Zhang, Yang Z
2012-Mar-08 00:43 UTC
[PATCH RESEND 1/5] RTC: use offset to caculate rtc clock
There has no need to run two periodic timer to update RTC time.
Use the offset instead.
Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
diff -r 33659563f589 -r f2e4c1af3759 xen/arch/x86/hvm/rtc.c
--- a/xen/arch/x86/hvm/rtc.c Fri Mar 02 12:33:25 2012 +0000
+++ b/xen/arch/x86/hvm/rtc.c Mon Mar 05 14:38:20 2012 +0800
@@ -36,6 +36,8 @@
#define epoch_year 1900
#define get_year(x) (x + epoch_year)
+static void rtc_copy_date(RTCState *s);
+
static void rtc_periodic_cb(struct vcpu *v, void *opaque) {
RTCState *s = opaque;
@@ -75,6 +77,7 @@ static void rtc_set_time(RTCState *s); static int
rtc_ioport_write(void *opaque, uint32_t addr, uint32_t data) {
RTCState *s = opaque;
+ struct domain *d = vrtc_domain(s);
spin_lock(&s->lock);
@@ -122,6 +125,12 @@ static int rtc_ioport_write(void *opaque
{
/* set mode: reset UIP mode */
s->hw.cmos_data[RTC_REG_A] &= ~RTC_UIP;
+ /* adjust cmos before stopping */
+ if (!(s->hw.cmos_data[RTC_REG_B] & RTC_SET))
+ {
+ s->current_tm = gmtime(get_localtime(d));
+ rtc_copy_date(s);
+ }
}
else
{
@@ -218,156 +227,10 @@ static void rtc_copy_date(RTCState *s)
s->hw.cmos_data[RTC_YEAR] = to_bcd(s, tm->tm_year % 100); }
-/* month is between 0 and 11. */
-static int get_days_in_month(int month, int year) -{
- static const int days_tab[12] = {
- 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
- };
- int d;
- if ( (unsigned)month >= 12 )
- return 31;
- d = days_tab[month];
- if ( month == 1 )
- if ( (year % 4) == 0 && ((year % 100) != 0 || (year % 400) ==
0) )
- d++;
- return d;
-}
-
-/* update ''tm'' to the next second */
-static void rtc_next_second(RTCState *s) -{
- struct tm *tm = &s->current_tm;
- int days_in_month;
-
- ASSERT(spin_is_locked(&s->lock));
-
- tm->tm_sec++;
- if ( (unsigned)tm->tm_sec >= 60 )
- {
- tm->tm_sec = 0;
- tm->tm_min++;
- if ( (unsigned)tm->tm_min >= 60 )
- {
- tm->tm_min = 0;
- tm->tm_hour++;
- if ( (unsigned)tm->tm_hour >= 24 )
- {
- tm->tm_hour = 0;
- /* next day */
- tm->tm_wday++;
- if ( (unsigned)tm->tm_wday >= 7 )
- tm->tm_wday = 0;
- days_in_month = get_days_in_month(tm->tm_mon,
- get_year(tm->tm_year));
- tm->tm_mday++;
- if ( tm->tm_mday < 1 )
- {
- tm->tm_mday = 1;
- }
- else if ( tm->tm_mday > days_in_month )
- {
- tm->tm_mday = 1;
- tm->tm_mon++;
- if ( tm->tm_mon >= 12 )
- {
- tm->tm_mon = 0;
- tm->tm_year++;
- }
- }
- }
- }
- }
-}
-
-static void rtc_update_second(void *opaque) -{
- RTCState *s = opaque;
- s_time_t now = NOW();
-
- spin_lock(&s->lock);
-
- /* If we somehow get way out of sync (say, Xen time leaps forward),
- * don''t livelock the system trying to emulate every second. Time
- * is already in bad trouble, so just skip forward rather than
- * trying to sync the RTC registers */
- if ( unlikely(now - s->next_second_time > SECONDS(86400)) )
- {
- dprintk(XENLOG_WARNING, "HVM RTC: dom %u skipping
%"PRId64" seconds\n",
- vrtc_domain(s)->domain_id,
- (int64_t)((now - s->next_second_time) / SYSTEM_TIME_HZ));
- s->next_second_time = now;
- }
-
- /* if the oscillator is not in normal operation, we do not update */
- if ( (s->hw.cmos_data[RTC_REG_A] & RTC_DIV_CTL) !=
RTC_REF_CLCK_32KHZ )
- {
- s->next_second_time += 1000000000ULL;
- set_timer(&s->second_timer, s->next_second_time);
- }
- else
- {
- rtc_next_second(s);
-
- if ( !(s->hw.cmos_data[RTC_REG_B] & RTC_SET) )
- s->hw.cmos_data[RTC_REG_A] |= RTC_UIP;
-
- /* Delay time before update cycle */
- set_timer(&s->second_timer2, s->next_second_time + 244000);
- }
-
