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// license:BSD-3-Clause
// copyright-holders:Olivier Galibert
#include "emu.h"
#include "m68000.h"
#include "m68kdasm.h"
DEFINE_DEVICE_TYPE(M68000, m68000_device, "m68000", "Motorola MC68000")
std::unique_ptr<util::disasm_interface> m68000_device::create_disassembler()
{
return std::make_unique<m68k_disassembler>(m68k_disassembler::TYPE_68000);
}
m68000_device::m68000_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock) : m68000_device(mconfig, M68000, tag, owner, clock)
{
}
m68000_device::m68000_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, u32 clock)
: m68000_base_device(mconfig, type, tag, owner, clock),
m_cmpild_instr_callback(*this),
m_rte_instr_callback(*this),
m_tas_write_callback(*this),
m_program_config("program", ENDIANNESS_BIG, 16, 24),
m_opcodes_config("opcodes", ENDIANNESS_BIG, 16, 24),
m_uprogram_config("uprogram", ENDIANNESS_BIG, 16, 24),
m_uopcodes_config("uopcodes", ENDIANNESS_BIG, 16, 24),
m_cpu_space_config("cpu_space", ENDIANNESS_BIG, 16, 24, 0, address_map_constructor(FUNC(m68000_device::default_autovectors_map), this)),
m_mmu(nullptr),
m_disable_spaces(false),
m_disable_specifics(false),
m_disable_interrupt_callback(false)
{
}
void m68000_device::set_current_mmu(mmu *mmu)
{
m_mmu = mmu;
if(m_mmu)
m_mmu->set_super(m_sr & SR_S);
}
void m68000_device::abort_access(u32 reason)
{
m_post_run = reason;
m_post_run_cycles = m_icount;
m_icount = 0;
}
void m68000_device::do_post_run()
{
m_icount = m_post_run_cycles;
m_post_run_cycles = 0;
switch(m_post_run) {
case PR_BERR:
m_inst_state = S_BUS_ERROR;
m_inst_substate = 0;
m_icount -= 10;
break;
}
m_post_run = 0;
}
u64 m68000_device::vpa_sync(offs_t, u64 current_time)
{
if(m_last_vpa_time >= current_time)
return m_last_vpa_time;
u64 mod = current_time % 10;
if(mod < 7)
m_last_vpa_time = current_time - mod + 10;
else
m_last_vpa_time = current_time - mod + 20;
return m_last_vpa_time;
}
u32 m68000_device::vpa_after(offs_t)
{
return 1;
}
void m68000_device::trigger_bus_error()
{
abort_access(PR_BERR);
}
void m68000_device::berr_w(u16)
{
trigger_bus_error();
}
u16 m68000_device::berr_r()
{
if(!machine().side_effects_disabled())
trigger_bus_error();
return 0;
}
bool m68000_device::supervisor_mode() const noexcept
{
return m_sr & SR_S;
}
u16 m68000_device::get_fc() const noexcept
{
return (m_base_ssw | (m_sr & SR_S ? SSW_S : 0)) & 7;
}
void m68000_device::execute_run()
{
m_icount -= m_count_before_instruction_step;
if(m_icount < 0) {
m_count_before_instruction_step = -m_icount;
m_icount = 0;
} else
m_count_before_instruction_step = 0;
for(;;) {
if(m_icount > 0 && m_inst_substate)
(this->*(m_handlers_p[m_inst_state]))();
while(m_icount > 0) {
if(m_inst_state >= S_first_instruction) {
m_ipc = m_pc - 2;
m_irdi = m_ird;
if(debugger_enabled())
debugger_instruction_hook(m_ipc);
}
(this->*(m_handlers_f[m_inst_state]))();
}
if(m_post_run)
do_post_run();
else
break;
}
if(m_icount < 0) {
m_count_before_instruction_step = -m_icount;
m_icount = 0;
}
}
device_memory_interface::space_config_vector m68000_device::memory_space_config() const
