split toggling masks and interrupts themselves

inc/n64_cp0.inc

@@ -43,7 +43,7 @@ constant CP0_STATUS_IM4($1000) // Interrupt Mask 4 (External)
 constant CP0_STATUS_IM5($2000) // Interrupt Mask 5 (External)
 constant CP0_STATUS_IM6($4000) // Interrupt Mask 6 (External)
 constant CP0_STATUS_IM7($8000) // Interrupt Mask 7 (External)
-constant CP0_STATUS_IM_ALL($FF01) // enable all interrupts
+constant CP0_STATUS_IM_ALL($FF00) // all interrupt masks
 
 // note that these are all masks.
 constant CP0_CAUSE_CODE($007C) // actually supposed to be called ExcCode

inc/n64_sp.inc

@@ -77,7 +77,7 @@ macro SP_BUSY_WAIT() {
 -
     lw      t0, SP_STATUS(a0)
     andi    t0, 0x1C
-    sltu    t0, r0, t0 // TODO: rewrite this
+    sltu    t0, r0, t0
     bnez    t0,-
     nop
 }

inc/n64_util.inc

@@ -1,4 +1,20 @@
 macro EnableInt() {
+    // careful not to touch unrelated flags here
+    mfc0    t0, CP0_Status
+    addiu   at, r0, CP0_STATUS_IE
+    or      t0, at
+    mtc0    t0, CP0_Status
+}
+
+macro DisableInt() {
+    // careful not to touch unrelated flags here
+    mfc0    t0, CP0_Status
+    addiu   at, r0, ~CP0_STATUS_IE
+    and     t0, at
+    mtc0    t0, CP0_Status
+}
+
+macro SetIntMask() {
     lli     t0, MI_INTR_MASK_ALL_SET
     lui     a0, MI_BASE
     sw      t0, MI_INTR_MASK(a0)
@@ -9,7 +25,7 @@ macro EnableInt() {
     mtc0    t1, CP0_Status
 }
 
-macro DisableInt() {
+macro ClearIntMask() {
     lli     t0, MI_INTR_MASK_ALL_CLR
     lui     a0, MI_BASE
     sw      t0, MI_INTR_MASK(a0)

kernel.asm

@@ -40,7 +40,7 @@ Start:
 
     // enable CPU interrupts.
     mfc0    t1, CP0_Status
-    ori     t1, t1, CP0_STATUS_IM_ALL
+    ori     t1, t1, CP0_STATUS_IM_ALL | CP0_STATUS_IE
     mtc0    t1, CP0_Status
 
     // enable even more interrupts.
@@ -440,7 +440,7 @@ K_MI_SP:
     lui     a1, SP_BASE
     sw      t0, SP_STATUS(a1)
 
-    // then check andi t1, SG1 | SG2 ?
+    // then check andi t1, SP_SG1 | SP_SG2 ?
 
     lw      t0, K_HISTORY(k0)
     ori     t0, 0x01

main.asm

@@ -85,7 +85,7 @@ include "dlist.asm" // takes a0
     nop
 
 Start3D:
-    DisableInt()
+    ClearIntMask()
 
     // stuff i'm borrowing from zelda:
     lui     a0, SP_BASE
@@ -126,7 +126,7 @@ Start3D:
     sw      t0, SP_STATUS(a0)
     nop
 
-    EnableInt()
+    SetIntMask()
 
 MainLoop:
     lui     a0, K_BASE