libata: convert to chained sg

[safe/jmp/linux-2.6] / drivers / ata / sata_sil24.c

/*
 * sata_sil24.c - Driver for Silicon Image 3124/3132 SATA-2 controllers
 *
 * Copyright 2005  Tejun Heo
 *
 * Based on preview driver from Silicon Image.
 *
 * 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.
 *
 */

#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/dma-mapping.h>
#include <linux/device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_cmnd.h>
#include <linux/libata.h>

#define DRV_NAME        "sata_sil24"
#define DRV_VERSION     "1.1"

/*
 * Port request block (PRB) 32 bytes
 */
struct sil24_prb {
        __le16  ctrl;
        __le16  prot;
        __le32  rx_cnt;
        u8      fis[6 * 4];
};

/*
 * Scatter gather entry (SGE) 16 bytes
 */
struct sil24_sge {
        __le64  addr;
        __le32  cnt;
        __le32  flags;
};

/*
 * Port multiplier
 */
struct sil24_port_multiplier {
        __le32  diag;
        __le32  sactive;
};

enum {
        SIL24_HOST_BAR          = 0,
        SIL24_PORT_BAR          = 2,

        /* sil24 fetches in chunks of 64bytes.  The first block
         * contains the PRB and two SGEs.  From the second block, it's
         * consisted of four SGEs and called SGT.  Calculate the
         * number of SGTs that fit into one page.
         */
        SIL24_PRB_SZ            = sizeof(struct sil24_prb)
                                  + 2 * sizeof(struct sil24_sge),
        SIL24_MAX_SGT           = (PAGE_SIZE - SIL24_PRB_SZ)
                                  / (4 * sizeof(struct sil24_sge)),

        /* This will give us one unused SGEs for ATA.  This extra SGE
         * will be used to store CDB for ATAPI devices.
         */
        SIL24_MAX_SGE           = 4 * SIL24_MAX_SGT + 1,

        /*
         * Global controller registers (128 bytes @ BAR0)
         */
                /* 32 bit regs */
        HOST_SLOT_STAT          = 0x00, /* 32 bit slot stat * 4 */
        HOST_CTRL               = 0x40,
        HOST_IRQ_STAT           = 0x44,
        HOST_PHY_CFG            = 0x48,
        HOST_BIST_CTRL          = 0x50,
        HOST_BIST_PTRN          = 0x54,
        HOST_BIST_STAT          = 0x58,
        HOST_MEM_BIST_STAT      = 0x5c,
        HOST_FLASH_CMD          = 0x70,
                /* 8 bit regs */
        HOST_FLASH_DATA         = 0x74,
        HOST_TRANSITION_DETECT  = 0x75,
        HOST_GPIO_CTRL          = 0x76,
        HOST_I2C_ADDR           = 0x78, /* 32 bit */
        HOST_I2C_DATA           = 0x7c,
        HOST_I2C_XFER_CNT       = 0x7e,
        HOST_I2C_CTRL           = 0x7f,

        /* HOST_SLOT_STAT bits */
        HOST_SSTAT_ATTN         = (1 << 31),

        /* HOST_CTRL bits */
        HOST_CTRL_M66EN         = (1 << 16), /* M66EN PCI bus signal */
        HOST_CTRL_TRDY          = (1 << 17), /* latched PCI TRDY */
        HOST_CTRL_STOP          = (1 << 18), /* latched PCI STOP */
        HOST_CTRL_DEVSEL        = (1 << 19), /* latched PCI DEVSEL */
        HOST_CTRL_REQ64         = (1 << 20), /* latched PCI REQ64 */
        HOST_CTRL_GLOBAL_RST    = (1 << 31), /* global reset */

        /*
         * Port registers
         * (8192 bytes @ +0x0000, +0x2000, +0x4000 and +0x6000 @ BAR2)
         */
        PORT_REGS_SIZE          = 0x2000,

        PORT_LRAM               = 0x0000, /* 31 LRAM slots and PMP regs */
        PORT_LRAM_SLOT_SZ       = 0x0080, /* 32 bytes PRB + 2 SGE, ACT... */

