/*-
* Copyright (c) 1998, 1999, 2004, 2008 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Charles M. Hannum.
*
* 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.
*/
/*
* 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. 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.
*
* @(#)com.c 7.5 (Berkeley) 5/16/91
*/
/*
* COM driver, uses National Semiconductor NS16450/NS16550AF UART
* Supports automatic hardware flow control on StarTech ST16C650A UART
*
* Lock order:
* ttylock (IPL_VM)
* -> sc->sc_lock (IPL_HIGH)
* -> timecounter_lock (IPL_HIGH)
*/
/* The COM16650 option was renamed to COM_16650. */
#ifdef COM16650
#error Obsolete COM16650 option; use COM_16650 instead.
#endif
/*
* Override cnmagic(9) macro before including <sys/systm.h>.
* We need to know if cn_check_magic triggered debugger, so set a flag.
* Callers of cn_check_magic must declare int cn_trapped = 0;
* XXX: this is *ugly*!
*/
#define cn_trap() \
do { \
console_debugger(); \
cn_trapped = 1; \
(void)cn_trapped; \
} while (/* CONSTCOND */ 0)
/*
* Make this an option variable one can patch.
* But be warned: this must be a power of 2!
*/
u_int com_rbuf_size = COM_RING_SIZE;
/* Stop input when 3/4 of the ring is full; restart when only 1/4 is full. */
u_int com_rbuf_hiwat = (COM_RING_SIZE * 1) / 4;
u_int com_rbuf_lowat = (COM_RING_SIZE * 3) / 4;
static int comconsattached;
static struct cnm_state com_cnm_state;
#ifdef KGDB
#include <sys/kgdb.h>
static struct com_regs comkgdbregs;
static int com_kgdb_attached;
/*
* com_init_regs --
* Driver front-ends use this to initialize our register map
* in the standard fashion. They may then tailor the map to
* their own particular requirements.
*/
void
com_init_regs(struct com_regs *regs, bus_space_tag_t st, bus_space_handle_t sh,
bus_addr_t addr)
{
/*
* com_init_regs_stride --
* Convenience function for front-ends that have a stride between
* registers.
*/
void
com_init_regs_stride(struct com_regs *regs, bus_space_tag_t st,
bus_space_handle_t sh, bus_addr_t addr, u_int regshift)
{
com_init_regs(regs, st, sh, addr);
for (size_t i = 0; i < __arraycount(regs->cr_map); i++) {
regs->cr_map[i] <<= regshift;
}
regs->cr_nports <<= regshift;
}
/*
* com_init_regs_stride_width --
* Convenience function for front-ends that have a stride between
* registers and specific I/O width requirements.
*/
void
com_init_regs_stride_width(struct com_regs *regs, bus_space_tag_t st,
bus_space_handle_t sh, bus_addr_t addr,
u_int regshift, u_int width)
{
com_init_regs(regs, st, sh, addr);
for (size_t i = 0; i < __arraycount(regs->cr_map); i++) {
regs->cr_map[i] <<= regshift;
}
regs->cr_nports <<= regshift;
switch (width) {
case 1:
/* Already set by com_init_regs */
break;
case 4:
regs->cr_read = com_read_4;
regs->cr_write = com_write_4;
regs->cr_write_multi = com_write_multi_4;
break;
default:
panic("com: unsupported I/O width %d", width);
}
}
/*ARGSUSED*/
int
comspeed(long speed, long frequency, int type)
{
#define divrnd(n, q) (((n)*2/(q)+1)/2) /* divide and round off */
/* force access to id reg */
CSR_WRITE_1(regs, COM_REG_LCR, LCR_8BITS);
CSR_WRITE_1(regs, COM_REG_IIR, 0);
if ((CSR_READ_1(regs, COM_REG_LCR) != LCR_8BITS) ||
(CSR_READ_1(regs, COM_REG_IIR) & 0x38))
return (0);
return (1);
}
int
comprobe1(bus_space_tag_t iot, bus_space_handle_t ioh)
{
struct com_regs regs;
com_init_regs(®s, iot, ioh, 0/*XXX*/);
return com_probe_subr(®s);
}
/*
* No locking in this routine; it is only called during attach,
* or with the port already locked.
