/*
 *  sata_sil.c - Silicon Image SATA
 *
 *  Maintained by:  Tejun Heo <tj@kernel.org>
 *                  Please ALWAYS copy linux-ide@vger.kernel.org
 *                  on emails.
 *
 *  Copyright 2003-2005 Red Hat, Inc.
 *  Copyright 2003 Benjamin Herrenschmidt
 *
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2, or (at your option)
 *  any later version.
 *
 *  This program 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; see the file COPYING.  If not, write to
 *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *
 *  libata documentation is available via 'make {ps|pdf}docs',
 *  as Documentation/driver-api/libata.rst
 *
 *  Documentation for SiI 3112:
 *  http://gkernel.sourceforge.net/specs/sii/3112A_SiI-DS-0095-B2.pdf.bz2
 *
 *  Other errata and documentation available under NDA.
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/device.h>
#include <scsi/scsi_host.h>
#include <linux/libata.h>
#include <linux/dmi.h>

#define DRV_NAME        "sata_sil"
#define DRV_VERSION     "2.4"

#define SIL_DMA_BOUNDARY        0x7fffffffUL

enum {
        SIL_MMIO_BAR            = 5,

        /*
         * host flags
         */
        SIL_FLAG_NO_SATA_IRQ    = (1 << 28),
        SIL_FLAG_RERR_ON_DMA_ACT = (1 << 29),
        SIL_FLAG_MOD15WRITE     = (1 << 30),

        SIL_DFL_PORT_FLAGS      = ATA_FLAG_SATA,

        /*
         * Controller IDs
         */
        sil_3112                = 0,
        sil_3112_no_sata_irq    = 1,
        sil_3512                = 2,
        sil_3114                = 3,

        /*
         * Register offsets
         */
        SIL_SYSCFG              = 0x48,

        /*
         * Register bits
         */
        /* SYSCFG */
        SIL_MASK_IDE0_INT       = (1 << 22),
        SIL_MASK_IDE1_INT       = (1 << 23),
        SIL_MASK_IDE2_INT       = (1 << 24),
        SIL_MASK_IDE3_INT       = (1 << 25),
        SIL_MASK_2PORT          = SIL_MASK_IDE0_INT | SIL_MASK_IDE1_INT,
        SIL_MASK_4PORT          = SIL_MASK_2PORT |
                                  SIL_MASK_IDE2_INT | SIL_MASK_IDE3_INT,

        /* BMDMA/BMDMA2 */
        SIL_INTR_STEERING       = (1 << 1),

        SIL_DMA_ENABLE          = (1 << 0),  /* DMA run switch */
        SIL_DMA_RDWR            = (1 << 3),  /* DMA Rd-Wr */
        SIL_DMA_SATA_IRQ        = (1 << 4),  /* OR of all SATA IRQs */
        SIL_DMA_ACTIVE          = (1 << 16), /* DMA running */
        SIL_DMA_ERROR           = (1 << 17), /* PCI bus error */
        SIL_DMA_COMPLETE        = (1 << 18), /* cmd complete / IRQ pending */
        SIL_DMA_N_SATA_IRQ      = (1 << 6),  /* SATA_IRQ for the next channel */
        SIL_DMA_N_ACTIVE        = (1 << 24), /* ACTIVE for the next channel */
        SIL_DMA_N_ERROR         = (1 << 25), /* ERROR for the next channel */
        SIL_DMA_N_COMPLETE      = (1 << 26), /* COMPLETE for the next channel */

        /* SIEN */
        SIL_SIEN_N              = (1 << 16), /* triggered by SError.N */

