZE;
com->ihighwater = com->ibuf1 + RS_IHIGHWATER;
com->iobase = iobase;
com->data_port = iobase + com_data;
com->int_id_port = iobase + com_iir;
com->modem_ctl_port = iobase + com_mcr;
com->line_status_port = iobase + com_lsr;
com->modem_status_port = iobase + com_msr;
com->tp = &sio_tty[unit];
#ifdef COM_BIDIR
/*
* if bidirectional ports possible, clear the bidir port info;
*/
com->bidir = FALSE;
com->active = FALSE;
com->active_in = com->active_out = FALSE;
#endif /* COM_BIDIR */
/* attempt to determine UART type */
scr = inb(iobase + com_scr);
outb(iobase + com_scr, 0xa5);
scr1 = inb(iobase + com_scr);
outb(iobase + com_scr, 0x5a);
scr2 = inb(iobase + com_scr);
outb(iobase + com_scr, scr);
if (scr1 != 0xa5 || scr2 != 0x5a)
printf(" <8250>");
else {
outb(iobase + com_fifo, FIFO_ENABLE | FIFO_TRIGGER_14);
DELAY(100);
switch (inb(iobase + com_iir) & IIR_FIFO_MASK) {
case FIFO_TRIGGER_1:
printf(" <16450>");
break;
case FIFO_TRIGGER_4:
printf(" <16450?>");
break;
case FIFO_TRIGGER_8:
printf(" <16550?>");
break;
case FIFO_TRIGGER_14:
com->hasfifo = TRUE;
printf(" <16550A>");
break;
}
outb(iobase + com_fifo, 0);
}
#ifdef COM_MULTIPORT
if (COM_ISMULTIPORT(isdp)) {
struct isa_device *masterdev;
com->multiport = TRUE;
printf(" (multiport)");
/* set the master's common-interrupt-enable reg.,
* as appropriate. YYY See your manual
*/
/* enable only common interrupt for port */
outb(iobase + com_mcr, 0);
masterdev = find_isadev(isa_devtab_tty, &siodriver,
COM_MPMASTER(isdp));
outb(masterdev->id_iobase+com_scr, 0x80);
}
else
com->multiport = FALSE;
#endif /* COM_MULTIPORT */
#ifdef KGDB
if (kgdb_dev == makedev(commajor, unit)) {
if (comconsole == unit)
kgdb_dev = -1; /* can't debug over console port */
else {
cominit(unit, kgdb_rate);
if (kgdb_debug_init) {
/*
* Print prefix of device name,
* let kgdb_connect print the rest.
*/
printf("com%d: ", unit);
kgdb_connect(1);
}
else
printf("com%d: kgdb enabled\n", unit);
}
}
#endif
/*
* Need to reset baud rate, etc. of next print so reset comconsinit.
* Also make sure console is always "hardwired"
*/
if (unit == comconsole) {
comconsinit = FALSE;
com->softDCD = TRUE;
}
com_addr(unit) = com;
splx(s);
if (!comwakeup_started) {
comwakeup();
comwakeup_started = TRUE;
}
return (1);
}
/* ARGSUSED */
int
sioopen(dev, flag, mode, p)
dev_t dev;
int flag;
int mode;
struct proc *p;
{
struct com_s *com;
int error = 0;
Port_t iobase;
int s;
struct tty *tp;
int unit = UNIT(dev);
#ifdef COM_BIDIR
bool_t callout = CALLOUT(dev);
#endif /* COM_BIDIR */
if ((u_int) unit >= NSIO || (com = com_addr(unit)) == NULL)
return (ENXIO);
#ifdef COM_BIDIR
/* if it's a callout device, and bidir not possible on that dev, die */
if (callout && !(com->bidir))
return (ENXIO);
#endif /* COM_BIDIR */
tp = com->tp;
s = spltty();
#ifdef COM_BIDIR
bidir_open_top:
/* if it's bidirectional, we've gotta deal with it... */
if (com->bidir) {
if (callout) {
if (com->active_in) {
/* it's busy. die */
splx(s);
return (EBUSY);
} else {
/* it's ours. lock it down, and set it up */
com->active_out = TRUE;
com->softDCD = TRUE;
}
} else {
if (com->active_out) {
/* it's busy, outgoing. wait, if possible */
if (flag & O_NONBLOCK) {
/* can't wait; bail */
splx(s);
return (EBUSY);
} else {
/* wait for it... */
error = tsleep(&com->active_out,
TTIPRI|PCATCH,
"comoth",
0);
/* if there was an error, take off. */
if (error != 0) {
splx(s);
return (error);
}
/* else take it from the top */
goto bidir_open_top;
}
} else if (com->last_modem_status & MSR_DCD) {
/* there's a carrier on the line; we win */
com->active_in = TRUE;
com->softDCD = FALSE;
} else {
/* there is no carrier on the line */
if (flag & O_NONBLOCK) {
/* can't wait; let it open */
com->active_in = TRUE;
com->softDCD = FALSE;
} else {
/* put DTR & RTS up */
/* NOTE: cgd'sdriver used the ier register
* to enable/disable interrupts. This one
* uses both ier and IENABLE in the mcr.
