qemu-patch-raspberry4/hw/mc146818rtc.c
Yang Zhang 56038ef623 RTC: Update the RTC clock only when reading it
Calculate guest RTC based on the time of the last update, instead of
using timers.  The formula is

    (base_rtc + guest_time_now - guest_time_last_update + offset)

Base_rtc is the RTC value when the RTC was last updated.
Guest_time_now is the guest time when the access happens.
Guest_time_last_update was the guest time when the RTC was last updated.
Offset is used when divider reset happens or the set bit is toggled.

The timer is kept in order to signal interrupts, but it only needs to
run when either UF or AF is cleared.  When the bits are both set, the
timer does not run.

UIP is now synthesized when reading register A.  If the timer is not set,
or if there is more than one second before it (as is the case at the
end of this series), the leading edge of UIP is computed and the rising
edge occurs 220us later.  If the update timer occurs within one second,
however, the rising edge of the AF and UF bits should coincide withe
the falling edge of UIP.  We do not know exactly when this will happen
because there could be delays in the servicing of the timer.  Hence, in
this case reading register A only computes for the rising edge of UIP,
and latches the bit until the timer is fired and clears it.

Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-09-10 13:52:28 -05:00

777 lines
24 KiB
C

/*
* QEMU MC146818 RTC emulation
*
* Copyright (c) 2003-2004 Fabrice Bellard
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "hw.h"
#include "qemu-timer.h"
#include "sysemu.h"
#include "mc146818rtc.h"
#ifdef TARGET_I386
#include "apic.h"
#endif
//#define DEBUG_CMOS
//#define DEBUG_COALESCED
#ifdef DEBUG_CMOS
# define CMOS_DPRINTF(format, ...) printf(format, ## __VA_ARGS__)
#else
# define CMOS_DPRINTF(format, ...) do { } while (0)
#endif
#ifdef DEBUG_COALESCED
# define DPRINTF_C(format, ...) printf(format, ## __VA_ARGS__)
#else
# define DPRINTF_C(format, ...) do { } while (0)
#endif
#define NSEC_PER_SEC 1000000000LL
#define RTC_REINJECT_ON_ACK_COUNT 20
#define RTC_CLOCK_RATE 32768
#define UIP_HOLD_LENGTH (8 * NSEC_PER_SEC / 32768)
typedef struct RTCState {
ISADevice dev;
MemoryRegion io;
uint8_t cmos_data[128];
uint8_t cmos_index;
struct tm current_tm;
int32_t base_year;
uint64_t base_rtc;
uint64_t last_update;
int64_t offset;
qemu_irq irq;
qemu_irq sqw_irq;
int it_shift;
/* periodic timer */
QEMUTimer *periodic_timer;
int64_t next_periodic_time;
/* update-ended timer */
QEMUTimer *update_timer;
uint16_t irq_reinject_on_ack_count;
uint32_t irq_coalesced;
uint32_t period;
QEMUTimer *coalesced_timer;
Notifier clock_reset_notifier;
LostTickPolicy lost_tick_policy;
Notifier suspend_notifier;
} RTCState;
static void rtc_set_time(RTCState *s);
static void rtc_update_time(RTCState *s);
static void rtc_set_cmos(RTCState *s);
static inline int rtc_from_bcd(RTCState *s, int a);
static uint64_t get_guest_rtc_ns(RTCState *s)
{
uint64_t guest_rtc;
uint64_t guest_clock = qemu_get_clock_ns(rtc_clock);
