/****************************************************************************
 *  Twin Cobra                                                              *
 *  Communications and memory functions between shared CPU memory spaces    *
 ****************************************************************************/

#include "driver.h"
#include "cpu/m68000/m68000.h"
#include "cpu/tms32010/tms32010.h"
#include "twincobr.h"


#define LOG_DSP_CALLS 0
#define CLEAR  0
#define ASSERT 1


int toaplan_main_cpu;	/* Main CPU type.  0 = 68000, 1 = Z80 */
int twincobr_intenable;
int wardner_membank;
static int twincobr_dsp_on;
static int twincobr_dsp_BIO;
static int fsharkbt_8741;
static int dsp_execute;
static UINT32 dsp_addr_w, main_ram_seg;

#if LOG_DSP_CALLS
static const int toaplan_port_type[2] = { 0x7800c, 0x5c };
#endif

UINT8 *twincobr_sharedram;



INTERRUPT_GEN( twincobr_interrupt )
{
	if (twincobr_intenable) {
		twincobr_intenable = 0;
		cpunum_set_input_line(0, MC68000_IRQ_4, HOLD_LINE);
	}
}

INTERRUPT_GEN( wardner_interrupt )
{
	if (twincobr_intenable) {
		twincobr_intenable = 0;
		cpunum_set_input_line(0, 0, HOLD_LINE);
	}
}


WRITE16_HANDLER( twincobr_dsp_addrsel_w )
{
	/* This sets the main CPU RAM address the DSP should */
	/*  read/write, via the DSP IO port 0 */
	/* Top three bits of data need to be shifted left 3 places */
	/*  to select which memory bank from main CPU address */
	/*  space to use */
	/* Lower thirteen bits of this data is shifted left one position */
	/*  to move it to an even address word boundary */

	main_ram_seg = ((data & 0xe000) << 3);
	dsp_addr_w   = ((data & 0x1fff) << 1);

#if LOG_DSP_CALLS
	logerror("DSP PC:%04x IO write %04x (%08x) at port 0\n",activecpu_get_previouspc(),data,main_ram_seg + dsp_addr_w);
#endif
}

READ16_HANDLER( twincobr_dsp_r )
{
	/* DSP can read data from main CPU RAM via DSP IO port 1 */

	UINT16 input_data = 0;
	switch (main_ram_seg) {
		case 0x30000:
		case 0x40000:
		case 0x50000:	cpuintrf_push_context(0);
						input_data = program_read_word(main_ram_seg + dsp_addr_w);
						cpuintrf_pop_context(); break;
		default:		logerror("DSP PC:%04x Warning !!! IO reading from %08x (port 1)\n",activecpu_get_previouspc(),main_ram_seg + dsp_addr_w); break;
	}
#if LOG_DSP_CALLS
	logerror("DSP PC:%04x IO read %04x at %08x (port 1)\n",activecpu_get_previouspc(),input_data,main_ram_seg + dsp_addr_w);
#endif
	return input_data;
}

WRITE16_HANDLER( twincobr_dsp_w )
{
	/* Data written to main CPU RAM via DSP IO port 1 */
	dsp_execute = 0;
	switch (main_ram_seg) {
		case 0x30000:	if ((dsp_addr_w < 3) && (data == 0)) dsp_execute = 1;
		case 0x40000:
		case 0x50000:	cpuintrf_push_context(0);
						program_write_word(main_ram_seg + dsp_addr_w, data);
						cpuintrf_pop_context(); break;
		default:		logerror("DSP PC:%04x Warning !!! IO writing to %08x (port 1)\n",activecpu_get_previouspc(),main_ram_seg + dsp_addr_w); break;
	}
#if LOG_DSP_CALLS
	logerror("DSP PC:%04x IO write %04x at %08x (port 1)\n",activecpu_get_previouspc(),data,main_ram_seg + dsp_addr_w);
#endif
}