*/
(void) commctl(com, MCR_DTR | MCR_RTS, DMSET);
outb(com->iobase + com_ier, IER_EMSC);
/* wait for it... */
error = tsleep(&com->active_in,
TTIPRI|PCATCH,
"comdcd",
0);
/* if not active, turn DTR & RTS off */
if (!com->active)
(void) commctl(com, MCR_DTR | MCR_RTS, DMBIC);
/* if there was an error, take off. */
if (error != 0) {
splx(s);
return (error);
}
/* else take it from the top */
goto bidir_open_top;
}
}
}
}
com->active = TRUE;
#endif /* COM_BIDIR */
tp->t_oproc = comstart;
tp->t_param = comparam;
tp->t_dev = dev;
if (!(tp->t_state & TS_ISOPEN)) {
tp->t_state |= TS_WOPEN;
ttychars(tp);
if (tp->t_ispeed == 0) {
/*
* We no longer use the flags from <sys/ttydefaults.h>
* since those are only relevant for logins. It's
* important to have echo off initially so that the
* line doesn't start blathering before the echo flag
* can be turned off. It's useful to have clocal on
* initially so that "stty changed-defaults </dev/comx"
* doesn't hang waiting for carrier.
*/
tp->t_iflag = 0;
tp->t_oflag = 0;
tp->t_cflag = CREAD | CS8 | CLOCAL;
tp->t_lflag = 0;
tp->t_ispeed = tp->t_ospeed = comdefaultrate;
}
(void) commctl(com, MCR_DTR | MCR_RTS, DMSET);
error = comparam(tp, &tp->t_termios);
if (error != 0)
goto out;
ttsetwater(tp);
iobase = com->iobase;
disable_intr();
if (com->hasfifo)
/* (re)enable and drain FIFO */
outb(iobase + com_fifo, FIFO_ENABLE | FIFO_TRIGGER_14
| FIFO_RCV_RST | FIFO_XMT_RST);
(void) inb(com->line_status_port);
(void) inb(com->data_port);
com->last_modem_status =
com->prev_modem_status = inb(com->modem_status_port);
outb(iobase + com_ier, IER_ERXRDY | IER_ETXRDY | IER_ERLS
| IER_EMSC);
enable_intr();
if (com->softDCD || com->prev_modem_status & MSR_DCD)
tp->t_state |= TS_CARR_ON;
}
else if (tp->t_state & TS_XCLUDE && p->p_ucred->cr_uid != 0) {
splx(s);
return (EBUSY);
}
while (!(flag & O_NONBLOCK) && !(tp->t_cflag & CLOCAL)
#ifdef COM_BIDIR
/* We went through a lot of trouble to open it,
* but it's certain we have a carrier now, so
* don't spend any time on it now.
*/
&& !(com->bidir)
#endif /* COM_BIDIR */
&& !(tp->t_state & TS_CARR_ON)) {
tp->t_state |= TS_WOPEN;
error = ttysleep(tp, (caddr_t)&tp->t_raw, TTIPRI | PCATCH,
ttopen, 0);
if (error != 0)
break;
}
out:
splx(s);
if (error == 0)
error = (*linesw[tp->t_line].l_open)(dev, tp);
#ifdef COM_BIDIR
/* wakeup sleepers */
wakeup((caddr_t) &com->active_in);
#endif /* COM_BIDIR */
/*
* XXX - the next step was once not done, so interrupts, DTR and RTS
* remainded hot if the process was killed while it was sleeping
* waiting for carrier. Now there is the opposite problem. If several
* processes are sleeping waiting for carrier on the same line and one
* is killed, interrupts are turned off so the other processes will
* never see the carrier rise.
