libata: kill dead code paths in reset path

[linux-2.6] / drivers / ata / ahci.c

/*
 *  ahci.c - AHCI SATA support
 *
 *  Maintained by:  Jeff Garzik <jgarzik@pobox.com>
 *                  Please ALWAYS copy linux-ide@vger.kernel.org
 *                  on emails.
 *
 *  Copyright 2004-2005 Red Hat, Inc.
 *
 *
 *  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/DocBook/libata.*
 *
 * AHCI hardware documentation:
 * http://www.intel.com/technology/serialata/pdf/rev1_0.pdf
 * http://www.intel.com/technology/serialata/pdf/rev1_1.pdf
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/dma-mapping.h>
#include <linux/device.h>
#include <linux/dmi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_cmnd.h>
#include <linux/libata.h>

#define DRV_NAME        "ahci"
#define DRV_VERSION     "3.0"

static int ahci_skip_host_reset;
module_param_named(skip_host_reset, ahci_skip_host_reset, int, 0444);
MODULE_PARM_DESC(skip_host_reset, "skip global host reset (0=don't skip, 1=skip)");

static int ahci_enable_alpm(struct ata_port *ap,
                enum link_pm policy);
static void ahci_disable_alpm(struct ata_port *ap);

enum {
        AHCI_PCI_BAR            = 5,
        AHCI_MAX_PORTS          = 32,
        AHCI_MAX_SG             = 168, /* hardware max is 64K */
        AHCI_DMA_BOUNDARY       = 0xffffffff,
        AHCI_MAX_CMDS           = 32,
        AHCI_CMD_SZ             = 32,
        AHCI_CMD_SLOT_SZ        = AHCI_MAX_CMDS * AHCI_CMD_SZ,
        AHCI_RX_FIS_SZ          = 256,
        AHCI_CMD_TBL_CDB        = 0x40,
        AHCI_CMD_TBL_HDR_SZ     = 0x80,
        AHCI_CMD_TBL_SZ         = AHCI_CMD_TBL_HDR_SZ + (AHCI_MAX_SG * 16),
        AHCI_CMD_TBL_AR_SZ      = AHCI_CMD_TBL_SZ * AHCI_MAX_CMDS,
        AHCI_PORT_PRIV_DMA_SZ   = AHCI_CMD_SLOT_SZ + AHCI_CMD_TBL_AR_SZ +
                                  AHCI_RX_FIS_SZ,
        AHCI_IRQ_ON_SG          = (1 << 31),
        AHCI_CMD_ATAPI          = (1 << 5),
        AHCI_CMD_WRITE          = (1 << 6),
        AHCI_CMD_PREFETCH       = (1 << 7),
        AHCI_CMD_RESET          = (1 << 8),
        AHCI_CMD_CLR_BUSY       = (1 << 10),

        RX_FIS_D2H_REG          = 0x40, /* offset of D2H Register FIS data */
        RX_FIS_SDB              = 0x58, /* offset of SDB FIS data */
        RX_FIS_UNK              = 0x60, /* offset of Unknown FIS data */

        board_ahci              = 0,
        board_ahci_vt8251       = 1,
        board_ahci_ign_iferr    = 2,
        board_ahci_sb600        = 3,
        board_ahci_mv           = 4,
        board_ahci_sb700        = 5,

        /* global controller registers */
        HOST_CAP                = 0x00, /* host capabilities */
        HOST_CTL                = 0x04, /* global host control */
        HOST_IRQ_STAT           = 0x08, /* interrupt status */
        HOST_PORTS_IMPL         = 0x0c, /* bitmap of implemented ports */
        HOST_VERSION            = 0x10, /* AHCI spec. version compliancy */

        /* HOST_CTL bits */
        HOST_RESET              = (1 << 0),  /* reset controller; self-clear */
        HOST_IRQ_EN             = (1 << 1),  /* global IRQ enable */
        HOST_AHCI_EN            = (1 << 31), /* AHCI enabled */

        /* HOST_CAP bits */
        HOST_CAP_SSC            = (1 << 14), /* Slumber capable */
        HOST_CAP_PMP            = (1 << 17), /* Port Multiplier support */
        HOST_CAP_CLO            = (1 << 24), /* Command List Override support */
        HOST_CAP_ALPM           = (1 << 26), /* Aggressive Link PM support */
        HOST_CAP_SSS            = (1 << 27), /* Staggered Spin-up */
        HOST_CAP_SNTF           = (1 << 29), /* SNotification register */
        HOST_CAP_NCQ            = (1 << 30), /* Native Command Queueing */
        HOST_CAP_64             = (1 << 31), /* PCI DAC (64-bit DMA) support */

        /* registers for each SATA port */
        PORT_LST_ADDR           = 0x00, /* command list DMA addr */
        PORT_LST_ADDR_HI        = 0x04, /* command list DMA addr hi */
        PORT_FIS_ADDR           = 0x08, /* FIS rx buf addr */
        PORT_FIS_ADDR_HI        = 0x0c, /* FIS rx buf addr hi */
        PORT_IRQ_STAT           = 0x10, /* interrupt status */
        PORT_IRQ_MASK           = 0x14, /* interrupt enable/disable mask */
        PORT_CMD                = 0x18, /* port command */
        PORT_TFDATA             = 0x20, /* taskfile data */
        PORT_SIG                = 0x24, /* device TF signature */
        PORT_CMD_ISSUE          = 0x38, /* command issue */
        PORT_SCR_STAT           = 0x28, /* SATA phy register: SStatus */
        PORT_SCR_CTL            = 0x2c, /* SATA phy register: SControl */
        PORT_SCR_ERR            = 0x30, /* SATA phy register: SError */
        PORT_SCR_ACT            = 0x34, /* SATA phy register: SActive */
        PORT_SCR_NTF            = 0x3c, /* SATA phy register: SNotification */

        /* PORT_IRQ_{STAT,MASK} bits */
        PORT_IRQ_COLD_PRES      = (1 << 31), /* cold presence detect */
        PORT_IRQ_TF_ERR         = (1 << 30), /* task file error */
        PORT_IRQ_HBUS_ERR       = (1 << 29), /* host bus fatal error */
        PORT_IRQ_HBUS_DATA_ERR  = (1 << 28), /* host bus data error */
        PORT_IRQ_IF_ERR         = (1 << 27), /* interface fatal error */
        PORT_IRQ_IF_NONFATAL    = (1 << 26), /* interface non-fatal error */
        PORT_IRQ_OVERFLOW       = (1 << 24), /* xfer exhausted available S/G */
        PORT_IRQ_BAD_PMP        = (1 << 23), /* incorrect port multiplier */

        PORT_IRQ_PHYRDY         = (1 << 22), /* PhyRdy changed */
        PORT_IRQ_DEV_ILCK       = (1 << 7), /* device interlock */
        PORT_IRQ_CONNECT        = (1 << 6), /* port connect change status */
        PORT_IRQ_SG_DONE        = (1 << 5), /* descriptor processed */
        PORT_IRQ_UNK_FIS        = (1 << 4), /* unknown FIS rx'd */
        PORT_IRQ_SDB_FIS        = (1 << 3), /* Set Device Bits FIS rx'd */
        PORT_IRQ_DMAS_FIS       = (1 << 2), /* DMA Setup FIS rx'd */
        PORT_IRQ_PIOS_FIS       = (1 << 1), /* PIO Setup FIS rx'd */
        PORT_IRQ_D2H_REG_FIS    = (1 << 0), /* D2H Register FIS rx'd */

        PORT_IRQ_FREEZE         = PORT_IRQ_HBUS_ERR |
                                  PORT_IRQ_IF_ERR |
                                  PORT_IRQ_CONNECT |
                                  PORT_IRQ_PHYRDY |
                                  PORT_IRQ_UNK_FIS |
                                  PORT_IRQ_BAD_PMP,
        PORT_IRQ_ERROR          = PORT_IRQ_FREEZE |
                                  PORT_IRQ_TF_ERR |
                                  PORT_IRQ_HBUS_DATA_ERR,
        DEF_PORT_IRQ            = PORT_IRQ_ERROR | PORT_IRQ_SG_DONE |
                                  PORT_IRQ_SDB_FIS | PORT_IRQ_DMAS_FIS |
                                  PORT_IRQ_PIOS_FIS | PORT_IRQ_D2H_REG_FIS,

        /* PORT_CMD bits */
        PORT_CMD_ASP            = (1 << 27), /* Aggressive Slumber/Partial */
        PORT_CMD_ALPE           = (1 << 26), /* Aggressive Link PM enable */
        PORT_CMD_ATAPI          = (1 << 24), /* Device is ATAPI */
        PORT_CMD_PMP            = (1 << 17), /* PMP attached */
        PORT_CMD_LIST_ON        = (1 << 15), /* cmd list DMA engine running */
        PORT_CMD_FIS_ON         = (1 << 14), /* FIS DMA engine running */
        PORT_CMD_FIS_RX         = (1 << 4), /* Enable FIS receive DMA engine */
        PORT_CMD_CLO            = (1 << 3), /* Command list override */
        PORT_CMD_POWER_ON       = (1 << 2), /* Power up device */
        PORT_CMD_SPIN_UP        = (1 << 1), /* Spin up device */
        PORT_CMD_START          = (1 << 0), /* Enable port DMA engine */

        PORT_CMD_ICC_MASK       = (0xf << 28), /* i/f ICC state mask */
        PORT_CMD_ICC_ACTIVE     = (0x1 << 28), /* Put i/f in active state */
        PORT_CMD_ICC_PARTIAL    = (0x2 << 28), /* Put i/f in partial state */
        PORT_CMD_ICC_SLUMBER    = (0x6 << 28), /* Put i/f in slumber state */

        /* hpriv->flags bits */
        AHCI_HFLAG_NO_NCQ               = (1 << 0),
        AHCI_HFLAG_IGN_IRQ_IF_ERR       = (1 << 1), /* ignore IRQ_IF_ERR */
        AHCI_HFLAG_IGN_SERR_INTERNAL    = (1 << 2), /* ignore SERR_INTERNAL */
        AHCI_HFLAG_32BIT_ONLY           = (1 << 3), /* force 32bit */
        AHCI_HFLAG_MV_PATA              = (1 << 4), /* PATA port */
        AHCI_HFLAG_NO_MSI               = (1 << 5), /* no PCI MSI */
        AHCI_HFLAG_NO_PMP               = (1 << 6), /* no PMP */
        AHCI_HFLAG_NO_HOTPLUG           = (1 << 7), /* ignore PxSERR.DIAG.N */
        AHCI_HFLAG_SECT255              = (1 << 8), /* max 255 sectors */

        /* ap->flags bits */

        AHCI_FLAG_COMMON                = ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
                                          ATA_FLAG_MMIO | ATA_FLAG_PIO_DMA |
                                          ATA_FLAG_ACPI_SATA | ATA_FLAG_AN |
                                          ATA_FLAG_IPM,

