/*
 * ACPI implementation
 *
 * Copyright (c) 2006 Fabrice Bellard
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License version 2 as published by the Free Software Foundation.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include "hw.h"
#include "pc.h"
#include "pci.h"
#include "qemu-timer.h"
#include "sysemu.h"
#include "i2c.h"
#include "smbus.h"

//#define DEBUG

/* i82731AB (PIIX4) compatible power management function */
#define PM_FREQ 3579545

#define ACPI_DBG_IO_ADDR  0xb044

typedef struct PIIX4PMState {
    PCIDevice dev;
    uint16_t pmsts;
    uint16_t pmen;
    uint16_t pmcntrl;
    uint8_t apmc;
    uint8_t apms;
    QEMUTimer *tmr_timer;
    int64_t tmr_overflow_time;
    i2c_bus *smbus;
    uint8_t smb_stat;
    uint8_t smb_ctl;
    uint8_t smb_cmd;
    uint8_t smb_addr;
    uint8_t smb_data0;
    uint8_t smb_data1;
    uint8_t smb_data[32];
    uint8_t smb_index;
    qemu_irq irq;
    int64_t pmtmr;
} PIIX4PMState;

#define RTC_EN (1 << 10)
#define PWRBTN_EN (1 << 8)
#define GBL_EN (1 << 5)
#define TMROF_EN (1 << 0)
#define TIMER_OVERFLOW_CNT (1 << 23)
#define TIMER_MASK 0xffffffLL

#define SCI_EN (1 << 0)

#define SUS_EN (1 << 13)

#define ACPI_ENABLE 0xf1
#define ACPI_DISABLE 0xf0

#define SMBHSTSTS 0x00
#define SMBHSTCNT 0x02
#define SMBHSTCMD 0x03
#define SMBHSTADD 0x04
#define SMBHSTDAT0 0x05
#define SMBHSTDAT1 0x06
#define SMBBLKDAT 0x07

PIIX4PMState *pm_state;

static void update_pmtmr(PIIX4PMState *s)
{
    int64_t pmtmr;

    pmtmr = muldiv64(qemu_get_clock(vm_clock), PM_FREQ, ticks_per_sec)
            & TIMER_MASK;

    if (!(s->pmsts & TMROF_EN)) {
        if ((pmtmr ^ s->pmtmr) & TIMER_OVERFLOW_CNT) {
            s->pmsts |= TMROF_EN;
            if (s->pmen & TMROF_EN)
                qemu_set_irq(s->irq, 1);
        } else {
            /* Calculate when the timer will neet to set
             * the overflow bit again */
            uint64_t delta = TIMER_OVERFLOW_CNT -
                    (pmtmr & (TIMER_OVERFLOW_CNT - 1));

            delta = muldiv64(delta, ticks_per_sec, PM_FREQ);
            qemu_mod_timer(s->tmr_timer, qemu_get_clock(vm_clock) + delta);
        }
    }

    s->pmtmr = pmtmr;
}

static uint32_t get_pmtmr(PIIX4PMState *s)
{
    update_pmtmr(s);
    return s->pmtmr & TIMER_MASK;
}


static int get_pmsts(PIIX4PMState *s)
{
    /* Just increase the accurancy by double computing the timer value */
    update_pmtmr(s);

    return s->pmsts;
}

static void pm_update_sci(PIIX4PMState *s)
{
    int sci_level;

    sci_level = (((s->pmsts & s->pmen) & 
                   (RTC_EN | PWRBTN_EN | GBL_EN | TMROF_EN)) != 0);
    if (!sci_level)
        qemu_set_irq(s->irq, sci_level);
}

static void pm_tmr_timer(void *opaque)
{
    PIIX4PMState *s = opaque;
    update_pmtmr(s);
}

