86Box/src/machine/m_xt_laserxt.c

/*This is the chipset used in the LaserXT series model*/
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <wchar.h>
#include <86box/86box.h>
#include "cpu.h"
#include <86box/io.h>
#include <86box/mem.h>
#include <86box/nmi.h>
#include <86box/timer.h>
#include <86box/pit.h>
#include <86box/rom.h>
#include <86box/machine.h>
#include <86box/device.h>
#include <86box/timer.h>
#include <86box/fdd.h>
#include <86box/fdc.h>
#include <86box/fdc_ext.h>
#include <86box/gameport.h>
#include <86box/keyboard.h>
#include <86box/plat_unused.h>

static int           laserxt_emspage[4];
static int           laserxt_emscontrol[4];
static mem_mapping_t laserxt_ems_mapping[4];
static int           laserxt_ems_baseaddr_index = 0;
static int           laserxt_is_lxt3            = 0;

static uint32_t
get_laserxt_ems_addr(uint32_t addr)
{
    if (laserxt_emspage[(addr >> 14) & 3] & 0x80) {
        addr = (!laserxt_is_lxt3 ? 0x70000 + (((mem_size + 64) & 255) << 10) : 0x30000 + (((mem_size + 320) & 511) << 10)) + ((laserxt_emspage[(addr >> 14) & 3] & 0x0F) << 14) + ((laserxt_emspage[(addr >> 14) & 3] & 0x40) << 12) + (addr & 0x3FFF);
    }

    return addr;
}

static void
laserxt_write(uint16_t port, uint8_t val, UNUSED(void *priv))
{
    uint32_t paddr;
    uint32_t vaddr;
    switch (port) {
        case 0x0208:
        case 0x4208:
        case 0x8208:
        case 0xC208:
            laserxt_emspage[port >> 14] = val;
            paddr                       = 0xC0000 + (port & 0xC000) + (((laserxt_ems_baseaddr_index + (4 - (port >> 14))) & 0x0C) << 14);
            if (val & 0x80) {
                mem_mapping_enable(&laserxt_ems_mapping[port >> 14]);
                vaddr = get_laserxt_ems_addr(paddr);
                mem_mapping_set_exec(&laserxt_ems_mapping[port >> 14], ram + vaddr);
            } else {
                mem_mapping_disable(&laserxt_ems_mapping[port >> 14]);
            }
            flushmmucache();
            break;
        case 0x0209:
        case 0x4209:
        case 0x8209:
        case 0xC209:
            laserxt_emscontrol[port >> 14] = val;
            laserxt_ems_baseaddr_index     = 0;
            for (uint8_t i = 0; i < 4; i++) {
                laserxt_ems_baseaddr_index |= (laserxt_emscontrol[i] & 0x80) >> (7 - i);
            }

            mem_mapping_set_addr(&laserxt_ems_mapping[0], 0xC0000 + (((laserxt_ems_baseaddr_index + 4) & 0x0C) << 14), 0x4000);
            mem_mapping_set_addr(&laserxt_ems_mapping[1], 0xC4000 + (((laserxt_ems_baseaddr_index + 3) & 0x0C) << 14), 0x4000);
            mem_mapping_set_addr(&laserxt_ems_mapping[2], 0xC8000 + (((laserxt_ems_baseaddr_index + 2) & 0x0C) << 14), 0x4000);
            mem_mapping_set_addr(&laserxt_ems_mapping[3], 0xCC000 + (((laserxt_ems_baseaddr_index + 1) & 0x0C) << 14), 0x4000);
            flushmmucache();
            break;

        default:
            break;
    }
}

static uint8_t
laserxt_read(uint16_t port, UNUSED(void *priv))
{
    switch (port) {
        case 0x0208:
        case 0x4208:
        case 0x8208:
        case 0xC208:
            return laserxt_emspage[port >> 14];
        case 0x0209:
        case 0x4209:
        case 0x8209:
        case 0xC209:
            return laserxt_emscontrol[port >> 14];

        default:
            break;
    }
    return 0xff;
}

static void
mem_write_laserxtems(uint32_t addr, uint8_t val, UNUSED(void *priv))
{
    addr = get_laserxt_ems_addr(addr);
    if (addr < (mem_size << 10))
        ram[addr] = val;
}

static uint8_t
mem_read_laserxtems(uint32_t addr, UNUSED(void *priv))
{
    uint8_t val = 0xFF;
    addr        = get_laserxt_ems_addr(addr);
    if (addr < (mem_size << 10))
        val = ram[addr];
    return val;
}

static void
laserxt_init(int is_lxt3)
{
    if (mem_size > 640) {
        io_sethandler(0x0208, 0x0002, laserxt_read, NULL, NULL, laserxt_write, NULL, NULL, NULL);
        io_sethandler(0x4208, 0x0002, laserxt_read, NULL, NULL, laserxt_write, NULL, NULL, NULL);
        io_sethandler(0x8208, 0x0002, laserxt_read, NULL, NULL, laserxt_write, NULL, NULL, NULL);
        io_sethandler(0xc208, 0x0002, laserxt_read, NULL, NULL, laserxt_write, NULL, NULL, NULL);
        mem_mapping_set_addr(&ram_low_mapping, 0, !is_lxt3 ? 0x70000 + (((mem_size + 64) & 255) << 10) : 0x30000 + (((mem_size + 320) & 511) << 10));
    }

    for (uint8_t i = 0; i < 4; i++) {
        laserxt_emspage[i]    = 0x7F;
        laserxt_emscontrol[i] = (i == 3) ? 0x00 : 0x80;
        mem_mapping_add(&laserxt_ems_mapping[i], 0xE0000 + (i << 14), 0x4000, mem_read_laserxtems, NULL, NULL, mem_write_laserxtems, NULL, NULL, ram + 0xA0000 + (i << 14), 0, NULL);
        mem_mapping_disable(&laserxt_ems_mapping[i]);
    }
    mem_set_mem_state(0x0c0000, 0x40000, MEM_READ_EXTANY | MEM_WRITE_EXTANY);
    laserxt_is_lxt3 = is_lxt3;
}

static void
machine_xt_laserxt_common_init(const machine_t *model,int is_lxt3)
{
    machine_common_init(model);

    pit_devs[0].set_out_func(pit_devs[0].data, 1, pit_refresh_timer_xt);

    if (fdc_type == FDC_INTERNAL)
        device_add(&fdc_xt_device);

    nmi_init();
    standalone_gameport_type = &gameport_device;

    laserxt_init(is_lxt3);
}

int
machine_xt_laserxt_init(const machine_t *model)
{
    int ret;

    ret = bios_load_linear("roms/machines/ltxt/27c64.bin",
                           0x000fe000, 8192, 0);

    if (bios_only || !ret)
        return ret;

    device_add(&keyboard_xt_device);

    machine_xt_laserxt_common_init(model, 0);

    return ret;
}

int
machine_xt_lxt3_init(const machine_t *model)
{
    int ret;

    ret = bios_load_linear("roms/machines/lxt3/27c64d.bin",
                           0x000fe000, 8192, 0);

    if (bios_only || !ret)
        return ret;

    device_add(&keyboard_xt_lxt3_device);

    machine_xt_laserxt_common_init(model, 1);

    return ret;
}