        /*
         * Others
         */
        SIL_QUIRK_MOD15WRITE    = (1 << 0),
        SIL_QUIRK_UDMA5MAX      = (1 << 1),
};

static int sil_init_one(struct pci_dev *pdev, const struct pci_device_id *ent);
#ifdef CONFIG_PM_SLEEP
static int sil_pci_device_resume(struct pci_dev *pdev);
#endif
static void sil_dev_config(struct ata_device *dev);
static int sil_scr_read(struct ata_link *link, unsigned int sc_reg, u32 *val);
static int sil_scr_write(struct ata_link *link, unsigned int sc_reg, u32 val);
static int sil_set_mode(struct ata_link *link, struct ata_device **r_failed);
static void sil_qc_prep(struct ata_queued_cmd *qc);
static void sil_bmdma_setup(struct ata_queued_cmd *qc);
static void sil_bmdma_start(struct ata_queued_cmd *qc);
static void sil_bmdma_stop(struct ata_queued_cmd *qc);
static void sil_freeze(struct ata_port *ap);
static void sil_thaw(struct ata_port *ap);


static const struct pci_device_id sil_pci_tbl[] = {
        { PCI_VDEVICE(CMD, 0x3112), sil_3112 },
        { PCI_VDEVICE(CMD, 0x0240), sil_3112 },
        { PCI_VDEVICE(CMD, 0x3512), sil_3512 },
        { PCI_VDEVICE(CMD, 0x3114), sil_3114 },
        { PCI_VDEVICE(ATI, 0x436e), sil_3112 },
        { PCI_VDEVICE(ATI, 0x4379), sil_3112_no_sata_irq },
        { PCI_VDEVICE(ATI, 0x437a), sil_3112_no_sata_irq },

        { }     /* terminate list */
};


/* TODO firmware versions should be added - eric */
static const struct sil_drivelist {
        const char *product;
        unsigned int quirk;
} sil_blacklist [] = {
        { "ST320012AS",         SIL_QUIRK_MOD15WRITE },
        { "ST330013AS",         SIL_QUIRK_MOD15WRITE },
        { "ST340017AS",         SIL_QUIRK_MOD15WRITE },
        { "ST360015AS",         SIL_QUIRK_MOD15WRITE },
        { "ST380023AS",         SIL_QUIRK_MOD15WRITE },
        { "ST3120023AS",        SIL_QUIRK_MOD15WRITE },
        { "ST340014ASL",        SIL_QUIRK_MOD15WRITE },
        { "ST360014ASL",        SIL_QUIRK_MOD15WRITE },
        { "ST380011ASL",        SIL_QUIRK_MOD15WRITE },
        { "ST3120022ASL",       SIL_QUIRK_MOD15WRITE },
        { "ST3160021ASL",       SIL_QUIRK_MOD15WRITE },
        { "TOSHIBA MK2561GSYN", SIL_QUIRK_MOD15WRITE },
        { "Maxtor 4D060H3",     SIL_QUIRK_UDMA5MAX },
        { }
};

static struct pci_driver sil_pci_driver = {
        .name                   = DRV_NAME,
        .id_table               = sil_pci_tbl,
        .probe                  = sil_init_one,
        .remove                 = ata_pci_remove_one,
#ifdef CONFIG_PM_SLEEP
        .suspend                = ata_pci_device_suspend,
        .resume                 = sil_pci_device_resume,
#endif
};

static struct scsi_host_template sil_sht = {
        ATA_BASE_SHT(DRV_NAME),
        /** These controllers support Large Block Transfer which allows
            transfer chunks up to 2GB and which cross 64KB boundaries,
            therefore the DMA limits are more relaxed than standard ATA SFF. */
        .dma_boundary           = SIL_DMA_BOUNDARY,
        .sg_tablesize           = ATA_MAX_PRD
};

static struct ata_port_operations sil_ops = {
        .inherits               = &ata_bmdma32_port_ops,
        .dev_config             = sil_dev_config,
        .set_mode               = sil_set_mode,
        .bmdma_setup            = sil_bmdma_setup,
        .bmdma_start            = sil_bmdma_start,
        .bmdma_stop             = sil_bmdma_stop,
        .qc_prep                = sil_qc_prep,
        .freeze                 = sil_freeze,
        .thaw                   = sil_thaw,
        .scr_read               = sil_scr_read,
        .scr_write              = sil_scr_write,
};

