new macros for declaring uninitialized IWRAM data

5 files changed, 53 insertions, 11 deletions

diff --git a/include/gba/gba.h b/include/gba/gba.h
index 9cacbfee0..06067dacf 100644
--- a/include/gba/gba.h
+++ b/include/gba/gba.h
@@ -32,12 +32,32 @@ typedef u32 bool32;
 
 #define ALIGNED(n) __attribute__((aligned(n)))
 
+// The original build process placed COMMON data (i.e. uninitialized globals)
+// in IWRAM after the static variables.
+// When ld places COMMON variables in the output, it aligns the variable
+// according to the size of the variable, with a maximum alignment of 16. This
+// results in large alignment values.
+// Initialized variables are aligned according to the size of the largest
+// primitive type in the object, so their alignment will often be smaller.
+// However, we cannot use COMMON data in pokeruby because the order of COMMON
+// data in the output is not reliable. Instead, we need to initialize the
+// variables so that their order in the source file is preserved in the output.
+// But using initialized variables brings us into conflict with those large
+// alignment values.
+// These macros allow us to get around this by manually specifying what the
+// alignment would be if the variable were uninitialized.
+#define COMM(decl, n) IWRAM_DATA ALIGNED(1 << n) decl = {0};
+#define COMM_0(decl) COMM(decl, 0)
+#define COMM_1(decl) COMM(decl, 1)
+#define COMM_2(decl) COMM(decl, 2)
+#define COMM_4(decl) COMM(decl, 4)
+
 #include "gba/io_reg.h"
 #include "gba/syscall.h"
 #include "gba/macro.h"
 
 #define SOUND_INFO_PTR (*(struct SoundInfo **)0x3007FF0)
 #define INTR_CHECK     (*(u16 *)0x3007FF8)
-#define INTR_VECTOR    (*(u32 *)0x3007FFC)
+#define INTR_VECTOR    (*(void **)0x3007FFC)
 
 #endif // GUARD_GBA_GBA_H
diff --git a/include/gba/io_reg.h b/include/gba/io_reg.h
index e29441f19..9673cd0ef 100644
--- a/include/gba/io_reg.h
+++ b/include/gba/io_reg.h
@@ -490,6 +490,7 @@
 #define DMA_START_VBLANK  0x1000
 #define DMA_START_HBLANK  0x2000
 #define DMA_START_SPECIAL 0x3000
+#define DMA_START_MASK    0x3000
 #define DMA_INTR_ENABLE   0x4000
 #define DMA_ENABLE        0x8000
 
diff --git a/include/gba/macro.h b/include/gba/macro.h
index 1a778ef84..a886d12d4 100644
--- a/include/gba/macro.h
+++ b/include/gba/macro.h
@@ -49,4 +49,12 @@
 #define DmaCopy16(dmaNum, src, dest, size) DMA_COPY(dmaNum, src, dest, size, 16)
 #define DmaCopy32(dmaNum, src, dest, size) DMA_COPY(dmaNum, src, dest, size, 32)
 
+#define DmaStop(dmaNum)                                         \
+{                                                               \
+    vu16 *dmaRegs = (vu16 *)REG_ADDR_DMA##dmaNum;               \
+    dmaRegs[5] &= ~(DMA_START_MASK | DMA_DREQ_ON | DMA_REPEAT); \
+    dmaRegs[5] &= ~DMA_ENABLE;                                  \
+    dmaRegs[5];                                                 \
+}
+
 #endif // GUARD_GBA_MACRO_H
diff --git a/include/gba/syscall.h b/include/gba/syscall.h
index 4d69907ee..9b2b81311 100644
--- a/include/gba/syscall.h
+++ b/include/gba/syscall.h
@@ -1,12 +1,26 @@
 #ifndef GUARD_GBA_SYSCALL_H
 #define GUARD_GBA_SYSCALL_H
 
+#define RESET_EWRAM      0x01
+#define RESET_IWRAM      0x02
+#define RESET_PALETTE    0x04
+#define RESET_VRAM       0x08
+#define RESET_OAM        0x10
+#define RESET_SIO_REGS   0x20
+#define RESET_SOUND_REGS 0x40
+#define RESET_REGS       0x80
+#define RESET_ALL        0xFF
+
+void SoftReset(u32 resetFlags);
+
+void RegisterRamReset(u32 resetFlags);
+
 #define CPU_SET_SRC_FIXED 0x01000000
 #define CPU_SET_16BIT     0x00000000
 #define CPU_SET_32BIT     0x04000000
 
-extern void CpuSet(void *src, void *dest, u32 control);
+void CpuSet(void *src, void *dest, u32 control);
 
-extern void VBlankIntrWait(void);
+void VBlankIntrWait(void);
 
 #endif // GUARD_GBA_SYSCALL_H
diff --git a/src/m4a_2.c b/src/m4a_2.c
index 56487808c..2056f805a 100644
--- a/src/m4a_2.c
+++ b/src/m4a_2.c
@@ -4,14 +4,13 @@
 
 BSS_CODE ALIGNED(4) char SoundMainRAM_Buffer[0x800] = {0};
 
-IWRAM_DATA struct SoundInfo gSoundInfo = {0};
-IWRAM_DATA struct PokemonCrySong gPokemonCrySongs[MAX_POKEMON_CRIES] = {0};
-IWRAM_DATA u8 gUnused_3006FE8[8] = {0}; // padding for alignment
-IWRAM_DATA struct MusicPlayerInfo gPokemonCryMusicPlayers[MAX_POKEMON_CRIES] = {0};
-IWRAM_DATA void *gMPlayJumpTable[36] = {0};
-IWRAM_DATA struct CgbChannel gCgbChans[4] = {0};
-IWRAM_DATA struct MusicPlayerTrack gPokemonCryTracks[MAX_POKEMON_CRIES * 2] = {0};
-IWRAM_DATA struct PokemonCrySong gPokemonCrySong = {0};
+COMM_4(struct SoundInfo gSoundInfo)
+COMM_4(struct PokemonCrySong gPokemonCrySongs[MAX_POKEMON_CRIES])
+COMM_4(struct MusicPlayerInfo gPokemonCryMusicPlayers[MAX_POKEMON_CRIES])
+COMM_4(void *gMPlayJumpTable[36])
+COMM_4(struct CgbChannel gCgbChans[4])
+COMM_4(struct MusicPlayerTrack gPokemonCryTracks[MAX_POKEMON_CRIES * 2])
+COMM_4(struct PokemonCrySong gPokemonCrySong)
 
 u32 MidiKeyToFreq(struct WaveData *wav, u8 key, u8 fineAdjust)
 {