/*
 * 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 M1541/2 CPU-to-PCI Bridge.
 *
 * Authors: Miran Grca, <mgrca8@gmail.com>
 *
 *          Copyright 2021 Miran Grca.
 */
#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/device.h>
#include <86box/io.h>
#include <86box/mem.h>
#include <86box/pci.h>
#include <86box/plat_unused.h>
#include <86box/smram.h>
#include <86box/spd.h>

#include <86box/chipset.h>

typedef struct ali1541_t {
    uint8_t pci_slot;
    uint8_t pad;
    uint8_t pad0;
    uint8_t pad1;

    uint8_t pci_conf[256];

    smram_t *smram;
    void    *agp_bridge;
} ali1541_t;

#ifdef ENABLE_ALI1541_LOG
int ali1541_do_log = ENABLE_ALI1541_LOG;

static void
ali1541_log(const char *fmt, ...)
{
    va_list ap;

    if (ali1541_do_log) {
        va_start(ap, fmt);
        pclog_ex(fmt, ap);
        va_end(ap);
    }
}
#else
#    define ali1541_log(fmt, ...)
#endif

static void
ali1541_smram_recalc(uint8_t val, ali1541_t *dev)
{
    smram_disable_all();

    if (val & 1) {
        switch (val & 0x0c) {
            case 0x00:
                ali1541_log("SMRAM: D0000 -> B0000 (%i)\n", val & 2);
                smram_enable(dev->smram, 0xd0000, 0xb0000, 0x10000, val & 2, 1);
                if (val & 0x10)
                    mem_set_mem_state_smram_ex(1, 0xd0000, 0x10000, 0x02);
                break;
            case 0x04:
                ali1541_log("SMRAM: A0000 -> A0000 (%i)\n", val & 2);
                smram_enable(dev->smram, 0xa0000, 0xa0000, 0x20000, val & 2, 1);
                if (val & 0x10)
                    mem_set_mem_state_smram_ex(1, 0xa0000, 0x20000, 0x02);
                break;
            case 0x08:
                ali1541_log("SMRAM: 30000 -> B0000 (%i)\n", val & 2);
                smram_enable(dev->smram, 0x30000, 0xb0000, 0x10000, val & 2, 1);
                if (val & 0x10)
                    mem_set_mem_state_smram_ex(1, 0x30000, 0x10000, 0x02);
                break;
            default:
                break;
        }
    }

    flushmmucache_nopc();
}

static void
ali1541_shadow_recalc(UNUSED(int cur_reg), ali1541_t *dev)
{
    int      bit;
    int      r_reg;
    int      w_reg;
    uint32_t base;
    uint32_t flags = 0;

    shadowbios = shadowbios_write = 0;

    for (uint8_t i = 0; i < 16; i++) {
        base  = 0x000c0000 + (i << 14);
        bit   = i & 7;
        r_reg = 0x56 + (i >> 3);
        w_reg = 0x58 + (i >> 3);

        flags = (dev->pci_conf[r_reg] & (1 << bit)) ? MEM_READ_INTERNAL : MEM_READ_EXTANY;
        flags |= ((dev->pci_conf[w_reg] & (1 << bit)) ? MEM_WRITE_INTERNAL : MEM_WRITE_EXTANY);

        if (base >= 0x000e0000) {
            if (dev->pci_conf[r_reg] & (1 << bit))
                shadowbios |= 1;
            if (dev->pci_conf[w_reg] & (1 << bit))
                shadowbios_write |= 1;
        }

        ali1541_log("%08X-%08X shadow: R%c, W%c\n", base, base + 0x00003fff,
                    (dev->pci_conf[r_reg] & (1 << bit)) ? 'I' : 'E', (dev->pci_conf[w_reg] & (1 << bit)) ? 'I' : 'E');
        mem_set_mem_state_both(base, 0x00004000, flags);
    }

    flushmmucache_nopc();
}

static void
ali1541_mask_bar(ali1541_t *dev)
{
    uint32_t bar;
    uint32_t mask;

    switch (dev->pci_conf[0xbc] & 0x0f) {
        default:
        case 0x00:
            mask = 0x00000000;
            break;
        case 0x01:
            mask = 0xfff00000;
            break;
        case 0x02:
            mask = 0xffe00000;
            break;
        case 0x03:
            mask = 0xffc00000;
            break;
        case 0x04:
            mask = 0xff800000;
            break;
        case 0x06:
            mask = 0xff000000;
            break;
        case 0x07:
            mask = 0xfe000000;
            break;
        case 0x08:
            mask = 0xfc000000;
            break;
        case 0x09:
            mask = 0xf8000000;
            break;
        case 0x0a:
            mask = 0xf0000000;
            break;
    }

