/*
 * 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.
 *
 *		Universal Serial Bus emulation (currently dummy UHCI and
 *		OHCI).
 *
 *
 *
 * Authors:	Miran Grca, <mgrca8@gmail.com>
 *
 *		Copyright 2020 Miran Grca.
 */
#include <stdarg.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>
#define HAVE_STDARG_H
#include <86box/86box.h>
#include <86box/device.h>
#include <86box/io.h>
#include <86box/mem.h>
#include <86box/usb.h>
#include "cpu.h"


#ifdef ENABLE_USB_LOG
int usb_do_log = ENABLE_USB_LOG;


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

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


static uint8_t
uhci_reg_read(uint16_t addr, void *p)
{
    usb_t *dev = (usb_t *) p;
    uint8_t ret, *regs = dev->uhci_io;

    addr &= 0x0000001f;

    ret = regs[addr];

    return ret;
}


static void
uhci_reg_write(uint16_t addr, uint8_t val, void *p)
{
    usb_t *dev = (usb_t *) p;
    uint8_t *regs = dev->uhci_io;

    addr &= 0x0000001f;

    switch (addr) {
	case 0x02:
		regs[0x02] &= ~(val & 0x3f);
		break;
	case 0x04:
		regs[0x04] = (val & 0x0f);
		break;
	case 0x09:
		regs[0x09] = (val & 0xf0);
		break;
	case 0x0a: case 0x0b:
		regs[addr] = val;
		break;
	case 0x0c:
		regs[0x0c] = (val & 0x7f);
		break;
    }
}


static void
uhci_reg_writew(uint16_t addr, uint16_t val, void *p)
{
    usb_t *dev = (usb_t *) p;
    uint16_t *regs = (uint16_t *) dev->uhci_io;

    addr &= 0x0000001f;

    switch (addr) {
	case 0x00:
		if ((val & 0x0001) && !(regs[0x00] & 0x0001))
			regs[0x01] &= ~0x20;
		else if (!(val & 0x0001))
			regs[0x01] |= 0x20;
		regs[0x00] = (val & 0x00ff);
		break;
	case 0x06:
		regs[0x03] = (val & 0x07ff);
		break;
	case 0x10: case 0x12:
		regs[addr >> 1] = ((regs[addr >> 1] & 0xedbb) | (val & 0x1244)) & ~(val & 0x080a);
		break;
	default:
		uhci_reg_write(addr, val & 0xff, p);
		uhci_reg_write(addr + 1, (val >> 8) & 0xff, p);
		break;
    }
}


void
uhci_update_io_mapping(usb_t *dev, uint8_t base_l, uint8_t base_h, int enable)
{
    if (dev->uhci_enable && (dev->uhci_io_base != 0x0000))
	io_removehandler(dev->uhci_io_base, 0x20, uhci_reg_read, NULL, NULL, uhci_reg_write, uhci_reg_writew, NULL, dev);

    dev->uhci_io_base = base_l | (base_h << 8);
    dev->uhci_enable = enable;

    if (dev->uhci_enable && (dev->uhci_io_base != 0x0000))
	io_sethandler(dev->uhci_io_base, 0x20, uhci_reg_read, NULL, NULL, uhci_reg_write, uhci_reg_writew, NULL, dev);
}


static uint8_t
ohci_mmio_read(uint32_t addr, void *p)
{
    usb_t *dev = (usb_t *) p;
    uint8_t ret = 0x00;

    addr &= 0x00000fff;

    ret = dev->ohci_mmio[addr];

    if (addr == 0x101)
	ret = (ret & 0xfe) | (!!mem_a20_key);

    return ret;
}


static void
ohci_mmio_write(uint32_t addr, uint8_t val, void *p)
{
    usb_t *dev = (usb_t *) p;
    uint8_t old;

    addr &= 0x00000fff;

    switch (addr) {
	case 0x04:
		if ((val & 0xc0) == 0x00) {
			/* UsbReset */
			dev->ohci_mmio[0x56] = dev->ohci_mmio[0x5a] = 0x16;
		}
		break;
    	case 0x08: /* HCCOMMANDSTATUS */
    		/* bit OwnershipChangeRequest triggers an ownership change (SMM <-> OS) */
    		if (val & 0x08) {
    			dev->ohci_mmio[0x0f] = 0x40;
			if ((dev->ohci_mmio[0x13] & 0xc0) == 0xc0)
				smi_line = 1;
		}

