/*
 * QEMU i440FX/PIIX3 PCI Bridge Emulation
 *
 * Copyright (c) 2006 Fabrice Bellard
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include "hw.h"
#include "pc.h"
#include "pci.h"
#include "isa.h"
#include "sysbus.h"

typedef uint32_t pci_addr_t;
#include "pci_host.h"

typedef PCIHostState I440FXState;

typedef struct PIIX3State {
    PCIDevice dev;
    int pci_irq_levels[4];
} PIIX3State;

typedef struct PIIX3IrqState {
    PIIX3State *piix3;
    qemu_irq *pic;
} PIIX3IrqState;

struct PCII440FXState {
    PCIDevice dev;
    target_phys_addr_t isa_page_descs[384 / 4];
    uint8_t smm_enabled;
    PIIX3IrqState *irq_state;
};

static void i440fx_addr_writel(void* opaque, uint32_t addr, uint32_t val)
{
    I440FXState *s = opaque;
    s->config_reg = val;
}

static uint32_t i440fx_addr_readl(void* opaque, uint32_t addr)
{
    I440FXState *s = opaque;
    return s->config_reg;
}

static void piix3_set_irq(void *opaque, int irq_num, int level);

/* return the global irq number corresponding to a given device irq
   pin. We could also use the bus number to have a more precise
   mapping. */
static int pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
{
    int slot_addend;
    slot_addend = (pci_dev->devfn >> 3) - 1;
    return (irq_num + slot_addend) & 3;
}

static void update_pam(PCII440FXState *d, uint32_t start, uint32_t end, int r)
{
    uint32_t addr;

    //    printf("ISA mapping %08x-0x%08x: %d\n", start, end, r);
    switch(r) {
    case 3:
        /* RAM */
        cpu_register_physical_memory(start, end - start,
                                     start);
        break;
    case 1:
        /* ROM (XXX: not quite correct) */
        cpu_register_physical_memory(start, end - start,
                                     start | IO_MEM_ROM);
        break;
    case 2:
    case 0:
        /* XXX: should distinguish read/write cases */
        for(addr = start; addr < end; addr += 4096) {
            cpu_register_physical_memory(addr, 4096,
                                         d->isa_page_descs[(addr - 0xa0000) >> 12]);
        }
        break;
    }
}

static void i440fx_update_memory_mappings(PCII440FXState *d)
{
    int i, r;
    uint32_t smram, addr;

    update_pam(d, 0xf0000, 0x100000, (d->dev.config[0x59] >> 4) & 3);
    for(i = 0; i < 12; i++) {
        r = (d->dev.config[(i >> 1) + 0x5a] >> ((i & 1) * 4)) & 3;
        update_pam(d, 0xc0000 + 0x4000 * i, 0xc0000 + 0x4000 * (i + 1), r);
    }
    smram = d->dev.config[0x72];
    if ((d->smm_enabled && (smram & 0x08)) || (smram & 0x40)) {
        cpu_register_physical_memory(0xa0000, 0x20000, 0xa0000);
    } else {
        for(addr = 0xa0000; addr < 0xc0000; addr += 4096) {
            cpu_register_physical_memory(addr, 4096,
                                         d->isa_page_descs[(addr - 0xa0000) >> 12]);
        }
    }
}

void i440fx_set_smm(PCII440FXState *d, int val)
{
    val = (val != 0);
    if (d->smm_enabled != val) {
        d->smm_enabled = val;
        i440fx_update_memory_mappings(d);
    }
}


/* XXX: suppress when better memory API. We make the assumption that
   no device (in particular the VGA) changes the memory mappings in
   the 0xa0000-0x100000 range */
void i440fx_init_memory_mappings(PCII440FXState *d)
{
    int i;
    for(i = 0; i < 96; i++) {
        d->isa_page_descs[i] = cpu_get_physical_page_desc(0xa0000 + i * 0x1000);
    }
}

static void i440fx_write_config(PCIDevice *dev,
                                uint32_t address, uint32_t val, int len)
{
    PCII440FXState *d = DO_UPCAST(PCII440FXState, dev, dev);