*/
if (error != 0 && !(tp->t_state & TS_ISOPEN))
{
comhardclose(com);
}
tp->t_state &= ~TS_WOPEN;
return (error);
}
/*ARGSUSED*/
int
sioclose(dev, flag, mode, p)
dev_t dev;
int flag;
int mode;
struct proc *p;
{
struct com_s *com;
struct tty *tp;
com = com_addr(UNIT(dev));
tp = com->tp;
(*linesw[tp->t_line].l_close)(tp, flag);
comhardclose(com);
ttyclose(tp);
return (0);
}
void
comhardclose(com)
struct com_s *com;
{
Port_t iobase;
int s;
struct tty *tp;
s = spltty();
iobase = com->iobase;
outb(iobase + com_cfcr, com->cfcr_image &= ~CFCR_SBREAK);
#ifdef KGDB
/* do not disable interrupts if debugging */
if (kgdb_dev != makedev(commajor, com - &com_structs[0]))
#endif
outb(iobase + com_ier, 0);
tp = com->tp;
if (tp->t_cflag & HUPCL || tp->t_state & TS_WOPEN
|| !(tp->t_state & TS_ISOPEN))
(void) commctl(com, 0, DMSET);
#ifdef COM_BIDIR
com->active = com->active_in = com->active_out = FALSE;
com->softDCD = FALSE;
/* wakeup sleepers who are waiting for out to finish */
wakeup((caddr_t) &com->active_out);
#endif /* COM_BIDIR */
splx(s);
}
int
sioread(dev, uio, flag)
dev_t dev;
struct uio *uio;
int flag;
{
struct tty *tp = com_addr(UNIT(dev))->tp;
return ((*linesw[tp->t_line].l_read)(tp, uio, flag));
}
int
siowrite(dev, uio, flag)
dev_t dev;
struct uio *uio;
int flag;
{
int unit = UNIT(dev);
struct tty *tp = com_addr(unit)->tp;
/*
* (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 == comconsole)
constty = NULL;
return ((*linesw[tp->t_line].l_write)(tp, uio, flag));
}
void
siointr(unit)
int unit;
{
struct com_s *com;
#ifndef COM_MULTIPORT
u_char line_status;
u_char modem_status;
u_char *ioptr;
u_char recv_data;
com = com_addr(unit);
#else /* COM_MULTIPORT */
int i;
bool_t donesomething;
do {
donesomething = FALSE;
for(i=0;i<NSIO;i++) {
com=com_addr(i);
if(com != NULL) {
/* XXX When siointr is called
* to start output, maybe
* it should be changed to a
* call to comintr1. Doesn't
* seem a good idea: interrupts
* are disabled all the time.
*/
enable_intr();
disable_intr();
donesomething = comintr1(com);
}
}
} while (donesomething);
return;
}
bool_t
comintr1(struct com_s *com)
{
u_char line_status;
u_char modem_status;
u_char *ioptr;
u_char recv_data;
bool_t donesomething;
donesomething = FALSE;
#endif /* COM_MULTIPORT */
while (TRUE) {
line_status = inb(com->line_status_port);
/* input event? (check first to help avoid overruns) */
while (line_status & LSR_RCV_MASK) {
/* break/unnattached error bits or real input? */
#ifdef COM_MULTIPORT
donesomething = TRUE;
#endif /* COM_MULTIPORT */
if (!(line_status & LSR_RXRDY))
recv_data = 0;
else
recv_data = inb(com->data_port);
++com->bytes_in;
#ifdef KGDB
/* trap into kgdb? (XXX - needs testing and optim) */
if (recv_data == FRAME_END
&& !(com->tp->t_state & TS_ISOPEN)
&& kgdb_dev == makedev(commajor, unit)) {
kgdb_connect(0);
continue;
}
#endif /* KGDB */
ioptr = com->iptr;
if (ioptr >= com->ibufend)
CE_RECORD(com, CE_INTERRUPT_BUF_OVERFLOW);
else {
++com_events;
ioptr[0] = recv_data;
ioptr[CE_INPUT_OFFSET] = line_status;
com->iptr = ++ioptr;
if (ioptr == com->ihighwater
&& com->state & CS_RTS_IFLOW)
outb(com->modem_ctl_port,
com->mcr_image &= ~MCR_RTS);
}
/*
* "& 0x7F" is to avoid the gcc-1.40 generating a slow
* jump from the top of the loop to here
*/
line_status = inb(com->line_status_port) & 0x7F;
}
/* modem status change? (always check before doing output) */
modem_status = inb(com->modem_status_port);
if (modem_status != com->last_modem_status) {
/*
* Schedule high level to handle DCD changes. Note
* that we don't use the delta bits anywhere. Some
* UARTs mess them up, and it's easy to remember the
* previous bits and calculate the delta.
