Merge pull request #792 from TomHarte/BIOSFreeMasterSystem

Ensures the Master System makes a genuine attempt to boot sans BIOS

Analyser/Dynamic/MultiMachine/Implementation/MultiJoystickMachine.cpp

@@ -25,7 +25,7 @@ class MultiJoystick: public Inputs::Joystick {
 			}
 		}
 
-		std::vector<Input> &get_inputs() final {
+		const std::vector<Input> &get_inputs() final {
 			if(inputs.empty()) {
 				for(const auto &joystick: joysticks_) {
 					std::vector<Input> joystick_inputs = joystick->get_inputs();

Components/9918/Implementation/9918Base.hpp

@@ -51,7 +51,7 @@ class Base {
 		}
 
 	protected:
-		const static int output_lag = 11;	// i.e. pixel output will occur 11 cycles after corresponding data read.
+		static constexpr int output_lag = 11;	// i.e. pixel output will occur 11 cycles after corresponding data read.
 
 		// The default TMS palette.
 		const uint32_t palette[16] = {

Inputs/Joystick.hpp

@@ -98,7 +98,7 @@ class Joystick {
 		};
 
 		/// @returns The list of all inputs defined on this joystick.
-		virtual std::vector<Input> &get_inputs() = 0;
+		virtual const std::vector<Input> &get_inputs() = 0;
 
 		/*!
 			Sets the digital value of @c input. This may have direct effect or
@@ -170,7 +170,7 @@ class ConcreteJoystick: public Joystick {
 			}
 		}
 
-		std::vector<Input> &get_inputs() final {
+		const std::vector<Input> &get_inputs() final {
 			return inputs_;
 		}
 
@@ -223,7 +223,7 @@ class ConcreteJoystick: public Joystick {
 		}
 
 	private:
-		std::vector<Input> inputs_;
+		const std::vector<Input> inputs_;
 
 		enum class StickType {
 			Digital,

Inputs/Keyboard.hpp

@@ -80,10 +80,11 @@ class Keyboard {
 
 	private:
 		std::set<Key> observed_keys_;
-		std::set<Key> essential_modifiers_;
+		const std::set<Key> essential_modifiers_;
+		const bool is_exclusive_ = true;
+
 		std::vector<bool> key_states_;
 		Delegate *delegate_ = nullptr;
-		bool is_exclusive_ = true;
 };
 
 }

Machines/Atari/2600/Atari2600.cpp

@@ -29,8 +29,8 @@
 #include "Cartridges/Unpaged.hpp"
 
 namespace {
-	static const double NTSC_clock_rate = 1194720;
+	static constexpr double NTSC_clock_rate = 1194720;
-	static const double PAL_clock_rate = 1182298;
+	static constexpr double PAL_clock_rate = 1182298;
 }
 
 namespace Atari2600 {

Machines/KeyboardMachine.hpp

@@ -121,13 +121,13 @@ class MappedKeyboardMachine: public Inputs::Keyboard::Delegate, public KeyboardM
 		};
 
 		/// Terminates a key sequence from the character mapper.
-		static const uint16_t KeyEndSequence = 0xffff;
+		static constexpr uint16_t KeyEndSequence = 0xffff;
 
 		/*!
 			Indicates that a key is not mapped (for the keyboard mapper) or that a
 			character cannot be typed (for the character mapper).
 		*/
-		static const uint16_t KeyNotMapped = 0xfffe;
+		static constexpr uint16_t KeyNotMapped = 0xfffe;
 
 		/*!
 			Allows individual machines to provide the mapping between host keys

Machines/MasterSystem/MasterSystem.cpp

@@ -133,30 +133,31 @@ class ConcreteMachine:
 				paging_registers_[2] = 0;
 			}
 