    /* XXX: implement SMRAM.D_LOCK */
    pci_default_write_config(dev, address, val, len);
    if ((address >= 0x59 && address <= 0x5f) || address == 0x72)
        i440fx_update_memory_mappings(d);
}

static void i440fx_save(QEMUFile* f, void *opaque)
{
    PCII440FXState *d = opaque;

    pci_device_save(&d->dev, f);
    qemu_put_8s(f, &d->smm_enabled);
}

static int i440fx_load(QEMUFile* f, void *opaque, int version_id)
{
    PCII440FXState *d = opaque;
    int ret, i;

    if (version_id > 3)
        return -EINVAL;
    ret = pci_device_load(&d->dev, f);
    if (ret < 0)
        return ret;
    i440fx_update_memory_mappings(d);
    qemu_get_8s(f, &d->smm_enabled);

    if (version_id == 2)
        for (i = 0; i < 4; i++)
            d->irq_state->piix3->pci_irq_levels[i] = qemu_get_be32(f);

    return 0;
}

static int i440fx_pcihost_initfn(SysBusDevice *dev)
{
    I440FXState *s = FROM_SYSBUS(I440FXState, dev);

    register_ioport_write(0xcf8, 4, 4, i440fx_addr_writel, s);
    register_ioport_read(0xcf8, 4, 4, i440fx_addr_readl, s);

    register_ioport_write(0xcfc, 4, 1, pci_host_data_writeb, s);
    register_ioport_write(0xcfc, 4, 2, pci_host_data_writew, s);
    register_ioport_write(0xcfc, 4, 4, pci_host_data_writel, s);
    register_ioport_read(0xcfc, 4, 1, pci_host_data_readb, s);
    register_ioport_read(0xcfc, 4, 2, pci_host_data_readw, s);
    register_ioport_read(0xcfc, 4, 4, pci_host_data_readl, s);
    return 0;
}

static int i440fx_initfn(PCIDevice *dev)
{
    PCII440FXState *d = DO_UPCAST(PCII440FXState, dev, dev);

    pci_config_set_vendor_id(d->dev.config, PCI_VENDOR_ID_INTEL);
    pci_config_set_device_id(d->dev.config, PCI_DEVICE_ID_INTEL_82441);
    d->dev.config[0x08] = 0x02; // revision
    pci_config_set_class(d->dev.config, PCI_CLASS_BRIDGE_HOST);
    d->dev.config[PCI_HEADER_TYPE] = PCI_HEADER_TYPE_NORMAL; // header_type

    d->dev.config[0x72] = 0x02; /* SMRAM */

    register_savevm("I440FX", 0, 3, i440fx_save, i440fx_load, d);
    return 0;
}

PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix3_devfn, qemu_irq *pic)
{
    DeviceState *dev;
    PCIBus *b;
    PCIDevice *d;
    I440FXState *s;
    PIIX3IrqState *irq_state = qemu_malloc(sizeof(*irq_state));

    irq_state->pic = pic;
    dev = qdev_create(NULL, "i440FX-pcihost");
    s = FROM_SYSBUS(I440FXState, sysbus_from_qdev(dev));
    b = pci_register_bus(&s->busdev.qdev, "pci.0",
                         piix3_set_irq, pci_slot_get_pirq, irq_state, 0, 4);
    s->bus = b;
    qdev_init(dev);

    d = pci_create_simple(b, 0, "i440FX");
    *pi440fx_state = DO_UPCAST(PCII440FXState, dev, d);
    (*pi440fx_state)->irq_state = irq_state;

    irq_state->piix3 = DO_UPCAST(PIIX3State, dev,
                                 pci_create_simple(b, -1, "PIIX3"));
    *piix3_devfn = irq_state->piix3->dev.devfn;

    return b;
}

/* PIIX3 PCI to ISA bridge */

static void piix3_set_irq(void *opaque, int irq_num, int level)
{
    int i, pic_irq, pic_level;
    PIIX3IrqState *irq_state = opaque;

    irq_state->piix3->pci_irq_levels[irq_num] = level;

    /* now we change the pic irq level according to the piix irq mappings */
    /* XXX: optimize */
    pic_irq = irq_state->piix3->dev.config[0x60 + irq_num];
    if (pic_irq < 16) {
        /* The pic level is the logical OR of all the PCI irqs mapped
           to it */
        pic_level = 0;
        for (i = 0; i < 4; i++) {
            if (pic_irq == irq_state->piix3->dev.config[0x60 + i])
                pic_level |= irq_state->piix3->pci_irq_levels[i];
        }
        qemu_set_irq(irq_state->pic[pic_irq], pic_level);
    }
}

static void piix3_reset(void *opaque)
{
    PIIX3State *d = opaque;
    uint8_t *pci_conf = d->dev.config;

