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-rw-r--r--hw/mc146818rtc.c298
1 files changed, 264 insertions, 34 deletions
diff --git a/hw/mc146818rtc.c b/hw/mc146818rtc.c
index 7d94b25f56..4505fc9586 100644
--- a/hw/mc146818rtc.c
+++ b/hw/mc146818rtc.c
@@ -63,11 +63,62 @@
#define RTC_REG_C 12
#define RTC_REG_D 13
-/* PC cmos mappings */
-#define REG_IBM_CENTURY_BYTE 0x32
-#define REG_IBM_PS2_CENTURY_BYTE 0x37
+#define REG_A_UIP 0x80
-RTCState rtc_state;
+#define REG_B_SET 0x80
+#define REG_B_PIE 0x40
+#define REG_B_AIE 0x20
+#define REG_B_UIE 0x10
+
+struct RTCState {
+ uint8_t cmos_data[128];
+ uint8_t cmos_index;
+ int current_time; /* in seconds */
+ int irq;
+ uint8_t buf_data[10]; /* buffered data */
+ /* periodic timer */
+ QEMUTimer *periodic_timer;
+ int64_t next_periodic_time;
+ /* second update */
+ int64_t next_second_time;
+ QEMUTimer *second_timer;
+ QEMUTimer *second_timer2;
+};
+
+static void rtc_set_time(RTCState *s);
+static void rtc_set_date_buf(RTCState *s, const struct tm *tm);
+static void rtc_copy_date(RTCState *s);
+
+static void rtc_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)) {
+ if (period_code <= 2)
+ period_code += 7;
+ /* period in 32 Khz cycles */
+ period = 1 << (period_code - 1);
+ /* compute 32 khz clock */
+ cur_clock = muldiv64(current_time, 32768, ticks_per_sec);
+ next_irq_clock = (cur_clock & ~(period - 1)) + period;
+ s->next_periodic_time = muldiv64(next_irq_clock, ticks_per_sec, 32768) + 1;
+ qemu_mod_timer(s->periodic_timer, s->next_periodic_time);
+ } else {
+ qemu_del_timer(s->periodic_timer);
+ }
+}
+
+static void rtc_periodic_timer(void *opaque)
+{
+ RTCState *s = opaque;
+
+ rtc_timer_update(s, s->next_periodic_time);
+ s->cmos_data[RTC_REG_C] |= 0xc0;
+ pic_set_irq(s->irq, 1);
+}
static void cmos_ioport_write(void *opaque, uint32_t addr, uint32_t data)
{
@@ -80,7 +131,7 @@ static void cmos_ioport_write(void *opaque, uint32_t addr, uint32_t data)
printf("cmos: write index=0x%02x val=0x%02x\n",
s->cmos_index, data);
#endif
- switch(addr) {
+ switch(s->cmos_index) {
case RTC_SECONDS_ALARM:
case RTC_MINUTES_ALARM:
case RTC_HOURS_ALARM:
@@ -95,10 +146,30 @@ static void cmos_ioport_write(void *opaque, uint32_t addr, uint32_t data)
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);
+ }
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);
+ rtc_timer_update(s, qemu_get_clock(vm_clock));
+ break;
case RTC_REG_B:
- s->cmos_data[s->cmos_index] = data;
+ if (data & REG_B_SET) {
+ /* 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) {
+ rtc_set_time(s);
+ }
+ }
