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author	Jason Evans <jasone@FreeBSD.org>	2000-09-07 01:33:02 +0000
committer	Jason Evans <jasone@FreeBSD.org>	2000-09-07 01:33:02 +0000
commit	0384fff8c5b098545c3db311b0e0aa1ec4c9ae7e (patch)
tree	bc6e36e781569f3efe04995c0b0befebb9154ef5 /sys/i386/isa/cy.c
parent	62ae6c89ad2b03770097d05590093f93b9d94e08 (diff)
download	src-0384fff8c5b098545c3db311b0e0aa1ec4c9ae7e.tar.gz src-0384fff8c5b098545c3db311b0e0aa1ec4c9ae7e.zip

Major update to the way synchronization is done in the kernel. Highlights

include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh

Notes

Notes: svn path=/head/; revision=65557

Diffstat (limited to 'sys/i386/isa/cy.c')

-rw-r--r--

sys/i386/isa/cy.c

197

1 files changed, 144 insertions, 53 deletions

diff --git a/sys/i386/isa/cy.c b/sys/i386/isa/cy.c
index 52a8cf36892f..5487d8fe6299 100644
--- a/sys/i386/isa/cy.c
+++ b/sys/i386/isa/cy.c

@@ -94,11 +94,6 @@

#error "The cy device requires the old isa compatibility shims"

#endif

-#ifdef SMP

-#define disable_intr() COM_DISABLE_INTR()

-#define enable_intr() COM_ENABLE_INTR()

-#endif /* SMP */

* Dictionary so that I can name everything *sio* or *com* to compare with

* sio.c. There is also lots of ugly formatting and unnecessary ifdefs to

@@ -366,7 +361,7 @@ static struct com_s *p_com_addr[NSIO];

#define com_addr(unit) (p_com_addr[unit])

struct isa_driver siodriver = {

- INTR_TYPE_TTY | INTR_TYPE_FAST,

+ INTR_TYPE_TTY | INTR_FAST,

sioprobe,

sioattach,

driver_name

@@ -604,11 +599,9 @@ cyattach_common(cy_iobase, cy_align)

com->lt_out.c_cflag = com->lt_in.c_cflag = CLOCAL;

}

if (siosetwater(com, com->it_in.c_ispeed) != 0) {

- enable_intr();

free(com, M_DEVBUF);

return (0);

}

- enable_intr();

termioschars(&com->it_in);

com->it_in.c_ispeed = com->it_in.c_ospeed = comdefaultrate;

com->it_out = com->it_in;

@@ -662,6 +655,7 @@ sioopen(dev, flag, mode, p)

int s;

struct tty *tp;

int unit;

+ int intrsave;

mynor = minor(dev);

unit = MINOR_TO_UNIT(mynor);

@@ -768,14 +762,17 @@ open_top:

}

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

(void) inb(com->line_status_port);

(void) inb(com->data_port);

com->prev_modem_status = com->last_modem_status

= inb(com->modem_status_port);

outb(iobase + com_ier, IER_ERXRDY | IER_ETXRDY | IER_ERLS

| IER_EMSC);

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

#else /* !0 */

* Flush fifos. This requires a full channel reset which

@@ -786,13 +783,16 @@ open_top:

CD1400_CCR_CMDRESET | CD1400_CCR_CHANRESET);

cd1400_channel_cmd(com, com->channel_control);

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

com->prev_modem_status = com->last_modem_status

= cd_getreg(com, CD1400_MSVR2);

cd_setreg(com, CD1400_SRER,

com->intr_enable

= CD1400_SRER_MDMCH | CD1400_SRER_RXDATA);

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

#endif /* 0 */

* Handle initial DCD. Callout devices get a fake initial

@@ -875,6 +875,7 @@ comhardclose(com)

int s;

struct tty *tp;

int unit;

+ int intrsave;

unit = com->unit;

iobase = com->iobase;

@@ -888,10 +889,13 @@ comhardclose(com)

outb(iobase + com_cfcr, com->cfcr_image &= ~CFCR_SBREAK);

#else

/* XXX */

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

com->etc = ETC_NONE;

cd_setreg(com, CD1400_COR2, com->cor[1] &= ~CD1400_COR2_ETC);

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

cd1400_channel_cmd(com, CD1400_CCR_CMDRESET | CD1400_CCR_FTF);

#endif

@@ -899,9 +903,12 @@ comhardclose(com)

#if 0

outb(iobase + com_ier, 0);

#else

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

cd_setreg(com, CD1400_SRER, com->intr_enable = 0);

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

#endif

tp = com->tp;

if ((tp->t_cflag & HUPCL)

@@ -991,6 +998,11 @@ siodtrwakeup(chan)

wakeup(&com->dtr_wait);

}

+/*

+ * This function:

+ * a) needs to be called with COM_LOCK() held, and

+ * b) needs to return with COM_LOCK() held.