static const struct ata_port_info sil_port_info[] = {
        /* sil_3112 */
        {
                .flags          = SIL_DFL_PORT_FLAGS | SIL_FLAG_MOD15WRITE,
                .pio_mask       = ATA_PIO4,
                .mwdma_mask     = ATA_MWDMA2,
                .udma_mask      = ATA_UDMA5,
                .port_ops       = &sil_ops,
        },
        /* sil_3112_no_sata_irq */
        {
                .flags          = SIL_DFL_PORT_FLAGS | SIL_FLAG_MOD15WRITE |
                                  SIL_FLAG_NO_SATA_IRQ,
                .pio_mask       = ATA_PIO4,
                .mwdma_mask     = ATA_MWDMA2,
                .udma_mask      = ATA_UDMA5,
                .port_ops       = &sil_ops,
        },
        /* sil_3512 */
        {
                .flags          = SIL_DFL_PORT_FLAGS | SIL_FLAG_RERR_ON_DMA_ACT,
                .pio_mask       = ATA_PIO4,
                .mwdma_mask     = ATA_MWDMA2,
                .udma_mask      = ATA_UDMA5,
                .port_ops       = &sil_ops,
        },
        /* sil_3114 */
        {
                .flags          = SIL_DFL_PORT_FLAGS | SIL_FLAG_RERR_ON_DMA_ACT,
                .pio_mask       = ATA_PIO4,
                .mwdma_mask     = ATA_MWDMA2,
                .udma_mask      = ATA_UDMA5,
                .port_ops       = &sil_ops,
        },
};

/* per-port register offsets */
/* TODO: we can probably calculate rather than use a table */
static const struct {
        unsigned long tf;       /* ATA taskfile register block */
        unsigned long ctl;      /* ATA control/altstatus register block */
        unsigned long bmdma;    /* DMA register block */
        unsigned long bmdma2;   /* DMA register block #2 */
        unsigned long fifo_cfg; /* FIFO Valid Byte Count and Control */
        unsigned long scr;      /* SATA control register block */
        unsigned long sien;     /* SATA Interrupt Enable register */
        unsigned long xfer_mode;/* data transfer mode register */
        unsigned long sfis_cfg; /* SATA FIS reception config register */
} sil_port[] = {
        /* port 0 ... */
        /*   tf    ctl  bmdma  bmdma2  fifo    scr   sien   mode   sfis */
        {  0x80,  0x8A,   0x0,  0x10,  0x40, 0x100, 0x148,  0xb4, 0x14c },
        {  0xC0,  0xCA,   0x8,  0x18,  0x44, 0x180, 0x1c8,  0xf4, 0x1cc },
        { 0x280, 0x28A, 0x200, 0x210, 0x240, 0x300, 0x348, 0x2b4, 0x34c },
        { 0x2C0, 0x2CA, 0x208, 0x218, 0x244, 0x380, 0x3c8, 0x2f4, 0x3cc },
        /* ... port 3 */
};

MODULE_AUTHOR("Jeff Garzik");
MODULE_DESCRIPTION("low-level driver for Silicon Image SATA controller");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, sil_pci_tbl);
MODULE_VERSION(DRV_VERSION);

static int slow_down;
module_param(slow_down, int, 0444);
MODULE_PARM_DESC(slow_down, "Sledgehammer used to work around random problems, by limiting commands to 15 sectors (0=off, 1=on)");


static void sil_bmdma_stop(struct ata_queued_cmd *qc)
{
        struct ata_port *ap = qc->ap;
        void __iomem *mmio_base = ap->host->iomap[SIL_MMIO_BAR];
        void __iomem *bmdma2 = mmio_base + sil_port[ap->port_no].bmdma2;

