diff --git a/Source/Core/Core/HW/DVD/DVDInterface.cpp b/Source/Core/Core/HW/DVD/DVDInterface.cpp
diff --git a/Source/Core/Core/HW/DVD/DVDInterface.h b/Source/Core/Core/HW/DVD/DVDInterface.h
@@ -51,33 +51,41 @@ enum class DICommand : u8
   UnknownEE = 0xee,
 };
 
-// "low" error codes
-constexpr u32 ERROR_READY = 0x0000000;          // Ready.
-constexpr u32 ERROR_COVER = 0x01000000;         // Cover is opened.
-constexpr u32 ERROR_CHANGE_DISK = 0x02000000;   // Disk change.
-constexpr u32 ERROR_NO_DISK_L = 0x03000000;     // No disk.
-constexpr u32 ERROR_MOTOR_STOP_L = 0x04000000;  // Motor stop.
-constexpr u32 ERROR_NO_DISKID_L = 0x05000000;   // Disk ID not read.
-constexpr u32 LOW_ERROR_MASK = 0xff000000;
-
-// "high" error codes
-constexpr u32 ERROR_NONE = 0x000000;          // No error.
-constexpr u32 ERROR_MOTOR_STOP_H = 0x020400;  // Motor stopped.
-constexpr u32 ERROR_NO_DISKID_H = 0x020401;   // Disk ID not read.
-constexpr u32 ERROR_NO_DISK_H = 0x023a00;     // Medium not present / Cover opened.
-constexpr u32 ERROR_SEEK_NDONE = 0x030200;    // No seek complete.
-constexpr u32 ERROR_READ = 0x031100;          // Unrecovered read error.
-constexpr u32 ERROR_PROTOCOL = 0x040800;      // Transfer protocol error.
-constexpr u32 ERROR_INV_CMD = 0x052000;       // Invalid command operation code.
-constexpr u32 ERROR_AUDIO_BUF = 0x052001;     // Audio Buffer not set.
-constexpr u32 ERROR_BLOCK_OOB = 0x052100;     // Logical block address out of bounds.
-constexpr u32 ERROR_INV_FIELD = 0x052400;     // Invalid field in command packet.
-constexpr u32 ERROR_INV_AUDIO = 0x052401;     // Invalid audio command.
-constexpr u32 ERROR_INV_PERIOD = 0x052402;    // Configuration out of permitted period.
-constexpr u32 ERROR_END_USR_AREA = 0x056300;  // End of user area encountered on this track.
-constexpr u32 ERROR_MEDIUM = 0x062800;        // Medium may have changed.
-constexpr u32 ERROR_MEDIUM_REQ = 0x0b5a01;    // Operator medium removal request.
-constexpr u32 HIGH_ERROR_MASK = 0x00ffffff;
+// Disc drive state.
+// Reported in error codes as 0 for Ready, and value-1 for the rest
+// (i.e. Ready and ReadyNoReadsMade are both reported as 0)
+enum class DriveState : u8
+{
+  Ready = 0,
+  ReadyNoReadsMade = 1,
+  CoverOpened = 2,
+  DiscChangeDetected = 3,
+  NoMediumPresent = 4,
+  MotorStopped = 5,
+  DiscIdNotRead = 6
+};
+
+// Actual drive error codes, which fill the remaining 3 bytes
+// Numbers more or less match a SCSI sense key (1 nybble) followed by SCSI ASC/ASCQ (2 bytes).
+enum class DriveError : u32
+{
+  None = 0x00000,                  // No error.
+  MotorStopped = 0x20400,          // Motor stopped.
+  NoDiscID = 0x20401,              // Disk ID not read.
+  MediumNotPresent = 0x23a00,      // Medium not present / Cover opened.
+  SeekNotDone = 0x30200,           // No seek complete.
+  ReadError = 0x31100,             // Unrecovered read error.
+  ProtocolError = 0x40800,         // Transfer protocol error.
+  InvalidCommand = 0x52000,        // Invalid command operation code.
+  NoAudioBuf = 0x52001,            // Audio Buffer not set.
+  BlockOOB = 0x52100,              // Logical block address out of bounds.
+  InvalidField = 0x52400,          // Invalid field in command packet.
+  InvalidAudioCommand = 0x52401,   // Invalid audio command.
+  InvalidPeriod = 0x52402,         // Configuration out of permitted period.
+  EndOfUserArea = 0x56300,         // End of user area encountered on this track.
+  MediumChanged = 0x62800,         // Medium may have changed.
+  MediumRemovalRequest = 0xb5a01,  // Operator medium removal request.
+};
 
 enum class DIInterruptType : int
 {
@@ -102,7 +110,7 @@ enum class EjectCause
 };
 
 void Init();
-void Reset(bool spinup = true);
+void ResetDrive(bool spinup);
 void Shutdown();
 void DoState(PointerWrap& p);
 
@@ -130,8 +138,8 @@ void PerformDecryptingRead(u32 position, u32 length, u32 output_address,
 // Exposed for use by emulated BS2; does not perform any checks on drive state
 void AudioBufferConfig(bool enable_dtk, u8 dtk_buffer_length);
 
