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#ifndef M68K__HEADER
#define M68K__HEADER
struct m68ki_cpu_core_s;
/* ======================================================================== */
/* ========================= LICENSING & COPYRIGHT ======================== */
/* ======================================================================== */
/*
* MUSASHI
* Version 3.3
*
* A portable Motorola M680x0 processor emulation engine.
* Copyright 1998-2001 Karl Stenerud. All rights reserved.
*
* This code may be freely used for non-commercial purposes as long as this
* copyright notice remains unaltered in the source code and any binary files
* containing this code in compiled form.
*
* All other lisencing terms must be negotiated with the author
* (Karl Stenerud).
*
* The latest version of this code can be obtained at:
* http://kstenerud.cjb.net
*/
/* ======================================================================== */
/* ============================ GENERAL DEFINES =========================== */
/* ======================================================================== */
/* There are 7 levels of interrupt to the 68K.
* A transition from < 7 to 7 will cause a non-maskable interrupt (NMI).
*/
#define M68K_IRQ_NONE 0
#define M68K_IRQ_1 1
#define M68K_IRQ_2 2
#define M68K_IRQ_3 3
#define M68K_IRQ_4 4
#define M68K_IRQ_5 5
#define M68K_IRQ_6 6
#define M68K_IRQ_7 7
/* Special interrupt acknowledge values.
* Use these as special returns from the interrupt acknowledge callback
* (specified later in this header).
*/
/* Causes an interrupt autovector (0x18 + interrupt level) to be taken.
* This happens in a real 68K if VPA or AVEC is asserted during an interrupt
* acknowledge cycle instead of DTACK.
*/
#define M68K_INT_ACK_AUTOVECTOR 0xffffffff
/* Causes the spurious interrupt vector (0x18) to be taken
* This happens in a real 68K if BERR is asserted during the interrupt
* acknowledge cycle (i.e. no devices responded to the acknowledge).
*/
#define M68K_INT_ACK_SPURIOUS 0xfffffffe
/* CPU types for use in m68k_set_cpu_type() */
enum
{
M68K_CPU_TYPE_INVALID,
M68K_CPU_TYPE_68000,
M68K_CPU_TYPE_68010,
M68K_CPU_TYPE_68EC020,
M68K_CPU_TYPE_68020,
M68K_CPU_TYPE_68030, /* Supported by disassembler ONLY */
M68K_CPU_TYPE_68040 /* Supported by disassembler ONLY */
};
/* Registers used by m68k_get_reg() and m68k_set_reg() */
typedef enum
{
/* Real registers */
M68K_REG_D0, /* Data registers */
M68K_REG_D1,
M68K_REG_D2,
M68K_REG_D3,
M68K_REG_D4,
M68K_REG_D5,
M68K_REG_D6,
M68K_REG_D7,
M68K_REG_A0, /* Address registers */
M68K_REG_A1,
M68K_REG_A2,
M68K_REG_A3,
M68K_REG_A4,
M68K_REG_A5,
M68K_REG_A6,
M68K_REG_A7,
M68K_REG_PC, /* Program Counter */
M68K_REG_SR, /* Status Register */
M68K_REG_SP, /* The current Stack Pointer (located in A7) */
M68K_REG_USP, /* User Stack Pointer */
M68K_REG_ISP, /* Interrupt Stack Pointer */
M68K_REG_MSP, /* Master Stack Pointer */
M68K_REG_SFC, /* Source Function Code */
M68K_REG_DFC, /* Destination Function Code */
M68K_REG_VBR, /* Vector Base Register */
M68K_REG_CACR, /* Cache Control Register */
M68K_REG_CAAR, /* Cache Address Register */
/* Assumed registers */
/* These are cheat registers which emulate the 1-longword prefetch
* present in the 68000 and 68010.
*/
M68K_REG_PREF_ADDR, /* Last prefetch address */
M68K_REG_PREF_DATA, /* Last prefetch data */
/* Convenience registers */
M68K_REG_PPC, /* Previous value in the program counter */
M68K_REG_IR, /* Instruction register */
M68K_REG_CPU_TYPE /* Type of CPU being run */
} m68k_register_t;
/* ======================================================================== */
/* ====================== FUNCTIONS CALLED BY THE CPU ===================== */
/* ======================================================================== */
/* You will have to implement these functions */
/* read/write functions called by the CPU to access memory.
* while values used are 32 bits, only the appropriate number
* of bits are relevant (i.e. in write_memory_8, only the lower 8 bits
* of value should be written to memory).
*
* NOTE: I have separated the immediate and PC-relative memory fetches
* from the other memory fetches because some systems require
* differentiation between PROGRAM and DATA fetches (usually
* for security setups such as encryption).