        ICH_MAP                         = 0x90, /* ICH MAP register */
};

struct ahci_cmd_hdr {
        __le32                  opts;
        __le32                  status;
        __le32                  tbl_addr;
        __le32                  tbl_addr_hi;
        __le32                  reserved[4];
};

struct ahci_sg {
        __le32                  addr;
        __le32                  addr_hi;
        __le32                  reserved;
        __le32                  flags_size;
};

struct ahci_host_priv {
        unsigned int            flags;          /* AHCI_HFLAG_* */
        u32                     cap;            /* cap to use */
        u32                     port_map;       /* port map to use */
        u32                     saved_cap;      /* saved initial cap */
        u32                     saved_port_map; /* saved initial port_map */
};

struct ahci_port_priv {
        struct ata_link         *active_link;
        struct ahci_cmd_hdr     *cmd_slot;
        dma_addr_t              cmd_slot_dma;
        void                    *cmd_tbl;
        dma_addr_t              cmd_tbl_dma;
        void                    *rx_fis;
        dma_addr_t              rx_fis_dma;
        /* for NCQ spurious interrupt analysis */
        unsigned int            ncq_saw_d2h:1;
        unsigned int            ncq_saw_dmas:1;
        unsigned int            ncq_saw_sdb:1;
        u32                     intr_mask;      /* interrupts to enable */
};

static int ahci_scr_read(struct ata_port *ap, unsigned int sc_reg, u32 *val);
static int ahci_scr_write(struct ata_port *ap, unsigned int sc_reg, u32 val);
static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent);
static unsigned int ahci_qc_issue(struct ata_queued_cmd *qc);
static bool ahci_qc_fill_rtf(struct ata_queued_cmd *qc);
static int ahci_port_start(struct ata_port *ap);
static void ahci_port_stop(struct ata_port *ap);
static void ahci_qc_prep(struct ata_queued_cmd *qc);
static void ahci_freeze(struct ata_port *ap);
static void ahci_thaw(struct ata_port *ap);
static void ahci_pmp_attach(struct ata_port *ap);
static void ahci_pmp_detach(struct ata_port *ap);
static int ahci_softreset(struct ata_link *link, unsigned int *class,
                          unsigned long deadline);
static int ahci_hardreset(struct ata_link *link, unsigned int *class,
                          unsigned long deadline);
static int ahci_vt8251_hardreset(struct ata_link *link, unsigned int *class,
                                 unsigned long deadline);
static int ahci_p5wdh_hardreset(struct ata_link *link, unsigned int *class,
                                unsigned long deadline);
static void ahci_postreset(struct ata_link *link, unsigned int *class);
static void ahci_error_handler(struct ata_port *ap);
static void ahci_post_internal_cmd(struct ata_queued_cmd *qc);
static int ahci_port_resume(struct ata_port *ap);
static void ahci_dev_config(struct ata_device *dev);
static unsigned int ahci_fill_sg(struct ata_queued_cmd *qc, void *cmd_tbl);
static void ahci_fill_cmd_slot(struct ahci_port_priv *pp, unsigned int tag,
                               u32 opts);
#ifdef CONFIG_PM
static int ahci_port_suspend(struct ata_port *ap, pm_message_t mesg);
static int ahci_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg);
static int ahci_pci_device_resume(struct pci_dev *pdev);
#endif

static struct class_device_attribute *ahci_shost_attrs[] = {
        &class_device_attr_link_power_management_policy,
        NULL
};

static struct scsi_host_template ahci_sht = {
        ATA_NCQ_SHT(DRV_NAME),
        .can_queue              = AHCI_MAX_CMDS - 1,
        .sg_tablesize           = AHCI_MAX_SG,
        .dma_boundary           = AHCI_DMA_BOUNDARY,
        .shost_attrs            = ahci_shost_attrs,
};

static struct ata_port_operations ahci_ops = {
        .inherits               = &sata_pmp_port_ops,

        .qc_defer               = sata_pmp_qc_defer_cmd_switch,
        .qc_prep                = ahci_qc_prep,
        .qc_issue               = ahci_qc_issue,
        .qc_fill_rtf            = ahci_qc_fill_rtf,

        .freeze                 = ahci_freeze,
        .thaw                   = ahci_thaw,
        .softreset              = ahci_softreset,
        .hardreset              = ahci_hardreset,
        .postreset              = ahci_postreset,
        .pmp_softreset          = ahci_softreset,
        .error_handler          = ahci_error_handler,
        .post_internal_cmd      = ahci_post_internal_cmd,
        .dev_config             = ahci_dev_config,

        .scr_read               = ahci_scr_read,
        .scr_write              = ahci_scr_write,
        .pmp_attach             = ahci_pmp_attach,
        .pmp_detach             = ahci_pmp_detach,

        .enable_pm              = ahci_enable_alpm,
        .disable_pm             = ahci_disable_alpm,
#ifdef CONFIG_PM
        .port_suspend           = ahci_port_suspend,
        .port_resume            = ahci_port_resume,
#endif
        .port_start             = ahci_port_start,
        .port_stop              = ahci_port_stop,
};

static struct ata_port_operations ahci_vt8251_ops = {
        .inherits               = &ahci_ops,
        .hardreset              = ahci_vt8251_hardreset,
};

static struct ata_port_operations ahci_p5wdh_ops = {
        .inherits               = &ahci_ops,
        .hardreset              = ahci_p5wdh_hardreset,
};

#define AHCI_HFLAGS(flags)      .private_data   = (void *)(flags)

static const struct ata_port_info ahci_port_info[] = {
        /* board_ahci */
        {
                .flags          = AHCI_FLAG_COMMON,
                .pio_mask       = 0x1f, /* pio0-4 */
                .udma_mask      = ATA_UDMA6,
                .port_ops       = &ahci_ops,
        },
        /* board_ahci_vt8251 */
        {
                AHCI_HFLAGS     (AHCI_HFLAG_NO_NCQ | AHCI_HFLAG_NO_PMP),
                .flags          = AHCI_FLAG_COMMON,
                .pio_mask       = 0x1f, /* pio0-4 */
                .udma_mask      = ATA_UDMA6,
                .port_ops       = &ahci_vt8251_ops,
        },
        /* board_ahci_ign_iferr */
        {
                AHCI_HFLAGS     (AHCI_HFLAG_IGN_IRQ_IF_ERR),
                .flags          = AHCI_FLAG_COMMON,
                .pio_mask       = 0x1f, /* pio0-4 */
                .udma_mask      = ATA_UDMA6,
                .port_ops       = &ahci_ops,
        },
        /* board_ahci_sb600 */
        {
                AHCI_HFLAGS     (AHCI_HFLAG_IGN_SERR_INTERNAL |
                                 AHCI_HFLAG_32BIT_ONLY |
                                 AHCI_HFLAG_SECT255 | AHCI_HFLAG_NO_PMP),
                .flags          = AHCI_FLAG_COMMON,
                .pio_mask       = 0x1f, /* pio0-4 */
                .udma_mask      = ATA_UDMA6,
                .port_ops       = &ahci_ops,
        },
        /* board_ahci_mv */
        {
                AHCI_HFLAGS     (AHCI_HFLAG_NO_NCQ | AHCI_HFLAG_NO_MSI |
                                 AHCI_HFLAG_MV_PATA),
                .flags          = ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
                                  ATA_FLAG_MMIO | ATA_FLAG_PIO_DMA,
                .pio_mask       = 0x1f, /* pio0-4 */
                .udma_mask      = ATA_UDMA6,
                .port_ops       = &ahci_ops,
        },
        /* board_ahci_sb700 */
        {
                AHCI_HFLAGS     (AHCI_HFLAG_IGN_SERR_INTERNAL |
                                 AHCI_HFLAG_NO_PMP),
                .flags          = AHCI_FLAG_COMMON,
                .pio_mask       = 0x1f, /* pio0-4 */
                .udma_mask      = ATA_UDMA6,
                .port_ops       = &ahci_ops,
        },
};

static const struct pci_device_id ahci_pci_tbl[] = {
        /* Intel */
        { PCI_VDEVICE(INTEL, 0x2652), board_ahci }, /* ICH6 */
        { PCI_VDEVICE(INTEL, 0x2653), board_ahci }, /* ICH6M */
        { PCI_VDEVICE(INTEL, 0x27c1), board_ahci }, /* ICH7 */
        { PCI_VDEVICE(INTEL, 0x27c5), board_ahci }, /* ICH7M */
        { PCI_VDEVICE(INTEL, 0x27c3), board_ahci }, /* ICH7R */
        { PCI_VDEVICE(AL, 0x5288), board_ahci_ign_iferr }, /* ULi M5288 */
        { PCI_VDEVICE(INTEL, 0x2681), board_ahci }, /* ESB2 */
        { PCI_VDEVICE(INTEL, 0x2682), board_ahci }, /* ESB2 */
        { PCI_VDEVICE(INTEL, 0x2683), board_ahci }, /* ESB2 */
        { PCI_VDEVICE(INTEL, 0x27c6), board_ahci }, /* ICH7-M DH */
        { PCI_VDEVICE(INTEL, 0x2821), board_ahci }, /* ICH8 */
        { PCI_VDEVICE(INTEL, 0x2822), board_ahci }, /* ICH8 */
        { PCI_VDEVICE(INTEL, 0x2824), board_ahci }, /* ICH8 */
        { PCI_VDEVICE(INTEL, 0x2829), board_ahci }, /* ICH8M */
        { PCI_VDEVICE(INTEL, 0x282a), board_ahci }, /* ICH8M */
        { PCI_VDEVICE(INTEL, 0x2922), board_ahci }, /* ICH9 */
        { PCI_VDEVICE(INTEL, 0x2923), board_ahci }, /* ICH9 */
        { PCI_VDEVICE(INTEL, 0x2924), board_ahci }, /* ICH9 */
        { PCI_VDEVICE(INTEL, 0x2925), board_ahci }, /* ICH9 */
        { PCI_VDEVICE(INTEL, 0x2927), board_ahci }, /* ICH9 */
        { PCI_VDEVICE(INTEL, 0x2929), board_ahci }, /* ICH9M */
        { PCI_VDEVICE(INTEL, 0x292a), board_ahci }, /* ICH9M */
        { PCI_VDEVICE(INTEL, 0x292b), board_ahci }, /* ICH9M */
        { PCI_VDEVICE(INTEL, 0x292c), board_ahci }, /* ICH9M */
        { PCI_VDEVICE(INTEL, 0x292f), board_ahci }, /* ICH9M */
        { PCI_VDEVICE(INTEL, 0x294d), board_ahci }, /* ICH9 */
        { PCI_VDEVICE(INTEL, 0x294e), board_ahci }, /* ICH9M */
        { PCI_VDEVICE(INTEL, 0x502a), board_ahci }, /* Tolapai */
        { PCI_VDEVICE(INTEL, 0x502b), board_ahci }, /* Tolapai */
        { PCI_VDEVICE(INTEL, 0x3a05), board_ahci }, /* ICH10 */
        { PCI_VDEVICE(INTEL, 0x3a25), board_ahci }, /* ICH10 */

        /* JMicron 360/1/3/5/6, match class to avoid IDE function */
        { PCI_VENDOR_ID_JMICRON, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
          PCI_CLASS_STORAGE_SATA_AHCI, 0xffffff, board_ahci_ign_iferr },

