/* m6811_cpu.c -- 68HC11&68HC12 CPU Emulation
Copyright 1999-2016 Free Software Foundation, Inc.
Written by Stephane Carrez (stcarrez@nerim.fr)
This file is part of GDB, GAS, and the GNU binutils.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see . */
#include "sim-main.h"
#include "sim-assert.h"
#include "sim-module.h"
#include "sim-options.h"
enum {
OPTION_CPU_RESET = OPTION_START,
OPTION_EMUL_OS,
OPTION_CPU_CONFIG,
OPTION_CPU_BOOTSTRAP,
OPTION_CPU_MODE
};
static DECLARE_OPTION_HANDLER (cpu_option_handler);
static const OPTION cpu_options[] =
{
{ {"cpu-reset", no_argument, NULL, OPTION_CPU_RESET },
'\0', NULL, "Reset the CPU",
cpu_option_handler },
{ {"emulos", no_argument, NULL, OPTION_EMUL_OS },
'\0', NULL, "Emulate some OS system calls (read, write, ...)",
cpu_option_handler },
{ {"cpu-config", required_argument, NULL, OPTION_CPU_CONFIG },
'\0', NULL, "Specify the initial CPU configuration register",
cpu_option_handler },
{ {"bootstrap", no_argument, NULL, OPTION_CPU_BOOTSTRAP },
'\0', NULL, "Start the processing in bootstrap mode",
cpu_option_handler },
{ {NULL, no_argument, NULL, 0}, '\0', NULL, NULL, NULL }
};
static SIM_RC
cpu_option_handler (SIM_DESC sd, sim_cpu *cpu,
int opt, char *arg, int is_command)
{
int val;
cpu = STATE_CPU (sd, 0);
switch (opt)
{
case OPTION_CPU_RESET:
sim_board_reset (sd);
break;
case OPTION_EMUL_OS:
cpu->cpu_emul_syscall = 1;
break;
case OPTION_CPU_CONFIG:
if (sscanf(arg, "0x%x", &val) == 1
|| sscanf(arg, "%d", &val) == 1)
{
cpu->cpu_config = val;
cpu->cpu_use_local_config = 1;
}
else
cpu->cpu_use_local_config = 0;
break;
case OPTION_CPU_BOOTSTRAP:
cpu->cpu_start_mode = "bootstrap";
break;
case OPTION_CPU_MODE:
break;
}
return SIM_RC_OK;
}
void
cpu_call (sim_cpu *cpu, uint16 addr)
{
cpu_set_pc (cpu, addr);
}
void
cpu_return (sim_cpu *cpu)
{
}
/* Set the stack pointer and re-compute the current frame. */
void
cpu_set_sp (sim_cpu *cpu, uint16 val)
{
cpu->cpu_regs.sp = val;
}
uint16
cpu_get_reg (sim_cpu *cpu, uint8 reg)
{
switch (reg)
{
case 0:
return cpu_get_x (cpu);
case 1:
return cpu_get_y (cpu);
case 2:
return cpu_get_sp (cpu);
case 3:
return cpu_get_pc (cpu);
default:
return 0;
}
}
uint16
cpu_get_src_reg (sim_cpu *cpu, uint8 reg)
{
switch (reg)
{
case 0:
return cpu_get_a (cpu);
case 1:
return cpu_get_b (cpu);
case 2:
return cpu_get_ccr (cpu);
case 3:
return cpu_get_tmp3 (cpu);
case 4:
return cpu_get_d (cpu);
case 5:
return cpu_get_x (cpu);
case 6:
return cpu_get_y (cpu);
case 7:
return cpu_get_sp (cpu);
default:
return 0;
}
}
void
cpu_set_dst_reg (sim_cpu *cpu, uint8 reg, uint16 val)
{
switch (reg)
{
case 0:
cpu_set_a (cpu, val);
break;
case 1:
cpu_set_b (cpu, val);
break;
case 2:
cpu_set_ccr (cpu, val);
break;
case 3:
cpu_set_tmp2 (cpu, val);
break;
case 4:
cpu_set_d (cpu, val);
break;
case 5:
cpu_set_x (cpu, val);
break;
case 6:
cpu_set_y (cpu, val);
break;
case 7:
cpu_set_sp (cpu, val);
break;
default:
break;
}
}
void
cpu_set_reg (sim_cpu *cpu, uint8 reg, uint16 val)
{
switch (reg)
{
case 0:
cpu_set_x (cpu, val);
break;
case 1:
cpu_set_y (cpu, val);
break;
case 2:
cpu_set_sp (cpu, val);
break;
case 3:
cpu_set_pc (cpu, val);
break;
default:
break;
}
}
/* Returns the address of a 68HC12 indexed operand.
