Remove the last `ConfigEntry` state (#1902)

* Get rid of `ConfigEntry::ExternalBIOSEnable`

- Now the BIOS files themselves are checked
- The frontend's `Config::ExternalBIOSEnable` is not affected

* Add `JITArgs`

* Pass the JIT status to the `ARM` constructors

* Encapsulate `NDS::EnableJIT`

* Pass `JITArgs` to `ARMJIT`'s constructor

* Remove the `JIT_*` `ConfigEntry`s in favor of members

- Allow all the JIT args to be set with `NDS::SetJITArgs`
- Encapsulate the JIT-related parameters in `ARMJIT` so they can reset the block cache if changed
- Update the active (or newly-created) console in the frontend with adjusted JIT args

* Make audio bit depth and interpolation configurable in `NDSArgs`

- Define enums for both
- Give those settings default values in `NDSArgs`
- Remove `ConfigEntry::AudioBitDepth`
- Initialize these settings in the relevant SPU constructors

* Move the last DSi-specific logic in `Reset` to its own subclass

* Remove `ConfigEntry::DSi_FullBIOSBoot`

- Add members to `DSi` instead for getting and setting this
- Update the frontend to accommodate these changes

* Oops, missed a spot

* Remove `ConfigEntry::Firm_MAC` and `Platform::GetConfigArray`

- Also move the MAC parsing code to `ROMManager`

* Remove the last `ConfigEntry` state

- Make GDB support configurable via members

* Add some `#ifdef`s that I'd almost forgotten

20 files changed, 323 insertions, 230 deletions

diff --git a/src/ARM.cpp b/src/ARM.cpp
index 659d303..2c19fa3 100644
--- a/src/ARM.cpp
+++ b/src/ARM.cpp
@@ -106,17 +106,17 @@ const u32 ARM::ConditionTable[16] =
     0x0000  // NE
 };
 
-ARM::ARM(u32 num, melonDS::NDS& nds) :
+ARM::ARM(u32 num, bool jit, std::optional<GDBArgs> gdb, melonDS::NDS& nds) :
 #ifdef GDBSTUB_ENABLED
-    GdbStub(this, Platform::GetConfigInt(num ? Platform::GdbPortARM7 : Platform::GdbPortARM9)),
+    GdbStub(this, gdb ? (num ? gdb->PortARM7 : gdb->PortARM9) : 0),
 #endif
     Num(num), // well uh
     NDS(nds)
 {
 #ifdef GDBSTUB_ENABLED
-    if (Platform::GetConfigBool(Platform::GdbEnabled)
+    if (gdb
 #ifdef JIT_ENABLED
-            && !Platform::GetConfigBool(Platform::JIT_Enable)
+            && !jit // TODO: Should we support toggling the GdbStub without destroying the ARM?
 #endif
     )
         GdbStub.Init();
@@ -129,14 +129,14 @@ ARM::~ARM()
     // dorp
 }
 
-ARMv5::ARMv5(melonDS::NDS& nds) : ARM(0, nds)
+ARMv5::ARMv5(melonDS::NDS& nds, std::optional<GDBArgs> gdb, bool jit) : ARM(0, jit, gdb, nds)
 {
     DTCM = NDS.JIT.Memory.GetARM9DTCM();
 
     PU_Map = PU_PrivMap;
 }
 
-ARMv4::ARMv4(melonDS::NDS& nds) : ARM(1, nds)
+ARMv4::ARMv4(melonDS::NDS& nds, std::optional<GDBArgs> gdb, bool jit) : ARM(1, jit, gdb, nds)
 {
     //
 }
@@ -187,8 +187,6 @@ void ARM::Reset()
 #ifdef GDBSTUB_ENABLED
     IsSingleStep = false;
     BreakReq = false;
-    BreakOnStartup = Platform::GetConfigBool(
-        Num ? Platform::GdbARM7BreakOnStartup : Platform::GdbARM9BreakOnStartup);
 #endif
 
     // zorp
@@ -224,7 +222,7 @@ void ARM::DoSavestate(Savestate* file)
     file->VarArray(R_UND, 3*sizeof(u32));
     file->Var32(&CurInstr);
 #ifdef JIT_ENABLED
-    if (file->Saving && NDS.EnableJIT)
+    if (file->Saving && NDS.IsJITEnabled())
     {
         // hack, the JIT doesn't really pipeline
         // but we still want JIT save states to be
diff --git a/src/ARM.h b/src/ARM.h
index 4becff0..65f78ab 100644
--- a/src/ARM.h
+++ b/src/ARM.h
@@ -20,6 +20,7 @@
 #define ARM_H
 
 #include <algorithm>
+#include <optional>
 
 #include "types.h"
 #include "MemRegion.h"
@@ -44,7 +45,7 @@ enum
 const u32 ITCMPhysicalSize = 0x8000;
 const u32 DTCMPhysicalSize = 0x4000;
 
-
+struct GDBArgs;
 class ARMJIT;
 class GPU;
 class ARMJIT_Memory;
@@ -57,7 +58,7 @@ class ARM
 #endif
 {
 public:
-    ARM(u32 num, NDS& nds);
+    ARM(u32 num, bool jit, std::optional<GDBArgs> gdb, NDS& nds);
     virtual ~ARM(); // destroy shit
 
     virtual void Reset();
@@ -202,6 +203,7 @@ protected:
     bool IsSingleStep;
     bool BreakReq;
     bool BreakOnStartup;
+    u16 Port;
 
 public:
     int GetCPU() const override { return Num ? 7 : 9; }
@@ -225,7 +227,7 @@ protected:
 class ARMv5 : public ARM
 {
 public:
-    ARMv5(melonDS::NDS& nds);
+    ARMv5(melonDS::NDS& nds, std::optional<GDBArgs> gdb, bool jit);
     ~ARMv5();
 
     void Reset() override;
@@ -377,7 +379,7 @@ protected:
 class ARMv4 : public ARM
 {
 public:
-    ARMv4(melonDS::NDS& nds);
+    ARMv4(melonDS::NDS& nds, std::optional<GDBArgs> gdb, bool jit);
 
     void FillPipeline() override;
 
diff --git a/src/ARMJIT.cpp b/src/ARMJIT.cpp
index b938dfb..5e0e207 100644
--- a/src/ARMJIT.cpp
+++ b/src/ARMJIT.cpp
@@ -237,16 +237,6 @@ ARMJIT::~ARMJIT() noexcept
 
 void ARMJIT::Reset() noexcept
 {
-    MaxBlockSize = Platform::GetConfigInt(Platform::JIT_MaxBlockSize);
-    LiteralOptimizations = Platform::GetConfigBool(Platform::JIT_LiteralOptimizations);
-    BranchOptimizations = Platform::GetConfigBool(Platform::JIT_BranchOptimizations);
-    FastMemory = Platform::GetConfigBool(Platform::JIT_FastMemory);
-
-    if (MaxBlockSize < 1)
-        MaxBlockSize = 1;
-    if (MaxBlockSize > 32)
-        MaxBlockSize = 32;
-
     JitEnableWrite();
     ResetBlockCache();
 