*/
static void
com_enable_debugport(struct com_softc *sc)
{
/* Turn on line break interrupt, set carrier. */
sc->sc_ier = IER_ERLS;
if (sc->sc_type == COM_TYPE_PXA2x0)
sc->sc_ier |= IER_EUART | IER_ERXTOUT;
if (sc->sc_type == COM_TYPE_INGENIC ||
sc->sc_type == COM_TYPE_TEGRA)
sc->sc_ier |= IER_ERXTOUT;
CSR_WRITE_1(&sc->sc_regs, COM_REG_IER, sc->sc_ier);
SET(sc->sc_mcr, MCR_DTR | MCR_RTS);
CSR_WRITE_1(&sc->sc_regs, COM_REG_MCR, sc->sc_mcr);
}
sc->sc_fifolen = 1;
/* look for a NS 16550AF UART with FIFOs */
if (sc->sc_type == COM_TYPE_INGENIC) {
CSR_WRITE_1(regsp, COM_REG_FIFO,
FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST |
FIFO_TRIGGER_14 | FIFO_UART_ON);
} else
CSR_WRITE_1(regsp, COM_REG_FIFO,
FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_14);
delay(100);
if (ISSET(CSR_READ_1(regsp, COM_REG_IIR), IIR_FIFO_MASK)
== IIR_FIFO_MASK)
if (ISSET(CSR_READ_1(regsp, COM_REG_FIFO), FIFO_TRIGGER_14)
== FIFO_TRIGGER_14) {
SET(sc->sc_hwflags, COM_HW_FIFO);
fifo_msg = "ns16550a";
sc->sc_fifolen = 16;
/*
* IIR changes into the EFR if LCR is set to LCR_EERS
* on 16650s. We also know IIR != 0 at this point.
* Write 0 into the EFR, and read it. If the result
* is 0, we have a 16650.
*
* Older 16650s were broken; the test to detect them
* is taken from the Linux driver. Apparently
* setting DLAB enable gives access to the EFR on
* these chips.
*/
if (sc->sc_type == COM_TYPE_16650) {
lcr = CSR_READ_1(regsp, COM_REG_LCR);
CSR_WRITE_1(regsp, COM_REG_LCR, LCR_EERS);
CSR_WRITE_1(regsp, COM_REG_EFR, 0);
if (CSR_READ_1(regsp, COM_REG_EFR) == 0) {
CSR_WRITE_1(regsp, COM_REG_LCR,
lcr | LCR_DLAB);
if (CSR_READ_1(regsp, COM_REG_EFR) == 0) {
CLR(sc->sc_hwflags, COM_HW_FIFO);
sc->sc_fifolen = 0;
} else {
SET(sc->sc_hwflags, COM_HW_FLOW);
sc->sc_fifolen = 32;
}
} else
sc->sc_fifolen = 16;
/*
* TL16C750 can enable 64byte FIFO, only when DLAB
* is 1. However, some 16750 may always enable. For
* example, restrictions according to DLAB in a data
* sheet for SC16C750 were not described.
* Please enable 'options COM_16650', supposing you
* use SC16C750. Probably 32 bytes of FIFO and HW FLOW
* should become effective.
*/
if (sc->sc_type == COM_TYPE_16750) {
uint8_t iir1, iir2;
uint8_t fcr = FIFO_ENABLE | FIFO_TRIGGER_14;
if (!ISSET(iir1, IIR_64B_FIFO) &&
ISSET(iir2, IIR_64B_FIFO)) {
/* It is TL16C750. */
sc->sc_fifolen = 64;
SET(sc->sc_hwflags, COM_HW_AFE);
} else
CSR_WRITE_1(regsp, COM_REG_FIFO, fcr);
if (sc->sc_fifolen == 64)
fifo_msg = "tl16c750";
else
fifo_msg = "ns16750";
}
} else
fifo_msg = "ns16550, broken fifo";
else
fifo_msg = "ns8250 or ns16450, no fifo";
CSR_WRITE_1(regsp, COM_REG_FIFO, 0);
fifodelay:
/*
* Some chips will clear down both Tx and Rx FIFOs when zero is
* written to com_fifo. If this chip is the console, writing zero
* results in some of the chip/FIFO description being lost, so delay
* printing it until now.
*/
delay(10);
if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) {
aprint_normal(": %s, %d-byte FIFO\n", fifo_msg, sc->sc_fifolen);
} else {
aprint_normal(": %s\n", fifo_msg);
}
if (ISSET(sc->sc_hwflags, COM_HW_TXFIFO_DISABLE)) {
sc->sc_fifolen = 1;
aprint_normal_dev(sc->sc_dev, "txfifo disabled\n");
}
#ifdef KGDB
/*
* Allow kgdb to "take over" this port. If this is
* not the console and is the kgdb device, it has
* exclusive use. If it's the console _and_ the
* kgdb device, it doesn't.
