/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2014, Neel Natu (neel@freebsd.org)
* 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 unmodified, 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>
#include "opt_bhyve_snapshot.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/queue.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/clock.h>
#include <sys/sysctl.h>
#include <machine/vmm.h>
#include <machine/vmm_snapshot.h>
#include <isa/rtc.h>
#include "vmm_ktr.h"
#include "vatpic.h"
#include "vioapic.h"
#include "vrtc.h"
/* Register layout of the RTC */
struct rtcdev {
uint8_t sec;
uint8_t alarm_sec;
uint8_t min;
uint8_t alarm_min;
uint8_t hour;
uint8_t alarm_hour;
uint8_t day_of_week;
uint8_t day_of_month;
uint8_t month;
uint8_t year;
uint8_t reg_a;
uint8_t reg_b;
uint8_t reg_c;
uint8_t reg_d;
uint8_t nvram[36];
uint8_t century;
uint8_t nvram2[128 - 51];
} __packed;
CTASSERT(sizeof(struct rtcdev) == 128);
CTASSERT(offsetof(struct rtcdev, century) == RTC_CENTURY);
struct vrtc {
struct vm *vm;
struct mtx mtx;
struct callout callout;
u_int addr; /* RTC register to read or write */
sbintime_t base_uptime;
time_t base_rtctime;
struct rtcdev rtcdev;
};
#define VRTC_LOCK(vrtc) mtx_lock(&((vrtc)->mtx))
#define VRTC_UNLOCK(vrtc) mtx_unlock(&((vrtc)->mtx))
#define VRTC_LOCKED(vrtc) mtx_owned(&((vrtc)->mtx))
/*
* RTC time is considered "broken" if:
* - RTC updates are halted by the guest
* - RTC date/time fields have invalid values
*/
#define VRTC_BROKEN_TIME ((time_t)-1)
#define RTC_IRQ 8
#define RTCSB_BIN 0x04
#define RTCSB_ALL_INTRS (RTCSB_UINTR | RTCSB_AINTR | RTCSB_PINTR)
#define rtc_halted(vrtc) ((vrtc->rtcdev.reg_b & RTCSB_HALT) != 0)
#define aintr_enabled(vrtc) (((vrtc)->rtcdev.reg_b & RTCSB_AINTR) != 0)
#define pintr_enabled(vrtc) (((vrtc)->rtcdev.reg_b & RTCSB_PINTR) != 0)
#define uintr_enabled(vrtc) (((vrtc)->rtcdev.reg_b & RTCSB_UINTR) != 0)
static void vrtc_callout_handler(void *arg);
static void vrtc_set_reg_c(struct vrtc *vrtc, uint8_t newval);
static MALLOC_DEFINE(M_VRTC, "vrtc", "bhyve virtual rtc");
SYSCTL_DECL(_hw_vmm);
SYSCTL_NODE(_hw_vmm, OID_AUTO, vrtc, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
NULL);
static int rtc_flag_broken_time = 1;
SYSCTL_INT(_hw_vmm_vrtc, OID_AUTO, flag_broken_time, CTLFLAG_RDTUN,
&rtc_flag_broken_time, 0, "Stop guest when invalid RTC time is detected");
static __inline bool
divider_enabled(int reg_a)
{
/*
* The RTC is counting only when dividers are not held in reset.
