diff --git a/src/backend/Core.cpp b/src/backend/Core.cpp
index 9df946cc..ee45b11e 100644
--- a/src/backend/Core.cpp
+++ b/src/backend/Core.cpp
@@ -3,18 +3,6 @@
 #include <ParallelRDPWrapper.hpp>
 
 namespace n64 {
-u32 extraCycles = 0;
-
-void CpuStall(u32 cycles) {
-  extraCycles += cycles;
-}
-
-u32 PopStalledCycles() {
-  u32 ret = extraCycles;
-  extraCycles = 0;
-  return ret;
-}
-
 Core::Core() : cpu(std::make_unique<Interpreter>()) {}
 
 void Core::Stop() {
@@ -71,7 +59,7 @@ void Core::Run(float volumeL, float volumeR) {
 
       for(; cycles < mem.mmio.vi.cyclesPerHalfline; cycles++, frameCycles++) {
         u32 taken = cpu->Step();
-        taken += PopStalledCycles();
+        taken += regs.PopStalledCycles();
         static u32 cpuSteps = 0;
         cpuSteps += taken;
         if(mmio.rsp.spStatus.halt) {
@@ -91,7 +79,7 @@ void Core::Run(float volumeL, float volumeR) {
 
         cycles += taken;
         frameCycles += taken;
-        scheduler.Tick(taken, mem, regs);
+        scheduler.Tick(taken, mem);
       }
 
       cycles -= mmio.vi.cyclesPerHalfline;
@@ -101,8 +89,8 @@ void Core::Run(float volumeL, float volumeR) {
       mmio.mi.InterruptRaise(MI::Interrupt::VI);
     }
 
-    mmio.ai.Step(cpu->mem, regs, frameCycles, volumeL, volumeR);
-    scheduler.Tick(frameCycles, mem, regs);
+    mmio.ai.Step(frameCycles, volumeL, volumeR);
+    scheduler.Tick(frameCycles, mem);
   }
 }
 
diff --git a/src/backend/Core.hpp b/src/backend/Core.hpp
index f6968135..b0639aa9 100644
--- a/src/backend/Core.hpp
+++ b/src/backend/Core.hpp
@@ -30,8 +30,4 @@ struct Core {
   size_t memSize{}, cpuSize{}, verSize{};
   int slot = 0;
 };
-
-extern u32 extraCycles;
-void CpuStall(u32 cycles);
-u32 PopStalledCycles();
 }
diff --git a/src/backend/Scheduler.cpp b/src/backend/Scheduler.cpp
index 13f09424..f9664ff1 100644
--- a/src/backend/Scheduler.cpp
+++ b/src/backend/Scheduler.cpp
@@ -25,7 +25,7 @@ u64 Scheduler::Remove(EventType type) {
   return 0;
 }
 
-void Scheduler::Tick(u64 t, n64::Mem& mem, n64::Registers& regs) {
+void Scheduler::Tick(u64 t, n64::Mem& mem) {
   ticks += t;
   n64::MI& mi = mem.mmio.mi;
   n64::SI& si = mem.mmio.si;
@@ -34,7 +34,7 @@ void Scheduler::Tick(u64 t, n64::Mem& mem, n64::Registers& regs) {
   while(ticks >= events.top().time) {
     switch(auto type = events.top().type) {
       case SI_DMA:
-        si.DMA(mem, regs);
+        si.DMA();
         break;
       case PI_DMA_COMPLETE:
         mi.InterruptRaise(n64::MI::Interrupt::PI);
diff --git a/src/backend/Scheduler.hpp b/src/backend/Scheduler.hpp
index 4dc4c840..d0565d4d 100644
--- a/src/backend/Scheduler.hpp
+++ b/src/backend/Scheduler.hpp
@@ -53,7 +53,7 @@ struct Scheduler {
   void EnqueueRelative(u64, EventType);
   void EnqueueAbsolute(u64, EventType);
   u64 Remove(EventType);
-  void Tick(u64 t, n64::Mem&, n64::Registers&);
+  void Tick(u64 t, n64::Mem&);
 
   IterableEvents events;
   u64 ticks = 0;
diff --git a/src/backend/core/MMIO.cpp b/src/backend/core/MMIO.cpp
index aacf8974..31fa7a28 100644
--- a/src/backend/core/MMIO.cpp
+++ b/src/backend/core/MMIO.cpp
@@ -1,7 +1,5 @@
 #include <core/MMIO.hpp>
-#include <log.hpp>
 #include <core/Mem.hpp>
-#include <core/registers/Registers.hpp>
 
 namespace n64 {
 void MMIO::Reset() {
@@ -22,24 +20,24 @@ u32 MMIO::Read(u32 addr) {
     case MI_REGION: return mi.Read(addr);
     case VI_REGION: return vi.Read(addr);
     case AI_REGION: return ai.Read(addr);
-    case PI_REGION: return pi.Read(mi, addr);
+    case PI_REGION: return pi.Read(addr);
     case RI_REGION: return ri.Read(addr);
-    case SI_REGION: return si.Read(mi, addr);
+    case SI_REGION: return si.Read(addr);
     default:
       Util::panic("Unhandled mmio read at addr {:08X}", addr);
   }
 }
 