*/
if (bus_space_is_equal(regsp->cr_iot, comkgdbregs.cr_iot) &&
regsp->cr_iobase == comkgdbregs.cr_iobase) {
if (!ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
com_kgdb_attached = 1;
if (sc->sc_rbuf == NULL) {
/*
* Ring buffer allocation failed in the com_attach_subr,
* only the tty is allocated, and nothing else.
*/
tty_free(sc->sc_tty);
return 0;
}
/* Free the receive buffer. */
free(sc->sc_rbuf, M_DEVBUF);
/* Detach and free the tty. */
tty_detach(sc->sc_tty);
tty_free(sc->sc_tty);
/* Unhook the soft interrupt handler. */
softint_disestablish(sc->sc_si);
/* If we were asserting flow control, then deassert it. */
SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
com_hwiflow(sc);
/* Clear any break condition set with TIOCSBRK. */
com_break(sc, 0);
/*
* Hang up if necessary. Record when we hung up, so if we
* immediately open the port again, we will wait a bit until
* the other side has had time to notice that we hung up.
*/
if (ISSET(tp->t_cflag, HUPCL)) {
com_modem(sc, 0);
microuptime(&sc->sc_hup_pending);
sc->sc_hup_pending.tv_sec++;
}
/* Turn off interrupts. */
if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
sc->sc_ier = IER_ERLS; /* interrupt on line break */
if ((sc->sc_type == COM_TYPE_PXA2x0) ||
(sc->sc_type == COM_TYPE_INGENIC) ||
(sc->sc_type == COM_TYPE_TEGRA))
sc->sc_ier |= IER_ERXTOUT;
} else
sc->sc_ier = 0;
if (sc->sc_type == COM_TYPE_PXA2x0)
sc->sc_ier |= IER_EUART;
if (!device_is_active(sc->sc_dev))
return (ENXIO);
#ifdef KGDB
/*
* If this is the kgdb port, no other use is permitted.
*/
if (ISSET(sc->sc_hwflags, COM_HW_KGDB))
return (EBUSY);
#endif
tp = sc->sc_tty;
/*
* If the device is exclusively for kernel use, deny userland
* open.
*/
if (ISSET(tp->t_state, TS_KERN_ONLY))
return (EBUSY);
if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
return (EBUSY);
s = spltty();
/*
* Do the following iff this is a first open.
*/
if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
struct termios t;
struct timeval now, diff;
/* Fetch the current modem control status, needed later. */
sc->sc_msr = CSR_READ_1(&sc->sc_regs, COM_REG_MSR);
/* Clear PPS capture state on first open. */
mutex_spin_enter(&timecounter_lock);
memset(&sc->sc_pps_state, 0, sizeof(sc->sc_pps_state));
sc->sc_pps_state.ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR;
pps_init(&sc->sc_pps_state);
mutex_spin_exit(&timecounter_lock);
mutex_spin_exit(&sc->sc_lock);
/*
* Initialize the termios status to the defaults. Add in the
* sticky bits from TIOCSFLAGS.
*/
if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
t.c_ospeed = comcons_info.rate;
t.c_cflag = comcons_info.cflag;
} else {
t.c_ospeed = TTYDEF_SPEED;
t.c_cflag = TTYDEF_CFLAG;
}
t.c_ispeed = t.c_ospeed;
if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
SET(t.c_cflag, CLOCAL);
if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
SET(t.c_cflag, CRTSCTS);
if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
SET(t.c_cflag, MDMBUF);
/* Make sure comparam() will do something. */
tp->t_ospeed = 0;
(void) comparam(tp, &t);
tp->t_iflag = TTYDEF_IFLAG;
tp->t_oflag = TTYDEF_OFLAG;
tp->t_lflag = TTYDEF_LFLAG;
ttychars(tp);
ttsetwater(tp);
mutex_spin_enter(&sc->sc_lock);
/*
* Turn on DTR. We must always do this, even if carrier is not
* present, because otherwise we'd have to use TIOCSDTR
* immediately after setting CLOCAL, which applications do not
* expect. We always assert DTR while the device is open
* unless explicitly requested to deassert it.