        PORT_PMP                = 0x0f80, /* 8 bytes PMP * 16 (128 bytes) */
        PORT_PMP_STATUS         = 0x0000, /* port device status offset */
        PORT_PMP_QACTIVE        = 0x0004, /* port device QActive offset */
        PORT_PMP_SIZE           = 0x0008, /* 8 bytes per PMP */

                /* 32 bit regs */
        PORT_CTRL_STAT          = 0x1000, /* write: ctrl-set, read: stat */
        PORT_CTRL_CLR           = 0x1004, /* write: ctrl-clear */
        PORT_IRQ_STAT           = 0x1008, /* high: status, low: interrupt */
        PORT_IRQ_ENABLE_SET     = 0x1010, /* write: enable-set */
        PORT_IRQ_ENABLE_CLR     = 0x1014, /* write: enable-clear */
        PORT_ACTIVATE_UPPER_ADDR= 0x101c,
        PORT_EXEC_FIFO          = 0x1020, /* command execution fifo */
        PORT_CMD_ERR            = 0x1024, /* command error number */
        PORT_FIS_CFG            = 0x1028,
        PORT_FIFO_THRES         = 0x102c,
                /* 16 bit regs */
        PORT_DECODE_ERR_CNT     = 0x1040,
        PORT_DECODE_ERR_THRESH  = 0x1042,
        PORT_CRC_ERR_CNT        = 0x1044,
        PORT_CRC_ERR_THRESH     = 0x1046,
        PORT_HSHK_ERR_CNT       = 0x1048,
        PORT_HSHK_ERR_THRESH    = 0x104a,
                /* 32 bit regs */
        PORT_PHY_CFG            = 0x1050,
        PORT_SLOT_STAT          = 0x1800,
        PORT_CMD_ACTIVATE       = 0x1c00, /* 64 bit cmd activate * 31 (248 bytes) */
        PORT_CONTEXT            = 0x1e04,
        PORT_EXEC_DIAG          = 0x1e00, /* 32bit exec diag * 16 (64 bytes, 0-10 used on 3124) */
        PORT_PSD_DIAG           = 0x1e40, /* 32bit psd diag * 16 (64 bytes, 0-8 used on 3124) */
        PORT_SCONTROL           = 0x1f00,
        PORT_SSTATUS            = 0x1f04,
        PORT_SERROR             = 0x1f08,
        PORT_SACTIVE            = 0x1f0c,

        /* PORT_CTRL_STAT bits */
        PORT_CS_PORT_RST        = (1 << 0), /* port reset */
        PORT_CS_DEV_RST         = (1 << 1), /* device reset */
        PORT_CS_INIT            = (1 << 2), /* port initialize */
        PORT_CS_IRQ_WOC         = (1 << 3), /* interrupt write one to clear */
        PORT_CS_CDB16           = (1 << 5), /* 0=12b cdb, 1=16b cdb */
        PORT_CS_PMP_RESUME      = (1 << 6), /* PMP resume */
        PORT_CS_32BIT_ACTV      = (1 << 10), /* 32-bit activation */
        PORT_CS_PMP_EN          = (1 << 13), /* port multiplier enable */
        PORT_CS_RDY             = (1 << 31), /* port ready to accept commands */

        /* PORT_IRQ_STAT/ENABLE_SET/CLR */
        /* bits[11:0] are masked */
        PORT_IRQ_COMPLETE       = (1 << 0), /* command(s) completed */
        PORT_IRQ_ERROR          = (1 << 1), /* command execution error */
        PORT_IRQ_PORTRDY_CHG    = (1 << 2), /* port ready change */
        PORT_IRQ_PWR_CHG        = (1 << 3), /* power management change */
        PORT_IRQ_PHYRDY_CHG     = (1 << 4), /* PHY ready change */
        PORT_IRQ_COMWAKE        = (1 << 5), /* COMWAKE received */
        PORT_IRQ_UNK_FIS        = (1 << 6), /* unknown FIS received */
        PORT_IRQ_DEV_XCHG       = (1 << 7), /* device exchanged */
        PORT_IRQ_8B10B          = (1 << 8), /* 8b/10b decode error threshold */
        PORT_IRQ_CRC            = (1 << 9), /* CRC error threshold */
        PORT_IRQ_HANDSHAKE      = (1 << 10), /* handshake error threshold */
        PORT_IRQ_SDB_NOTIFY     = (1 << 11), /* SDB notify received */

