Revert "Rework disabling of ps2 port irqs."

This reverts commit 6f702dd6987b22e9bce472fe61910392af17416a.

That patch introduced a regression by enabling mouse interrupts by
default.  It also appears that disabling interrupts by software alone
will not work well with some old DOS programs that hook the keyboard
irq.

4 files changed, 68 insertions, 65 deletions

diff --git a/src/biosvar.h b/src/biosvar.h
index 808793d2..ea2d67d9 100644
--- a/src/biosvar.h
+++ b/src/biosvar.h
@@ -97,7 +97,7 @@ struct bios_data_area_s {
     u8 floppy_media_state[4];
     u8 floppy_track[2];
     u8 kbd_flag2;
-    u8 kbd_flag3;
+    u8 kbd_led;
     struct segoff_s user_wait_complete_flag;
     u32 user_wait_timeout;
     // 40:A0
@@ -123,33 +123,6 @@ struct bios_data_area_s {
 #define FMS_DOUBLE_STEPPING         (1<<5)
 #define FMS_DATA_RATE_MASK          (0xc0)
 
-// Bit definitions for kbd_flag[0123]
-#define KF0_RSHIFT       (1<<0)
-#define KF0_LSHIFT       (1<<1)
-#define KF0_CTRLACTIVE   (1<<2)
-#define KF0_ALTACTIVE    (1<<3)
-#define KF0_SCROLLACTIVE (1<<4)
-#define KF0_NUMACTIVE    (1<<5)
-#define KF0_CAPSACTIVE   (1<<6)
-
-#define KF1_LCTRL        (1<<0)
-#define KF1_LALT         (1<<1)
-#define KF1_PAUSEACTIVE  (1<<3)
-#define KF1_SCROLL       (1<<4)
-#define KF1_NUM          (1<<5)
-#define KF1_CAPS         (1<<6)
-
-#define KF2_LAST_E1    (1<<0)
-#define KF2_LAST_E0    (1<<1)
-#define KF2_RCTRL      (1<<2)
-#define KF2_RALT       (1<<3)
-#define KF2_101KBD     (1<<4)
-
-#define KF3_SCROLL_LED  (1<<0)
-#define KF3_NUM_LED     (1<<1)
-#define KF3_CAPS_LED    (1<<2)
-#define KF3_CMD_PENDING (1<<6)
-
 // Accessor functions
 #define GET_BDA(var) \
     GET_FARVAR(SEG_BDA, ((struct bios_data_area_s *)0)->var)
@@ -243,6 +216,7 @@ struct extended_bios_data_area_s {
     u8 other2[0xC4];
 
     // 0x121 - Begin custom storage.
+    u8 ps2ctr;
     struct usbkeyinfo usbkey_last;
 
     int RTCusers;
diff --git a/src/kbd.c b/src/kbd.c
index 44dce573..6f3ae15d 100644
--- a/src/kbd.c
+++ b/src/kbd.c
@@ -11,6 +11,28 @@
 #include "bregs.h" // struct bregs
 #include "ps2port.h" // kbd_command
 