*/
return ((reg_a & 0x70) == 0x20);
}
static __inline bool
update_enabled(struct vrtc *vrtc)
{
/*
* RTC date/time can be updated only if:
* - divider is not held in reset
* - guest has not disabled updates
* - the date/time fields have valid contents
*/
if (!divider_enabled(vrtc->rtcdev.reg_a))
return (false);
if (rtc_halted(vrtc))
return (false);
if (vrtc->base_rtctime == VRTC_BROKEN_TIME)
return (false);
return (true);
}
static time_t
vrtc_curtime(struct vrtc *vrtc, sbintime_t *basetime)
{
sbintime_t now, delta;
time_t t, secs;
KASSERT(VRTC_LOCKED(vrtc), ("%s: vrtc not locked", __func__));
t = vrtc->base_rtctime;
*basetime = vrtc->base_uptime;
if (update_enabled(vrtc)) {
now = sbinuptime();
delta = now - vrtc->base_uptime;
KASSERT(delta >= 0, ("vrtc_curtime: uptime went backwards: "
"%#lx to %#lx", vrtc->base_uptime, now));
secs = delta / SBT_1S;
t += secs;
*basetime += secs * SBT_1S;
}
return (t);
}
static __inline uint8_t
rtcset(struct rtcdev *rtc, int val)
{
KASSERT(val >= 0 && val < 100, ("%s: invalid bin2bcd index %d",
__func__, val));
return ((rtc->reg_b & RTCSB_BIN) ? val : bin2bcd_data[val]);
}
static void
secs_to_rtc(time_t rtctime, struct vrtc *vrtc, int force_update)
{
struct clocktime ct;
struct timespec ts;
struct rtcdev *rtc;
int hour;
KASSERT(VRTC_LOCKED(vrtc), ("%s: vrtc not locked", __func__));
if (rtctime < 0) {
KASSERT(rtctime == VRTC_BROKEN_TIME,
("%s: invalid vrtc time %#lx", __func__, rtctime));
return;
}
/*
* If the RTC is halted then the guest has "ownership" of the
* date/time fields. Don't update the RTC date/time fields in
* this case (unless forced).
*/
if (rtc_halted(vrtc) && !force_update)
return;
ts.tv_sec = rtctime;
ts.tv_nsec = 0;
clock_ts_to_ct(&ts, &ct);
KASSERT(ct.sec >= 0 && ct.sec <= 59, ("invalid clocktime sec %d",
ct.sec));
KASSERT(ct.min >= 0 && ct.min <= 59, ("invalid clocktime min %d",
ct.min));
KASSERT(ct.hour >= 0 && ct.hour <= 23, ("invalid clocktime hour %d",
ct.hour));
KASSERT(ct.dow >= 0 && ct.dow <= 6, ("invalid clocktime wday %d",
ct.dow));
KASSERT(ct.day >= 1 && ct.day <= 31, ("invalid clocktime mday %d",
ct.day));
KASSERT(ct.mon >= 1 && ct.mon <= 12, ("invalid clocktime month %d",
ct.mon));
KASSERT(ct.year >= POSIX_BASE_YEAR, ("invalid clocktime year %d",
ct.year));
rtc = &vrtc->rtcdev;
rtc->sec = rtcset(rtc, ct.sec);
rtc->min = rtcset(rtc, ct.min);
if (rtc->reg_b & RTCSB_24HR) {
hour = ct.hour;
} else {
/*
* Convert to the 12-hour format.
*/
switch (ct.hour) {
case 0: /* 12 AM */
case 12: /* 12 PM */
hour = 12;
break;
default:
/*
* The remaining 'ct.hour' values are interpreted as:
* [1 - 11] -> 1 - 11 AM
* [13 - 23] -> 1 - 11 PM
*/
hour = ct.hour % 12;
break;
}
}
rtc->hour = rtcset(rtc, hour);
if ((rtc->reg_b & RTCSB_24HR) == 0 && ct.hour >= 12)
rtc->hour |= 0x80; /* set MSB to indicate PM */
rtc->day_of_week = rtcset(rtc, ct.dow + 1);
rtc->day_of_month = rtcset(rtc, ct.day);
rtc->month = rtcset(rtc, ct.mon);
rtc->year = rtcset(rtc, ct.year % 100);
rtc->century = rtcset(rtc, ct.year / 100);
}
static int
rtcget(struct rtcdev *rtc, int val, int *retval)
{
uint8_t upper, lower;
if (rtc->reg_b & RTCSB_BIN) {
*retval = val;
return (0);
}
lower = val & 0xf;
upper = (val >> 4) & 0xf;
if (lower > 9 || upper > 9)
return (-1);
*retval = upper * 10 + lower;
return (0);
}
static time_t
rtc_to_secs(struct vrtc *vrtc)
{
struct clocktime ct;