    bar                 = ((dev->pci_conf[0x13] << 24) | (dev->pci_conf[0x12] << 16)) & mask;
    dev->pci_conf[0x12] = (bar >> 16) & 0xff;
    dev->pci_conf[0x13] = (bar >> 24) & 0xff;
}

static void
ali1541_write(UNUSED(int func), int addr, uint8_t val, void *priv)
{
    ali1541_t *dev = (ali1541_t *) priv;

    switch (addr) {
        case 0x04:
            dev->pci_conf[addr] = val;
            break;
        case 0x05:
            dev->pci_conf[addr] = val & 0x01;
            break;

        case 0x07:
            dev->pci_conf[addr] &= ~(val & 0xf8);
            break;

        case 0x0d:
            dev->pci_conf[addr] = val & 0xf8;
            break;

        case 0x12:
            dev->pci_conf[0x12] = (val & 0xc0);
            ali1541_mask_bar(dev);
            break;
        case 0x13:
            dev->pci_conf[0x13] = val;
            ali1541_mask_bar(dev);
            break;

        case 0x2c: /* Subsystem Vendor ID */
        case 0x2d:
        case 0x2e:
        case 0x2f:
            if (dev->pci_conf[0x90] & 0x01)
                dev->pci_conf[addr] = val;
            break;

        case 0x34:
            if (dev->pci_conf[0x90] & 0x02)
                dev->pci_conf[addr] = val;
            break;

        case 0x40:
            dev->pci_conf[addr] = val & 0x7f;
            break;

        case 0x41:
            dev->pci_conf[addr] = val & 0x7f;
            break;

        case 0x42: /* L2 Cache */
            dev->pci_conf[addr]   = val;
            cpu_cache_ext_enabled = !!(val & 1);
            cpu_update_waitstates();
            break;

        case 0x43: /* PLCTL-Pipe Line Control */
            dev->pci_conf[addr] = val & 0xf7;
            break;

        case 0x44:
            dev->pci_conf[addr] = val;
            break;
        case 0x45:
            dev->pci_conf[addr] = val;
            break;
        case 0x46:
            dev->pci_conf[addr] = val & 0xf0;
            break;
        case 0x47:
            dev->pci_conf[addr] = val;
            break;

        case 0x48:
            dev->pci_conf[addr] = val;
            break;
        case 0x49:
            dev->pci_conf[addr] = val;
            break;

        case 0x4a:
            dev->pci_conf[addr] = val & 0xf8;
            break;

        case 0x4b:
            dev->pci_conf[addr] = val;
            break;

        case 0x4c:
            dev->pci_conf[addr] = val;
            break;
        case 0x4d:
            dev->pci_conf[addr] = val;
            break;

        case 0x4e:
            dev->pci_conf[addr] = val;
            break;
        case 0x4f:
            dev->pci_conf[addr] = val;
            break;

        case 0x50:
            dev->pci_conf[addr] = val & 0x71;
            break;

        case 0x51:
            dev->pci_conf[addr] = val;
            break;

        case 0x52:
            dev->pci_conf[addr] = val;
            break;

        case 0x53:
            dev->pci_conf[addr] = val;
            break;

        case 0x54:
            dev->pci_conf[addr] = val & 0x3c;

            if (mem_size > 0xe00000)
                mem_set_mem_state_both(0xe00000, 0x100000, (val & 0x20) ? (MEM_READ_EXTANY | MEM_WRITE_EXTANY) : (MEM_READ_INTERNAL | MEM_WRITE_INTERNAL));

            if (mem_size > 0xf00000)
                mem_set_mem_state_both(0xf00000, 0x100000, (val & 0x10) ? (MEM_READ_EXTANY | MEM_WRITE_EXTANY) : (MEM_READ_INTERNAL | MEM_WRITE_INTERNAL));

            mem_set_mem_state_both(0xa0000, 0x20000, (val & 8) ? (MEM_READ_INTERNAL | MEM_WRITE_INTERNAL) : (MEM_READ_EXTANY | MEM_WRITE_EXTANY));
            mem_set_mem_state_both(0x80000, 0x20000, (val & 4) ? (MEM_READ_EXTANY | MEM_WRITE_EXTANY) : (MEM_READ_INTERNAL | MEM_WRITE_INTERNAL));

            flushmmucache_nopc();
            break;

        case 0x55: /* SMRAM */
            dev->pci_conf[addr] = val & 0x1f;
            ali1541_smram_recalc(val, dev);
            break;

        case 0x56 ... 0x59: /* Shadow RAM */
            dev->pci_conf[addr] = val;
            ali1541_shadow_recalc(val, dev);
            break;

        case 0x5a:
        case 0x5b:
            dev->pci_conf[addr] = val;
            break;

        case 0x5c:
            dev->pci_conf[addr] = val;
            break;