guest_rtc = s->base_rtc * NSEC_PER_SEC
+ guest_clock - s->last_update + s->offset;
return guest_rtc;
}
#ifdef TARGET_I386
static void rtc_coalesced_timer_update(RTCState *s)
{
if (s->irq_coalesced == 0) {
qemu_del_timer(s->coalesced_timer);
} else {
/* divide each RTC interval to 2 - 8 smaller intervals */
int c = MIN(s->irq_coalesced, 7) + 1;
int64_t next_clock = qemu_get_clock_ns(rtc_clock) +
muldiv64(s->period / c, get_ticks_per_sec(), RTC_CLOCK_RATE);
qemu_mod_timer(s->coalesced_timer, next_clock);
}
}
static void rtc_coalesced_timer(void *opaque)
{
RTCState *s = opaque;
if (s->irq_coalesced != 0) {
apic_reset_irq_delivered();
s->cmos_data[RTC_REG_C] |= 0xc0;
DPRINTF_C("cmos: injecting from timer\n");
qemu_irq_raise(s->irq);
if (apic_get_irq_delivered()) {
s->irq_coalesced--;
DPRINTF_C("cmos: coalesced irqs decreased to %d\n",
s->irq_coalesced);
}
}
rtc_coalesced_timer_update(s);
}
#endif
/* handle periodic timer */
static void periodic_timer_update(RTCState *s, int64_t current_time)
{
int period_code, period;
int64_t cur_clock, next_irq_clock;
period_code = s->cmos_data[RTC_REG_A] & 0x0f;
if (period_code != 0
&& ((s->cmos_data[RTC_REG_B] & REG_B_PIE)
|| ((s->cmos_data[RTC_REG_B] & REG_B_SQWE) && s->sqw_irq))) {
if (period_code <= 2)
period_code += 7;
/* period in 32 Khz cycles */
period = 1 << (period_code - 1);
#ifdef TARGET_I386
if (period != s->period) {
s->irq_coalesced = (s->irq_coalesced * s->period) / period;
DPRINTF_C("cmos: coalesced irqs scaled to %d\n", s->irq_coalesced);
}
s->period = period;
#endif
/* compute 32 khz clock */
cur_clock = muldiv64(current_time, RTC_CLOCK_RATE, get_ticks_per_sec());
next_irq_clock = (cur_clock & ~(period - 1)) + period;
s->next_periodic_time =
muldiv64(next_irq_clock, get_ticks_per_sec(), RTC_CLOCK_RATE) + 1;
qemu_mod_timer(s->periodic_timer, s->next_periodic_time);
} else {
#ifdef TARGET_I386
s->irq_coalesced = 0;
#endif
qemu_del_timer(s->periodic_timer);
}
}
static void rtc_periodic_timer(void *opaque)
{
RTCState *s = opaque;
periodic_timer_update(s, s->next_periodic_time);
s->cmos_data[RTC_REG_C] |= REG_C_PF;
if (s->cmos_data[RTC_REG_B] & REG_B_PIE) {
s->cmos_data[RTC_REG_C] |= REG_C_IRQF;
#ifdef TARGET_I386
if (s->lost_tick_policy == LOST_TICK_SLEW) {
if (s->irq_reinject_on_ack_count >= RTC_REINJECT_ON_ACK_COUNT)
s->irq_reinject_on_ack_count = 0;
apic_reset_irq_delivered();
qemu_irq_raise(s->irq);
if (!apic_get_irq_delivered()) {
s->irq_coalesced++;
rtc_coalesced_timer_update(s);
DPRINTF_C("cmos: coalesced irqs increased to %d\n",
s->irq_coalesced);
}
} else
#endif
qemu_irq_raise(s->irq);
}
if (s->cmos_data[RTC_REG_B] & REG_B_SQWE) {
/* Not square wave at all but we don't want 2048Hz interrupts!
Must be seen as a pulse. */
qemu_irq_raise(s->sqw_irq);
}
}
/* handle update-ended timer */
static void check_update_timer(RTCState *s)
{
uint64_t next_update_time;
uint64_t guest_nsec;
/* From the data sheet: setting the SET bit does not prevent
* interrupts from occurring! However, it will prevent an
* alarm interrupt from occurring, because the time of day is
* not updated.
