Differential D20335 Diff 59964 head/sys/amd64/vmm/io/vatpit.c

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head/sys/amd64/vmm/io/vatpit.c

/*-		/*-
* Copyright (c) 2014 Tycho Nightingale <tycho.nightingale@pluribusnetworks.com>		* Copyright (c) 2014 Tycho Nightingale <tycho.nightingale@pluribusnetworks.com>
* Copyright (c) 2011 NetApp, Inc.		* Copyright (c) 2011 NetApp, Inc.
* All rights reserved.		* All rights reserved.
		* Copyright (c) 2018 Joyent, Inc.
*		*
* Redistribution and use in source and binary forms, with or without		* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions		* modification, are permitted provided that the following conditions
* are met:		* are met:
* 1. Redistributions of source code must retain the above copyright		* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.		* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright		* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the		* notice, this list of conditions and the following disclaimer in the
▲ Show 20 Lines • Show All 60 Lines • ▼ Show 20 Lines	struct vatpit_callout_arg {
struct vatpit *vatpit;		struct vatpit *vatpit;
int channel_num;		int channel_num;
};		};


struct channel {		struct channel {
int mode;		int mode;
uint16_t initial; /* initial counter value */		uint16_t initial; /* initial counter value */
sbintime_t now_sbt; /* uptime when counter was loaded */		struct bintime now_bt; /* uptime when counter was loaded */
uint8_t cr[2];		uint8_t cr[2];
uint8_t ol[2];		uint8_t ol[2];
bool slatched; /* status latched */		bool slatched; /* status latched */
uint8_t status;		uint8_t status;
int crbyte;		int crbyte;
int olbyte;		int olbyte;
int frbyte;		int frbyte;
struct callout callout;		struct callout callout;
sbintime_t callout_sbt; /* target time */		struct bintime callout_bt; /* target time */
struct vatpit_callout_arg callout_arg;		struct vatpit_callout_arg callout_arg;
};		};

struct vatpit {		struct vatpit {
struct vm *vm;		struct vm *vm;
struct mtx mtx;		struct mtx mtx;

sbintime_t freq_sbt;		struct bintime freq_bt;

struct channel channel[3];		struct channel channel[3];
};		};

static void pit_timer_start_cntr0(struct vatpit *vatpit);		static void pit_timer_start_cntr0(struct vatpit *vatpit);

		static uint64_t
		vatpit_delta_ticks(struct vatpit vatpit, struct channel c)
		{
		struct bintime delta;
		uint64_t result;

		binuptime(&delta);
		bintime_sub(&delta, &c->now_bt);

		result = delta.sec * PIT_8254_FREQ;
		result += delta.frac / vatpit->freq_bt.frac;

		return (result);
		}

static int		static int
vatpit_get_out(struct vatpit *vatpit, int channel)		vatpit_get_out(struct vatpit *vatpit, int channel)
{		{
struct channel *c;		struct channel *c;
sbintime_t delta_ticks;		uint64_t delta_ticks;
int out;		int out;

c = &vatpit->channel[channel];		c = &vatpit->channel[channel];

switch (c->mode) {		switch (c->mode) {
case TIMER_INTTC:		case TIMER_INTTC:
delta_ticks = (sbinuptime() - c->now_sbt) / vatpit->freq_sbt;		delta_ticks = vatpit_delta_ticks(vatpit, c);
out = ((c->initial - delta_ticks) <= 0);		out = (delta_ticks >= c->initial);
break;		break;
default:		default:
out = 0;		out = 0;
break;		break;
}		}

return (out);		return (out);
}		}
Show All 33 Lines	done:
VATPIT_UNLOCK(vatpit);		VATPIT_UNLOCK(vatpit);
return;		return;
}		}

static void		static void
pit_timer_start_cntr0(struct vatpit *vatpit)		pit_timer_start_cntr0(struct vatpit *vatpit)
{		{
struct channel *c;		struct channel *c;
sbintime_t now, delta, precision;		struct bintime now, delta;
		sbintime_t precision;

c = &vatpit->channel[0];		c = &vatpit->channel[0];
if (c->initial != 0) {		if (c->initial != 0) {
delta = c->initial * vatpit->freq_sbt;		delta.sec = 0;
precision = delta >> tc_precexp;		delta.frac = vatpit->freq_bt.frac * c->initial;
c->callout_sbt = c->callout_sbt + delta;		bintime_add(&c->callout_bt, &delta);
		precision = bttosbt(delta) >> tc_precexp;

/*		/*
* Reset 'callout_sbt' if the time that the callout		* Reset 'callout_bt' if the time that the callout
* was supposed to fire is more than 'c->initial'		* was supposed to fire is more than 'c->initial'
* ticks in the past.		* ticks in the past.
*/		*/
now = sbinuptime();		binuptime(&now);
if (c->callout_sbt < now)		if (bintime_cmp(&c->callout_bt, &now, <)) {
c->callout_sbt = now + delta;		c->callout_bt = now;
		bintime_add(&c->callout_bt, &delta);
		}

callout_reset_sbt(&c->callout, c->callout_sbt,		callout_reset_sbt(&c->callout, bttosbt(c->callout_bt),
precision, vatpit_callout_handler, &c->callout_arg,		precision, vatpit_callout_handler, &c->callout_arg,
C_ABSOLUTE);		C_ABSOLUTE);
}		}
}		}

static uint16_t		static uint16_t
pit_update_counter(struct vatpit vatpit, struct channel c, bool latch)		pit_update_counter(struct vatpit vatpit, struct channel c, bool latch)
{		{
uint16_t lval;		uint16_t lval;
sbintime_t delta_ticks;		uint64_t delta_ticks;