*/
#ifdef COM_MULTIPORT
donesomething = TRUE;
#endif /* COM_MULTIPORT */
com->last_modem_status = modem_status;
if (!(com->state & CS_CHECKMSR)) {
com_events += LOTS_OF_EVENTS;
com->state |= CS_CHECKMSR;
schedsoftcom();
}
/* handle CTS change immediately for crisp flow ctl */
if (com->state & CS_CTS_OFLOW) {
if (modem_status & MSR_CTS)
com->state |= CS_ODEVREADY;
else
com->state &= ~CS_ODEVREADY;
}
}
/* output queued and everything ready? */
if (line_status & LSR_TXRDY
&& com->state >= (CS_ODEVREADY | CS_BUSY | CS_TTGO)) {
#ifdef COM_MULTIPORT
donesomething = TRUE;
#endif /* COM_MULTIPORT */
ioptr = com->optr;
outb(com->data_port, *ioptr);
++com->bytes_out;
com->optr = ++ioptr;
if (ioptr >= com->obufend) {
/* output just completed */
com_events += LOTS_OF_EVENTS;
com->state ^= (CS_ODONE | CS_BUSY);
schedsoftcom(); /* handle at high level ASAP */
}
}
/* finished? */
if ((inb(com->int_id_port) & IIR_IMASK) == IIR_NOPEND)
#ifdef COM_MULTIPORT
return (donesomething);
#else
return;
#endif /* COM_MULTIPORT */
}
}
int
sioioctl(dev, cmd, data, flag, p)
dev_t dev;
int cmd;
caddr_t data;
int flag;
struct proc *p;
{
struct com_s *com;
int error;
Port_t iobase;
int s;
struct tty *tp;
com = com_addr(UNIT(dev));
tp = com->tp;
error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag);
if (error >= 0)
return (error);
error = ttioctl(tp, cmd, data, flag);
if (error >= 0)
return (error);
iobase = com->iobase;
s = spltty();
switch (cmd) {
case TIOCSBRK:
outb(iobase + com_cfcr, com->cfcr_image |= CFCR_SBREAK);
break;
case TIOCCBRK:
outb(iobase + com_cfcr, com->cfcr_image &= ~CFCR_SBREAK);
break;
case TIOCSDTR:
(void) commctl(com, MCR_DTR | MCR_RTS, DMBIS);
break;
case TIOCCDTR:
(void) commctl(com, MCR_DTR | MCR_RTS, DMBIC);
break;
case TIOCMSET:
(void) commctl(com, *(int *)data, DMSET);
break;
case TIOCMBIS:
(void) commctl(com, *(int *)data, DMBIS);
break;
case TIOCMBIC:
(void) commctl(com, *(int *)data, DMBIC);
break;
case TIOCMGET:
*(int *)data = commctl(com, 0, DMGET);
break;
#ifdef COM_BIDIR
case TIOCMSBIDIR:
/* must be root to set bidir. capability */
if (p->p_ucred->cr_uid != 0)
return(EPERM);
/* if it's the console, can't do it */
if (UNIT(dev) == comconsole)
return(ENOTTY);
/* can't do the next, for obvious reasons...
* but there are problems to be looked at...
*/
/* if the port is active, don't do it */
/* if (com->active)
return(EBUSY); */
com->bidir = *(int *)data;
break;
case TIOCMGBIDIR:
*(int *)data = com->bidir;
break;
#endif /* COM_BIDIR */
default:
splx(s);
return (ENOTTY);
}
splx(s);
return (0);
}
/* cancel pending output */
static void
comflush(com)
struct com_s *com;
{
struct ringb *rbp;
disable_intr();
if (com->state & CS_ODONE)
com_events -= LOTS_OF_EVENTS;
com->state &= ~(CS_ODONE | CS_BUSY);
enable_intr();
rbp = &com->tp->t_out;
rbp->rb_hd += com->ocount;
rbp->rb_hd = RB_ROLLOVER(rbp, rbp->rb_hd);
com->ocount = 0;
com->tp->t_state &= ~TS_BUSY;
}
static void
compoll()
{
static bool_t awake = FALSE;
struct com_s *com;
int s;
int unit;
if (com_events == 0)
return;
disable_intr();
if (awake) {
enable_intr();
return;
}
awake = TRUE;
enable_intr();
s = spltty();
repeat:
for (unit = 0; unit < NSIO; ++unit) {
u_char *buf;
u_char *ibuf;
int incc;
struct tty *tp;
com = com_addr(unit);
if (com == NULL)
continue;
tp = com->tp;
/* switch the role of the low-level input buffers */
if (com->iptr == (ibuf = com->ibuf))
incc = 0;
else {
buf = ibuf;
disable_intr();
incc = com->iptr - buf;
com_events -= incc;
if (ibuf == com->ibuf1)
ibuf = com->ibuf2;
else
ibuf = com->ibuf1;
com->ibufend = ibuf + RS_IBUFSIZE;
com->ihighwater = ibuf + RS_IHIGHWATER;
com->iptr = ibuf;
/*
* There is now room for another low-level buffer full
* of input, so enable RTS if it is now disabled and
* there is room in the high-level buffer.
