diff --git a/Source/Core/Common/BreakPoints.cpp b/Source/Core/Common/BreakPoints.cpp
index bd2355ed4b..74dcb45030 100644
--- a/Source/Core/Common/BreakPoints.cpp
+++ b/Source/Core/Common/BreakPoints.cpp
@@ -12,19 +12,19 @@
 #include "Core/PowerPC/JitCommon/JitBase.h"
 #include "Core/PowerPC/JitCommon/JitCache.h"
 
-bool BreakPoints::IsAddressBreakPoint(u32 _iAddress)
+bool BreakPoints::IsAddressBreakPoint(u32 address) const
 {
 	for (const TBreakPoint& bp : m_BreakPoints)
-		if (bp.iAddress == _iAddress)
+		if (bp.iAddress == address)
 			return true;
 
 	return false;
 }
 
-bool BreakPoints::IsTempBreakPoint(u32 _iAddress)
+bool BreakPoints::IsTempBreakPoint(u32 address) const
 {
 	for (const TBreakPoint& bp : m_BreakPoints)
-		if (bp.iAddress == _iAddress && bp.bTemporary)
+		if (bp.iAddress == address && bp.bTemporary)
 			return true;
 
 	return false;
diff --git a/Source/Core/Common/BreakPoints.h b/Source/Core/Common/BreakPoints.h
index 79b17e11ea..631284bc03 100644
--- a/Source/Core/Common/BreakPoints.h
+++ b/Source/Core/Common/BreakPoints.h
@@ -64,8 +64,8 @@ public:
 	void AddFromStrings(const TBreakPointsStr& bps);
 
 	// is address breakpoint
-	bool IsAddressBreakPoint(u32 _iAddress);
-	bool IsTempBreakPoint(u32 _iAddress);
+	bool IsAddressBreakPoint(u32 address) const;
+	bool IsTempBreakPoint(u32 address) const;
 
 	// Add BreakPoint
 	void Add(u32 em_address, bool temp = false);
diff --git a/Source/Core/Common/FileUtil.cpp b/Source/Core/Common/FileUtil.cpp
index 6779e62937..bb4ab0ca76 100644
--- a/Source/Core/Common/FileUtil.cpp
+++ b/Source/Core/Common/FileUtil.cpp
@@ -949,7 +949,7 @@ bool IOFile::Seek(s64 off, int origin)
 	return m_good;
 }
 
-u64 IOFile::Tell()
+u64 IOFile::Tell() const
 {
 	if (IsOpen())
 		return ftello(m_file);
diff --git a/Source/Core/Common/FileUtil.h b/Source/Core/Common/FileUtil.h
index 6548a95fcb..4ff158462d 100644
--- a/Source/Core/Common/FileUtil.h
+++ b/Source/Core/Common/FileUtil.h
@@ -203,10 +203,10 @@ public:
 		return WriteArray(reinterpret_cast<const char*>(data), length);
 	}
 
-	bool IsOpen() { return nullptr != m_file; }
+	bool IsOpen() const { return nullptr != m_file; }
 
 	// m_good is set to false when a read, write or other function fails
-	bool IsGood() { return m_good; }
+	bool IsGood() const { return m_good; }
 	operator void*() { return m_good ? m_file : nullptr; }
 
 	std::FILE* ReleaseHandle();
@@ -216,7 +216,7 @@ public:
 	void SetHandle(std::FILE* file);
 
 	bool Seek(s64 off, int origin);
-	u64 Tell();
+	u64 Tell() const;
 	u64 GetSize();
 	bool Resize(u64 size);
 	bool Flush();
diff --git a/Source/Core/Common/Logging/LogManager.h b/Source/Core/Common/Logging/LogManager.h
index 1d3f30df33..67f964e091 100644
--- a/Source/Core/Common/Logging/LogManager.h
+++ b/Source/Core/Common/Logging/LogManager.h
@@ -32,7 +32,7 @@ public:
 
 	void Log(LogTypes::LOG_LEVELS, const char *msg) override;
 