-void MMIO::Write(Mem& mem, Registers& regs, u32 addr, u32 val) {
+void MMIO::Write(u32 addr, u32 val) {
   switch (addr) {
     case RSP_REGION: rsp.Write(addr, val); break;
-    case RDP_REGION: rdp.Write(mi, regs, rsp, addr, val); break;
-    case MI_REGION: mi.Write(regs, addr, val); break;
-    case VI_REGION: vi.Write(mi, regs, addr, val); break;
-    case AI_REGION: ai.Write(mem, regs, addr, val); break;
-    case PI_REGION: pi.Write(mem, regs, addr, val); break;
+    case RDP_REGION: rdp.Write(addr, val); break;
+    case MI_REGION: mi.Write(addr, val); break;
+    case VI_REGION: vi.Write(addr, val); break;
+    case AI_REGION: ai.Write(addr, val); break;
+    case PI_REGION: pi.Write(addr, val); break;
     case RI_REGION: ri.Write(addr, val); break;
-    case SI_REGION: si.Write(mem, regs, addr, val); break;
+    case SI_REGION: si.Write(addr, val); break;
     default:
       Util::panic("Unhandled mmio write at addr {:08X} with val {:08X}", addr, val);
   }
diff --git a/src/backend/core/MMIO.hpp b/src/backend/core/MMIO.hpp
index f9ce0c94..880802ac 100644
--- a/src/backend/core/MMIO.hpp
+++ b/src/backend/core/MMIO.hpp
@@ -13,7 +13,7 @@ struct Mem;
 struct Registers;
 
 struct MMIO {
-  MMIO(Mem& mem, Registers& regs) : mi(regs), si(mem, regs), rsp(mem, regs) {}
+  MMIO(Mem& mem, Registers& regs) : vi(mem, regs), mi(regs), ai(mem, regs), pi(mem, regs), si(mem, regs), rsp(mem, regs), rdp(mem, regs) {}
   void Reset();
 
   VI vi;
@@ -26,7 +26,7 @@ struct MMIO {
   RDP rdp;
 
   u32 Read(u32);
-  void Write(Mem&, Registers&, u32, u32);
+  void Write(u32, u32);
   std::vector<u8> Serialize();
   void Deserialize(const std::vector<u8>&);
 };
diff --git a/src/backend/core/Mem.cpp b/src/backend/core/Mem.cpp
index d8908bf7..51293c90 100644
--- a/src/backend/core/Mem.cpp
+++ b/src/backend/core/Mem.cpp
@@ -193,7 +193,7 @@ template<> u8 Mem::Read(n64::Registers &regs, u32 paddr) {
         return src[BYTE_ADDRESS(paddr & 0xfff)];
       }
       case REGION_CART:
-        return mmio.pi.BusRead<u8, false>(*this, paddr);
+        return mmio.pi.BusRead<u8, false>(paddr);
       case 0x04040000 ... 0x040FFFFF:
       case 0x04100000 ... 0x041FFFFF:
       case 0x04600000 ... 0x048FFFFF:
@@ -238,7 +238,7 @@ template<> u16 Mem::Read(n64::Registers &regs, u32 paddr) {
       case MMIO_REGION:
         return mmio.Read(paddr);
       case REGION_CART:
-        return mmio.pi.BusRead<u16, false>(*this, paddr);
+        return mmio.pi.BusRead<u16, false>(paddr);
       case PIF_ROM_REGION:
         return Util::ReadAccess<u16>(si.pif.bootrom, HALF_ADDRESS(paddr) - PIF_ROM_REGION_START);
       case PIF_RAM_REGION:
@@ -273,7 +273,7 @@ template<> u32 Mem::Read(n64::Registers &regs, u32 paddr) {
       case MMIO_REGION:
         return mmio.Read(paddr);
       case REGION_CART:
-        return mmio.pi.BusRead<u32, false>(*this, paddr);
+        return mmio.pi.BusRead<u32, false>(paddr);
       case PIF_ROM_REGION:
         return Util::ReadAccess<u32>(si.pif.bootrom, paddr - PIF_ROM_REGION_START);
       case PIF_RAM_REGION:
@@ -305,7 +305,7 @@ template<> u64 Mem::Read(n64::Registers &regs, u32 paddr) {
       case MMIO_REGION:
         return mmio.Read(paddr);
       case REGION_CART:
-        return mmio.pi.BusRead<u64, false>(*this, paddr);
+        return mmio.pi.BusRead<u64, false>(paddr);
       case PIF_ROM_REGION:
         return Util::ReadAccess<u64>(si.pif.bootrom, paddr - PIF_ROM_REGION_START);
       case PIF_RAM_REGION:
@@ -342,7 +342,7 @@ template<> void Mem::Write<u8>(Registers& regs, u32 paddr, u32 val) {
       } break;
       case REGION_CART:
         Util::trace("BusWrite<u8> @ {:08X} = {:02X}", paddr, val);
-        mmio.pi.BusWrite<u8, false>(*this, paddr, val);
+        mmio.pi.BusWrite<u8, false>(paddr, val);
         break;
       case MMIO_REGION:
         Util::panic("MMIO Write<u8>!");
@@ -387,7 +387,7 @@ template<> void Mem::Write<u16>(Registers& regs, u32 paddr, u32 val) {
       } break;
       case REGION_CART:
         Util::trace("BusWrite<u8> @ {:08X} = {:04X}", paddr, val);
-        mmio.pi.BusWrite<u16, false>(*this, paddr, val);
+        mmio.pi.BusWrite<u16, false>(paddr, val);
         break;
       case MMIO_REGION:
         Util::panic("MMIO Write<u16>!");
@@ -430,10 +430,10 @@ template<> void Mem::Write<u32>(Registers& regs, u32 paddr, u32 val) {
       } break;
       case REGION_CART:
         Util::trace("BusWrite<u8> @ {:08X} = {:08X}", paddr, val);
-        mmio.pi.BusWrite<u32, false>(*this, paddr, val);
+        mmio.pi.BusWrite<u32, false>(paddr, val);
         break;
       case MMIO_REGION:
-        mmio.Write(*this, regs, paddr, val);
+        mmio.Write(paddr, val);
         break;
       case PIF_RAM_REGION:
         Util::WriteAccess<u32>(si.pif.ram, paddr - PIF_RAM_REGION_START, htobe32(val));
@@ -470,7 +470,7 @@ void Mem::Write(Registers& regs, u32 paddr, u64 val) {
       } break;
       case REGION_CART:
         Util::trace("BusWrite<u8> @ {:08X} = {:016X}", paddr, val);
-        mmio.pi.BusWrite<false>(*this, paddr, val);
+        mmio.pi.BusWrite<false>(paddr, val);
         break;
       case MMIO_REGION:
         Util::panic("MMIO Write!");
diff --git a/src/backend/core/RDP.cpp b/src/backend/core/RDP.cpp
index a2ca1888..16dfd8be 100644
--- a/src/backend/core/RDP.cpp
+++ b/src/backend/core/RDP.cpp
@@ -5,7 +5,7 @@
 #include <core/mmio/Interrupt.hpp>
 