/* cannot latch a new value until the old one has been consumed */		/* cannot latch a new value until the old one has been consumed */
if (latch && c->olbyte != 0)		if (latch && c->olbyte != 0)
return (0);		return (0);

if (c->initial == 0) {		if (c->initial == 0) {
/*		/*
* This is possibly an o/s bug - reading the value of		* This is possibly an o/s bug - reading the value of
* the timer without having set up the initial value.		* the timer without having set up the initial value.
*		*
* The original user-space version of this code set		* The original user-space version of this code set
* the timer to 100hz in this condition; do the same		* the timer to 100hz in this condition; do the same
* here.		* here.
*/		*/
c->initial = TIMER_DIV(PIT_8254_FREQ, 100);		c->initial = TIMER_DIV(PIT_8254_FREQ, 100);
c->now_sbt = sbinuptime();		binuptime(&c->now_bt);
c->status &= ~TIMER_STS_NULLCNT;		c->status &= ~TIMER_STS_NULLCNT;
}		}

delta_ticks = (sbinuptime() - c->now_sbt) / vatpit->freq_sbt;		delta_ticks = vatpit_delta_ticks(vatpit, c);

lval = c->initial - delta_ticks % c->initial;		lval = c->initial - delta_ticks % c->initial;

if (latch) {		if (latch) {
c->olbyte = 2;		c->olbyte = 2;
c->ol[1] = lval; /* LSB */		c->ol[1] = lval; /* LSB */
c->ol[0] = lval >> 8; /* MSB */		c->ol[0] = lval >> 8; /* MSB */
}		}

▲ Show 20 Lines • Show All 154 Lines • ▼ Show 20 Lines	if (c->olbyte == 0) {
*eax = c->ol[--c->olbyte];		*eax = c->ol[--c->olbyte];
} else {		} else {
c->cr[c->crbyte++] = *eax;		c->cr[c->crbyte++] = *eax;
if (c->crbyte == 2) {		if (c->crbyte == 2) {
c->status &= ~TIMER_STS_NULLCNT;		c->status &= ~TIMER_STS_NULLCNT;
c->frbyte = 0;		c->frbyte = 0;
c->crbyte = 0;		c->crbyte = 0;
c->initial = c->cr[0] \| (uint16_t)c->cr[1] << 8;		c->initial = c->cr[0] \| (uint16_t)c->cr[1] << 8;
c->now_sbt = sbinuptime();		binuptime(&c->now_bt);
/* Start an interval timer for channel 0 */		/* Start an interval timer for channel 0 */
if (port == TIMER_CNTR0) {		if (port == TIMER_CNTR0) {
c->callout_sbt = c->now_sbt;		c->callout_bt = c->now_bt;
pit_timer_start_cntr0(vatpit);		pit_timer_start_cntr0(vatpit);
}		}
if (c->initial == 0)		if (c->initial == 0)
c->initial = 0xffff;		c->initial = 0xffff;
}		}
}		}
VATPIT_UNLOCK(vatpit);		VATPIT_UNLOCK(vatpit);

Show All 20 Lines	vatpit_nmisc_handler(struct vm *vm, int vcpuid, bool in, int port, int bytes,

return (0);		return (0);
}		}

struct vatpit *		struct vatpit *
vatpit_init(struct vm *vm)		vatpit_init(struct vm *vm)
{		{
struct vatpit *vatpit;		struct vatpit *vatpit;
struct bintime bt;
struct vatpit_callout_arg *arg;		struct vatpit_callout_arg *arg;
int i;		int i;

vatpit = malloc(sizeof(struct vatpit), M_VATPIT, M_WAITOK \| M_ZERO);		vatpit = malloc(sizeof(struct vatpit), M_VATPIT, M_WAITOK \| M_ZERO);
vatpit->vm = vm;		vatpit->vm = vm;

mtx_init(&vatpit->mtx, "vatpit lock", NULL, MTX_SPIN);		mtx_init(&vatpit->mtx, "vatpit lock", NULL, MTX_SPIN);

FREQ2BT(PIT_8254_FREQ, &bt);		FREQ2BT(PIT_8254_FREQ, &vatpit->freq_bt);
vatpit->freq_sbt = bttosbt(bt);

for (i = 0; i < 3; i++) {		for (i = 0; i < 3; i++) {
callout_init(&vatpit->channel[i].callout, 1);		callout_init(&vatpit->channel[i].callout, 1);
arg = &vatpit->channel[i].callout_arg;		arg = &vatpit->channel[i].callout_arg;
arg->vatpit = vatpit;		arg->vatpit = vatpit;
arg->channel_num = i;		arg->channel_num = i;
}		}

Show All 13 Lines