-	bool IsValid() { return !m_logfile.fail(); }
+	bool IsValid() const { return m_logfile.good(); }
 	bool IsEnabled() const { return m_enable; }
 	void SetEnable(bool enable) { m_enable = enable; }
 
diff --git a/Source/Core/Core/Boot/Boot_DOL.h b/Source/Core/Core/Boot/Boot_DOL.h
index 535c651c47..60f1b8d46f 100644
--- a/Source/Core/Core/Boot/Boot_DOL.h
+++ b/Source/Core/Core/Boot/Boot_DOL.h
@@ -15,8 +15,8 @@ public:
 	CDolLoader(u8* _pBuffer, u32 _Size);
 	~CDolLoader();
 
-	bool IsWii()        { return m_isWii; }
-	u32 GetEntryPoint() { return m_dolheader.entryPoint; }
+	bool IsWii()        const { return m_isWii; }
+	u32 GetEntryPoint() const { return m_dolheader.entryPoint; }
 
 	// Load into emulated memory
 	void Load();
diff --git a/Source/Core/Core/Boot/ElfReader.h b/Source/Core/Core/Boot/ElfReader.h
index d4920eb513..fa8be27890 100644
--- a/Source/Core/Core/Boot/ElfReader.h
+++ b/Source/Core/Core/Boot/ElfReader.h
@@ -69,7 +69,7 @@ public:
 	int GetSectionSize(SectionID section) const { return sections[section].sh_size; }
 	SectionID GetSectionByName(const char* name, int firstSection = 0) const; //-1 for not found
 
-	bool DidRelocate()
+	bool DidRelocate() const
 	{
 		return bRelocate;
 	}
diff --git a/Source/Core/Core/FifoPlayer/FifoDataFile.h b/Source/Core/Core/FifoPlayer/FifoDataFile.h
index 65dffc637a..b3a5e00d9f 100644
--- a/Source/Core/Core/FifoPlayer/FifoDataFile.h
+++ b/Source/Core/Core/FifoPlayer/FifoDataFile.h
@@ -67,7 +67,7 @@ public:
 
 	void AddFrame(const FifoFrameInfo &frameInfo);
 	const FifoFrameInfo &GetFrame(u32 frame) const { return m_Frames[frame]; }
-	u32 GetFrameCount() { return static_cast<u32>(m_Frames.size()); }
+	u32 GetFrameCount() const { return static_cast<u32>(m_Frames.size()); }
 
 	bool Save(const std::string& filename);
 
diff --git a/Source/Core/Core/FifoPlayer/FifoRecorder.h b/Source/Core/Core/FifoPlayer/FifoRecorder.h
index 51c37843c7..590815dd1d 100644
--- a/Source/Core/Core/FifoPlayer/FifoRecorder.h
+++ b/Source/Core/Core/FifoPlayer/FifoRecorder.h
@@ -36,7 +36,7 @@ public:
 	void SetVideoMemory(u32 *bpMem, u32 *cpMem, u32 *xfMem, u32 *xfRegs, u32 xfRegsSize);
 
 	// Checked once per frame prior to callng EndFrame()
-	bool IsRecording() { return m_IsRecording; }
+	bool IsRecording() const { return m_IsRecording; }
 
 	static FifoRecorder &GetInstance();
 
diff --git a/Source/Core/Core/GeckoCode.cpp b/Source/Core/Core/GeckoCode.cpp
index 9fd347050c..d05c1cba67 100644
--- a/Source/Core/Core/GeckoCode.cpp
+++ b/Source/Core/Core/GeckoCode.cpp
@@ -19,7 +19,7 @@ static const u32 INSTALLER_BASE_ADDRESS = 0x80001800;
 static const u32 INSTALLER_END_ADDRESS = 0x80003000;
 
 // return true if a code exists
-bool GeckoCode::Exist(u32 address, u32 data)
+bool GeckoCode::Exist(u32 address, u32 data) const
 {
 	for (const GeckoCode::Code& code : codes)
 	{
diff --git a/Source/Core/Core/GeckoCode.h b/Source/Core/Core/GeckoCode.h
index dc1947ac66..89902ef186 100644
--- a/Source/Core/Core/GeckoCode.h
+++ b/Source/Core/Core/GeckoCode.h
@@ -38,7 +38,7 @@ namespace Gecko
 		bool user_defined;
 
 		bool Compare(GeckoCode compare) const;
-		bool Exist(u32 address, u32 data);
+		bool Exist(u32 address, u32 data) const;
 	};
 
 	void SetActiveCodes(const std::vector<GeckoCode>& gcodes);
diff --git a/Source/Core/Core/HW/DSPHLE/MailHandler.cpp b/Source/Core/Core/HW/DSPHLE/MailHandler.cpp
index b2a987440d..0be2df8bbe 100644
--- a/Source/Core/Core/HW/DSPHLE/MailHandler.cpp
+++ b/Source/Core/Core/HW/DSPHLE/MailHandler.cpp
@@ -49,7 +49,7 @@ void CMailHandler::Clear()
 		m_Mails.pop();
 }
 
