diff options
| -rw-r--r-- | hw/mc146818rtc.c | 9 | ||||
| -rw-r--r-- | hw/mc146818rtc_regs.h | 1 |
2 files changed, 10 insertions, 0 deletions
diff --git a/hw/mc146818rtc.c b/hw/mc146818rtc.c index 175ddac6fb..b41eb4b944 100644 --- a/hw/mc146818rtc.c +++ b/hw/mc146818rtc.c @@ -221,6 +221,15 @@ static void cmos_ioport_write(void *opaque, uint32_t addr, uint32_t data) 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)); break; diff --git a/hw/mc146818rtc_regs.h b/hw/mc146818rtc_regs.h index 3ab37709f0..fc10076ece 100644 --- a/hw/mc146818rtc_regs.h +++ b/hw/mc146818rtc_regs.h @@ -58,5 +58,6 @@ #define REG_C_IRQF 0x80 #define REG_C_PF 0x40 #define REG_C_AF 0x20 +#define REG_C_MASK 0x70 #endif |