/*
 *  Copyright (C) 1998-2000  Andre Hedrick <andre@linux-ide.org>
 *  Copyright (C) 1995-1998  Mark Lord
 *  Copyright (C) 2007-2009  Bartlomiej Zolnierkiewicz
 *
 *  May be copied or modified under the terms of the GNU General Public License
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/ide.h>
#include <linux/dma-mapping.h>

#include <asm/io.h>

/**
 *      ide_setup_pci_baseregs  -       place a PCI IDE controller native
 *      @dev: PCI device of interface to switch native
 *      @name: Name of interface
 *
 *      We attempt to place the PCI interface into PCI native mode. If
 *      we succeed the BARs are ok and the controller is in PCI mode.
 *      Returns 0 on success or an errno code.
 *
 *      FIXME: if we program the interface and then fail to set the BARS
 *      we don't switch it back to legacy mode. Do we actually care ??
 */

static int ide_setup_pci_baseregs(struct pci_dev *dev, const char *name)
{
        u8 progif = 0;

        /*
         * Place both IDE interfaces into PCI "native" mode:
         */
        if (pci_read_config_byte(dev, PCI_CLASS_PROG, &progif) ||
                         (progif & 5) != 5) {
                if ((progif & 0xa) != 0xa) {
                        printk(KERN_INFO "%s %s: device not capable of full "
                                "native PCI mode\n", name, pci_name(dev));
                        return -EOPNOTSUPP;
                }
                printk(KERN_INFO "%s %s: placing both ports into native PCI "
                        "mode\n", name, pci_name(dev));
                (void) pci_write_config_byte(dev, PCI_CLASS_PROG, progif|5);
                if (pci_read_config_byte(dev, PCI_CLASS_PROG, &progif) ||
                    (progif & 5) != 5) {
                        printk(KERN_ERR "%s %s: rewrite of PROGIF failed, "
                                "wanted 0x%04x, got 0x%04x\n",
                                name, pci_name(dev), progif | 5, progif);
                        return -EOPNOTSUPP;
                }
        }
        return 0;
}

#ifdef CONFIG_BLK_DEV_IDEDMA_PCI
static int ide_pci_clear_simplex(unsigned long dma_base, const char *name)
{
        u8 dma_stat = inb(dma_base + 2);

        outb(dma_stat & 0x60, dma_base + 2);
        dma_stat = inb(dma_base + 2);

        return (dma_stat & 0x80) ? 1 : 0;
}

/**
 *      ide_pci_dma_base        -       setup BMIBA
 *      @hwif: IDE interface
 *      @d: IDE port info
 *
 *      Fetch the DMA Bus-Master-I/O-Base-Address (BMIBA) from PCI space.
 */

unsigned long ide_pci_dma_base(ide_hwif_t *hwif, const struct ide_port_info *d)
{
        struct pci_dev *dev = to_pci_dev(hwif->dev);
        unsigned long dma_base = 0;

        if (hwif->host_flags & IDE_HFLAG_MMIO)
                return hwif->dma_base;

        if (hwif->mate && hwif->mate->dma_base) {
                dma_base = hwif->mate->dma_base - (hwif->channel ? 0 : 8);
        } else {
                u8 baridx = (d->host_flags & IDE_HFLAG_CS5520) ? 2 : 4;

                dma_base = pci_resource_start(dev, baridx);

                if (dma_base == 0) {
                        printk(KERN_ERR "%s %s: DMA base is invalid\n",
                                d->name, pci_name(dev));
                        return 0;
                }
        }

        if (hwif->channel)
                dma_base += 8;

        return dma_base;
}
EXPORT_SYMBOL_GPL(ide_pci_dma_base);

int ide_pci_check_simplex(ide_hwif_t *hwif, const struct ide_port_info *d)
{
        struct pci_dev *dev = to_pci_dev(hwif->dev);
        u8 dma_stat;

        if (d->host_flags & (IDE_HFLAG_MMIO | IDE_HFLAG_CS5520))
                goto out;

        if (d->host_flags & IDE_HFLAG_CLEAR_SIMPLEX) {
                if (ide_pci_clear_simplex(hwif->dma_base, d->name))
                        printk(KERN_INFO "%s %s: simplex device: DMA forced\n",
                                d->name, pci_name(dev));
                goto out;
        }