WRITE16_HANDLER( wardner_dsp_addrsel_w )
{
	/* This sets the main CPU RAM address the DSP should */
	/*  read/write, via the DSP IO port 0 */
	/* Lower twelve bits of this data is shifted left one position */
	/*  to move it to an even address boundary */

	main_ram_seg =  (data & 0xe000);
	dsp_addr_w   = ((data & 0x07ff) << 1);

	if (main_ram_seg == 0x6000) main_ram_seg = 0x7000;

#if LOG_DSP_CALLS
	logerror("DSP PC:%04x IO write %04x (%08x) at port 0\n",activecpu_get_previouspc(),data,main_ram_seg + dsp_addr_w);
#endif
}

READ16_HANDLER( wardner_dsp_r )
{
	/* DSP can read data from main CPU RAM via DSP IO port 1 */

	UINT16 input_data = 0;
	switch (main_ram_seg) {
		case 0x7000:
		case 0x8000:
		case 0xa000:	cpuintrf_push_context(0);
						input_data =  program_read_byte(main_ram_seg + (dsp_addr_w + 0))
								   | (program_read_byte(main_ram_seg + (dsp_addr_w + 1)) << 8);
						cpuintrf_pop_context(); break;
		default:		logerror("DSP PC:%04x Warning !!! IO reading from %08x (port 1)\n",activecpu_get_previouspc(),main_ram_seg + dsp_addr_w); break;
	}
#if LOG_DSP_CALLS
	logerror("DSP PC:%04x IO read %04x at %08x (port 1)\n",activecpu_get_previouspc(),input_data,main_ram_seg + dsp_addr_w);
#endif
	return input_data;
}

WRITE16_HANDLER( wardner_dsp_w )
{
	/* Data written to main CPU RAM via DSP IO port 1 */
	dsp_execute = 0;
	switch (main_ram_seg) {
		case 0x7000:	if ((dsp_addr_w < 3) && (data == 0)) dsp_execute = 1;
		case 0x8000:
		case 0xa000:	cpuintrf_push_context(0);
						program_write_byte(main_ram_seg + (dsp_addr_w + 0), (data & 0xff));
						program_write_byte(main_ram_seg + (dsp_addr_w + 1), ((data >> 8) & 0xff));
						cpuintrf_pop_context(); break;
		default:		logerror("DSP PC:%04x Warning !!! IO writing to %08x (port 1)\n",activecpu_get_previouspc(),main_ram_seg + dsp_addr_w); break;
	}
#if LOG_DSP_CALLS
	logerror("DSP PC:%04x IO write %04x at %08x (port 1)\n",activecpu_get_previouspc(),data,main_ram_seg + dsp_addr_w);
#endif
}

WRITE16_HANDLER( twincobr_dsp_bio_w )
{
	/* data 0xffff  means inhibit BIO line to DSP and enable */
	/*              communication to main processor */
	/*              Actually only DSP data bit 15 controls this */
	/* data 0x0000  means set DSP BIO line active and disable */
	/*              communication to main processor*/
#if LOG_DSP_CALLS
	logerror("DSP PC:%04x IO write %04x at port 3\n",activecpu_get_previouspc(),data);
#endif
	if (data & 0x8000) {
		twincobr_dsp_BIO = CLEAR_LINE;
	}
	if (data == 0) {
		if (dsp_execute) {
#if LOG_DSP_CALLS
			logerror("Turning the main CPU on\n");
#endif
			cpunum_set_input_line(0, INPUT_LINE_HALT, CLEAR_LINE);
			dsp_execute = 0;
		}
		twincobr_dsp_BIO = ASSERT_LINE;
	}
}