@@ -491,6 +481,56 @@ void ARMJIT::RetireJitBlock(JitBlock* block) noexcept
     }
 }
 
+void ARMJIT::SetJITArgs(JITArgs args) noexcept
+{
+    args.MaxBlockSize = std::clamp(args.MaxBlockSize, 1u, 32u);
+
+    if (MaxBlockSize != args.MaxBlockSize
+        || LiteralOptimizations != args.LiteralOptimizations
+        || BranchOptimizations != args.BranchOptimizations
+        || FastMemory != args.FastMemory)
+        ResetBlockCache();
+
+    MaxBlockSize = args.MaxBlockSize;
+    LiteralOptimizations = args.LiteralOptimizations;
+    BranchOptimizations = args.BranchOptimizations;
+    FastMemory = args.FastMemory;
+}
+
+void ARMJIT::SetMaxBlockSize(int size) noexcept
+{
+    size = std::clamp(size, 1, 32);
+
+    if (size != MaxBlockSize)
+        ResetBlockCache();
+
+    MaxBlockSize = size;
+}
+
+void ARMJIT::SetLiteralOptimizations(bool enabled) noexcept
+{
+    if (LiteralOptimizations != enabled)
+        ResetBlockCache();
+
+    LiteralOptimizations = enabled;
+}
+
+void ARMJIT::SetBranchOptimizations(bool enabled) noexcept
+{
+    if (BranchOptimizations != enabled)
+        ResetBlockCache();
+
+    BranchOptimizations = enabled;
+}
+
+void ARMJIT::SetFastMemory(bool enabled) noexcept
+{
+    if (FastMemory != enabled)
+        ResetBlockCache();
+
+    FastMemory = enabled;
+}
+
 void ARMJIT::CompileBlock(ARM* cpu) noexcept
 {
     bool thumb = cpu->CPSR & 0x20;
diff --git a/src/ARMJIT.h b/src/ARMJIT.h
index 9e1ca07..6390855 100644
--- a/src/ARMJIT.h
+++ b/src/ARMJIT.h
@@ -19,6 +19,8 @@
 #ifndef ARMJIT_H
 #define ARMJIT_H
 
+#include <algorithm>
+#include <optional>
 #include <memory>
 #include "types.h"
 
@@ -30,6 +32,7 @@
 #endif
 
 #include "ARMJIT_Compiler.h"
+#include "Args.h"
 #include "MemConstants.h"
 
 namespace melonDS
@@ -40,7 +43,15 @@ class JitBlock;
 class ARMJIT
 {
 public:
-    ARMJIT(melonDS::NDS& nds) noexcept : NDS(nds), Memory(nds), JITCompiler(nds) {};
+    ARMJIT(melonDS::NDS& nds, std::optional<JITArgs> jit) noexcept :
+        NDS(nds),
+        Memory(nds),
+        JITCompiler(nds),
+        MaxBlockSize(jit.has_value() ? std::clamp(jit->MaxBlockSize, 1u, 32u) : 32),
+        LiteralOptimizations(jit.has_value() ? jit->LiteralOptimizations : false),
+        BranchOptimizations(jit.has_value() ? jit->BranchOptimizations : false),
+        FastMemory(jit.has_value() ? jit->FastMemory : false)
+    {}
     ~ARMJIT() noexcept NOOP_IF_NO_JIT;
     void InvalidateByAddr(u32) noexcept NOOP_IF_NO_JIT;
     void CheckAndInvalidateWVRAM(int) noexcept NOOP_IF_NO_JIT;
@@ -68,17 +79,29 @@ public:
 #endif
 
     ARMJIT_Memory Memory;
+private:
     int MaxBlockSize {};
     bool LiteralOptimizations = false;
     bool BranchOptimizations = false;
     bool FastMemory = false;
-
+public:
     melonDS::NDS& NDS;
     TinyVector<u32> InvalidLiterals {};
     friend class ARMJIT_Memory;
     void blockSanityCheck(u32 num, u32 blockAddr, JitBlockEntry entry) noexcept;
     void RetireJitBlock(JitBlock* block) noexcept;
 
+    int GetMaxBlockSize() const noexcept { return MaxBlockSize; }
+    bool LiteralOptimizationsEnabled() const noexcept { return LiteralOptimizations; }
+    bool BranchOptimizationsEnabled() const noexcept { return BranchOptimizations; }
+    bool FastMemoryEnabled() const noexcept { return FastMemory; }
+
+    void SetJITArgs(JITArgs args) noexcept;
+    void SetMaxBlockSize(int size) noexcept;
+    void SetLiteralOptimizations(bool enabled) noexcept;
+    void SetBranchOptimizations(bool enabled) noexcept;
+    void SetFastMemory(bool enabled) noexcept;
+
     Compiler JITCompiler;
     std::unordered_map<u32, JitBlock*> JitBlocks9 {};
     std::unordered_map<u32, JitBlock*> JitBlocks7 {};
diff --git a/src/ARMJIT_A64/ARMJIT_LoadStore.cpp b/src/ARMJIT_A64/ARMJIT_LoadStore.cpp
index 22a410a..4007138 100644
--- a/src/ARMJIT_A64/ARMJIT_LoadStore.cpp
+++ b/src/ARMJIT_A64/ARMJIT_LoadStore.cpp
@@ -112,7 +112,7 @@ void Compiler::Comp_MemAccess(int rd, int rn, Op2 offset, int size, int flags)
     if (size == 16)
         addressMask = ~1;
 