        /*
         * If the device claims "simplex" DMA, this means that only one of
         * the two interfaces can be trusted with DMA at any point in time
         * (so we should enable DMA only on one of the two interfaces).
         *
         * FIXME: At this point we haven't probed the drives so we can't make
         * the appropriate decision.  Really we should defer this problem until
         * we tune the drive then try to grab DMA ownership if we want to be
         * the DMA end.  This has to be become dynamic to handle hot-plug.
         */
        dma_stat = hwif->dma_ops->dma_sff_read_status(hwif);
        if ((dma_stat & 0x80) && hwif->mate && hwif->mate->dma_base) {
                printk(KERN_INFO "%s %s: simplex device: DMA disabled\n",
                        d->name, pci_name(dev));
                return -1;
        }
out:
        return 0;
}
EXPORT_SYMBOL_GPL(ide_pci_check_simplex);

/*
 * Set up BM-DMA capability (PnP BIOS should have done this)
 */
int ide_pci_set_master(struct pci_dev *dev, const char *name)
{
        u16 pcicmd;

        pci_read_config_word(dev, PCI_COMMAND, &pcicmd);

        if ((pcicmd & PCI_COMMAND_MASTER) == 0) {
                pci_set_master(dev);

                if (pci_read_config_word(dev, PCI_COMMAND, &pcicmd) ||
                    (pcicmd & PCI_COMMAND_MASTER) == 0) {
                        printk(KERN_ERR "%s %s: error updating PCICMD\n",
                                name, pci_name(dev));
                        return -EIO;
                }
        }

        return 0;
}
EXPORT_SYMBOL_GPL(ide_pci_set_master);
#endif /* CONFIG_BLK_DEV_IDEDMA_PCI */

void ide_setup_pci_noise(struct pci_dev *dev, const struct ide_port_info *d)
{
        printk(KERN_INFO "%s %s: IDE controller (0x%04x:0x%04x rev 0x%02x)\n",
                d->name, pci_name(dev),
                dev->vendor, dev->device, dev->revision);
}
EXPORT_SYMBOL_GPL(ide_setup_pci_noise);


/**
 *      ide_pci_enable  -       do PCI enables
 *      @dev: PCI device
 *      @d: IDE port info
 *
 *      Enable the IDE PCI device. We attempt to enable the device in full
 *      but if that fails then we only need IO space. The PCI code should
 *      have setup the proper resources for us already for controllers in
 *      legacy mode.
 *
 *      Returns zero on success or an error code
 */

static int ide_pci_enable(struct pci_dev *dev, const struct ide_port_info *d)
{
        int ret, bars;

        if (pci_enable_device(dev)) {
                ret = pci_enable_device_io(dev);
                if (ret < 0) {
                        printk(KERN_WARNING "%s %s: couldn't enable device\n",
                                d->name, pci_name(dev));
                        goto out;
                }
                printk(KERN_WARNING "%s %s: BIOS configuration fixed\n",
                        d->name, pci_name(dev));
        }

        /*
         * assume all devices can do 32-bit DMA for now, we can add
         * a DMA mask field to the struct ide_port_info if we need it
         * (or let lower level driver set the DMA mask)
         */
        ret = pci_set_dma_mask(dev, DMA_BIT_MASK(32));
        if (ret < 0) {
                printk(KERN_ERR "%s %s: can't set DMA mask\n",
                        d->name, pci_name(dev));
                goto out;
        }

        if (d->host_flags & IDE_HFLAG_SINGLE)
                bars = (1 << 2) - 1;
        else
                bars = (1 << 4) - 1;

        if ((d->host_flags & IDE_HFLAG_NO_DMA) == 0) {
                if (d->host_flags & IDE_HFLAG_CS5520)
                        bars |= (1 << 2);
                else
                        bars |= (1 << 4);
        }

        ret = pci_request_selected_regions(dev, bars, d->name);
        if (ret < 0)
                printk(KERN_ERR "%s %s: can't reserve resources\n",
                        d->name, pci_name(dev));
out:
        return ret;
}

/**
 *      ide_pci_configure       -       configure an unconfigured device
 *      @dev: PCI device
 *      @d: IDE port info
 *
 *      Enable and configure the PCI device we have been passed.
 *      Returns zero on success or an error code.
 */