-void SetLowError(u32 low_error);
-void SetHighError(u32 high_error);
+void SetDriveState(DriveState state);
+void SetDriveError(DriveError error);
 
 // Used by DVDThread
 void FinishExecutingCommand(ReplyType reply_type, DIInterruptType interrupt_type, s64 cycles_late,

diff --git a/Source/Core/Core/HW/DVD/DVDThread.cpp b/Source/Core/Core/HW/DVD/DVDThread.cpp
@@ -348,7 +348,7 @@ static void FinishRead(u64 id, s64 cycles_late)
     PanicAlertT("The disc could not be read (at 0x%" PRIx64 " - 0x%" PRIx64 ").",
                 request.dvd_offset, request.dvd_offset + request.length);
 
-    DVDInterface::SetHighError(DVDInterface::ERROR_BLOCK_OOB);
+    DVDInterface::SetDriveError(DVDInterface::DriveError::BlockOOB);
     interrupt = DVDInterface::DIInterruptType::DEINT;
   }
   else

diff --git a/Source/Core/Core/HW/ProcessorInterface.cpp b/Source/Core/Core/HW/ProcessorInterface.cpp
@@ -11,6 +11,7 @@
 #include "Common/CommonTypes.h"
 #include "Core/Core.h"
 #include "Core/CoreTiming.h"
+#include "Core/HW/DVD/DVDInterface.h"
 #include "Core/HW/MMIO.h"
 #include "Core/HW/SystemTimers.h"
 #include "Core/IOS/IOS.h"
@@ -111,8 +112,18 @@ void RegisterMMIO(MMIO::Mapping* mmio, u32 base)
                  MMIO::ComplexWrite<u32>(
                      [](u32, u32 val) { WARN_LOG(PROCESSORINTERFACE, "Fifo reset (%08x)", val); }));
 
-  mmio->Register(base | PI_RESET_CODE, MMIO::DirectRead<u32>(&m_ResetCode),
-                 MMIO::DirectWrite<u32>(&m_ResetCode));
+  mmio->Register(base | PI_RESET_CODE, MMIO::ComplexRead<u32>([](u32) {
+                   DEBUG_LOG(PROCESSORINTERFACE, "Read PI_RESET_CODE: %08x", m_ResetCode);
+                   return m_ResetCode;
+                 }),
+                 MMIO::ComplexWrite<u32>([](u32, u32 val) {
+                   m_ResetCode = val;
+                   INFO_LOG(PROCESSORINTERFACE, "Wrote PI_RESET_CODE: %08x", m_ResetCode);
+                   if (~m_ResetCode & 0x4)
+                   {
+                     DVDInterface::ResetDrive(true);
+                   }
+                 }));
 
   mmio->Register(base | PI_FLIPPER_REV, MMIO::DirectRead<u32>(&m_FlipperRev),
                  MMIO::InvalidWrite<u32>());

diff --git a/Source/Core/Core/IOS/DI/DI.cpp b/Source/Core/Core/IOS/DI/DI.cpp
@@ -266,9 +266,9 @@ std::optional<DI::DIResult> DI::StartIOCtl(const IOCtlRequest& request)
     return DIResult::Success;
   case DIIoctl::DVDLowReset:
   {
-    const bool spinup = Memory::Read_U32(request.address + 4);
+    const bool spinup = Memory::Read_U32(request.buffer_in + 4);
     INFO_LOG(IOS_DI, "DVDLowReset %s spinup", spinup ? "with" : "without");
-    DVDInterface::Reset(spinup);
+    DVDInterface::ResetDrive(spinup);
     ResetDIRegisters();
     return DIResult::Success;
   }

diff --git a/Source/Core/Core/IOS/MIOS.cpp b/Source/Core/Core/IOS/MIOS.cpp
@@ -37,7 +37,7 @@ static void ReinitHardware()
   // HACK However, resetting DI will reset the DTK config, which is set by the system menu
   // (and not by MIOS), causing games that use DTK to break.  Perhaps MIOS doesn't actually
   // reset DI fully, in such a way that the DTK config isn't cleared?
-  // DVDInterface::Reset();
+  // DVDInterface::ResetDrive(true);
   PowerPC::Reset();
   Wiimote::ResetAllWiimotes();
   // Note: this is specific to Dolphin and is required because we initialised it in Wii mode.

diff --git a/Source/Core/Core/State.cpp b/Source/Core/Core/State.cpp
@@ -74,7 +74,7 @@ static Common::Event g_compressAndDumpStateSyncEvent;
 static std::thread g_save_thread;
 
 // Don't forget to increase this after doing changes on the savestate system
-constexpr u32 STATE_VERSION = 121;  // Last changed in PR 8988
+constexpr u32 STATE_VERSION = 122;  // Last changed in PR 8571
 
 // Maps savestate versions to Dolphin versions.
 // Versions after 42 don't need to be added to this list,