-    if (NDS.JIT.LiteralOptimizations && rn == 15 && rd != 15 && offset.IsImm && !(flags & (memop_Post|memop_Store|memop_Writeback)))
+    if (NDS.JIT.LiteralOptimizationsEnabled() && rn == 15 && rd != 15 && offset.IsImm && !(flags & (memop_Post|memop_Store|memop_Writeback)))
     {
         u32 addr = R15 + offset.Imm * ((flags & memop_SubtractOffset) ? -1 : 1);
         
@@ -147,7 +147,7 @@ void Compiler::Comp_MemAccess(int rd, int rn, Op2 offset, int size, int flags)
         MOV(W0, rnMapped);
     }
 
-    bool addrIsStatic = NDS.JIT.LiteralOptimizations
+    bool addrIsStatic = NDS.JIT.LiteralOptimizationsEnabled()
         && RegCache.IsLiteral(rn) && offset.IsImm && !(flags & (memop_Writeback|memop_Post));
     u32 staticAddress;
     if (addrIsStatic)
@@ -189,7 +189,7 @@ void Compiler::Comp_MemAccess(int rd, int rn, Op2 offset, int size, int flags)
         ? NDS.JIT.Memory.ClassifyAddress9(addrIsStatic ? staticAddress : CurInstr.DataRegion)
         : NDS.JIT.Memory.ClassifyAddress7(addrIsStatic ? staticAddress : CurInstr.DataRegion);
 
-    if (NDS.JIT.FastMemory && ((!Thumb && CurInstr.Cond() != 0xE) || NDS.JIT.Memory.IsFastmemCompatible(expectedTarget)))
+    if (NDS.JIT.FastMemoryEnabled() && ((!Thumb && CurInstr.Cond() != 0xE) || NDS.JIT.Memory.IsFastmemCompatible(expectedTarget)))
     {
         ptrdiff_t memopStart = GetCodeOffset();
         LoadStorePatch patch;
@@ -453,7 +453,7 @@ void Compiler::T_Comp_LoadPCRel()
     u32 offset = ((CurInstr.Instr & 0xFF) << 2);
     u32 addr = (R15 & ~0x2) + offset;
 
-    if (!NDS.JIT.LiteralOptimizations || !Comp_MemLoadLiteral(32, false, CurInstr.T_Reg(8), addr))
+    if (!NDS.JIT.LiteralOptimizationsEnabled() || !Comp_MemLoadLiteral(32, false, CurInstr.T_Reg(8), addr))
         Comp_MemAccess(CurInstr.T_Reg(8), 15, Op2(offset), 32, 0);
 }
 
@@ -498,7 +498,7 @@ s32 Compiler::Comp_MemAccessBlock(int rn, BitSet16 regs, bool store, bool preinc
         ? NDS.JIT.Memory.ClassifyAddress9(CurInstr.DataRegion)
         : NDS.JIT.Memory.ClassifyAddress7(CurInstr.DataRegion);
 
-    bool compileFastPath = NDS.JIT.FastMemory
+    bool compileFastPath = NDS.JIT.FastMemoryEnabled()
         && store && !usermode && (CurInstr.Cond() < 0xE || NDS.JIT.Memory.IsFastmemCompatible(expectedTarget));
 
     {
diff --git a/src/ARMJIT_x64/ARMJIT_LoadStore.cpp b/src/ARMJIT_x64/ARMJIT_LoadStore.cpp
index 72a073d..8520beb 100644
--- a/src/ARMJIT_x64/ARMJIT_LoadStore.cpp
+++ b/src/ARMJIT_x64/ARMJIT_LoadStore.cpp
@@ -119,7 +119,7 @@ void Compiler::Comp_MemAccess(int rd, int rn, const Op2& op2, int size, int flag
     if (size == 16)
         addressMask = ~1;
 
-    if (NDS.JIT.LiteralOptimizations && rn == 15 && rd != 15 && op2.IsImm && !(flags & (memop_Post|memop_Store|memop_Writeback)))
+    if (NDS.JIT.LiteralOptimizationsEnabled() && rn == 15 && rd != 15 && op2.IsImm && !(flags & (memop_Post|memop_Store|memop_Writeback)))
     {
         u32 addr = R15 + op2.Imm * ((flags & memop_SubtractOffset) ? -1 : 1);
 
@@ -136,7 +136,7 @@ void Compiler::Comp_MemAccess(int rd, int rn, const Op2& op2, int size, int flag
         Comp_AddCycles_CDI();
     }
 
-    bool addrIsStatic = NDS.JIT.LiteralOptimizations
+    bool addrIsStatic = NDS.JIT.LiteralOptimizationsEnabled()
         && RegCache.IsLiteral(rn) && op2.IsImm && !(flags & (memop_Writeback|memop_Post));
     u32 staticAddress;
     if (addrIsStatic)
@@ -200,7 +200,7 @@ void Compiler::Comp_MemAccess(int rd, int rn, const Op2& op2, int size, int flag
         ? NDS.JIT.Memory.ClassifyAddress9(CurInstr.DataRegion)
         : NDS.JIT.Memory.ClassifyAddress7(CurInstr.DataRegion);
 
-    if (NDS.JIT.FastMemory && ((!Thumb && CurInstr.Cond() != 0xE) || NDS.JIT.Memory.IsFastmemCompatible(expectedTarget)))
+    if (NDS.JIT.FastMemoryEnabled() && ((!Thumb && CurInstr.Cond() != 0xE) || NDS.JIT.Memory.IsFastmemCompatible(expectedTarget)))
     {
         if (rdMapped.IsImm())
         {
@@ -431,7 +431,7 @@ s32 Compiler::Comp_MemAccessBlock(int rn, BitSet16 regs, bool store, bool preinc
     else
         Comp_AddCycles_CD();
 
-    bool compileFastPath = NDS.JIT.FastMemory
+    bool compileFastPath = NDS.JIT.FastMemoryEnabled()
         && !usermode && (CurInstr.Cond() < 0xE || NDS.JIT.Memory.IsFastmemCompatible(expectedTarget));
 
     // we need to make sure that the stack stays aligned to 16 bytes
@@ -809,7 +809,7 @@ void Compiler::T_Comp_LoadPCRel()
 {
     u32 offset = (CurInstr.Instr & 0xFF) << 2;
     u32 addr = (R15 & ~0x2) + offset;
-    if (!NDS.JIT.LiteralOptimizations || !Comp_MemLoadLiteral(32, false, CurInstr.T_Reg(8), addr))
+    if (!NDS.JIT.LiteralOptimizationsEnabled() || !Comp_MemLoadLiteral(32, false, CurInstr.T_Reg(8), addr))
         Comp_MemAccess(CurInstr.T_Reg(8), 15, Op2(offset), 32, 0);
 }
 
diff --git a/src/Args.h b/src/Args.h
index bfa1b13..c6d131c 100644
--- a/src/Args.h
+++ b/src/Args.h
@@ -23,12 +23,15 @@
 #include <optional>
 #include <memory>
 