        /* ATI */
        { PCI_VDEVICE(ATI, 0x4380), board_ahci_sb600 }, /* ATI SB600 */
        { PCI_VDEVICE(ATI, 0x4390), board_ahci_sb700 }, /* ATI SB700/800 */
        { PCI_VDEVICE(ATI, 0x4391), board_ahci_sb700 }, /* ATI SB700/800 */
        { PCI_VDEVICE(ATI, 0x4392), board_ahci_sb700 }, /* ATI SB700/800 */
        { PCI_VDEVICE(ATI, 0x4393), board_ahci_sb700 }, /* ATI SB700/800 */
        { PCI_VDEVICE(ATI, 0x4394), board_ahci_sb700 }, /* ATI SB700/800 */
        { PCI_VDEVICE(ATI, 0x4395), board_ahci_sb700 }, /* ATI SB700/800 */

        /* VIA */
        { PCI_VDEVICE(VIA, 0x3349), board_ahci_vt8251 }, /* VIA VT8251 */
        { PCI_VDEVICE(VIA, 0x6287), board_ahci_vt8251 }, /* VIA VT8251 */

        /* NVIDIA */
        { PCI_VDEVICE(NVIDIA, 0x044c), board_ahci },            /* MCP65 */
        { PCI_VDEVICE(NVIDIA, 0x044d), board_ahci },            /* MCP65 */
        { PCI_VDEVICE(NVIDIA, 0x044e), board_ahci },            /* MCP65 */
        { PCI_VDEVICE(NVIDIA, 0x044f), board_ahci },            /* MCP65 */
        { PCI_VDEVICE(NVIDIA, 0x045c), board_ahci },            /* MCP65 */
        { PCI_VDEVICE(NVIDIA, 0x045d), board_ahci },            /* MCP65 */
        { PCI_VDEVICE(NVIDIA, 0x045e), board_ahci },            /* MCP65 */
        { PCI_VDEVICE(NVIDIA, 0x045f), board_ahci },            /* MCP65 */
        { PCI_VDEVICE(NVIDIA, 0x0550), board_ahci },            /* MCP67 */
        { PCI_VDEVICE(NVIDIA, 0x0551), board_ahci },            /* MCP67 */
        { PCI_VDEVICE(NVIDIA, 0x0552), board_ahci },            /* MCP67 */
        { PCI_VDEVICE(NVIDIA, 0x0553), board_ahci },            /* MCP67 */
        { PCI_VDEVICE(NVIDIA, 0x0554), board_ahci },            /* MCP67 */
        { PCI_VDEVICE(NVIDIA, 0x0555), board_ahci },            /* MCP67 */
        { PCI_VDEVICE(NVIDIA, 0x0556), board_ahci },            /* MCP67 */
        { PCI_VDEVICE(NVIDIA, 0x0557), board_ahci },            /* MCP67 */
        { PCI_VDEVICE(NVIDIA, 0x0558), board_ahci },            /* MCP67 */
        { PCI_VDEVICE(NVIDIA, 0x0559), board_ahci },            /* MCP67 */
        { PCI_VDEVICE(NVIDIA, 0x055a), board_ahci },            /* MCP67 */
        { PCI_VDEVICE(NVIDIA, 0x055b), board_ahci },            /* MCP67 */
        { PCI_VDEVICE(NVIDIA, 0x07f0), board_ahci },            /* MCP73 */
        { PCI_VDEVICE(NVIDIA, 0x07f1), board_ahci },            /* MCP73 */
        { PCI_VDEVICE(NVIDIA, 0x07f2), board_ahci },            /* MCP73 */
        { PCI_VDEVICE(NVIDIA, 0x07f3), board_ahci },            /* MCP73 */
        { PCI_VDEVICE(NVIDIA, 0x07f4), board_ahci },            /* MCP73 */
        { PCI_VDEVICE(NVIDIA, 0x07f5), board_ahci },            /* MCP73 */
        { PCI_VDEVICE(NVIDIA, 0x07f6), board_ahci },            /* MCP73 */
        { PCI_VDEVICE(NVIDIA, 0x07f7), board_ahci },            /* MCP73 */
        { PCI_VDEVICE(NVIDIA, 0x07f8), board_ahci },            /* MCP73 */
        { PCI_VDEVICE(NVIDIA, 0x07f9), board_ahci },            /* MCP73 */
        { PCI_VDEVICE(NVIDIA, 0x07fa), board_ahci },            /* MCP73 */
        { PCI_VDEVICE(NVIDIA, 0x07fb), board_ahci },            /* MCP73 */
        { PCI_VDEVICE(NVIDIA, 0x0ad0), board_ahci },            /* MCP77 */
        { PCI_VDEVICE(NVIDIA, 0x0ad1), board_ahci },            /* MCP77 */
        { PCI_VDEVICE(NVIDIA, 0x0ad2), board_ahci },            /* MCP77 */
        { PCI_VDEVICE(NVIDIA, 0x0ad3), board_ahci },            /* MCP77 */
        { PCI_VDEVICE(NVIDIA, 0x0ad4), board_ahci },            /* MCP77 */
        { PCI_VDEVICE(NVIDIA, 0x0ad5), board_ahci },            /* MCP77 */
        { PCI_VDEVICE(NVIDIA, 0x0ad6), board_ahci },            /* MCP77 */
        { PCI_VDEVICE(NVIDIA, 0x0ad7), board_ahci },            /* MCP77 */
        { PCI_VDEVICE(NVIDIA, 0x0ad8), board_ahci },            /* MCP77 */
        { PCI_VDEVICE(NVIDIA, 0x0ad9), board_ahci },            /* MCP77 */
        { PCI_VDEVICE(NVIDIA, 0x0ada), board_ahci },            /* MCP77 */
        { PCI_VDEVICE(NVIDIA, 0x0adb), board_ahci },            /* MCP77 */
        { PCI_VDEVICE(NVIDIA, 0x0ab4), board_ahci },            /* MCP79 */
        { PCI_VDEVICE(NVIDIA, 0x0ab5), board_ahci },            /* MCP79 */
        { PCI_VDEVICE(NVIDIA, 0x0ab6), board_ahci },            /* MCP79 */
        { PCI_VDEVICE(NVIDIA, 0x0ab7), board_ahci },            /* MCP79 */
        { PCI_VDEVICE(NVIDIA, 0x0ab8), board_ahci },            /* MCP79 */
        { PCI_VDEVICE(NVIDIA, 0x0ab9), board_ahci },            /* MCP79 */
        { PCI_VDEVICE(NVIDIA, 0x0aba), board_ahci },            /* MCP79 */
        { PCI_VDEVICE(NVIDIA, 0x0abb), board_ahci },            /* MCP79 */
        { PCI_VDEVICE(NVIDIA, 0x0abc), board_ahci },            /* MCP79 */
        { PCI_VDEVICE(NVIDIA, 0x0abd), board_ahci },            /* MCP79 */
        { PCI_VDEVICE(NVIDIA, 0x0abe), board_ahci },            /* MCP79 */
        { PCI_VDEVICE(NVIDIA, 0x0abf), board_ahci },            /* MCP79 */
        { PCI_VDEVICE(NVIDIA, 0x0bc8), board_ahci },            /* MCP7B */
        { PCI_VDEVICE(NVIDIA, 0x0bc9), board_ahci },            /* MCP7B */
        { PCI_VDEVICE(NVIDIA, 0x0bca), board_ahci },            /* MCP7B */
        { PCI_VDEVICE(NVIDIA, 0x0bcb), board_ahci },            /* MCP7B */
        { PCI_VDEVICE(NVIDIA, 0x0bcc), board_ahci },            /* MCP7B */
        { PCI_VDEVICE(NVIDIA, 0x0bcd), board_ahci },            /* MCP7B */
        { PCI_VDEVICE(NVIDIA, 0x0bce), board_ahci },            /* MCP7B */
        { PCI_VDEVICE(NVIDIA, 0x0bcf), board_ahci },            /* MCP7B */
        { PCI_VDEVICE(NVIDIA, 0x0bd0), board_ahci },            /* MCP7B */
        { PCI_VDEVICE(NVIDIA, 0x0bd1), board_ahci },            /* MCP7B */
        { PCI_VDEVICE(NVIDIA, 0x0bd2), board_ahci },            /* MCP7B */
        { PCI_VDEVICE(NVIDIA, 0x0bd3), board_ahci },            /* MCP7B */

        /* SiS */
        { PCI_VDEVICE(SI, 0x1184), board_ahci }, /* SiS 966 */
        { PCI_VDEVICE(SI, 0x1185), board_ahci }, /* SiS 966 */
        { PCI_VDEVICE(SI, 0x0186), board_ahci }, /* SiS 968 */

        /* Marvell */
        { PCI_VDEVICE(MARVELL, 0x6145), board_ahci_mv },        /* 6145 */
        { PCI_VDEVICE(MARVELL, 0x6121), board_ahci_mv },        /* 6121 */

        /* Generic, PCI class code for AHCI */
        { PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
          PCI_CLASS_STORAGE_SATA_AHCI, 0xffffff, board_ahci },

        { }     /* terminate list */
};


static struct pci_driver ahci_pci_driver = {
        .name                   = DRV_NAME,
        .id_table               = ahci_pci_tbl,
        .probe                  = ahci_init_one,
        .remove                 = ata_pci_remove_one,
#ifdef CONFIG_PM
        .suspend                = ahci_pci_device_suspend,
        .resume                 = ahci_pci_device_resume,
#endif
};


static inline int ahci_nr_ports(u32 cap)
{
        return (cap & 0x1f) + 1;
}

static inline void __iomem *__ahci_port_base(struct ata_host *host,
                                             unsigned int port_no)
{
        void __iomem *mmio = host->iomap[AHCI_PCI_BAR];

        return mmio + 0x100 + (port_no * 0x80);
}

static inline void __iomem *ahci_port_base(struct ata_port *ap)
{
        return __ahci_port_base(ap->host, ap->port_no);
}

static void ahci_enable_ahci(void __iomem *mmio)
{
        u32 tmp;

        /* turn on AHCI_EN */
        tmp = readl(mmio + HOST_CTL);
        if (!(tmp & HOST_AHCI_EN)) {
                tmp |= HOST_AHCI_EN;
                writel(tmp, mmio + HOST_CTL);
                tmp = readl(mmio + HOST_CTL);   /* flush && sanity check */
                WARN_ON(!(tmp & HOST_AHCI_EN));
        }
}

/**
 *      ahci_save_initial_config - Save and fixup initial config values
 *      @pdev: target PCI device
 *      @hpriv: host private area to store config values
 *
 *      Some registers containing configuration info might be setup by
 *      BIOS and might be cleared on reset.  This function saves the
 *      initial values of those registers into @hpriv such that they
 *      can be restored after controller reset.
 *
 *      If inconsistent, config values are fixed up by this function.
 *
 *      LOCKING:
 *      None.
 */
static void ahci_save_initial_config(struct pci_dev *pdev,
                                     struct ahci_host_priv *hpriv)
{
        void __iomem *mmio = pcim_iomap_table(pdev)[AHCI_PCI_BAR];
        u32 cap, port_map;
        int i;
        int mv;