    pci_conf[0x04] = 0x07; // master, memory and I/O
    pci_conf[0x05] = 0x00;
    pci_conf[0x06] = 0x00;
    pci_conf[0x07] = 0x02; // PCI_status_devsel_medium
    pci_conf[0x4c] = 0x4d;
    pci_conf[0x4e] = 0x03;
    pci_conf[0x4f] = 0x00;
    pci_conf[0x60] = 0x80;
    pci_conf[0x61] = 0x80;
    pci_conf[0x62] = 0x80;
    pci_conf[0x63] = 0x80;
    pci_conf[0x69] = 0x02;
    pci_conf[0x70] = 0x80;
    pci_conf[0x76] = 0x0c;
    pci_conf[0x77] = 0x0c;
    pci_conf[0x78] = 0x02;
    pci_conf[0x79] = 0x00;
    pci_conf[0x80] = 0x00;
    pci_conf[0x82] = 0x00;
    pci_conf[0xa0] = 0x08;
    pci_conf[0xa2] = 0x00;
    pci_conf[0xa3] = 0x00;
    pci_conf[0xa4] = 0x00;
    pci_conf[0xa5] = 0x00;
    pci_conf[0xa6] = 0x00;
    pci_conf[0xa7] = 0x00;
    pci_conf[0xa8] = 0x0f;
    pci_conf[0xaa] = 0x00;
    pci_conf[0xab] = 0x00;
    pci_conf[0xac] = 0x00;
    pci_conf[0xae] = 0x00;

    memset(d->pci_irq_levels, 0, sizeof(d->pci_irq_levels));
}

static void piix3_save(QEMUFile* f, void *opaque)
{
    PIIX3State *d = opaque;
    int i;

    pci_device_save(&d->dev, f);

    for (i = 0; i < 4; i++)
        qemu_put_be32(f, d->pci_irq_levels[i]);
}

static int piix3_load(QEMUFile* f, void *opaque, int version_id)
{
    PIIX3State *d = opaque;
    int i, ret;

    if (version_id > 3 || version_id < 2)
        return -EINVAL;
    ret = pci_device_load(&d->dev, f);
    if (ret < 0)
        return ret;
    if (version_id >= 3) {
        for (i = 0; i < 4; i++)
            d->pci_irq_levels[i] = qemu_get_be32(f);
    }
    return 0;
}

static int piix3_initfn(PCIDevice *dev)
{
    PIIX3State *d = DO_UPCAST(PIIX3State, dev, dev);
    uint8_t *pci_conf;

    isa_bus_new(&d->dev.qdev);
    register_savevm("PIIX3", 0, 3, piix3_save, piix3_load, d);

    pci_conf = d->dev.config;
    pci_config_set_vendor_id(pci_conf, PCI_VENDOR_ID_INTEL);
    pci_config_set_device_id(pci_conf, PCI_DEVICE_ID_INTEL_82371SB_0); // 82371SB PIIX3 PCI-to-ISA bridge (Step A1)
    pci_config_set_class(pci_conf, PCI_CLASS_BRIDGE_ISA);
    pci_conf[PCI_HEADER_TYPE] =
        PCI_HEADER_TYPE_NORMAL | PCI_HEADER_TYPE_MULTI_FUNCTION; // header_type = PCI_multifunction, generic

    piix3_reset(d);
    qemu_register_reset(piix3_reset, d);
    return 0;
}

static PCIDeviceInfo i440fx_info[] = {
    {
        .qdev.name    = "i440FX",
        .qdev.desc    = "Host bridge",
        .qdev.size    = sizeof(PCII440FXState),
        .qdev.no_user = 1,
        .init         = i440fx_initfn,
        .config_write = i440fx_write_config,
    },{
        .qdev.name    = "PIIX3",
        .qdev.desc    = "ISA bridge",
        .qdev.size    = sizeof(PIIX3State),
        .qdev.no_user = 1,
        .init         = piix3_initfn,
    },{
        /* end of list */
    }
};

static SysBusDeviceInfo i440fx_pcihost_info = {
    .init         = i440fx_pcihost_initfn,
    .qdev.name    = "i440FX-pcihost",
    .qdev.size    = sizeof(I440FXState),
    .qdev.no_user = 1,
};

static void i440fx_register(void)
{
    sysbus_register_withprop(&i440fx_pcihost_info);
    pci_qdev_register_many(i440fx_info);
}
device_init(i440fx_register);