*/
com_modem(sc, 1);
/* Clear the input ring, and unblock. */
sc->sc_rbput = sc->sc_rbget = sc->sc_rbuf;
sc->sc_rbavail = com_rbuf_size;
com_iflush(sc);
CLR(sc->sc_rx_flags, RX_ANY_BLOCK);
com_hwiflow(sc);
#ifdef COM_DEBUG
if (com_debug)
comstatus(sc, "comopen ");
#endif
mutex_spin_exit(&sc->sc_lock);
}
splx(s);
error = ttyopen(tp, COMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
if (error)
goto bad;
error = (*tp->t_linesw->l_open)(dev, tp);
if (error)
goto bad;
return (0);
bad:
if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
/*
* We failed to open the device, and nobody else had it opened.
* Clean up the state as appropriate.
*/
com_shutdown(sc);
}
return (error);
}
int
comclose(dev_t dev, int flag, int mode, struct lwp *l)
{
struct com_softc *sc =
device_lookup_private(&com_cd, COMUNIT(dev));
struct tty *tp = sc->sc_tty;
/* XXX This is for cons.c. */
if (!ISSET(tp->t_state, TS_ISOPEN))
return (0);
/*
* If the device is exclusively for kernel use, deny userland
* close.
*/
if (ISSET(tp->t_state, TS_KERN_ONLY))
return (0);
(*tp->t_linesw->l_close)(tp, flag);
ttyclose(tp);
if (COM_ISALIVE(sc) == 0)
return (0);
if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
/*
* Although we got a last close, the device may still be in
* use; e.g. if this was the dialout node, and there are still
* processes waiting for carrier on the non-dialout node.
*/
com_shutdown(sc);
}
return (0);
}
int
comread(dev_t dev, struct uio *uio, int flag)
{
struct com_softc *sc =
device_lookup_private(&com_cd, COMUNIT(dev));
struct tty *tp = sc->sc_tty;
switch (cmd) {
case TIOCSBRK:
com_break(sc, 1);
break;
case TIOCCBRK:
com_break(sc, 0);
break;
case TIOCSDTR:
com_modem(sc, 1);
break;
case TIOCCDTR:
com_modem(sc, 0);
break;
case TIOCGFLAGS:
*(int *)data = sc->sc_swflags;
break;
case TIOCSFLAGS:
sc->sc_swflags = *(int *)data;
break;
case TIOCMSET:
case TIOCMBIS:
case TIOCMBIC:
tiocm_to_com(sc, cmd, *(int *)data);
break;
case TIOCMGET:
*(int *)data = com_to_tiocm(sc);
break;
case PPS_IOC_CREATE:
case PPS_IOC_DESTROY:
case PPS_IOC_GETPARAMS:
case PPS_IOC_SETPARAMS:
case PPS_IOC_GETCAP:
case PPS_IOC_FETCH:
#ifdef PPS_SYNC
case PPS_IOC_KCBIND:
#endif
mutex_spin_enter(&timecounter_lock);
error = pps_ioctl(cmd, data, &sc->sc_pps_state);
mutex_spin_exit(&timecounter_lock);
break;
case TIOCDCDTIMESTAMP: /* XXX old, overloaded API used by xntpd v3 */
mutex_spin_enter(&timecounter_lock);
#ifndef PPS_TRAILING_EDGE
TIMESPEC_TO_TIMEVAL((struct timeval *)data,
&sc->sc_pps_state.ppsinfo.assert_timestamp);
#else
TIMESPEC_TO_TIMEVAL((struct timeval *)data,
&sc->sc_pps_state.ppsinfo.clear_timestamp);
#endif
mutex_spin_exit(&timecounter_lock);
break;
default:
error = EPASSTHROUGH;
break;
}
mutex_spin_exit(&sc->sc_lock);
#ifdef COM_DEBUG
if (com_debug)
comstatus(sc, "comioctl ");
#endif
switch (ISSET(cflag, CSIZE)) {
case CS5:
SET(lcr, LCR_5BITS);
break;
case CS6:
SET(lcr, LCR_6BITS);
break;
case CS7:
SET(lcr, LCR_7BITS);
break;
case CS8:
SET(lcr, LCR_8BITS);
break;
}
if (ISSET(cflag, PARENB)) {
SET(lcr, LCR_PENAB);
if (!ISSET(cflag, PARODD))
SET(lcr, LCR_PEVEN);
}
if (ISSET(cflag, CSTOPB))
SET(lcr, LCR_STOPB);
return (lcr);
}
int
comparam(struct tty *tp, struct termios *t)
{
struct com_softc *sc =
device_lookup_private(&com_cd, COMUNIT(tp->t_dev));
int ospeed;
u_char lcr;
if (COM_ISALIVE(sc) == 0)
return (EIO);
if (sc->sc_type == COM_TYPE_HAYESP) {
int prescaler, speed;
/*
* Calculate UART clock prescaler. It should be in
* range of 0 .. 3.