        DEF_PORT_IRQ            = PORT_IRQ_COMPLETE | PORT_IRQ_ERROR |
                                  PORT_IRQ_PHYRDY_CHG | PORT_IRQ_DEV_XCHG |
                                  PORT_IRQ_UNK_FIS | PORT_IRQ_SDB_NOTIFY,

        /* bits[27:16] are unmasked (raw) */
        PORT_IRQ_RAW_SHIFT      = 16,
        PORT_IRQ_MASKED_MASK    = 0x7ff,
        PORT_IRQ_RAW_MASK       = (0x7ff << PORT_IRQ_RAW_SHIFT),

        /* ENABLE_SET/CLR specific, intr steering - 2 bit field */
        PORT_IRQ_STEER_SHIFT    = 30,
        PORT_IRQ_STEER_MASK     = (3 << PORT_IRQ_STEER_SHIFT),

        /* PORT_CMD_ERR constants */
        PORT_CERR_DEV           = 1, /* Error bit in D2H Register FIS */
        PORT_CERR_SDB           = 2, /* Error bit in SDB FIS */
        PORT_CERR_DATA          = 3, /* Error in data FIS not detected by dev */
        PORT_CERR_SEND          = 4, /* Initial cmd FIS transmission failure */
        PORT_CERR_INCONSISTENT  = 5, /* Protocol mismatch */
        PORT_CERR_DIRECTION     = 6, /* Data direction mismatch */
        PORT_CERR_UNDERRUN      = 7, /* Ran out of SGEs while writing */
        PORT_CERR_OVERRUN       = 8, /* Ran out of SGEs while reading */
        PORT_CERR_PKT_PROT      = 11, /* DIR invalid in 1st PIO setup of ATAPI */
        PORT_CERR_SGT_BOUNDARY  = 16, /* PLD ecode 00 - SGT not on qword boundary */
        PORT_CERR_SGT_TGTABRT   = 17, /* PLD ecode 01 - target abort */
        PORT_CERR_SGT_MSTABRT   = 18, /* PLD ecode 10 - master abort */
        PORT_CERR_SGT_PCIPERR   = 19, /* PLD ecode 11 - PCI parity err while fetching SGT */
        PORT_CERR_CMD_BOUNDARY  = 24, /* ctrl[15:13] 001 - PRB not on qword boundary */
        PORT_CERR_CMD_TGTABRT   = 25, /* ctrl[15:13] 010 - target abort */
        PORT_CERR_CMD_MSTABRT   = 26, /* ctrl[15:13] 100 - master abort */
        PORT_CERR_CMD_PCIPERR   = 27, /* ctrl[15:13] 110 - PCI parity err while fetching PRB */
        PORT_CERR_XFR_UNDEF     = 32, /* PSD ecode 00 - undefined */
        PORT_CERR_XFR_TGTABRT   = 33, /* PSD ecode 01 - target abort */
        PORT_CERR_XFR_MSTABRT   = 34, /* PSD ecode 10 - master abort */
        PORT_CERR_XFR_PCIPERR   = 35, /* PSD ecode 11 - PCI prity err during transfer */
        PORT_CERR_SENDSERVICE   = 36, /* FIS received while sending service */

        /* bits of PRB control field */
        PRB_CTRL_PROTOCOL       = (1 << 0), /* override def. ATA protocol */
        PRB_CTRL_PACKET_READ    = (1 << 4), /* PACKET cmd read */
        PRB_CTRL_PACKET_WRITE   = (1 << 5), /* PACKET cmd write */
        PRB_CTRL_NIEN           = (1 << 6), /* Mask completion irq */
        PRB_CTRL_SRST           = (1 << 7), /* Soft reset request (ign BSY?) */

        /* PRB protocol field */
        PRB_PROT_PACKET         = (1 << 0),
        PRB_PROT_TCQ            = (1 << 1),
        PRB_PROT_NCQ            = (1 << 2),
        PRB_PROT_READ           = (1 << 3),
        PRB_PROT_WRITE          = (1 << 4),
        PRB_PROT_TRANSPARENT    = (1 << 5),