struct timespec ts;
struct rtcdev *rtc;
#ifdef KTR
struct vm *vm = vrtc->vm;
#endif
int century, error, hour, pm, year;
KASSERT(VRTC_LOCKED(vrtc), ("%s: vrtc not locked", __func__));
rtc = &vrtc->rtcdev;
bzero(&ct, sizeof(struct clocktime));
error = rtcget(rtc, rtc->sec, &ct.sec);
if (error || ct.sec < 0 || ct.sec > 59) {
VM_CTR2(vm, "Invalid RTC sec %#x/%d", rtc->sec, ct.sec);
goto fail;
}
error = rtcget(rtc, rtc->min, &ct.min);
if (error || ct.min < 0 || ct.min > 59) {
VM_CTR2(vm, "Invalid RTC min %#x/%d", rtc->min, ct.min);
goto fail;
}
pm = 0;
hour = rtc->hour;
if ((rtc->reg_b & RTCSB_24HR) == 0) {
if (hour & 0x80) {
hour &= ~0x80;
pm = 1;
}
}
error = rtcget(rtc, hour, &ct.hour);
if ((rtc->reg_b & RTCSB_24HR) == 0) {
if (ct.hour >= 1 && ct.hour <= 12) {
/*
* Convert from 12-hour format to internal 24-hour
* representation as follows:
*
* 12-hour format ct.hour
* 12 AM 0
* 1 - 11 AM 1 - 11
* 12 PM 12
* 1 - 11 PM 13 - 23
*/
if (ct.hour == 12)
ct.hour = 0;
if (pm)
ct.hour += 12;
} else {
VM_CTR2(vm, "Invalid RTC 12-hour format %#x/%d",
rtc->hour, ct.hour);
goto fail;
}
}
if (error || ct.hour < 0 || ct.hour > 23) {
VM_CTR2(vm, "Invalid RTC hour %#x/%d", rtc->hour, ct.hour);
goto fail;
}
/*
* Ignore 'rtc->dow' because some guests like Linux don't bother
* setting it at all while others like OpenBSD/i386 set it incorrectly.
*
* clock_ct_to_ts() does not depend on 'ct.dow' anyways so ignore it.
*/
ct.dow = -1;
error = rtcget(rtc, rtc->day_of_month, &ct.day);
if (error || ct.day < 1 || ct.day > 31) {
VM_CTR2(vm, "Invalid RTC mday %#x/%d", rtc->day_of_month,
ct.day);
goto fail;
}
error = rtcget(rtc, rtc->month, &ct.mon);
if (error || ct.mon < 1 || ct.mon > 12) {
VM_CTR2(vm, "Invalid RTC month %#x/%d", rtc->month, ct.mon);
goto fail;
}
error = rtcget(rtc, rtc->year, &year);
if (error || year < 0 || year > 99) {
VM_CTR2(vm, "Invalid RTC year %#x/%d", rtc->year, year);
goto fail;
}
error = rtcget(rtc, rtc->century, ¢ury);
ct.year = century * 100 + year;
if (error || ct.year < POSIX_BASE_YEAR) {
VM_CTR2(vm, "Invalid RTC century %#x/%d", rtc->century,
ct.year);
goto fail;
}
error = clock_ct_to_ts(&ct, &ts);
if (error || ts.tv_sec < 0) {
VM_CTR3(vm, "Invalid RTC clocktime.date %04d-%02d-%02d",
ct.year, ct.mon, ct.day);
VM_CTR3(vm, "Invalid RTC clocktime.time %02d:%02d:%02d",
ct.hour, ct.min, ct.sec);
goto fail;
}
return (ts.tv_sec); /* success */
fail:
/*
* Stop updating the RTC if the date/time fields programmed by
* the guest are invalid.
*/
VM_CTR0(vrtc->vm, "Invalid RTC date/time programming detected");
return (VRTC_BROKEN_TIME);
}
static int
vrtc_time_update(struct vrtc *vrtc, time_t newtime, sbintime_t newbase)
{
struct rtcdev *rtc;
time_t oldtime;
uint8_t alarm_sec, alarm_min, alarm_hour;
KASSERT(VRTC_LOCKED(vrtc), ("%s: vrtc not locked", __func__));
rtc = &vrtc->rtcdev;
alarm_sec = rtc->alarm_sec;
alarm_min = rtc->alarm_min;
alarm_hour = rtc->alarm_hour;
oldtime = vrtc->base_rtctime;
VM_CTR2(vrtc->vm, "Updating RTC secs from %#lx to %#lx",
oldtime, newtime);
VM_CTR2(vrtc->vm, "Updating RTC base uptime from %#lx to %#lx",
vrtc->base_uptime, newbase);
vrtc->base_uptime = newbase;
if (newtime == oldtime)
return (0);
/*
* If 'newtime' indicates that RTC updates are disabled then just
* record that and return. There is no need to do alarm interrupt
* processing in this case.