*/
for (prescaler = 0, speed = t->c_ospeed; prescaler < 4;
prescaler++, speed /= 2)
if ((ospeed = comspeed(speed, sc->sc_frequency,
sc->sc_type)) > 0)
break;
/* Check requested parameters. */
if (ospeed < 0)
return (EINVAL);
if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
return (EINVAL);
/*
* For the console, always force CLOCAL and !HUPCL, so that the port
* is always active.
*/
if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) ||
ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) {
SET(t->c_cflag, CLOCAL);
CLR(t->c_cflag, HUPCL);
}
/*
* If there were no changes, don't do anything. This avoids dropping
* input and improves performance when all we did was frob things like
* VMIN and VTIME.
*/
if (tp->t_ospeed == t->c_ospeed &&
tp->t_cflag == t->c_cflag)
return (0);
/*
* Set the FIFO threshold based on the receive speed.
*
* * If it's a low speed, it's probably a mouse or some other
* interactive device, so set the threshold low.
* * If it's a high speed, trim the trigger level down to prevent
* overflows.
* * Otherwise set it a bit higher.
*/
if (sc->sc_type == COM_TYPE_HAYESP) {
sc->sc_fifo = FIFO_DMA_MODE | FIFO_ENABLE | FIFO_TRIGGER_8;
} else if (sc->sc_type == COM_TYPE_TEGRA) {
sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_1;
} else if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) {
if (t->c_ospeed <= 1200)
sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_1;
else if (t->c_ospeed <= 38400)
sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_8;
else
sc->sc_fifo = FIFO_ENABLE | FIFO_TRIGGER_4;
} else {
sc->sc_fifo = 0;
}
if (sc->sc_type == COM_TYPE_INGENIC)
sc->sc_fifo |= FIFO_UART_ON;
/* And copy to tty. */
tp->t_ispeed = t->c_ospeed;
tp->t_ospeed = t->c_ospeed;
tp->t_cflag = t->c_cflag;
if (!sc->sc_heldchange) {
if (sc->sc_tx_busy) {
sc->sc_heldtbc = sc->sc_tbc;
sc->sc_tbc = 0;
sc->sc_heldchange = 1;
} else
com_loadchannelregs(sc);
}
if (!ISSET(t->c_cflag, CHWFLOW)) {
/* Disable the high water mark. */
sc->sc_r_hiwat = 0;
sc->sc_r_lowat = 0;
if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) {
CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
com_schedrx(sc);
}
if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) {
CLR(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED);
com_hwiflow(sc);
}
} else {
sc->sc_r_hiwat = com_rbuf_hiwat;
sc->sc_r_lowat = com_rbuf_lowat;
}
mutex_spin_exit(&sc->sc_lock);
/*
* Update the tty layer's idea of the carrier bit, in case we changed
* CLOCAL or MDMBUF. We don't hang up here; we only do that by
* explicit request.
*/
if (sc->sc_type == COM_TYPE_INGENIC) {
/* no DCD here */
(void) (*tp->t_linesw->l_modem)(tp, 1);
} else
(void) (*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_msr, MSR_DCD));
#ifdef COM_DEBUG
if (com_debug)
comstatus(sc, "comparam ");
#endif
if (!ISSET(t->c_cflag, CHWFLOW)) {
if (sc->sc_tx_stopped) {
sc->sc_tx_stopped = 0;
comstart(tp);
}
}
return (0);
}
void
com_iflush(struct com_softc *sc)
{
struct com_regs *regsp = &sc->sc_regs;
uint8_t fifo;
#ifdef DIAGNOSTIC
int reg;
#endif
int timo;
#ifdef DIAGNOSTIC
reg = 0xffff;
#endif
timo = 50000;
/* flush any pending I/O */
while (ISSET(CSR_READ_1(regsp, COM_REG_LSR), LSR_RXRDY)
&& --timo)
#ifdef DIAGNOSTIC
reg =
#else
(void)
#endif
CSR_READ_1(regsp, COM_REG_RXDATA);
#ifdef DIAGNOSTIC
if (!timo)
aprint_error_dev(sc->sc_dev, "com_iflush timeout %02x\n", reg);
#endif
switch (sc->sc_type) {
case COM_TYPE_16750:
case COM_TYPE_DW_APB:
/*
* Reset all Rx/Tx FIFO, preserve current FIFO length.