*/
if ((s->cmos_data[RTC_REG_C] & REG_C_UF) &&
(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
qemu_del_timer(s->update_timer);
return;
}
if ((s->cmos_data[RTC_REG_C] & REG_C_UF) &&
(s->cmos_data[RTC_REG_C] & REG_C_AF)) {
qemu_del_timer(s->update_timer);
return;
}
guest_nsec = get_guest_rtc_ns(s) % NSEC_PER_SEC;
/* reprogram to next second */
next_update_time = qemu_get_clock_ns(rtc_clock)
+ NSEC_PER_SEC - guest_nsec;
if (next_update_time != qemu_timer_expire_time_ns(s->update_timer)) {
qemu_mod_timer(s->update_timer, next_update_time);
}
}
static inline uint8_t convert_hour(RTCState *s, uint8_t hour)
{
if (!(s->cmos_data[RTC_REG_B] & REG_B_24H)) {
hour %= 12;
if (s->cmos_data[RTC_HOURS] & 0x80) {
hour += 12;
}
}
return hour;
}
static uint32_t check_alarm(RTCState *s)
{
uint8_t alarm_hour, alarm_min, alarm_sec;
uint8_t cur_hour, cur_min, cur_sec;
alarm_sec = rtc_from_bcd(s, s->cmos_data[RTC_SECONDS_ALARM]);
alarm_min = rtc_from_bcd(s, s->cmos_data[RTC_MINUTES_ALARM]);
alarm_hour = rtc_from_bcd(s, s->cmos_data[RTC_HOURS_ALARM]);
alarm_hour = convert_hour(s, alarm_hour);
cur_sec = rtc_from_bcd(s, s->cmos_data[RTC_SECONDS]);
cur_min = rtc_from_bcd(s, s->cmos_data[RTC_MINUTES]);
cur_hour = rtc_from_bcd(s, s->cmos_data[RTC_HOURS]);
cur_hour = convert_hour(s, cur_hour);
if (((s->cmos_data[RTC_SECONDS_ALARM] & 0xc0) == 0xc0
|| alarm_sec == cur_sec) &&
((s->cmos_data[RTC_MINUTES_ALARM] & 0xc0) == 0xc0
|| alarm_min == cur_min) &&
((s->cmos_data[RTC_HOURS_ALARM] & 0xc0) == 0xc0
|| alarm_hour == cur_hour)) {
return 1;
}
return 0;
}
static void rtc_update_timer(void *opaque)
{
RTCState *s = opaque;
int32_t irqs = REG_C_UF;
int32_t new_irqs;
/* UIP might have been latched, update time and clear it. */
rtc_update_time(s);
s->cmos_data[RTC_REG_A] &= ~REG_A_UIP;
if (check_alarm(s)) {
irqs |= REG_C_AF;
if (s->cmos_data[RTC_REG_B] & REG_B_AIE) {
qemu_system_wakeup_request(QEMU_WAKEUP_REASON_RTC);
}
}
new_irqs = irqs & ~s->cmos_data[RTC_REG_C];
s->cmos_data[RTC_REG_C] |= irqs;
if ((new_irqs & s->cmos_data[RTC_REG_B]) != 0) {
s->cmos_data[RTC_REG_C] |= REG_C_IRQF;
qemu_irq_raise(s->irq);
}
check_update_timer(s);
}
static void cmos_ioport_write(void *opaque, uint32_t addr, uint32_t data)
{
RTCState *s = opaque;
if ((addr & 1) == 0) {
s->cmos_index = data & 0x7f;
} else {
CMOS_DPRINTF("cmos: write index=0x%02x val=0x%02x\n",
s->cmos_index, data);
switch(s->cmos_index) {
case RTC_SECONDS_ALARM:
case RTC_MINUTES_ALARM:
case RTC_HOURS_ALARM:
s->cmos_data[s->cmos_index] = data;
check_update_timer(s);
break;
case RTC_SECONDS:
case RTC_MINUTES:
case RTC_HOURS:
case RTC_DAY_OF_WEEK:
case RTC_DAY_OF_MONTH:
case RTC_MONTH:
case RTC_YEAR:
s->cmos_data[s->cmos_index] = data;
/* if in set mode, do not update the time */
if (!(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
rtc_set_time(s);
check_update_timer(s);
}
break;