-bool CMailHandler::IsEmpty()
+bool CMailHandler::IsEmpty() const
 {
 	return m_Mails.empty();
 }
diff --git a/Source/Core/Core/HW/DSPHLE/MailHandler.h b/Source/Core/Core/HW/DSPHLE/MailHandler.h
index b125acdf1b..fa5b8d48af 100644
--- a/Source/Core/Core/HW/DSPHLE/MailHandler.h
+++ b/Source/Core/Core/HW/DSPHLE/MailHandler.h
@@ -19,12 +19,12 @@ public:
 	void Clear();
 	void Halt(bool _Halt);
 	void DoState(PointerWrap &p);
-	bool IsEmpty();
+	bool IsEmpty() const;
 
 	u16 ReadDSPMailboxHigh();
 	u16 ReadDSPMailboxLow();
 
-	u32 GetNextMail()
+	u32 GetNextMail() const
 	{
 		if (!m_Mails.empty())
 		{
diff --git a/Source/Core/Core/HW/EXI_Device.cpp b/Source/Core/Core/HW/EXI_Device.cpp
index c8bb9038cf..bfd5f1ba11 100644
--- a/Source/Core/Core/HW/EXI_Device.cpp
+++ b/Source/Core/Core/HW/EXI_Device.cpp
@@ -85,7 +85,7 @@ public:
 	u32  ImmRead (u32 size) override           {INFO_LOG(EXPANSIONINTERFACE, "EXI DUMMY %s ImmRead", m_strName.c_str()); return 0;}
 	void DMAWrite(u32 addr, u32 size) override {INFO_LOG(EXPANSIONINTERFACE, "EXI DUMMY %s DMAWrite: %08x bytes, from %08x to device", m_strName.c_str(), size, addr);}
 	void DMARead (u32 addr, u32 size) override {INFO_LOG(EXPANSIONINTERFACE, "EXI DUMMY %s DMARead:  %08x bytes, from device to %08x", m_strName.c_str(), size, addr);}
-	bool IsPresent() override { return true; }
+	bool IsPresent() const override { return true; }
 };
 
 
diff --git a/Source/Core/Core/HW/EXI_Device.h b/Source/Core/Core/HW/EXI_Device.h
index faea05dd42..e22aac9f90 100644
--- a/Source/Core/Core/HW/EXI_Device.h
+++ b/Source/Core/Core/HW/EXI_Device.h
@@ -39,9 +39,9 @@ public:
 	virtual void DMAWrite(u32 _uAddr, u32 _uSize);
 	virtual void DMARead (u32 _uAddr, u32 _uSize);
 
-	virtual bool UseDelayedTransferCompletion() {return false;}
+	virtual bool UseDelayedTransferCompletion() const { return false; }
 
-	virtual bool IsPresent() {return false;}
+	virtual bool IsPresent() const { return false; }
 	virtual void SetCS(int) {}
 	virtual void DoState(PointerWrap&) {}
 	virtual void PauseAndLock(bool doLock, bool unpauseOnUnlock=true) {}
diff --git a/Source/Core/Core/HW/EXI_DeviceAD16.cpp b/Source/Core/Core/HW/EXI_DeviceAD16.cpp
index 1f4e33eeab..ef26d99a30 100644
--- a/Source/Core/Core/HW/EXI_DeviceAD16.cpp
+++ b/Source/Core/Core/HW/EXI_DeviceAD16.cpp
@@ -20,7 +20,7 @@ void CEXIAD16::SetCS(int cs)
 		m_uPosition = 0;
 }
 