+ s->cmos_data[RTC_REG_B] = data;
+ rtc_timer_update(s, qemu_get_clock(vm_clock));
break;
case RTC_REG_C:
case RTC_REG_D:
@@ -111,27 +182,104 @@ static void cmos_ioport_write(void *opaque, uint32_t addr, uint32_t data)
}
}
-static inline int to_bcd(int a)
+static inline int to_bcd(RTCState *s, int a)
{
- return ((a / 10) << 4) | (a % 10);
+ if (s->cmos_data[RTC_REG_B] & 0x04) {
+ return a;
+ } else {
+ return ((a / 10) << 4) | (a % 10);
+ }
}
-static void cmos_update_time(RTCState *s)
+static inline int from_bcd(RTCState *s, int a)
{
- struct tm *tm;
+ if (s->cmos_data[RTC_REG_B] & 0x04) {
+ return a;
+ } else {
+ return ((a >> 4) * 10) + (a & 0x0f);
+ }
+}
+
+static void rtc_set_time(RTCState *s)
+{
+ struct tm tm1, *tm = &tm1;
+
+ tm->tm_sec = from_bcd(s, s->cmos_data[RTC_SECONDS]);
+ tm->tm_min = from_bcd(s, s->cmos_data[RTC_MINUTES]);
+ tm->tm_hour = from_bcd(s, s->cmos_data[RTC_HOURS]);
+ tm->tm_wday = from_bcd(s, s->cmos_data[RTC_DAY_OF_WEEK]);
+ tm->tm_mday = from_bcd(s, s->cmos_data[RTC_DAY_OF_MONTH]);
+ tm->tm_mon = from_bcd(s, s->cmos_data[RTC_MONTH]) - 1;
+ tm->tm_year = from_bcd(s, s->cmos_data[RTC_YEAR]) + 100;
+
+ /* update internal state */
+ s->buf_data[RTC_SECONDS] = s->cmos_data[RTC_SECONDS];
+ s->buf_data[RTC_MINUTES] = s->cmos_data[RTC_MINUTES];
+ s->buf_data[RTC_HOURS] = s->cmos_data[RTC_HOURS];
+ s->buf_data[RTC_DAY_OF_WEEK] = s->cmos_data[RTC_DAY_OF_WEEK];
+ s->buf_data[RTC_DAY_OF_MONTH] = s->cmos_data[RTC_DAY_OF_MONTH];
+ s->buf_data[RTC_MONTH] = s->cmos_data[RTC_MONTH];
+ s->buf_data[RTC_YEAR] = s->cmos_data[RTC_YEAR];
+ s->current_time = mktime(tm);
+}
+
+static void rtc_update_second(void *opaque)
+{
+ RTCState *s = opaque;
+
+ /* if the oscillator is not in normal operation, we do not update */
+ if ((s->cmos_data[RTC_REG_A] & 0x70) != 0x20) {
+ s->next_second_time += ticks_per_sec;
+ qemu_mod_timer(s->second_timer, s->next_second_time);
+ } else {
+ s->current_time++;
+
+ if (!(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
+ /* update in progress bit */
+ s->cmos_data[RTC_REG_A] |= REG_A_UIP;
+ }
+ qemu_mod_timer(s->second_timer2,
+ s->next_second_time + (ticks_per_sec * 99) / 100);
+ }
+}
+
+static void rtc_update_second2(void *opaque)
+{
+ RTCState *s = opaque;
time_t ti;
- ti = time(NULL);
- tm = gmtime(&ti);
- s->cmos_data[RTC_SECONDS] = to_bcd(tm->tm_sec);
- s->cmos_data[RTC_MINUTES] = to_bcd(tm->tm_min);
- s->cmos_data[RTC_HOURS] = to_bcd(tm->tm_hour);
- s->cmos_data[RTC_DAY_OF_WEEK] = to_bcd(tm->tm_wday);
- s->cmos_data[RTC_DAY_OF_MONTH] = to_bcd(tm->tm_mday);
- s->cmos_data[RTC_MONTH] = to_bcd(tm->tm_mon + 1);