case RTC_REG_A:
/* UIP bit is read only */
s->cmos_data[RTC_REG_A] = (data & ~REG_A_UIP) |
(s->cmos_data[RTC_REG_A] & REG_A_UIP);
periodic_timer_update(s, qemu_get_clock_ns(rtc_clock));
check_update_timer(s);
break;
case RTC_REG_B:
if (data & REG_B_SET) {
/* update cmos to when the rtc was stopping */
if (!(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
rtc_update_time(s);
}
/* set mode: reset UIP mode */
s->cmos_data[RTC_REG_A] &= ~REG_A_UIP;
data &= ~REG_B_UIE;
} else {
/* if disabling set mode, update the time */
if (s->cmos_data[RTC_REG_B] & REG_B_SET) {
s->offset = get_guest_rtc_ns(s) % NSEC_PER_SEC;
rtc_set_time(s);
}
}
/* if an interrupt flag is already set when the interrupt
* becomes enabled, raise an interrupt immediately. */
if (data & s->cmos_data[RTC_REG_C] & REG_C_MASK) {
s->cmos_data[RTC_REG_C] |= REG_C_IRQF;
qemu_irq_raise(s->irq);
} else {
s->cmos_data[RTC_REG_C] &= ~REG_C_IRQF;
qemu_irq_lower(s->irq);
}
s->cmos_data[RTC_REG_B] = data;
periodic_timer_update(s, qemu_get_clock_ns(rtc_clock));
check_update_timer(s);
break;
case RTC_REG_C:
case RTC_REG_D:
/* cannot write to them */
break;
default:
s->cmos_data[s->cmos_index] = data;
break;
}
}
}
static inline int rtc_to_bcd(RTCState *s, int a)
{
if (s->cmos_data[RTC_REG_B] & REG_B_DM) {
return a;
} else {
return ((a / 10) << 4) | (a % 10);
}
}
static inline int rtc_from_bcd(RTCState *s, int a)
{
if (s->cmos_data[RTC_REG_B] & REG_B_DM) {
return a;
} else {
return ((a >> 4) * 10) + (a & 0x0f);
}
}
static void rtc_set_time(RTCState *s)
{
struct tm *tm = &s->current_tm;
tm->tm_sec = rtc_from_bcd(s, s->cmos_data[RTC_SECONDS]);
tm->tm_min = rtc_from_bcd(s, s->cmos_data[RTC_MINUTES]);
tm->tm_hour = rtc_from_bcd(s, s->cmos_data[RTC_HOURS] & 0x7f);
if (!(s->cmos_data[RTC_REG_B] & REG_B_24H)) {
tm->tm_hour %= 12;
if (s->cmos_data[RTC_HOURS] & 0x80) {
tm->tm_hour += 12;
}
}
tm->tm_wday = rtc_from_bcd(s, s->cmos_data[RTC_DAY_OF_WEEK]) - 1;
tm->tm_mday = rtc_from_bcd(s, s->cmos_data[RTC_DAY_OF_MONTH]);
tm->tm_mon = rtc_from_bcd(s, s->cmos_data[RTC_MONTH]) - 1;
tm->tm_year = rtc_from_bcd(s, s->cmos_data[RTC_YEAR]) + s->base_year - 1900;
s->base_rtc = mktimegm(tm);
s->last_update = qemu_get_clock_ns(rtc_clock);
rtc_change_mon_event(tm);
}
static void rtc_set_cmos(RTCState *s)
{
const struct tm *tm = &s->current_tm;
int year;
s->cmos_data[RTC_SECONDS] = rtc_to_bcd(s, tm->tm_sec);
s->cmos_data[RTC_MINUTES] = rtc_to_bcd(s, tm->tm_min);
if (s->cmos_data[RTC_REG_B] & REG_B_24H) {
/* 24 hour format */
s->cmos_data[RTC_HOURS] = rtc_to_bcd(s, tm->tm_hour);
} else {
/* 12 hour format */
int h = (tm->tm_hour % 12) ? tm->tm_hour % 12 : 12;
s->cmos_data[RTC_HOURS] = rtc_to_bcd(s, h);
if (tm->tm_hour >= 12)
s->cmos_data[RTC_HOURS] |= 0x80;
}
s->cmos_data[RTC_DAY_OF_WEEK] = rtc_to_bcd(s, tm->tm_wday + 1);
s->cmos_data[RTC_DAY_OF_MONTH] = rtc_to_bcd(s, tm->tm_mday);