-bool CEXIAD16::IsPresent()
+bool CEXIAD16::IsPresent() const
 {
 	return true;
 }
diff --git a/Source/Core/Core/HW/EXI_DeviceAD16.h b/Source/Core/Core/HW/EXI_DeviceAD16.h
index d4b722db6f..e1e31c5978 100644
--- a/Source/Core/Core/HW/EXI_DeviceAD16.h
+++ b/Source/Core/Core/HW/EXI_DeviceAD16.h
@@ -11,7 +11,7 @@ class CEXIAD16 : public IEXIDevice
 public:
 	CEXIAD16();
 	virtual void SetCS(int _iCS) override;
-	virtual bool IsPresent() override;
+	virtual bool IsPresent() const override;
 	virtual void DoState(PointerWrap &p) override;
 
 private:
diff --git a/Source/Core/Core/HW/EXI_DeviceAGP.h b/Source/Core/Core/HW/EXI_DeviceAGP.h
index 6ecf30c669..3f4b6913c7 100644
--- a/Source/Core/Core/HW/EXI_DeviceAGP.h
+++ b/Source/Core/Core/HW/EXI_DeviceAGP.h
@@ -15,7 +15,7 @@ class CEXIAgp
 public:
 	CEXIAgp(const int index);
 	virtual ~CEXIAgp() override;
-	bool IsPresent() override { return true; }
+	bool IsPresent() const override { return true; }
 	void ImmWrite(u32 _uData, u32 _uSize) override;
 	u32  ImmRead(u32 _uSize) override;
 	void DoState(PointerWrap &p) override;
diff --git a/Source/Core/Core/HW/EXI_DeviceAMBaseboard.cpp b/Source/Core/Core/HW/EXI_DeviceAMBaseboard.cpp
index 477c32bd2e..c46c3b9079 100644
--- a/Source/Core/Core/HW/EXI_DeviceAMBaseboard.cpp
+++ b/Source/Core/Core/HW/EXI_DeviceAMBaseboard.cpp
@@ -21,7 +21,7 @@ void CEXIAMBaseboard::SetCS(int cs)
 		m_position = 0;
 }
 
-bool CEXIAMBaseboard::IsPresent()
+bool CEXIAMBaseboard::IsPresent() const
 {
 	return true;
 }
diff --git a/Source/Core/Core/HW/EXI_DeviceAMBaseboard.h b/Source/Core/Core/HW/EXI_DeviceAMBaseboard.h
index 59a99caa13..5ab2c7fe3b 100644
--- a/Source/Core/Core/HW/EXI_DeviceAMBaseboard.h
+++ b/Source/Core/Core/HW/EXI_DeviceAMBaseboard.h
@@ -12,7 +12,7 @@ public:
 	CEXIAMBaseboard();
 
 	virtual void SetCS(int _iCS) override;
-	virtual bool IsPresent() override;
+	virtual bool IsPresent() const override;
 	virtual bool IsInterruptSet() override;
 	virtual void DoState(PointerWrap &p) override;
 
diff --git a/Source/Core/Core/HW/EXI_DeviceEthernet.cpp b/Source/Core/Core/HW/EXI_DeviceEthernet.cpp
index 04ce72d8af..a47b4ee616 100644
--- a/Source/Core/Core/HW/EXI_DeviceEthernet.cpp
+++ b/Source/Core/Core/HW/EXI_DeviceEthernet.cpp
@@ -68,7 +68,7 @@ void CEXIETHERNET::SetCS(int cs)
 	}
 }
 
-bool CEXIETHERNET::IsPresent()
+bool CEXIETHERNET::IsPresent() const
 {
 	return true;
 }
diff --git a/Source/Core/Core/HW/EXI_DeviceEthernet.h b/Source/Core/Core/HW/EXI_DeviceEthernet.h
index 4d1f0dfb00..bd060f1434 100644
--- a/Source/Core/Core/HW/EXI_DeviceEthernet.h
+++ b/Source/Core/Core/HW/EXI_DeviceEthernet.h
@@ -193,7 +193,7 @@ public:
 	CEXIETHERNET();
 	virtual ~CEXIETHERNET();
 	void SetCS(int cs) override;
-	bool IsPresent() override;
+	bool IsPresent() const override;
 	bool IsInterruptSet() override;
 	void ImmWrite(u32 data,  u32 size) override;
 	u32  ImmRead(u32 size) override;
diff --git a/Source/Core/Core/HW/EXI_DeviceGecko.h b/Source/Core/Core/HW/EXI_DeviceGecko.h
index a0f2caea63..e78da26499 100644
--- a/Source/Core/Core/HW/EXI_DeviceGecko.h
+++ b/Source/Core/Core/HW/EXI_DeviceGecko.h
@@ -49,7 +49,7 @@ class CEXIGecko
 {
 public:
 	CEXIGecko() {}
-	bool IsPresent() override { return true; }
+	bool IsPresent() const override { return true; }
 	void ImmReadWrite(u32 &_uData, u32 _uSize) override;
 