        /* make sure AHCI mode is enabled before accessing CAP */
        ahci_enable_ahci(mmio);

        /* Values prefixed with saved_ are written back to host after
         * reset.  Values without are used for driver operation.
         */
        hpriv->saved_cap = cap = readl(mmio + HOST_CAP);
        hpriv->saved_port_map = port_map = readl(mmio + HOST_PORTS_IMPL);

        /* some chips have errata preventing 64bit use */
        if ((cap & HOST_CAP_64) && (hpriv->flags & AHCI_HFLAG_32BIT_ONLY)) {
                dev_printk(KERN_INFO, &pdev->dev,
                           "controller can't do 64bit DMA, forcing 32bit\n");
                cap &= ~HOST_CAP_64;
        }

        if ((cap & HOST_CAP_NCQ) && (hpriv->flags & AHCI_HFLAG_NO_NCQ)) {
                dev_printk(KERN_INFO, &pdev->dev,
                           "controller can't do NCQ, turning off CAP_NCQ\n");
                cap &= ~HOST_CAP_NCQ;
        }

        if ((cap & HOST_CAP_PMP) && (hpriv->flags & AHCI_HFLAG_NO_PMP)) {
                dev_printk(KERN_INFO, &pdev->dev,
                           "controller can't do PMP, turning off CAP_PMP\n");
                cap &= ~HOST_CAP_PMP;
        }

        /*
         * Temporary Marvell 6145 hack: PATA port presence
         * is asserted through the standard AHCI port
         * presence register, as bit 4 (counting from 0)
         */
        if (hpriv->flags & AHCI_HFLAG_MV_PATA) {
                if (pdev->device == 0x6121)
                        mv = 0x3;
                else
                        mv = 0xf;
                dev_printk(KERN_ERR, &pdev->dev,
                           "MV_AHCI HACK: port_map %x -> %x\n",
                           port_map,
                           port_map & mv);

                port_map &= mv;
        }

        /* cross check port_map and cap.n_ports */
        if (port_map) {
                int map_ports = 0;

                for (i = 0; i < AHCI_MAX_PORTS; i++)
                        if (port_map & (1 << i))
                                map_ports++;

                /* If PI has more ports than n_ports, whine, clear
                 * port_map and let it be generated from n_ports.
                 */
                if (map_ports > ahci_nr_ports(cap)) {
                        dev_printk(KERN_WARNING, &pdev->dev,
                                   "implemented port map (0x%x) contains more "
                                   "ports than nr_ports (%u), using nr_ports\n",
                                   port_map, ahci_nr_ports(cap));
                        port_map = 0;
                }
        }

        /* fabricate port_map from cap.nr_ports */
        if (!port_map) {
                port_map = (1 << ahci_nr_ports(cap)) - 1;
                dev_printk(KERN_WARNING, &pdev->dev,
                           "forcing PORTS_IMPL to 0x%x\n", port_map);

                /* write the fixed up value to the PI register */
                hpriv->saved_port_map = port_map;
        }

        /* record values to use during operation */
        hpriv->cap = cap;
        hpriv->port_map = port_map;
}

/**
 *      ahci_restore_initial_config - Restore initial config
 *      @host: target ATA host
 *
 *      Restore initial config stored by ahci_save_initial_config().
 *
 *      LOCKING:
 *      None.
 */
static void ahci_restore_initial_config(struct ata_host *host)
{
        struct ahci_host_priv *hpriv = host->private_data;
        void __iomem *mmio = host->iomap[AHCI_PCI_BAR];

        writel(hpriv->saved_cap, mmio + HOST_CAP);
        writel(hpriv->saved_port_map, mmio + HOST_PORTS_IMPL);
        (void) readl(mmio + HOST_PORTS_IMPL);   /* flush */
}

static unsigned ahci_scr_offset(struct ata_port *ap, unsigned int sc_reg)
{
        static const int offset[] = {
                [SCR_STATUS]            = PORT_SCR_STAT,
                [SCR_CONTROL]           = PORT_SCR_CTL,
                [SCR_ERROR]             = PORT_SCR_ERR,
                [SCR_ACTIVE]            = PORT_SCR_ACT,
                [SCR_NOTIFICATION]      = PORT_SCR_NTF,
        };
        struct ahci_host_priv *hpriv = ap->host->private_data;

        if (sc_reg < ARRAY_SIZE(offset) &&
            (sc_reg != SCR_NOTIFICATION || (hpriv->cap & HOST_CAP_SNTF)))
                return offset[sc_reg];
        return 0;
}

static int ahci_scr_read(struct ata_port *ap, unsigned int sc_reg, u32 *val)
{
        void __iomem *port_mmio = ahci_port_base(ap);
        int offset = ahci_scr_offset(ap, sc_reg);

        if (offset) {
                *val = readl(port_mmio + offset);
                return 0;
        }
        return -EINVAL;
}

static int ahci_scr_write(struct ata_port *ap, unsigned int sc_reg, u32 val)
{
        void __iomem *port_mmio = ahci_port_base(ap);
        int offset = ahci_scr_offset(ap, sc_reg);

        if (offset) {
                writel(val, port_mmio + offset);
                return 0;
        }
        return -EINVAL;
}

static void ahci_start_engine(struct ata_port *ap)
{
        void __iomem *port_mmio = ahci_port_base(ap);
        u32 tmp;

        /* start DMA */
        tmp = readl(port_mmio + PORT_CMD);
        tmp |= PORT_CMD_START;
        writel(tmp, port_mmio + PORT_CMD);
        readl(port_mmio + PORT_CMD); /* flush */
}

static int ahci_stop_engine(struct ata_port *ap)
{
        void __iomem *port_mmio = ahci_port_base(ap);
        u32 tmp;

        tmp = readl(port_mmio + PORT_CMD);

        /* check if the HBA is idle */
        if ((tmp & (PORT_CMD_START | PORT_CMD_LIST_ON)) == 0)
                return 0;

        /* setting HBA to idle */
        tmp &= ~PORT_CMD_START;
        writel(tmp, port_mmio + PORT_CMD);

        /* wait for engine to stop. This could be as long as 500 msec */
        tmp = ata_wait_register(port_mmio + PORT_CMD,
                                PORT_CMD_LIST_ON, PORT_CMD_LIST_ON, 1, 500);
        if (tmp & PORT_CMD_LIST_ON)
                return -EIO;

        return 0;
}

static void ahci_start_fis_rx(struct ata_port *ap)
{
        void __iomem *port_mmio = ahci_port_base(ap);
        struct ahci_host_priv *hpriv = ap->host->private_data;
        struct ahci_port_priv *pp = ap->private_data;
        u32 tmp;

        /* set FIS registers */
        if (hpriv->cap & HOST_CAP_64)
                writel((pp->cmd_slot_dma >> 16) >> 16,
                       port_mmio + PORT_LST_ADDR_HI);
        writel(pp->cmd_slot_dma & 0xffffffff, port_mmio + PORT_LST_ADDR);

        if (hpriv->cap & HOST_CAP_64)
                writel((pp->rx_fis_dma >> 16) >> 16,
                       port_mmio + PORT_FIS_ADDR_HI);
        writel(pp->rx_fis_dma & 0xffffffff, port_mmio + PORT_FIS_ADDR);

        /* enable FIS reception */
        tmp = readl(port_mmio + PORT_CMD);
        tmp |= PORT_CMD_FIS_RX;
        writel(tmp, port_mmio + PORT_CMD);

        /* flush */
        readl(port_mmio + PORT_CMD);
}

static int ahci_stop_fis_rx(struct ata_port *ap)
{
        void __iomem *port_mmio = ahci_port_base(ap);
        u32 tmp;

        /* disable FIS reception */
        tmp = readl(port_mmio + PORT_CMD);
        tmp &= ~PORT_CMD_FIS_RX;
        writel(tmp, port_mmio + PORT_CMD);

        /* wait for completion, spec says 500ms, give it 1000 */
        tmp = ata_wait_register(port_mmio + PORT_CMD, PORT_CMD_FIS_ON,
                                PORT_CMD_FIS_ON, 10, 1000);
        if (tmp & PORT_CMD_FIS_ON)
                return -EBUSY;

        return 0;
}

static void ahci_power_up(struct ata_port *ap)
{
        struct ahci_host_priv *hpriv = ap->host->private_data;
        void __iomem *port_mmio = ahci_port_base(ap);
        u32 cmd;

        cmd = readl(port_mmio + PORT_CMD) & ~PORT_CMD_ICC_MASK;

        /* spin up device */
        if (hpriv->cap & HOST_CAP_SSS) {
                cmd |= PORT_CMD_SPIN_UP;
                writel(cmd, port_mmio + PORT_CMD);
        }

        /* wake up link */
        writel(cmd | PORT_CMD_ICC_ACTIVE, port_mmio + PORT_CMD);
}

static void ahci_disable_alpm(struct ata_port *ap)
{
        struct ahci_host_priv *hpriv = ap->host->private_data;
        void __iomem *port_mmio = ahci_port_base(ap);
        u32 cmd;
        struct ahci_port_priv *pp = ap->private_data;

        /* IPM bits should be disabled by libata-core */
        /* get the existing command bits */
        cmd = readl(port_mmio + PORT_CMD);

        /* disable ALPM and ASP */
        cmd &= ~PORT_CMD_ASP;
        cmd &= ~PORT_CMD_ALPE;

        /* force the interface back to active */
        cmd |= PORT_CMD_ICC_ACTIVE;

        /* write out new cmd value */
        writel(cmd, port_mmio + PORT_CMD);
        cmd = readl(port_mmio + PORT_CMD);

        /* wait 10ms to be sure we've come out of any low power state */
        msleep(10);

        /* clear out any PhyRdy stuff from interrupt status */
        writel(PORT_IRQ_PHYRDY, port_mmio + PORT_IRQ_STAT);

        /* go ahead and clean out PhyRdy Change from Serror too */
        ahci_scr_write(ap, SCR_ERROR, ((1 << 16) | (1 << 18)));

        /*
         * Clear flag to indicate that we should ignore all PhyRdy
         * state changes
         */
        hpriv->flags &= ~AHCI_HFLAG_NO_HOTPLUG;

        /*
         * Enable interrupts on Phy Ready.
         */
        pp->intr_mask |= PORT_IRQ_PHYRDY;
        writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);

        /*
         * don't change the link pm policy - we can be called
         * just to turn of link pm temporarily
         */
}

static int ahci_enable_alpm(struct ata_port *ap,
        enum link_pm policy)
{
        struct ahci_host_priv *hpriv = ap->host->private_data;
        void __iomem *port_mmio = ahci_port_base(ap);
        u32 cmd;
        struct ahci_port_priv *pp = ap->private_data;
        u32 asp;