- s->cmos_data[RTC_YEAR] = to_bcd(tm->tm_year % 100);
- s->cmos_data[REG_IBM_CENTURY_BYTE] = to_bcd((tm->tm_year / 100) + 19);
- s->cmos_data[REG_IBM_PS2_CENTURY_BYTE] = s->cmos_data[REG_IBM_CENTURY_BYTE];
+ ti = s->current_time;
+ rtc_set_date_buf(s, gmtime(&ti));
+
+ if (!(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
+ rtc_copy_date(s);
+ }
+
+ /* check alarm */
+ if (s->cmos_data[RTC_REG_B] & REG_B_AIE) {
+ if (((s->cmos_data[RTC_SECONDS_ALARM] & 0xc0) == 0xc0 ||
+ s->cmos_data[RTC_SECONDS_ALARM] == s->buf_data[RTC_SECONDS]) &&
+ ((s->cmos_data[RTC_MINUTES_ALARM] & 0xc0) == 0xc0 ||
+ s->cmos_data[RTC_MINUTES_ALARM] == s->buf_data[RTC_MINUTES]) &&
+ ((s->cmos_data[RTC_HOURS_ALARM] & 0xc0) == 0xc0 ||
+ s->cmos_data[RTC_HOURS_ALARM] == s->buf_data[RTC_HOURS])) {
+
+ s->cmos_data[RTC_REG_C] |= 0xa0;
+ pic_set_irq(s->irq, 1);
+ }
+ }
+
+ /* update ended interrupt */
+ if (s->cmos_data[RTC_REG_B] & REG_B_UIE) {
+ s->cmos_data[RTC_REG_C] |= 0x90;
+ pic_set_irq(s->irq, 1);
+ }
+
+ /* clear update in progress bit */
+ s->cmos_data[RTC_REG_A] &= ~REG_A_UIP;
+
+ s->next_second_time += ticks_per_sec;
+ qemu_mod_timer(s->second_timer, s->next_second_time);
}
static uint32_t cmos_ioport_read(void *opaque, uint32_t addr)
@@ -149,16 +297,10 @@ static uint32_t cmos_ioport_read(void *opaque, uint32_t addr)
case RTC_DAY_OF_MONTH:
case RTC_MONTH:
case RTC_YEAR:
- case REG_IBM_CENTURY_BYTE:
- case REG_IBM_PS2_CENTURY_BYTE:
- cmos_update_time(s);
ret = s->cmos_data[s->cmos_index];
break;
case RTC_REG_A:
ret = s->cmos_data[s->cmos_index];
- /* toggle update-in-progress bit for Linux (same hack as
- plex86) */
- s->cmos_data[RTC_REG_A] ^= 0x80;
break;
case RTC_REG_C:
ret = s->cmos_data[s->cmos_index];
@@ -177,19 +319,94 @@ static uint32_t cmos_ioport_read(void *opaque, uint32_t addr)
}
}
-void rtc_timer(void)
+static void rtc_set_date_buf(RTCState *s, const struct tm *tm)
{
- RTCState *s = &rtc_state;
- if (s->cmos_data[RTC_REG_B] & 0x50) {
- pic_set_irq(s->irq, 1);
+ s->buf_data[RTC_SECONDS] = to_bcd(s, tm->tm_sec);
+ s->buf_data[RTC_MINUTES] = to_bcd(s, tm->tm_min);
+ if (s->cmos_data[RTC_REG_B] & 0x02) {
+ /* 24 hour format */
+ s->buf_data[RTC_HOURS] = to_bcd(s, tm->tm_hour);
+ } else {
+ /* 12 hour format */
+ s->buf_data[RTC_HOURS] = to_bcd(s, tm->tm_hour % 12);
+ if (tm->tm_hour >= 12)
+ s->buf_data[RTC_HOURS] |= 0x80;
}
+ s->buf_data[RTC_DAY_OF_WEEK] = to_bcd(s, tm->tm_wday);
+ s->buf_data[RTC_DAY_OF_MONTH] = to_bcd(s, tm->tm_mday);
+ s->buf_data[RTC_MONTH] = to_bcd(s, tm->tm_mon + 1);
+ s->buf_data[RTC_YEAR] = to_bcd(s, tm->tm_year % 100);
+}
+