*/
if (newtime == VRTC_BROKEN_TIME) {
vrtc->base_rtctime = VRTC_BROKEN_TIME;
return (0);
}
/*
* Return an error if RTC updates are halted by the guest.
*/
if (rtc_halted(vrtc)) {
VM_CTR0(vrtc->vm, "RTC update halted by guest");
return (EBUSY);
}
do {
/*
* If the alarm interrupt is enabled and 'oldtime' is valid
* then visit all the seconds between 'oldtime' and 'newtime'
* to check for the alarm condition.
*
* Otherwise move the RTC time forward directly to 'newtime'.
*/
if (aintr_enabled(vrtc) && oldtime != VRTC_BROKEN_TIME)
vrtc->base_rtctime++;
else
vrtc->base_rtctime = newtime;
if (aintr_enabled(vrtc)) {
/*
* Update the RTC date/time fields before checking
* if the alarm conditions are satisfied.
*/
secs_to_rtc(vrtc->base_rtctime, vrtc, 0);
if ((alarm_sec >= 0xC0 || alarm_sec == rtc->sec) &&
(alarm_min >= 0xC0 || alarm_min == rtc->min) &&
(alarm_hour >= 0xC0 || alarm_hour == rtc->hour)) {
vrtc_set_reg_c(vrtc, rtc->reg_c | RTCIR_ALARM);
}
}
} while (vrtc->base_rtctime != newtime);
if (uintr_enabled(vrtc))
vrtc_set_reg_c(vrtc, rtc->reg_c | RTCIR_UPDATE);
return (0);
}
static sbintime_t
vrtc_freq(struct vrtc *vrtc)
{
int ratesel;
static sbintime_t pf[16] = {
0,
SBT_1S / 256,
SBT_1S / 128,
SBT_1S / 8192,
SBT_1S / 4096,
SBT_1S / 2048,
SBT_1S / 1024,
SBT_1S / 512,
SBT_1S / 256,
SBT_1S / 128,
SBT_1S / 64,
SBT_1S / 32,
SBT_1S / 16,
SBT_1S / 8,
SBT_1S / 4,
SBT_1S / 2,
};
KASSERT(VRTC_LOCKED(vrtc), ("%s: vrtc not locked", __func__));
/*
* If both periodic and alarm interrupts are enabled then use the
* periodic frequency to drive the callout. The minimum periodic
* frequency (2 Hz) is higher than the alarm frequency (1 Hz) so
* piggyback the alarm on top of it. The same argument applies to
* the update interrupt.
*/
if (pintr_enabled(vrtc) && divider_enabled(vrtc->rtcdev.reg_a)) {
ratesel = vrtc->rtcdev.reg_a & 0xf;
return (pf[ratesel]);
} else if (aintr_enabled(vrtc) && update_enabled(vrtc)) {
return (SBT_1S);
} else if (uintr_enabled(vrtc) && update_enabled(vrtc)) {
return (SBT_1S);
} else {
return (0);
}
}
static void
vrtc_callout_reset(struct vrtc *vrtc, sbintime_t freqsbt)
{
KASSERT(VRTC_LOCKED(vrtc), ("%s: vrtc not locked", __func__));
if (freqsbt == 0) {
if (callout_active(&vrtc->callout)) {
VM_CTR0(vrtc->vm, "RTC callout stopped");
callout_stop(&vrtc->callout);
}
return;
}
VM_CTR1(vrtc->vm, "RTC callout frequency %d hz", SBT_1S / freqsbt);
callout_reset_sbt(&vrtc->callout, freqsbt, 0, vrtc_callout_handler,
vrtc, 0);
}
static void
vrtc_callout_handler(void *arg)
{
struct vrtc *vrtc = arg;
sbintime_t freqsbt, basetime;
time_t rtctime;
int error __diagused;
VM_CTR0(vrtc->vm, "vrtc callout fired");
VRTC_LOCK(vrtc);
if (callout_pending(&vrtc->callout)) /* callout was reset */
goto done;
if (!callout_active(&vrtc->callout)) /* callout was stopped */
goto done;
callout_deactivate(&vrtc->callout);