 private:
diff --git a/Source/Core/Core/HW/EXI_DeviceIPL.cpp b/Source/Core/Core/HW/EXI_DeviceIPL.cpp
index fbb89a20b7..9a5dac25cb 100644
--- a/Source/Core/Core/HW/EXI_DeviceIPL.cpp
+++ b/Source/Core/Core/HW/EXI_DeviceIPL.cpp
@@ -160,7 +160,7 @@ void CEXIIPL::SetCS(int _iCS)
 	}
 }
 
-bool CEXIIPL::IsPresent()
+bool CEXIIPL::IsPresent() const
 {
 	return true;
 }
diff --git a/Source/Core/Core/HW/EXI_DeviceIPL.h b/Source/Core/Core/HW/EXI_DeviceIPL.h
index cb8097ea59..9e44a7b47c 100644
--- a/Source/Core/Core/HW/EXI_DeviceIPL.h
+++ b/Source/Core/Core/HW/EXI_DeviceIPL.h
@@ -16,7 +16,7 @@ public:
 	virtual ~CEXIIPL();
 
 	virtual void SetCS(int _iCS) override;
-	bool IsPresent() override;
+	bool IsPresent() const override;
 	void DoState(PointerWrap &p) override;
 
 	static u32 GetGCTime();
diff --git a/Source/Core/Core/HW/EXI_DeviceMemoryCard.cpp b/Source/Core/Core/HW/EXI_DeviceMemoryCard.cpp
index b9022556c3..a0f622a610 100644
--- a/Source/Core/Core/HW/EXI_DeviceMemoryCard.cpp
+++ b/Source/Core/Core/HW/EXI_DeviceMemoryCard.cpp
@@ -246,12 +246,12 @@ CEXIMemoryCard::~CEXIMemoryCard()
 	CoreTiming::RemoveEvent(et_transfer_complete);
 }
 
-bool CEXIMemoryCard::UseDelayedTransferCompletion()
+bool CEXIMemoryCard::UseDelayedTransferCompletion() const
 {
 	return true;
 }
 
-bool CEXIMemoryCard::IsPresent()
+bool CEXIMemoryCard::IsPresent() const
 {
 	return true;
 }
diff --git a/Source/Core/Core/HW/EXI_DeviceMemoryCard.h b/Source/Core/Core/HW/EXI_DeviceMemoryCard.h
index 7003652e30..e3d381f10a 100644
--- a/Source/Core/Core/HW/EXI_DeviceMemoryCard.h
+++ b/Source/Core/Core/HW/EXI_DeviceMemoryCard.h
@@ -14,8 +14,8 @@ public:
 	virtual ~CEXIMemoryCard();
 	void SetCS(int cs) override;
 	bool IsInterruptSet() override;
-	bool UseDelayedTransferCompletion() override;
-	bool IsPresent() override;
+	bool UseDelayedTransferCompletion() const override;
+	bool IsPresent() const override;
 	void DoState(PointerWrap &p) override;
 	IEXIDevice* FindDevice(TEXIDevices device_type, int customIndex = -1) override;
 	void DMARead(u32 _uAddr, u32 _uSize) override;
diff --git a/Source/Core/Core/HW/EXI_DeviceMic.cpp b/Source/Core/Core/HW/EXI_DeviceMic.cpp
index 540b15f488..b572957920 100644
--- a/Source/Core/Core/HW/EXI_DeviceMic.cpp
+++ b/Source/Core/Core/HW/EXI_DeviceMic.cpp
@@ -162,7 +162,7 @@ CEXIMic::~CEXIMic()
 	StreamTerminate();
 }
 