+static void rtc_copy_date(RTCState *s)
+{
+ s->cmos_data[RTC_SECONDS] = s->buf_data[RTC_SECONDS];
+ s->cmos_data[RTC_MINUTES] = s->buf_data[RTC_MINUTES];
+ s->cmos_data[RTC_HOURS] = s->buf_data[RTC_HOURS];
+ s->cmos_data[RTC_DAY_OF_WEEK] = s->buf_data[RTC_DAY_OF_WEEK];
+ s->cmos_data[RTC_DAY_OF_MONTH] = s->buf_data[RTC_DAY_OF_MONTH];
+ s->cmos_data[RTC_MONTH] = s->buf_data[RTC_MONTH];
+ s->cmos_data[RTC_YEAR] = s->buf_data[RTC_YEAR];
+}
+
+void rtc_set_memory(RTCState *s, int addr, int val)
+{
+ if (addr >= 0 && addr <= 127)
+ s->cmos_data[addr] = val;
+}
+
+void rtc_set_date(RTCState *s, const struct tm *tm)
+{
+ s->current_time = mktime((struct tm *)tm);
+ rtc_set_date_buf(s, tm);
+ rtc_copy_date(s);
+}
+
+static void rtc_save(QEMUFile *f, void *opaque)
+{
+ RTCState *s = opaque;
+
+ qemu_put_buffer(f, s->cmos_data, 128);
+ qemu_put_8s(f, &s->cmos_index);
+ qemu_put_be32s(f, &s->current_time);
+ qemu_put_buffer(f, s->buf_data, 10);
+
+ qemu_put_timer(f, s->periodic_timer);
+ qemu_put_be64s(f, &s->next_periodic_time);
+
+ qemu_put_be64s(f, &s->next_second_time);
+ qemu_put_timer(f, s->second_timer);
+ qemu_put_timer(f, s->second_timer2);
}
-void rtc_init(int base, int irq)
+static int rtc_load(QEMUFile *f, void *opaque, int version_id)
{
- RTCState *s = &rtc_state;
+ RTCState *s = opaque;
+
+ if (version_id != 1)
+ return -EINVAL;
- cmos_update_time(s);
+ qemu_get_buffer(f, s->cmos_data, 128);
+ qemu_get_8s(f, &s->cmos_index);
+ qemu_get_be32s(f, &s->current_time);
+ qemu_get_buffer(f, s->buf_data, 10);
+
+ qemu_get_timer(f, s->periodic_timer);
+ qemu_get_be64s(f, &s->next_periodic_time);
+
+ qemu_get_be64s(f, &s->next_second_time);
+ qemu_get_timer(f, s->second_timer);
+ qemu_get_timer(f, s->second_timer2);
+ return 0;
+}
+
+RTCState *rtc_init(int base, int irq)
+{
+ RTCState *s;
+
+ s = qemu_mallocz(sizeof(RTCState));
+ if (!s)
+ return NULL;
s->irq = irq;
s->cmos_data[RTC_REG_A] = 0x26;
@@ -197,7 +414,20 @@ void rtc_init(int base, int irq)
s->cmos_data[RTC_REG_C] = 0x00;
s->cmos_data[RTC_REG_D] = 0x80;
+ s->periodic_timer = qemu_new_timer(vm_clock,
+ rtc_periodic_timer, s);
+ s->second_timer = qemu_new_timer(vm_clock,
+ rtc_update_second, s);
+ s->second_timer2 = qemu_new_timer(vm_clock,
+ rtc_update_second2, s);
+
+ s->next_second_time = qemu_get_clock(vm_clock) + (ticks_per_sec * 99) / 100;
+ qemu_mod_timer(s->second_timer2, s->next_second_time);
+
register_ioport_write(base, 2, 1, cmos_ioport_write, s);
register_ioport_read(base, 2, 1, cmos_ioport_read, s);
+
+ register_savevm("mc146818rtc", base, 1, rtc_save, rtc_load, s);
+ return s;
}