KASSERT((vrtc->rtcdev.reg_b & RTCSB_ALL_INTRS) != 0,
("gratuitous vrtc callout"));
if (pintr_enabled(vrtc))
vrtc_set_reg_c(vrtc, vrtc->rtcdev.reg_c | RTCIR_PERIOD);
if (aintr_enabled(vrtc) || uintr_enabled(vrtc)) {
rtctime = vrtc_curtime(vrtc, &basetime);
error = vrtc_time_update(vrtc, rtctime, basetime);
KASSERT(error == 0, ("%s: vrtc_time_update error %d",
__func__, error));
}
freqsbt = vrtc_freq(vrtc);
KASSERT(freqsbt != 0, ("%s: vrtc frequency cannot be zero", __func__));
vrtc_callout_reset(vrtc, freqsbt);
done:
VRTC_UNLOCK(vrtc);
}
static __inline void
vrtc_callout_check(struct vrtc *vrtc, sbintime_t freq)
{
int active __diagused;
active = callout_active(&vrtc->callout) ? 1 : 0;
KASSERT((freq == 0 && !active) || (freq != 0 && active),
("vrtc callout %s with frequency %#lx",
active ? "active" : "inactive", freq));
}
static void
vrtc_set_reg_c(struct vrtc *vrtc, uint8_t newval)
{
struct rtcdev *rtc;
int oldirqf, newirqf;
uint8_t oldval, changed;
KASSERT(VRTC_LOCKED(vrtc), ("%s: vrtc not locked", __func__));
rtc = &vrtc->rtcdev;
newval &= RTCIR_ALARM | RTCIR_PERIOD | RTCIR_UPDATE;
oldirqf = rtc->reg_c & RTCIR_INT;
if ((aintr_enabled(vrtc) && (newval & RTCIR_ALARM) != 0) ||
(pintr_enabled(vrtc) && (newval & RTCIR_PERIOD) != 0) ||
(uintr_enabled(vrtc) && (newval & RTCIR_UPDATE) != 0)) {
newirqf = RTCIR_INT;
} else {
newirqf = 0;
}
oldval = rtc->reg_c;
rtc->reg_c = newirqf | newval;
changed = oldval ^ rtc->reg_c;
if (changed) {
VM_CTR2(vrtc->vm, "RTC reg_c changed from %#x to %#x",
oldval, rtc->reg_c);
}
if (!oldirqf && newirqf) {
VM_CTR1(vrtc->vm, "RTC irq %d asserted", RTC_IRQ);
vatpic_pulse_irq(vrtc->vm, RTC_IRQ);
vioapic_pulse_irq(vrtc->vm, RTC_IRQ);
} else if (oldirqf && !newirqf) {
VM_CTR1(vrtc->vm, "RTC irq %d deasserted", RTC_IRQ);
}
}
static int
vrtc_set_reg_b(struct vrtc *vrtc, uint8_t newval)
{
struct rtcdev *rtc;
sbintime_t oldfreq, newfreq, basetime;
time_t curtime, rtctime;
int error __diagused;
uint8_t oldval, changed;
KASSERT(VRTC_LOCKED(vrtc), ("%s: vrtc not locked", __func__));
rtc = &vrtc->rtcdev;
oldval = rtc->reg_b;
oldfreq = vrtc_freq(vrtc);
rtc->reg_b = newval;
changed = oldval ^ newval;
if (changed) {
VM_CTR2(vrtc->vm, "RTC reg_b changed from %#x to %#x",
oldval, newval);
}
if (changed & RTCSB_HALT) {
if ((newval & RTCSB_HALT) == 0) {
rtctime = rtc_to_secs(vrtc);
basetime = sbinuptime();
if (rtctime == VRTC_BROKEN_TIME) {
if (rtc_flag_broken_time)
return (-1);
}
} else {
curtime = vrtc_curtime(vrtc, &basetime);
KASSERT(curtime == vrtc->base_rtctime, ("%s: mismatch "
"between vrtc basetime (%#lx) and curtime (%#lx)",
__func__, vrtc->base_rtctime, curtime));
/*
* Force a refresh of the RTC date/time fields so
* they reflect the time right before the guest set
* the HALT bit.
*/
secs_to_rtc(curtime, vrtc, 1);
/*
* Updates are halted so mark 'base_rtctime' to denote
* that the RTC date/time is in flux.