Pre and post modifications are handled on the source register. */
uint16
cpu_get_indexed_operand_addr (sim_cpu *cpu, int restricted)
{
uint8 reg;
uint16 sval;
uint16 addr;
uint8 code;
code = cpu_fetch8 (cpu);
/* n,r with 5-bit signed constant. */
if ((code & 0x20) == 0)
{
reg = (code >> 6) & 3;
sval = (code & 0x1f);
if (code & 0x10)
sval |= 0xfff0;
addr = cpu_get_reg (cpu, reg);
addr += sval;
}
/* Auto pre/post increment/decrement. */
else if ((code & 0xc0) != 0xc0)
{
reg = (code >> 6) & 3;
sval = (code & 0x0f);
if (sval & 0x8)
{
sval |= 0xfff0;
}
else
{
sval = sval + 1;
}
addr = cpu_get_reg (cpu, reg);
cpu_set_reg (cpu, reg, addr + sval);
if ((code & 0x10) == 0)
{
addr += sval;
}
}
/* [n,r] 16-bits offset indexed indirect. */
else if ((code & 0x07) == 3)
{
if (restricted)
{
return 0;
}
reg = (code >> 3) & 0x03;
addr = cpu_get_reg (cpu, reg);
addr += cpu_fetch16 (cpu);
addr = memory_read16 (cpu, addr);
cpu_add_cycles (cpu, 1);
}
else if ((code & 0x4) == 0)
{
if (restricted)
{
return 0;
}
reg = (code >> 3) & 0x03;
addr = cpu_get_reg (cpu, reg);
if (code & 0x2)
{
sval = cpu_fetch16 (cpu);
cpu_add_cycles (cpu, 1);
}
else
{
sval = cpu_fetch8 (cpu);
if (code & 0x1)
sval |= 0xff00;
cpu_add_cycles (cpu, 1);
}
addr += sval;
}
else
{
reg = (code >> 3) & 0x03;
addr = cpu_get_reg (cpu, reg);
switch (code & 3)
{
case 0:
addr += cpu_get_a (cpu);
break;
case 1:
addr += cpu_get_b (cpu);
break;
case 2:
addr += cpu_get_d (cpu);
break;
case 3:
default:
addr += cpu_get_d (cpu);
addr = memory_read16 (cpu, addr);
cpu_add_cycles (cpu, 1);
break;
}
}
return addr;
}
uint8
cpu_get_indexed_operand8 (sim_cpu *cpu, int restricted)
{
uint16 addr;
addr = cpu_get_indexed_operand_addr (cpu, restricted);
return memory_read8 (cpu, addr);
}
uint16
cpu_get_indexed_operand16 (sim_cpu *cpu, int restricted)
{
uint16 addr;
addr = cpu_get_indexed_operand_addr (cpu, restricted);
return memory_read16 (cpu, addr);
}
void
cpu_move8 (sim_cpu *cpu, uint8 code)
{
uint8 src;
uint16 addr;
switch (code)
{
case 0x0b:
src = cpu_fetch8 (cpu);
addr = cpu_fetch16 (cpu);
break;
case 0x08:
addr = cpu_get_indexed_operand_addr (cpu, 1);
src = cpu_fetch8 (cpu);
break;
case 0x0c:
addr = cpu_fetch16 (cpu);
src = memory_read8 (cpu, addr);
addr = cpu_fetch16 (cpu);
break;
case 0x09:
addr = cpu_get_indexed_operand_addr (cpu, 1);
src = memory_read8 (cpu, cpu_fetch16 (cpu));
break;
case 0x0d:
src = cpu_get_indexed_operand8 (cpu, 1);
addr = cpu_fetch16 (cpu);
break;
case 0x0a:
src = cpu_get_indexed_operand8 (cpu, 1);
addr = cpu_get_indexed_operand_addr (cpu, 1);
break;
default:
sim_engine_abort (CPU_STATE (cpu), cpu, 0,
