CPU and GPU Reg Funcs Decomp (#16)

* decomp/doc cpu funcs and gpu reg funcs

* use Cpu32 macro funcs

* address review comments

* decomp SetBGOBJEnableFlags

1 files changed, 154 insertions, 11 deletions

diff --git a/src/main.c b/src/main.c
index 687ef6d..2d586a5 100644
--- a/src/main.c
+++ b/src/main.c
@@ -5,8 +5,16 @@
 
 extern char ewram_start[];
 
+extern u8 gUnknown_202D4B8;
+extern void *gUnknown_202D5F0[6];
 extern u16 gUnknown_202D7FC;
 extern u8 gUnknown_202D7FE;
+extern u8 gInterruptsEnabled;
+extern u16 gUnknown_203B0AC;
+extern s16 gUnknown_203B0AE;
+extern u32 gIntrTable[];
+extern u32 IntrMain;
+
 
 extern char alt_203B038[];
 
@@ -21,6 +29,7 @@ extern char unk_code_ram[];
 extern char unk_code_ram_end[];
 
 extern u8 gUnknown_80B9BF1[];
+extern u32 gUnknown_80B9C00;
 
 extern char gUnknown_8270000[];
 
@@ -37,11 +46,20 @@ extern void sub_80057E8(void);
 extern void InitFileSystem(void);
 extern void sub_80098A0(void);
 extern void InitGraphics(void);
-extern void sub_800B6F4(int, void *);
 extern void GameLoop(void);
 extern void Hang(void);
 extern void sub_800CE54(void);
 