-			// Load the BIOS if relevant.
+			// Load the BIOS if available.
-			if(has_bios()) {
+			//
-				// TODO: there's probably a million other versions of the Master System BIOS; try to build a
+			// TODO: there's probably a million other versions of the Master System BIOS; try to build a
-				// CRC32 catalogue of those. So far:
+			// CRC32 catalogue of those. So far:
-				//
+			//
-				//	0072ed54 = US/European BIOS 1.3
+			//	0072ed54 = US/European BIOS 1.3
-				//	48d44a13 = Japanese BIOS 2.1
+			//	48d44a13 = Japanese BIOS 2.1
-				const bool is_japanese = target.region == Target::Region::Japan;
+			const bool is_japanese = target.region == Target::Region::Japan;
-				const auto roms = rom_fetcher(
+			const auto roms = rom_fetcher(
-					{ {"MasterSystem",
+				{ {"MasterSystem",
-						is_japanese ? "the Japanese Master System BIOS" : "the European/US Master System BIOS",
+					is_japanese ? "the Japanese Master System BIOS" : "the European/US Master System BIOS",
-						is_japanese ? "japanese-bios.sms" : "bios.sms",
+					is_japanese ? "japanese-bios.sms" : "bios.sms",
-						8*1024,
+					8*1024,
-						{ is_japanese ? 0x48d44a13u : 0x0072ed54u }
+					{ is_japanese ? 0x48d44a13u : 0x0072ed54u }
-					} }
+				} }
-				);
+			);
-				if(!roms[0]) {
+			if(!roms[0]) {
-					// No BIOS found; attempt to boot as though it has already disabled itself.
+				// No BIOS found; attempt to boot as though it has already disabled itself.
-					memory_control_ |= 0x08;
+				has_bios_ = false;
-					std::cerr << "No BIOS found; attempting to start cartridge directly" << std::endl;
+				memory_control_ |= 0x08;
-				} else {
+				std::cerr << "No BIOS found; attempting to start cartridge directly" << std::endl;
-					roms[0]->resize(8*1024);
+			} else {
-					memcpy(&bios_, roms[0]->data(), roms[0]->size());
+				has_bios_ = true;
-				}
+				roms[0]->resize(8*1024);
+				memcpy(&bios_, roms[0]->data(), roms[0]->size());
 			}
 			page_cartridge();
 
@@ -486,9 +487,9 @@ class ConcreteMachine:
 		}
 
 		using Target = Analyser::Static::Sega::Target;
-		Target::Model model_;
+		const Target::Model model_;
-		Target::Region region_;
+		const Target::Region region_;
-		Target::PagingScheme paging_scheme_;
+		const Target::PagingScheme paging_scheme_;
 		CPU::Z80::Processor<ConcreteMachine, false, false> z80_;
 		JustInTimeActor<TI::TMS::TMS9918> vdp_;
 
@@ -550,13 +551,11 @@ class ConcreteMachine:
 			}
 
 			// Throw the BIOS on top if this machine has one and it isn't disabled.
-			if(has_bios() && !(memory_control_ & 0x08)) {
+			if(has_bios_ && !(memory_control_ & 0x08)) {
 				map(read_pointers_, bios_, 8*1024, 0);
 			}
 		}
-		bool has_bios() {
+		bool has_bios_ = true;
-			return is_master_system(model_) && region_ != Target::Region::Japan;
-		}
 };
 
 }

Outputs/CRT/CRT.hpp

@@ -83,7 +83,7 @@ class CRT {
 
 		Outputs::Display::ScanTarget *scan_target_ = &Outputs::Display::NullScanTarget::singleton;
 		Outputs::Display::ScanTarget::Modals scan_target_modals_;
-		static const uint8_t DefaultAmplitude = 80;
+		static constexpr uint8_t DefaultAmplitude = 80;
 
 #ifndef NDEBUG
 		size_t allocated_data_length_ = std::numeric_limits<size_t>::min();

Processors/68000/68000.hpp

@@ -91,7 +91,7 @@ struct Microcycle {
 	/// Provides the 68000's bus grant line — indicating whether a bus request has been acknowledged.
 	static constexpr int BusGrant				= 1 << 10;
 
-	/// Contains a valid combination of the various static const int flags, describing the operation
+	/// Contains a valid combination of the various static constexpr int flags, describing the operation
 	/// performed by this Microcycle.
 	int operation = 0;
 

Processors/68000/Implementation/68000Storage.hpp

@@ -323,7 +323,7 @@ class ProcessorStorage {
 			static constexpr int DestinationMask = 1 << 6;
 			uint8_t action = uint8_t(Action::None);
 
-			static const uint16_t NoBusProgram = std::numeric_limits<uint16_t>::max();
+			static constexpr uint16_t NoBusProgram = std::numeric_limits<uint16_t>::max();
 			uint16_t bus_program = NoBusProgram;
 
 			MicroOp() {}