        /*
         * Other constants
         */
        SGE_TRM                 = (1 << 31), /* Last SGE in chain */
        SGE_LNK                 = (1 << 30), /* linked list
                                                Points to SGT, not SGE */
        SGE_DRD                 = (1 << 29), /* discard data read (/dev/null)
                                                data address ignored */

        SIL24_MAX_CMDS          = 31,

        /* board id */
        BID_SIL3124             = 0,
        BID_SIL3132             = 1,
        BID_SIL3131             = 2,

        /* host flags */
        SIL24_COMMON_FLAGS      = ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
                                  ATA_FLAG_MMIO | ATA_FLAG_PIO_DMA |
                                  ATA_FLAG_NCQ | ATA_FLAG_ACPI_SATA |
                                  ATA_FLAG_AN | ATA_FLAG_PMP,
        SIL24_COMMON_LFLAGS     = ATA_LFLAG_SKIP_D2H_BSY,
        SIL24_FLAG_PCIX_IRQ_WOC = (1 << 24), /* IRQ loss errata on PCI-X */

        IRQ_STAT_4PORTS         = 0xf,
};

struct sil24_ata_block {
        struct sil24_prb prb;
        struct sil24_sge sge[SIL24_MAX_SGE];
};

struct sil24_atapi_block {
        struct sil24_prb prb;
        u8 cdb[16];
        struct sil24_sge sge[SIL24_MAX_SGE];
};

union sil24_cmd_block {
        struct sil24_ata_block ata;
        struct sil24_atapi_block atapi;
};

static struct sil24_cerr_info {
        unsigned int err_mask, action;
        const char *desc;
} sil24_cerr_db[] = {
        [0]                     = { AC_ERR_DEV, 0,
                                    "device error" },
        [PORT_CERR_DEV]         = { AC_ERR_DEV, 0,
                                    "device error via D2H FIS" },
        [PORT_CERR_SDB]         = { AC_ERR_DEV, 0,
                                    "device error via SDB FIS" },
        [PORT_CERR_DATA]        = { AC_ERR_ATA_BUS, ATA_EH_SOFTRESET,
                                    "error in data FIS" },
        [PORT_CERR_SEND]        = { AC_ERR_ATA_BUS, ATA_EH_SOFTRESET,
                                    "failed to transmit command FIS" },
        [PORT_CERR_INCONSISTENT] = { AC_ERR_HSM, ATA_EH_SOFTRESET,
                                     "protocol mismatch" },
        [PORT_CERR_DIRECTION]   = { AC_ERR_HSM, ATA_EH_SOFTRESET,
                                    "data directon mismatch" },
        [PORT_CERR_UNDERRUN]    = { AC_ERR_HSM, ATA_EH_SOFTRESET,
                                    "ran out of SGEs while writing" },
        [PORT_CERR_OVERRUN]     = { AC_ERR_HSM, ATA_EH_SOFTRESET,
                                    "ran out of SGEs while reading" },
        [PORT_CERR_PKT_PROT]    = { AC_ERR_HSM, ATA_EH_SOFTRESET,
                                    "invalid data directon for ATAPI CDB" },
        [PORT_CERR_SGT_BOUNDARY] = { AC_ERR_SYSTEM, ATA_EH_SOFTRESET,
                                     "SGT not on qword boundary" },
        [PORT_CERR_SGT_TGTABRT] = { AC_ERR_HOST_BUS, ATA_EH_SOFTRESET,
                                    "PCI target abort while fetching SGT" },
        [PORT_CERR_SGT_MSTABRT] = { AC_ERR_HOST_BUS, ATA_EH_SOFTRESET,
                                    "PCI master abort while fetching SGT" },
        [PORT_CERR_SGT_PCIPERR] = { AC_ERR_HOST_BUS, ATA_EH_SOFTRESET,
                                    "PCI parity error while fetching SGT" },
        [PORT_CERR_CMD_BOUNDARY] = { AC_ERR_SYSTEM, ATA_EH_SOFTRESET,
                                     "PRB not on qword boundary" },
        [PORT_CERR_CMD_TGTABRT] = { AC_ERR_HOST_BUS, ATA_EH_SOFTRESET,
                                    "PCI target abort while fetching PRB" },
        [PORT_CERR_CMD_MSTABRT] = { AC_ERR_HOST_BUS, ATA_EH_SOFTRESET,
                                    "PCI master abort while fetching PRB" },
        [PORT_CERR_CMD_PCIPERR] = { AC_ERR_HOST_BUS, ATA_EH_SOFTRESET,
                                    "PCI parity error while fetching PRB" },
        [PORT_CERR_XFR_UNDEF]   = { AC_ERR_HOST_BUS, ATA_EH_SOFTRESET,
                                    "undefined error while transferring data" },
        [PORT_CERR_XFR_TGTABRT] = { AC_ERR_HOST_BUS, ATA_EH_SOFTRESET,
                                    "PCI target abort while transferring data" },
        [PORT_CERR_XFR_MSTABRT] = { AC_ERR_HOST_BUS, ATA_EH_SOFTRESET,
                                    "PCI master abort while transferring data" },
        [PORT_CERR_XFR_PCIPERR] = { AC_ERR_HOST_BUS, ATA_EH_SOFTRESET,
                                    "PCI parity error while transferring data" },
        [PORT_CERR_SENDSERVICE] = { AC_ERR_HSM, ATA_EH_SOFTRESET,
                                    "FIS received while sending service FIS" },
};