"Invalid code 0x%0x -- internal error?", code);
return;
}
memory_write8 (cpu, addr, src);
}
void
cpu_move16 (sim_cpu *cpu, uint8 code)
{
uint16 src;
uint16 addr;
switch (code)
{
case 0x03:
src = cpu_fetch16 (cpu);
addr = cpu_fetch16 (cpu);
break;
case 0x00:
addr = cpu_get_indexed_operand_addr (cpu, 1);
src = cpu_fetch16 (cpu);
break;
case 0x04:
addr = cpu_fetch16 (cpu);
src = memory_read16 (cpu, addr);
addr = cpu_fetch16 (cpu);
break;
case 0x01:
addr = cpu_get_indexed_operand_addr (cpu, 1);
src = memory_read16 (cpu, cpu_fetch16 (cpu));
break;
case 0x05:
src = cpu_get_indexed_operand16 (cpu, 1);
addr = cpu_fetch16 (cpu);
break;
case 0x02:
src = cpu_get_indexed_operand16 (cpu, 1);
addr = cpu_get_indexed_operand_addr (cpu, 1);
break;
default:
sim_engine_abort (CPU_STATE (cpu), cpu, 0,
"Invalid code 0x%0x -- internal error?", code);
return;
}
memory_write16 (cpu, addr, src);
}
int
cpu_initialize (SIM_DESC sd, sim_cpu *cpu)
{
sim_add_option_table (sd, 0, cpu_options);
memset (&cpu->cpu_regs, 0, sizeof(cpu->cpu_regs));
cpu->cpu_absolute_cycle = 0;
cpu->cpu_current_cycle = 0;
cpu->cpu_emul_syscall = 1;
cpu->cpu_running = 1;
cpu->cpu_stop_on_interrupt = 0;
cpu->cpu_frequency = 8 * 1000 * 1000;
cpu->cpu_use_elf_start = 0;
cpu->cpu_elf_start = 0;
cpu->cpu_use_local_config = 0;
cpu->bank_start = 0;
cpu->bank_end = 0;
cpu->bank_shift = 0;
cpu->cpu_config = M6811_NOSEC | M6811_NOCOP | M6811_ROMON |
M6811_EEON;
interrupts_initialize (sd, cpu);
cpu->cpu_is_initialized = 1;
return 0;
}
/* Reinitialize the processor after a reset. */
int
cpu_reset (sim_cpu *cpu)
{
/* Initialize the config register.
It is only initialized at reset time. */
memset (cpu->ios, 0, sizeof (cpu->ios));
if (cpu->cpu_configured_arch->arch == bfd_arch_m68hc11)
cpu->ios[M6811_INIT] = 0x1;
else
cpu->ios[M6811_INIT] = 0;
/* Output compare registers set to 0xFFFF. */
cpu->ios[M6811_TOC1_H] = 0xFF;
cpu->ios[M6811_TOC1_L] = 0xFF;
cpu->ios[M6811_TOC2_H] = 0xFF;
cpu->ios[M6811_TOC2_L] = 0xFF;
cpu->ios[M6811_TOC3_H] = 0xFF;
cpu->ios[M6811_TOC4_L] = 0xFF;
cpu->ios[M6811_TOC5_H] = 0xFF;
cpu->ios[M6811_TOC5_L] = 0xFF;
/* Setup the processor registers. */
memset (&cpu->cpu_regs, 0, sizeof(cpu->cpu_regs));
cpu->cpu_absolute_cycle = 0;
cpu->cpu_current_cycle = 0;
cpu->cpu_is_initialized = 0;
/* Reset interrupts. */
interrupts_reset (&cpu->cpu_interrupts);
/* Reinitialize the CPU operating mode. */
cpu->ios[M6811_HPRIO] = cpu->cpu_mode;
return 0;
}
/* Reinitialize the processor after a reset. */
int
cpu_restart (sim_cpu *cpu)
{
uint16 addr;
/* Get CPU starting address depending on the CPU mode. */
