Sat, 27 Nov 2010 01:13:12 +0000
initial commit
1 #ifndef M68K__HEADER
2 #define M68K__HEADER
4 /* ======================================================================== */
5 /* ========================= LICENSING & COPYRIGHT ======================== */
6 /* ======================================================================== */
7 /*
8 * MUSASHI
9 * Version 3.3
10 *
11 * A portable Motorola M680x0 processor emulation engine.
12 * Copyright 1998-2001 Karl Stenerud. All rights reserved.
13 *
14 * This code may be freely used for non-commercial purposes as long as this
15 * copyright notice remains unaltered in the source code and any binary files
16 * containing this code in compiled form.
17 *
18 * All other lisencing terms must be negotiated with the author
19 * (Karl Stenerud).
20 *
21 * The latest version of this code can be obtained at:
22 * http://kstenerud.cjb.net
23 */
27 /* ======================================================================== */
28 /* ============================ GENERAL DEFINES =========================== */
30 /* ======================================================================== */
32 /* There are 7 levels of interrupt to the 68K.
33 * A transition from < 7 to 7 will cause a non-maskable interrupt (NMI).
34 */
35 #define M68K_IRQ_NONE 0
36 #define M68K_IRQ_1 1
37 #define M68K_IRQ_2 2
38 #define M68K_IRQ_3 3
39 #define M68K_IRQ_4 4
40 #define M68K_IRQ_5 5
41 #define M68K_IRQ_6 6
42 #define M68K_IRQ_7 7
45 /* Special interrupt acknowledge values.
46 * Use these as special returns from the interrupt acknowledge callback
47 * (specified later in this header).
48 */
50 /* Causes an interrupt autovector (0x18 + interrupt level) to be taken.
51 * This happens in a real 68K if VPA or AVEC is asserted during an interrupt
52 * acknowledge cycle instead of DTACK.
53 */
54 #define M68K_INT_ACK_AUTOVECTOR 0xffffffff
56 /* Causes the spurious interrupt vector (0x18) to be taken
57 * This happens in a real 68K if BERR is asserted during the interrupt
58 * acknowledge cycle (i.e. no devices responded to the acknowledge).
59 */
60 #define M68K_INT_ACK_SPURIOUS 0xfffffffe
63 /* CPU types for use in m68k_set_cpu_type() */
64 enum
65 {
66 M68K_CPU_TYPE_INVALID,
67 M68K_CPU_TYPE_68000,
68 M68K_CPU_TYPE_68010,
69 M68K_CPU_TYPE_68EC020,
70 M68K_CPU_TYPE_68020,
71 M68K_CPU_TYPE_68030, /* Supported by disassembler ONLY */
72 M68K_CPU_TYPE_68040 /* Supported by disassembler ONLY */
73 };
75 /* Registers used by m68k_get_reg() and m68k_set_reg() */
76 typedef enum
77 {
78 /* Real registers */
79 M68K_REG_D0, /* Data registers */
80 M68K_REG_D1,
81 M68K_REG_D2,
82 M68K_REG_D3,
83 M68K_REG_D4,
84 M68K_REG_D5,
85 M68K_REG_D6,
86 M68K_REG_D7,
87 M68K_REG_A0, /* Address registers */
88 M68K_REG_A1,
89 M68K_REG_A2,
90 M68K_REG_A3,
91 M68K_REG_A4,
92 M68K_REG_A5,
93 M68K_REG_A6,
94 M68K_REG_A7,
95 M68K_REG_PC, /* Program Counter */
96 M68K_REG_SR, /* Status Register */
97 M68K_REG_SP, /* The current Stack Pointer (located in A7) */
98 M68K_REG_USP, /* User Stack Pointer */
99 M68K_REG_ISP, /* Interrupt Stack Pointer */
100 M68K_REG_MSP, /* Master Stack Pointer */
101 M68K_REG_SFC, /* Source Function Code */
102 M68K_REG_DFC, /* Destination Function Code */
103 M68K_REG_VBR, /* Vector Base Register */
104 M68K_REG_CACR, /* Cache Control Register */
105 M68K_REG_CAAR, /* Cache Address Register */
107 /* Assumed registers */
108 /* These are cheat registers which emulate the 1-longword prefetch
109 * present in the 68000 and 68010.