+ */

static void

sioinput(com)

struct com_s *com;

@@ -1000,6 +1012,7 @@ sioinput(com)

u_char line_status;

int recv_data;

struct tty *tp;

+ int intrsave;

buf = com->ibuf;

tp = com->tp;

@@ -1016,7 +1029,15 @@ sioinput(com)

* slinput is reasonably fast (usually 40 instructions plus

* call overhead).

do {

+ /*

+ * This may look odd, but it is using save-and-enable

+ * semantics instead of the save-and-disable semantics

+ * that are used everywhere else.

+ */

+ intrsave = save_intr();

+ COM_UNLOCK();

enable_intr();

incc = com->iptr - buf;

if (tp->t_rawq.c_cc + incc > tp->t_ihiwat

@@ -1038,10 +1059,18 @@ sioinput(com)

tp->t_lflag &= ~FLUSHO;

comstart(tp);

}

- disable_intr();

+ restore_intr(intrsave);

+ COM_LOCK();

} while (buf < com->iptr);

} else {

do {

+ /*

+ * This may look odd, but it is using save-and-enable

+ * semantics instead of the save-and-disable semantics

+ * that are used everywhere else.

+ */

+ intrsave = save_intr();

+ COM_UNLOCK();

enable_intr();

line_status = buf[com->ierroff];

recv_data = *buf++;

@@ -1057,7 +1086,8 @@ sioinput(com)

recv_data |= TTY_PE;

}

(*linesw[tp->t_line].l_rint)(recv_data, tp);

- disable_intr();

+ restore_intr(intrsave);

+ COM_LOCK();

} while (buf < com->iptr);

}

com_events -= (com->iptr - com->ibuf);

@@ -1729,6 +1759,7 @@ static void

siopoll()

{

int unit;

+ int intrsave;

#ifdef CyDebug

++cy_timeouts;

@@ -1751,7 +1782,9 @@ repeat:

* (actually never opened devices) so that we don't

* loop.

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

incc = com->iptr - com->ibuf;

com->iptr = com->ibuf;

if (com->state & CS_CHECKMSR) {

@@ -1759,7 +1792,8 @@ repeat:

com->state &= ~CS_CHECKMSR;

}

com_events -= incc;

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

if (incc != 0)

log(LOG_DEBUG,

"sio%d: %d events for device with no tp\n",

@@ -1767,29 +1801,39 @@ repeat:

continue;

}

if (com->iptr != com->ibuf) {

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

sioinput(com);

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

}

if (com->state & CS_CHECKMSR) {

u_char delta_modem_status;

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

+ sioinput(com);

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();

+ COM_UNLOCK();

+ restore_intr(intrsave);

if (delta_modem_status & MSR_DCD)

(*linesw[tp->t_line].l_modem)

(tp, com->prev_modem_status & MSR_DCD);

}

if (com->extra_state & CSE_ODONE) {

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

com_events -= LOTS_OF_EVENTS;

com->extra_state &= ~CSE_ODONE;

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

if (!(com->state & CS_BUSY)) {

tp->t_state &= ~TS_BUSY;

ttwwakeup(com->tp);

@@ -1801,10 +1845,13 @@ repeat:

}

if (com->state & CS_ODONE) {

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

com_events -= LOTS_OF_EVENTS;

com->state &= ~CS_ODONE;

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

(*linesw[tp->t_line].l_start)(tp);

}

if (com_events == 0)

@@ -1833,6 +1880,7 @@ comparam(tp, t)

u_char opt;

int s;

int unit;

+ int intrsave;

/* do historical conversions */

if (t->c_ispeed == 0)

@@ -1857,14 +1905,9 @@ comparam(tp, t)

else

(void)commctl(com, TIOCM_DTR, DMBIS);

- /*

- * This returns with interrupts disabled so that we can complete

- * the speed change atomically.

- */

(void) siosetwater(com, t->c_ispeed);

/* XXX we don't actually change the speed atomically. */

- enable_intr();

if (idivisor != 0) {

cd_setreg(com, CD1400_RBPR, idivisor);

@@ -1985,12 +2028,15 @@ comparam(tp, t)

if (cflag & CCTS_OFLOW)

opt |= CD1400_COR2_CCTS_OFLOW;

#endif

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

if (opt != com->cor[1]) {

cor_change |= CD1400_CCR_COR2;

cd_setreg(com, CD1400_COR2, com->cor[1] = opt);

}

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

* set channel option register 3 -

@@ -2111,7 +2157,9 @@ comparam(tp, t)

* XXX should have done this long ago, but there is too much state

* to change all atomically.