        /* Make sure the host is capable of link power management */
        if (!(hpriv->cap & HOST_CAP_ALPM))
                return -EINVAL;

        switch (policy) {
        case MAX_PERFORMANCE:
        case NOT_AVAILABLE:
                /*
                 * if we came here with NOT_AVAILABLE,
                 * it just means this is the first time we
                 * have tried to enable - default to max performance,
                 * and let the user go to lower power modes on request.
                 */
                ahci_disable_alpm(ap);
                return 0;
        case MIN_POWER:
                /* configure HBA to enter SLUMBER */
                asp = PORT_CMD_ASP;
                break;
        case MEDIUM_POWER:
                /* configure HBA to enter PARTIAL */
                asp = 0;
                break;
        default:
                return -EINVAL;
        }

        /*
         * Disable interrupts on Phy Ready. This keeps us from
         * getting woken up due to spurious phy ready interrupts
         * TBD - Hot plug should be done via polling now, is
         * that even supported?
         */
        pp->intr_mask &= ~PORT_IRQ_PHYRDY;
        writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);

        /*
         * Set a flag to indicate that we should ignore all PhyRdy
         * state changes since these can happen now whenever we
         * change link state
         */
        hpriv->flags |= AHCI_HFLAG_NO_HOTPLUG;

        /* get the existing command bits */
        cmd = readl(port_mmio + PORT_CMD);

        /*
         * Set ASP based on Policy
         */
        cmd |= asp;

        /*
         * Setting this bit will instruct the HBA to aggressively
         * enter a lower power link state when it's appropriate and
         * based on the value set above for ASP
         */
        cmd |= PORT_CMD_ALPE;

        /* write out new cmd value */
        writel(cmd, port_mmio + PORT_CMD);
        cmd = readl(port_mmio + PORT_CMD);

        /* IPM bits should be set by libata-core */
        return 0;
}

#ifdef CONFIG_PM
static void ahci_power_down(struct ata_port *ap)
{
        struct ahci_host_priv *hpriv = ap->host->private_data;
        void __iomem *port_mmio = ahci_port_base(ap);
        u32 cmd, scontrol;

        if (!(hpriv->cap & HOST_CAP_SSS))
                return;

        /* put device into listen mode, first set PxSCTL.DET to 0 */
        scontrol = readl(port_mmio + PORT_SCR_CTL);
        scontrol &= ~0xf;
        writel(scontrol, port_mmio + PORT_SCR_CTL);

        /* then set PxCMD.SUD to 0 */
        cmd = readl(port_mmio + PORT_CMD) & ~PORT_CMD_ICC_MASK;
        cmd &= ~PORT_CMD_SPIN_UP;
        writel(cmd, port_mmio + PORT_CMD);
}
#endif

static void ahci_start_port(struct ata_port *ap)
{
        /* enable FIS reception */
        ahci_start_fis_rx(ap);

        /* enable DMA */
        ahci_start_engine(ap);
}

static int ahci_deinit_port(struct ata_port *ap, const char **emsg)
{
        int rc;

        /* disable DMA */
        rc = ahci_stop_engine(ap);
        if (rc) {
                *emsg = "failed to stop engine";
                return rc;
        }

        /* disable FIS reception */
        rc = ahci_stop_fis_rx(ap);
        if (rc) {
                *emsg = "failed stop FIS RX";
                return rc;
        }

        return 0;
}

static int ahci_reset_controller(struct ata_host *host)
{
        struct pci_dev *pdev = to_pci_dev(host->dev);
        struct ahci_host_priv *hpriv = host->private_data;
        void __iomem *mmio = host->iomap[AHCI_PCI_BAR];
        u32 tmp;

        /* we must be in AHCI mode, before using anything
         * AHCI-specific, such as HOST_RESET.
         */
        ahci_enable_ahci(mmio);

        /* global controller reset */
        if (!ahci_skip_host_reset) {
                tmp = readl(mmio + HOST_CTL);
                if ((tmp & HOST_RESET) == 0) {
                        writel(tmp | HOST_RESET, mmio + HOST_CTL);
                        readl(mmio + HOST_CTL); /* flush */
                }

                /* reset must complete within 1 second, or
                 * the hardware should be considered fried.
                 */
                ssleep(1);

                tmp = readl(mmio + HOST_CTL);
                if (tmp & HOST_RESET) {
                        dev_printk(KERN_ERR, host->dev,
                                   "controller reset failed (0x%x)\n", tmp);
                        return -EIO;
                }

                /* turn on AHCI mode */
                ahci_enable_ahci(mmio);

                /* Some registers might be cleared on reset.  Restore
                 * initial values.
                 */
                ahci_restore_initial_config(host);
        } else
                dev_printk(KERN_INFO, host->dev,
                           "skipping global host reset\n");

        if (pdev->vendor == PCI_VENDOR_ID_INTEL) {
                u16 tmp16;

                /* configure PCS */
                pci_read_config_word(pdev, 0x92, &tmp16);
                if ((tmp16 & hpriv->port_map) != hpriv->port_map) {
                        tmp16 |= hpriv->port_map;
                        pci_write_config_word(pdev, 0x92, tmp16);
                }
        }

        return 0;
}

static void ahci_port_init(struct pci_dev *pdev, struct ata_port *ap,
                           int port_no, void __iomem *mmio,
                           void __iomem *port_mmio)
{
        const char *emsg = NULL;
        int rc;
        u32 tmp;

        /* make sure port is not active */
        rc = ahci_deinit_port(ap, &emsg);
        if (rc)
                dev_printk(KERN_WARNING, &pdev->dev,
                           "%s (%d)\n", emsg, rc);

        /* clear SError */
        tmp = readl(port_mmio + PORT_SCR_ERR);
        VPRINTK("PORT_SCR_ERR 0x%x\n", tmp);
        writel(tmp, port_mmio + PORT_SCR_ERR);

        /* clear port IRQ */
        tmp = readl(port_mmio + PORT_IRQ_STAT);
        VPRINTK("PORT_IRQ_STAT 0x%x\n", tmp);
        if (tmp)
                writel(tmp, port_mmio + PORT_IRQ_STAT);

        writel(1 << port_no, mmio + HOST_IRQ_STAT);
}

static void ahci_init_controller(struct ata_host *host)
{
        struct ahci_host_priv *hpriv = host->private_data;
        struct pci_dev *pdev = to_pci_dev(host->dev);
        void __iomem *mmio = host->iomap[AHCI_PCI_BAR];
        int i;
        void __iomem *port_mmio;
        u32 tmp;
        int mv;

        if (hpriv->flags & AHCI_HFLAG_MV_PATA) {
                if (pdev->device == 0x6121)
                        mv = 2;
                else
                        mv = 4;
                port_mmio = __ahci_port_base(host, mv);

                writel(0, port_mmio + PORT_IRQ_MASK);

                /* clear port IRQ */
                tmp = readl(port_mmio + PORT_IRQ_STAT);
                VPRINTK("PORT_IRQ_STAT 0x%x\n", tmp);
                if (tmp)
                        writel(tmp, port_mmio + PORT_IRQ_STAT);
        }

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

                port_mmio = ahci_port_base(ap);
                if (ata_port_is_dummy(ap))
                        continue;

                ahci_port_init(pdev, ap, i, mmio, port_mmio);
        }

        tmp = readl(mmio + HOST_CTL);
        VPRINTK("HOST_CTL 0x%x\n", tmp);
        writel(tmp | HOST_IRQ_EN, mmio + HOST_CTL);
        tmp = readl(mmio + HOST_CTL);
        VPRINTK("HOST_CTL 0x%x\n", tmp);
}

static void ahci_dev_config(struct ata_device *dev)
{
        struct ahci_host_priv *hpriv = dev->link->ap->host->private_data;

        if (hpriv->flags & AHCI_HFLAG_SECT255) {
                dev->max_sectors = 255;
                ata_dev_printk(dev, KERN_INFO,
                               "SB600 AHCI: limiting to 255 sectors per cmd\n");
        }
}

static unsigned int ahci_dev_classify(struct ata_port *ap)
{
        void __iomem *port_mmio = ahci_port_base(ap);
        struct ata_taskfile tf;
        u32 tmp;

        tmp = readl(port_mmio + PORT_SIG);
        tf.lbah         = (tmp >> 24)   & 0xff;
        tf.lbam         = (tmp >> 16)   & 0xff;
        tf.lbal         = (tmp >> 8)    & 0xff;
        tf.nsect        = (tmp)         & 0xff;

        return ata_dev_classify(&tf);
}

static void ahci_fill_cmd_slot(struct ahci_port_priv *pp, unsigned int tag,
                               u32 opts)
{
        dma_addr_t cmd_tbl_dma;

        cmd_tbl_dma = pp->cmd_tbl_dma + tag * AHCI_CMD_TBL_SZ;

        pp->cmd_slot[tag].opts = cpu_to_le32(opts);
        pp->cmd_slot[tag].status = 0;
        pp->cmd_slot[tag].tbl_addr = cpu_to_le32(cmd_tbl_dma & 0xffffffff);
        pp->cmd_slot[tag].tbl_addr_hi = cpu_to_le32((cmd_tbl_dma >> 16) >> 16);
}

static int ahci_kick_engine(struct ata_port *ap, int force_restart)
{
        void __iomem *port_mmio = ahci_port_base(ap);
        struct ahci_host_priv *hpriv = ap->host->private_data;
        u8 status = readl(port_mmio + PORT_TFDATA) & 0xFF;
        u32 tmp;
        int busy, rc;

        /* do we need to kick the port? */
        busy = status & (ATA_BUSY | ATA_DRQ);
        if (!busy && !force_restart)
                return 0;

        /* stop engine */
        rc = ahci_stop_engine(ap);
        if (rc)
                goto out_restart;

        /* need to do CLO? */
        if (!busy) {
                rc = 0;
                goto out_restart;
        }

        if (!(hpriv->cap & HOST_CAP_CLO)) {
                rc = -EOPNOTSUPP;
                goto out_restart;
        }

        /* perform CLO */
        tmp = readl(port_mmio + PORT_CMD);
        tmp |= PORT_CMD_CLO;
        writel(tmp, port_mmio + PORT_CMD);

        rc = 0;
        tmp = ata_wait_register(port_mmio + PORT_CMD,
                                PORT_CMD_CLO, PORT_CMD_CLO, 1, 500);
        if (tmp & PORT_CMD_CLO)
                rc = -EIO;

        /* restart engine */
 out_restart:
        ahci_start_engine(ap);
        return rc;
}

static int ahci_exec_polled_cmd(struct ata_port *ap, int pmp,
                                struct ata_taskfile *tf, int is_cmd, u16 flags,
                                unsigned long timeout_msec)
{
        const u32 cmd_fis_len = 5; /* five dwords */
        struct ahci_port_priv *pp = ap->private_data;
        void __iomem *port_mmio = ahci_port_base(ap);
        u8 *fis = pp->cmd_tbl;
        u32 tmp;

        /* prep the command */
        ata_tf_to_fis(tf, pmp, is_cmd, fis);
        ahci_fill_cmd_slot(pp, 0, cmd_fis_len | flags | (pmp << 12));