110 */
111 M68K_REG_PREF_ADDR, /* Last prefetch address */
112 M68K_REG_PREF_DATA, /* Last prefetch data */
114 /* Convenience registers */
115 M68K_REG_PPC, /* Previous value in the program counter */
116 M68K_REG_IR, /* Instruction register */
117 M68K_REG_CPU_TYPE /* Type of CPU being run */
118 } m68k_register_t;
120 /* ======================================================================== */
121 /* ====================== FUNCTIONS CALLED BY THE CPU ===================== */
122 /* ======================================================================== */
124 /* You will have to implement these functions */
126 /* read/write functions called by the CPU to access memory.
127 * while values used are 32 bits, only the appropriate number
128 * of bits are relevant (i.e. in write_memory_8, only the lower 8 bits
129 * of value should be written to memory).
130 *
131 * NOTE: I have separated the immediate and PC-relative memory fetches
132 * from the other memory fetches because some systems require
133 * differentiation between PROGRAM and DATA fetches (usually
134 * for security setups such as encryption).
135 * This separation can either be achieved by setting
136 * M68K_SEPARATE_READS in m68kconf.h and defining
137 * the read functions, or by setting M68K_EMULATE_FC and
138 * making a function code callback function.
139 * Using the callback offers better emulation coverage
140 * because you can also monitor whether the CPU is in SYSTEM or
141 * USER mode, but it is also slower.
142 */
144 /* Read from anywhere */
145 unsigned int m68k_read_memory_8(unsigned int address);
146 unsigned int m68k_read_memory_16(unsigned int address);
147 unsigned int m68k_read_memory_32(unsigned int address);
149 /* Read data immediately following the PC */
150 unsigned int m68k_read_immediate_16(unsigned int address);
151 unsigned int m68k_read_immediate_32(unsigned int address);
153 /* Read data relative to the PC */
154 unsigned int m68k_read_pcrelative_8(unsigned int address);
155 unsigned int m68k_read_pcrelative_16(unsigned int address);
156 unsigned int m68k_read_pcrelative_32(unsigned int address);
158 /* Memory access for the disassembler */
159 unsigned int m68k_read_disassembler_8 (unsigned int address);
160 unsigned int m68k_read_disassembler_16 (unsigned int address);
161 unsigned int m68k_read_disassembler_32 (unsigned int address);
163 /* Write to anywhere */
164 void m68k_write_memory_8(unsigned int address, unsigned int value);
165 void m68k_write_memory_16(unsigned int address, unsigned int value);
166 void m68k_write_memory_32(unsigned int address, unsigned int value);
170 /* ======================================================================== */
171 /* ============================== CALLBACKS =============================== */
172 /* ======================================================================== */
174 /* These functions allow you to set callbacks to the host when specific events
175 * occur. Note that you must enable the corresponding value in m68kconf.h
176 * in order for these to do anything useful.
177 * Note: I have defined default callbacks which are used if you have enabled
178 * the corresponding #define in m68kconf.h but either haven't assigned a
179 * callback or have assigned a callback of NULL.
180 */
182 /* Set the callback for an interrupt acknowledge.
183 * You must enable M68K_EMULATE_INT_ACK in m68kconf.h.
184 * The CPU will call the callback with the interrupt level being acknowledged.
185 * The host program must return either a vector from 0x02-0xff, or one of the
186 * special interrupt acknowledge values specified earlier in this header.
187 * If this is not implemented, the CPU will always assume an autovectored
188 * interrupt, and will automatically clear the interrupt request when it
189 * services the interrupt.
190 * Default behavior: return M68K_INT_ACK_AUTOVECTOR.
191 */
192 void m68k_set_int_ack_callback(int (*callback)(int int_level));
195 /* Set the callback for a breakpoint acknowledge (68010+).
196 * You must enable M68K_EMULATE_BKPT_ACK in m68kconf.h.
197 * The CPU will call the callback with whatever was in the data field of the
198 * BKPT instruction for 68020+, or 0 for 68010.
199 * Default behavior: do nothing.
200 */
201 void m68k_set_bkpt_ack_callback(void (*callback)(unsigned int data));
204 /* Set the callback for the RESET instruction.
205 * You must enable M68K_EMULATE_RESET in m68kconf.h.
206 * The CPU calls this callback every time it encounters a RESET instruction.
207 * Default behavior: do nothing.
208 */
209 void m68k_set_reset_instr_callback(void (*callback)(void));
212 /* Set the callback for informing of a large PC change.
213 * You must enable M68K_MONITOR_PC in m68kconf.h.
214 * The CPU calls this callback with the new PC value every time the PC changes
215 * by a large value (currently set for changes by longwords).
216 * Default behavior: do nothing.
217 */
218 void m68k_set_pc_changed_callback(void (*callback)(unsigned int new_pc));
221 /* Set the callback for CPU function code changes.