static int ide_pci_configure(struct pci_dev *dev, const struct ide_port_info *d)
{
        u16 pcicmd = 0;
        /*
         * PnP BIOS was *supposed* to have setup this device, but we
         * can do it ourselves, so long as the BIOS has assigned an IRQ
         * (or possibly the device is using a "legacy header" for IRQs).
         * Maybe the user deliberately *disabled* the device,
         * but we'll eventually ignore it again if no drives respond.
         */
        if (ide_setup_pci_baseregs(dev, d->name) ||
            pci_write_config_word(dev, PCI_COMMAND, pcicmd | PCI_COMMAND_IO)) {
                printk(KERN_INFO "%s %s: device disabled (BIOS)\n",
                        d->name, pci_name(dev));
                return -ENODEV;
        }
        if (pci_read_config_word(dev, PCI_COMMAND, &pcicmd)) {
                printk(KERN_ERR "%s %s: error accessing PCI regs\n",
                        d->name, pci_name(dev));
                return -EIO;
        }
        if (!(pcicmd & PCI_COMMAND_IO)) {
                printk(KERN_ERR "%s %s: unable to enable IDE controller\n",
                        d->name, pci_name(dev));
                return -ENXIO;
        }
        return 0;
}

/**
 *      ide_pci_check_iomem     -       check a register is I/O
 *      @dev: PCI device
 *      @d: IDE port info
 *      @bar: BAR number
 *
 *      Checks if a BAR is configured and points to MMIO space. If so,
 *      return an error code. Otherwise return 0
 */

static int ide_pci_check_iomem(struct pci_dev *dev, const struct ide_port_info *d,
                               int bar)
{
        ulong flags = pci_resource_flags(dev, bar);

        /* Unconfigured ? */
        if (!flags || pci_resource_len(dev, bar) == 0)
                return 0;

        /* I/O space */
        if (flags & IORESOURCE_IO)
                return 0;

        /* Bad */
        return -EINVAL;
}

/**
 *      ide_hw_configure        -       configure a struct ide_hw instance
 *      @dev: PCI device holding interface
 *      @d: IDE port info
 *      @port: port number
 *      @hw: struct ide_hw instance corresponding to this port
 *
 *      Perform the initial set up for the hardware interface structure. This
 *      is done per interface port rather than per PCI device. There may be
 *      more than one port per device.
 *
 *      Returns zero on success or an error code.
 */

static int ide_hw_configure(struct pci_dev *dev, const struct ide_port_info *d,
                            unsigned int port, struct ide_hw *hw)
{
        unsigned long ctl = 0, base = 0;

        if ((d->host_flags & IDE_HFLAG_ISA_PORTS) == 0) {
                if (ide_pci_check_iomem(dev, d, 2 * port) ||
                    ide_pci_check_iomem(dev, d, 2 * port + 1)) {
                        printk(KERN_ERR "%s %s: I/O baseregs (BIOS) are "
                                "reported as MEM for port %d!\n",
                                d->name, pci_name(dev), port);
                        return -EINVAL;
                }

                ctl  = pci_resource_start(dev, 2*port+1);
                base = pci_resource_start(dev, 2*port);
        } else {
                /* Use default values */
                ctl = port ? 0x374 : 0x3f4;
                base = port ? 0x170 : 0x1f0;
        }

        if (!base || !ctl) {
                printk(KERN_ERR "%s %s: bad PCI BARs for port %d, skipping\n",
                        d->name, pci_name(dev), port);
                return -EINVAL;
        }

        memset(hw, 0, sizeof(*hw));
        hw->dev = &dev->dev;
        ide_std_init_ports(hw, base, ctl | 2);

        return 0;
}

#ifdef CONFIG_BLK_DEV_IDEDMA_PCI
/**
 *      ide_hwif_setup_dma      -       configure DMA interface
 *      @hwif: IDE interface
 *      @d: IDE port info
 *
 *      Set up the DMA base for the interface. Enable the master bits as
 *      necessary and attempt to bring the device DMA into a ready to use
 *      state
 */

int ide_hwif_setup_dma(ide_hwif_t *hwif, const struct ide_port_info *d)
{
        struct pci_dev *dev = to_pci_dev(hwif->dev);

        if ((d->host_flags & IDE_HFLAG_NO_AUTODMA) == 0 ||
            ((dev->class >> 8) == PCI_CLASS_STORAGE_IDE &&
             (dev->class & 0x80))) {
                unsigned long base = ide_pci_dma_base(hwif, d);

                if (base == 0)
                        return -1;

                hwif->dma_base = base;

                if (hwif->dma_ops == NULL)
                        hwif->dma_ops = &sff_dma_ops;

                if (ide_pci_check_simplex(hwif, d) < 0)
                        return -1;

                if (ide_pci_set_master(dev, d->name) < 0)
                        return -1;