        case 0x5d:
            dev->pci_conf[addr] = val & 0x17;
            break;

        case 0x5e:
            dev->pci_conf[addr] = val;
            break;

        case 0x5f:
            dev->pci_conf[addr] = val & 0xc1;
            break;

        case 0x60 ... 0x6f: /* DRB's */
            dev->pci_conf[addr] = val;
            spd_write_drbs_interleaved(dev->pci_conf, 0x60, 0x6f, 1);
            break;

        case 0x70:
            dev->pci_conf[addr] = val;
            break;

        case 0x71:
            dev->pci_conf[addr] = val;
            break;

        case 0x72:
            dev->pci_conf[addr] = val & 0xc7;
            break;

        case 0x73:
            dev->pci_conf[addr] = val & 0x1f;
            break;

        case 0x84:
        case 0x85:
            dev->pci_conf[addr] = val;
            break;

        case 0x86:
            dev->pci_conf[addr] = val & 0x0f;
            break;

        case 0x87: /* H2PO */
            dev->pci_conf[addr] = val;
            /* Find where the Shut-down Special cycle is initiated. */
#if 0
            if (!(val & 0x20))
                outb(0x92, 0x01);
#endif
            break;

        case 0x88:
            dev->pci_conf[addr] = val;
            break;

        case 0x89:
            dev->pci_conf[addr] = val;
            break;

        case 0x8a:
            dev->pci_conf[addr] = val;
            break;

        case 0x8b:
            dev->pci_conf[addr] = val & 0x3f;
            break;

        case 0x8c:
            dev->pci_conf[addr] = val;
            break;

        case 0x8d:
            dev->pci_conf[addr] = val;
            break;

        case 0x8e:
            dev->pci_conf[addr] = val;
            break;

        case 0x8f:
            dev->pci_conf[addr] = val;
            break;

        case 0x90:
            dev->pci_conf[addr] = val;
            pci_bridge_set_ctl(dev->agp_bridge, val);
            break;

        case 0x91:
            dev->pci_conf[addr] = val;
            break;

        case 0xb4:
            if (dev->pci_conf[0x90] & 0x01)
                dev->pci_conf[addr] = val & 0x03;
            break;
        case 0xb5:
            if (dev->pci_conf[0x90] & 0x01)
                dev->pci_conf[addr] = val & 0x02;
            break;
        case 0xb7:
            if (dev->pci_conf[0x90] & 0x01)
                dev->pci_conf[addr] = val;
            break;

        case 0xb8:
            dev->pci_conf[addr] = val & 0x03;
            break;
        case 0xb9:
            dev->pci_conf[addr] = val & 0x03;
            break;
        case 0xbb:
            dev->pci_conf[addr] = val;
            break;

        case 0xbc:
            dev->pci_conf[addr] = val & 0x0f;
            ali1541_mask_bar(dev);
            break;
        case 0xbd:
            dev->pci_conf[addr] = val & 0xf0;
            break;
        case 0xbe:
        case 0xbf:
            dev->pci_conf[addr] = val;
            break;

        case 0xc0:
            dev->pci_conf[addr] = val & 0x90;
            break;
        case 0xc1:
        case 0xc2:
        case 0xc3:
            dev->pci_conf[addr] = val;
            break;

        case 0xc8:
        case 0xc9:
            dev->pci_conf[addr] = val;
            break;

        case 0xd1:
            dev->pci_conf[addr] = val & 0xf1;
            break;
        case 0xd2:
        case 0xd3:
            dev->pci_conf[addr] = val;
            break;

        case 0xe0:
        case 0xe1:
            if (dev->pci_conf[0x90] & 0x20)
                dev->pci_conf[addr] = val;
            break;
        case 0xe2:
            if (dev->pci_conf[0x90] & 0x20)
                dev->pci_conf[addr] = val & 0x3f;
            break;
        case 0xe3:
            if (dev->pci_conf[0x90] & 0x20)
                dev->pci_conf[addr] = val & 0xfe;
            break;

        case 0xe4:
            if (dev->pci_conf[0x90] & 0x20)
                dev->pci_conf[addr] = val & 0x03;
            break;
        case 0xe5:
            if (dev->pci_conf[0x90] & 0x20)
                dev->pci_conf[addr] = val;
            break;

        case 0xe6:
            if (dev->pci_conf[0x90] & 0x20)
                dev->pci_conf[addr] = val & 0xc0;
            break;

        case 0xe7:
            if (dev->pci_conf[0x90] & 0x20)
                dev->pci_conf[addr] = val;
            break;

        case 0xe8:
        case 0xe9:
            if (dev->pci_conf[0x90] & 0x04)
                dev->pci_conf[addr] = val;
            break;