* This separation can either be achieved by setting
* M68K_SEPARATE_READS in m68kconf.h and defining
* the read functions, or by setting M68K_EMULATE_FC and
* making a function code callback function.
* Using the callback offers better emulation coverage
* because you can also monitor whether the CPU is in SYSTEM or
* USER mode, but it is also slower.
*/
/* Read from anywhere */
unsigned int m68k_read_memory_8(struct m68ki_cpu_core_s *cpu, unsigned int address);
unsigned int m68k_read_memory_16(struct m68ki_cpu_core_s *cpu, unsigned int address);
unsigned int m68k_read_memory_32(struct m68ki_cpu_core_s *cpu, unsigned int address);
/* Read data immediately following the PC */
//INLINE unsigned int m68k_read_immediate_16(unsigned int address);
//INLINE unsigned int m68k_read_immediate_32(unsigned int address);
/* Read data relative to the PC */
//INLINE unsigned int m68k_read_pcrelative_8(unsigned int address);
//INLINE unsigned int m68k_read_pcrelative_16(unsigned int address);
//INLINE unsigned int m68k_read_pcrelative_32(unsigned int address);
/* Memory access for the disassembler */
unsigned int m68k_read_disassembler_8 (struct m68ki_cpu_core_s *cpu, unsigned int address);
unsigned int m68k_read_disassembler_16 (struct m68ki_cpu_core_s *cpu, unsigned int address);
unsigned int m68k_read_disassembler_32 (struct m68ki_cpu_core_s *cpu, unsigned int address);
/* Write to anywhere */
void m68k_write_memory_8(struct m68ki_cpu_core_s *cpu, unsigned int address, unsigned int value);
void m68k_write_memory_16(struct m68ki_cpu_core_s *cpu, unsigned int address, unsigned int value);
void m68k_write_memory_32(struct m68ki_cpu_core_s *cpu, unsigned int address, unsigned int value);
/* Special call to simulate undocumented 68k behavior when move.l with a
* predecrement destination mode is executed.
* To simulate real 68k behavior, first write the high word to
* [address+2], and then write the low word to [address].
*
* Enable this functionality with M68K_SIMULATE_PD_WRITES in m68kconf.h.
*/
//INLINE void m68k_write_memory_32_pd(unsigned int address, unsigned int value);
/* ======================================================================== */
/* ============================== CALLBACKS =============================== */
/* ======================================================================== */
/* These functions allow you to set callbacks to the host when specific events
* occur. Note that you must enable the corresponding value in m68kconf.h
* in order for these to do anything useful.
* Note: I have defined default callbacks which are used if you have enabled
* the corresponding #define in m68kconf.h but either haven't assigned a
* callback or have assigned a callback of NULL.
*/
/* Set the callback for an interrupt acknowledge.
* You must enable M68K_EMULATE_INT_ACK in m68kconf.h.
* The CPU will call the callback with the interrupt level being acknowledged.
* The host program must return either a vector from 0x02-0xff, or one of the
* special interrupt acknowledge values specified earlier in this header.
* If this is not implemented, the CPU will always assume an autovectored
* interrupt, and will automatically clear the interrupt request when it
* services the interrupt.
* Default behavior: return M68K_INT_ACK_AUTOVECTOR.
*/
void m68k_set_int_ack_callback(struct m68ki_cpu_core_s *cpu, int (*callback)(struct m68ki_cpu_core_s *cpu, int int_level));
/* Set the callback for a breakpoint acknowledge (68010+).
* You must enable M68K_EMULATE_BKPT_ACK in m68kconf.h.
* The CPU will call the callback with whatever was in the data field of the
* BKPT instruction for 68020+, or 0 for 68010.
* Default behavior: do nothing.
*/
void m68k_set_bkpt_ack_callback(struct m68ki_cpu_core_s *cpu, void (*callback)(struct m68ki_cpu_core_s *cpu, unsigned int data));
/* Set the callback for the RESET instruction.
* You must enable M68K_EMULATE_RESET in m68kconf.h.
* The CPU calls this callback every time it encounters a RESET instruction.
* Default behavior: do nothing.
*/
void m68k_set_reset_instr_callback(struct m68ki_cpu_core_s *cpu, void (*callback)(struct m68ki_cpu_core_s *cpu));
/* Set the callback for informing of a large PC change.
* You must enable M68K_MONITOR_PC in m68kconf.h.
* The CPU calls this callback with the new PC value every time the PC changes
* by a large value (currently set for changes by longwords).
* Default behavior: do nothing.
*/
void m68k_set_pc_changed_callback(struct m68ki_cpu_core_s *cpu, void (*callback)(struct m68ki_cpu_core_s *cpu, unsigned int new_pc));
/* Set the callback for CPU function code changes.
* You must enable M68K_EMULATE_FC in m68kconf.h.