-bool CEXIMic::IsPresent()
+bool CEXIMic::IsPresent() const
 {
 	return true;
 }
diff --git a/Source/Core/Core/HW/EXI_DeviceMic.h b/Source/Core/Core/HW/EXI_DeviceMic.h
index 154016a6fe..bd2e0eba2c 100644
--- a/Source/Core/Core/HW/EXI_DeviceMic.h
+++ b/Source/Core/Core/HW/EXI_DeviceMic.h
@@ -17,7 +17,7 @@ public:
 	virtual ~CEXIMic();
 	void SetCS(int cs) override;
 	bool IsInterruptSet() override;
-	bool IsPresent() override;
+	bool IsPresent() const override;
 
 private:
 	static u8 const exi_id[];
diff --git a/Source/Core/Core/HW/GCMemcard.h b/Source/Core/Core/HW/GCMemcard.h
index 459efd937b..b44ff7e1fc 100644
--- a/Source/Core/Core/HW/GCMemcard.h
+++ b/Source/Core/Core/HW/GCMemcard.h
@@ -75,7 +75,7 @@ public:
 	virtual void ClearBlock(u32 address) = 0;
 	virtual void ClearAll() = 0;
 	virtual void DoState(PointerWrap &p) = 0;
-	u32 GetCardId() { return nintendo_card_id; }
+	u32 GetCardId() const { return nintendo_card_id; }
 	bool IsAddressInBounds(u32 address) const
 	{
 		return address <= (memory_card_size - 1);
@@ -302,11 +302,11 @@ class GCIFile
 {
 public:
 	bool LoadSaveBlocks();
-	bool HasCopyProtection()
+	bool HasCopyProtection() const
 	{
-		if ((strcmp((char *)m_gci_header.Filename, "PSO_SYSTEM") == 0) ||
-			(strcmp((char *)m_gci_header.Filename, "PSO3_SYSTEM") == 0) ||
-			(strcmp((char *)m_gci_header.Filename, "f_zero.dat") == 0))
+		if ((strcmp((char*)m_gci_header.Filename, "PSO_SYSTEM") == 0) ||
+			(strcmp((char*)m_gci_header.Filename, "PSO3_SYSTEM") == 0) ||
+			(strcmp((char*)m_gci_header.Filename, "f_zero.dat") == 0))
 			return true;
 		return false;
 	}
diff --git a/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net.cpp b/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net.cpp
index f03a44240c..f3093a3c8b 100644
--- a/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net.cpp
+++ b/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net.cpp
@@ -208,7 +208,7 @@ IPCCommandResult CWII_IPC_HLE_Device_net_kd_request::IOCtl(u32 _CommandAddress)
 }
 
 
-u8 CWII_IPC_HLE_Device_net_kd_request::GetAreaCode(const std::string& area)
+u8 CWII_IPC_HLE_Device_net_kd_request::GetAreaCode(const std::string& area) const
 {
 	static std::map<const std::string, u8> regions = {
 		{ "JPN", 0 }, { "USA", 1 }, { "EUR", 2 },
@@ -225,7 +225,7 @@ u8 CWII_IPC_HLE_Device_net_kd_request::GetAreaCode(const std::string& area)
 		return 7; // Unknown
 }
 
-u8 CWII_IPC_HLE_Device_net_kd_request::GetHardwareModel(const std::string& model)
+u8 CWII_IPC_HLE_Device_net_kd_request::GetHardwareModel(const std::string& model) const
 {
 	static std::map<const std::string, u8> models = {
 		{ "RVL", MODEL_RVL },
diff --git a/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net.h b/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net.h
index fd6b7e07f1..d2972fac5a 100644
--- a/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net.h
+++ b/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net.h
@@ -275,14 +275,14 @@ public:
 		return 0;
 	}
 
-	u32 Magic() {return Common::swap32(config.magic);}
-	void SetMagic(u32 magic) {config.magic = Common::swap32(magic);}
+	u32 Magic() const { return Common::swap32(config.magic); }
+	void SetMagic(u32 magic) { config.magic = Common::swap32(magic); }
 
-	u32 Unk() {return Common::swap32(config._unk_04);}
-	void SetUnk(u32 _unk_04) {config._unk_04 = Common::swap32(_unk_04);}
+	u32 Unk() const { return Common::swap32(config._unk_04); }
+	void SetUnk(u32 _unk_04) { config._unk_04 = Common::swap32(_unk_04); }
 
