freebsd-nq/sys/dev/uart/uart_tty.c
Andriy Gapon 9976156f12 kern cons: introduce infrastructure for console grabbing by kernel
At the moment grab and ungrab methods of all console drivers are no-ops.

Current intended meaning of the calls is that the kernel takes control of
console input.  In the future the semantics may be extended to mean that
the calling thread takes full ownership of the console (e.g. console
output from other threads could be suspended).

Inspired by:	bde
MFC after:	2 months
2011-12-17 15:08:43 +00:00

409 lines
9.1 KiB
C

/*-
* Copyright (c) 2003 Marcel Moolenaar
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/cons.h>
#include <sys/fcntl.h>
#include <sys/interrupt.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/reboot.h>
#include <machine/bus.h>
#include <sys/rman.h>
#include <sys/tty.h>
#include <machine/resource.h>
#include <machine/stdarg.h>
#include <dev/uart/uart.h>
#include <dev/uart/uart_bus.h>
#include <dev/uart/uart_cpu.h>
#include "uart_if.h"
static cn_probe_t uart_cnprobe;
static cn_init_t uart_cninit;
static cn_term_t uart_cnterm;
static cn_getc_t uart_cngetc;
static cn_putc_t uart_cnputc;
static cn_grab_t uart_cngrab;
static cn_ungrab_t uart_cnungrab;
CONSOLE_DRIVER(uart);
static struct uart_devinfo uart_console;
static void
uart_cnprobe(struct consdev *cp)
{
cp->cn_pri = CN_DEAD;
KASSERT(uart_console.cookie == NULL, ("foo"));
if (uart_cpu_getdev(UART_DEV_CONSOLE, &uart_console))
return;
if (uart_probe(&uart_console))
return;
strlcpy(cp->cn_name, uart_driver_name, sizeof(cp->cn_name));
cp->cn_pri = (boothowto & RB_SERIAL) ? CN_REMOTE : CN_NORMAL;
cp->cn_arg = &uart_console;
}
static void
uart_cninit(struct consdev *cp)
{
struct uart_devinfo *di;
/*
* Yedi trick: we need to be able to define cn_dev before we go
* single- or multi-user. The problem is that we don't know at
* this time what the device will be. Hence, we need to link from
* the uart_devinfo to the consdev that corresponds to it so that
* we can define cn_dev in uart_bus_attach() when we find the
* device during bus enumeration. That's when we'll know what the
* the unit number will be.
*/
di = cp->cn_arg;
KASSERT(di->cookie == NULL, ("foo"));
di->cookie = cp;
di->type = UART_DEV_CONSOLE;
uart_add_sysdev(di);
uart_init(di);
}
static void
uart_cnterm(struct consdev *cp)
{
uart_term(cp->cn_arg);
}
static void
uart_cngrab(struct consdev *cp)
{
}
static void
uart_cnungrab(struct consdev *cp)
{
}
static void
uart_cnputc(struct consdev *cp, int c)
{
uart_putc(cp->cn_arg, c);
}
static int
uart_cngetc(struct consdev *cp)
{
return (uart_poll(cp->cn_arg));
}
static int
uart_tty_open(struct tty *tp)
{
struct uart_softc *sc;
sc = tty_softc(tp);
if (sc == NULL || sc->sc_leaving)
return (ENXIO);
sc->sc_opened = 1;
return (0);
}
static void
uart_tty_close(struct tty *tp)
{
struct uart_softc *sc;
sc = tty_softc(tp);
if (sc == NULL || sc->sc_leaving || !sc->sc_opened)
return;
if (sc->sc_hwiflow)
UART_IOCTL(sc, UART_IOCTL_IFLOW, 0);
if (sc->sc_hwoflow)
UART_IOCTL(sc, UART_IOCTL_OFLOW, 0);
if (sc->sc_sysdev == NULL)
UART_SETSIG(sc, SER_DDTR | SER_DRTS);
wakeup(sc);
sc->sc_opened = 0;
return;
}
static void
uart_tty_outwakeup(struct tty *tp)
{
struct uart_softc *sc;
sc = tty_softc(tp);
if (sc == NULL || sc->sc_leaving)
return;
if (sc->sc_txbusy)
return;
/*
* Respect RTS/CTS (output) flow control if enabled and not already
* handled by hardware.
*/
if ((tp->t_termios.c_cflag & CCTS_OFLOW) && !sc->sc_hwoflow &&
!(sc->sc_hwsig & SER_CTS))
return;
sc->sc_txdatasz = ttydisc_getc(tp, sc->sc_txbuf, sc->sc_txfifosz);
if (sc->sc_txdatasz != 0)
UART_TRANSMIT(sc);
}
static void
uart_tty_inwakeup(struct tty *tp)
{
struct uart_softc *sc;
sc = tty_softc(tp);
if (sc == NULL || sc->sc_leaving)
return;
if (sc->sc_isquelch) {
if ((tp->t_termios.c_cflag & CRTS_IFLOW) && !sc->sc_hwiflow)
UART_SETSIG(sc, SER_DRTS|SER_RTS);
sc->sc_isquelch = 0;
uart_sched_softih(sc, SER_INT_RXREADY);
}
}
static int
uart_tty_ioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
{
struct uart_softc *sc;