* The CPU calls this callback with the function code before every memory
* access to set the CPU's function code according to what kind of memory
* access it is (supervisor/user, program/data and such).
* Default behavior: do nothing.
*/
void m68k_set_fc_callback(struct m68ki_cpu_core_s *cpu, void (*callback)(struct m68ki_cpu_core_s *cpu, unsigned int new_fc));
/* Set a callback for the instruction cycle of the CPU.
* You must enable M68K_INSTRUCTION_HOOK in m68kconf.h.
* The CPU calls this callback just before fetching the opcode in the
* instruction cycle.
* Default behavior: do nothing.
*/
void m68k_set_instr_hook_callback(struct m68ki_cpu_core_s *cpu, void (*callback)(struct m68ki_cpu_core_s *cpu));
/* ======================================================================== */
/* ====================== FUNCTIONS TO ACCESS THE CPU ===================== */
/* ======================================================================== */
/* Use this function to set the CPU type you want to emulate.
* Currently supported types are: M68K_CPU_TYPE_68000, M68K_CPU_TYPE_68010,
* M68K_CPU_TYPE_EC020, and M68K_CPU_TYPE_68020.
*/
void m68k_set_cpu_type(struct m68ki_cpu_core_s *cpu, unsigned int cpu_type);
/* Do whatever initialisations the core requires. Should be called
* at least once at init time.
*/
struct m68ki_cpu_core_s *m68k_init(void);
/* Pulse the RESET pin on the CPU.
* You *MUST* reset the CPU at least once to initialize the emulation
* Note: If you didn't call m68k_set_cpu_type() before resetting
* the CPU for the first time, the CPU will be set to
* M68K_CPU_TYPE_68000.
*/
void m68k_pulse_reset(struct m68ki_cpu_core_s *cpu);
/* execute num_cycles worth of instructions. returns number of cycles used */
int m68k_execute(struct m68ki_cpu_core_s *cpu, int num_cycles);
/* These functions let you read/write/modify the number of cycles left to run
* while m68k_execute() is running.
* These are useful if the 68k accesses a memory-mapped port on another device
* that requires immediate processing by another CPU.
*/
int m68k_cycles_run(struct m68ki_cpu_core_s *cpu); /* Number of cycles run so far */
int m68k_cycles_remaining(struct m68ki_cpu_core_s *cpu); /* Number of cycles left */
void m68k_modify_timeslice(struct m68ki_cpu_core_s *cpu, int cycles); /* Modify cycles left */
void m68k_end_timeslice(struct m68ki_cpu_core_s *cpu); /* End timeslice now */
/* Set the IPL0-IPL2 pins on the CPU (IRQ).
* A transition from < 7 to 7 will cause a non-maskable interrupt (NMI).
* Setting IRQ to 0 will clear an interrupt request.
*/
void m68k_set_irq(struct m68ki_cpu_core_s *cpu, unsigned int int_level);
/* Halt the CPU as if you pulsed the HALT pin. */
void m68k_pulse_halt(struct m68ki_cpu_core_s *cpu);
#if 0
/* Context switching to allow multiple CPUs */
/* Get the size of the cpu context in bytes */
unsigned int m68k_context_size(struct m68ki_cpu_core_s *cpu);
/* Get a cpu context */
unsigned int m68k_get_context(struct m68ki_cpu_core_s *cpu, void* dst);
/* set the current cpu context */
void m68k_set_context(struct m68ki_cpu_core_s *cpu, void* dst);
#endif
/* Register the CPU state information */
void m68k_state_register(struct m68ki_cpu_core_s *cpu, const char *type);
/* Peek at the internals of a CPU context. This can either be a context
* retrieved using m68k_get_context() or the currently running context.
* If context is NULL, the currently running CPU context will be used.
*/
unsigned int m68k_get_reg(struct m68ki_cpu_core_s *cpu, void* context, m68k_register_t reg);
/* Poke values into the internals of the currently running CPU context */
void m68k_set_reg(struct m68ki_cpu_core_s *cpu, m68k_register_t reg, unsigned int value);
/* Check if an instruction is valid for the specified CPU type */
unsigned int m68k_is_valid_instruction(struct m68ki_cpu_core_s *cpu, unsigned int instruction, unsigned int cpu_type);
/* Disassemble 1 instruction using the epecified CPU type at pc. Stores
* disassembly in str_buff and returns the size of the instruction in bytes.
*/
unsigned int m68k_disassemble(struct m68ki_cpu_core_s *cpu, char* str_buff, unsigned int pc, unsigned int cpu_type);
/* ======================================================================== */
/* ============================= CONFIGURATION ============================ */
/* ======================================================================== */
/* Import the configuration for this build */
#include "m68kconf.h"
/* ======================================================================== */
/* ============================== END OF FILE ============================= */
/* ======================================================================== */
#endif /* M68K__HEADER */
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