READ16_HANDLER( fsharkbt_dsp_r )
{
	/* IO Port 2 used by Flying Shark bootleg */
	/* DSP reads data from an extra MCU (8741) at IO port 2 */
	/* Port is read three times during startup. First and last data */
	/*   read must equal, but second data read must be different */
	fsharkbt_8741 += 1;
#if LOG_DSP_CALLS
	logerror("DSP PC:%04x IO read %04x from 8741 MCU (port 2)\n",activecpu_get_previouspc(),(fsharkbt_8741 & 0x08));
#endif
	return (fsharkbt_8741 & 1);
}

WRITE16_HANDLER( fsharkbt_dsp_w )
{
	/* Flying Shark bootleg DSP writes data to an extra MCU (8741) at IO port 2 */
#if 0
	logerror("DSP PC:%04x IO write from DSP RAM:%04x to 8741 MCU (port 2)\n",activecpu_get_previouspc(),fsharkbt_8741);
#endif
}

READ16_HANDLER ( twincobr_BIO_r )
{
	return twincobr_dsp_BIO;
}


static void twincobr_dsp(int enable)
{
	twincobr_dsp_on = enable;
	if (enable) {
#if LOG_DSP_CALLS
		logerror("Turning DSP on and main CPU off\n");
#endif
		cpunum_set_input_line(2, INPUT_LINE_HALT, CLEAR_LINE);
		cpunum_set_input_line(2, 0, ASSERT_LINE); /* TMS32010 INT */
		cpunum_set_input_line(0, INPUT_LINE_HALT, ASSERT_LINE);
	}
	else {
#if LOG_DSP_CALLS
		logerror("Turning DSP off\n");
#endif
		cpunum_set_input_line(2, 0, CLEAR_LINE); /* TMS32010 INT */
		cpunum_set_input_line(2, INPUT_LINE_HALT, ASSERT_LINE);
	}
}

static void twincobr_restore_dsp(void)
{
	twincobr_dsp(twincobr_dsp_on);
}


static void toaplan0_control_w(int offset, int data)
{
#if LOG_DSP_CALLS
	logerror("CPU0:%08x  Writing %08x to %08x.\n",activecpu_get_pc(),data,toaplan_port_type[toaplan_main_cpu] - offset);
#endif

	if (toaplan_main_cpu == 1) {
		if (data == 0x0c) { data = 0x1c; wardner_sprite_hack=0; }	/* Z80 ? */
		if (data == 0x0d) { data = 0x1d; wardner_sprite_hack=1; }	/* Z80 ? */
	}

	switch (data) {
		case 0x0004: twincobr_intenable = 0; break;
		case 0x0005: twincobr_intenable = 1; break;
		case 0x0006: twincobr_flipscreen(0); break;
		case 0x0007: twincobr_flipscreen(1); break;
		case 0x0008: twincobr_bg_ram_bank = 0x0000; break;
		case 0x0009: twincobr_bg_ram_bank = 0x1000; break;
		case 0x000a: twincobr_fg_rom_bank = 0x0000; break;
		case 0x000b: twincobr_fg_rom_bank = 0x1000; break;
		case 0x000c: twincobr_dsp(1); break;	 /* Enable the INT line to the DSP */
		case 0x000d: twincobr_dsp(0); break;	 /* Inhibit the INT line to the DSP */
		case 0x000e: twincobr_display(0); break; /* Turn display off */
		case 0x000f: twincobr_display(1); break; /* Turn display on */
	}
}

WRITE16_HANDLER( twincobr_control_w )
{
	if (ACCESSING_LSB)
	{
		toaplan0_control_w(offset, data & 0xff);
	}
}