    		/* bit HostControllerReset must be cleared for the controller to be seen as initialized */
		if (val & 0x01) {
			memset(dev->ohci_mmio, 0x00, 4096);
			dev->ohci_mmio[0x00] = 0x10;
			dev->ohci_mmio[0x01] = 0x01;
			dev->ohci_mmio[0x48] = 0x02;
	    		val &= ~0x01;
		}
    		break;
	case 0x0c:
		dev->ohci_mmio[addr] &= ~(val & 0x7f);
		return;
	case 0x0d: case 0x0e:
		return;
	case 0x0f:
		dev->ohci_mmio[addr] &= ~(val & 0x40);
		return;
	case 0x3b:
		dev->ohci_mmio[addr] = (val & 0x80);
		return;
	case 0x39: case 0x41:
		dev->ohci_mmio[addr] = (val & 0x3f);
		return;
	case 0x45:
		dev->ohci_mmio[addr] = (val & 0x0f);
		return;
	case 0x3a:
	case 0x3e: case 0x3f: case 0x42: case 0x43:
	case 0x46: case 0x47: case 0x48: case 0x4a:
		return;
	case 0x49:
		dev->ohci_mmio[addr] = (val & 0x1b);
		if (val & 0x02) {
			dev->ohci_mmio[0x55] |= 0x01;
			dev->ohci_mmio[0x59] |= 0x01;
		}
		return;
	case 0x4b:
		dev->ohci_mmio[addr] = (val & 0x03);
		return;
	case 0x4c: case 0x4e:
		dev->ohci_mmio[addr] = (val & 0x06);
		if ((addr == 0x4c) && !(val & 0x04)) {
			if (!(dev->ohci_mmio[0x58] & 0x01))
				dev->ohci_mmio[0x5a] |= 0x01;
			dev->ohci_mmio[0x58] |= 0x01;
		} if ((addr == 0x4c) && !(val & 0x02)) {
			if (!(dev->ohci_mmio[0x54] & 0x01))
				dev->ohci_mmio[0x56] |= 0x01;
			dev->ohci_mmio[0x54] |= 0x01;
		}
		return;
	case 0x4d: case 0x4f:
		return;
	case 0x50:
		if (val & 0x01) {
			if ((dev->ohci_mmio[0x49] & 0x03) == 0x00) {
				dev->ohci_mmio[0x55] &= ~0x01;
				dev->ohci_mmio[0x54] &= ~0x17;
				dev->ohci_mmio[0x56] &= ~0x17;
				dev->ohci_mmio[0x59] &= ~0x01;
				dev->ohci_mmio[0x58] &= ~0x17;
				dev->ohci_mmio[0x5a] &= ~0x17;
			} else if ((dev->ohci_mmio[0x49] & 0x03) == 0x01) {
				if (!(dev->ohci_mmio[0x4e] & 0x02)) {
					dev->ohci_mmio[0x55] &= ~0x01;
					dev->ohci_mmio[0x54] &= ~0x17;
					dev->ohci_mmio[0x56] &= ~0x17;
				}
				if (!(dev->ohci_mmio[0x4e] & 0x04)) {
					dev->ohci_mmio[0x59] &= ~0x01;
					dev->ohci_mmio[0x58] &= ~0x17;
					dev->ohci_mmio[0x5a] &= ~0x17;
				}
			}
		}
		return;
	case 0x51:
		if (val & 0x80)
			dev->ohci_mmio[addr] |= 0x80;
		return;
	case 0x52:
		dev->ohci_mmio[addr] &= ~(val & 0x02);
		if (val & 0x01) {
			if ((dev->ohci_mmio[0x49] & 0x03) == 0x00) {
				dev->ohci_mmio[0x55] |= 0x01;
				dev->ohci_mmio[0x59] |= 0x01;
			} else if ((dev->ohci_mmio[0x49] & 0x03) == 0x01) {
				if (!(dev->ohci_mmio[0x4e] & 0x02))
					dev->ohci_mmio[0x55] |= 0x01;
				if (!(dev->ohci_mmio[0x4e] & 0x04))
					dev->ohci_mmio[0x59] |= 0x01;
			}
		}
		return;
	case 0x53:
		if (val & 0x80)
			dev->ohci_mmio[0x51] &= ~0x80;
		return;
	case 0x54: case 0x58:
		old = dev->ohci_mmio[addr];

		if (val & 0x10) {
			if (old & 0x01) {
				dev->ohci_mmio[addr] |= 0x10;
				/* TODO: The clear should be on a 10 ms timer. */
				dev->ohci_mmio[addr] &= ~0x10;
				dev->ohci_mmio[addr + 2] |= 0x10;
			} else
				dev->ohci_mmio[addr + 2] |= 0x01;
		}
		if (val & 0x08)
			dev->ohci_mmio[addr] &= ~0x04;
		if (val & 0x04)
			dev->ohci_mmio[addr] |= 0x04;
		if (val & 0x02) {
			if (old & 0x01)
				dev->ohci_mmio[addr] |= 0x02;
			else
				dev->ohci_mmio[addr + 2] |= 0x01;
		}
		if (val & 0x01) {
			if (old & 0x01)
				dev->ohci_mmio[addr] &= ~0x02;
			else
				dev->ohci_mmio[addr + 2] |= 0x01;
		}