        /* issue & wait */
        writel(1, port_mmio + PORT_CMD_ISSUE);

        if (timeout_msec) {
                tmp = ata_wait_register(port_mmio + PORT_CMD_ISSUE, 0x1, 0x1,
                                        1, timeout_msec);
                if (tmp & 0x1) {
                        ahci_kick_engine(ap, 1);
                        return -EBUSY;
                }
        } else
                readl(port_mmio + PORT_CMD_ISSUE);      /* flush */

        return 0;
}

static int ahci_check_ready(struct ata_link *link)
{
        void __iomem *port_mmio = ahci_port_base(link->ap);
        u8 status = readl(port_mmio + PORT_TFDATA) & 0xFF;

        if (!(status & ATA_BUSY))
                return 1;
        return 0;
}

static int ahci_softreset(struct ata_link *link, unsigned int *class,
                          unsigned long deadline)
{
        struct ata_port *ap = link->ap;
        int pmp = sata_srst_pmp(link);
        const char *reason = NULL;
        unsigned long now, msecs;
        struct ata_taskfile tf;
        int rc;

        DPRINTK("ENTER\n");

        if (ata_link_offline(link)) {
                DPRINTK("PHY reports no device\n");
                *class = ATA_DEV_NONE;
                return 0;
        }

        /* prepare for SRST (AHCI-1.1 10.4.1) */
        rc = ahci_kick_engine(ap, 1);
        if (rc && rc != -EOPNOTSUPP)
                ata_link_printk(link, KERN_WARNING,
                                "failed to reset engine (errno=%d)\n", rc);

        ata_tf_init(link->device, &tf);

        /* issue the first D2H Register FIS */
        msecs = 0;
        now = jiffies;
        if (time_after(now, deadline))
                msecs = jiffies_to_msecs(deadline - now);

        tf.ctl |= ATA_SRST;
        if (ahci_exec_polled_cmd(ap, pmp, &tf, 0,
                                 AHCI_CMD_RESET | AHCI_CMD_CLR_BUSY, msecs)) {
                rc = -EIO;
                reason = "1st FIS failed";
                goto fail;
        }

        /* spec says at least 5us, but be generous and sleep for 1ms */
        msleep(1);

        /* issue the second D2H Register FIS */
        tf.ctl &= ~ATA_SRST;
        ahci_exec_polled_cmd(ap, pmp, &tf, 0, 0, 0);

        /* wait for link to become ready */
        rc = ata_wait_after_reset(link, deadline, ahci_check_ready);
        /* link occupied, -ENODEV too is an error */
        if (rc) {
                reason = "device not ready";
                goto fail;
        }
        *class = ahci_dev_classify(ap);

        DPRINTK("EXIT, class=%u\n", *class);
        return 0;

 fail:
        ata_link_printk(link, KERN_ERR, "softreset failed (%s)\n", reason);
        return rc;
}

static int ahci_hardreset(struct ata_link *link, unsigned int *class,
                          unsigned long deadline)
{
        const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
        struct ata_port *ap = link->ap;
        struct ahci_port_priv *pp = ap->private_data;
        u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
        struct ata_taskfile tf;
        bool online;
        int rc;

        DPRINTK("ENTER\n");

        ahci_stop_engine(ap);

        /* clear D2H reception area to properly wait for D2H FIS */
        ata_tf_init(link->device, &tf);
        tf.command = 0x80;
        ata_tf_to_fis(&tf, 0, 0, d2h_fis);

        rc = sata_link_hardreset(link, timing, deadline, &online,
                                 ahci_check_ready);

        ahci_start_engine(ap);

        if (online)
                *class = ahci_dev_classify(ap);

        DPRINTK("EXIT, rc=%d, class=%u\n", rc, *class);
        return rc;
}

static int ahci_vt8251_hardreset(struct ata_link *link, unsigned int *class,
                                 unsigned long deadline)
{
        struct ata_port *ap = link->ap;
        bool online;
        int rc;

        DPRINTK("ENTER\n");

        ahci_stop_engine(ap);

        rc = sata_link_hardreset(link, sata_ehc_deb_timing(&link->eh_context),
                                 deadline, &online, NULL);

        ahci_start_engine(ap);

        DPRINTK("EXIT, rc=%d, class=%u\n", rc, *class);

        /* vt8251 doesn't clear BSY on signature FIS reception,
         * request follow-up softreset.
         */
        return online ? -EAGAIN : rc;
}

static int ahci_p5wdh_hardreset(struct ata_link *link, unsigned int *class,
                                unsigned long deadline)
{
        struct ata_port *ap = link->ap;
        struct ahci_port_priv *pp = ap->private_data;
        u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
        struct ata_taskfile tf;
        bool online;
        int rc;

        ahci_stop_engine(ap);

        /* clear D2H reception area to properly wait for D2H FIS */
        ata_tf_init(link->device, &tf);
        tf.command = 0x80;
        ata_tf_to_fis(&tf, 0, 0, d2h_fis);

        rc = sata_link_hardreset(link, sata_ehc_deb_timing(&link->eh_context),
                                 deadline, &online, NULL);

        ahci_start_engine(ap);

        /* The pseudo configuration device on SIMG4726 attached to
         * ASUS P5W-DH Deluxe doesn't send signature FIS after
         * hardreset if no device is attached to the first downstream
         * port && the pseudo device locks up on SRST w/ PMP==0.  To
         * work around this, wait for !BSY only briefly.  If BSY isn't
         * cleared, perform CLO and proceed to IDENTIFY (achieved by
         * ATA_LFLAG_NO_SRST and ATA_LFLAG_ASSUME_ATA).
         *
         * Wait for two seconds.  Devices attached to downstream port
         * which can't process the following IDENTIFY after this will
         * have to be reset again.  For most cases, this should
         * suffice while making probing snappish enough.
         */
        if (online) {
                rc = ata_wait_after_reset(link, jiffies + 2 * HZ,
                                          ahci_check_ready);
                if (rc)
                        ahci_kick_engine(ap, 0);
        }
        return rc;
}

static void ahci_postreset(struct ata_link *link, unsigned int *class)
{
        struct ata_port *ap = link->ap;
        void __iomem *port_mmio = ahci_port_base(ap);
        u32 new_tmp, tmp;

        ata_std_postreset(link, class);

        /* Make sure port's ATAPI bit is set appropriately */
        new_tmp = tmp = readl(port_mmio + PORT_CMD);
        if (*class == ATA_DEV_ATAPI)
                new_tmp |= PORT_CMD_ATAPI;
        else
                new_tmp &= ~PORT_CMD_ATAPI;
        if (new_tmp != tmp) {
                writel(new_tmp, port_mmio + PORT_CMD);
                readl(port_mmio + PORT_CMD); /* flush */
        }
}

static unsigned int ahci_fill_sg(struct ata_queued_cmd *qc, void *cmd_tbl)
{
        struct scatterlist *sg;
        struct ahci_sg *ahci_sg = cmd_tbl + AHCI_CMD_TBL_HDR_SZ;
        unsigned int si;

        VPRINTK("ENTER\n");

        /*
         * Next, the S/G list.
         */
        for_each_sg(qc->sg, sg, qc->n_elem, si) {
                dma_addr_t addr = sg_dma_address(sg);
                u32 sg_len = sg_dma_len(sg);

                ahci_sg[si].addr = cpu_to_le32(addr & 0xffffffff);
                ahci_sg[si].addr_hi = cpu_to_le32((addr >> 16) >> 16);
                ahci_sg[si].flags_size = cpu_to_le32(sg_len - 1);
        }

        return si;
}

static void ahci_qc_prep(struct ata_queued_cmd *qc)
{
        struct ata_port *ap = qc->ap;
        struct ahci_port_priv *pp = ap->private_data;
        int is_atapi = ata_is_atapi(qc->tf.protocol);
        void *cmd_tbl;
        u32 opts;
        const u32 cmd_fis_len = 5; /* five dwords */
        unsigned int n_elem;

        /*
         * Fill in command table information.  First, the header,
         * a SATA Register - Host to Device command FIS.
         */
        cmd_tbl = pp->cmd_tbl + qc->tag * AHCI_CMD_TBL_SZ;

        ata_tf_to_fis(&qc->tf, qc->dev->link->pmp, 1, cmd_tbl);
        if (is_atapi) {
                memset(cmd_tbl + AHCI_CMD_TBL_CDB, 0, 32);
                memcpy(cmd_tbl + AHCI_CMD_TBL_CDB, qc->cdb, qc->dev->cdb_len);
        }

        n_elem = 0;
        if (qc->flags & ATA_QCFLAG_DMAMAP)
                n_elem = ahci_fill_sg(qc, cmd_tbl);

        /*
         * Fill in command slot information.
         */
        opts = cmd_fis_len | n_elem << 16 | (qc->dev->link->pmp << 12);
        if (qc->tf.flags & ATA_TFLAG_WRITE)
                opts |= AHCI_CMD_WRITE;
        if (is_atapi)
                opts |= AHCI_CMD_ATAPI | AHCI_CMD_PREFETCH;

        ahci_fill_cmd_slot(pp, qc->tag, opts);
}

static void ahci_error_intr(struct ata_port *ap, u32 irq_stat)
{
        struct ahci_host_priv *hpriv = ap->host->private_data;
        struct ahci_port_priv *pp = ap->private_data;
        struct ata_eh_info *host_ehi = &ap->link.eh_info;
        struct ata_link *link = NULL;
        struct ata_queued_cmd *active_qc;
        struct ata_eh_info *active_ehi;
        u32 serror;

        /* determine active link */
        ata_port_for_each_link(link, ap)
                if (ata_link_active(link))
                        break;
        if (!link)
                link = &ap->link;

        active_qc = ata_qc_from_tag(ap, link->active_tag);
        active_ehi = &link->eh_info;

        /* record irq stat */
        ata_ehi_clear_desc(host_ehi);
        ata_ehi_push_desc(host_ehi, "irq_stat 0x%08x", irq_stat);

        /* AHCI needs SError cleared; otherwise, it might lock up */
        ahci_scr_read(ap, SCR_ERROR, &serror);
        ahci_scr_write(ap, SCR_ERROR, serror);
        host_ehi->serror |= serror;