if (cpu->cpu_use_elf_start == 0)
{
switch ((cpu->ios[M6811_HPRIO]) & (M6811_SMOD | M6811_MDA))
{
/* Single Chip */
default:
case 0 :
addr = memory_read16 (cpu, 0xFFFE);
break;
/* Expanded Multiplexed */
case M6811_MDA:
addr = memory_read16 (cpu, 0xFFFE);
break;
/* Special Bootstrap */
case M6811_SMOD:
addr = 0;
break;
/* Factory Test */
case M6811_MDA | M6811_SMOD:
addr = memory_read16 (cpu, 0xFFFE);
break;
}
}
else
{
addr = cpu->cpu_elf_start;
}
/* Setup the processor registers. */
cpu->cpu_insn_pc = addr;
cpu->cpu_regs.pc = addr;
cpu->cpu_regs.ccr = M6811_X_BIT | M6811_I_BIT | M6811_S_BIT;
cpu->cpu_absolute_cycle = 0;
cpu->cpu_is_initialized = 1;
cpu->cpu_current_cycle = 0;
cpu_call (cpu, addr);
return 0;
}
void
print_io_reg_desc (SIM_DESC sd, io_reg_desc *desc, int val, int mode)
{
while (desc->mask)
{
if (val & desc->mask)
sim_io_printf (sd, "%s",
mode == 0 ? desc->short_name : desc->long_name);
desc++;
}
}
void
print_io_byte (SIM_DESC sd, const char *name, io_reg_desc *desc,
uint8 val, uint16 addr)
{
sim_io_printf (sd, " %-9.9s @ 0x%04x 0x%02x ", name, addr, val);
if (desc)
print_io_reg_desc (sd, desc, val, 0);
}
void
print_io_word (SIM_DESC sd, const char *name, io_reg_desc *desc,
uint16 val, uint16 addr)
{
sim_io_printf (sd, " %-9.9s @ 0x%04x 0x%04x ", name, addr, val);
if (desc)
print_io_reg_desc (sd, desc, val, 0);
}
void
cpu_ccr_update_tst8 (sim_cpu *cpu, uint8 val)
{
cpu_set_ccr_V (cpu, 0);
cpu_set_ccr_N (cpu, val & 0x80 ? 1 : 0);
cpu_set_ccr_Z (cpu, val == 0 ? 1 : 0);
}
uint16
cpu_fetch_relbranch (sim_cpu *cpu)
{
uint16 addr = (uint16) cpu_fetch8 (cpu);
if (addr & 0x0080)
{
addr |= 0xFF00;
}
addr += cpu->cpu_regs.pc;
return addr;
}
uint16
cpu_fetch_relbranch16 (sim_cpu *cpu)
{
uint16 addr = cpu_fetch16 (cpu);
addr += cpu->cpu_regs.pc;
return addr;
}
/* Push all the CPU registers (when an interruption occurs). */
void
cpu_push_all (sim_cpu *cpu)
{
if (cpu->cpu_configured_arch->arch == bfd_arch_m68hc11)
{
cpu_m68hc11_push_uint16 (cpu, cpu->cpu_regs.pc);
cpu_m68hc11_push_uint16 (cpu, cpu->cpu_regs.iy);
cpu_m68hc11_push_uint16 (cpu, cpu->cpu_regs.ix);
cpu_m68hc11_push_uint16 (cpu, cpu->cpu_regs.d);
cpu_m68hc11_push_uint8 (cpu, cpu->cpu_regs.ccr);
}
else
{
cpu_m68hc12_push_uint16 (cpu, cpu->cpu_regs.pc);
cpu_m68hc12_push_uint16 (cpu, cpu->cpu_regs.iy);
cpu_m68hc12_push_uint16 (cpu, cpu->cpu_regs.ix);
cpu_m68hc12_push_uint16 (cpu, cpu->cpu_regs.d);
cpu_m68hc12_push_uint8 (cpu, cpu->cpu_regs.ccr);
}
}
/* Simulation of the dbcc/ibcc/tbcc 68HC12 conditional branch operations. */
void
cpu_dbcc (sim_cpu *cpu)
{
uint8 code;
uint16 addr;
uint16 inc;
uint16 reg;