        /* clear start/stop bit - can safely always write 0 */
        iowrite8(0, bmdma2);

        /* one-PIO-cycle guaranteed wait, per spec, for HDMA1:0 transition */
        ata_sff_dma_pause(ap);
}

static void sil_bmdma_setup(struct ata_queued_cmd *qc)
{
        struct ata_port *ap = qc->ap;
        void __iomem *bmdma = ap->ioaddr.bmdma_addr;

        /* load PRD table addr. */
        iowrite32(ap->bmdma_prd_dma, bmdma + ATA_DMA_TABLE_OFS);

        /* issue r/w command */
        ap->ops->sff_exec_command(ap, &qc->tf);
}

static void sil_bmdma_start(struct ata_queued_cmd *qc)
{
        unsigned int rw = (qc->tf.flags & ATA_TFLAG_WRITE);
        struct ata_port *ap = qc->ap;
        void __iomem *mmio_base = ap->host->iomap[SIL_MMIO_BAR];
        void __iomem *bmdma2 = mmio_base + sil_port[ap->port_no].bmdma2;
        u8 dmactl = ATA_DMA_START;

        /* set transfer direction, start host DMA transaction
           Note: For Large Block Transfer to work, the DMA must be started
           using the bmdma2 register. */
        if (!rw)
                dmactl |= ATA_DMA_WR;
        iowrite8(dmactl, bmdma2);
}

/* The way God intended PCI IDE scatter/gather lists to look and behave... */
static void sil_fill_sg(struct ata_queued_cmd *qc)
{
        struct scatterlist *sg;
        struct ata_port *ap = qc->ap;
        struct ata_bmdma_prd *prd, *last_prd = NULL;
        unsigned int si;

        prd = &ap->bmdma_prd[0];
        for_each_sg(qc->sg, sg, qc->n_elem, si) {
                /* Note h/w doesn't support 64-bit, so we unconditionally
                 * truncate dma_addr_t to u32.
                 */
                u32 addr = (u32) sg_dma_address(sg);
                u32 sg_len = sg_dma_len(sg);

                prd->addr = cpu_to_le32(addr);
                prd->flags_len = cpu_to_le32(sg_len);
                VPRINTK("PRD[%u] = (0x%X, 0x%X)\n", si, addr, sg_len);

                last_prd = prd;
                prd++;
        }

        if (likely(last_prd))
                last_prd->flags_len |= cpu_to_le32(ATA_PRD_EOT);
}

static void sil_qc_prep(struct ata_queued_cmd *qc)
{
        if (!(qc->flags & ATA_QCFLAG_DMAMAP))
                return;

        sil_fill_sg(qc);
}

static unsigned char sil_get_device_cache_line(struct pci_dev *pdev)
{
        u8 cache_line = 0;
        pci_read_config_byte(pdev, PCI_CACHE_LINE_SIZE, &cache_line);
        return cache_line;
}

/**
 *      sil_set_mode            -       wrap set_mode functions
 *      @link: link to set up
 *      @r_failed: returned device when we fail
 *
 *      Wrap the libata method for device setup as after the setup we need
 *      to inspect the results and do some configuration work
 */

static int sil_set_mode(struct ata_link *link, struct ata_device **r_failed)
{
        struct ata_port *ap = link->ap;
        void __iomem *mmio_base = ap->host->iomap[SIL_MMIO_BAR];
        void __iomem *addr = mmio_base + sil_port[ap->port_no].xfer_mode;
        struct ata_device *dev;
        u32 tmp, dev_mode[2] = { };
        int rc;

        rc = ata_do_set_mode(link, r_failed);
        if (rc)
                return rc;

        ata_for_each_dev(dev, link, ALL) {
                if (!ata_dev_enabled(dev))
                        dev_mode[dev->devno] = 0;       /* PIO0/1/2 */
                else if (dev->flags & ATA_DFLAG_PIO)
                        dev_mode[dev->devno] = 1;       /* PIO3/4 */
                else
                        dev_mode[dev->devno] = 3;       /* UDMA */
                /* value 2 indicates MDMA */
        }