 namespace n64 {
-RDP::RDP() {
+RDP::RDP(Mem& mem, Registers& regs) : mem(mem), regs(regs) {
   rdram.resize(RDRAM_SIZE);
   memset(cmd_buf, 0, 0x100000);
   dpc.status.raw = 0x80;
@@ -40,17 +40,17 @@ auto RDP::Read(u32 addr) const -> u32 {
   }
 }
 
-void RDP::Write(MI& mi, Registers& regs, RSP& rsp, u32 addr, u32 val) {
+void RDP::Write(u32 addr, u32 val) {
   switch(addr) {
     case 0x04100000: WriteStart(val); break;
-    case 0x04100004: WriteEnd(mi, regs, rsp, val); break;
-    case 0x0410000C: WriteStatus(mi, regs, rsp, val); break;
+    case 0x04100004: WriteEnd(val); break;
+    case 0x0410000C: WriteStatus(val); break;
     default:
       Util::panic("Unhandled DP Command Registers write (addr: {:08X}, val: {:08X})", addr, val);
   }
 }
 
-void RDP::WriteStatus(MI& mi, Registers& regs, RSP& rsp, u32 val) {
+void RDP::WriteStatus(u32 val) {
   DPCStatusWrite temp{};
   temp.raw = val;
 
@@ -69,7 +69,7 @@ void RDP::WriteStatus(MI& mi, Registers& regs, RSP& rsp, u32 val) {
   CLEAR_SET(dpc.status.tmemBusy, temp.clearTmem, false);
 
   if(!dpc.status.freeze) {
-    RunCommand(mi, regs, rsp);
+    RunCommand();
   }
 }
 /*
@@ -114,7 +114,7 @@ FORCE_INLINE void logCommand(u8 cmd) {
 }
  */
 
-void RDP::RunCommand(MI& mi, Registers& regs, RSP& rsp) {
+void RDP::RunCommand() {
   if (dpc.status.freeze) {
     return;
   }
@@ -138,7 +138,7 @@ void RDP::RunCommand(MI& mi, Registers& regs, RSP& rsp) {
 
     if (dpc.status.xbusDmemDma) {
       for (int i = 0; i < len; i += 4) {
-        u32 cmd = Util::ReadAccess<u32>(rsp.dmem, (current + i) & 0xFFF);
+        u32 cmd = Util::ReadAccess<u32>(mem.mmio.rsp.dmem, (current + i) & 0xFFF);
         cmd_buf[remaining_cmds + (i >> 2)] = cmd;
       }
     } else {
@@ -181,7 +181,7 @@ void RDP::RunCommand(MI& mi, Registers& regs, RSP& rsp) {
       }
 
       if (cmd == 0x29) {
-        OnFullSync(mi, regs);
+        OnFullSync();
       }
 
       buf_index += cmd_len;
@@ -198,12 +198,12 @@ void RDP::RunCommand(MI& mi, Registers& regs, RSP& rsp) {
   dpc.status.cbufReady = true;
 }
 
-void RDP::OnFullSync(MI& mi, Registers& regs) {
+void RDP::OnFullSync() {
   ParallelRdpOnFullSync();
 
   dpc.status.pipeBusy = false;
   dpc.status.startGclk = false;
   dpc.status.cbufReady = false;
-  mi.InterruptRaise(MI::Interrupt::DP);
+  mem.mmio.mi.InterruptRaise(MI::Interrupt::DP);
 }
 }
diff --git a/src/backend/core/RDP.hpp b/src/backend/core/RDP.hpp
index 6bf0bec0..7bc78a82 100644
--- a/src/backend/core/RDP.hpp
+++ b/src/backend/core/RDP.hpp
@@ -5,7 +5,7 @@
 namespace n64 {
 
 struct RSP;
-struct MI;
+struct Mem;
 struct Registers;
 
 union DPCStatusWrite {
@@ -54,15 +54,15 @@ struct RDP {
   DPC dpc{};
   u32 cmd_buf[0xFFFFF]{};
 
