Support basic linked elements

include/PSX/System/IOPorts/dma_io.hpp

@@ -68,6 +68,10 @@ namespace JabyEngine {
                 return Self{0x01000201};
             }
 
+            static constexpr Self StartGPULinked() {
+                return Self{0x01000401};
+            }
+
             static constexpr Self StartCDROM() {
                 return Self{0x11000000};
             }