        tmp = readl(addr);
        tmp &= ~((1<<5) | (1<<4) | (1<<1) | (1<<0));
        tmp |= dev_mode[0];
        tmp |= (dev_mode[1] << 4);
        writel(tmp, addr);
        readl(addr);    /* flush */
        return 0;
}

static inline void __iomem *sil_scr_addr(struct ata_port *ap,
                                         unsigned int sc_reg)
{
        void __iomem *offset = ap->ioaddr.scr_addr;

        switch (sc_reg) {
        case SCR_STATUS:
                return offset + 4;
        case SCR_ERROR:
                return offset + 8;
        case SCR_CONTROL:
                return offset;
        default:
                /* do nothing */
                break;
        }

        return NULL;
}

static int sil_scr_read(struct ata_link *link, unsigned int sc_reg, u32 *val)
{
        void __iomem *mmio = sil_scr_addr(link->ap, sc_reg);

        if (mmio) {
                *val = readl(mmio);
                return 0;
        }
        return -EINVAL;
}

static int sil_scr_write(struct ata_link *link, unsigned int sc_reg, u32 val)
{
        void __iomem *mmio = sil_scr_addr(link->ap, sc_reg);

        if (mmio) {
                writel(val, mmio);
                return 0;
        }
        return -EINVAL;
}

static void sil_host_intr(struct ata_port *ap, u32 bmdma2)
{
        struct ata_eh_info *ehi = &ap->link.eh_info;
        struct ata_queued_cmd *qc = ata_qc_from_tag(ap, ap->link.active_tag);
        u8 status;

        if (unlikely(bmdma2 & SIL_DMA_SATA_IRQ)) {
                u32 serror = 0xffffffff;

                /* SIEN doesn't mask SATA IRQs on some 3112s.  Those
                 * controllers continue to assert IRQ as long as
                 * SError bits are pending.  Clear SError immediately.
                 */
                sil_scr_read(&ap->link, SCR_ERROR, &serror);
                sil_scr_write(&ap->link, SCR_ERROR, serror);

                /* Sometimes spurious interrupts occur, double check
                 * it's PHYRDY CHG.
                 */
                if (serror & SERR_PHYRDY_CHG) {
                        ap->link.eh_info.serror |= serror;
                        goto freeze;
                }

                if (!(bmdma2 & SIL_DMA_COMPLETE))
                        return;
        }

        if (unlikely(!qc || (qc->tf.flags & ATA_TFLAG_POLLING))) {
                /* this sometimes happens, just clear IRQ */
                ap->ops->sff_check_status(ap);
                return;
        }

        /* Check whether we are expecting interrupt in this state */
        switch (ap->hsm_task_state) {
        case HSM_ST_FIRST:
                /* Some pre-ATAPI-4 devices assert INTRQ
                 * at this state when ready to receive CDB.
                 */

                /* Check the ATA_DFLAG_CDB_INTR flag is enough here.
                 * The flag was turned on only for atapi devices.  No
                 * need to check ata_is_atapi(qc->tf.protocol) again.
                 */
                if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
                        goto err_hsm;
                break;
        case HSM_ST_LAST:
                if (ata_is_dma(qc->tf.protocol)) {
                        /* clear DMA-Start bit */
                        ap->ops->bmdma_stop(qc);

                        if (bmdma2 & SIL_DMA_ERROR) {
                                qc->err_mask |= AC_ERR_HOST_BUS;
                                ap->hsm_task_state = HSM_ST_ERR;
                        }
                }
                break;
        case HSM_ST:
                break;
        default:
                goto err_hsm;
        }

        /* check main status, clearing INTRQ */
        status = ap->ops->sff_check_status(ap);
        if (unlikely(status & ATA_BUSY))
                goto err_hsm;