+#include "NDSCart.h"
+#include "GBACart.h"
 #include "types.h"
 #include "MemConstants.h"
 #include "DSi_NAND.h"
 #include "FATStorage.h"
 #include "FreeBIOS.h"
 #include "SPI_Firmware.h"
+#include "SPU.h"
 
 namespace melonDS
 {
@@ -50,6 +53,29 @@ constexpr std::array<u8, N> BrokenBIOS = []() constexpr {
     return broken;
 }();
 
+/// Arguments that configure the JIT.
+/// Ignored in builds that don't have the JIT included.
+struct JITArgs
+{
+    unsigned MaxBlockSize = 32;
+    bool LiteralOptimizations = true;
+    bool BranchOptimizations = true;
+
+    /// Ignored in builds that have fast memory excluded
+    /// (even if the JIT is otherwise available).
+    /// Enabled by default, but frontends should disable this when debugging
+    /// so the constants segfaults don't hinder debugging.
+    bool FastMemory = true;
+};
+
+struct GDBArgs
+{
+    u16 PortARM7 = 0;
+    u16 PortARM9 = 0;
+    bool ARM7BreakOnStartup = false;
+    bool ARM9BreakOnStartup = false;
+};
+
 /// Arguments to pass into the NDS constructor.
 /// New fields here should have default values if possible.
 struct NDSArgs
@@ -78,6 +104,20 @@ struct NDSArgs
     /// Defaults to generated NDS firmware.
     /// Generated firmware is not compatible with DSi mode.
     melonDS::Firmware Firmware {0};
+
+    /// How the JIT should be configured when initializing.
+    /// Defaults to enabled, with default settings.
+    /// To disable the JIT, set this to std::nullopt.
+    /// Ignored in builds that don't have the JIT included.
+    std::optional<JITArgs> JIT = JITArgs();
+
+    AudioBitDepth BitDepth = AudioBitDepth::Auto;
+    AudioInterpolation Interpolation = AudioInterpolation::None;
+
+    /// How the GDB stub should be handled.
+    /// Defaults to disabled.
+    /// Ignored in builds that don't have the GDB stub included.
+    std::optional<GDBArgs> GDB = std::nullopt;
 };
 
 /// Arguments to pass into the DSi constructor.
@@ -95,6 +135,8 @@ struct DSiArgs final : public NDSArgs
     /// SD card to install.
     /// Defaults to std::nullopt, which means no SD card.
     std::optional<FATStorage> DSiSDCard;
+
+    bool FullBIOSBoot = false;
 };
 }
 #endif //MELONDS_ARGS_H
diff --git a/src/DSi.cpp b/src/DSi.cpp
index 5dcd419..a5403d2 100644
--- a/src/DSi.cpp
+++ b/src/DSi.cpp
@@ -111,6 +111,8 @@ void DSi::Reset()
     //ARM9.CP15Write(0x100, ARM9.CP15Read(0x100) | 0x00050000);
     NDS::Reset();
 
+    // The SOUNDBIAS register does nothing on DSi
+    SPU.SetApplyBias(false);
     KeyInput &= ~(1 << (16+6));
     MapSharedWRAM(3);
 
@@ -128,7 +130,7 @@ void DSi::Reset()
 
     AES.Reset();
 
-    if (Platform::GetConfigBool(Platform::DSi_FullBIOSBoot))
+    if (FullBIOSBoot)
     {
         SCFG_BIOS = 0x0000;
     }
@@ -679,7 +681,7 @@ void DSi::SoftReset()
 
     AES.Reset();
 
-    if (Platform::GetConfigBool(Platform::DSi_FullBIOSBoot))
+    if (FullBIOSBoot)
     {
         SCFG_BIOS = 0x0000;
     }
@@ -741,7 +743,7 @@ bool DSi::LoadNAND()
     memset(NWRAMMask, 0, sizeof(NWRAMMask));
 
     u32 bootparams[8];
-    if (Platform::GetConfigBool(Platform::DSi_FullBIOSBoot))
+    if (FullBIOSBoot)
     {
         // TODO: figure out default MBK mapping
         // MBK1..5: disable mappings
@@ -879,7 +881,7 @@ bool DSi::LoadNAND()
     Log(LogLevel::Debug, "eMMC CID: %08llX%08llX\n", *(const u64*)&emmccid[0], *(const u64*)&emmccid[8]);
     Log(LogLevel::Debug, "Console ID: %" PRIx64 "\n", image->GetConsoleID());
 
-    if (Platform::GetConfigBool(Platform::DSi_FullBIOSBoot))
+    if (FullBIOSBoot)
     {
         // point CPUs to boot ROM reset vectors
         ARM9.JumpTo(0xFFFF0000);
diff --git a/src/DSi.h b/src/DSi.h
index acd85c1..90bb0d4 100644
--- a/src/DSi.h
+++ b/src/DSi.h
@@ -172,7 +172,10 @@ public:
     u8 GPIO_IE;
     u8 GPIO_WiFi;
 
+    bool GetFullBIOSBoot() const noexcept { return FullBIOSBoot; }
+    void SetFullBIOSBoot(bool full) noexcept { FullBIOSBoot = full; }
 private:
+    bool FullBIOSBoot;
     void Set_SCFG_Clock9(u16 val);
     void Set_SCFG_MC(u32 val);
     void DecryptModcryptArea(u32 offset, u32 size, u8* iv);
diff --git a/src/NDS.cpp b/src/NDS.cpp
index f3e5a1a..54aa270 100644
--- a/src/NDS.cpp
+++ b/src/NDS.cpp
@@ -92,8 +92,8 @@ NDS::NDS(NDSArgs&& args, int type) noexcept :
     ConsoleType(type),
     ARM7BIOS(args.ARM7BIOS),
     ARM9BIOS(args.ARM9BIOS),
-    JIT(*this),
-    SPU(*this),
+    JIT(*this, args.JIT),
+    SPU(*this, args.BitDepth, args.Interpolation),
     GPU(*this),
     SPI(*this, std::move(args.Firmware)),
     RTC(*this),
@@ -101,8 +101,8 @@ NDS::NDS(NDSArgs&& args, int type) noexcept :
     NDSCartSlot(*this, std::move(args.NDSROM)),
     GBACartSlot(type == 1 ? nullptr : std::move(args.GBAROM)),
     AREngine(*this),
-    ARM9(*this),
-    ARM7(*this),
+    ARM9(*this, args.GDB, args.JIT.has_value()),
+    ARM7(*this, args.GDB, args.JIT.has_value()),
     DMAs {
         DMA(0, 0, *this),
         DMA(0, 1, *this),
@@ -203,6 +203,22 @@ void NDS::SetARM7RegionTimings(u32 addrstart, u32 addrend, u32 region, int buswi
     }
 }
 