                if (hwif->host_flags & IDE_HFLAG_MMIO)
                        printk(KERN_INFO "    %s: MMIO-DMA\n", hwif->name);
                else
                        printk(KERN_INFO "    %s: BM-DMA at 0x%04lx-0x%04lx\n",
                                         hwif->name, base, base + 7);

                hwif->extra_base = base + (hwif->channel ? 8 : 16);

                if (ide_allocate_dma_engine(hwif))
                        return -1;
        }

        return 0;
}
#endif /* CONFIG_BLK_DEV_IDEDMA_PCI */

/**
 *      ide_setup_pci_controller        -       set up IDE PCI
 *      @dev: PCI device
 *      @d: IDE port info
 *      @noisy: verbose flag
 *
 *      Set up the PCI and controller side of the IDE interface. This brings
 *      up the PCI side of the device, checks that the device is enabled
 *      and enables it if need be
 */

static int ide_setup_pci_controller(struct pci_dev *dev,
                                    const struct ide_port_info *d, int noisy)
{
        int ret;
        u16 pcicmd;

        if (noisy)
                ide_setup_pci_noise(dev, d);

        ret = ide_pci_enable(dev, d);
        if (ret < 0)
                goto out;

        ret = pci_read_config_word(dev, PCI_COMMAND, &pcicmd);
        if (ret < 0) {
                printk(KERN_ERR "%s %s: error accessing PCI regs\n",
                        d->name, pci_name(dev));
                goto out;
        }
        if (!(pcicmd & PCI_COMMAND_IO)) {       /* is device disabled? */
                ret = ide_pci_configure(dev, d);
                if (ret < 0)
                        goto out;
                printk(KERN_INFO "%s %s: device enabled (Linux)\n",
                        d->name, pci_name(dev));
        }

out:
        return ret;
}

/**
 *      ide_pci_setup_ports     -       configure ports/devices on PCI IDE
 *      @dev: PCI device
 *      @d: IDE port info
 *      @hw: struct ide_hw instances corresponding to this PCI IDE device
 *      @hws: struct ide_hw pointers table to update
 *
 *      Scan the interfaces attached to this device and do any
 *      necessary per port setup. Attach the devices and ask the
 *      generic DMA layer to do its work for us.
 *
 *      Normally called automaticall from do_ide_pci_setup_device,
 *      but is also used directly as a helper function by some controllers
 *      where the chipset setup is not the default PCI IDE one.
 */

void ide_pci_setup_ports(struct pci_dev *dev, const struct ide_port_info *d,
                         struct ide_hw *hw, struct ide_hw **hws)
{
        int channels = (d->host_flags & IDE_HFLAG_SINGLE) ? 1 : 2, port;
        u8 tmp;

        /*
         * Set up the IDE ports
         */

        for (port = 0; port < channels; ++port) {
                const struct ide_pci_enablebit *e = &d->enablebits[port];

                if (e->reg && (pci_read_config_byte(dev, e->reg, &tmp) ||
                    (tmp & e->mask) != e->val)) {
                        printk(KERN_INFO "%s %s: IDE port disabled\n",
                                d->name, pci_name(dev));
                        continue;       /* port not enabled */
                }

                if (ide_hw_configure(dev, d, port, hw + port))
                        continue;

                *(hws + port) = hw + port;
        }
}
EXPORT_SYMBOL_GPL(ide_pci_setup_ports);

/*
 * ide_setup_pci_device() looks at the primary/secondary interfaces
 * on a PCI IDE device and, if they are enabled, prepares the IDE driver
 * for use with them.  This generic code works for most PCI chipsets.
 *
 * One thing that is not standardized is the location of the
 * primary/secondary interface "enable/disable" bits.  For chipsets that
 * we "know" about, this information is in the struct ide_port_info;
 * for all other chipsets, we just assume both interfaces are enabled.
 */
static int do_ide_setup_pci_device(struct pci_dev *dev,
                                   const struct ide_port_info *d,
                                   u8 noisy)
{
        int pciirq, ret;

        /*
         * Can we trust the reported IRQ?
         */
        pciirq = dev->irq;