* This should prevent triggering busy interrupt while
* manipulating divisors.
*/
fifo = CSR_READ_1(regsp, COM_REG_FIFO) & (FIFO_TRIGGER_1 |
FIFO_TRIGGER_4 | FIFO_TRIGGER_8 | FIFO_TRIGGER_14);
CSR_WRITE_1(regsp, COM_REG_FIFO,
fifo | FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST);
delay(100);
break;
}
}
end = sc->sc_ebuf;
get = sc->sc_rbget;
scc = cc = com_rbuf_size - sc->sc_rbavail;
if (cc == com_rbuf_size) {
sc->sc_floods++;
if (sc->sc_errors++ == 0)
callout_reset(&sc->sc_diag_callout, 60 * hz,
comdiag, sc);
}
/* If not yet open, drop the entire buffer content here */
if (!ISSET(tp->t_state, TS_ISOPEN)) {
get += cc << 1;
if (get >= end)
get -= com_rbuf_size << 1;
cc = 0;
}
while (cc) {
code = get[0];
lsr = get[1];
if (ISSET(lsr, LSR_OE | LSR_BI | LSR_FE | LSR_PE)) {
if (ISSET(lsr, LSR_OE)) {
sc->sc_overflows++;
if (sc->sc_errors++ == 0)
callout_reset(&sc->sc_diag_callout,
60 * hz, comdiag, sc);
}
if (ISSET(lsr, LSR_BI | LSR_FE))
SET(code, TTY_FE);
if (ISSET(lsr, LSR_PE))
SET(code, TTY_PE);
}
if ((*rint)(code, tp) == -1) {
/*
* The line discipline's buffer is out of space.
*/
if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) {
/*
* We're either not using flow control, or the
* line discipline didn't tell us to block for
* some reason. Either way, we have no way to
* know when there's more space available, so
* just drop the rest of the data.
*/
get += cc << 1;
if (get >= end)
get -= com_rbuf_size << 1;
cc = 0;
} else {
/*
* Don't schedule any more receive processing
* until the line discipline tells us there's
* space available (through comhwiflow()).
* Leave the rest of the data in the input
* buffer.
*/
SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED);
}
break;
}
get += 2;
if (get >= end)
get = sc->sc_rbuf;
cc--;
}
if (cc != scc) {
sc->sc_rbget = get;
mutex_spin_enter(&sc->sc_lock);
cc = sc->sc_rbavail += scc - cc;
/* Buffers should be ok again, release possible block. */
if (cc >= sc->sc_r_lowat) {
if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
SET(sc->sc_ier, IER_ERXRDY);
if (sc->sc_type == COM_TYPE_PXA2x0)
SET(sc->sc_ier, IER_ERXTOUT);
if (sc->sc_type == COM_TYPE_INGENIC ||
sc->sc_type == COM_TYPE_TEGRA)
SET(sc->sc_ier, IER_ERXTOUT);
end = sc->sc_ebuf;
put = sc->sc_rbput;
cc = sc->sc_rbavail;
if (ISSET(iir, IIR_NOPEND)) {
if (ISSET(sc->sc_hwflags, COM_HW_BROKEN_ETXRDY))
goto do_tx;
mutex_spin_exit(&sc->sc_lock);
return (0);
}
again: do {
u_char msr, delta;
lsr = CSR_READ_1(regsp, COM_REG_LSR);
if (ISSET(lsr, LSR_BI)) {
int cn_trapped = 0; /* see above: cn_trap() */
cn_check_magic(sc->sc_tty->t_dev,
CNC_BREAK, com_cnm_state);
if (cn_trapped)
continue;
#if defined(KGDB) && !defined(DDB)
if (ISSET(sc->sc_hwflags, COM_HW_KGDB)) {
kgdb_connect(1);
continue;
}
#endif
}
if (sc->sc_type == COM_TYPE_BCMAUXUART && ISSET(iir, IIR_RXRDY))
lsr |= LSR_RXRDY;
if (ISSET(lsr, LSR_RCV_MASK) &&
!ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) {
while (cc > 0) {
int cn_trapped = 0;
put[0] = CSR_READ_1(regsp, COM_REG_RXDATA);
put[1] = lsr;
cn_check_magic(sc->sc_tty->t_dev,
put[0], com_cnm_state);
if (cn_trapped)
goto next;
put += 2;
if (put >= end)
put = sc->sc_rbuf;
cc--;
next:
lsr = CSR_READ_1(regsp, COM_REG_LSR);
if (!ISSET(lsr, LSR_RCV_MASK))
break;
}
/*
* Current string of incoming characters ended because
* no more data was available or we ran out of space.
