#define KBD_OUT_OBF 0x10 /* Keyboard output buffer full */
#define KBD_OUT_MOUSE_OBF 0x20 /* Mouse output buffer full */
+/* OSes typically write 0xdd/0xdf to turn the A20 line off and on.
+ * We make the default value of the outport include these four bits,
+ * so that the subsection is rarely necessary.
+ */
+#define KBD_OUT_ONES 0xcc
+
/* Mouse Commands */
#define AUX_SET_SCALE11 0xE6 /* Set 1:1 scaling */
#define AUX_SET_SCALE21 0xE7 /* Set 2:1 scaling */
s->mode = KBD_MODE_KBD_INT | KBD_MODE_MOUSE_INT;
s->status = KBD_STAT_CMD | KBD_STAT_UNLOCKED;
- s->outport = KBD_OUT_RESET | KBD_OUT_A20;
+ s->outport = KBD_OUT_RESET | KBD_OUT_A20 | KBD_OUT_ONES;
s->outport_present = false;
}
static uint8_t kbd_outport_default(KBDState *s)
{
- return KBD_OUT_RESET | KBD_OUT_A20
+ return KBD_OUT_RESET | KBD_OUT_A20 | KBD_OUT_ONES
| (s->status & KBD_STAT_OBF ? KBD_OUT_OBF : 0)
| (s->status & KBD_STAT_MOUSE_OBF ? KBD_OUT_MOUSE_OBF : 0);
}