code = cpu_fetch8 (cpu);
switch (code & 0xc0)
{
case 0x80: /* ibcc */
inc = 1;
break;
case 0x40: /* tbcc */
inc = 0;
break;
case 0: /* dbcc */
inc = -1;
break;
default:
abort ();
break;
}
addr = cpu_fetch8 (cpu);
if (code & 0x10)
addr |= 0xff00;
addr += cpu_get_pc (cpu);
reg = cpu_get_src_reg (cpu, code & 0x07);
reg += inc;
/* Branch according to register value. */
if ((reg != 0 && (code & 0x20)) || (reg == 0 && !(code & 0x20)))
{
cpu_set_pc (cpu, addr);
}
cpu_set_dst_reg (cpu, code & 0x07, reg);
}
void
cpu_exg (sim_cpu *cpu, uint8 code)
{
uint8 r1, r2;
uint16 src1;
uint16 src2;
r1 = (code >> 4) & 0x07;
r2 = code & 0x07;
if (code & 0x80)
{
src1 = cpu_get_src_reg (cpu, r1);
src2 = cpu_get_src_reg (cpu, r2);
if (r2 == 1 || r2 == 2)
src2 |= 0xff00;
cpu_set_dst_reg (cpu, r2, src1);
cpu_set_dst_reg (cpu, r1, src2);
}
else
{
src1 = cpu_get_src_reg (cpu, r1);
/* Sign extend the 8-bit registers (A, B, CCR). */
if ((r1 == 0 || r1 == 1 || r1 == 2) && (src1 & 0x80))
src1 |= 0xff00;
cpu_set_dst_reg (cpu, r2, src1);
}
}
/* Handle special instructions. */
void
cpu_special (sim_cpu *cpu, enum M6811_Special special)
{
switch (special)
{
case M6811_RTI:
{
uint8 ccr;
ccr = cpu_m68hc11_pop_uint8 (cpu);
cpu_set_ccr (cpu, ccr);
cpu_set_d (cpu, cpu_m68hc11_pop_uint16 (cpu));
cpu_set_x (cpu, cpu_m68hc11_pop_uint16 (cpu));
cpu_set_y (cpu, cpu_m68hc11_pop_uint16 (cpu));
cpu_set_pc (cpu, cpu_m68hc11_pop_uint16 (cpu));
cpu_return (cpu);
break;
}
case M6812_RTI:
{
uint8 ccr;
ccr = cpu_m68hc12_pop_uint8 (cpu);
cpu_set_ccr (cpu, ccr);
cpu_set_d (cpu, cpu_m68hc12_pop_uint16 (cpu));
cpu_set_x (cpu, cpu_m68hc12_pop_uint16 (cpu));
cpu_set_y (cpu, cpu_m68hc12_pop_uint16 (cpu));
cpu_set_pc (cpu, cpu_m68hc12_pop_uint16 (cpu));
cpu_return (cpu);
break;
}
case M6811_WAI:
/* In the ELF-start mode, we are in a special mode where
the WAI corresponds to an exit. */
if (cpu->cpu_use_elf_start)
{
cpu_set_pc (cpu, cpu->cpu_insn_pc);
sim_engine_halt (CPU_STATE (cpu), cpu,
NULL, NULL_CIA, sim_exited,
cpu_get_d (cpu));
return;
}
/* SCz: not correct... */
cpu_push_all (cpu);
break;
case M6811_SWI:
interrupts_raise (&cpu->cpu_interrupts, M6811_INT_SWI);
interrupts_process (&cpu->cpu_interrupts);
break;
case M6811_EMUL_SYSCALL:
case M6811_ILLEGAL:
if (cpu->cpu_emul_syscall)
{
uint8 op = memory_read8 (cpu,
cpu_get_pc (cpu) - 1);
if (op == 0x41)
{
cpu_set_pc (cpu, cpu->cpu_insn_pc);
sim_engine_halt (CPU_STATE (cpu), cpu,
NULL, NULL_CIA, sim_exited,
cpu_get_d (cpu));
return;
}
else
{
emul_os (op, cpu);
}
return;
}
interrupts_raise (&cpu->cpu_interrupts, M6811_INT_ILLEGAL);
interrupts_process (&cpu->cpu_interrupts);
