/*
 * 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.
 *
 *		Emulation of the NatSemi PC87332 Super I/O chip.
 *
 *
 *
 * Author:	Miran Grca, <mgrca8@gmail.com>
 *		Copyright 2020 Miran Grca.
 */
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>
#include <86box/86box.h>
#include <86box/io.h>
#include <86box/timer.h>
#include <86box/device.h>
#include <86box/lpt.h>
#include <86box/mem.h>
#include <86box/nvr.h>
#include <86box/pci.h>
#include <86box/rom.h>
#include <86box/serial.h>
#include <86box/hdc.h>
#include <86box/hdc_ide.h>
#include <86box/fdd.h>
#include <86box/fdc.h>
#include <86box/sio.h>


typedef struct {
    uint8_t tries, has_ide,
	    fdc_on, regs[15];
    int cur_reg;
    fdc_t *fdc;
    serial_t *uart[2];
} pc87332_t;


static void
lpt1_handler(pc87332_t *dev)
{
    int temp;
    uint16_t lpt_port = 0x378;
    uint8_t lpt_irq = 5;

    temp = dev->regs[0x01] & 3;

    switch (temp) {
	case 0:
		lpt_port = 0x378;
		lpt_irq = (dev->regs[0x02] & 0x08) ? 7 : 5;
		break;
	case 1:
		lpt_port = 0x3bc;
		lpt_irq = 7;
		break;
	case 2:
		lpt_port = 0x278;
		lpt_irq = 5;
		break;
	case 3:
		lpt_port = 0x000;
		lpt_irq = 0xff;
		break;
    }

    if (lpt_port)
	lpt1_init(lpt_port);

    lpt1_irq(lpt_irq);
}


static void
serial_handler(pc87332_t *dev, int uart)
{
    int temp;

    temp = (dev->regs[1] >> (2 << uart)) & 3;

    switch (temp) {
	case 0:
		serial_setup(dev->uart[uart], SERIAL1_ADDR, 4);
		break;
	case 1:
		serial_setup(dev->uart[uart], SERIAL2_ADDR, 3);
		break;
	case 2:
		switch ((dev->regs[1] >> 6) & 3) {
			case 0:
				serial_setup(dev->uart[uart], 0x3e8, 4);
				break;
			case 1:
				serial_setup(dev->uart[uart], 0x338, 4);
				break;
			case 2:
				serial_setup(dev->uart[uart], 0x2e8, 4);
				break;
			case 3:
				serial_setup(dev->uart[uart], 0x220, 4);
				break;
		}
		break;
	case 3:
		switch ((dev->regs[1] >> 6) & 3) {
			case 0:
				serial_setup(dev->uart[uart], 0x2e8, 3);
				break;
			case 1:
				serial_setup(dev->uart[uart], 0x238, 3);
				break;
			case 2:
				serial_setup(dev->uart[uart], 0x2e0, 3);
				break;
			case 3:
				serial_setup(dev->uart[uart], 0x228, 3);
				break;
		}
		break;
    }
}


static void
ide_handler(pc87332_t *dev)
{
    /* TODO: Make an ide_disable(channel) and ide_enable(channel) so we can simplify this. */
    if (dev->has_ide == 2) {
	ide_sec_disable();
	ide_set_base(1, (dev->regs[0x00] & 0x80) ? 0x170 : 0x1f0);
	ide_set_side(1, (dev->regs[0x00] & 0x80) ? 0x376 : 0x3f6);
	if (dev->regs[0x00] & 0x40)
		ide_sec_enable();
    } else if (dev->has_ide == 1) {
	ide_pri_disable();
	ide_set_base(0, (dev->regs[0x00] & 0x80) ? 0x170 : 0x1f0);
	ide_set_side(0, (dev->regs[0x00] & 0x80) ? 0x376 : 0x3f6);
	if (dev->regs[0x00] & 0x40)
		ide_pri_enable();
    }
}


static void
pc87332_write(uint16_t port, uint8_t val, void *priv)
{
    pc87332_t *dev = (pc87332_t *) priv;
    uint8_t index, valxor;

    index = (port & 1) ? 0 : 1;

    if (index) {
	dev->cur_reg = val & 0x1f;
	dev->tries = 0;
	return;
    } else {
	if (dev->tries) {
		valxor = val ^ dev->regs[dev->cur_reg];
		dev->tries = 0;
		if ((dev->cur_reg <= 14) && (dev->cur_reg != 8))
			dev->regs[dev->cur_reg] = val;
		else
			return;
	} else {
		dev->tries++;
		return;
	}
    }

    switch(dev->cur_reg) {
	case 0:
		if (valxor & 1) {
			lpt1_remove();
			if ((val & 1) && !(dev->regs[2] & 1))
				lpt1_handler(dev);
		}
		if (valxor & 2) {
			serial_remove(dev->uart[0]);
			if ((val & 2) && !(dev->regs[2] & 1))
				serial_handler(dev, 0);
		}
		if (valxor & 4) {
			serial_remove(dev->uart[1]);
			if ((val & 4) && !(dev->regs[2] & 1))
				serial_handler(dev, 1);
		}
		if (valxor & 0x28) {
			fdc_remove(dev->fdc);
			if ((val & 8) && !(dev->regs[2] & 1))
				fdc_set_base(dev->fdc, (val & 0x20) ? 0x370 : 0x3f0);
		}
		if (dev->has_ide && (valxor & 0xc0))
			ide_handler(dev);
		break;
	case 1:
		if (valxor & 3) {
			lpt1_remove();
			if ((dev->regs[0] & 1) && !(dev->regs[2] & 1))
				lpt1_handler(dev);
		}
		if (valxor & 0xcc) {
			serial_remove(dev->uart[0]);
			if ((dev->regs[0] & 2) && !(dev->regs[2] & 1))
				serial_handler(dev, 0);
		}
		if (valxor & 0xf0) {
			serial_remove(dev->uart[1]);
			if ((dev->regs[0] & 4) && !(dev->regs[2] & 1))
				serial_handler(dev, 1);
		}
		break;
	case 2:
		if (valxor & 1) {
			lpt1_remove();
			serial_remove(dev->uart[0]);
			serial_remove(dev->uart[1]);
			fdc_remove(dev->fdc);