		if (!(dev->ohci_mmio[addr] & 0x04) && (old & 0x04))
			dev->ohci_mmio[addr + 2] |= 0x04;
		/* if (!(dev->ohci_mmio[addr] & 0x02))
			dev->ohci_mmio[addr + 2] |= 0x02; */
		return;
	case 0x55:
		if ((val & 0x02) && ((dev->ohci_mmio[0x49] & 0x03) == 0x00) && (dev->ohci_mmio[0x4e] & 0x02)) {
			dev->ohci_mmio[addr] &= ~0x01;
			dev->ohci_mmio[0x54] &= ~0x17;
			dev->ohci_mmio[0x56] &= ~0x17;
		} if ((val & 0x01) && ((dev->ohci_mmio[0x49] & 0x03) == 0x00) && (dev->ohci_mmio[0x4e] & 0x02)) {
			dev->ohci_mmio[addr] |= 0x01;
			dev->ohci_mmio[0x58] &= ~0x17;
			dev->ohci_mmio[0x5a] &= ~0x17;
		}
		return;
	case 0x59:
		if ((val & 0x02) && ((dev->ohci_mmio[0x49] & 0x03) == 0x00) && (dev->ohci_mmio[0x4e] & 0x04))
			dev->ohci_mmio[addr] &= ~0x01;
		if ((val & 0x01) && ((dev->ohci_mmio[0x49] & 0x03) == 0x00) && (dev->ohci_mmio[0x4e] & 0x04))
			dev->ohci_mmio[addr] |= 0x01;
		return;
	case 0x56: case 0x5a:
		dev->ohci_mmio[addr] &= ~(val & 0x1f);
		return;
	case 0x57: case 0x5b:
		return;
    }

    dev->ohci_mmio[addr] = val;
}


void
ohci_update_mem_mapping(usb_t *dev, uint8_t base1, uint8_t base2, uint8_t base3, int enable)
{
    if (dev->ohci_enable && (dev->ohci_mem_base != 0x00000000))
	mem_mapping_disable(&dev->ohci_mmio_mapping);

    dev->ohci_mem_base = ((base1 << 8) | (base2 << 16) | (base3 << 24)) & 0xfffff000;
    dev->ohci_enable = enable;

    if (dev->ohci_enable && (dev->ohci_mem_base != 0x00000000))
    	mem_mapping_set_addr(&dev->ohci_mmio_mapping, dev->ohci_mem_base, 0x1000);
}


static void
usb_reset(void *priv)
{
    usb_t *dev = (usb_t *) priv;

    memset(dev->uhci_io, 0x00, 128);
    dev->uhci_io[0x0c] = 0x40;
    dev->uhci_io[0x10] = dev->uhci_io[0x12] = 0x80;

    memset(dev->ohci_mmio, 0x00, 4096);
    dev->ohci_mmio[0x00] = 0x10;
    dev->ohci_mmio[0x01] = 0x01;
    dev->ohci_mmio[0x48] = 0x02;

    io_removehandler(dev->uhci_io_base, 0x20, uhci_reg_read, NULL, NULL, uhci_reg_write, uhci_reg_writew, NULL, dev);
    dev->uhci_enable = 0;

    mem_mapping_disable(&dev->ohci_mmio_mapping);
    dev->ohci_enable = 0;
}


static void
usb_close(void *priv)
{
    usb_t *dev = (usb_t *) priv;

    free(dev);
}


static void *
usb_init(const device_t *info)
{
    usb_t *dev;

    dev = (usb_t *)malloc(sizeof(usb_t));
    if (dev == NULL) return(NULL);
    memset(dev, 0x00, sizeof(usb_t));

    memset(dev->uhci_io, 0x00, 128);
    dev->uhci_io[0x0c] = 0x40;
    dev->uhci_io[0x10] = dev->uhci_io[0x12] = 0x80;

    memset(dev->ohci_mmio, 0x00, 4096);
    dev->ohci_mmio[0x00] = 0x10;
    dev->ohci_mmio[0x01] = 0x01;
    dev->ohci_mmio[0x48] = 0x02;

    mem_mapping_add(&dev->ohci_mmio_mapping, 0, 0,
		    ohci_mmio_read,  NULL, NULL,
		    ohci_mmio_write, NULL, NULL,
		    NULL, MEM_MAPPING_EXTERNAL, dev);
    usb_reset(dev);

    return dev;
}


const device_t usb_device =
{
    "Universal Serial Bus",
    DEVICE_PCI,
    0,
    usb_init, 
    usb_close, 
    usb_reset,
    { NULL },
    NULL,
    NULL,
    NULL
};