break;
case M6811_TEST:
case M6812_BGND:
{
SIM_DESC sd;
sd = CPU_STATE (cpu);
/* Breakpoint instruction if we are under gdb. */
if (STATE_OPEN_KIND (sd) == SIM_OPEN_DEBUG)
{
cpu->cpu_regs.pc --;
sim_engine_halt (CPU_STATE (cpu), cpu,
0, cpu_get_pc (cpu), sim_stopped,
SIM_SIGTRAP);
}
/* else this is a nop but not in test factory mode. */
break;
}
case M6812_IDIVS:
{
int32 src1 = (int16) cpu_get_d (cpu);
int32 src2 = (int16) cpu_get_x (cpu);
if (src2 == 0)
{
cpu_set_ccr_C (cpu, 1);
}
else
{
cpu_set_d (cpu, src1 % src2);
src1 = src1 / src2;
cpu_set_x (cpu, src1);
cpu_set_ccr_C (cpu, 0);
cpu_set_ccr_Z (cpu, src1 == 0);
cpu_set_ccr_N (cpu, src1 & 0x8000);
cpu_set_ccr_V (cpu, src1 >= 32768 || src1 < -32768);
}
}
break;
case M6812_EDIV:
{
uint32 src1 = (uint32) cpu_get_x (cpu);
uint32 src2 = (uint32) (cpu_get_y (cpu) << 16)
| (uint32) (cpu_get_d (cpu));
if (src1 == 0)
{
cpu_set_ccr_C (cpu, 1);
}
else
{
cpu_set_ccr_C (cpu, 0);
cpu_set_d (cpu, src2 % src1);
src2 = src2 / src1;
cpu_set_y (cpu, src2);
cpu_set_ccr_Z (cpu, src2 == 0);
cpu_set_ccr_N (cpu, (src2 & 0x8000) != 0);
cpu_set_ccr_V (cpu, (src2 & 0xffff0000) != 0);
}
}
break;
case M6812_EDIVS:
{
int32 src1 = (int16) cpu_get_x (cpu);
int32 src2 = (uint32) (cpu_get_y (cpu) << 16)
| (uint32) (cpu_get_d (cpu));
if (src1 == 0)
{
cpu_set_ccr_C (cpu, 1);
}
else
{
cpu_set_ccr_C (cpu, 0);
cpu_set_d (cpu, src2 % src1);
src2 = src2 / src1;
cpu_set_y (cpu, src2);
cpu_set_ccr_Z (cpu, src2 == 0);
cpu_set_ccr_N (cpu, (src2 & 0x8000) != 0);
cpu_set_ccr_V (cpu, src2 > 32767 || src2 < -32768);
}
}
break;
case M6812_EMULS:
{
int32 src1, src2;
src1 = (int16) cpu_get_d (cpu);
src2 = (int16) cpu_get_y (cpu);
src1 = src1 * src2;
cpu_set_d (cpu, src1 & 0x0ffff);
cpu_set_y (cpu, src1 >> 16);
cpu_set_ccr_Z (cpu, src1 == 0);
cpu_set_ccr_N (cpu, (src1 & 0x80000000) != 0);
cpu_set_ccr_C (cpu, (src1 & 0x00008000) != 0);
}
break;
case M6812_EMACS:
{
int32 src1, src2;
uint16 addr;
addr = cpu_fetch16 (cpu);
src1 = (int16) memory_read16 (cpu, cpu_get_x (cpu));
src2 = (int16) memory_read16 (cpu, cpu_get_y (cpu));
src1 = src1 * src2;
src2 = (((uint32) memory_read16 (cpu, addr)) << 16)
| (uint32) memory_read16 (cpu, addr + 2);
memory_write16 (cpu, addr, (src1 + src2) >> 16);
memory_write16 (cpu, addr + 2, (src1 + src2));
}
break;
case M6812_CALL:
{
uint8 page;
uint16 addr;
addr = cpu_fetch16 (cpu);
page = cpu_fetch8 (cpu);
cpu_m68hc12_push_uint16 (cpu, cpu_get_pc (cpu));
cpu_m68hc12_push_uint8 (cpu, cpu_get_page (cpu));
cpu_set_page (cpu, page);
cpu_set_pc (cpu, addr);
}
break;
case M6812_CALL_INDIRECT:
{
uint8 code;
uint16 addr;
uint8 page;