*/
rtctime = VRTC_BROKEN_TIME;
rtc->reg_b &= ~RTCSB_UINTR;
}
error = vrtc_time_update(vrtc, rtctime, basetime);
KASSERT(error == 0, ("vrtc_time_update error %d", error));
}
/*
* Side effect of changes to the interrupt enable bits.
*/
if (changed & RTCSB_ALL_INTRS)
vrtc_set_reg_c(vrtc, vrtc->rtcdev.reg_c);
/*
* Change the callout frequency if it has changed.
*/
newfreq = vrtc_freq(vrtc);
if (newfreq != oldfreq)
vrtc_callout_reset(vrtc, newfreq);
else
vrtc_callout_check(vrtc, newfreq);
/*
* The side effect of bits that control the RTC date/time format
* is handled lazily when those fields are actually read.
*/
return (0);
}
static void
vrtc_set_reg_a(struct vrtc *vrtc, uint8_t newval)
{
sbintime_t oldfreq, newfreq;
uint8_t oldval, changed;
KASSERT(VRTC_LOCKED(vrtc), ("%s: vrtc not locked", __func__));
newval &= ~RTCSA_TUP;
oldval = vrtc->rtcdev.reg_a;
oldfreq = vrtc_freq(vrtc);
if (divider_enabled(oldval) && !divider_enabled(newval)) {
VM_CTR2(vrtc->vm, "RTC divider held in reset at %#lx/%#lx",
vrtc->base_rtctime, vrtc->base_uptime);
} else if (!divider_enabled(oldval) && divider_enabled(newval)) {
/*
* If the dividers are coming out of reset then update
* 'base_uptime' before this happens. This is done to
* maintain the illusion that the RTC date/time was frozen
* while the dividers were disabled.
*/
vrtc->base_uptime = sbinuptime();
VM_CTR2(vrtc->vm, "RTC divider out of reset at %#lx/%#lx",
vrtc->base_rtctime, vrtc->base_uptime);
} else {
/* NOTHING */
}
vrtc->rtcdev.reg_a = newval;
changed = oldval ^ newval;
if (changed) {
VM_CTR2(vrtc->vm, "RTC reg_a changed from %#x to %#x",
oldval, newval);
}
/*
* Side effect of changes to rate select and divider enable bits.
*/
newfreq = vrtc_freq(vrtc);
if (newfreq != oldfreq)
vrtc_callout_reset(vrtc, newfreq);
else
vrtc_callout_check(vrtc, newfreq);
}
int
vrtc_set_time(struct vm *vm, time_t secs)
{
struct vrtc *vrtc;
int error;
vrtc = vm_rtc(vm);
VRTC_LOCK(vrtc);
error = vrtc_time_update(vrtc, secs, sbinuptime());
VRTC_UNLOCK(vrtc);
if (error) {
VM_CTR2(vrtc->vm, "Error %d setting RTC time to %#lx", error,
secs);
} else {
VM_CTR1(vrtc->vm, "RTC time set to %#lx", secs);
}
return (error);
}
time_t
vrtc_get_time(struct vm *vm)
{
struct vrtc *vrtc;
sbintime_t basetime;
time_t t;
vrtc = vm_rtc(vm);
VRTC_LOCK(vrtc);
t = vrtc_curtime(vrtc, &basetime);
VRTC_UNLOCK(vrtc);
return (t);
}
int
vrtc_nvram_write(struct vm *vm, int offset, uint8_t value)
{
struct vrtc *vrtc;
uint8_t *ptr;
vrtc = vm_rtc(vm);
/*
* Don't allow writes to RTC control registers or the date/time fields.
*/
if (offset < offsetof(struct rtcdev, nvram[0]) ||
offset == RTC_CENTURY || offset >= sizeof(struct rtcdev)) {
VM_CTR1(vrtc->vm, "RTC nvram write to invalid offset %d",
offset);
return (EINVAL);
}
VRTC_LOCK(vrtc);
ptr = (uint8_t *)(&vrtc->rtcdev);
ptr[offset] = value;
VM_CTR2(vrtc->vm, "RTC nvram write %#x to offset %#x", value, offset);
VRTC_UNLOCK(vrtc);
return (0);
}
int
vrtc_nvram_read(struct vm *vm, int offset, uint8_t *retval)
{
struct vrtc *vrtc;
sbintime_t basetime;
time_t curtime;
uint8_t *ptr;
/*
* Allow all offsets in the RTC to be read.