-	u32 IdGen() {return Common::swap32(config.id_generation);}
-	void SetIdGen(u32 id_generation) {config.id_generation = Common::swap32(id_generation);}
+	u32 IdGen() const { return Common::swap32(config.id_generation); }
+	void SetIdGen(u32 id_generation) { config.id_generation = Common::swap32(id_generation); }
 
 	void IncrementIdGen()
 	{
@@ -292,19 +292,19 @@ public:
 		SetIdGen(id_ctr);
 	}
 
-	u32 Checksum() {return Common::swap32(config.checksum);}
-	void SetChecksum(u32 checksum) {config.checksum = Common::swap32(checksum);}
+	u32 Checksum() const { return Common::swap32(config.checksum); }
+	void SetChecksum(u32 checksum) { config.checksum = Common::swap32(checksum); }
 
-	u32 CreationStage() {return Common::swap32(config.creation_stage);}
-	void SetCreationStage(u32 creation_stage) {config.creation_stage = Common::swap32(creation_stage);}
+	u32 CreationStage() const { return Common::swap32(config.creation_stage); }
+	void SetCreationStage(u32 creation_stage) { config.creation_stage = Common::swap32(creation_stage); }
 
-	u32 EnableBooting() {return Common::swap32(config.enable_booting);}
-	void SetEnableBooting(u32 enable_booting) {config.enable_booting = Common::swap32(enable_booting);}
+	u32 EnableBooting() const { return Common::swap32(config.enable_booting); }
+	void SetEnableBooting(u32 enable_booting) { config.enable_booting = Common::swap32(enable_booting); }
 
-	u64 Id() {return Common::swap64(config.nwc24_id);}
-	void SetId(u64 nwc24_id) {config.nwc24_id = Common::swap64(nwc24_id);}
+	u64 Id() const { return Common::swap64(config.nwc24_id); }
+	void SetId(u64 nwc24_id) { config.nwc24_id = Common::swap64(nwc24_id); }
 
-	const char* Email() {return config.email;}
+	const char* Email() const { return config.email; }
 	void SetEmail(const char* email)
 	{
 		strncpy(config.email, email, nwc24_config_t::MAX_EMAIL_LENGTH);
@@ -431,8 +431,8 @@ private:
 		MODEL_ELSE = 7
 	};
 
-	u8 GetAreaCode(const std::string& area);
-	u8 GetHardwareModel(const std::string& model);
+	u8 GetAreaCode(const std::string& area) const;
+	u8 GetHardwareModel(const std::string& model) const;
 
 	s32 NWC24MakeUserID(u64* nwc24_id, u32 hollywood_id, u16 id_ctr, u8 hardware_model, u8 area_code);
 
diff --git a/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net_ssl.cpp b/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net_ssl.cpp
index 81c3d40d74..50eac99de4 100644
--- a/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net_ssl.cpp
+++ b/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net_ssl.cpp
@@ -40,7 +40,7 @@ CWII_IPC_HLE_Device_net_ssl::~CWII_IPC_HLE_Device_net_ssl()
 	}
 }
 
-int CWII_IPC_HLE_Device_net_ssl::getSSLFreeID()
+int CWII_IPC_HLE_Device_net_ssl::GetSSLFreeID() const
 {
 	for (int i = 0; i < NET_SSL_MAXINSTANCES; i++)
 	{
@@ -134,7 +134,7 @@ IPCCommandResult CWII_IPC_HLE_Device_net_ssl::IOCtlV(u32 _CommandAddress)
 		int verifyOption = Memory::Read_U32(BufferOut);
 		std::string hostname = Memory::GetString(BufferOut2, BufferOutSize2);
 
-		int freeSSL = this->getSSLFreeID();
+		int freeSSL = GetSSLFreeID();
 		if (freeSSL)
 		{
 			int sslID = freeSSL - 1;
diff --git a/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net_ssl.h b/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net_ssl.h
index 3cf12810b9..acce2a47a4 100644
--- a/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net_ssl.h
+++ b/Source/Core/Core/IPC_HLE/WII_IPC_HLE_Device_net_ssl.h
@@ -81,7 +81,7 @@ public:
 	virtual IPCCommandResult IOCtl(u32 _CommandAddress) override;
 	virtual IPCCommandResult IOCtlV(u32 _CommandAddress) override;
 