-  RDP();
+  RDP(Mem&, Registers&);
   void Reset();
 
   std::vector<u8> rdram{};
   [[nodiscard]] auto Read(u32 addr) const -> u32;
-  void Write(MI& mi, Registers& regs, RSP& rsp, u32 addr, u32 val);
-  void WriteStatus(MI& mi, Registers& regs, RSP& rsp, u32 val);
-  void RunCommand(MI& mi, Registers& regs, RSP& rsp);
-  void OnFullSync(MI& mi, Registers& regs);
+  void Write(u32 addr, u32 val);
+  void WriteStatus(u32 val);
+  void RunCommand();
+  void OnFullSync();
 
   FORCE_INLINE void WriteStart(u32 val) {
     if(!dpc.status.startValid) {
@@ -71,13 +71,16 @@ struct RDP {
     dpc.status.startValid = true;
   }
 
-  FORCE_INLINE void WriteEnd(MI& mi, Registers& regs, RSP& rsp, u32 val) {
+  FORCE_INLINE void WriteEnd(u32 val) {
     dpc.end = val & 0xFFFFF8;
     if(dpc.status.startValid) {
       dpc.current = dpc.start;
       dpc.status.startValid = false;
     }
-    RunCommand(mi, regs, rsp);
+    RunCommand();
   }
+private:
+  Mem& mem;
+  Registers& regs;
 };
 } // backend
diff --git a/src/backend/core/RSP.cpp b/src/backend/core/RSP.cpp
index 55015874..cc454e77 100644
--- a/src/backend/core/RSP.cpp
+++ b/src/backend/core/RSP.cpp
@@ -110,26 +110,26 @@ void RSP::WriteStatus(u32 value) {
   CLEAR_SET(spStatus.signal7, write.clearSignal7, write.setSignal7);
 }
 
-void RSP::Write(u32 addr, u32 value) {
+void RSP::Write(u32 addr, u32 val) {
   switch (addr) {
-    case 0x04040000: spDMASPAddr.raw = value & 0x1FF8; break;
-    case 0x04040004: spDMADRAMAddr.raw = value & 0xFFFFF8; break;
+    case 0x04040000: spDMASPAddr.raw = val & 0x1FF8; break;
+    case 0x04040004: spDMADRAMAddr.raw = val & 0xFFFFF8; break;
     case 0x04040008: {
-      spDMALen.raw = value;
+      spDMALen.raw = val;
       DMAtoRSP(mem.GetRDRAM());
     } break;
     case 0x0404000C: {
-      spDMALen.raw = value;
+      spDMALen.raw = val;
       DMAtoRDRAM(mem.GetRDRAM());
     } break;
-    case 0x04040010: WriteStatus(value); break;
+    case 0x04040010: WriteStatus(val); break;
     case 0x0404001C: ReleaseSemaphore(); break;
     case 0x04080000:
       if(spStatus.halt) {
-        SetPC(value);
+        SetPC(val);
       } break;
     default:
-      Util::panic("Unimplemented SP register write {:08X}, val: {:08X}", addr, value);
+      Util::panic("Unimplemented SP register write {:08X}, val: {:08X}", addr, val);
   }
 }
 
diff --git a/src/backend/core/RSP.hpp b/src/backend/core/RSP.hpp
index 223737cf..1c4c9e46 100644
--- a/src/backend/core/RSP.hpp
+++ b/src/backend/core/RSP.hpp
@@ -126,7 +126,7 @@ struct RSP {
     Exec(instr);
   }
   auto Read(u32 addr) -> u32;
-  void Write(u32 addr, u32 value);
+  void Write(u32 addr, u32 val);
   void Exec(u32 instr);
   SPStatus spStatus{};
   u16 oldPC{}, pc{}, nextPC{};
diff --git a/src/backend/core/mmio/AI.cpp b/src/backend/core/mmio/AI.cpp
index 86a31094..86a6c445 100644
--- a/src/backend/core/mmio/AI.cpp
+++ b/src/backend/core/mmio/AI.cpp
@@ -4,6 +4,8 @@
 #include <core/registers/Registers.hpp>
 
 namespace n64 {
+AI::AI(Mem &mem, Registers &regs) : mem(mem), regs(regs) { }
+
 void AI::Reset() {
   dmaEnable = false;
   dacRate = 0;
@@ -33,7 +35,7 @@ auto AI::Read(u32 addr) const -> u32 {
   return dmaLen[0];
 }
 
-void AI::Write(Mem& mem, Registers& regs, u32 addr, u32 val) {
+void AI::Write(u32 addr, u32 val) {
   switch(addr) {
     case 0x04500000:
       if(dmaCount < 2) {
@@ -72,7 +74,7 @@ void AI::Write(Mem& mem, Registers& regs, u32 addr, u32 val) {
   }
 }
 