s->cmos_data[RTC_MONTH] = rtc_to_bcd(s, tm->tm_mon + 1);
year = (tm->tm_year - s->base_year) % 100;
if (year < 0)
year += 100;
s->cmos_data[RTC_YEAR] = rtc_to_bcd(s, year);
}
static void rtc_update_time(RTCState *s)
{
struct tm ret;
time_t guest_sec;
int64_t guest_nsec;
guest_nsec = get_guest_rtc_ns(s);
guest_sec = guest_nsec / NSEC_PER_SEC;
gmtime_r(&guest_sec, &ret);
s->current_tm = ret;
rtc_set_cmos(s);
}
static int update_in_progress(RTCState *s)
{
int64_t guest_nsec;
if (s->cmos_data[RTC_REG_B] & REG_B_SET) {
return 0;
}
if (qemu_timer_pending(s->update_timer)) {
int64_t next_update_time = qemu_timer_expire_time_ns(s->update_timer);
/* Latch UIP until the timer expires. */
if (qemu_get_clock_ns(rtc_clock) >= (next_update_time - UIP_HOLD_LENGTH)) {
s->cmos_data[RTC_REG_A] |= REG_A_UIP;
return 1;
}
}
guest_nsec = get_guest_rtc_ns(s);
/* UIP bit will be set at last 244us of every second. */
if ((guest_nsec % NSEC_PER_SEC) >= (NSEC_PER_SEC - UIP_HOLD_LENGTH)) {
return 1;
}
return 0;
}
static uint32_t cmos_ioport_read(void *opaque, uint32_t addr)
{
RTCState *s = opaque;
int ret;
if ((addr & 1) == 0) {
return 0xff;
} else {
switch(s->cmos_index) {
case RTC_SECONDS:
case RTC_MINUTES:
case RTC_HOURS:
case RTC_DAY_OF_WEEK:
case RTC_DAY_OF_MONTH:
case RTC_MONTH:
case RTC_YEAR:
/* if not in set mode, calibrate cmos before
* reading*/
if (!(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
rtc_update_time(s);
}
ret = s->cmos_data[s->cmos_index];
break;
case RTC_REG_A:
if (update_in_progress(s)) {
s->cmos_data[s->cmos_index] |= REG_A_UIP;
} else {
s->cmos_data[s->cmos_index] &= ~REG_A_UIP;
}
ret = s->cmos_data[s->cmos_index];
break;
case RTC_REG_C:
ret = s->cmos_data[s->cmos_index];
qemu_irq_lower(s->irq);
s->cmos_data[RTC_REG_C] = 0x00;
if (ret & (REG_C_UF | REG_C_AF)) {
check_update_timer(s);
}
#ifdef TARGET_I386
if(s->irq_coalesced &&
(s->cmos_data[RTC_REG_B] & REG_B_PIE) &&
s->irq_reinject_on_ack_count < RTC_REINJECT_ON_ACK_COUNT) {
s->irq_reinject_on_ack_count++;
s->cmos_data[RTC_REG_C] |= REG_C_IRQF | REG_C_PF;
apic_reset_irq_delivered();
DPRINTF_C("cmos: injecting on ack\n");
qemu_irq_raise(s->irq);
if (apic_get_irq_delivered()) {
s->irq_coalesced--;
DPRINTF_C("cmos: coalesced irqs decreased to %d\n",
s->irq_coalesced);
}
}
#endif
break;
default:
ret = s->cmos_data[s->cmos_index];
break;
}
CMOS_DPRINTF("cmos: read index=0x%02x val=0x%02x\n",
s->cmos_index, ret);
return ret;
}
}
void rtc_set_memory(ISADevice *dev, int addr, int val)
{
RTCState *s = DO_UPCAST(RTCState, dev, dev);
if (addr >= 0 && addr <= 127)
s->cmos_data[addr] = val;
}
/* PC cmos mappings */
#define REG_IBM_CENTURY_BYTE 0x32
#define REG_IBM_PS2_CENTURY_BYTE 0x37
static void rtc_set_date_from_host(ISADevice *dev)
{
RTCState *s = DO_UPCAST(RTCState, dev, dev);
struct tm tm;
int val;
qemu_get_timedate(&tm, 0);