+#ifdef JIT_ENABLED
+void NDS::SetJITArgs(std::optional<JITArgs> args) noexcept
+{
+    if (args)
+    { // If we want to turn the JIT on...
+        JIT.SetJITArgs(*args);
+    }
+    else if (args.has_value() != EnableJIT)
+    { // Else if we want to turn the JIT off, and it wasn't already off...
+        JIT.ResetBlockCache();
+    }
+
+    EnableJIT = args.has_value();
+}
+#endif
+
 void NDS::InitTimings()
 {
     // TODO, eventually:
@@ -249,12 +265,12 @@ bool NDS::NeedsDirectBoot()
     }
     else
     {
-        // internal BIOS does not support direct boot
-        if (!Platform::GetConfigBool(Platform::ExternalBIOSEnable))
+        // DSi/3DS firmwares aren't bootable, neither is the generated firmware
+        if (!SPI.GetFirmware().IsBootable())
             return true;
 
-        // DSi/3DS firmwares aren't bootable
-        if (!SPI.GetFirmware().IsBootable())
+        // FreeBIOS requires direct boot (it can't boot firmware)
+        if (IsLoadedARM7BIOSBuiltIn() || IsLoadedARM9BIOSBuiltIn())
             return true;
 
         return false;
@@ -394,10 +410,6 @@ void NDS::Reset()
     Platform::FileHandle* f;
     u32 i;
 
-#ifdef JIT_ENABLED
-    EnableJIT = Platform::GetConfigBool(Platform::JIT_Enable);
-#endif
-
     RunningGame = false;
     LastSysClockCycles = 0;
 
@@ -505,28 +517,6 @@ void NDS::Reset()
     SPI.Reset();
     RTC.Reset();
     Wifi.Reset();
-
-    // TODO: move the SOUNDBIAS/degrade logic to SPU?
-
-    // The SOUNDBIAS register does nothing on DSi
-    SPU.SetApplyBias(ConsoleType == 0);
-
-    bool degradeAudio = true;
-
-    if (ConsoleType == 1)
-    {
-        //DSi::Reset();
-        KeyInput &= ~(1 << (16+6));
-        degradeAudio = false;
-    }
-
-    int bitDepth = Platform::GetConfigInt(Platform::AudioBitDepth);
-    if (bitDepth == 1) // Always 10-bit
-        degradeAudio = true;
-    else if (bitDepth == 2) // Always 16-bit
-        degradeAudio = false;
-
-    SPU.SetDegrade10Bit(degradeAudio);
 }
 
 void NDS::Start()
diff --git a/src/NDS.h b/src/NDS.h
index b9f8291..c0b429e 100644
--- a/src/NDS.h
+++ b/src/NDS.h
@@ -219,11 +219,12 @@ class ARMJIT;
 
 class NDS
 {
-public:
-
+private:
 #ifdef JIT_ENABLED
     bool EnableJIT;
 #endif
+
+public:
     int ConsoleType;
     int CurCPU;
 
@@ -433,6 +434,11 @@ public:
     virtual void ARM7IOWrite16(u32 addr, u16 val);
     virtual void ARM7IOWrite32(u32 addr, u32 val);
 
+#ifdef JIT_ENABLED
+    [[nodiscard]] bool IsJITEnabled() const noexcept { return EnableJIT; }
+    void SetJITArgs(std::optional<JITArgs> args) noexcept;
+#endif
+
 private:
     void InitTimings();
     u32 SchedListMask;
diff --git a/src/NDSCart.cpp b/src/NDSCart.cpp
index 848c619..65309e3 100644
--- a/src/NDSCart.cpp
+++ b/src/NDSCart.cpp
@@ -109,9 +109,9 @@ void NDSCartSlot::Key1_ApplyKeycode(u32* keycode, u32 mod) noexcept
     }
 }
 
-void NDSCartSlot::Key1_LoadKeyBuf(bool dsi, bool externalBios, u8 *bios, u32 biosLength) noexcept
+void NDSCartSlot::Key1_LoadKeyBuf(bool dsi, u8 *bios, u32 biosLength) noexcept
 {
-    if (externalBios)
+    if (!NDS.IsLoadedARM7BIOSBuiltIn())
     {
         u32 expected_bios_length = dsi ? 0x10000 : 0x4000;
         if (biosLength != expected_bios_length)
@@ -138,7 +138,7 @@ void NDSCartSlot::Key1_LoadKeyBuf(bool dsi, bool externalBios, u8 *bios, u32 bio
 
 void NDSCartSlot::Key1_InitKeycode(bool dsi, u32 idcode, u32 level, u32 mod, u8 *bios, u32 biosLength) noexcept
 {
-    Key1_LoadKeyBuf(dsi, Platform::GetConfigBool(Platform::ExternalBIOSEnable), bios, biosLength);
+    Key1_LoadKeyBuf(dsi, bios, biosLength);
 
     u32 keycode[3] = {idcode, idcode>>1, idcode<<1};
     if (level >= 1) Key1_ApplyKeycode(keycode, mod);
diff --git a/src/NDSCart.h b/src/NDSCart.h
index 43bf1fc..03e16e9 100644
--- a/src/NDSCart.h
+++ b/src/NDSCart.h
@@ -357,7 +357,7 @@ private:
     void Key1_Encrypt(u32* data) noexcept;
     void Key1_Decrypt(u32* data) noexcept;
     void Key1_ApplyKeycode(u32* keycode, u32 mod) noexcept;
-    void Key1_LoadKeyBuf(bool dsi, bool externalBios, u8 *bios, u32 biosLength) noexcept;
+    void Key1_LoadKeyBuf(bool dsi, u8 *bios, u32 biosLength) noexcept;
     void Key1_InitKeycode(bool dsi, u32 idcode, u32 level, u32 mod, u8 *bios, u32 biosLength) noexcept;
     void Key2_Encrypt(u8* data, u32 len) noexcept;
     void ROMEndTransfer(u32 param) noexcept;
diff --git a/src/Platform.h b/src/Platform.h
index 2c9a6a4..21b3d46 100644
--- a/src/Platform.h
+++ b/src/Platform.h
@@ -92,39 +92,6 @@ int InstanceID();
  */
 std::string InstanceFileSuffix();
 