        /* ack bmdma irq events */
        ata_bmdma_irq_clear(ap);

        /* kick HSM in the ass */
        ata_sff_hsm_move(ap, qc, status, 0);

        if (unlikely(qc->err_mask) && ata_is_dma(qc->tf.protocol))
                ata_ehi_push_desc(ehi, "BMDMA2 stat 0x%x", bmdma2);

        return;

 err_hsm:
        qc->err_mask |= AC_ERR_HSM;
 freeze:
        ata_port_freeze(ap);
}

static irqreturn_t sil_interrupt(int irq, void *dev_instance)
{
        struct ata_host *host = dev_instance;
        void __iomem *mmio_base = host->iomap[SIL_MMIO_BAR];
        int handled = 0;
        int i;

        spin_lock(&host->lock);

        for (i = 0; i < host->n_ports; i++) {
                struct ata_port *ap = host->ports[i];
                u32 bmdma2 = readl(mmio_base + sil_port[ap->port_no].bmdma2);

                /* turn off SATA_IRQ if not supported */
                if (ap->flags & SIL_FLAG_NO_SATA_IRQ)
                        bmdma2 &= ~SIL_DMA_SATA_IRQ;

                if (bmdma2 == 0xffffffff ||
                    !(bmdma2 & (SIL_DMA_COMPLETE | SIL_DMA_SATA_IRQ)))
                        continue;

                sil_host_intr(ap, bmdma2);
                handled = 1;
        }

        spin_unlock(&host->lock);

        return IRQ_RETVAL(handled);
}

static void sil_freeze(struct ata_port *ap)
{
        void __iomem *mmio_base = ap->host->iomap[SIL_MMIO_BAR];
        u32 tmp;

        /* global IRQ mask doesn't block SATA IRQ, turn off explicitly */
        writel(0, mmio_base + sil_port[ap->port_no].sien);

        /* plug IRQ */
        tmp = readl(mmio_base + SIL_SYSCFG);
        tmp |= SIL_MASK_IDE0_INT << ap->port_no;
        writel(tmp, mmio_base + SIL_SYSCFG);
        readl(mmio_base + SIL_SYSCFG);  /* flush */

        /* Ensure DMA_ENABLE is off.
         *
         * This is because the controller will not give us access to the
         * taskfile registers while a DMA is in progress
         */
        iowrite8(ioread8(ap->ioaddr.bmdma_addr) & ~SIL_DMA_ENABLE,
                 ap->ioaddr.bmdma_addr);

        /* According to ata_bmdma_stop, an HDMA transition requires
         * on PIO cycle. But we can't read a taskfile register.
         */
        ioread8(ap->ioaddr.bmdma_addr);
}

static void sil_thaw(struct ata_port *ap)
{
        void __iomem *mmio_base = ap->host->iomap[SIL_MMIO_BAR];
        u32 tmp;

        /* clear IRQ */
        ap->ops->sff_check_status(ap);
        ata_bmdma_irq_clear(ap);

        /* turn on SATA IRQ if supported */
        if (!(ap->flags & SIL_FLAG_NO_SATA_IRQ))
                writel(SIL_SIEN_N, mmio_base + sil_port[ap->port_no].sien);

        /* turn on IRQ */
        tmp = readl(mmio_base + SIL_SYSCFG);
        tmp &= ~(SIL_MASK_IDE0_INT << ap->port_no);
        writel(tmp, mmio_base + SIL_SYSCFG);
}