/*
 * ap->private_data
 *
 * The preview driver always returned 0 for status.  We emulate it
 * here from the previous interrupt.
 */
struct sil24_port_priv {
        union sil24_cmd_block *cmd_block;       /* 32 cmd blocks */
        dma_addr_t cmd_block_dma;               /* DMA base addr for them */
        struct ata_taskfile tf;                 /* Cached taskfile registers */
        int do_port_rst;
};

static void sil24_dev_config(struct ata_device *dev);
static u8 sil24_check_status(struct ata_port *ap);
static int sil24_scr_read(struct ata_port *ap, unsigned sc_reg, u32 *val);
static int sil24_scr_write(struct ata_port *ap, unsigned sc_reg, u32 val);
static void sil24_tf_read(struct ata_port *ap, struct ata_taskfile *tf);
static int sil24_qc_defer(struct ata_queued_cmd *qc);
static void sil24_qc_prep(struct ata_queued_cmd *qc);
static unsigned int sil24_qc_issue(struct ata_queued_cmd *qc);
static void sil24_irq_clear(struct ata_port *ap);
static void sil24_pmp_attach(struct ata_port *ap);
static void sil24_pmp_detach(struct ata_port *ap);
static void sil24_freeze(struct ata_port *ap);
static void sil24_thaw(struct ata_port *ap);
static void sil24_error_handler(struct ata_port *ap);
static void sil24_post_internal_cmd(struct ata_queued_cmd *qc);
static int sil24_port_start(struct ata_port *ap);
static int sil24_init_one(struct pci_dev *pdev, const struct pci_device_id *ent);
#ifdef CONFIG_PM
static int sil24_pci_device_resume(struct pci_dev *pdev);
static int sil24_port_resume(struct ata_port *ap);
#endif

static const struct pci_device_id sil24_pci_tbl[] = {
        { PCI_VDEVICE(CMD, 0x3124), BID_SIL3124 },
        { PCI_VDEVICE(INTEL, 0x3124), BID_SIL3124 },
        { PCI_VDEVICE(CMD, 0x3132), BID_SIL3132 },
        { PCI_VDEVICE(CMD, 0x0242), BID_SIL3132 },
        { PCI_VDEVICE(CMD, 0x3131), BID_SIL3131 },
        { PCI_VDEVICE(CMD, 0x3531), BID_SIL3131 },