*/
if (!(com->mcr_image & MCR_RTS)
&& !(tp->t_state & TS_RTSBLOCK))
outb(com->modem_ctl_port,
com->mcr_image |= MCR_RTS);
enable_intr();
com->ibuf = ibuf;
}
if (com->state & CS_CHECKMSR) {
u_char delta_modem_status;
disable_intr();
delta_modem_status = com->last_modem_status
^ com->prev_modem_status;
com->prev_modem_status = com->last_modem_status;
com_events -= LOTS_OF_EVENTS;
com->state &= ~CS_CHECKMSR;
enable_intr();
if (delta_modem_status & MSR_DCD &&
unit != comconsole) {
#ifdef COM_BIDIR
if (com->prev_modem_status & MSR_DCD) {
(*linesw[tp->t_line].l_modem)(tp, 1);
com->softDCD = FALSE;
wakeup((caddr_t) &com->active_in);
}
#else
if (com->prev_modem_status & MSR_DCD)
(*linesw[tp->t_line].l_modem)(tp, 1);
#endif /* COM_BIDIR */
else if ((*linesw[tp->t_line].l_modem)(tp, 0)
== 0) {
disable_intr();
outb(com->modem_ctl_port,
com->mcr_image
&= ~(MCR_DTR | MCR_RTS));
enable_intr();
}
}
}
/* XXX */
if (TRUE) {
u_int delta;
u_int delta_error_counts[CE_NTYPES];
int errnum;
u_long total;
disable_intr();
bcopy(com->delta_error_counts, delta_error_counts,
sizeof delta_error_counts);
bzero(com->delta_error_counts,
sizeof delta_error_counts);
enable_intr();
for (errnum = 0; errnum < CE_NTYPES; ++errnum) {
delta = delta_error_counts[errnum];
if (delta != 0) {
total =
com->error_counts[errnum] += delta;
log(LOG_WARNING,
"com%d: %u more %s%s (total %lu)\n",
unit, delta, error_desc[errnum],
delta == 1 ? "" : "s", total);
}
}
}
if (com->state & CS_ODONE) {
comflush(com);
/* XXX - why isn't the table used for t_line == 0? */
if (tp->t_line != 0)
(*linesw[tp->t_line].l_start)(tp);
else
comstart(tp);
}
if (incc <= 0 || !(tp->t_state & TS_ISOPEN))
continue;
if (com->state & CS_RTS_IFLOW
&& RB_LEN(&tp->t_raw) + incc >= RB_I_HIGH_WATER
&& !(tp->t_state & TS_RTSBLOCK)
/*
* XXX - need RTS flow control for all line disciplines.
* Only have it in standard one now.
*/
&& linesw[tp->t_line].l_rint == ttyinput) {
tp->t_state |= TS_RTSBLOCK;
ttstart(tp);
}
/*
* Avoid the grotesquely inefficient lineswitch routine
* (ttyinput) in "raw" mode. It usually takes about 450
* instructions (that's without canonical processing or echo!).
* slinput is reasonably fast (usually 40 instructions plus
* call overhead).