* Schedule a receive event if any data was received.
* If we're out of space, turn off receive interrupts.
*/
sc->sc_rbput = put;
sc->sc_rbavail = cc;
if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED))
sc->sc_rx_ready = 1;
/*
* See if we are in danger of overflowing a buffer. If
* so, use hardware flow control to ease the pressure.
*/
if (!ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED) &&
cc < sc->sc_r_hiwat) {
SET(sc->sc_rx_flags, RX_IBUF_BLOCKED);
com_hwiflow(sc);
}
/*
* If we're out of space, disable receive interrupts
* until the queue has drained a bit.
*/
if (!cc) {
SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED);
switch (sc->sc_type) {
case COM_TYPE_PXA2x0:
CLR(sc->sc_ier, IER_ERXRDY|IER_ERXTOUT);
break;
case COM_TYPE_INGENIC:
case COM_TYPE_TEGRA:
CLR(sc->sc_ier,
IER_ERXRDY | IER_ERXTOUT);
break;
default:
CLR(sc->sc_ier, IER_ERXRDY);
break;
}
CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
}
} else {
if ((iir & (IIR_RXRDY|IIR_TXRDY)) == IIR_RXRDY) {
(void) CSR_READ_1(regsp, COM_REG_RXDATA);
continue;
}
}
/*
* Process normal status changes
*/
if (ISSET(delta, sc->sc_msr_mask)) {
SET(sc->sc_msr_delta, delta);
/*
* Stop output immediately if we lose the output
* flow control signal or carrier detect.
*/
if (ISSET(~msr, sc->sc_msr_mask)) {
sc->sc_tbc = 0;
sc->sc_heldtbc = 0;
#ifdef COM_DEBUG
if (com_debug)
comstatus(sc, "comintr ");
#endif
}
sc->sc_st_check = 1;
}
} while (!ISSET((iir =
CSR_READ_1(regsp, COM_REG_IIR)), IIR_NOPEND) &&
/*
* Since some device (e.g., ST16C1550) doesn't clear IIR_TXRDY
* by IIR read, so we can't do this way: `process all interrupts,
* then do TX if possible'.
*/
(iir & IIR_IMASK) != IIR_TXRDY);
do_tx:
/*
* Read LSR again, since there may be an interrupt between
* the last LSR read and IIR read above.
*/
lsr = CSR_READ_1(regsp, COM_REG_LSR);
/*
* See if data can be transmitted as well.
* Schedule tx done event if no data left
* and tty was marked busy.
*/
if (ISSET(lsr, LSR_TXRDY)) {
/*
* If we've delayed a parameter change, do it now, and restart
* output.
*/
if (sc->sc_heldchange) {
com_loadchannelregs(sc);
sc->sc_heldchange = 0;
sc->sc_tbc = sc->sc_heldtbc;
sc->sc_heldtbc = 0;
}
/* Output the next chunk of the contiguous buffer, if any. */
if (sc->sc_tbc > 0) {
u_int n;
n = sc->sc_tbc;
if (n > sc->sc_fifolen)
n = sc->sc_fifolen;
CSR_WRITE_MULTI(regsp, COM_REG_TXDATA, sc->sc_tba, n);
sc->sc_tbc -= n;
sc->sc_tba += n;
} else {
/* Disable transmit completion interrupts if necessary. */
if (ISSET(sc->sc_ier, IER_ETXRDY)) {
CLR(sc->sc_ier, IER_ETXRDY);
CSR_WRITE_1(regsp, COM_REG_IER, sc->sc_ier);
}
if (sc->sc_tx_busy) {
sc->sc_tx_busy = 0;
sc->sc_tx_done = 1;
}
}
}
if (!ISSET((iir = CSR_READ_1(regsp, COM_REG_IIR)), IIR_NOPEND))
goto again;
mutex_spin_exit(&sc->sc_lock);
/* Wake up the poller. */
if ((sc->sc_rx_ready | sc->sc_st_check | sc->sc_tx_done) != 0)
softint_schedule(sc->sc_si);
/*
* The following functions are polled getc and putc routines, shared
* by the console and kgdb glue.