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

com->state &= ~CS_TTGO;

if (!(tp->t_state & TS_TTSTOP))

@@ -2177,7 +2225,8 @@ comparam(tp, t)

| CD1400_SRER_TXMPTY);

}

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

splx(s);

comstart(tp);

if (com->ibufold != NULL) {

@@ -2196,6 +2245,7 @@ siosetwater(com, speed)

u_char *ibuf;

int ibufsize;

struct tty *tp;

+ int intrsave;

* Make the buffer size large enough to handle a softtty interrupt

@@ -2207,7 +2257,6 @@ siosetwater(com, speed)

for (ibufsize = 128; ibufsize < cp4ticks;)

ibufsize <<= 1;

if (ibufsize == com->ibufsize) {

- disable_intr();

return (0);

}

@@ -2217,7 +2266,6 @@ siosetwater(com, speed)

ibuf = malloc(2 * ibufsize, M_DEVBUF, M_NOWAIT);

if (ibuf == NULL) {

- disable_intr();

return (ENOMEM);

}

@@ -2235,7 +2283,9 @@ siosetwater(com, speed)

* Read current input buffer, if any. Continue with interrupts

* disabled.

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

if (com->iptr != com->ibuf)

sioinput(com);

@@ -2254,6 +2304,9 @@ siosetwater(com, speed)

com->ibufend = ibuf + ibufsize;

com->ierroff = ibufsize;

com->ihighwater = ibuf + 3 * ibufsize / 4;

+ COM_UNLOCK();

+ restore_intr(intrsave);

return (0);

}

@@ -2267,6 +2320,7 @@ comstart(tp)

bool_t started;

#endif

int unit;

+ int intrsave;

unit = DEV_TO_UNIT(tp->t_dev);

com = com_addr(unit);

@@ -2277,7 +2331,9 @@ comstart(tp)

started = FALSE;

#endif

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

if (tp->t_state & TS_TTSTOP) {

com->state &= ~CS_TTGO;

if (com->intr_enable & CD1400_SRER_TXRDY)

@@ -2313,7 +2369,8 @@ comstart(tp)

com->mcr_image |= com->mcr_rts);

#endif

}

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

if (tp->t_state & (TS_TIMEOUT | TS_TTSTOP)) {

ttwwakeup(tp);

splx(s);

@@ -2332,7 +2389,9 @@ comstart(tp)

sizeof com->obuf1);

com->obufs[0].l_next = NULL;

com->obufs[0].l_queued = TRUE;

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

if (com->state & CS_BUSY) {

qp = com->obufq.l_next;

while ((next = qp->l_next) != NULL)

@@ -2351,7 +2410,8 @@ comstart(tp)

& ~CD1400_SRER_TXMPTY)

| CD1400_SRER_TXRDY);

}

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

}

if (tp->t_outq.c_cc != 0 && !com->obufs[1].l_queued) {

#ifdef CyDebug

@@ -2362,7 +2422,9 @@ comstart(tp)

sizeof com->obuf2);

com->obufs[1].l_next = NULL;

com->obufs[1].l_queued = TRUE;

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

if (com->state & CS_BUSY) {

qp = com->obufq.l_next;

while ((next = qp->l_next) != NULL)

@@ -2381,7 +2443,8 @@ comstart(tp)

& ~CD1400_SRER_TXMPTY)

| CD1400_SRER_TXRDY);

}

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

}

tp->t_state |= TS_BUSY;

}

@@ -2390,10 +2453,13 @@ comstart(tp)

++com->start_real;

#endif

#if 0

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

if (com->state >= (CS_BUSY | CS_TTGO))

siointr1(com); /* fake interrupt to start output */

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

#endif

ttwwakeup(tp);

splx(s);

@@ -2406,10 +2472,13 @@ comstop(tp, rw)

{

struct com_s *com;

bool_t wakeup_etc;

+ int intrsave;

com = com_addr(DEV_TO_UNIT(tp->t_dev));

wakeup_etc = FALSE;

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

if (rw & FWRITE) {

com->obufs[0].l_queued = FALSE;

com->obufs[1].l_queued = FALSE;

@@ -2432,7 +2501,8 @@ comstop(tp, rw)

com_events -= (com->iptr - com->ibuf);

com->iptr = com->ibuf;

}

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

if (wakeup_etc)

wakeup(&com->etc);

if (rw & FWRITE && com->etc == ETC_NONE)

@@ -2448,6 +2518,7 @@ commctl(com, bits, how)

{

int mcr;

int msr;