*/
if (!(tp->t_iflag & (ICRNL | IGNCR | IMAXBEL | INLCR | ISTRIP
| IXOFF | IXON))
&& !(tp->t_lflag & (ECHO | ECHONL | ICANON | IEXTEN | ISIG
| PENDIN))
&& !(tp->t_state & (TS_CNTTB | TS_LNCH))
&& linesw[tp->t_line].l_rint == ttyinput) {
tk_nin += incc;
tk_rawcc += incc;
tp->t_rawcc += incc;
com->delta_error_counts[CE_TTY_BUF_OVERFLOW]
+= incc - rb_write(&tp->t_raw, (char *) buf,
incc);
ttwakeup(tp);
if (tp->t_state & TS_TTSTOP
&& (tp->t_iflag & IXANY
|| tp->t_cc[VSTART] == tp->t_cc[VSTOP])) {
tp->t_state &= ~TS_TTSTOP;
tp->t_lflag &= ~FLUSHO;
ttstart(tp);
}
}
else {
do {
u_char line_status;
int recv_data;
line_status = (u_char) buf[CE_INPUT_OFFSET];
recv_data = (u_char) *buf++;
if (line_status
& (LSR_BI | LSR_FE | LSR_OE | LSR_PE)) {
if (line_status & LSR_BI)
recv_data |= TTY_BI;
if (line_status & LSR_FE)
recv_data |= TTY_FE;
if (line_status & LSR_OE)
recv_data |= TTY_OE;
if (line_status & LSR_PE)
recv_data |= TTY_PE;
}
(*linesw[tp->t_line].l_rint)(recv_data, tp);
} while (--incc > 0);
}
if (com_events == 0)
break;
}
if (com_events >= LOTS_OF_EVENTS)
goto repeat;
splx(s);
awake = FALSE;
}
static int
comparam(tp, t)
struct tty *tp;
struct termios *t;
{
u_int cfcr;
int cflag;
struct com_s *com;
int divisor;
int error;
Port_t iobase;
int s;
int unit;
/* check requested parameters */
divisor = ttspeedtab(t->c_ospeed, comspeedtab);
if (divisor < 0 || t->c_ispeed != 0 && t->c_ispeed != t->c_ospeed)
return (EINVAL);
/* parameters are OK, convert them to the com struct and the device */
unit = UNIT(tp->t_dev);
com = com_addr(unit);
iobase = com->iobase;
s = spltty();
if (divisor == 0) {
(void) commctl(com, 0, DMSET); /* hang up line */
splx(s);
return (0);
}
cflag = t->c_cflag;
switch (cflag & CSIZE) {
case CS5:
cfcr = CFCR_5BITS;
break;
case CS6:
cfcr = CFCR_6BITS;
break;
case CS7:
cfcr = CFCR_7BITS;
break;
default:
cfcr = CFCR_8BITS;
break;
}
if (cflag & PARENB) {
cfcr |= CFCR_PENAB;
if (!(cflag & PARODD))
cfcr |= CFCR_PEVEN;
}
if (cflag & CSTOPB)
cfcr |= CFCR_STOPB;
/*
* Some UARTs lock up if the divisor latch registers are selected
* while the UART is doing output (they refuse to transmit anything
* more until given a hard reset). Fix this by stopping filling
* the device buffers and waiting for them to drain. Reading the
* line status port outside of siointr() might lose some receiver
* error bits, but that is acceptable here.
*/
disable_intr();
com->state &= ~CS_TTGO;
enable_intr();
while ((inb(com->line_status_port) & (LSR_TSRE | LSR_TXRDY))
!= (LSR_TSRE | LSR_TXRDY)) {
error = ttysleep(tp, (caddr_t)&tp->t_raw, TTIPRI | PCATCH,
"comparam", 1);
if (error != 0 && error != EAGAIN) {
if (!(tp->t_state & TS_TTSTOP)) {
disable_intr();
com->state |= CS_TTGO;
enable_intr();
}
splx(s);
return (error);
}
}
disable_intr(); /* very important while com_data is hidden */
outb(iobase + com_cfcr, cfcr | CFCR_DLAB);
outb(iobase + com_dlbl, divisor & 0xFF);
outb(iobase + com_dlbh, (u_int) divisor >> 8);
outb(iobase + com_cfcr, com->cfcr_image = cfcr);
if (!(tp->t_state & TS_TTSTOP))
com->state |= CS_TTGO;
if (cflag & CRTS_IFLOW)
com->state |= CS_RTS_IFLOW; /* XXX - secondary changes? */
else
com->state &= ~CS_RTS_IFLOW;
/*
* Set up state to handle output flow control.
* XXX - worth handling MDMBUF (DCD) flow control at the lowest level?
* Now has 16+ msec latency, while CTS flow has 50- usec latency.
* Note that DCD flow control stupidly uses the same state flag
* (TS_TTSTOP) as XON/XOFF flow control.