-// configuration values
-
-enum ConfigEntry
-{
-#ifdef JIT_ENABLED
-    JIT_Enable,
-    JIT_MaxBlockSize,
-    JIT_LiteralOptimizations,
-    JIT_BranchOptimizations,
-    JIT_FastMemory,
-#endif
-
-    ExternalBIOSEnable,
-
-    Firm_MAC,
-
-    AudioBitDepth,
-
-    DSi_FullBIOSBoot,
-
-#ifdef GDBSTUB_ENABLED
-    GdbEnabled,
-    GdbPortARM7,
-    GdbPortARM9,
-    GdbARM7BreakOnStartup,
-    GdbARM9BreakOnStartup,
-#endif
-};
-
-int GetConfigInt(ConfigEntry entry);
-bool GetConfigBool(ConfigEntry entry);
-bool GetConfigArray(ConfigEntry entry, void* data);
-
 /**
  * Denotes how a file will be opened and accessed.
  * Flags may or may not correspond to the operating system's file API.
diff --git a/src/SPU.cpp b/src/SPU.cpp
index 1ec3c90..f1df9cf 100644
--- a/src/SPU.cpp
+++ b/src/SPU.cpp
@@ -140,31 +140,32 @@ constexpr array2d<s16, 0x100, 4> InterpCubic = []() constexpr {
     return interp;
 }();
 
-SPU::SPU(melonDS::NDS& nds) :
+SPU::SPU(melonDS::NDS& nds, AudioBitDepth bitdepth, AudioInterpolation interpolation) :
     NDS(nds),
     Channels {
-        SPUChannel(0, nds),
-        SPUChannel(1, nds),
-        SPUChannel(2, nds),
-        SPUChannel(3, nds),
-        SPUChannel(4, nds),
-        SPUChannel(5, nds),
-        SPUChannel(6, nds),
-        SPUChannel(7, nds),
-        SPUChannel(8, nds),
-        SPUChannel(9, nds),
-        SPUChannel(10, nds),
-        SPUChannel(11, nds),
-        SPUChannel(12, nds),
-        SPUChannel(13, nds),
-        SPUChannel(14, nds),
-        SPUChannel(15, nds),
+        SPUChannel(0, nds, interpolation),
+        SPUChannel(1, nds, interpolation),
+        SPUChannel(2, nds, interpolation),
+        SPUChannel(3, nds, interpolation),
+        SPUChannel(4, nds, interpolation),
+        SPUChannel(5, nds, interpolation),
+        SPUChannel(6, nds, interpolation),
+        SPUChannel(7, nds, interpolation),
+        SPUChannel(8, nds, interpolation),
+        SPUChannel(9, nds, interpolation),
+        SPUChannel(10, nds, interpolation),
+        SPUChannel(11, nds, interpolation),
+        SPUChannel(12, nds, interpolation),
+        SPUChannel(13, nds, interpolation),
+        SPUChannel(14, nds, interpolation),
+        SPUChannel(15, nds, interpolation),
     },
     Capture {
         SPUCaptureUnit(0, nds),
         SPUCaptureUnit(1, nds),
     },
-    AudioLock(Platform::Mutex_Create())
+    AudioLock(Platform::Mutex_Create()),
+    Degrade10Bit(bitdepth == AudioBitDepth::_10Bit || (nds.ConsoleType == 1 && bitdepth == AudioBitDepth::Auto))
 {
     NDS.RegisterEventFunc(Event_SPU, 0, MemberEventFunc(SPU, Mix));
 
@@ -236,7 +237,7 @@ void SPU::SetPowerCnt(u32 val)
 }
 
 
-void SPU::SetInterpolation(int type)
+void SPU::SetInterpolation(AudioInterpolation type)
 {
     for (SPUChannel& channel : Channels)
         channel.InterpType = type;
@@ -257,8 +258,26 @@ void SPU::SetDegrade10Bit(bool enable)
     Degrade10Bit = enable;
 }
 
+void SPU::SetDegrade10Bit(AudioBitDepth depth)
+{
+    switch (depth)
+    {
+    case AudioBitDepth::Auto:
+        Degrade10Bit = (NDS.ConsoleType == 0);
+        break;
+    case AudioBitDepth::_10Bit:
+        Degrade10Bit = true;
+        break;
+    case AudioBitDepth::_16Bit:
+        Degrade10Bit = false;
+        break;
+    }
+}
 
-SPUChannel::SPUChannel(u32 num, melonDS::NDS& nds) : NDS(nds), Num(num)
+SPUChannel::SPUChannel(u32 num, melonDS::NDS& nds, AudioInterpolation interpolation) :
+    NDS(nds),
+    Num(num),
+    InterpType(interpolation)
 {
 }
 
@@ -559,7 +578,7 @@ s32 SPUChannel::Run()
         // for optional interpolation: save previous samples
         // the interpolated audio will be delayed by a couple samples,
         // but it's easier to deal with this way
-        if ((type < 3) && (InterpType != 0))
+        if ((type < 3) && (InterpType != AudioInterpolation::None))
         {
             PrevSample[2] = PrevSample[1];
             PrevSample[1] = PrevSample[0];
@@ -579,24 +598,24 @@ s32 SPUChannel::Run()
     s32 val = (s32)CurSample;
 
     // interpolation (emulation improvement, not a hardware feature)
-    if ((type < 3) && (InterpType != 0))
+    if ((type < 3) && (InterpType != AudioInterpolation::None))
     {
         s32 samplepos = ((Timer - TimerReload) * 0x100) / (0x10000 - TimerReload);
         if (samplepos > 0xFF) samplepos = 0xFF;
 
         switch (InterpType)
         {
-        case 1: // linear
+        case AudioInterpolation::Linear:
             val = ((val           * samplepos) +
                    (PrevSample[0] * (0xFF-samplepos))) >> 8;
             break;
 