        /* some controllers set IRQ_IF_ERR on device errors, ignore it */
        if (hpriv->flags & AHCI_HFLAG_IGN_IRQ_IF_ERR)
                irq_stat &= ~PORT_IRQ_IF_ERR;

        if (irq_stat & PORT_IRQ_TF_ERR) {
                /* If qc is active, charge it; otherwise, the active
                 * link.  There's no active qc on NCQ errors.  It will
                 * be determined by EH by reading log page 10h.
                 */
                if (active_qc)
                        active_qc->err_mask |= AC_ERR_DEV;
                else
                        active_ehi->err_mask |= AC_ERR_DEV;

                if (hpriv->flags & AHCI_HFLAG_IGN_SERR_INTERNAL)
                        host_ehi->serror &= ~SERR_INTERNAL;
        }

        if (irq_stat & PORT_IRQ_UNK_FIS) {
                u32 *unk = (u32 *)(pp->rx_fis + RX_FIS_UNK);

                active_ehi->err_mask |= AC_ERR_HSM;
                active_ehi->action |= ATA_EH_RESET;
                ata_ehi_push_desc(active_ehi,
                                  "unknown FIS %08x %08x %08x %08x" ,
                                  unk[0], unk[1], unk[2], unk[3]);
        }

        if (sata_pmp_attached(ap) && (irq_stat & PORT_IRQ_BAD_PMP)) {
                active_ehi->err_mask |= AC_ERR_HSM;
                active_ehi->action |= ATA_EH_RESET;
                ata_ehi_push_desc(active_ehi, "incorrect PMP");
        }

        if (irq_stat & (PORT_IRQ_HBUS_ERR | PORT_IRQ_HBUS_DATA_ERR)) {
                host_ehi->err_mask |= AC_ERR_HOST_BUS;
                host_ehi->action |= ATA_EH_RESET;
                ata_ehi_push_desc(host_ehi, "host bus error");
        }

        if (irq_stat & PORT_IRQ_IF_ERR) {
                host_ehi->err_mask |= AC_ERR_ATA_BUS;
                host_ehi->action |= ATA_EH_RESET;
                ata_ehi_push_desc(host_ehi, "interface fatal error");
        }

        if (irq_stat & (PORT_IRQ_CONNECT | PORT_IRQ_PHYRDY)) {
                ata_ehi_hotplugged(host_ehi);
                ata_ehi_push_desc(host_ehi, "%s",
                        irq_stat & PORT_IRQ_CONNECT ?
                        "connection status changed" : "PHY RDY changed");
        }

        /* okay, let's hand over to EH */

        if (irq_stat & PORT_IRQ_FREEZE)
                ata_port_freeze(ap);
        else
                ata_port_abort(ap);
}

static void ahci_port_intr(struct ata_port *ap)
{
        void __iomem *port_mmio = ahci_port_base(ap);
        struct ata_eh_info *ehi = &ap->link.eh_info;
        struct ahci_port_priv *pp = ap->private_data;
        struct ahci_host_priv *hpriv = ap->host->private_data;
        int resetting = !!(ap->pflags & ATA_PFLAG_RESETTING);
        u32 status, qc_active;
        int rc;

        status = readl(port_mmio + PORT_IRQ_STAT);
        writel(status, port_mmio + PORT_IRQ_STAT);

        /* ignore BAD_PMP while resetting */
        if (unlikely(resetting))
                status &= ~PORT_IRQ_BAD_PMP;

        /* If we are getting PhyRdy, this is
         * just a power state change, we should
         * clear out this, plus the PhyRdy/Comm
         * Wake bits from Serror
         */
        if ((hpriv->flags & AHCI_HFLAG_NO_HOTPLUG) &&
                (status & PORT_IRQ_PHYRDY)) {
                status &= ~PORT_IRQ_PHYRDY;
                ahci_scr_write(ap, SCR_ERROR, ((1 << 16) | (1 << 18)));
        }

        if (unlikely(status & PORT_IRQ_ERROR)) {
                ahci_error_intr(ap, status);
                return;
        }

        if (status & PORT_IRQ_SDB_FIS) {
                /* If SNotification is available, leave notification
                 * handling to sata_async_notification().  If not,
                 * emulate it by snooping SDB FIS RX area.
                 *
                 * Snooping FIS RX area is probably cheaper than
                 * poking SNotification but some constrollers which
                 * implement SNotification, ICH9 for example, don't
                 * store AN SDB FIS into receive area.
                 */
                if (hpriv->cap & HOST_CAP_SNTF)
                        sata_async_notification(ap);
                else {
                        /* If the 'N' bit in word 0 of the FIS is set,
                         * we just received asynchronous notification.
                         * Tell libata about it.
                         */
                        const __le32 *f = pp->rx_fis + RX_FIS_SDB;
                        u32 f0 = le32_to_cpu(f[0]);

                        if (f0 & (1 << 15))
                                sata_async_notification(ap);
                }
        }

        /* pp->active_link is valid iff any command is in flight */
        if (ap->qc_active && pp->active_link->sactive)
                qc_active = readl(port_mmio + PORT_SCR_ACT);
        else
                qc_active = readl(port_mmio + PORT_CMD_ISSUE);

        rc = ata_qc_complete_multiple(ap, qc_active);

        /* while resetting, invalid completions are expected */
        if (unlikely(rc < 0 && !resetting)) {
                ehi->err_mask |= AC_ERR_HSM;
                ehi->action |= ATA_EH_RESET;
                ata_port_freeze(ap);
        }
}

static irqreturn_t ahci_interrupt(int irq, void *dev_instance)
{
        struct ata_host *host = dev_instance;
        struct ahci_host_priv *hpriv;
        unsigned int i, handled = 0;
        void __iomem *mmio;
        u32 irq_stat, irq_ack = 0;

        VPRINTK("ENTER\n");

        hpriv = host->private_data;
        mmio = host->iomap[AHCI_PCI_BAR];

        /* sigh.  0xffffffff is a valid return from h/w */
        irq_stat = readl(mmio + HOST_IRQ_STAT);
        irq_stat &= hpriv->port_map;
        if (!irq_stat)
                return IRQ_NONE;

        spin_lock(&host->lock);

        for (i = 0; i < host->n_ports; i++) {
                struct ata_port *ap;

                if (!(irq_stat & (1 << i)))
                        continue;

                ap = host->ports[i];
                if (ap) {
                        ahci_port_intr(ap);
                        VPRINTK("port %u\n", i);
                } else {
                        VPRINTK("port %u (no irq)\n", i);
                        if (ata_ratelimit())
                                dev_printk(KERN_WARNING, host->dev,
                                        "interrupt on disabled port %u\n", i);
                }

                irq_ack |= (1 << i);
        }

        if (irq_ack) {
                writel(irq_ack, mmio + HOST_IRQ_STAT);
                handled = 1;
        }

        spin_unlock(&host->lock);

        VPRINTK("EXIT\n");

        return IRQ_RETVAL(handled);
}

static unsigned int ahci_qc_issue(struct ata_queued_cmd *qc)
{
        struct ata_port *ap = qc->ap;
        void __iomem *port_mmio = ahci_port_base(ap);
        struct ahci_port_priv *pp = ap->private_data;

        /* Keep track of the currently active link.  It will be used
         * in completion path to determine whether NCQ phase is in
         * progress.
         */
        pp->active_link = qc->dev->link;

        if (qc->tf.protocol == ATA_PROT_NCQ)
                writel(1 << qc->tag, port_mmio + PORT_SCR_ACT);
        writel(1 << qc->tag, port_mmio + PORT_CMD_ISSUE);
        readl(port_mmio + PORT_CMD_ISSUE);      /* flush */

        return 0;
}

static bool ahci_qc_fill_rtf(struct ata_queued_cmd *qc)
{
        struct ahci_port_priv *pp = qc->ap->private_data;
        u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;

        ata_tf_from_fis(d2h_fis, &qc->result_tf);
        return true;
}

static void ahci_freeze(struct ata_port *ap)
{
        void __iomem *port_mmio = ahci_port_base(ap);

        /* turn IRQ off */
        writel(0, port_mmio + PORT_IRQ_MASK);
}

static void ahci_thaw(struct ata_port *ap)
{
        void __iomem *mmio = ap->host->iomap[AHCI_PCI_BAR];
        void __iomem *port_mmio = ahci_port_base(ap);
        u32 tmp;
        struct ahci_port_priv *pp = ap->private_data;

        /* clear IRQ */
        tmp = readl(port_mmio + PORT_IRQ_STAT);
        writel(tmp, port_mmio + PORT_IRQ_STAT);
        writel(1 << ap->port_no, mmio + HOST_IRQ_STAT);

        /* turn IRQ back on */
        writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
}

static void ahci_error_handler(struct ata_port *ap)
{
        if (!(ap->pflags & ATA_PFLAG_FROZEN)) {
                /* restart engine */
                ahci_stop_engine(ap);
                ahci_start_engine(ap);
        }

        sata_pmp_error_handler(ap);
}

static void ahci_post_internal_cmd(struct ata_queued_cmd *qc)
{
        struct ata_port *ap = qc->ap;

        /* make DMA engine forget about the failed command */
        if (qc->flags & ATA_QCFLAG_FAILED)
                ahci_kick_engine(ap, 1);
}

static void ahci_pmp_attach(struct ata_port *ap)
{
        void __iomem *port_mmio = ahci_port_base(ap);
        struct ahci_port_priv *pp = ap->private_data;
        u32 cmd;

        cmd = readl(port_mmio + PORT_CMD);
        cmd |= PORT_CMD_PMP;
        writel(cmd, port_mmio + PORT_CMD);

        pp->intr_mask |= PORT_IRQ_BAD_PMP;
        writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
}

static void ahci_pmp_detach(struct ata_port *ap)
{
        void __iomem *port_mmio = ahci_port_base(ap);
        struct ahci_port_priv *pp = ap->private_data;
        u32 cmd;

        cmd = readl(port_mmio + PORT_CMD);
        cmd &= ~PORT_CMD_PMP;
        writel(cmd, port_mmio + PORT_CMD);

        pp->intr_mask &= ~PORT_IRQ_BAD_PMP;
        writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
}

static int ahci_port_resume(struct ata_port *ap)
{
        ahci_power_up(ap);
        ahci_start_port(ap);

        if (sata_pmp_attached(ap))
                ahci_pmp_attach(ap);
        else
                ahci_pmp_detach(ap);

        return 0;
}

#ifdef CONFIG_PM
static int ahci_port_suspend(struct ata_port *ap, pm_message_t mesg)
{
        const char *emsg = NULL;
        int rc;

        rc = ahci_deinit_port(ap, &emsg);
        if (rc == 0)
                ahci_power_down(ap);
        else {
                ata_port_printk(ap, KERN_ERR, "%s (%d)\n", emsg, rc);
                ahci_start_port(ap);
        }

        return rc;
}

static int ahci_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg)
{
        struct ata_host *host = dev_get_drvdata(&pdev->dev);
        void __iomem *mmio = host->iomap[AHCI_PCI_BAR];
        u32 ctl;

        if (mesg.event & PM_EVENT_SLEEP) {
                /* AHCI spec rev1.1 section 8.3.3:
                 * Software must disable interrupts prior to requesting a
                 * transition of the HBA to D3 state.
                 */
                ctl = readl(mmio + HOST_CTL);
                ctl &= ~HOST_IRQ_EN;
                writel(ctl, mmio + HOST_CTL);
                readl(mmio + HOST_CTL); /* flush */
        }

        return ata_pci_device_suspend(pdev, mesg);
}

static int ahci_pci_device_resume(struct pci_dev *pdev)
{
        struct ata_host *host = dev_get_drvdata(&pdev->dev);
        int rc;

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

        if (pdev->dev.power.power_state.event == PM_EVENT_SUSPEND) {
                rc = ahci_reset_controller(host);
                if (rc)
                        return rc;

                ahci_init_controller(host);
        }

        ata_host_resume(host);

        return 0;
}
#endif

static int ahci_port_start(struct ata_port *ap)
{
        struct device *dev = ap->host->dev;
        struct ahci_port_priv *pp;
        void *mem;
        dma_addr_t mem_dma;

        pp = devm_kzalloc(dev, sizeof(*pp), GFP_KERNEL);
        if (!pp)
                return -ENOMEM;

        mem = dmam_alloc_coherent(dev, AHCI_PORT_PRIV_DMA_SZ, &mem_dma,
                                  GFP_KERNEL);
        if (!mem)
                return -ENOMEM;
        memset(mem, 0, AHCI_PORT_PRIV_DMA_SZ);