WRITE8_HANDLER( wardner_control_w )
{
	toaplan0_control_w(offset, data);
}


READ16_HANDLER( twincobr_sharedram_r )
{
	return twincobr_sharedram[offset];
}

WRITE16_HANDLER( twincobr_sharedram_w )
{
	if (ACCESSING_LSB)
	{
		twincobr_sharedram[offset] = data & 0xff;
	}
}


static void toaplan0_coin_dsp_w(int offset, int data)
{
#if LOG_DSP_CALLS
	if (data > 1)
		logerror("CPU0:%08x  Writing %08x to %08x.\n",activecpu_get_pc(),data,toaplan_port_type[toaplan_main_cpu] - offset);
#endif
	switch (data) {
		case 0x08: coin_counter_w(0,0); break;
		case 0x09: coin_counter_w(0,1); break;
		case 0x0a: coin_counter_w(1,0); break;
		case 0x0b: coin_counter_w(1,1); break;
		case 0x0c: coin_lockout_w(0,1); break;
		case 0x0d: coin_lockout_w(0,0); break;
		case 0x0e: coin_lockout_w(1,1); break;
		case 0x0f: coin_lockout_w(1,0); break;
		/****** The following apply to Flying Shark/Wardner only ******/
		case 0x00:	/* This means assert the INT line to the DSP */
#if LOG_DSP_CALLS
					logerror("Turning DSP on and main CPU off\n");
#endif
					cpunum_set_input_line(2, INPUT_LINE_HALT, CLEAR_LINE);
					cpunum_set_input_line(2, 0, ASSERT_LINE); /* TMS32010 INT */
					cpunum_set_input_line(0, INPUT_LINE_HALT, ASSERT_LINE);
					break;
		case 0x01:	/* This means inhibit the INT line to the DSP */
#if LOG_DSP_CALLS
					logerror("Turning DSP off\n");
#endif
					cpunum_set_input_line(2, 0, CLEAR_LINE); /* TMS32010 INT */
					cpunum_set_input_line(2, INPUT_LINE_HALT, ASSERT_LINE);
					break;
	}
}


WRITE16_HANDLER( fshark_coin_dsp_w )
{
	if (ACCESSING_LSB)
	{
		toaplan0_coin_dsp_w(offset, data & 0xff);
	}
}

WRITE8_HANDLER( twincobr_coin_w )
{
	toaplan0_coin_dsp_w(offset, data);
}

WRITE8_HANDLER( wardner_coin_dsp_w )
{
	toaplan0_coin_dsp_w(offset, data);
}


MACHINE_RESET( twincobr )
{
	toaplan_main_cpu = 0;		/* 68000 */
	twincobr_display(0);
	twincobr_intenable = 0;
	dsp_addr_w = 0;
	main_ram_seg = 0;
	dsp_execute = 0;
	fsharkbt_8741 = -1;			/* Reset the Flying Shark Bootleg MCU */
	twincobr_dsp_BIO = CLEAR_LINE;
}
void twincobr_driver_savestate(void)
{
	state_save_register_global(toaplan_main_cpu);
	state_save_register_global(twincobr_intenable);
	state_save_register_global(twincobr_dsp_on);
	state_save_register_global(dsp_addr_w);
	state_save_register_global(main_ram_seg);
	state_save_register_global(twincobr_dsp_BIO);
	state_save_register_global(dsp_execute);
	state_save_register_global(fsharkbt_8741);
	state_save_register_func_postload(twincobr_restore_dsp);
}

MACHINE_RESET( wardner )
{
	toaplan_main_cpu = 1;		/* Z80 */
	twincobr_display(1);
	twincobr_intenable = 0;
	dsp_addr_w = 0;
	main_ram_seg = 0;
	dsp_execute = 0;
	twincobr_dsp_BIO = CLEAR_LINE;
	wardner_membank = 0;
}
void wardner_driver_savestate(void)
{
	state_save_register_global(toaplan_main_cpu);
	state_save_register_global(twincobr_intenable);
	state_save_register_global(twincobr_dsp_on);
	state_save_register_global(dsp_addr_w);
	state_save_register_global(main_ram_seg);
	state_save_register_global(twincobr_dsp_BIO);
	state_save_register_global(dsp_execute);
	state_save_register_global(wardner_membank);
	state_save_register_func_postload(wardner_restore_bank);	/* Restore the Main CPU bank */
	state_save_register_func_postload(twincobr_restore_dsp);
}