- spin_unlock(&s->lock);
-}
-
-static void rtc_update_second2(void *opaque) -{
- RTCState *s = opaque;
- struct domain *d = vrtc_domain(s);
-
- spin_lock(&s->lock);
-
- if ( !(s->hw.cmos_data[RTC_REG_B] & RTC_SET) )
- rtc_copy_date(s);
-
- /* check alarm */
- if ( s->hw.cmos_data[RTC_REG_B] & RTC_AIE )
- {
- if ( ((s->hw.cmos_data[RTC_SECONDS_ALARM] & 0xc0) == 0xc0 ||
- from_bcd(s, s->hw.cmos_data[RTC_SECONDS_ALARM]) =-
s->current_tm.tm_sec) &&
- ((s->hw.cmos_data[RTC_MINUTES_ALARM] & 0xc0) == 0xc0 ||
- from_bcd(s, s->hw.cmos_data[RTC_MINUTES_ALARM]) =-
s->current_tm.tm_min) &&
- ((s->hw.cmos_data[RTC_HOURS_ALARM] & 0xc0) == 0xc0 ||
- from_bcd(s, s->hw.cmos_data[RTC_HOURS_ALARM]) =-
s->current_tm.tm_hour) )
- {
- s->hw.cmos_data[RTC_REG_C] |= 0xa0;
- hvm_isa_irq_deassert(d, RTC_IRQ);
- hvm_isa_irq_assert(d, RTC_IRQ);
- }
- }
-
- /* update ended interrupt */
- if ( (s->hw.cmos_data[RTC_REG_B] & (RTC_UIE|RTC_SET)) == RTC_UIE )
- {
- s->hw.cmos_data[RTC_REG_C] |= 0x90;
- hvm_isa_irq_deassert(d, RTC_IRQ);
- hvm_isa_irq_assert(d, RTC_IRQ);
- }
-
- /* clear update in progress bit */
- s->hw.cmos_data[RTC_REG_A] &= ~RTC_UIP;
-
- s->next_second_time += 1000000000ULL;
- set_timer(&s->second_timer, s->next_second_time);
-
- spin_unlock(&s->lock);
-}
-
static uint32_t rtc_ioport_read(RTCState *s, uint32_t addr) {
int ret;
+ struct domain *d = vrtc_domain(s);
if ( (addr & 1) == 0 )
return 0xff;
@@ -383,6 +246,12 @@ static uint32_t rtc_ioport_read(RTCState
case RTC_DAY_OF_MONTH:
case RTC_MONTH:
case RTC_YEAR:
+ /* if not in set mode, adjust cmos before reading*/
+ if (!(s->hw.cmos_data[RTC_REG_B] & RTC_SET))
+ {
+ s->current_tm = gmtime(get_localtime(d));
+ rtc_copy_date(s);
+ }
ret = s->hw.cmos_data[s->hw.cmos_index];
break;
case RTC_REG_A:
@@ -430,12 +299,9 @@ static int handle_rtc_io(
void rtc_migrate_timers(struct vcpu *v) {
- RTCState *s = vcpu_vrtc(v);
-
if ( v->vcpu_id == 0 )
{
- migrate_timer(&s->second_timer, v->processor);
- migrate_timer(&s->second_timer2, v->processor);
+ ;
}
}
@@ -468,9 +334,6 @@ static int rtc_load(struct domain *d, hv
* time, so let''s keep doing that. */
s->current_tm = gmtime(get_localtime(d));
rtc_copy_date(s);
- s->next_second_time = NOW() + 1000000000ULL;
- stop_timer(&s->second_timer);
- set_timer(&s->second_timer2, s->next_second_time);
/* Reset the periodic interrupt timer based on the registers */
rtc_timer_update(s);
@@ -496,9 +359,6 @@ void rtc_init(struct domain *d)
spin_lock_init(&s->lock);
- init_timer(&s->second_timer, rtc_update_second, s,
smp_processor_id());
- init_timer(&s->second_timer2, rtc_update_second2, s,
smp_processor_id());
-
register_portio_handler(d, RTC_PORT(0), 2, handle_rtc_io);
rtc_reset(d);
@@ -514,10 +374,6 @@ void rtc_init(struct domain *d)
rtc_copy_date(s);
- s->next_second_time = NOW() + 1000000000ULL;
- stop_timer(&s->second_timer);
- set_timer(&s->second_timer2, s->next_second_time);
-
spin_unlock(&s->lock);
}
@@ -528,8 +384,6 @@ void rtc_deinit(struct domain *d)
spin_barrier(&s->lock);
destroy_periodic_time(&s->pt);
- kill_timer(&s->second_timer);
- kill_timer(&s->second_timer2);
}
void rtc_update_clock(struct domain *d) diff -r 33659563f589 -r f2e4c1af3759
xen/include/asm-x86/hvm/vpt.h
--- a/xen/include/asm-x86/hvm/vpt.h Fri Mar 02 12:33:25 2012 +0000
+++ b/xen/include/asm-x86/hvm/vpt.h Mon Mar 05 14:38:20 2012 +0800
@@ -106,8 +106,6 @@ typedef struct RTCState {
struct tm current_tm;
/* second update */
int64_t next_second_time;
- struct timer second_timer;
- struct timer second_timer2;
struct periodic_time pt;
spinlock_t lock;
} RTCState;