Decompile MI_dma.c

2 files changed, 66 insertions, 0 deletions

diff --git a/arm7/lib/include/MI_dma.h b/arm7/lib/include/MI_dma.h
new file mode 100644
index 00000000..4bae3663
--- /dev/null
+++ b/arm7/lib/include/MI_dma.h
@@ -0,0 +1,30 @@
+#ifndef GUARD_MI_DMA_H
+#define GUARD_MI_DMA_H
+
+#include "nitro/types.h"
+
+#define REG_ADDR_DMA0SAD 0x040000b0
+
+#define DMA_DEST_INC      0x0000
+#define DMA_DEST_DEC      0x0020
+#define DMA_DEST_FIXED    0x0040
+#define DMA_DEST_RELOAD   0x0060
+#define DMA_SRC_INC       0x0000
+#define DMA_SRC_DEC       0x0080
+#define DMA_SRC_FIXED     0x0100
+#define DMA_REPEAT        0x0200
+#define DMA_16BIT         0x0000
+#define DMA_32BIT         0x0400
+#define DMA_DREQ_ON       0x0800
+#define DMA_START_NOW     0x0000
+#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
+
+void MI_StopDma(u32 channel);
+void MI_WaitDma(u32 channel);
+
+#endif
diff --git a/arm7/lib/src/MI_dma.c b/arm7/lib/src/MI_dma.c
new file mode 100644
index 00000000..fc2ff0c9
--- /dev/null
+++ b/arm7/lib/src/MI_dma.c
@@ -0,0 +1,36 @@
+#include "function_target.h"
+#include "MI_dma.h"
+#include "OS_system.h"
+
+ARM_FUNC void MI_WaitDma(u32 channel) {
+    OSIntrMode mode = OS_DisableInterrupts();
+    vu32 * addr = (vu32 *)(REG_ADDR_DMA0SAD + (channel * 3 + 2) * 4);
+    while(addr[0] & 0x80000000) ;
+    if (channel == 0) {
+        addr = (vu32 *)(REG_ADDR_DMA0SAD + channel * 12);
+        addr[0] = 0;
+        addr[1] = 0;
+        addr[2] = 0x81400001;
+    }
+    mode = OS_RestoreInterrupts(mode);
+}
+
+ARM_FUNC void MI_StopDma(u32 channel) {
+    OSIntrMode mode = OS_DisableInterrupts();
+    vu16 * addr = (vu16 *)(REG_ADDR_DMA0SAD + (channel * 6 + 5) * 2);
+    addr[0] &= ~(DMA_START_MASK | DMA_REPEAT);
+    addr[0] &= ~DMA_ENABLE;
+    {
+        s32 dummy = addr[0];
+    }
+    {
+        s32 dummy = addr[0];
+    }
+    if (channel == 0) {
+        vu32 * addr32 = (vu32 *)(REG_ADDR_DMA0SAD + channel * 12);
+        addr32[0] = 0;
+        addr32[1] = 0;
+        addr32[2] = 0x81400001;
+    }
+    mode = OS_RestoreInterrupts(mode);
+}