			if (!(val & 1)) {
				if (dev->regs[0] & 1)
					lpt1_handler(dev);
				if (dev->regs[0] & 2)
					serial_handler(dev, 0);
				if (dev->regs[0] & 4)
					serial_handler(dev, 1);
				if (dev->regs[0] & 8)
					fdc_set_base(dev->fdc, (dev->regs[0] & 0x20) ? 0x370 : 0x3f0);
			}
		}
		if (valxor & 8) {
			lpt1_remove();
			if ((dev->regs[0] & 1) && !(dev->regs[2] & 1))
				lpt1_handler(dev);
		}
		break;
    }
}


uint8_t
pc87332_read(uint16_t port, void *priv)
{
    pc87332_t *dev = (pc87332_t *) priv;
    uint8_t ret = 0xff, index;

    index = (port & 1) ? 0 : 1;

    dev->tries = 0;

    if (index)
	ret = dev->cur_reg & 0x1f;
    else {
	if (dev->cur_reg == 8)
		ret = 0x10;
	else if (dev->cur_reg < 14)
		ret = dev->regs[dev->cur_reg];
    }

    return ret;
}


void
pc87332_reset(pc87332_t *dev)
{
    memset(dev->regs, 0, 15);

    dev->regs[0x00] = dev->fdc_on ? 0x4f : 0x07;
    if (dev->has_ide == 2)
	dev->regs[0x00] |= 0x80;
    dev->regs[0x01] = 0x10;
    dev->regs[0x03] = 0x01;
    dev->regs[0x05] = 0x0D;
    dev->regs[0x08] = 0x70;

    /*
	0 = 360 rpm @ 500 kbps for 3.5"
	1 = Default, 300 rpm @ 500,300,250,1000 kbps for 3.5"
    */
    lpt1_remove();
    lpt1_handler(dev);
    serial_remove(dev->uart[0]);
    serial_remove(dev->uart[1]);
    serial_handler(dev, 0);
    serial_handler(dev, 1);
    fdc_reset(dev->fdc);
    if (!dev->fdc_on)
	fdc_remove(dev->fdc);

    if (dev->has_ide)
	ide_handler(dev);
}


static void
pc87332_close(void *priv)
{
    pc87332_t *dev = (pc87332_t *) priv;

    free(dev);
}


static void *
pc87332_init(const device_t *info)
{
    pc87332_t *dev = (pc87332_t *) malloc(sizeof(pc87332_t));
    memset(dev, 0, sizeof(pc87332_t));

    dev->fdc = device_add(&fdc_at_nsc_device);

    dev->uart[0] = device_add_inst(&ns16550_device, 1);
    dev->uart[1] = device_add_inst(&ns16550_device, 2);

    dev->has_ide = (info->local >> 8) & 0xff;
    dev->fdc_on = (info->local >> 16) & 0xff;
    pc87332_reset(dev);

    if ((info->local & 0xff) == (0x01)) {
	io_sethandler(0x398, 0x0002,
		      pc87332_read, NULL, NULL, pc87332_write, NULL, NULL, dev);
    } else {
	io_sethandler(0x02e, 0x0002,
		      pc87332_read, NULL, NULL, pc87332_write, NULL, NULL, dev);
    }

    return dev;
}


const device_t pc87332_device = {
    "National Semiconductor PC87332 Super I/O",
    "pc87332",
    0,
    0x00,
    pc87332_init, pc87332_close, NULL,
    { NULL }, NULL, NULL,
    NULL
};


const device_t pc87332_398_device = {
    "National Semiconductor PC87332 Super I/O (Port 398h)",
    "pc87332_398",
    0,
    0x01,
    pc87332_init, pc87332_close, NULL,
    { NULL }, NULL, NULL,
    NULL
};


const device_t pc87332_398_ide_device = {
    "National Semiconductor PC87332 Super I/O (Port 398h) (With IDE)",
    "pc87332_398_ide",
    0,
    0x101,
    pc87332_init, pc87332_close, NULL,
    { NULL }, NULL, NULL,
    NULL
};


const device_t pc87332_398_ide_sec_device = {
    "National Semiconductor PC87332 Super I/O (Port 398h) (With Secondary IDE)",
    "pc87332_398_ide_sec",
    0,
    0x201,
    pc87332_init, pc87332_close, NULL,
    { NULL }, NULL, NULL,
    NULL
};


const device_t pc87332_398_ide_fdcon_device = {
    "National Semiconductor PC87332 Super I/O (Port 398h) (With IDE and FDC on)",
    "pc87332_398_ide_fdcon",
    0,
    0x10101,
    pc87332_init, pc87332_close, NULL,
    { NULL }, NULL, NULL,
    NULL
};
