[Qemu-devel] [PATCHv2] Add rtc reset function.

[Gleb Natapov <gleb@redhat.com>]

On reset:
Periodic Interrupt Enable (PIE) bit is cleared to zero
Alarm Interrupt Enable (AIE) bit is cleared to zero
Update ended Interrupt Flag (UF) bit is cleared to zero
Interrupt Request status Flag (IRQF) bit is cleared to zero
Periodic Interrupt Flag (PF) bit is cleared to zero
Alarm Interrupt Flag (AF) bit is cleared to zero
Square Wave output Enable (SQWE) zero

Signed-off-by: Gleb Natapov <gleb@redhat.com>
diff --git a/hw/mc146818rtc.c b/hw/mc146818rtc.c
index 888b85a..8c446e1 100644
--- a/hw/mc146818rtc.c
+++ b/hw/mc146818rtc.c
@@ -57,6 +57,11 @@
 #define REG_B_SQWE 0x08
 #define REG_B_DM   0x04
 
+#define REG_C_UF   0x10
+#define REG_C_IRQF 0x80
+#define REG_C_PF   0x40
+#define REG_C_AF   0x20
+
 struct RTCState {
     uint8_t cmos_data[128];
     uint8_t cmos_index;
@@ -568,6 +573,21 @@ static int rtc_load_td(QEMUFile *f, void *opaque, int version_id)
 }
 #endif
 
+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);
+
+    qemu_irq_lower(s->irq);
+
+#ifdef TARGET_I386
+    if (rtc_td_hack)
+	    s->irq_coalesced = 0;
+#endif
+}
+
 RTCState *rtc_init_sqw(int base, qemu_irq irq, qemu_irq sqw_irq, int base_year)
 {
     RTCState *s;
@@ -606,6 +626,8 @@ RTCState *rtc_init_sqw(int base, qemu_irq irq, qemu_irq sqw_irq, int base_year)
     if (rtc_td_hack)
         register_savevm("mc146818rtc-td", base, 1, rtc_save_td, rtc_load_td, s);
 #endif
+    qemu_register_reset(rtc_reset, 0, s);
+
     return s;
 }
 
@@ -721,5 +743,6 @@ RTCState *rtc_mm_init(target_phys_addr_t base, int it_shift, qemu_irq irq,
     if (rtc_td_hack)
         register_savevm("mc146818rtc-td", base, 1, rtc_save_td, rtc_load_td, s);
 #endif
+    qemu_register_reset(rtc_reset, 0, s);
     return s;
 }
--
			Gleb.