static void pm_ioport_writew(void *opaque, uint32_t addr, uint32_t val)
{
    PIIX4PMState *s = opaque;
    addr &= 0x3f;
    switch(addr) {
    case 0x00:
        s->pmsts &= ~val;
        update_pmtmr(s);
        pm_update_sci(s);
        break;
    case 0x02:
        s->pmen = val;
        pm_update_sci(s);
        break;
    case 0x04:
        {
            int sus_typ;
            s->pmcntrl = val & ~(SUS_EN);
            if (val & SUS_EN) {
                /* change suspend type */
                sus_typ = (val >> 10) & 3;
                switch(sus_typ) {
                case 0: /* soft power off */
                    qemu_system_shutdown_request();
                    break;
                default:
                    break;
                }
            }
        }
        break;
    default:
        break;
    }
#ifdef DEBUG
    printf("PM writew port=0x%04x val=0x%04x\n", addr, val);
#endif
}

static uint32_t pm_ioport_readw(void *opaque, uint32_t addr)
{
    PIIX4PMState *s = opaque;
    uint32_t val;

    addr &= 0x3f;
    switch(addr) {
    case 0x00:
        val = get_pmsts(s);
        break;
    case 0x02:
        val = s->pmen;
        break;
    case 0x04:
        val = s->pmcntrl;
        break;
    default:
        val = 0;
        break;
    }
#ifdef DEBUG
    printf("PM readw port=0x%04x val=0x%04x\n", addr, val);
#endif
    return val;
}

static void pm_ioport_writel(void *opaque, uint32_t addr, uint32_t val)
{
    //    PIIX4PMState *s = opaque;
    addr &= 0x3f;
#ifdef DEBUG
    printf("PM writel port=0x%04x val=0x%08x\n", addr, val);
#endif
}

static uint32_t pm_ioport_readl(void *opaque, uint32_t addr)
{
    PIIX4PMState *s = opaque;
    uint32_t val;

    addr &= 0x3f;
    switch(addr) {
    case 0x08:
        val = get_pmtmr(s);
        break;
    default:
        val = 0;
        break;
    }
#ifdef DEBUG
    printf("PM readl port=0x%04x val=0x%08x\n", addr, val);
#endif
    return val;
}

static void pm_smi_writeb(void *opaque, uint32_t addr, uint32_t val)
{
    PIIX4PMState *s = opaque;
    addr &= 1;
#ifdef DEBUG
    printf("pm_smi_writeb addr=0x%x val=0x%02x\n", addr, val);
#endif
    if (addr == 0) {
        s->apmc = val;

        /* ACPI specs 3.0, 4.7.2.5 */
        if (val == ACPI_ENABLE) {
            s->pmcntrl |= SCI_EN;
        } else if (val == ACPI_DISABLE) {
            s->pmcntrl &= ~SCI_EN;
        }

        if (s->dev.config[0x5b] & (1 << 1)) {
            cpu_interrupt(first_cpu, CPU_INTERRUPT_SMI);
        }
    } else {
        s->apms = val;
    }
}

static uint32_t pm_smi_readb(void *opaque, uint32_t addr)
{
    PIIX4PMState *s = opaque;
    uint32_t val;

    addr &= 1;
    if (addr == 0) {
        val = s->apmc;
    } else {
        val = s->apms;
    }
#ifdef DEBUG
    printf("pm_smi_readb addr=0x%x val=0x%02x\n", addr, val);
#endif
    return val;
}

static void acpi_dbg_writel(void *opaque, uint32_t addr, uint32_t val)
{
#if defined(DEBUG)
    printf("ACPI: DBG: 0x%08x\n", val);
#endif
}

static void smb_transaction(PIIX4PMState *s)
{
    uint8_t prot = (s->smb_ctl >> 2) & 0x07;
    uint8_t read = s->smb_addr & 0x01;
    uint8_t cmd = s->smb_cmd;
    uint8_t addr = s->smb_addr >> 1;
    i2c_bus *bus = s->smbus;

