On mouse events, do not signal mouse IRQ unless: a) Guest enabled AUX mouse reporting b) INT 15h called to enable reporting c) INT 33h has visible cursor, interrupt handler, or guest is polling mouse info. Do not process mouse movement into mouse device input while debugger is active. This should fix the issue where IRQ12 is consistently seen active in the debugger, whether it is stuck or has the appearance of being stuck on.

Author: joncampbell123

src/hardware/keyboard.cpp

@@ -253,6 +253,11 @@ int KEYBOARD_AUX_Active() {
     return keyb.auxactive && !keyb.ps2mouse.int33_taken;
 }
 
+int KEYBOARD_PS2REPORT_Active() {
+	/* HACK: INT 15h really needs to issue Enable AUX, but for now, report if PS/2 mouse reporting active */
+	return keyb.ps2mouse.reporting;
+}
+
 static void KEYBOARD_SetPort60(uint16_t val) {
     keyb.auxchanged=(val&AUX)>0;
     keyb.p60changed=true;

src/ints/mouse.cpp

@@ -251,6 +251,7 @@ static struct {
     bool first_range_setx;
     bool first_range_sety;
     bool in_UIR;
+    bool polled;
     uint8_t mode;
     int16_t gran_x,gran_y;
     int scrollwheel;
@@ -428,6 +429,23 @@ void ChangeMouseReportRate(unsigned int new_rate) {
 	}
 }
 
+int KEYBOARD_PS2REPORT_Active();
+
+bool MouseInterruptEnabled(void) {
+	if (!IS_PC98_ARCH && KEYBOARD_AUX_Active())
+		return true;
+	if (KEYBOARD_PS2REPORT_Active()) // FIXME: INT 15h needs to issue keyboard command "enable AUX"
+		return true;
+	if (mouse.polled)
+		return true;
+	if (mouse.sub_mask)
+		return true;
+	if (!mouse.hidden)
+		return true;
+
+	return false;
+}
+
 void MOUSE_Limit_Events(Bitu /*val*/) {
     mouse.timer_in_progress = false;
 
@@ -442,7 +460,7 @@ void MOUSE_Limit_Events(Bitu /*val*/) {
         PIC_AddEvent(MOUSE_Limit_Events,MOUSE_DELAY);
 
         if (MOUSE_IRQ != 0) {
-            if (!IS_PC98_ARCH)
+            if (!IS_PC98_ARCH && MouseInterruptEnabled())
                 PIC_ActivateIRQ(MOUSE_IRQ);
         }
     }
@@ -468,7 +486,7 @@ INLINE void Mouse_AddEvent(uint8_t type) {
         PIC_AddEvent(MOUSE_Limit_Events,MOUSE_DELAY);
 
         if (MOUSE_IRQ != 0) {
-            if (!IS_PC98_ARCH)
+            if (!IS_PC98_ARCH && MouseInterruptEnabled())
                 PIC_ActivateIRQ(MOUSE_IRQ);
         }
     }
@@ -1567,6 +1585,7 @@ static Bitu INT33_Handler(void) {
     switch (reg_ax) {
     case 0x00:  /* MS MOUSE - RESET DRIVER AND READ STATUS */
         Mouse_ResetHardware();
+        mouse.polled = false;
         goto software_reset;
     case 0x01:  /* MS MOUSE v1.0+ - SHOW MOUSE CURSOR */
         if (mouse.hidden) mouse.hidden--;
@@ -1594,6 +1613,7 @@ static Bitu INT33_Handler(void) {
         }
         reg_cx=POS_X;
         reg_dx=POS_Y;
+        mouse.polled = true;
         mouse.first_range_setx = false;
         mouse.first_range_sety = false;
         if (en_int33_hide_if_polling) int33_last_poll = PIC_FullIndex();
@@ -1639,6 +1659,7 @@ static Bitu INT33_Handler(void) {
 			}
             if (en_int33_hide_if_polling) int33_last_poll = PIC_FullIndex();
         }
+        mouse.polled = true;
         Mouse_Used();
         break;
     case 0x06:  /* MS MOUSE v1.0+ - RETURN BUTTON RELEASE DATA */
@@ -1668,6 +1689,7 @@ static Bitu INT33_Handler(void) {
 			}
             if (en_int33_hide_if_polling) int33_last_poll = PIC_FullIndex();
         }
+        mouse.polled = true;
         Mouse_Used();
         break;
     case 0x07:  /* MS MOUSE v1.0+ - DEFINE HORIZONTAL CURSOR RANGE */
@@ -1839,6 +1861,7 @@ static Bitu INT33_Handler(void) {
         DrawCursor();
         break;
     case 0x0b:  /* MS MOUSE v1.0+ - READ MOTION COUNTERS */
+        mouse.polled = true;
         Mouse_Read_Motion_Data();
         break;
     case 0x0c:  /* MS MOUSE v1.0+ - DEFINE INTERRUPT SUBROUTINE PARAMETERS */
@@ -2042,6 +2065,7 @@ static Bitu INT33_Handler(void) {
         reg_dx = (uint16_t)mouse.max_y;
         break;
     case 0x27:  /* MS MOUSE v7.01+ - GET SCREEN/CURSOR MASKS AND MICKEY COUNTS */
+        mouse.polled = true;
         reg_ax = mouse.textAndMask;
         reg_bx = mouse.textXorMask;
         Mouse_Read_Motion_Data();
@@ -2465,6 +2489,7 @@ void MOUSE_Startup(Section *sec) {
     mouse.timer_in_progress = false;
     mouse.mode = 0xFF; //Non existing mode
     mouse.scrollwheel = 0;
+    mouse.polled = 0;
 
     mouse.sub_mask=0;
     mouse.sub_seg=0x6362;   // magic value