{
device_memory_interface::space_config_vector scv;
scv.push_back(std::make_pair(AS_PROGRAM, &m_program_config));
if(has_configured_map(AS_OPCODES))
scv.push_back(std::make_pair(AS_OPCODES, &m_opcodes_config));
if(has_configured_map(AS_USER_PROGRAM))
scv.push_back(std::make_pair(AS_USER_PROGRAM, &m_uprogram_config));
if(has_configured_map(AS_USER_OPCODES))
scv.push_back(std::make_pair(AS_USER_OPCODES, &m_opcodes_config));
if(m_cpu_space_id == AS_CPU_SPACE)
scv.push_back(std::make_pair(AS_CPU_SPACE, &m_cpu_space_config));
return scv;
}
void m68000_device::default_autovectors_map(address_map &map)
{
if(m_cpu_space_id == AS_CPU_SPACE && !has_configured_map(AS_CPU_SPACE)) {
offs_t mask = make_bitmask<offs_t>(m_cpu_space_config.m_addr_width) - 0xf;
map(mask + 0x3, mask + 0x3).before_time(*this, FUNC(m68000_device::vpa_sync)).after_delay(*this, FUNC(m68000_device::vpa_after)).lr8(NAME([] () -> u8 { return autovector(1); }));
map(mask + 0x5, mask + 0x5).before_time(*this, FUNC(m68000_device::vpa_sync)).after_delay(*this, FUNC(m68000_device::vpa_after)).lr8(NAME([] () -> u8 { return autovector(2); }));
map(mask + 0x7, mask + 0x7).before_time(*this, FUNC(m68000_device::vpa_sync)).after_delay(*this, FUNC(m68000_device::vpa_after)).lr8(NAME([] () -> u8 { return autovector(3); }));
map(mask + 0x9, mask + 0x9).before_time(*this, FUNC(m68000_device::vpa_sync)).after_delay(*this, FUNC(m68000_device::vpa_after)).lr8(NAME([] () -> u8 { return autovector(4); }));
map(mask + 0xb, mask + 0xb).before_time(*this, FUNC(m68000_device::vpa_sync)).after_delay(*this, FUNC(m68000_device::vpa_after)).lr8(NAME([] () -> u8 { return autovector(5); }));
map(mask + 0xd, mask + 0xd).before_time(*this, FUNC(m68000_device::vpa_sync)).after_delay(*this, FUNC(m68000_device::vpa_after)).lr8(NAME([] () -> u8 { return autovector(6); }));
map(mask + 0xf, mask + 0xf).before_time(*this, FUNC(m68000_device::vpa_sync)).after_delay(*this, FUNC(m68000_device::vpa_after)).lr8(NAME([] () -> u8 { return autovector(7); }));
}
}
void m68000_device::device_start()
{
init_decode_table();
m_cmpild_instr_callback.resolve();
m_rte_instr_callback.resolve();
m_tas_write_callback.resolve();
if(!m_disable_spaces) {
m_s_program = &space(AS_PROGRAM);
m_s_opcodes = has_space(AS_OPCODES) ? &space(AS_OPCODES) : m_s_program;
m_s_uprogram = has_space(AS_USER_PROGRAM) ? &space(AS_USER_PROGRAM) : m_s_program;
m_s_uopcodes = has_space(AS_USER_OPCODES) ? &space(AS_USER_OPCODES) : has_space(AS_USER_PROGRAM) ? m_s_uprogram : m_s_opcodes;
m_s_cpu_space = &space(m_cpu_space_id);
}
if(!(m_disable_specifics || m_disable_spaces)) {
m_s_program->specific(m_r_program);
m_s_opcodes->specific(m_r_opcodes);
m_s_uprogram->specific(m_r_uprogram);
m_s_uopcodes->specific(m_r_uopcodes);
m_s_cpu_space->specific(m_cpu_space);
}
if(m_mmu) {
m_handlers_f = s_handlers_if;
m_handlers_p = s_handlers_ip;
} else {
m_handlers_f = s_handlers_df;
m_handlers_p = s_handlers_dp;
}
save_item(NAME(m_da));
save_item(NAME(m_ipc));
save_item(NAME(m_pc));
save_item(NAME(m_au));
save_item(NAME(m_at));
save_item(NAME(m_aob));
save_item(NAME(m_dt));