/**
 *      sil_dev_config - Apply device/host-specific errata fixups
 *      @dev: Device to be examined
 *
 *      After the IDENTIFY [PACKET] DEVICE step is complete, and a
 *      device is known to be present, this function is called.
 *      We apply two errata fixups which are specific to Silicon Image,
 *      a Seagate and a Maxtor fixup.
 *
 *      For certain Seagate devices, we must limit the maximum sectors
 *      to under 8K.
 *
 *      For certain Maxtor devices, we must not program the drive
 *      beyond udma5.
 *
 *      Both fixups are unfairly pessimistic.  As soon as I get more
 *      information on these errata, I will create a more exhaustive
 *      list, and apply the fixups to only the specific
 *      devices/hosts/firmwares that need it.
 *
 *      20040111 - Seagate drives affected by the Mod15Write bug are blacklisted
 *      The Maxtor quirk is in the blacklist, but I'm keeping the original
 *      pessimistic fix for the following reasons...
 *      - There seems to be less info on it, only one device gleaned off the
 *      Windows driver, maybe only one is affected.  More info would be greatly
 *      appreciated.
 *      - But then again UDMA5 is hardly anything to complain about
 */
static void sil_dev_config(struct ata_device *dev)
{
        struct ata_port *ap = dev->link->ap;
        int print_info = ap->link.eh_context.i.flags & ATA_EHI_PRINTINFO;
        unsigned int n, quirks = 0;
        unsigned char model_num[ATA_ID_PROD_LEN + 1];

        /* This controller doesn't support trim */
        dev->horkage |= ATA_HORKAGE_NOTRIM;

        ata_id_c_string(dev->id, model_num, ATA_ID_PROD, sizeof(model_num));

        for (n = 0; sil_blacklist[n].product; n++)
                if (!strcmp(sil_blacklist[n].product, model_num)) {
                        quirks = sil_blacklist[n].quirk;
                        break;
                }

        /* limit requests to 15 sectors */
        if (slow_down ||
            ((ap->flags & SIL_FLAG_MOD15WRITE) &&
             (quirks & SIL_QUIRK_MOD15WRITE))) {
                if (print_info)
                        ata_dev_info(dev,
                "applying Seagate errata fix (mod15write workaround)\n");
                dev->max_sectors = 15;
                return;
        }

        /* limit to udma5 */
        if (quirks & SIL_QUIRK_UDMA5MAX) {
                if (print_info)
                        ata_dev_info(dev, "applying Maxtor errata fix %s\n",
                                     model_num);
                dev->udma_mask &= ATA_UDMA5;
                return;
        }
}

static void sil_init_controller(struct ata_host *host)
{
        struct pci_dev *pdev = to_pci_dev(host->dev);
        void __iomem *mmio_base = host->iomap[SIL_MMIO_BAR];
        u8 cls;
        u32 tmp;
        int i;

        /* Initialize FIFO PCI bus arbitration */
        cls = sil_get_device_cache_line(pdev);
        if (cls) {
                cls >>= 3;
                cls++;  /* cls = (line_size/8)+1 */
                for (i = 0; i < host->n_ports; i++)
                        writew(cls << 8 | cls,
                               mmio_base + sil_port[i].fifo_cfg);
        } else
                dev_warn(&pdev->dev,
                         "cache line size not set.  Driver may not function\n");

        /* Apply R_ERR on DMA activate FIS errata workaround */
        if (host->ports[0]->flags & SIL_FLAG_RERR_ON_DMA_ACT) {
                int cnt;

                for (i = 0, cnt = 0; i < host->n_ports; i++) {
                        tmp = readl(mmio_base + sil_port[i].sfis_cfg);
                        if ((tmp & 0x3) != 0x01)
                                continue;
                        if (!cnt)
                                dev_info(&pdev->dev,
                                         "Applying R_ERR on DMA activate FIS errata fix\n");
                        writel(tmp & ~0x3, mmio_base + sil_port[i].sfis_cfg);
                        cnt++;
                }
        }

        if (host->n_ports == 4) {
                /* flip the magic "make 4 ports work" bit */
                tmp = readl(mmio_base + sil_port[2].bmdma);
                if ((tmp & SIL_INTR_STEERING) == 0)
                        writel(tmp | SIL_INTR_STEERING,
                               mmio_base + sil_port[2].bmdma);
        }
}

static bool sil_broken_system_poweroff(struct pci_dev *pdev)
{
        static const struct dmi_system_id broken_systems[] = {
                {
                        .ident = "HP Compaq nx6325",
                        .matches = {
                                DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
                                DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq nx6325"),
                        },
                        /* PCI slot number of the controller */
                        .driver_data = (void *)0x12UL,
                },