*/
com->state &= ~CS_CTS_OFLOW;
com->state |= CS_ODEVREADY;
if (cflag & CCTS_OFLOW) {
com->state |= CS_CTS_OFLOW;
if (!(com->prev_modem_status & MSR_CTS))
com->state &= ~CS_ODEVREADY;
}
enable_intr();
siointr(unit); /* recover from fiddling with CS_TTGO */
splx(s);
return (0);
}
static int /* XXX - should be void */
comstart(tp)
struct tty *tp;
{
struct com_s *com;
int s;
int unit;
unit = UNIT(tp->t_dev);
com = com_addr(unit);
s = spltty();
disable_intr();
if (tp->t_state & TS_TTSTOP)
com->state &= ~CS_TTGO;
else
com->state |= CS_TTGO;
if (tp->t_state & TS_RTSBLOCK) {
if (com->mcr_image & MCR_RTS && com->state & CS_RTS_IFLOW)
outb(com->modem_ctl_port, com->mcr_image &= ~MCR_RTS);
}
else {
if (!(com->mcr_image & MCR_RTS) && com->iptr < com->ihighwater)
outb(com->modem_ctl_port, com->mcr_image |= MCR_RTS);
}
enable_intr();
if (tp->t_state & (TS_TIMEOUT | TS_TTSTOP))
goto out;
if (RB_LEN(&tp->t_out) <= tp->t_lowat) {
if (tp->t_state & TS_ASLEEP) {
tp->t_state &= ~TS_ASLEEP;
wakeup((caddr_t)&tp->t_out);
}
if (tp->t_wsel) {
selwakeup(tp->t_wsel, tp->t_state & TS_WCOLL);
tp->t_wsel = 0;
tp->t_state &= ~TS_WCOLL;
}
}
if (com->ocount != 0) {
disable_intr();
siointr(unit);
enable_intr();
}
else if (RB_LEN(&tp->t_out) != 0) {
tp->t_state |= TS_BUSY;
com->ocount = RB_CONTIGGET(&tp->t_out);
disable_intr();
com->obufend = (com->optr = (u_char *) tp->t_out.rb_hd)
+ com->ocount;
com->state |= CS_BUSY;
siointr(unit); /* fake interrupt to start output */
enable_intr();
}
out:
splx(s);
return (1);
}
void
siostop(tp, rw)
struct tty *tp;
int rw;
{
struct com_s *com;
com = com_addr(UNIT(tp->t_dev));
if (rw & FWRITE)
comflush(com);
disable_intr();
if (tp->t_state & TS_TTSTOP)
com->state &= ~CS_TTGO;
else
com->state |= CS_TTGO;
enable_intr();
}
static int
commctl(com, bits, how)
struct com_s *com;
int bits;
int how;
{
disable_intr();
switch (how) {
case DMSET:
#ifdef COM_MULTIPORT
/* YYY maybe your card doesn't want IENABLE to be reset? */
if(com->multiport)
outb(com->modem_ctl_port,
com->mcr_image = bits);
else
#endif /* COM_MULTIPORT */
outb(com->modem_ctl_port,
com->mcr_image = bits | MCR_IENABLE);
break;
case DMBIS:
outb(com->modem_ctl_port, com->mcr_image |= bits);
break;
case DMBIC:
#ifdef COM_MULTIPORT
/* YYY maybe your card doesn't want IENABLE to be reset? */
if(com->multiport)
outb(com->modem_ctl_port,
com->mcr_image &= ~(bits));
else
#endif /* COM_MULTIPORT */
outb(com->modem_ctl_port,
com->mcr_image &= ~(bits & ~MCR_IENABLE));
break;
case DMGET:
bits = com->prev_modem_status;
break;
}
enable_intr();
return (bits);
}
static void
comwakeup()
{
struct com_s *com;
int unit;
timeout((timeout_func_t) comwakeup, (caddr_t) NULL, 1);
if (com_events != 0)
/* schedule compoll() to run when the cpl allows */
schedsoftcom();
/* recover from lost output interrupts */
for (unit = 0; unit < NSIO; ++unit) {
com = com_addr(unit);
if (com != NULL && com->state >= (CS_BUSY | CS_TTGO)) {
disable_intr();
siointr(unit);
enable_intr();
}
}
}
void
softsio0() { compoll(); }
void
softsio1() { compoll(); }
void
softsio2() { compoll(); }
void
softsio3() { compoll(); }
void
softsio4() { compoll(); }
void
softsio5() { compoll(); }
void
softsio6() { compoll(); }
void
softsio7() { compoll(); }
void
softsio8() { compoll(); }
/*