*/
if (offset < 0 || offset >= sizeof(struct rtcdev))
return (EINVAL);
vrtc = vm_rtc(vm);
VRTC_LOCK(vrtc);
/*
* Update RTC date/time fields if necessary.
*/
if (offset < 10 || offset == RTC_CENTURY) {
curtime = vrtc_curtime(vrtc, &basetime);
secs_to_rtc(curtime, vrtc, 0);
}
ptr = (uint8_t *)(&vrtc->rtcdev);
*retval = ptr[offset];
VRTC_UNLOCK(vrtc);
return (0);
}
int
vrtc_addr_handler(struct vm *vm, bool in, int port, int bytes, uint32_t *val)
{
struct vrtc *vrtc;
vrtc = vm_rtc(vm);
if (bytes != 1)
return (-1);
if (in) {
*val = 0xff;
return (0);
}
VRTC_LOCK(vrtc);
vrtc->addr = *val & 0x7f;
VRTC_UNLOCK(vrtc);
return (0);
}
int
vrtc_data_handler(struct vm *vm, bool in, int port, int bytes, uint32_t *val)
{
struct vrtc *vrtc;
struct rtcdev *rtc;
sbintime_t basetime;
time_t curtime;
int error, offset;
vrtc = vm_rtc(vm);
rtc = &vrtc->rtcdev;
if (bytes != 1)
return (-1);
VRTC_LOCK(vrtc);
offset = vrtc->addr;
if (offset >= sizeof(struct rtcdev)) {
VRTC_UNLOCK(vrtc);
return (-1);
}
error = 0;
curtime = vrtc_curtime(vrtc, &basetime);
vrtc_time_update(vrtc, curtime, basetime);
/*
* Update RTC date/time fields if necessary.
*
* This is not just for reads of the RTC. The side-effect of writing
* the century byte requires other RTC date/time fields (e.g. sec)
* to be updated here.
*/
if (offset < 10 || offset == RTC_CENTURY)
secs_to_rtc(curtime, vrtc, 0);
if (in) {
if (offset == 12) {
/*
* XXX
* reg_c interrupt flags are updated only if the
* corresponding interrupt enable bit in reg_b is set.
*/
*val = vrtc->rtcdev.reg_c;
vrtc_set_reg_c(vrtc, 0);
} else {
*val = *((uint8_t *)rtc + offset);
}
VM_CTR2(vm, "Read value %#x from RTC offset %#x",
*val, offset);
} else {
switch (offset) {
case 10:
VM_CTR1(vm, "RTC reg_a set to %#x", *val);
vrtc_set_reg_a(vrtc, *val);
break;
case 11:
VM_CTR1(vm, "RTC reg_b set to %#x", *val);
error = vrtc_set_reg_b(vrtc, *val);
break;
case 12:
VM_CTR1(vm, "RTC reg_c set to %#x (ignored)",
*val);
break;
case 13:
VM_CTR1(vm, "RTC reg_d set to %#x (ignored)",
*val);
break;
case 0:
/*
* High order bit of 'seconds' is readonly.
*/
*val &= 0x7f;
/* FALLTHRU */
default:
VM_CTR2(vm, "RTC offset %#x set to %#x",
offset, *val);
*((uint8_t *)rtc + offset) = *val;
break;
}
/*
* XXX some guests (e.g. OpenBSD) write the century byte
* outside of RTCSB_HALT so re-calculate the RTC date/time.