        /*
         * This allows offboard ide-pci cards the enable a BIOS,
         * verify interrupt settings of split-mirror pci-config
         * space, place chipset into init-mode, and/or preserve
         * an interrupt if the card is not native ide support.
         */
        ret = d->init_chipset ? d->init_chipset(dev) : 0;
        if (ret < 0)
                goto out;

        if (ide_pci_is_in_compatibility_mode(dev)) {
                if (noisy)
                        printk(KERN_INFO "%s %s: not 100%% native mode: will "
                                "probe irqs later\n", d->name, pci_name(dev));
                pciirq = 0;
        } else if (!pciirq && noisy) {
                printk(KERN_WARNING "%s %s: bad irq (%d): will probe later\n",
                        d->name, pci_name(dev), pciirq);
        } else if (noisy) {
                printk(KERN_INFO "%s %s: 100%% native mode on irq %d\n",
                        d->name, pci_name(dev), pciirq);
        }

        ret = pciirq;
out:
        return ret;
}

int ide_pci_init_two(struct pci_dev *dev1, struct pci_dev *dev2,
                     const struct ide_port_info *d, void *priv)
{
        struct pci_dev *pdev[] = { dev1, dev2 };
        struct ide_host *host;
        int ret, i, n_ports = dev2 ? 4 : 2;
        struct ide_hw hw[4], *hws[] = { NULL, NULL, NULL, NULL };

        for (i = 0; i < n_ports / 2; i++) {
                ret = ide_setup_pci_controller(pdev[i], d, !i);
                if (ret < 0)
                        goto out;

                ide_pci_setup_ports(pdev[i], d, &hw[i*2], &hws[i*2]);
        }

        host = ide_host_alloc(d, hws, n_ports);
        if (host == NULL) {
                ret = -ENOMEM;
                goto out;
        }

        host->dev[0] = &dev1->dev;
        if (dev2)
                host->dev[1] = &dev2->dev;

        host->host_priv = priv;
        host->irq_flags = IRQF_SHARED;

        pci_set_drvdata(pdev[0], host);
        if (dev2)
                pci_set_drvdata(pdev[1], host);

        for (i = 0; i < n_ports / 2; i++) {
                ret = do_ide_setup_pci_device(pdev[i], d, !i);

                /*
                 * FIXME: Mom, mom, they stole me the helper function to undo
                 * do_ide_setup_pci_device() on the first device!
                 */
                if (ret < 0)
                        goto out;

                /* fixup IRQ */
                if (ide_pci_is_in_compatibility_mode(pdev[i])) {
                        hw[i*2].irq = pci_get_legacy_ide_irq(pdev[i], 0);
                        hw[i*2 + 1].irq = pci_get_legacy_ide_irq(pdev[i], 1);
                } else
                        hw[i*2 + 1].irq = hw[i*2].irq = ret;
        }

        ret = ide_host_register(host, d, hws);
        if (ret)
                ide_host_free(host);
out:
        return ret;
}
EXPORT_SYMBOL_GPL(ide_pci_init_two);

int ide_pci_init_one(struct pci_dev *dev, const struct ide_port_info *d,
                     void *priv)
{
        return ide_pci_init_two(dev, NULL, d, priv);
}
EXPORT_SYMBOL_GPL(ide_pci_init_one);

void ide_pci_remove(struct pci_dev *dev)
{
        struct ide_host *host = pci_get_drvdata(dev);
        struct pci_dev *dev2 = host->dev[1] ? to_pci_dev(host->dev[1]) : NULL;
        int bars;

        if (host->host_flags & IDE_HFLAG_SINGLE)
                bars = (1 << 2) - 1;
        else
                bars = (1 << 4) - 1;

        if ((host->host_flags & IDE_HFLAG_NO_DMA) == 0) {
                if (host->host_flags & IDE_HFLAG_CS5520)
                        bars |= (1 << 2);
                else
                        bars |= (1 << 4);
        }

        ide_host_remove(host);

        if (dev2)
                pci_release_selected_regions(dev2, bars);
        pci_release_selected_regions(dev, bars);

        if (dev2)
                pci_disable_device(dev2);
        pci_disable_device(dev);
}
EXPORT_SYMBOL_GPL(ide_pci_remove);

#ifdef CONFIG_PM
int ide_pci_suspend(struct pci_dev *dev, pm_message_t state)
{
        pci_save_state(dev);
        pci_disable_device(dev);
        pci_set_power_state(dev, pci_choose_state(dev, state));

        return 0;
}
EXPORT_SYMBOL_GPL(ide_pci_suspend);

int ide_pci_resume(struct pci_dev *dev)
{
        struct ide_host *host = pci_get_drvdata(dev);
        int rc;

        pci_set_power_state(dev, PCI_D0);

        rc = pci_enable_device(dev);
        if (rc)
                return rc;

        pci_restore_state(dev);
        pci_set_master(dev);

        if (host->init_chipset)
                host->init_chipset(dev);

        return 0;
}
EXPORT_SYMBOL_GPL(ide_pci_resume);
#endif