-void AI::Step(Mem& mem, Registers& regs, u32 cpuCycles, float volumeL, float volumeR) {
+void AI::Step(u32 cpuCycles, float volumeL, float volumeR) {
   cycles += cpuCycles;
   while(cycles > dac.period) {
     if (dmaCount == 0) {
diff --git a/src/backend/core/mmio/AI.hpp b/src/backend/core/mmio/AI.hpp
index d633d24b..3f522216 100644
--- a/src/backend/core/mmio/AI.hpp
+++ b/src/backend/core/mmio/AI.hpp
@@ -8,11 +8,11 @@ struct Mem;
 struct Registers;
 
 struct AI {
-  AI() = default;
+  AI(Mem&, Registers& regs);
   void Reset();
   auto Read(u32) const -> u32;
-  void Write(Mem&, Registers&, u32, u32);
-  void Step(Mem&, Registers&, u32, float, float);
+  void Write(u32, u32);
+  void Step(u32, float, float);
   bool dmaEnable{};
   u16 dacRate{};
   u8 bitrate{};
@@ -28,5 +28,8 @@ struct AI {
     u32 period{N64_CPU_FREQ / freq};
     u32 precision{16};
   } dac;
+private:
+  Mem& mem;
+  Registers& regs;
 };
 }
\ No newline at end of file
diff --git a/src/backend/core/mmio/MI.cpp b/src/backend/core/mmio/MI.cpp
index 9c818629..4fb85ff9 100644
--- a/src/backend/core/mmio/MI.cpp
+++ b/src/backend/core/mmio/MI.cpp
@@ -27,7 +27,7 @@ auto MI::Read(u32 paddr) const -> u32 {
   }
 }
 
-void MI::Write(Registers& regs, u32 paddr, u32 val) {
+void MI::Write(u32 paddr, u32 val) {
   switch(paddr & 0xF) {
     case 0x0:
       miMode &= 0xFFFFFF80;
diff --git a/src/backend/core/mmio/MI.hpp b/src/backend/core/mmio/MI.hpp
index 73d67ae1..cc6f398d 100644
--- a/src/backend/core/mmio/MI.hpp
+++ b/src/backend/core/mmio/MI.hpp
@@ -26,7 +26,7 @@ struct MI {
   MI(Registers&);
   void Reset();
   [[nodiscard]] auto Read(u32) const -> u32;
-  void Write(Registers& regs, u32, u32);
+  void Write(u32, u32);
   void InterruptRaise(Interrupt intr);
   void InterruptLower(Interrupt intr);
   void UpdateInterrupt();
diff --git a/src/backend/core/mmio/PI.cpp b/src/backend/core/mmio/PI.cpp
index 34dc7da2..33aabf8e 100644
--- a/src/backend/core/mmio/PI.cpp
+++ b/src/backend/core/mmio/PI.cpp
@@ -4,7 +4,7 @@
 #include <Scheduler.hpp>
 
 namespace n64 {
-PI::PI() {
+PI::PI(Mem& mem, Registers& regs) : mem(mem), regs(regs) {
   Reset();
 }
 
@@ -42,13 +42,13 @@ bool PI::WriteLatch(u32 value) {
 bool PI::ReadLatch() {
   if (ioBusy) [[unlikely]] {
     ioBusy = false;
-    CpuStall(scheduler.Remove(PI_BUS_WRITE_COMPLETE));
+    regs.CpuStall(scheduler.Remove(PI_BUS_WRITE_COMPLETE));
     return false;
   }
   return true;
 }
 
-template<> auto PI::BusRead<u8, true>(Mem& mem, u32 addr) -> u8 {
+template<> auto PI::BusRead<u8, true>(u32 addr) -> u8 {
   switch (addr) {
     case REGION_PI_UNKNOWN:
       Util::panic("Reading byte from address 0x{:08X} in unsupported region: REGION_PI_UNKNOWN - This is the N64DD, returning FF because it is not emulated", addr);
@@ -73,7 +73,7 @@ template<> auto PI::BusRead<u8, true>(Mem& mem, u32 addr) -> u8 {
   }
 }
 
-template<> auto PI::BusRead<u8, false>(Mem& mem, u32 addr) -> u8 {
+template<> auto PI::BusRead<u8, false>(u32 addr) -> u8 {
   if (!ReadLatch()) [[unlikely]] {
     return latch >> 24;
   }
@@ -103,7 +103,7 @@ template<> auto PI::BusRead<u8, false>(Mem& mem, u32 addr) -> u8 {
   }
 }
 
-template<> void PI::BusWrite<u8, true>(Mem& mem, u32 addr, u32 val) {
+template<> void PI::BusWrite<u8, true>(u32 addr, u32 val) {
   switch (addr) {
     case REGION_PI_UNKNOWN:
       Util::panic("Writing byte 0x{:02X} to address 0x{:08X} in unsupported region: REGION_PI_UNKNOWN", val, addr);
@@ -127,17 +127,17 @@ template<> void PI::BusWrite<u8, true>(Mem& mem, u32 addr, u32 val) {
   }
 }
 
-template<> void PI::BusWrite<u8, false>(Mem& mem, u32 addr, u32 val) {
+template<> void PI::BusWrite<u8, false>(u32 addr, u32 val) {
   u8 latch_shift = 24 - (addr & 1) * 8;
 
   if (!WriteLatch(val << latch_shift) && addr != 0x05000020) [[unlikely]] {
     return;
   }
 
-  BusWrite<u8, true>(mem, addr, val);
+  BusWrite<u8, true>(addr, val);
 }
 
-template <> auto PI::BusRead<u16, false>(Mem& mem, u32 addr) -> u16 {
+template <> auto PI::BusRead<u16, false>(u32 addr) -> u16 {
   if (!ReadLatch()) [[unlikely]] {
     return latch >> 16;
   }
@@ -164,11 +164,11 @@ template <> auto PI::BusRead<u16, false>(Mem& mem, u32 addr) -> u16 {
   }
 }
 
-template <> auto PI::BusRead<u16, true>(Mem& mem, u32 addr) -> u16 {
-  return BusRead<u16, false>(mem, addr);
+template <> auto PI::BusRead<u16, true>(u32 addr) -> u16 {
+  return BusRead<u16, false>(addr);
 }
 