sc = tty_softc(tp);
switch (cmd) {
case TIOCSBRK:
UART_IOCTL(sc, UART_IOCTL_BREAK, 1);
return (0);
case TIOCCBRK:
UART_IOCTL(sc, UART_IOCTL_BREAK, 0);
return (0);
default:
return pps_ioctl(cmd, data, &sc->sc_pps);
}
}
static int
uart_tty_param(struct tty *tp, struct termios *t)
{
struct uart_softc *sc;
int databits, parity, stopbits;
sc = tty_softc(tp);
if (sc == NULL || sc->sc_leaving)
return (ENODEV);
if (t->c_ispeed != t->c_ospeed && t->c_ospeed != 0)
return (EINVAL);
/* Fixate certain parameters for system devices. */
if (sc->sc_sysdev != NULL) {
t->c_ispeed = t->c_ospeed = sc->sc_sysdev->baudrate;
t->c_cflag |= CLOCAL;
t->c_cflag &= ~HUPCL;
}
if (t->c_ospeed == 0) {
UART_SETSIG(sc, SER_DDTR | SER_DRTS);
return (0);
}
switch (t->c_cflag & CSIZE) {
case CS5: databits = 5; break;
case CS6: databits = 6; break;
case CS7: databits = 7; break;
default: databits = 8; break;
}
stopbits = (t->c_cflag & CSTOPB) ? 2 : 1;
if (t->c_cflag & PARENB)
parity = (t->c_cflag & PARODD) ? UART_PARITY_ODD
: UART_PARITY_EVEN;
else
parity = UART_PARITY_NONE;
if (UART_PARAM(sc, t->c_ospeed, databits, stopbits, parity) != 0)
return (EINVAL);
UART_SETSIG(sc, SER_DDTR | SER_DTR);
/* Set input flow control state. */
if (!sc->sc_hwiflow) {
if ((t->c_cflag & CRTS_IFLOW) && sc->sc_isquelch)
UART_SETSIG(sc, SER_DRTS);
else
UART_SETSIG(sc, SER_DRTS | SER_RTS);
} else
UART_IOCTL(sc, UART_IOCTL_IFLOW, (t->c_cflag & CRTS_IFLOW));
/* Set output flow control state. */
if (sc->sc_hwoflow)
UART_IOCTL(sc, UART_IOCTL_OFLOW, (t->c_cflag & CCTS_OFLOW));
return (0);
}
static int
uart_tty_modem(struct tty *tp, int biton, int bitoff)
{
struct uart_softc *sc;
sc = tty_softc(tp);
if (biton != 0 || bitoff != 0)
UART_SETSIG(sc, SER_DELTA(bitoff|biton) | biton);
return (sc->sc_hwsig);
}
void
uart_tty_intr(void *arg)
{
struct uart_softc *sc = arg;
struct tty *tp;
int c, err = 0, pend, sig, xc;
if (sc->sc_leaving)
return;
pend = atomic_readandclear_32(&sc->sc_ttypend);
if (!(pend & SER_INT_MASK))
return;
tp = sc->sc_u.u_tty.tp;
tty_lock(tp);
if (pend & SER_INT_RXREADY) {
while (!uart_rx_empty(sc) && !sc->sc_isquelch) {
xc = uart_rx_peek(sc);
c = xc & 0xff;
if (xc & UART_STAT_FRAMERR)
err |= TRE_FRAMING;
if (xc & UART_STAT_OVERRUN)
err |= TRE_OVERRUN;
if (xc & UART_STAT_PARERR)
err |= TRE_PARITY;
if (ttydisc_rint(tp, c, err) != 0) {
sc->sc_isquelch = 1;
if ((tp->t_termios.c_cflag & CRTS_IFLOW) &&
!sc->sc_hwiflow)
UART_SETSIG(sc, SER_DRTS);
} else
uart_rx_next(sc);
}
}
if (pend & SER_INT_BREAK)
ttydisc_rint(tp, 0, TRE_BREAK);
if (pend & SER_INT_SIGCHG) {
sig = pend & SER_INT_SIGMASK;
if (sig & SER_DDCD)
ttydisc_modem(tp, sig & SER_DCD);
if (sig & SER_DCTS)
uart_tty_outwakeup(tp);
}
if (pend & SER_INT_TXIDLE)
uart_tty_outwakeup(tp);
ttydisc_rint_done(tp);
tty_unlock(tp);
}
static void
uart_tty_free(void *arg)
{
/*
* XXX: uart(4) could reuse the device unit number before it is
* being freed by the TTY layer. We should use this hook to free
* the device unit number, but unfortunately newbus does not
* seem to support such a construct.
*/
}
static struct ttydevsw uart_tty_class = {
.tsw_flags = TF_INITLOCK|TF_CALLOUT,
.tsw_open = uart_tty_open,
.tsw_close = uart_tty_close,
.tsw_outwakeup = uart_tty_outwakeup,
.tsw_inwakeup = uart_tty_inwakeup,
.tsw_ioctl = uart_tty_ioctl,
.tsw_param = uart_tty_param,
.tsw_modem = uart_tty_modem,
.tsw_free = uart_tty_free,
};
int
uart_tty_attach(struct uart_softc *sc)
{
struct tty *tp;
int unit;
sc->sc_u.u_tty.tp = tp = tty_alloc(&uart_tty_class, sc);
unit = device_get_unit(sc->sc_dev);
if (sc->sc_sysdev != NULL && sc->sc_sysdev->type == UART_DEV_CONSOLE) {
sprintf(((struct consdev *)sc->sc_sysdev->cookie)->cn_name,
"ttyu%r", unit);
tty_init_console(tp, 0);
}
swi_add(&tty_intr_event, uart_driver_name, uart_tty_intr, sc, SWI_TTY,
INTR_TYPE_TTY, &sc->sc_softih);
tty_makedev(tp, NULL, "u%r", unit);
return (0);
}
int
uart_tty_detach(struct uart_softc *sc)
{
struct tty *tp;
tp = sc->sc_u.u_tty.tp;
tty_lock(tp);
swi_remove(sc->sc_softih);
tty_rel_gone(tp);
return (0);
}