+ int intrsave;

if (how == DMGET) {

if (com->channel_control & CD1400_CCR_RCVEN)

@@ -2485,7 +2556,9 @@ commctl(com, bits, how)

mcr |= com->mcr_dtr;

if (bits & TIOCM_RTS)

mcr |= com->mcr_rts;

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

switch (how) {

case DMSET:

com->mcr_image = mcr;

@@ -2503,7 +2576,8 @@ commctl(com, bits, how)

cd_setreg(com, CD1400_MSVR2, mcr);

break;

}

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

return (0);

}

@@ -2565,9 +2639,14 @@ comwakeup(chan)

com = com_addr(unit);

if (com != NULL

&& (com->state >= (CS_BUSY | CS_TTGO) || com->poll)) {

+ int intrsave;

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

siointr1(com);

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

}

#endif

@@ -2587,11 +2666,15 @@ comwakeup(chan)

for (errnum = 0; errnum < CE_NTYPES; ++errnum) {

u_int delta;

u_long total;

+ int intrsave;

+ intrsave = save_intr();

disable_intr();

+ COM_LOCK();

delta = com->delta_error_counts[errnum];

com->delta_error_counts[errnum] = 0;

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

if (delta == 0)

continue;

total = com->error_counts[errnum] += delta;

@@ -2743,6 +2826,8 @@ cd_etc(com, etc)

struct com_s *com;

int etc;

{

+ int intrsave;

* We can't change the hardware's ETC state while there are any

* characters in the tx fifo, since those characters would be

@@ -2754,26 +2839,28 @@ cd_etc(com, etc)

* for the tx to become empty so that the command is sure to be

* executed soon after we issue it.

+ intrsave = save_intr();

disable_intr();

- if (com->etc == etc) {

- enable_intr();

+ COM_LOCK();

+ if (com->etc == etc)

goto wait;

- }

if ((etc == CD1400_ETC_SENDBREAK

&& (com->etc == ETC_BREAK_STARTING

|| com->etc == ETC_BREAK_STARTED))

|| (etc == CD1400_ETC_STOPBREAK

&& (com->etc == ETC_BREAK_ENDING || com->etc == ETC_BREAK_ENDED

|| com->etc == ETC_NONE))) {

- enable_intr();

+ COM_UNLOCK();

+ restore_intr(intrsave);

return;

}

com->etc = etc;

cd_setreg(com, CD1400_SRER,

com->intr_enable

= (com->intr_enable & ~CD1400_SRER_TXRDY) | CD1400_SRER_TXMPTY);

- enable_intr();

wait:

+ COM_UNLOCK();

+ restore_intr(intrsave);

while (com->etc == etc

&& tsleep(&com->etc, TTIPRI | PCATCH, "cyetc", 0) == 0)

continue;

@@ -2787,7 +2874,7 @@ cd_getreg(com, reg)

struct com_s *basecom;

u_char car;

int cy_align;

- u_long ef;

+ int intrsave;

cy_addr iobase;

int val;

@@ -2795,14 +2882,16 @@ cd_getreg(com, reg)

car = com->unit & CD1400_CAR_CHAN;

cy_align = com->cy_align;

iobase = com->iobase;

- ef = read_eflags();

- if (ef & PSL_I)

- disable_intr();

+ intrsave = save_intr();

+ disable_intr();

+ if (intrsave & PSL_I)

+ COM_LOCK();

if (basecom->car != car)

cd_outb(iobase, CD1400_CAR, cy_align, basecom->car = car);

val = cd_inb(iobase, reg, cy_align);

- if (ef & PSL_I)

- enable_intr();

+ if (intrsave & PSL_I)

+ COM_UNLOCK();

+ restore_intr(intrsave);

return (val);

}

@@ -2815,21 +2904,23 @@ cd_setreg(com, reg, val)

struct com_s *basecom;

u_char car;

int cy_align;

- u_long ef;

+ int intrsave;

cy_addr iobase;

basecom = com_addr(com->unit & ~(CD1400_NO_OF_CHANNELS - 1));

car = com->unit & CD1400_CAR_CHAN;

cy_align = com->cy_align;

iobase = com->iobase;

- ef = read_eflags();

- if (ef & PSL_I)

- disable_intr();

+ intrsave = save_intr();

+ disable_intr();

+ if (intrsave & PSL_I)

+ COM_LOCK();

if (basecom->car != car)

cd_outb(iobase, CD1400_CAR, cy_align, basecom->car = car);

cd_outb(iobase, reg, cy_align, val);

- if (ef & PSL_I)

- enable_intr();

+ if (intrsave & PSL_I)

+ COM_UNLOCK();

+ restore_intr(intrsave);

}

#ifdef CyDebug