        /*
         * First item in chunk of DMA memory: 32-slot command table,
         * 32 bytes each in size
         */
        pp->cmd_slot = mem;
        pp->cmd_slot_dma = mem_dma;

        mem += AHCI_CMD_SLOT_SZ;
        mem_dma += AHCI_CMD_SLOT_SZ;

        /*
         * Second item: Received-FIS area
         */
        pp->rx_fis = mem;
        pp->rx_fis_dma = mem_dma;

        mem += AHCI_RX_FIS_SZ;
        mem_dma += AHCI_RX_FIS_SZ;

        /*
         * Third item: data area for storing a single command
         * and its scatter-gather table
         */
        pp->cmd_tbl = mem;
        pp->cmd_tbl_dma = mem_dma;

        /*
         * Save off initial list of interrupts to be enabled.
         * This could be changed later
         */
        pp->intr_mask = DEF_PORT_IRQ;

        ap->private_data = pp;

        /* engage engines, captain */
        return ahci_port_resume(ap);
}

static void ahci_port_stop(struct ata_port *ap)
{
        const char *emsg = NULL;
        int rc;

        /* de-initialize port */
        rc = ahci_deinit_port(ap, &emsg);
        if (rc)
                ata_port_printk(ap, KERN_WARNING, "%s (%d)\n", emsg, rc);
}

static int ahci_configure_dma_masks(struct pci_dev *pdev, int using_dac)
{
        int rc;

        if (using_dac &&
            !pci_set_dma_mask(pdev, DMA_64BIT_MASK)) {
                rc = pci_set_consistent_dma_mask(pdev, DMA_64BIT_MASK);
                if (rc) {
                        rc = pci_set_consistent_dma_mask(pdev, DMA_32BIT_MASK);
                        if (rc) {
                                dev_printk(KERN_ERR, &pdev->dev,
                                           "64-bit DMA enable failed\n");
                                return rc;
                        }
                }
        } else {
                rc = pci_set_dma_mask(pdev, DMA_32BIT_MASK);
                if (rc) {
                        dev_printk(KERN_ERR, &pdev->dev,
                                   "32-bit DMA enable failed\n");
                        return rc;
                }
                rc = pci_set_consistent_dma_mask(pdev, DMA_32BIT_MASK);
                if (rc) {
                        dev_printk(KERN_ERR, &pdev->dev,
                                   "32-bit consistent DMA enable failed\n");
                        return rc;
                }
        }
        return 0;
}

static void ahci_print_info(struct ata_host *host)
{
        struct ahci_host_priv *hpriv = host->private_data;
        struct pci_dev *pdev = to_pci_dev(host->dev);
        void __iomem *mmio = host->iomap[AHCI_PCI_BAR];
        u32 vers, cap, impl, speed;
        const char *speed_s;
        u16 cc;
        const char *scc_s;

        vers = readl(mmio + HOST_VERSION);
        cap = hpriv->cap;
        impl = hpriv->port_map;

        speed = (cap >> 20) & 0xf;
        if (speed == 1)
                speed_s = "1.5";
        else if (speed == 2)
                speed_s = "3";
        else
                speed_s = "?";

        pci_read_config_word(pdev, 0x0a, &cc);
        if (cc == PCI_CLASS_STORAGE_IDE)
                scc_s = "IDE";
        else if (cc == PCI_CLASS_STORAGE_SATA)
                scc_s = "SATA";
        else if (cc == PCI_CLASS_STORAGE_RAID)
                scc_s = "RAID";
        else
                scc_s = "unknown";

        dev_printk(KERN_INFO, &pdev->dev,
                "AHCI %02x%02x.%02x%02x "
                "%u slots %u ports %s Gbps 0x%x impl %s mode\n"
                ,

                (vers >> 24) & 0xff,
                (vers >> 16) & 0xff,
                (vers >> 8) & 0xff,
                vers & 0xff,

                ((cap >> 8) & 0x1f) + 1,
                (cap & 0x1f) + 1,
                speed_s,
                impl,
                scc_s);

        dev_printk(KERN_INFO, &pdev->dev,
                "flags: "
                "%s%s%s%s%s%s%s"
                "%s%s%s%s%s%s%s\n"
                ,

                cap & (1 << 31) ? "64bit " : "",
                cap & (1 << 30) ? "ncq " : "",
                cap & (1 << 29) ? "sntf " : "",
                cap & (1 << 28) ? "ilck " : "",
                cap & (1 << 27) ? "stag " : "",
                cap & (1 << 26) ? "pm " : "",
                cap & (1 << 25) ? "led " : "",

                cap & (1 << 24) ? "clo " : "",
                cap & (1 << 19) ? "nz " : "",
                cap & (1 << 18) ? "only " : "",
                cap & (1 << 17) ? "pmp " : "",
                cap & (1 << 15) ? "pio " : "",
                cap & (1 << 14) ? "slum " : "",
                cap & (1 << 13) ? "part " : ""
                );
}

/* On ASUS P5W DH Deluxe, the second port of PCI device 00:1f.2 is
 * hardwired to on-board SIMG 4726.  The chipset is ICH8 and doesn't
 * support PMP and the 4726 either directly exports the device
 * attached to the first downstream port or acts as a hardware storage
 * controller and emulate a single ATA device (can be RAID 0/1 or some
 * other configuration).
 *
 * When there's no device attached to the first downstream port of the
 * 4726, "Config Disk" appears, which is a pseudo ATA device to
 * configure the 4726.  However, ATA emulation of the device is very
 * lame.  It doesn't send signature D2H Reg FIS after the initial
 * hardreset, pukes on SRST w/ PMP==0 and has bunch of other issues.
 *
 * The following function works around the problem by always using
 * hardreset on the port and not depending on receiving signature FIS
 * afterward.  If signature FIS isn't received soon, ATA class is
 * assumed without follow-up softreset.
 */
static void ahci_p5wdh_workaround(struct ata_host *host)
{
        static struct dmi_system_id sysids[] = {
                {
                        .ident = "P5W DH Deluxe",
                        .matches = {
                                DMI_MATCH(DMI_SYS_VENDOR,
                                          "ASUSTEK COMPUTER INC"),
                                DMI_MATCH(DMI_PRODUCT_NAME, "P5W DH Deluxe"),
                        },
                },
                { }
        };
        struct pci_dev *pdev = to_pci_dev(host->dev);

        if (pdev->bus->number == 0 && pdev->devfn == PCI_DEVFN(0x1f, 2) &&
            dmi_check_system(sysids)) {
                struct ata_port *ap = host->ports[1];

                dev_printk(KERN_INFO, &pdev->dev, "enabling ASUS P5W DH "
                           "Deluxe on-board SIMG4726 workaround\n");

                ap->ops = &ahci_p5wdh_ops;
                ap->link.flags |= ATA_LFLAG_NO_SRST | ATA_LFLAG_ASSUME_ATA;
        }
}

static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
{
        static int printed_version;
        struct ata_port_info pi = ahci_port_info[ent->driver_data];
        const struct ata_port_info *ppi[] = { &pi, NULL };
        struct device *dev = &pdev->dev;
        struct ahci_host_priv *hpriv;
        struct ata_host *host;
        int n_ports, i, rc;

        VPRINTK("ENTER\n");

        WARN_ON(ATA_MAX_QUEUE > AHCI_MAX_CMDS);

        if (!printed_version++)
                dev_printk(KERN_DEBUG, &pdev->dev, "version " DRV_VERSION "\n");

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

        /* AHCI controllers often implement SFF compatible interface.
         * Grab all PCI BARs just in case.
         */
        rc = pcim_iomap_regions_request_all(pdev, 1 << AHCI_PCI_BAR, DRV_NAME);
        if (rc == -EBUSY)
                pcim_pin_device(pdev);
        if (rc)
                return rc;

        if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
            (pdev->device == 0x2652 || pdev->device == 0x2653)) {
                u8 map;

                /* ICH6s share the same PCI ID for both piix and ahci
                 * modes.  Enabling ahci mode while MAP indicates
                 * combined mode is a bad idea.  Yield to ata_piix.
                 */
                pci_read_config_byte(pdev, ICH_MAP, &map);
                if (map & 0x3) {
                        dev_printk(KERN_INFO, &pdev->dev, "controller is in "
                                   "combined mode, can't enable AHCI mode\n");
                        return -ENODEV;
                }
        }

        hpriv = devm_kzalloc(dev, sizeof(*hpriv), GFP_KERNEL);
        if (!hpriv)
                return -ENOMEM;
        hpriv->flags |= (unsigned long)pi.private_data;

        if ((hpriv->flags & AHCI_HFLAG_NO_MSI) || pci_enable_msi(pdev))
                pci_intx(pdev, 1);

        /* save initial config */
        ahci_save_initial_config(pdev, hpriv);

        /* prepare host */
        if (hpriv->cap & HOST_CAP_NCQ)
                pi.flags |= ATA_FLAG_NCQ;

        if (hpriv->cap & HOST_CAP_PMP)
                pi.flags |= ATA_FLAG_PMP;

        /* CAP.NP sometimes indicate the index of the last enabled
         * port, at other times, that of the last possible port, so
         * determining the maximum port number requires looking at
         * both CAP.NP and port_map.
         */
        n_ports = max(ahci_nr_ports(hpriv->cap), fls(hpriv->port_map));

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

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

                ata_port_pbar_desc(ap, AHCI_PCI_BAR, -1, "abar");
                ata_port_pbar_desc(ap, AHCI_PCI_BAR,
                                   0x100 + ap->port_no * 0x80, "port");

                /* set initial link pm policy */
                ap->pm_policy = NOT_AVAILABLE;

                /* disabled/not-implemented port */
                if (!(hpriv->port_map & (1 << i)))
                        ap->ops = &ata_dummy_port_ops;
        }

        /* apply workaround for ASUS P5W DH Deluxe mainboard */
        ahci_p5wdh_workaround(host);

        /* initialize adapter */
        rc = ahci_configure_dma_masks(pdev, hpriv->cap & HOST_CAP_64);
        if (rc)
                return rc;

        rc = ahci_reset_controller(host);
        if (rc)
                return rc;

        ahci_init_controller(host);
        ahci_print_info(host);

        pci_set_master(pdev);
        return ata_host_activate(host, pdev->irq, ahci_interrupt, IRQF_SHARED,
                                 &ahci_sht);
}

static int __init ahci_init(void)
{
        return pci_register_driver(&ahci_pci_driver);
}

static void __exit ahci_exit(void)
{
        pci_unregister_driver(&ahci_pci_driver);
}


MODULE_AUTHOR("Jeff Garzik");
MODULE_DESCRIPTION("AHCI SATA low-level driver");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, ahci_pci_tbl);
MODULE_VERSION(DRV_VERSION);

module_init(ahci_init);
module_exit(ahci_exit);