*/
if (offset == RTC_CENTURY && !rtc_halted(vrtc)) {
curtime = rtc_to_secs(vrtc);
error = vrtc_time_update(vrtc, curtime, sbinuptime());
KASSERT(!error, ("vrtc_time_update error %d", error));
if (curtime == VRTC_BROKEN_TIME && rtc_flag_broken_time)
error = -1;
}
}
VRTC_UNLOCK(vrtc);
return (error);
}
void
vrtc_reset(struct vrtc *vrtc)
{
struct rtcdev *rtc;
VRTC_LOCK(vrtc);
rtc = &vrtc->rtcdev;
vrtc_set_reg_b(vrtc, rtc->reg_b & ~(RTCSB_ALL_INTRS | RTCSB_SQWE));
vrtc_set_reg_c(vrtc, 0);
KASSERT(!callout_active(&vrtc->callout), ("rtc callout still active"));
VRTC_UNLOCK(vrtc);
}
struct vrtc *
vrtc_init(struct vm *vm)
{
struct vrtc *vrtc;
struct rtcdev *rtc;
time_t curtime;
vrtc = malloc(sizeof(struct vrtc), M_VRTC, M_WAITOK | M_ZERO);
vrtc->vm = vm;
mtx_init(&vrtc->mtx, "vrtc lock", NULL, MTX_DEF);
callout_init(&vrtc->callout, 1);
/* Allow dividers to keep time but disable everything else */
rtc = &vrtc->rtcdev;
rtc->reg_a = 0x20;
rtc->reg_b = RTCSB_24HR;
rtc->reg_c = 0;
rtc->reg_d = RTCSD_PWR;
/* Reset the index register to a safe value. */
vrtc->addr = RTC_STATUSD;
/*
* Initialize RTC time to 00:00:00 Jan 1, 1970.
*/
curtime = 0;
VRTC_LOCK(vrtc);
vrtc->base_rtctime = VRTC_BROKEN_TIME;
vrtc_time_update(vrtc, curtime, sbinuptime());
secs_to_rtc(curtime, vrtc, 0);
VRTC_UNLOCK(vrtc);
return (vrtc);
}
void
vrtc_cleanup(struct vrtc *vrtc)
{
callout_drain(&vrtc->callout);
mtx_destroy(&vrtc->mtx);
free(vrtc, M_VRTC);
}
#ifdef BHYVE_SNAPSHOT
int
vrtc_snapshot(struct vrtc *vrtc, struct vm_snapshot_meta *meta)
{
int ret;
VRTC_LOCK(vrtc);
SNAPSHOT_VAR_OR_LEAVE(vrtc->addr, meta, ret, done);
if (meta->op == VM_SNAPSHOT_RESTORE)
vrtc->base_uptime = sbinuptime();
SNAPSHOT_VAR_OR_LEAVE(vrtc->base_rtctime, meta, ret, done);
SNAPSHOT_VAR_OR_LEAVE(vrtc->rtcdev.sec, meta, ret, done);
SNAPSHOT_VAR_OR_LEAVE(vrtc->rtcdev.alarm_sec, meta, ret, done);
SNAPSHOT_VAR_OR_LEAVE(vrtc->rtcdev.min, meta, ret, done);
SNAPSHOT_VAR_OR_LEAVE(vrtc->rtcdev.alarm_min, meta, ret, done);
SNAPSHOT_VAR_OR_LEAVE(vrtc->rtcdev.hour, meta, ret, done);
SNAPSHOT_VAR_OR_LEAVE(vrtc->rtcdev.alarm_hour, meta, ret, done);
SNAPSHOT_VAR_OR_LEAVE(vrtc->rtcdev.day_of_week, meta, ret, done);
SNAPSHOT_VAR_OR_LEAVE(vrtc->rtcdev.day_of_month, meta, ret, done);
SNAPSHOT_VAR_OR_LEAVE(vrtc->rtcdev.month, meta, ret, done);
SNAPSHOT_VAR_OR_LEAVE(vrtc->rtcdev.year, meta, ret, done);
SNAPSHOT_VAR_OR_LEAVE(vrtc->rtcdev.reg_a, meta, ret, done);
SNAPSHOT_VAR_OR_LEAVE(vrtc->rtcdev.reg_b, meta, ret, done);
SNAPSHOT_VAR_OR_LEAVE(vrtc->rtcdev.reg_c, meta, ret, done);
SNAPSHOT_VAR_OR_LEAVE(vrtc->rtcdev.reg_d, meta, ret, done);
SNAPSHOT_BUF_OR_LEAVE(vrtc->rtcdev.nvram, sizeof(vrtc->rtcdev.nvram),
meta, ret, done);
SNAPSHOT_VAR_OR_LEAVE(vrtc->rtcdev.century, meta, ret, done);
SNAPSHOT_BUF_OR_LEAVE(vrtc->rtcdev.nvram2, sizeof(vrtc->rtcdev.nvram2),
meta, ret, done);
vrtc_callout_reset(vrtc, vrtc_freq(vrtc));
VRTC_UNLOCK(vrtc);
done:
return (ret);
}
#endif
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