#ifdef DEBUG
    printf("SMBus trans addr=0x%02x prot=0x%02x\n", addr, prot);
#endif
    switch(prot) {
    case 0x0:
        smbus_quick_command(bus, addr, read);
        break;
    case 0x1:
        if (read) {
            s->smb_data0 = smbus_receive_byte(bus, addr);
        } else {
            smbus_send_byte(bus, addr, cmd);
        }
        break;
    case 0x2:
        if (read) {
            s->smb_data0 = smbus_read_byte(bus, addr, cmd);
        } else {
            smbus_write_byte(bus, addr, cmd, s->smb_data0);
        }
        break;
    case 0x3:
        if (read) {
            uint16_t val;
            val = smbus_read_word(bus, addr, cmd);
            s->smb_data0 = val;
            s->smb_data1 = val >> 8;
        } else {
            smbus_write_word(bus, addr, cmd, (s->smb_data1 << 8) | s->smb_data0);
        }
        break;
    case 0x5:
        if (read) {
            s->smb_data0 = smbus_read_block(bus, addr, cmd, s->smb_data);
        } else {
            smbus_write_block(bus, addr, cmd, s->smb_data, s->smb_data0);
        }
        break;
    default:
        goto error;
    }
    return;

  error:
    s->smb_stat |= 0x04;
}

static void smb_ioport_writeb(void *opaque, uint32_t addr, uint32_t val)
{
    PIIX4PMState *s = opaque;
    addr &= 0x3f;
#ifdef DEBUG
    printf("SMB writeb port=0x%04x val=0x%02x\n", addr, val);
#endif
    switch(addr) {
    case SMBHSTSTS:
        s->smb_stat = 0;
        s->smb_index = 0;
        break;
    case SMBHSTCNT:
        s->smb_ctl = val;
        if (val & 0x40)
            smb_transaction(s);
        break;
    case SMBHSTCMD:
        s->smb_cmd = val;
        break;
    case SMBHSTADD:
        s->smb_addr = val;
        break;
    case SMBHSTDAT0:
        s->smb_data0 = val;
        break;
    case SMBHSTDAT1:
        s->smb_data1 = val;
        break;
    case SMBBLKDAT:
        s->smb_data[s->smb_index++] = val;
        if (s->smb_index > 31)
            s->smb_index = 0;
        break;
    default:
        break;
    }
}

static uint32_t smb_ioport_readb(void *opaque, uint32_t addr)
{
    PIIX4PMState *s = opaque;
    uint32_t val;

    addr &= 0x3f;
    switch(addr) {
    case SMBHSTSTS:
        val = s->smb_stat;
        break;
    case SMBHSTCNT:
        s->smb_index = 0;
        val = s->smb_ctl & 0x1f;
        break;
    case SMBHSTCMD:
        val = s->smb_cmd;
        break;
    case SMBHSTADD:
        val = s->smb_addr;
        break;
    case SMBHSTDAT0:
        val = s->smb_data0;
        break;
    case SMBHSTDAT1:
        val = s->smb_data1;
        break;
    case SMBBLKDAT:
        val = s->smb_data[s->smb_index++];
        if (s->smb_index > 31)
            s->smb_index = 0;
        break;
    default:
        val = 0;
        break;
    }
#ifdef DEBUG
    printf("SMB readb port=0x%04x val=0x%02x\n", addr, val);
#endif
    return val;
}

static void pm_io_space_update(PIIX4PMState *s)
{
    uint32_t pm_io_base;

    if (s->dev.config[0x80] & 1) {
        pm_io_base = le32_to_cpu(*(uint32_t *)(s->dev.config + 0x40));
        pm_io_base &= 0xffc0;

        /* XXX: need to improve memory and ioport allocation */
#if defined(DEBUG)
        printf("PM: mapping to 0x%x\n", pm_io_base);
#endif
        register_ioport_write(pm_io_base, 64, 2, pm_ioport_writew, s);
        register_ioport_read(pm_io_base, 64, 2, pm_ioport_readw, s);
        register_ioport_write(pm_io_base, 64, 4, pm_ioport_writel, s);
        register_ioport_read(pm_io_base, 64, 4, pm_ioport_readl, s);
    }
}

static void pm_write_config(PCIDevice *d,
                            uint32_t address, uint32_t val, int len)
{
    pci_default_write_config(d, address, val, len);
    if (address == 0x80)
        pm_io_space_update((PIIX4PMState *)d);
}