-	int getSSLFreeID();
+	int GetSSLFreeID() const;
 
 	static WII_SSL _SSL[NET_SSL_MAXINSTANCES];
 };
diff --git a/Source/Core/Core/IPC_HLE/WII_IPC_HLE_WiiMote.h b/Source/Core/Core/IPC_HLE/WII_IPC_HLE_WiiMote.h
index fd8a98accc..e03951bbbd 100644
--- a/Source/Core/Core/IPC_HLE/WII_IPC_HLE_WiiMote.h
+++ b/Source/Core/Core/IPC_HLE/WII_IPC_HLE_WiiMote.h
@@ -21,9 +21,9 @@ class CBigEndianBuffer
 public:
 	CBigEndianBuffer(u8* pBuffer) : m_pBuffer(pBuffer) {}
 
-	u8   Read8(u32 offset)              { return m_pBuffer[offset]; }
-	u16  Read16(u32 offset)             { return Common::swap16(*(u16*)&m_pBuffer[offset]); }
-	u32  Read32(u32 offset)             { return Common::swap32(*(u32*)&m_pBuffer[offset]); }
+	u8   Read8(u32 offset)  const       { return m_pBuffer[offset]; }
+	u16  Read16(u32 offset) const       { return Common::swap16(*(u16*)&m_pBuffer[offset]); }
+	u32  Read32(u32 offset) const       { return Common::swap32(*(u32*)&m_pBuffer[offset]); }
 
 	void Write8(u32 offset, u8 data)    { m_pBuffer[offset] = data; }
 	void Write16(u32 offset, u16 data)  { *(u16*)&m_pBuffer[offset] = Common::swap16(data); }
diff --git a/Source/Core/Core/IPC_HLE/WII_Socket.h b/Source/Core/Core/IPC_HLE/WII_Socket.h
index 2f1c93a3dc..4956c4dd24 100644
--- a/Source/Core/Core/IPC_HLE/WII_Socket.h
+++ b/Source/Core/Core/IPC_HLE/WII_Socket.h
@@ -189,7 +189,7 @@ private:
 	void DoSock(u32 _CommandAddress, NET_IOCTL type);
 	void DoSock(u32 _CommandAddress, SSL_IOCTL type);
 	void Update(bool read, bool write, bool except);
-	bool IsValid() { return fd >= 0; }
+	bool IsValid() const { return fd >= 0; }
 public:
 	WiiSocket() : fd(-1), nonBlock(false) {}
 	~WiiSocket();
@@ -216,7 +216,7 @@ public:
 	s32 NewSocket(s32 af, s32 type, s32 protocol);
 	void AddSocket(s32 fd);
 	s32 DeleteSocket(s32 s);
-	s32 GetLastNetError() { return errno_last; }
+	s32 GetLastNetError() const { return errno_last; }
 	void SetLastNetError(s32 error) { errno_last = error; }
 
 	void Clean()
diff --git a/Source/Core/VideoBackends/D3D/D3DBlob.cpp b/Source/Core/VideoBackends/D3D/D3DBlob.cpp
index a4ed6c4683..5f70ceb4b8 100644
--- a/Source/Core/VideoBackends/D3D/D3DBlob.cpp
+++ b/Source/Core/VideoBackends/D3D/D3DBlob.cpp
@@ -44,7 +44,7 @@ unsigned int D3DBlob::Release()
 	return ref;
 }
 
-unsigned int D3DBlob::Size()
+unsigned int D3DBlob::Size() const
 {
 	return size;
 }
diff --git a/Source/Core/VideoBackends/D3D/D3DBlob.h b/Source/Core/VideoBackends/D3D/D3DBlob.h
index 5f228147d2..bacf98d983 100644
--- a/Source/Core/VideoBackends/D3D/D3DBlob.h
+++ b/Source/Core/VideoBackends/D3D/D3DBlob.h
@@ -24,7 +24,7 @@ public:
 	void AddRef();
 	unsigned int Release();
 
-	unsigned int Size();
+	unsigned int Size() const;
 	u8* Data();
 
 private:
diff --git a/Source/Core/VideoCommon/TextureCacheBase.h b/Source/Core/VideoCommon/TextureCacheBase.h
index b76883173b..0006ff9266 100644
--- a/Source/Core/VideoCommon/TextureCacheBase.h
+++ b/Source/Core/VideoCommon/TextureCacheBase.h
@@ -95,7 +95,7 @@ public:
 
 		bool OverlapsMemoryRange(u32 range_address, u32 range_size) const;
 
-		bool IsEfbCopy() { return is_efb_copy; }
+		bool IsEfbCopy() const { return is_efb_copy; }
 	};
 
 	virtual ~TextureCache(); // needs virtual for DX11 dtor