        { } /* terminate list */
};

static struct pci_driver sil24_pci_driver = {
        .name                   = DRV_NAME,
        .id_table               = sil24_pci_tbl,
        .probe                  = sil24_init_one,
        .remove                 = ata_pci_remove_one,
#ifdef CONFIG_PM
        .suspend                = ata_pci_device_suspend,
        .resume                 = sil24_pci_device_resume,
#endif
};

static struct scsi_host_template sil24_sht = {
        .module                 = THIS_MODULE,
        .name                   = DRV_NAME,
        .ioctl                  = ata_scsi_ioctl,
        .queuecommand           = ata_scsi_queuecmd,
        .change_queue_depth     = ata_scsi_change_queue_depth,
        .can_queue              = SIL24_MAX_CMDS,
        .this_id                = ATA_SHT_THIS_ID,
        .sg_tablesize           = SIL24_MAX_SGE,
        .cmd_per_lun            = ATA_SHT_CMD_PER_LUN,
        .emulated               = ATA_SHT_EMULATED,
        .use_clustering         = ATA_SHT_USE_CLUSTERING,
        .proc_name              = DRV_NAME,
        .dma_boundary           = ATA_DMA_BOUNDARY,
        .slave_configure        = ata_scsi_slave_config,
        .slave_destroy          = ata_scsi_slave_destroy,
        .bios_param             = ata_std_bios_param,
};

static const struct ata_port_operations sil24_ops = {
        .dev_config             = sil24_dev_config,

        .check_status           = sil24_check_status,
        .check_altstatus        = sil24_check_status,
        .dev_select             = ata_noop_dev_select,

        .tf_read                = sil24_tf_read,

        .qc_defer               = sil24_qc_defer,
        .qc_prep                = sil24_qc_prep,
        .qc_issue               = sil24_qc_issue,

        .irq_clear              = sil24_irq_clear,

        .scr_read               = sil24_scr_read,
        .scr_write              = sil24_scr_write,

        .pmp_attach             = sil24_pmp_attach,
        .pmp_detach             = sil24_pmp_detach,

        .freeze                 = sil24_freeze,
        .thaw                   = sil24_thaw,
        .error_handler          = sil24_error_handler,
        .post_internal_cmd      = sil24_post_internal_cmd,

        .port_start             = sil24_port_start,

#ifdef CONFIG_PM
        .port_resume            = sil24_port_resume,
#endif
};

/*
 * Use bits 30-31 of port_flags to encode available port numbers.
 * Current maxium is 4.
 */
#define SIL24_NPORTS2FLAG(nports)       ((((unsigned)(nports) - 1) & 0x3) << 30)
#define SIL24_FLAG2NPORTS(flag)         ((((flag) >> 30) & 0x3) + 1)

static const struct ata_port_info sil24_port_info[] = {
        /* sil_3124 */
        {
                .flags          = SIL24_COMMON_FLAGS | SIL24_NPORTS2FLAG(4) |
                                  SIL24_FLAG_PCIX_IRQ_WOC,
                .link_flags     = SIL24_COMMON_LFLAGS,
                .pio_mask       = 0x1f,                 /* pio0-4 */
                .mwdma_mask     = 0x07,                 /* mwdma0-2 */
                .udma_mask      = ATA_UDMA5,            /* udma0-5 */
                .port_ops       = &sil24_ops,
        },
        /* sil_3132 */
        {
                .flags          = SIL24_COMMON_FLAGS | SIL24_NPORTS2FLAG(2),
                .link_flags     = SIL24_COMMON_LFLAGS,
                .pio_mask       = 0x1f,                 /* pio0-4 */
                .mwdma_mask     = 0x07,                 /* mwdma0-2 */
                .udma_mask      = ATA_UDMA5,            /* udma0-5 */
                .port_ops       = &sil24_ops,
        },
        /* sil_3131/sil_3531 */
        {
                .flags          = SIL24_COMMON_FLAGS | SIL24_NPORTS2FLAG(1),
                .link_flags     = SIL24_COMMON_LFLAGS,
                .pio_mask       = 0x1f,                 /* pio0-4 */
                .mwdma_mask     = 0x07,                 /* mwdma0-2 */
                .udma_mask      = ATA_UDMA5,            /* udma0-5 */
                .port_ops       = &sil24_ops,
        },
};

static int sil24_tag(int tag)
{
        if (unlikely(ata_tag_internal(tag)))
                return 0;
        return tag;
}

static void sil24_dev_config(struct ata_device *dev)
{
        void __iomem *port = dev->link->ap->ioaddr.cmd_addr;

