Full savestating to memory

include/dma.h

@@ -2,6 +2,20 @@
 
 #include <common.h>
 
+typedef struct {
+    bool active;
+    u8 byte;
+    u8 value;
+    u8 start_delay;
+} dma_context;
+
+typedef struct {
+    dma_context ctx;
+} dma_state;
+
+void dma_save_state(dma_state*);
+void dma_load_state(const dma_state*);
+
 void dma_start(u8 start);
 void dma_tick();