+// Bit definitions for BDA kbd_flag[012]
+#define KF0_RSHIFT       (1<<0)
+#define KF0_LSHIFT       (1<<1)
+#define KF0_CTRLACTIVE   (1<<2)
+#define KF0_ALTACTIVE    (1<<3)
+#define KF0_SCROLLACTIVE (1<<4)
+#define KF0_NUMACTIVE    (1<<5)
+#define KF0_CAPSACTIVE   (1<<6)
+
+#define KF1_LCTRL        (1<<0)
+#define KF1_LALT         (1<<1)
+#define KF1_PAUSEACTIVE  (1<<3)
+#define KF1_SCROLL       (1<<4)
+#define KF1_NUM          (1<<5)
+#define KF1_CAPS         (1<<6)
+
+#define KF2_LAST_E1    (1<<0)
+#define KF2_LAST_E0    (1<<1)
+#define KF2_RCTRL      (1<<2)
+#define KF2_RALT       (1<<3)
+#define KF2_101KBD     (1<<4)
+
 void
 kbd_setup(void)
 {
@@ -201,7 +223,7 @@ static void
 set_leds(void)
 {
     u8 shift_flags = (GET_BDA(kbd_flag0) >> 4) & 0x07;
-    u8 kbd_led = GET_BDA(kbd_flag3);
+    u8 kbd_led = GET_BDA(kbd_led);
     u8 led_flags = kbd_led & 0x07;
     if (shift_flags == led_flags)
         return;
@@ -211,7 +233,7 @@ set_leds(void)
         // Error
         return;
     kbd_led = (kbd_led & ~0x07) | shift_flags;
-    SET_BDA(kbd_flag3, kbd_led);
+    SET_BDA(kbd_led, kbd_led);
 }
 
 // INT 16h Keyboard Service Entry Point
diff --git a/src/mouse.c b/src/mouse.c
index 3004d786..8389d2a0 100644
--- a/src/mouse.c
+++ b/src/mouse.c
@@ -29,8 +29,13 @@ mouse_setup(void)
 #define RET_ENOHANDLER   0x05
 
 static int
-disable_mouse(void)
+disable_mouse(u16 ebda_seg)
 {
+    u8 ps2ctr = GET_EBDA2(ebda_seg, ps2ctr);
+    ps2ctr |= I8042_CTR_AUXDIS;
+    ps2ctr &= ~I8042_CTR_AUXINT;
+    SET_EBDA2(ebda_seg, ps2ctr, ps2ctr);
+
     return aux_command(PSMOUSE_CMD_DISABLE, NULL);
 }
 
@@ -38,7 +43,8 @@ disable_mouse(void)
 static void
 mouse_15c20000(struct bregs *regs)
 {
-    int ret = disable_mouse();
+    u16 ebda_seg = get_ebda_seg();
+    int ret = disable_mouse(ebda_seg);
     if (ret)
         set_code_invalid(regs, RET_ENEEDRESEND);
     else
@@ -49,12 +55,18 @@ mouse_15c20000(struct bregs *regs)
 static void
 mouse_15c20001(struct bregs *regs)
 {
-    u8 mouse_flags_2 = GET_EBDA(mouse_flag2);
+    u16 ebda_seg = get_ebda_seg();
+    u8 mouse_flags_2 = GET_EBDA2(ebda_seg, mouse_flag2);
     if ((mouse_flags_2 & 0x80) == 0) {
         set_code_invalid(regs, RET_ENOHANDLER);
         return;
     }
 
+    u8 ps2ctr = GET_EBDA2(ebda_seg, ps2ctr);
+    ps2ctr &= ~I8042_CTR_AUXDIS;
+    ps2ctr |= I8042_CTR_AUXINT;
+    SET_EBDA2(ebda_seg, ps2ctr, ps2ctr);
+
     int ret = aux_command(PSMOUSE_CMD_ENABLE, NULL);
     if (ret)
         set_code_invalid(regs, RET_ENEEDRESEND);
@@ -229,7 +241,7 @@ mouse_15c207(struct bregs *regs)
         /* remove handler */
         if ((mouse_flags_2 & 0x80) != 0) {
             mouse_flags_2 &= ~0x80;
-            disable_mouse();
+            disable_mouse(ebda_seg);
         }
     } else {
         /* install handler */
diff --git a/src/ps2port.c b/src/ps2port.c
index 26c55f28..54227457 100644
--- a/src/ps2port.c
+++ b/src/ps2port.c
@@ -151,18 +151,6 @@ process_ps2byte(u8 status, u8 data)
         process_key(data);
 }
 