* Following are all routines needed for COM to act as console
* XXX - not tested in this version
* XXX - check that the corresponding serial interrupts are never enabled
*/
#include "i386/i386/cons.h"
void
siocnprobe(cp)
struct consdev *cp;
{
int unit;
/* locate the major number */
for (commajor = 0; commajor < nchrdev; commajor++)
if (cdevsw[commajor].d_open == (bogus_open_t) sioopen)
break;
/* XXX: ick */
unit = CONUNIT;
com_addr(unit) = &com_structs[unit];
com_addr(unit)->iobase = CONADDR;
/* make sure hardware exists? XXX */
/* initialize required fields */
cp->cn_dev = makedev(commajor, unit);
cp->cn_tp = &sio_tty[unit];
#ifdef COMCONSOLE
cp->cn_pri = CN_REMOTE; /* Force a serial port console */
#else
cp->cn_pri = CN_NORMAL;
#endif
}
void
siocninit(cp)
struct consdev *cp;
{
int unit;
unit = UNIT(cp->cn_dev);
cominit(unit, comdefaultrate);
comconsole = unit;
comconsinit = TRUE;
}
static void
cominit(unit, rate)
int unit;
int rate;
{
Port_t iobase;
int s;
iobase = com_addr(unit)->iobase;
s = splhigh();
outb(iobase + com_cfcr, CFCR_DLAB);
rate = ttspeedtab(comdefaultrate, comspeedtab);
outb(iobase + com_data, rate & 0xFF);
outb(iobase + com_ier, rate >> 8);
outb(iobase + com_cfcr, CFCR_8BITS);
/*
* XXX - fishy to enable interrupts and then poll.
* It shouldn't be necessary to ready the iir.
*/
outb(iobase + com_ier, IER_ERXRDY | IER_ETXRDY | IER_ERLS | IER_EMSC);
outb(iobase + com_fifo,
FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_14);
(void) inb(iobase + com_iir);
splx(s);
}
int
siocngetc(dev)
dev_t dev;
{
int c;
Port_t iobase;
int s;
iobase = com_addr(UNIT(dev))->iobase;
s = splhigh();
while (!(inb(iobase + com_lsr) & LSR_RXRDY))
;
c = inb(iobase + com_data);
(void) inb(iobase + com_iir);
splx(s);
return (c);
}
void
siocnputc(dev, c)
dev_t dev;
int c;
{
Port_t iobase;
int s;
int timo;
iobase = com_addr(UNIT(dev))->iobase;
s = splhigh();
#ifdef KGDB
if (dev != kgdb_dev)
#endif
if (!comconsinit) {
(void) cominit(UNIT(dev), comdefaultrate);
comconsinit = TRUE;
}
/* wait for any pending transmission to finish */
timo = 50000;
while (!(inb(iobase + com_lsr) & LSR_TXRDY) && --timo)
;
outb(iobase + com_data, c);
/* wait for this transmission to complete */
timo = 1500000;
while (!(inb(iobase + com_lsr) & LSR_TXRDY) && --timo)
;
/* clear any interrupts generated by this transmission */
(void) inb(iobase + com_iir);
splx(s);
}
/*
* 10 Feb 93 Jordan K. Hubbard Added select code
* 27 May 93 Rodney W. Grimes Stole the select code from com.c.pl5
*/
int
sioselect(dev, rw, p)
dev_t dev;
int rw;
struct proc *p;
{
register struct tty *tp = &sio_tty[UNIT(dev)];
int nread;
int s = spltty();
struct proc *selp;
switch (rw) {
case FREAD:
nread = ttnread(tp);
if (nread > 0 ||
((tp->t_cflag&CLOCAL) == 0 && (tp->t_state&TS_CARR_ON) == 0))
goto win;
if (tp->t_rsel && (selp = pfind(tp->t_rsel)) && selp->p_wchan == (caddr_t)&selwait)
tp->t_state |= TS_RCOLL;
else
tp->t_rsel = p->p_pid;
break;
case FWRITE:
if (RB_LEN(&tp->t_out) <= tp->t_lowat)
goto win;
if (tp->t_wsel && (selp = pfind(tp->t_wsel)) && selp->p_wchan == (caddr_t)&selwait)
tp->t_state |= TS_WCOLL;
else
tp->t_wsel = p->p_pid;
break;
}
splx(s);
return (0);
win:
splx(s);
return (1);
}
#endif /* NSIO > 0 */
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.