-template <> void PI::BusWrite<u16, false>(Mem&, u32 addr, u32 val) {
+template <> void PI::BusWrite<u16, false>(u32 addr, u32 val) {
   if (!WriteLatch(val << 16)) [[unlikely]] {
     return;
   }
@@ -190,11 +190,11 @@ template <> void PI::BusWrite<u16, false>(Mem&, u32 addr, u32 val) {
   }
 }
 
-template <> void PI::BusWrite<u16, true>(Mem& mem, u32 addr, u32 val) {
-  BusWrite<u16, false>(mem, addr, val);
+template <> void PI::BusWrite<u16, true>(u32 addr, u32 val) {
+  BusWrite<u16, false>(addr, val);
 }
 
-template <> auto PI::BusRead<u32, false>(Mem& mem, u32 addr) -> u32 {
+template <> auto PI::BusRead<u32, false>(u32 addr) -> u32 {
   if (!ReadLatch()) [[unlikely]] {
     return latch;
   }
@@ -232,11 +232,11 @@ template <> auto PI::BusRead<u32, false>(Mem& mem, u32 addr) -> u32 {
   }
 }
 
-template <> auto PI::BusRead<u32, true>(Mem& mem, u32 addr) -> u32 {
-  return BusRead<u32, false>(mem, addr);
+template <> auto PI::BusRead<u32, true>(u32 addr) -> u32 {
+  return BusRead<u32, false>(addr);
 }
 
-template <> void PI::BusWrite<u32, false>(Mem& mem, u32 addr, u32 val) {
+template <> void PI::BusWrite<u32, false>(u32 addr, u32 val) {
   switch (addr) {
     case REGION_PI_UNKNOWN:
       if (!WriteLatch(val)) [[unlikely]] {
@@ -293,11 +293,11 @@ template <> void PI::BusWrite<u32, false>(Mem& mem, u32 addr, u32 val) {
 }
 
 template <>
-void PI::BusWrite<u32, true>(Mem& mem, u32 addr, u32 val) {
-  BusWrite<u32, false>(mem, addr, val);
+void PI::BusWrite<u32, true>(u32 addr, u32 val) {
+  BusWrite<u32, false>(addr, val);
 }
 
-template <> auto PI::BusRead<u64, false>(Mem& mem, u32 addr) -> u64 {
+template <> auto PI::BusRead<u64, false>(u32 addr) -> u64 {
   if (!ReadLatch()) [[unlikely]] {
     return (u64)latch << 32;
   }
@@ -323,11 +323,11 @@ template <> auto PI::BusRead<u64, false>(Mem& mem, u32 addr) -> u64 {
   }
 }
 
-template <> auto PI::BusRead<u64, true>(Mem& mem, u32 addr) -> u64 {
-  return BusRead<u64, false>(mem, addr);
+template <> auto PI::BusRead<u64, true>(u32 addr) -> u64 {
+  return BusRead<u64, false>(addr);
 }
 
-template <> void PI::BusWrite<false>(Mem&, u32 addr, u64 val) {
+template <> void PI::BusWrite<false>(u32 addr, u64 val) {
   if (!WriteLatch(val >> 32)) [[unlikely]] {
     return;
   }
@@ -349,11 +349,11 @@ template <> void PI::BusWrite<false>(Mem&, u32 addr, u64 val) {
   }
 }
 
-template <> void PI::BusWrite<true>(Mem& mem, u32 addr, u64 val) {
-  BusWrite<false>(mem, addr, val);
+template <> void PI::BusWrite<true>(u32 addr, u64 val) {
+  BusWrite<false>(addr, val);
 }
 
-auto PI::Read(MI& mi, u32 addr) const -> u32 {
+auto PI::Read(u32 addr) const -> u32 {
   switch(addr) {
     case 0x04600000: return dramAddr;
     case 0x04600004: return cartAddr;
@@ -364,7 +364,7 @@ auto PI::Read(MI& mi, u32 addr) const -> u32 {
       value |= (dmaBusy << 0); // Is PI DMA active? No, because it's instant
       value |= (ioBusy << 1); // Is PI IO busy? No, because it's instant
       value |= (0 << 2); // PI IO error?
-      value |= (mi.miIntr.pi << 3); // PI interrupt?
+      value |= (mem.mmio.mi.miIntr.pi << 3); // PI interrupt?
       return value;
     }
     case 0x04600014: return piBsdDom1Lat;
@@ -427,7 +427,7 @@ u32 PI::AccessTiming(u8 domain, u32 length) const {
   return cycles * 1.5; // Converting RCP clock speed to CPU clock speed
 }
 