+extern void nullsub_17(void);
+extern void sub_800BD08(void); // music initializer
+extern void sub_800D6AC(void);
+extern void sub_800D7D0(void);
+
+bool8 EnableInterrupts(void);
+void InitIntrTable(const u32 *interrupt_table);
+void *sub_800B6F4(u32 index, void * new_callback);
+
+
 void AgbMain(void)
 {
     u8 value[4];
@@ -76,16 +94,16 @@ void AgbMain(void)
     REG_WIN1H = 0;
     REG_WIN0V = 0;
     REG_WIN1V = 0;
-    REG_WININ = 16191;
-    REG_WINOUT = 61;
-    gUnknown_202D7FC = REG_BLDCNT = 15426;
-    REG_BLDALPHA = 1546;
+    REG_WININ = WININ_WIN0_ALL | WININ_WIN1_ALL; // 16191
+    REG_WINOUT = WINOUT_WIN01_BG0 | WINOUT_WIN01_BG2 | WINOUT_WIN01_BG3 | WINOUT_WIN01_OBJ | WINOUT_WIN01_CLR; // 61
+    gUnknown_202D7FC = REG_BLDCNT = BLDCNT_TGT1_BG1 | BLDCNT_EFFECT_BLEND | BLDCNT_TGT2_BG2 | BLDCNT_TGT2_BG3 | BLDCNT_TGT2_BD | BLDCNT_TGT2_OBJ; // 15426
+    REG_BLDALPHA = BLDALPHA_BLEND(10, 6); // 1546
     gUnknown_202D7FE = 0;
-    REG_BG0CNT = 11264;
-    REG_BG1CNT = 11521;
-    REG_BG2CNT = 11786;
-    REG_BG3CNT = 12043;
-    REG_DISPCNT = 32704;
+    REG_BG0CNT = BGCNT_PRIORITY(0) | BGCNT_CHARBASE(0) | BGCNT_WRAP | BGCNT_SCREENBASE(12); // 11264
+    REG_BG1CNT = BGCNT_PRIORITY(1) | BGCNT_CHARBASE(0) | BGCNT_WRAP | BGCNT_SCREENBASE(13); // 11521
+    REG_BG2CNT = BGCNT_PRIORITY(2) | BGCNT_CHARBASE(2) | BGCNT_WRAP | BGCNT_SCREENBASE(14); // 11786
+    REG_BG3CNT = BGCNT_PRIORITY(3) | BGCNT_CHARBASE(2) | BGCNT_WRAP | BGCNT_SCREENBASE(15); // 12043
+    REG_DISPCNT = DISPCNT_WIN1_ON | DISPCNT_WIN0_ON | DISPCNT_OBJ_ON | DISPCNT_BG_ALL_ON | DISPCNT_OBJ_1D_MAP | DISPCNT_FORCED_BLANK; // 32704
     sub_800CDA8(1);
     sub_800B540();
     InitFlash();
@@ -102,7 +120,132 @@ void AgbMain(void)
     sub_80098A0();
     InitGraphics();
     sub_800B6F4(1, sub_800CE54);
-    REG_DISPCNT = 32576;
+    REG_DISPCNT = DISPCNT_WIN1_ON | DISPCNT_WIN0_ON | DISPCNT_OBJ_ON | DISPCNT_BG_ALL_ON | DISPCNT_OBJ_1D_MAP; // 32576
     GameLoop();
     Hang();
 }
+
+void sub_800B540(void)
+{
+    s32 i;
+    for (i = 0; i < 6; i++) {
+        gUnknown_202D5F0[i] = NULL;
+    }
+
+    nullsub_17();
+    sub_800BD08(); // initialize music and stop DMAs
+
+    while(REG_VCOUNT <= 159){}
+
+    REG_IE ^= INTR_FLAG_TIMER3 | INTR_FLAG_VBLANK | INTR_FLAG_VCOUNT; // 0x45
+
+    *(u8*)&REG_DISPCNT |= DISPCNT_FORCED_BLANK; 
+
+    InitIntrTable(&gUnknown_80B9C00); // set up intrrupt vector/table
+
+    REG_TM3CNT = (TIMER_64CLK | TIMER_INTR_ENABLE | TIMER_ENABLE) << 16; 
+
+    REG_IE |= INTR_FLAG_GAMEPAK | INTR_FLAG_TIMER3 | INTR_FLAG_VCOUNT | INTR_FLAG_VBLANK; // 0x2045
+    REG_DISPSTAT = DISPSTAT_VCOUNT_INTR | DISPSTAT_VBLANK_INTR;
+    gUnknown_203B0AE = -1;
+    gUnknown_203B0AC = 0;
+    sub_800D6AC(); // Some other IO REG update func
+    sub_800D7D0(); // Some other IO REG update func
+    gInterruptsEnabled = 1;
+    EnableInterrupts();
+
+    while(REG_VCOUNT <= 159){}
+}
+
+bool8 EnableInterrupts(void)
+{
+    if(!gInterruptsEnabled)
+    {
+        return FALSE;
+    }
+
+    if(REG_IME & 1)
+    {
+        return FALSE;
+    }
+    else
+    {
+        REG_IME = 1;
+        return TRUE;
+    }
+}
+
+bool8 DisableInterrupts(void)
+{
+    if(!gInterruptsEnabled)
+    {
+        return FALSE;
+    }
+
+    if(!(REG_IME & 1))
+    {
+        return FALSE;
+    }
+    else
+    {
+        REG_IME = 0;
+        return TRUE;
+    }
+
+}
+
+bool8 sub_800B650(void)
+{
+    if(!gInterruptsEnabled)
+    {
+        return FALSE;
+    }
+
+    if(REG_IME & 1)
+    {
+        return FALSE;
+    }
+    else
+    {
+        return TRUE;
+    }
+}
+
+void SetInterruptFlag(u16 flag)
+{
+    if(!gInterruptsEnabled)
+    {
+        return;
+    }
+
+    REG_IME = 0;
+    INTR_CHECK |= flag;
+    REG_IME = 1;
+}
+
+void InitIntrTable(const u32 *interrupt_table)
+{
+    CpuCopy32(interrupt_table, &gIntrTable, 0x18); // 0x18 = 0x6 * 4 (0x4f00 is 32 bits)
+    CpuCopy32(&IntrMain, &gUnknown_202D4B8, 0x120); // 0x120 = 0x48 * 4 (0x4f00 is 32 bits)
+    INTR_VECTOR = &gUnknown_202D4B8;
+}
+
+u32 *sub_800B6E8(u32 r0)
+{
+    return &gIntrTable[r0];
+}
+
+void *sub_800B6F4(u32 index, void * new_callback)
+{
+    void *old_callback;
+    u32 interrupt_var;
+
+    interrupt_var = DisableInterrupts();
+    old_callback = gUnknown_202D5F0[index];
+    gUnknown_202D5F0[index] = new_callback;
+    if(interrupt_var){
+        EnableInterrupts();
+    }
+    return old_callback;
+}
+