save_item(NAME(m_int_vector));
save_item(NAME(m_sp));
save_item(NAME(m_bcount));
save_item(NAME(m_count_before_instruction_step));
save_item(NAME(m_t));
save_item(NAME(m_movems));
save_item(NAME(m_isr));
save_item(NAME(m_sr));
save_item(NAME(m_new_sr));
save_item(NAME(m_dbin));
save_item(NAME(m_dbout));
save_item(NAME(m_edb));
save_item(NAME(m_irc));
save_item(NAME(m_ir));
save_item(NAME(m_ird));
save_item(NAME(m_ftu));
save_item(NAME(m_aluo));
save_item(NAME(m_alue));
save_item(NAME(m_alub));
save_item(NAME(m_movemr));
save_item(NAME(m_irdi));
save_item(NAME(m_base_ssw));
save_item(NAME(m_ssw));
save_item(NAME(m_dcr));
save_item(NAME(m_virq_state));
save_item(NAME(m_nmi_pending));
save_item(NAME(m_int_level));
save_item(NAME(m_int_next_state));
save_item(NAME(m_nmi_uses_generic));
save_item(NAME(m_last_vpa_time));
save_item(NAME(m_inst_state));
save_item(NAME(m_inst_substate));
save_item(NAME(m_next_state));
save_item(NAME(m_post_run));
save_item(NAME(m_post_run_cycles));
memset(m_da, 0, sizeof(m_da));
m_ipc = 0;
m_pc = 0;
m_au = 0;
m_at = 0;
m_aob = 0;
m_dt = 0;
m_int_vector = 0;
m_sp = 0;
m_bcount = 0;
m_count_before_instruction_step = 0;
m_t = 0;
m_movems = 0;
m_isr = 0;
m_sr = 0;
m_new_sr = 0;
m_dbin = 0;
m_dbout = 0;
m_edb = 0;
m_irc = 0;
m_ir = 0;
m_ird = 0;
m_ftu = 0;
m_aluo = 0;
m_alue = 0;
m_alub = 0;
m_movemr = 0;
m_irdi = 0;
m_base_ssw = 0;
m_ssw = 0;
m_dcr = 0;
m_virq_state = 0;
m_nmi_pending = 0;
m_int_level = 0;
m_int_next_state = 0;
m_nmi_uses_generic = false;
m_last_vpa_time = 0;
m_inst_state = 0;
m_inst_substate = 0;
m_next_state = 0;
m_post_run = 0;
m_post_run_cycles = 0;
state_add(STATE_GENPCBASE, "CURPC", m_ipc).callimport();
state_add(STATE_GENPC, "PC", m_pc).callimport();
state_add(M68K_IR, "IR", m_ir);
state_add(STATE_GENFLAGS, "GENFLAGS", m_sr).noshow().callexport().formatstr("%16s");
state_add(M68K_SR, "SR", m_sr).callimport();
for(int r = 0; r != 8; r++)
state_add(M68K_D0 + r, string_format("D%d", r).c_str(), m_da[r]);
for(int r = 0; r != 7; r++)
state_add(M68K_A0 + r, string_format("A%d", r).c_str(), m_da[r+8]);
state_add(M68K_USP, "USP", m_da[15]);
state_add(M68K_SP, "SP", m_da[16]);
set_icountptr(m_icount);
}
void m68000_device::state_import(const device_state_entry &entry)
{
switch(entry.index()) {
case STATE_GENPC:
m_ipc = m_pc;
[[fallthrough]];
case STATE_GENPCBASE: {
m_pc = m_ipc+2;
m_au = m_ipc+4;
auto dis = machine().disable_side_effects();
m_ir = m_ird = m_irdi = m_opcodes.read_word(m_ipc);
m_irc = m_dbin = m_opcodes.read_word(m_pc);
set_ftu_const();
m_inst_state = m_decode_table[m_ird];
m_inst_substate = 0;
break;
}
case M68K_SR:
m_sr &= (SR_SR|SR_CCR);
break;
}
}
void m68000_device::state_string_export(const device_state_entry &entry, std::string &str) const
{
switch(entry.index()) {
case STATE_GENFLAGS:
str = util::string_format("%c%c%d %c%c%c%c%c",
m_sr & SR_T ? 'T' : '.',
m_sr & SR_S ? 'S' : '.',
(m_sr & SR_I) >> 8,
m_sr & SR_X ? 'X' : '.',
m_sr & SR_N ? 'N' : '.',
m_sr & SR_Z ? 'Z' : '.',
m_sr & SR_V ? 'V' : '.',
m_sr & SR_C ? 'C' : '.');
break;
}
}
void m68000_device::device_reset()
{
m_inst_state = S_RESET;