-        case 2: // cosine
+        case AudioInterpolation::Cosine:
             val = ((val           * InterpCos[samplepos]) +
                    (PrevSample[0] * InterpCos[0xFF-samplepos])) >> 14;
             break;
 
-        case 3: // cubic
+        case AudioInterpolation::Cubic:
             val = ((PrevSample[2] * InterpCubic[samplepos][0]) +
                    (PrevSample[1] * InterpCubic[samplepos][1]) +
                    (PrevSample[0] * InterpCubic[samplepos][2]) +
diff --git a/src/SPU.h b/src/SPU.h
index 03d476e..1541c68 100644
--- a/src/SPU.h
+++ b/src/SPU.h
@@ -27,10 +27,25 @@ namespace melonDS
 class NDS;
 class SPU;
 
+enum class AudioBitDepth
+{
+    Auto,
+    _10Bit,
+    _16Bit,
+};
+
+enum class AudioInterpolation
+{
+    None,
+    Linear,
+    Cosine,
+    Cubic,
+};
+
 class SPUChannel
 {
 public:
-    SPUChannel(u32 num, melonDS::NDS& nds);
+    SPUChannel(u32 num, melonDS::NDS& nds, AudioInterpolation interpolation);
     void Reset();
     void DoSavestate(Savestate* file);
 
@@ -40,7 +55,7 @@ public:
 
     // audio interpolation is an improvement upon the original hardware
     // (which performs no interpolation)
-    int InterpType = 0;
+    AudioInterpolation InterpType = AudioInterpolation::None;
 
     const u32 Num;
 
@@ -200,7 +215,7 @@ private:
 class SPU
 {
 public:
-    explicit SPU(melonDS::NDS& nds);
+    explicit SPU(melonDS::NDS& nds, AudioBitDepth bitdepth, AudioInterpolation interpolation);
     ~SPU();
     void Reset();
     void DoSavestate(Savestate* file);
@@ -210,10 +225,11 @@ public:
     void SetPowerCnt(u32 val);
 
     // 0=none 1=linear 2=cosine 3=cubic
-    void SetInterpolation(int type);
+    void SetInterpolation(AudioInterpolation type);
 
     void SetBias(u16 bias);
     void SetDegrade10Bit(bool enable);
+    void SetDegrade10Bit(AudioBitDepth depth);
     void SetApplyBias(bool enable);
 
     void Mix(u32 dummy);
diff --git a/src/frontend/qt_sdl/AudioInOut.cpp b/src/frontend/qt_sdl/AudioInOut.cpp
index ae5529d..1f1ee1c 100644
--- a/src/frontend/qt_sdl/AudioInOut.cpp
+++ b/src/frontend/qt_sdl/AudioInOut.cpp
@@ -369,7 +369,7 @@ void UpdateSettings(NDS& nds)
 {
     MicClose();
 
-    nds.SPU.SetInterpolation(Config::AudioInterp);
+    nds.SPU.SetInterpolation(static_cast<AudioInterpolation>(Config::AudioInterp));
     SetupMicInputData();
 
     MicOpen();
diff --git a/src/frontend/qt_sdl/Platform.cpp b/src/frontend/qt_sdl/Platform.cpp
index d410d4f..4630582 100644
--- a/src/frontend/qt_sdl/Platform.cpp
+++ b/src/frontend/qt_sdl/Platform.cpp
@@ -193,90 +193,6 @@ std::string InstanceFileSuffix()
     return suffix;
 }
 
-
-int GetConfigInt(ConfigEntry entry)
-{
-    const int imgsizes[] = {0, 256, 512, 1024, 2048, 4096};
-
-    switch (entry)
-    {
-#ifdef JIT_ENABLED
-    case JIT_MaxBlockSize: return Config::JIT_MaxBlockSize;
-#endif
-
-    case AudioBitDepth: return Config::AudioBitDepth;
-
-#ifdef GDBSTUB_ENABLED
-    case GdbPortARM7: return Config::GdbPortARM7;
-    case GdbPortARM9: return Config::GdbPortARM9;
-#endif
-    }
-
-    return 0;
-}
-
-bool GetConfigBool(ConfigEntry entry)
-{
-    switch (entry)
-    {
-#ifdef JIT_ENABLED
-    case JIT_Enable: return Config::JIT_Enable != 0;
-    case JIT_LiteralOptimizations: return Config::JIT_LiteralOptimisations != 0;
-    case JIT_BranchOptimizations: return Config::JIT_BranchOptimisations != 0;
-    case JIT_FastMemory: return Config::JIT_FastMemory != 0;
-#endif
-
-    case ExternalBIOSEnable: return Config::ExternalBIOSEnable != 0;
-
-    case DSi_FullBIOSBoot: return Config::DSiFullBIOSBoot != 0;
-
-#ifdef GDBSTUB_ENABLED
-    case GdbEnabled: return Config::GdbEnabled;
-    case GdbARM7BreakOnStartup: return Config::GdbARM7BreakOnStartup;
-    case GdbARM9BreakOnStartup: return Config::GdbARM9BreakOnStartup;
-#endif
-    }
-
-    return false;
-}
-
-bool GetConfigArray(ConfigEntry entry, void* data)
-{
-    switch (entry)
-    {
-    case Firm_MAC:
-        {
-            std::string& mac_in = Config::FirmwareMAC;
-            u8* mac_out = (u8*)data;
-
-            int o = 0;
-            u8 tmp = 0;
-            for (int i = 0; i < 18; i++)
-            {
-                char c = mac_in[i];
-                if (c == '\0') break;
-
-                int n;
-                if      (c >= '0' && c <= '9') n = c - '0';
-                else if (c >= 'a' && c <= 'f') n = c - 'a' + 10;
-                else if (c >= 'A' && c <= 'F') n = c - 'A' + 10;
-                else continue;
-
-                if (!(o & 1))
-                    tmp = n;
-                else
-                    mac_out[o >> 1] = n | (tmp << 4);
-
-                o++;
-                if (o >= 12) return true;
-            }
-        }
-        return false;
-    }
-
-    return false;
-}
-
 constexpr char AccessMode(FileMode mode, bool file_exists)
 {
     if (!(mode & FileMode::Write))
diff --git a/src/frontend/qt_sdl/ROMManager.cpp b/src/frontend/qt_sdl/ROMManager.cpp
index fda043a..b065ad1 100644
--- a/src/frontend/qt_sdl/ROMManager.cpp
+++ b/src/frontend/qt_sdl/ROMManager.cpp
@@ -1078,6 +1078,36 @@ pair<unique_ptr<Firmware>, string> GenerateDefaultFirmware()
     return std::make_pair(std::move(firmware), std::move(wfcsettingspath));
 }
 