-void PI::Write(Mem& mem, Registers& regs, u32 addr, u32 val) {
+void PI::Write(u32 addr, u32 val) {
   MI& mi = mem.mmio.mi;
   switch(addr) {
     case 0x04600000: dramAddr = val & 0xFFFFFF; break;
@@ -444,7 +444,7 @@ void PI::Write(Mem& mem, Registers& regs, u32 addr, u32 val) {
         Util::panic("PI DMA RDRAM->CART ADDRESS TOO HIGH");
       }
       for (int i = 0; i < len; i++) {
-        BusWrite<u8, true>(mem, cartAddrInternal + i, mem.mmio.rdp.rdram[BYTE_ADDRESS(dramAddrInternal + i) & RDRAM_DSIZE]);
+        BusWrite<u8, true>(cartAddrInternal + i, mem.mmio.rdp.rdram[BYTE_ADDRESS(dramAddrInternal + i) & RDRAM_DSIZE]);
       }
       Util::trace("PI DMA from RDRAM to CARTRIDGE (size: {} B, {:08X} to {:08X})", len, dramAddr, cartAddr);
       dmaBusy = true;
@@ -465,7 +465,7 @@ void PI::Write(Mem& mem, Registers& regs, u32 addr, u32 val) {
       }
 
       for(u32 i = 0; i < len; i++) {
-        mem.mmio.rdp.rdram[BYTE_ADDRESS(dramAddrInternal + i) & RDRAM_DSIZE] = BusRead<u8, true>(mem, cartAddrInternal + i);
+        mem.mmio.rdp.rdram[BYTE_ADDRESS(dramAddrInternal + i) & RDRAM_DSIZE] = BusRead<u8, true>(cartAddrInternal + i);
       }
       dmaBusy = true;
       Util::trace("PI DMA from CARTRIDGE to RDRAM (size: {} B, {:08X} to {:08X})", len, cartAddr, dramAddr);
diff --git a/src/backend/core/mmio/PI.hpp b/src/backend/core/mmio/PI.hpp
index 1d31b381..d1132cb0 100644
--- a/src/backend/core/mmio/PI.hpp
+++ b/src/backend/core/mmio/PI.hpp
@@ -8,18 +8,18 @@ struct Mem;
 struct Registers;
 
 struct PI {
-  PI();
+  PI(Mem&, Registers&);
   void Reset();
-  auto Read(MI&, u32) const -> u32;
-  void Write(Mem&, Registers&, u32, u32);
+  auto Read(u32) const -> u32;
+  void Write(u32, u32);
 
   template<typename T, bool isDma>
-  void BusWrite(Mem&, u32, u32);
+  void BusWrite(u32, u32);
   template<bool isDma>
-  void BusWrite(Mem&, u32, u64);
+  void BusWrite(u32, u64);
 
   template<typename T, bool isDma>
-  auto BusRead(Mem&, u32) -> T;
+  auto BusRead(u32) -> T;
 
   bool ReadLatch();
   bool WriteLatch(u32 val);
@@ -34,5 +34,8 @@ struct PI {
   u32 piBsdDom1Pwd{}, piBsdDom2Pwd{};
   u32 piBsdDom1Pgs{}, piBsdDom2Pgs{};
   u32 piBsdDom1Rls{}, piBsdDom2Rls{};
+private:
+  Mem& mem;
+  Registers& regs;
 };
 }
\ No newline at end of file
diff --git a/src/backend/core/mmio/SI.cpp b/src/backend/core/mmio/SI.cpp
index 157e66da..db8d9a15 100644
--- a/src/backend/core/mmio/SI.cpp
+++ b/src/backend/core/mmio/SI.cpp
@@ -3,7 +3,7 @@
 #include <Scheduler.hpp>
 
 namespace n64 {
-SI::SI(Mem& mem, Registers& regs) : pif(mem, regs) {
+SI::SI(Mem& mem, Registers& regs) : mem(mem), regs(regs), pif(mem, regs) {
   Reset();
 }
 
@@ -14,7 +14,7 @@ void SI::Reset() {
   pif.Reset();
 }
 
-auto SI::Read(MI& mi, u32 addr) const -> u32 {
+auto SI::Read(u32 addr) const -> u32 {
   switch(addr) {
     case 0x04800000: return dramAddr;
     case 0x04800004: case 0x04800010: return pifAddr;
@@ -24,7 +24,7 @@ auto SI::Read(MI& mi, u32 addr) const -> u32 {
       val |= status.dmaBusy;
       val |= (0 << 1);
       val |= (0 << 3);
-      val |= (mi.miIntr.si << 12);
+      val |= (mem.mmio.mi.miIntr.si << 12);
       return val;
     }
     default:
@@ -32,26 +32,25 @@ auto SI::Read(MI& mi, u32 addr) const -> u32 {
   }
 }
 
-void SI::DMA(Mem& mem, Registers& regs) const {
-  SI& si = mem.mmio.si;
-  si.status.dmaBusy = false;
+void SI::DMA() {
+  status.dmaBusy = false;
   if (toDram) {
-    si.pif.ProcessCommands(mem);
+    pif.ProcessCommands(mem);
     for(int i = 0; i < 64; i++) {
-      mem.mmio.rdp.rdram[BYTE_ADDRESS(si.dramAddr + i)] = si.pif.Read(si.pifAddr + i);
+      mem.mmio.rdp.rdram[BYTE_ADDRESS(dramAddr + i)] = pif.Read(pifAddr + i);
     }
-    Util::trace("SI DMA from PIF RAM to RDRAM ({:08X} to {:08X})", si.pifAddr, si.dramAddr);
+    Util::trace("SI DMA from PIF RAM to RDRAM ({:08X} to {:08X})", pifAddr, dramAddr);
   } else {
     for(int i = 0; i < 64; i++) {
-      si.pif.Write(si.pifAddr + i, mem.mmio.rdp.rdram[BYTE_ADDRESS(si.dramAddr + i)]);
+      pif.Write(pifAddr + i, mem.mmio.rdp.rdram[BYTE_ADDRESS(dramAddr + i)]);
     }
-    Util::trace("SI DMA from RDRAM to PIF RAM ({:08X} to {:08X})", si.dramAddr, si.pifAddr);
-    si.pif.ProcessCommands(mem);
+    Util::trace("SI DMA from RDRAM to PIF RAM ({:08X} to {:08X})", dramAddr, pifAddr);
+    pif.ProcessCommands(mem);
   }
   mem.mmio.mi.InterruptRaise(MI::Interrupt::SI);
 }
 