*
* The read-ahead code is so that you can detect pending in-band
* cn_magic in polled mode while doing output rather than having to
* wait until the kernel decides it needs input.
*/
#define MAX_READAHEAD 20
static int com_readahead[MAX_READAHEAD];
static int com_readaheadcount = 0;
int
com_common_getc(dev_t dev, struct com_regs *regsp)
{
int s = splserial();
u_char stat, c;
/* got a character from reading things earlier */
if (com_readaheadcount > 0) {
int i;
c = com_readahead[0];
for (i = 1; i < com_readaheadcount; i++) {
com_readahead[i-1] = com_readahead[i];
}
com_readaheadcount--;
splx(s);
return (c);
}
/* don't block until a character becomes available */
if (!ISSET(stat = CSR_READ_1(regsp, COM_REG_LSR), LSR_RXRDY)) {
splx(s);
return -1;
}
c = CSR_READ_1(regsp, COM_REG_RXDATA);
stat = CSR_READ_1(regsp, COM_REG_IIR);
{
int cn_trapped = 0; /* required by cn_trap, see above */
if (!db_active)
cn_check_magic(dev, c, com_cnm_state);
}
splx(s);
return (c);
}
static void
com_common_putc(dev_t dev, struct com_regs *regsp, int c, int with_readahead)
{
int s = splserial();
int cin, stat, timo;
if (type == COM_TYPE_OMAP) {
/* setup the fifos. the FCR value is not used as long
as SCR[6] and SCR[7] are 0, which they are at reset
and we never touch the SCR register */
uint8_t rx_fifo_trig = 40;
uint8_t tx_fifo_trig = 60;
uint8_t rx_start = 8;
uint8_t rx_halt = 60;
uint8_t tlr_value = ((rx_fifo_trig>>2) << 4) | (tx_fifo_trig>>2);
uint8_t tcr_value = ((rx_start>>2) << 4) | (rx_halt>>2);
/*
* dummy_bsh required because com_init_regs() wants it. A
* real bus_space_handle will be filled in by cominit() later.
* XXXJRT Detangle this mess eventually, plz.
*/
com_init_regs(®s, iot, dummy_bsh/*XXX*/, iobase);
/*
* XXXfvdl this shouldn't be needed, but the cn_magic goo
* expects this to be initialized
*/
cn_init_magic(&com_cnm_state);
cn_set_magic("\047\001");
}
kgdb_attach(com_kgdb_getc, com_kgdb_putc, NULL);
kgdb_dev = 123; /* unneeded, only to satisfy some tests */
return (0);
}
int
com_kgdb_attach(bus_space_tag_t iot, bus_addr_t iobase, int rate,
int frequency, int type, tcflag_t cflag)
{
struct com_regs regs;
/*
* helper function to identify the com ports used by
* console or KGDB (and not yet autoconf attached)
*/
int
com_is_console(bus_space_tag_t iot, bus_addr_t iobase, bus_space_handle_t *ioh)
{
bus_space_handle_t help;
if (!comconsattached &&
bus_space_is_equal(iot, comcons_info.regs.cr_iot) &&
iobase == comcons_info.regs.cr_iobase)
help = comcons_info.regs.cr_ioh;
#ifdef KGDB
else if (!com_kgdb_attached &&
bus_space_is_equal(iot, comkgdbregs.cr_iot) &&
iobase == comkgdbregs.cr_iobase)
help = comkgdbregs.cr_ioh;
#endif
else
return (0);
if (ioh)
*ioh = help;
return (1);
}
/*
* this routine exists to serve as a shutdown hook for systems that
* have firmware which doesn't interact properly with a com device in
* FIFO mode.
*/
bool
com_cleanup(device_t self, int how)
{
struct com_softc *sc = device_private(self);
if (ISSET(sc->sc_hwflags, COM_HW_FIFO))
CSR_WRITE_1(&sc->sc_regs, COM_REG_FIFO, 0);