static void pm_save(QEMUFile* f,void *opaque)
{
    PIIX4PMState *s = opaque;

    pci_device_save(&s->dev, f);

    qemu_put_be16s(f, &s->pmsts);
    qemu_put_be16s(f, &s->pmen);
    qemu_put_be16s(f, &s->pmcntrl);
    qemu_put_8s(f, &s->apmc);
    qemu_put_8s(f, &s->apms);
    qemu_put_timer(f, s->tmr_timer);
    qemu_put_be64(f, s->tmr_overflow_time);
}

static int pm_load(QEMUFile* f,void* opaque,int version_id)
{
    PIIX4PMState *s = opaque;
    int ret;

    if (version_id > 1)
        return -EINVAL;

    ret = pci_device_load(&s->dev, f);
    if (ret < 0)
        return ret;

    qemu_get_be16s(f, &s->pmsts);
    qemu_get_be16s(f, &s->pmen);
    qemu_get_be16s(f, &s->pmcntrl);
    qemu_get_8s(f, &s->apmc);
    qemu_get_8s(f, &s->apms);
    qemu_get_timer(f, s->tmr_timer);
    s->tmr_overflow_time=qemu_get_be64(f);

    pm_io_space_update(s);

    return 0;
}

i2c_bus *piix4_pm_init(PCIBus *bus, int devfn, uint32_t smb_io_base,
                       qemu_irq sci_irq)
{
    PIIX4PMState *s;
    uint8_t *pci_conf;

    s = (PIIX4PMState *)pci_register_device(bus,
                                         "PM", sizeof(PIIX4PMState),
                                         devfn, NULL, pm_write_config);
    pm_state = s;
    pci_conf = s->dev.config;
    pci_conf[0x00] = 0x86;
    pci_conf[0x01] = 0x80;
    pci_conf[0x02] = 0x13;
    pci_conf[0x03] = 0x71;
    pci_conf[0x06] = 0x80;
    pci_conf[0x07] = 0x02;
    pci_conf[0x08] = 0x03; // revision number
    pci_conf[0x09] = 0x00;
    pci_conf[0x0a] = 0x80; // other bridge device
    pci_conf[0x0b] = 0x06; // bridge device
    pci_conf[0x0e] = 0x00; // header_type
    pci_conf[0x3d] = 0x01; // interrupt pin 1

    pci_conf[0x40] = 0x01; /* PM io base read only bit */

    register_ioport_write(0xb2, 2, 1, pm_smi_writeb, s);
    register_ioport_read(0xb2, 2, 1, pm_smi_readb, s);

    register_ioport_write(ACPI_DBG_IO_ADDR, 4, 4, acpi_dbg_writel, s);

    /* XXX: which specification is used ? The i82731AB has different
       mappings */
    pci_conf[0x5f] = (parallel_hds[0] != NULL ? 0x80 : 0) | 0x10;
    pci_conf[0x63] = 0x60;
    pci_conf[0x67] = (serial_hds[0] != NULL ? 0x08 : 0) |
	(serial_hds[1] != NULL ? 0x90 : 0);

    pci_conf[0x90] = smb_io_base | 1;
    pci_conf[0x91] = smb_io_base >> 8;
    pci_conf[0xd2] = 0x09;
    register_ioport_write(smb_io_base, 64, 1, smb_ioport_writeb, s);
    register_ioport_read(smb_io_base, 64, 1, smb_ioport_readb, s);

    s->tmr_timer = qemu_new_timer(vm_clock, pm_tmr_timer, s);

    register_savevm("piix4_pm", 0, 1, pm_save, pm_load, s);

    s->smbus = i2c_init_bus();
    s->irq = sci_irq;
    return s->smbus;
}

#if defined(TARGET_I386)
void qemu_system_powerdown(void)
{
    if(pm_state->pmen & PWRBTN_EN) {
        pm_state->pmsts |= PWRBTN_EN;
	pm_update_sci(pm_state);
    }
}
#endif