s->base_rtc = mktimegm(&tm);
s->last_update = qemu_get_clock_ns(rtc_clock);
s->offset = 0;
/* set the CMOS date */
s->current_tm = tm;
rtc_set_cmos(s);
val = rtc_to_bcd(s, (tm.tm_year / 100) + 19);
rtc_set_memory(dev, REG_IBM_CENTURY_BYTE, val);
rtc_set_memory(dev, REG_IBM_PS2_CENTURY_BYTE, val);
}
static int rtc_post_load(void *opaque, int version_id)
{
RTCState *s = opaque;
if (version_id <= 2) {
rtc_set_time(s);
s->offset = 0;
check_update_timer(s);
}
#ifdef TARGET_I386
if (version_id >= 2) {
if (s->lost_tick_policy == LOST_TICK_SLEW) {
rtc_coalesced_timer_update(s);
}
}
#endif
return 0;
}
static const VMStateDescription vmstate_rtc = {
.name = "mc146818rtc",
.version_id = 3,
.minimum_version_id = 1,
.minimum_version_id_old = 1,
.post_load = rtc_post_load,
.fields = (VMStateField []) {
VMSTATE_BUFFER(cmos_data, RTCState),
VMSTATE_UINT8(cmos_index, RTCState),
VMSTATE_INT32(current_tm.tm_sec, RTCState),
VMSTATE_INT32(current_tm.tm_min, RTCState),
VMSTATE_INT32(current_tm.tm_hour, RTCState),
VMSTATE_INT32(current_tm.tm_wday, RTCState),
VMSTATE_INT32(current_tm.tm_mday, RTCState),
VMSTATE_INT32(current_tm.tm_mon, RTCState),
VMSTATE_INT32(current_tm.tm_year, RTCState),
VMSTATE_TIMER(periodic_timer, RTCState),
VMSTATE_INT64(next_periodic_time, RTCState),
VMSTATE_UNUSED(3*8),
VMSTATE_UINT32_V(irq_coalesced, RTCState, 2),
VMSTATE_UINT32_V(period, RTCState, 2),
VMSTATE_UINT64_V(base_rtc, RTCState, 3),
VMSTATE_UINT64_V(last_update, RTCState, 3),
VMSTATE_INT64_V(offset, RTCState, 3),
VMSTATE_TIMER_V(update_timer, RTCState, 3),
VMSTATE_END_OF_LIST()
}
};
static void rtc_notify_clock_reset(Notifier *notifier, void *data)
{
RTCState *s = container_of(notifier, RTCState, clock_reset_notifier);
int64_t now = *(int64_t *)data;
rtc_set_date_from_host(&s->dev);
periodic_timer_update(s, now);
check_update_timer(s);
#ifdef TARGET_I386
if (s->lost_tick_policy == LOST_TICK_SLEW) {
rtc_coalesced_timer_update(s);
}
#endif
}
/* set CMOS shutdown status register (index 0xF) as S3_resume(0xFE)
BIOS will read it and start S3 resume at POST Entry */
static void rtc_notify_suspend(Notifier *notifier, void *data)
{
RTCState *s = container_of(notifier, RTCState, suspend_notifier);
rtc_set_memory(&s->dev, 0xF, 0xFE);
}
static void rtc_reset(void *opaque)
{
RTCState *s = opaque;
s->cmos_data[RTC_REG_B] &= ~(REG_B_PIE | REG_B_AIE | REG_B_SQWE);
s->cmos_data[RTC_REG_C] &= ~(REG_C_UF | REG_C_IRQF | REG_C_PF | REG_C_AF);
check_update_timer(s);
qemu_irq_lower(s->irq);
#ifdef TARGET_I386
if (s->lost_tick_policy == LOST_TICK_SLEW) {
s->irq_coalesced = 0;
}
#endif
}
static const MemoryRegionPortio cmos_portio[] = {
{0, 2, 1, .read = cmos_ioport_read, .write = cmos_ioport_write },
PORTIO_END_OF_LIST(),
};
static const MemoryRegionOps cmos_ops = {
.old_portio = cmos_portio
};
static void rtc_get_date(Object *obj, Visitor *v, void *opaque,