222 * You must enable M68K_EMULATE_FC in m68kconf.h.
223 * The CPU calls this callback with the function code before every memory
224 * access to set the CPU's function code according to what kind of memory
225 * access it is (supervisor/user, program/data and such).
226 * Default behavior: do nothing.
227 */
228 void m68k_set_fc_callback(void (*callback)(unsigned int new_fc));
231 /* Set a callback for the instruction cycle of the CPU.
232 * You must enable M68K_INSTRUCTION_HOOK in m68kconf.h.
233 * The CPU calls this callback just before fetching the opcode in the
234 * instruction cycle.
235 * Default behavior: do nothing.
236 */
237 void m68k_set_instr_hook_callback(void (*callback)(void));
241 /* ======================================================================== */
242 /* ====================== FUNCTIONS TO ACCESS THE CPU ===================== */
243 /* ======================================================================== */
245 /* Use this function to set the CPU type you want to emulate.
246 * Currently supported types are: M68K_CPU_TYPE_68000, M68K_CPU_TYPE_68010,
247 * M68K_CPU_TYPE_EC020, and M68K_CPU_TYPE_68020.
248 */
249 void m68k_set_cpu_type(unsigned int cpu_type);
251 /* Pulse the RESET pin on the CPU.
252 * You *MUST* reset the CPU at least once to initialize the emulation
253 * Note: If you didn't call m68k_set_cpu_type() before resetting
254 * the CPU for the first time, the CPU will be set to
255 * M68K_CPU_TYPE_68000.
256 */
257 void m68k_pulse_reset(void);
259 /* execute num_cycles worth of instructions. returns number of cycles used */
260 int m68k_execute(int num_cycles);
262 /* These functions let you read/write/modify the number of cycles left to run
263 * while m68k_execute() is running.
264 * These are useful if the 68k accesses a memory-mapped port on another device
265 * that requires immediate processing by another CPU.
266 */
267 int m68k_cycles_run(void); /* Number of cycles run so far */
268 int m68k_cycles_remaining(void); /* Number of cycles left */
269 void m68k_modify_timeslice(int cycles); /* Modify cycles left */
270 void m68k_end_timeslice(void); /* End timeslice now */
272 /* Set the IPL0-IPL2 pins on the CPU (IRQ).
273 * A transition from < 7 to 7 will cause a non-maskable interrupt (NMI).
274 * Setting IRQ to 0 will clear an interrupt request.
275 */
276 void m68k_set_irq(unsigned int int_level);
279 /* Halt the CPU as if you pulsed the HALT pin. */
280 void m68k_pulse_halt(void);
283 /* Context switching to allow multiple CPUs */
285 /* Get the size of the cpu context in bytes */
286 unsigned int m68k_context_size(void);
288 /* Get a cpu context */
289 unsigned int m68k_get_context(void* dst);
291 /* set the current cpu context */
292 void m68k_set_context(void* dst);
294 /* Save the current cpu context to disk.
295 * You must provide a function pointer of the form:
296 * void save_value(char* identifier, unsigned int value)
297 */
298 void m68k_save_context( void (*save_value)(char* identifier, unsigned int value));
300 /* Load a cpu context from disk.
301 * You must provide a function pointer of the form:
302 * unsigned int load_value(char* identifier)
303 */
304 void m68k_load_context(unsigned int (*load_value)(char* identifier));
308 /* Peek at the internals of a CPU context. This can either be a context
309 * retrieved using m68k_get_context() or the currently running context.
310 * If context is NULL, the currently running CPU context will be used.
311 */
312 unsigned int m68k_get_reg(void* context, m68k_register_t reg);
314 /* Poke values into the internals of the currently running CPU context */
315 void m68k_set_reg(m68k_register_t reg, unsigned int value);
317 /* Check if an instruction is valid for the specified CPU type */
318 unsigned int m68k_is_valid_instruction(unsigned int instruction, unsigned int cpu_type);
320 /* Disassemble 1 instruction using the epecified CPU type at pc. Stores
321 * disassembly in str_buff and returns the size of the instruction in bytes.
322 */
323 unsigned int m68k_disassemble(char* str_buff, unsigned int pc, unsigned int cpu_type);
326 /* ======================================================================== */
327 /* ============================= CONFIGURATION ============================ */
328 /* ======================================================================== */
330 /* Import the configuration for this build */
331 #include "m68kconf.h"
335 /* ======================================================================== */
336 /* ============================== END OF FILE ============================= */
337 /* ======================================================================== */
339 #endif /* M68K__HEADER */