        case 0xea:
            dev->pci_conf[addr] = val & 0xcf;
            break;

        case 0xeb:
            dev->pci_conf[addr] = val & 0xcf;
            break;

        case 0xec:
            dev->pci_conf[addr] = val & 0x3f;
            break;

        case 0xed:
            dev->pci_conf[addr] = val;
            break;

        case 0xee:
            dev->pci_conf[addr] = val & 0x3e;
            break;
        case 0xef:
            dev->pci_conf[addr] = val;
            break;

        case 0xf3:
            dev->pci_conf[addr] = val & 0x08;
            break;

        case 0xf5:
            dev->pci_conf[addr] = val;
            break;

        case 0xf6:
            dev->pci_conf[addr] = val;
            break;

        case 0xf7:
            dev->pci_conf[addr] = val & 0x43;
            break;

        default:
            break;
    }
}

static uint8_t
ali1541_read(UNUSED(int func), int addr, void *priv)
{
    const ali1541_t *dev = (ali1541_t *) priv;
    uint8_t          ret = 0xff;

    ret = dev->pci_conf[addr];

    return ret;
}

static void
ali1541_reset(void *priv)
{
    ali1541_t *dev = (ali1541_t *) priv;

    /* Default Registers */
    dev->pci_conf[0x00] = 0xb9;
    dev->pci_conf[0x01] = 0x10;
    dev->pci_conf[0x02] = 0x41;
    dev->pci_conf[0x03] = 0x15;
    dev->pci_conf[0x04] = 0x06;
    dev->pci_conf[0x05] = 0x00;
    dev->pci_conf[0x06] = 0x10;
    dev->pci_conf[0x07] = 0x04;
    dev->pci_conf[0x08] = 0x00;
    dev->pci_conf[0x09] = 0x00;
    dev->pci_conf[0x0a] = 0x00;
    dev->pci_conf[0x0b] = 0x06;
    dev->pci_conf[0x0c] = 0x00;
    dev->pci_conf[0x0d] = 0x20;
    dev->pci_conf[0x0e] = 0x00;
    dev->pci_conf[0x0f] = 0x00;
    dev->pci_conf[0x2c] = 0xb9;
    dev->pci_conf[0x2d] = 0x10;
    dev->pci_conf[0x2e] = 0x41;
    dev->pci_conf[0x2f] = 0x15;
    dev->pci_conf[0x34] = 0xb0;
    dev->pci_conf[0x89] = 0x20;
    dev->pci_conf[0x8a] = 0x20;
    dev->pci_conf[0x91] = 0x13;
    dev->pci_conf[0xb0] = 0x02;
    dev->pci_conf[0xb1] = 0xe0;
    dev->pci_conf[0xb2] = 0x10;
    dev->pci_conf[0xb4] = 0x03;
    dev->pci_conf[0xb5] = 0x02;
    dev->pci_conf[0xb7] = 0x1c;
    dev->pci_conf[0xc8] = 0xbf;
    dev->pci_conf[0xc9] = 0x0a;
    dev->pci_conf[0xe0] = 0x01;

    cpu_cache_int_enabled = 1;
    ali1541_write(0, 0x42, 0x00, dev);

    ali1541_write(0, 0x54, 0x00, dev);
    ali1541_write(0, 0x55, 0x00, dev);

    for (uint8_t i = 0; i < 4; i++)
        ali1541_write(0, 0x56 + i, 0x00, dev);

    ali1541_write(0, 0x60, 0x07, dev);
    ali1541_write(0, 0x61, 0x40, dev);

    for (uint8_t i = 0; i < 14; i += 2) {
        ali1541_write(0, 0x62 + i, 0x00, dev);
        ali1541_write(0, 0x63 + i, 0x00, dev);
    }
}

static void
ali1541_close(void *priv)
{
    ali1541_t *dev = (ali1541_t *) priv;

    smram_del(dev->smram);
    free(dev);
}

static void *
ali1541_init(UNUSED(const device_t *info))
{
    ali1541_t *dev = (ali1541_t *) calloc(1, sizeof(ali1541_t));

    pci_add_card(PCI_ADD_NORTHBRIDGE, ali1541_read, ali1541_write, dev, &dev->pci_slot);

    dev->smram = smram_add();

    ali1541_reset(dev);

    dev->agp_bridge = device_add(&ali5243_agp_device);

    return dev;
}

const device_t ali1541_device = {
    .name          = "ALi M1541 CPU-to-PCI Bridge",
    .internal_name = "ali1541",
    .flags         = DEVICE_PCI,
    .local         = 0,
    .init          = ali1541_init,
    .close         = ali1541_close,
    .reset         = ali1541_reset,
    .available     = NULL,
    .speed_changed = NULL,
    .force_redraw  = NULL,
    .config        = NULL
};