const char *name, Error **errp)
{
ISADevice *isa = ISA_DEVICE(obj);
RTCState *s = DO_UPCAST(RTCState, dev, isa);
rtc_update_time(s);
visit_start_struct(v, NULL, "struct tm", name, 0, errp);
visit_type_int32(v, &s->current_tm.tm_year, "tm_year", errp);
visit_type_int32(v, &s->current_tm.tm_mon, "tm_mon", errp);
visit_type_int32(v, &s->current_tm.tm_mday, "tm_mday", errp);
visit_type_int32(v, &s->current_tm.tm_hour, "tm_hour", errp);
visit_type_int32(v, &s->current_tm.tm_min, "tm_min", errp);
visit_type_int32(v, &s->current_tm.tm_sec, "tm_sec", errp);
visit_end_struct(v, errp);
}
static int rtc_initfn(ISADevice *dev)
{
RTCState *s = DO_UPCAST(RTCState, dev, dev);
int base = 0x70;
s->cmos_data[RTC_REG_A] = 0x26;
s->cmos_data[RTC_REG_B] = 0x02;
s->cmos_data[RTC_REG_C] = 0x00;
s->cmos_data[RTC_REG_D] = 0x80;
rtc_set_date_from_host(dev);
#ifdef TARGET_I386
switch (s->lost_tick_policy) {
case LOST_TICK_SLEW:
s->coalesced_timer =
qemu_new_timer_ns(rtc_clock, rtc_coalesced_timer, s);
break;
case LOST_TICK_DISCARD:
break;
default:
return -EINVAL;
}
#endif
s->periodic_timer = qemu_new_timer_ns(rtc_clock, rtc_periodic_timer, s);
s->update_timer = qemu_new_timer_ns(rtc_clock, rtc_update_timer, s);
check_update_timer(s);
s->clock_reset_notifier.notify = rtc_notify_clock_reset;
qemu_register_clock_reset_notifier(rtc_clock, &s->clock_reset_notifier);
s->suspend_notifier.notify = rtc_notify_suspend;
qemu_register_suspend_notifier(&s->suspend_notifier);
memory_region_init_io(&s->io, &cmos_ops, s, "rtc", 2);
isa_register_ioport(dev, &s->io, base);
qdev_set_legacy_instance_id(&dev->qdev, base, 3);
qemu_register_reset(rtc_reset, s);
object_property_add(OBJECT(s), "date", "struct tm",
rtc_get_date, NULL, NULL, s, NULL);
return 0;
}
ISADevice *rtc_init(ISABus *bus, int base_year, qemu_irq intercept_irq)
{
ISADevice *dev;
RTCState *s;
dev = isa_create(bus, "mc146818rtc");
s = DO_UPCAST(RTCState, dev, dev);
qdev_prop_set_int32(&dev->qdev, "base_year", base_year);
qdev_init_nofail(&dev->qdev);
if (intercept_irq) {
s->irq = intercept_irq;
} else {
isa_init_irq(dev, &s->irq, RTC_ISA_IRQ);
}
return dev;
}
static Property mc146818rtc_properties[] = {
DEFINE_PROP_INT32("base_year", RTCState, base_year, 1980),
DEFINE_PROP_LOSTTICKPOLICY("lost_tick_policy", RTCState,
lost_tick_policy, LOST_TICK_DISCARD),
DEFINE_PROP_END_OF_LIST(),
};
static void rtc_class_initfn(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
ISADeviceClass *ic = ISA_DEVICE_CLASS(klass);
ic->init = rtc_initfn;
dc->no_user = 1;
dc->vmsd = &vmstate_rtc;
dc->props = mc146818rtc_properties;
}
static TypeInfo mc146818rtc_info = {
.name = "mc146818rtc",
.parent = TYPE_ISA_DEVICE,
.instance_size = sizeof(RTCState),
.class_init = rtc_class_initfn,
};
static void mc146818rtc_register_types(void)
{
type_register_static(&mc146818rtc_info);
}
type_init(mc146818rtc_register_types)