+bool ParseMacAddress(void* data)
+{
+    const std::string& mac_in = Config::FirmwareMAC;
+    u8* mac_out = (u8*)data;
+
+    int o = 0;
+    u8 tmp = 0;
+    for (int i = 0; i < 18; i++)
+    {
+        char c = mac_in[i];
+        if (c == '\0') break;
+
+        int n;
+        if      (c >= '0' && c <= '9') n = c - '0';
+        else if (c >= 'a' && c <= 'f') n = c - 'a' + 10;
+        else if (c >= 'A' && c <= 'F') n = c - 'A' + 10;
+        else continue;
+
+        if (!(o & 1))
+            tmp = n;
+        else
+            mac_out[o >> 1] = n | (tmp << 4);
+
+        o++;
+        if (o >= 12) return true;
+    }
+
+    return false;
+}
+
 void CustomizeFirmware(Firmware& firmware) noexcept
 {
     auto& currentData = firmware.GetEffectiveUserData();
@@ -1136,7 +1166,7 @@ void CustomizeFirmware(Firmware& firmware) noexcept
 
 
     MacAddress configuredMac;
-    rep = Platform::GetConfigArray(Platform::Firm_MAC, &configuredMac);
+    rep = ParseMacAddress(&configuredMac);
     rep &= (configuredMac != MacAddress());
 
     if (rep)
diff --git a/src/frontend/qt_sdl/main.cpp b/src/frontend/qt_sdl/main.cpp
index 5bd4d1b..30ea0ab 100644
--- a/src/frontend/qt_sdl/main.cpp
+++ b/src/frontend/qt_sdl/main.cpp
@@ -222,12 +222,42 @@ std::unique_ptr<NDS> EmuThread::CreateConsole(
     if (!firmware)
         return nullptr;
 
+#ifdef JIT_ENABLED
+    JITArgs jitargs {
+        static_cast<unsigned>(Config::JIT_MaxBlockSize),
+        Config::JIT_LiteralOptimisations,
+        Config::JIT_BranchOptimisations,
+        Config::JIT_FastMemory,
+    };
+#endif
+
+#ifdef GDBSTUB_ENABLED
+    GDBArgs gdbargs {
+        static_cast<u16>(Config::GdbPortARM7),
+        static_cast<u16>(Config::GdbPortARM9),
+        Config::GdbARM7BreakOnStartup,
+        Config::GdbARM9BreakOnStartup,
+    };
+#endif
+
     NDSArgs ndsargs {
         std::move(ndscart),
         std::move(gbacart),
         *arm9bios,
         *arm7bios,
         std::move(*firmware),
+#ifdef JIT_ENABLED
+        Config::JIT_Enable ? std::make_optional(jitargs) : std::nullopt,
+#else
+        std::nullopt,
+#endif
+        static_cast<AudioBitDepth>(Config::AudioBitDepth),
+        static_cast<AudioInterpolation>(Config::AudioInterp),
+#ifdef GDBSTUB_ENABLED
+        Config::GdbEnabled ? std::make_optional(gdbargs) : std::nullopt,
+#else
+        std::nullopt,
+#endif
     };
 
     if (Config::ConsoleType == 1)
@@ -251,6 +281,7 @@ std::unique_ptr<NDS> EmuThread::CreateConsole(
             *arm7ibios,
             std::move(*nand),
             std::move(sdcard),
+            Config::DSiFullBIOSBoot,
         };
 
         args.GBAROM = nullptr;
@@ -339,6 +370,7 @@ bool EmuThread::UpdateConsole(UpdateConsoleNDSArgs&& ndsargs, UpdateConsoleGBAAr
 
         auto dsisdcard = ROMManager::LoadDSiSDCard();
 
+        dsi.SetFullBIOSBoot(Config::DSiFullBIOSBoot);
         dsi.ARM7iBIOS = *arm7ibios;
         dsi.ARM9iBIOS = *arm9ibios;
         dsi.SetNAND(std::move(*nandimage));
@@ -354,10 +386,19 @@ bool EmuThread::UpdateConsole(UpdateConsoleNDSArgs&& ndsargs, UpdateConsoleGBAAr
         NDS->SetGBACart(std::move(nextgbacart));
     }
 
+    JITArgs jitargs {
+        static_cast<unsigned>(Config::JIT_MaxBlockSize),
+        Config::JIT_LiteralOptimisations,
+        Config::JIT_BranchOptimisations,
+        Config::JIT_FastMemory,
+    };
     NDS->ARM7BIOS = *arm7bios;
     NDS->ARM9BIOS = *arm9bios;
     NDS->SetFirmware(std::move(*firmware));
     NDS->SetNDSCart(std::move(nextndscart));
+    NDS->SetJITArgs(Config::JIT_Enable ? std::make_optional(jitargs) : std::nullopt);
+    NDS->SPU.SetInterpolation(static_cast<AudioInterpolation>(Config::AudioInterp));
+    NDS->SPU.SetDegrade10Bit(static_cast<AudioBitDepth>(Config::AudioBitDepth));
 
     NDS::Current = NDS.get();
 
@@ -510,8 +551,6 @@ void EmuThread::run()
         NDS->GPU.SetRenderer3D(std::move(glrenderer));
     }
 
-    NDS->SPU.SetInterpolation(Config::AudioInterp);
-
     Input::Init();
 
     u32 nframes = 0;
@@ -3137,7 +3176,7 @@ void MainWindow::onPathSettingsFinished(int res)
 void MainWindow::onUpdateAudioSettings()
 {
     assert(emuThread->NDS != nullptr);
-    emuThread->NDS->SPU.SetInterpolation(Config::AudioInterp);
+    emuThread->NDS->SPU.SetInterpolation(static_cast<AudioInterpolation>(Config::AudioInterp));
 
     if (Config::AudioBitDepth == 0)
         emuThread->NDS->SPU.SetDegrade10Bit(emuThread->NDS->ConsoleType == 0);