-static void
-process_ps2bytes(void)
-{
-    for (;;) {
-        u8 status = inb(PORT_PS2_STATUS);
-        if (!(status & I8042_STR_OBF))
-            return;
-        u8 data = inb(PORT_PS2_DATA);
-        process_ps2byte(status, data);
-    }
-}
-
 static int
 ps2_recvbyte(int aux, int needack, int timeout)
 {
@@ -223,13 +211,22 @@ ps2_sendbyte(int aux, u8 command, int timeout)
 static int
 ps2_command(int aux, int command, u8 *param)
 {
-    int ret;
+    int ret2;
     int receive = (command >> 8) & 0xf;
     int send = (command >> 12) & 0xf;
 
-    // Disable processing of interrupts.
-    u8 kbdflag = GET_BDA(kbd_flag3);
-    SET_BDA(kbd_flag3, kbdflag | KF3_CMD_PENDING);
+    // Disable interrupts and keyboard/mouse.
+    u8 ps2ctr = GET_EBDA(ps2ctr);
+    u8 newctr = ps2ctr;
+    if (aux)
+        newctr |= I8042_CTR_KBDDIS;
+    else
+        newctr |= I8042_CTR_AUXDIS;
+    newctr &= ~(I8042_CTR_KBDINT|I8042_CTR_AUXINT);
+    dprintf(6, "i8042 ctr old=%x new=%x\n", ps2ctr, newctr);
+    int ret = i8042_command(I8042_CMD_CTL_WCTR, &newctr);
+    if (ret)
+        return ret;
 
     if (command == ATKBD_CMD_RESET_BAT) {
         // Reset is special wrt timeouts.
@@ -275,10 +272,10 @@ ps2_command(int aux, int command, u8 *param)
     ret = 0;
 
 fail:
-    // Restore processing of interrupts.
-    if (!(kbdflag & KF3_CMD_PENDING))
-        process_ps2bytes();
-    SET_BDA(kbd_flag3, kbdflag);
+    // Restore interrupts and keyboard/mouse.
+    ret2 = i8042_command(I8042_CMD_CTL_WCTR, &ps2ctr);
+    if (ret2)
+        return ret2;
 
     return ret;
 }
@@ -311,10 +308,14 @@ aux_command(int command, u8 *param)
 static void
 process_ps2irq(void)
 {
-    if (GET_BDA(kbd_flag3) & KF3_CMD_PENDING)
-        // PS/2 command in progress - it will handle this event.
+    u8 status = inb(PORT_PS2_STATUS);
+    if (!(status & I8042_STR_OBF)) {
+        dprintf(1, "ps2 irq but no data.\n");
         return;
-    process_ps2bytes();
+    }
+    u8 data = inb(PORT_PS2_DATA);
+
+    process_ps2byte(status, data);
 }
 
 // INT74h : PS/2 mouse hardware interrupt
@@ -403,12 +404,8 @@ keyboard_init(void *data)
     if (ret)
         return;
 
-    // Mode: scan code convert, enable IRQ 1, enable IRQ 12
-    param[0] = I8042_CTR_XLATE | I8042_CTR_KBDINT | I8042_CTR_AUXINT;
-    ret = i8042_command(I8042_CMD_CTL_WCTR, param);
-    if (ret)
-        return;
-    CLEARBITS_BDA(kbd_flag3, KF3_CMD_PENDING);
+    // Keyboard Mode: scan code convert, disable mouse, enable IRQ 1
+    SET_EBDA(ps2ctr, I8042_CTR_AUXDIS | I8042_CTR_XLATE | I8042_CTR_KBDINT);
 
     /* Enable keyboard */
     ret = kbd_command(ATKBD_CMD_ENABLE, NULL);
@@ -426,8 +423,6 @@ ps2port_setup(void)
         return;
     dprintf(3, "init ps2port\n");
 
-    // Setup irqs, but disable them until init complete.
-    SETBITS_BDA(kbd_flag3, KF3_CMD_PENDING);
     enable_hwirq(1, entry_09);
     enable_hwirq(12, entry_74);