                { }     /* terminate list */
        };
        const struct dmi_system_id *dmi = dmi_first_match(broken_systems);

        if (dmi) {
                unsigned long slot = (unsigned long)dmi->driver_data;
                /* apply the quirk only to on-board controllers */
                return slot == PCI_SLOT(pdev->devfn);
        }

        return false;
}

static int sil_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
{
        int board_id = ent->driver_data;
        struct ata_port_info pi = sil_port_info[board_id];
        const struct ata_port_info *ppi[] = { &pi, NULL };
        struct ata_host *host;
        void __iomem *mmio_base;
        int n_ports, rc;
        unsigned int i;

        ata_print_version_once(&pdev->dev, DRV_VERSION);

        /* allocate host */
        n_ports = 2;
        if (board_id == sil_3114)
                n_ports = 4;

        if (sil_broken_system_poweroff(pdev)) {
                pi.flags |= ATA_FLAG_NO_POWEROFF_SPINDOWN |
                                        ATA_FLAG_NO_HIBERNATE_SPINDOWN;
                dev_info(&pdev->dev, "quirky BIOS, skipping spindown "
                                "on poweroff and hibernation\n");
        }

        host = ata_host_alloc_pinfo(&pdev->dev, ppi, n_ports);
        if (!host)
                return -ENOMEM;

        /* acquire resources and fill host */
        rc = pcim_enable_device(pdev);
        if (rc)
                return rc;

        rc = pcim_iomap_regions(pdev, 1 << SIL_MMIO_BAR, DRV_NAME);
        if (rc == -EBUSY)
                pcim_pin_device(pdev);
        if (rc)
                return rc;
        host->iomap = pcim_iomap_table(pdev);

        rc = dma_set_mask(&pdev->dev, ATA_DMA_MASK);
        if (rc)
                return rc;
        rc = dma_set_coherent_mask(&pdev->dev, ATA_DMA_MASK);
        if (rc)
                return rc;

        mmio_base = host->iomap[SIL_MMIO_BAR];

        for (i = 0; i < host->n_ports; i++) {
                struct ata_port *ap = host->ports[i];
                struct ata_ioports *ioaddr = &ap->ioaddr;

                ioaddr->cmd_addr = mmio_base + sil_port[i].tf;
                ioaddr->altstatus_addr =
                ioaddr->ctl_addr = mmio_base + sil_port[i].ctl;
                ioaddr->bmdma_addr = mmio_base + sil_port[i].bmdma;
                ioaddr->scr_addr = mmio_base + sil_port[i].scr;
                ata_sff_std_ports(ioaddr);

                ata_port_pbar_desc(ap, SIL_MMIO_BAR, -1, "mmio");
                ata_port_pbar_desc(ap, SIL_MMIO_BAR, sil_port[i].tf, "tf");
        }

        /* initialize and activate */
        sil_init_controller(host);

        pci_set_master(pdev);
        return ata_host_activate(host, pdev->irq, sil_interrupt, IRQF_SHARED,
                                 &sil_sht);
}

#ifdef CONFIG_PM_SLEEP
static int sil_pci_device_resume(struct pci_dev *pdev)
{
        struct ata_host *host = pci_get_drvdata(pdev);
        int rc;

        rc = ata_pci_device_do_resume(pdev);
        if (rc)
                return rc;

        sil_init_controller(host);
        ata_host_resume(host);

        return 0;
}
#endif

module_pci_driver(sil_pci_driver);