m_inst_substate = 0;
m_count_before_instruction_step = 0;
m_post_run = 0;
m_post_run_cycles = 0;
m_last_vpa_time = 0;
update_user_super();
}
void m68000_device::update_user_super()
{
if(m_sr & SR_S) {
m_sp = 16;
m_program = m_r_program;
m_opcodes = m_r_opcodes;
if(m_mmu)
m_mmu->set_super(true);
} else {
m_sp = 15;
m_program = m_r_uprogram;
m_opcodes = m_r_uopcodes;
if(m_mmu)
m_mmu->set_super(false);
}
}
void m68000_device::execute_set_input(int inputnum, int state)
{
if(inputnum == INPUT_LINE_NMI) {
inputnum = 7;
m_nmi_uses_generic = true;
} else if(inputnum == 7)
m_nmi_uses_generic = false;
if(inputnum > (m_interrupt_mixer ? 7 : 3))
return;
u32 old_level = m_int_level;
u32 vstate = m_virq_state;
u32 blevel;
if(state == ASSERT_LINE)
vstate |= 1 << inputnum;
else
vstate &= ~(1 << inputnum);
m_virq_state = vstate;
if(m_interrupt_mixer) {
for(blevel = 7; blevel > 0; blevel--)
if(vstate & (1 << blevel))
break;
} else
blevel = vstate;
m_int_level = blevel;
/* A transition from < 7 to 7 always interrupts (NMI) */
/* Note: Level 7 can also level trigger like a normal IRQ */
// FIXME: This may cause unintended level 7 interrupts if one or two IPL lines are asserted
// immediately before others are cleared. The actual 68000 imposes an input hold time.
if(old_level != 7 && m_int_level == 7)
m_nmi_pending = true;
update_interrupt();
}
void m68000_device::update_interrupt()
{
if(m_nmi_pending)
m_int_next_state = (7 << 24) | S_INTERRUPT;
else if(m_int_level > ((m_sr >> 8) & 7))
m_int_next_state = (m_int_level << 24) | S_INTERRUPT;
else
m_int_next_state = 0;
}
void m68000_device::init_decode_table()
{
m_decode_table.resize(0x10000, S_ILLEGAL);
for(int i=0; s_packed_decode_table[i].mask; i++) {
u16 value = s_packed_decode_table[i].value;
u16 mask = s_packed_decode_table[i].mask;
u16 state = s_packed_decode_table[i].state;
u16 cvalue = 0;
do {
// logerror("%04x/%04x %04x %4d\n", value, mask, cvalue, state);
if(m_decode_table[value | cvalue] == S_ILLEGAL)
m_decode_table[value | cvalue] = state;
else if(((value | cvalue) & 0xf0ff) != 0x6000)
logerror("Collision on %04x (%d / %d)\n", value | cvalue, state, m_decode_table[value | cvalue]);
cvalue = ((cvalue | mask) + 1) & ~mask;
} while(cvalue);
}
}
void m68000_device::set_ftu_const()
{
switch(m_ird >> 12) {
case 0x4: m_ftu = 0x80; break;
case 0x5: case 0xe: m_ftu = (m_ird >> 9) & 7; if(!m_ftu) m_ftu = 8; break;
case 0x6: case 0x7: m_ftu = s8(m_ird); break;
case 0x8: case 0xc: m_ftu = 0xf; break;
default: m_ftu = 0; break;
}
}
void m68000_device::start_interrupt_vector_lookup()
{
// flag for berr -> spurious
int level = m_next_state >> 24;
if(!m_disable_interrupt_callback) {
if(m_interrupt_mixer)
standard_irq_callback(level == 7 && m_nmi_uses_generic ? INPUT_LINE_NMI : level, m_pc);
else {
for(int i=0; i<3; i++)
if(level & (1<<i))
standard_irq_callback(i, m_pc);
}
}
// Clear the nmi flag
if(level == 7) {
m_nmi_pending = false;
update_interrupt();
}
}
void m68000_device::end_interrupt_vector_lookup()
{
m_int_vector = (m_edb & 0xff) << 2;
m_int_next_state = 0;
}
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