-void SI::Write(Mem& mem, Registers& regs, u32 addr, u32 val) {
+void SI::Write(u32 addr, u32 val) {
   switch(addr) {
     case 0x04800000:
       dramAddr = val & RDRAM_DSIZE;
diff --git a/src/backend/core/mmio/SI.hpp b/src/backend/core/mmio/SI.hpp
index 9f1cfbd2..e58f25bb 100644
--- a/src/backend/core/mmio/SI.hpp
+++ b/src/backend/core/mmio/SI.hpp
@@ -28,10 +28,13 @@ struct SI {
   u32 pifAddr{};
   bool toDram = false;
 
-  auto Read(MI&, u32) const -> u32;
-  void Write(Mem&, Registers&, u32, u32);
-  void DMA(Mem&, Registers&) const;
+  auto Read(u32) const -> u32;
+  void Write(u32, u32);
+  void DMA();
   PIF pif;
+private:
+  Mem& mem;
+  Registers& regs;
 };
 
 #define SI_DMA_DELAY (65536 * 2)
diff --git a/src/backend/core/mmio/VI.cpp b/src/backend/core/mmio/VI.cpp
index 0995602b..f1230ac2 100644
--- a/src/backend/core/mmio/VI.cpp
+++ b/src/backend/core/mmio/VI.cpp
@@ -1,11 +1,11 @@
 #include <core/mmio/VI.hpp>
 #include <log.hpp>
 #include <core/registers/Registers.hpp>
-#include <core/mmio/MI.hpp>
+#include <core/Mem.hpp>
 #include <core/mmio/Interrupt.hpp>
 
 namespace n64 {
-VI::VI () {
+VI::VI (Mem& mem, Registers& regs) : mem(mem), regs(regs) {
   Reset();
 }
 
@@ -43,7 +43,7 @@ u32 VI::Read(u32 paddr) const {
   }
 }
 
-void VI::Write(MI& mi, Registers& regs, u32 paddr, u32 val) {
+void VI::Write(u32 paddr, u32 val) {
   switch(paddr) {
     case 0x04400000:
       status.raw = val;
@@ -63,7 +63,7 @@ void VI::Write(MI& mi, Registers& regs, u32 paddr, u32 val) {
       intr = val & 0x3FF;
     } break;
     case 0x04400010:
-      mi.InterruptLower(MI::Interrupt::VI);
+      mem.mmio.mi.InterruptLower(MI::Interrupt::VI);
       break;
     case 0x04400014: burst.raw = val; break;
     case 0x04400018: {
diff --git a/src/backend/core/mmio/VI.hpp b/src/backend/core/mmio/VI.hpp
index d7a71691..c08170a1 100644
--- a/src/backend/core/mmio/VI.hpp
+++ b/src/backend/core/mmio/VI.hpp
@@ -72,14 +72,14 @@ union AxisStart {
   };
 };
 
-struct MI;
+struct Mem;
 struct Registers;
 
 struct VI {
-  VI();
+  VI(Mem&, Registers&);
   void Reset();
   [[nodiscard]] u32 Read(u32) const;
-  void Write(MI&, Registers&, u32, u32);
+  void Write(u32, u32);
   AxisScale xscale{}, yscale{};
   VIHsyncLeap hsyncLeap{};
   VIStatus status{};
@@ -93,5 +93,8 @@ struct VI {
   int numHalflines{};
   int numFields{};
   int cyclesPerHalfline{};
+private:
+  Mem& mem;
+  Registers& regs;
 };
 } // backend
diff --git a/src/backend/core/registers/Registers.hpp b/src/backend/core/registers/Registers.hpp
index 71da4539..71e2220e 100644
--- a/src/backend/core/registers/Registers.hpp
+++ b/src/backend/core/registers/Registers.hpp
@@ -14,5 +14,16 @@ struct Registers {
   s64 hi{}, lo{};
   bool prevDelaySlot{}, delaySlot{};
   int steps = 0;
+  u32 extraCycles = 0;
+
+  void CpuStall(u32 cycles) {
+    extraCycles += cycles;
+  }
+
+  u32 PopStalledCycles() {
+    u32 ret = extraCycles;
+    extraCycles = 0;
+    return ret;
+  }
 };
 }
diff --git a/src/backend/core/rsp/instructions.cpp b/src/backend/core/rsp/instructions.cpp
index 69a06559..7f95fe85 100644
--- a/src/backend/core/rsp/instructions.cpp
+++ b/src/backend/core/rsp/instructions.cpp
@@ -75,8 +75,8 @@ FORCE_INLINE void SetCop0Reg(Registers& regs, Mem& mem, u8 index, u32 val) {
       }
       break;
     case 8: rdp.WriteStart(val); break;
-    case 9: rdp.WriteEnd(mi, regs, rsp, val); break;
-    case 11: rdp.WriteStatus(mi, regs, rsp, val); break;
+    case 9: rdp.WriteEnd(val); break;
+    case 11: rdp.WriteStatus(val); break;
     default: Util::panic("Unhandled RSP COP0 register write at index {}", index);
   }
 }