86Box/src/chipset/ali1429.c

/*
 * 86Box	A hypervisor and IBM PC system emulator that specializes in
 *		running old operating systems and software designed for IBM
 *		PC systems and compatibles from 1981 through fairly recent
 *		system designs based on the PCI bus.
 *
 *		This file is part of the 86Box distribution.
 *
 *		Implementation of the ALi M1429 chipset.
 *
 *      Note: This chipset has no datasheet, everything were done via
 *      reverse engineering the BIOS of various machines using it.
 *
 *      Authors: Tiseno100
 *
 *		Copyright 2020 Tiseno100
 *
 */

#include <stdarg.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>
#define HAVE_STDARG_H
#include <86box/86box.h>
#include "cpu.h"
#include <86box/timer.h>
#include <86box/io.h>
#include <86box/device.h>

#include <86box/apm.h>
#include <86box/mem.h>
#include <86box/fdd.h>
#include <86box/fdc.h>
#include <86box/port_92.h>
#include <86box/smram.h>
#include <86box/chipset.h>

#define disabled_shadow (MEM_READ_EXTANY | MEM_WRITE_EXTANY)

#ifdef ENABLE_ALI1429_LOG
int ali1429_do_log = ENABLE_ALI1429_LOG;
static void
ali1429_log(const char *fmt, ...)
{
    va_list ap;

    if (ali1429_do_log)
    {
        va_start(ap, fmt);
        pclog_ex(fmt, ap);
        va_end(ap);
    }
}
#else
#define ali1429_log(fmt, ...)
#endif

typedef struct
{
    uint8_t index, cfg_locked,
        regs[256];

    smram_t *smram;
} ali1429_t;

static void ali1429_shadow_recalc(ali1429_t *dev)
{

    uint32_t base, i, can_write, can_read;

    shadowbios = (dev->regs[0x13] & 0x40) && (dev->regs[0x14] & 0x01);
    shadowbios_write = (dev->regs[0x13] & 0x40) && (dev->regs[0x14] & 0x02);

    can_write = (dev->regs[0x14] & 0x02) ? MEM_WRITE_INTERNAL : MEM_WRITE_EXTANY;
    can_read = (dev->regs[0x14] & 0x01) ? MEM_READ_INTERNAL : MEM_READ_EXTANY;

    for (i = 0; i < 8; i++)
    {
        base = 0xc0000 + (i << 15);

        if (dev->regs[0x13] & (1 << i))
            mem_set_mem_state_both(base, 0x8000, can_read | can_write);
        else
            mem_set_mem_state_both(base, 0x8000, disabled_shadow);
    }

    flushmmucache();
}

static void
ali1429_write(uint16_t addr, uint8_t val, void *priv)
{
    ali1429_t *dev = (ali1429_t *)priv;

    switch (addr)
    {
    case 0x22:
        dev->index = val;
        break;

    case 0x23:
        if (dev->index != 0x03)
            ali1429_log("M1429: dev->regs[%02x] = %02x\n", dev->index, val);

        if (dev->index == 0x03)
            dev->cfg_locked = !(val == 0xc5);

        if (!dev->cfg_locked)
        {
            dev->regs[dev->index] = val;

            switch (dev->index)
            {
            case 0x13:
            case 0x14:
                ali1429_shadow_recalc(dev);
                break;

            case 0x18:
                cpu_cache_ext_enabled = !!(val & 2);
                cpu_update_waitstates();
                break;
            }
        }

        break;
    }
}

static uint8_t
ali1429_read(uint16_t addr, void *priv)
{
    ali1429_t *dev = (ali1429_t *)priv;
    return (addr == 0x23) ? dev->regs[dev->index] : 0xff;
}

static void
ali1429_close(void *priv)
{
    ali1429_t *dev = (ali1429_t *)priv;

    free(dev);
}

static void *
ali1429_init(const device_t *info)
{
    ali1429_t *dev = (ali1429_t *)malloc(sizeof(ali1429_t));
    memset(dev, 0, sizeof(ali1429_t));

    /*
    M1429 Ports:
    22h Index Port
    23h Data Port
    */
    io_sethandler(0x0022, 0x0002, ali1429_read, NULL, NULL, ali1429_write, NULL, NULL, dev);

    dev->cfg_locked = 1;

    device_add(&apm_device);
    device_add(&port_92_device);
    /* dev->smram = smram_add(); */

    return dev;
}

const device_t ali1429_device = {
    "ALi M1429",
    0,
    0,
    ali1429_init,
    ali1429_close,
    NULL,
    {NULL},
    NULL,
    NULL,
    NULL};