code = memory_read8 (cpu, cpu_get_pc (cpu));
/* Indirect addressing call has the page specified in the
memory location pointed to by the address. */
if ((code & 0xE3) == 0xE3)
{
addr = cpu_get_indexed_operand_addr (cpu, 0);
page = memory_read8 (cpu, addr + 2);
addr = memory_read16 (cpu, addr);
}
else
{
/* Otherwise, page is in the opcode. */
addr = cpu_get_indexed_operand16 (cpu, 0);
page = cpu_fetch8 (cpu);
}
cpu_m68hc12_push_uint16 (cpu, cpu_get_pc (cpu));
cpu_m68hc12_push_uint8 (cpu, cpu_get_page (cpu));
cpu_set_page (cpu, page);
cpu_set_pc (cpu, addr);
}
break;
case M6812_RTC:
{
uint8 page = cpu_m68hc12_pop_uint8 (cpu);
uint16 addr = cpu_m68hc12_pop_uint16 (cpu);
cpu_set_page (cpu, page);
cpu_set_pc (cpu, addr);
}
break;
case M6812_ETBL:
default:
sim_engine_halt (CPU_STATE (cpu), cpu, NULL,
cpu_get_pc (cpu), sim_stopped,
SIM_SIGILL);
break;
}
}
void
cpu_single_step (sim_cpu *cpu)
{
cpu->cpu_current_cycle = 0;
cpu->cpu_insn_pc = cpu_get_pc (cpu);
/* Handle the pending interrupts. If an interrupt is handled,
treat this as an single step. */
if (interrupts_process (&cpu->cpu_interrupts))
{
cpu->cpu_absolute_cycle += cpu->cpu_current_cycle;
return;
}
/* printf("PC = 0x%04x\n", cpu_get_pc (cpu));*/
cpu->cpu_interpretor (cpu);
cpu->cpu_absolute_cycle += cpu->cpu_current_cycle;
}
/* VARARGS */
void
sim_memory_error (sim_cpu *cpu, SIM_SIGNAL excep,
uint16 addr, const char *message, ...)
{
char buf[1024];
va_list args;
va_start (args, message);
vsprintf (buf, message, args);
va_end (args);
sim_io_printf (CPU_STATE (cpu), "%s\n", buf);
cpu_memory_exception (cpu, excep, addr, buf);
}
void
cpu_memory_exception (sim_cpu *cpu, SIM_SIGNAL excep,
uint16 addr, const char *message)
{
if (cpu->cpu_running == 0)
return;
cpu_set_pc (cpu, cpu->cpu_insn_pc);
sim_engine_halt (CPU_STATE (cpu), cpu, NULL,
cpu_get_pc (cpu), sim_stopped, excep);
#if 0
cpu->mem_exception = excep;
cpu->fault_addr = addr;
cpu->fault_msg = strdup (message);
if (cpu->cpu_use_handler)
{
longjmp (&cpu->cpu_exception_handler, 1);
}
(* cpu->callback->printf_filtered)
(cpu->callback, "Fault at 0x%04x: %s\n", addr, message);
#endif
}
void
cpu_info (SIM_DESC sd, sim_cpu *cpu)
{
sim_io_printf (sd, "CPU info:\n");
sim_io_printf (sd, " Absolute cycle: %s\n",
cycle_to_string (cpu, cpu->cpu_absolute_cycle,
PRINT_TIME | PRINT_CYCLE));
sim_io_printf (sd, " Syscall emulation: %s\n",
cpu->cpu_emul_syscall ? "yes, via 0xcd " : "no");
sim_io_printf (sd, " Memory errors detection: %s\n",
cpu->cpu_check_memory ? "yes" : "no");
sim_io_printf (sd, " Stop on interrupt: %s\n",
cpu->cpu_stop_on_interrupt ? "yes" : "no");
}