        if (dev->cdb_len == 16)
                writel(PORT_CS_CDB16, port + PORT_CTRL_STAT);
        else
                writel(PORT_CS_CDB16, port + PORT_CTRL_CLR);
}

static void sil24_read_tf(struct ata_port *ap, int tag, struct ata_taskfile *tf)
{
        void __iomem *port = ap->ioaddr.cmd_addr;
        struct sil24_prb __iomem *prb;
        u8 fis[6 * 4];

        prb = port + PORT_LRAM + sil24_tag(tag) * PORT_LRAM_SLOT_SZ;
        memcpy_fromio(fis, prb->fis, sizeof(fis));
        ata_tf_from_fis(fis, tf);
}

static u8 sil24_check_status(struct ata_port *ap)
{
        struct sil24_port_priv *pp = ap->private_data;
        return pp->tf.command;
}

static int sil24_scr_map[] = {
        [SCR_CONTROL]   = 0,
        [SCR_STATUS]    = 1,
        [SCR_ERROR]     = 2,
        [SCR_ACTIVE]    = 3,
};

static int sil24_scr_read(struct ata_port *ap, unsigned sc_reg, u32 *val)
{
        void __iomem *scr_addr = ap->ioaddr.scr_addr;

        if (sc_reg < ARRAY_SIZE(sil24_scr_map)) {
                void __iomem *addr;
                addr = scr_addr + sil24_scr_map[sc_reg] * 4;
                *val = readl(scr_addr + sil24_scr_map[sc_reg] * 4);
                return 0;
        }
        return -EINVAL;
}

static int sil24_scr_write(struct ata_port *ap, unsigned sc_reg, u32 val)
{
        void __iomem *scr_addr = ap->ioaddr.scr_addr;

        if (sc_reg < ARRAY_SIZE(sil24_scr_map)) {
                void __iomem *addr;
                addr = scr_addr + sil24_scr_map[sc_reg] * 4;
                writel(val, scr_addr + sil24_scr_map[sc_reg] * 4);
                return 0;
        }
        return -EINVAL;
}

static void sil24_tf_read(struct ata_port *ap, struct ata_taskfile *tf)
{
        struct sil24_port_priv *pp = ap->private_data;
        *tf = pp->tf;
}

static void sil24_config_port(struct ata_port *ap)
{
        void __iomem *port = ap->ioaddr.cmd_addr;

        /* configure IRQ WoC */
        if (ap->flags & SIL24_FLAG_PCIX_IRQ_WOC)
                writel(PORT_CS_IRQ_WOC, port + PORT_CTRL_STAT);
        else
                writel(PORT_CS_IRQ_WOC, port + PORT_CTRL_CLR);

        /* zero error counters. */
        writel(0x8000, port + PORT_DECODE_ERR_THRESH);
        writel(0x8000, port + PORT_CRC_ERR_THRESH);
        writel(0x8000, port + PORT_HSHK_ERR_THRESH);
        writel(0x0000, port + PORT_DECODE_ERR_CNT);
        writel(0x0000, port + PORT_CRC_ERR_CNT);
        writel(0x0000, port + PORT_HSHK_ERR_CNT);

        /* always use 64bit activation */
        writel(PORT_CS_32BIT_ACTV, port + PORT_CTRL_CLR);

        /* clear port multiplier enable and resume bits */
        writel(PORT_CS_PMP_EN | PORT_CS_PMP_RESUME, port + PORT_CTRL_CLR);
}

static void sil24_config_pmp(struct ata_port *ap, int attached)
{
        void __iomem *port = ap->ioaddr.cmd_addr;

        if (attached)
                writel(PORT_CS_PMP_EN, port + PORT_CTRL_STAT);
        else
                writel(PORT_CS_PMP_EN, port + PORT_CTRL_CLR);
}

static void sil24_clear_pmp(struct ata_port *ap)
{
        void __iomem *port = ap->ioaddr.cmd_addr;
        int i;

        writel(PORT_CS_PMP_RESUME, port + PORT_CTRL_CLR);

        for (i = 0; i < SATA_PMP_MAX_PORTS; i++) {
                void __iomem *pmp_base = port + PORT_PMP + i * PORT_PMP_SIZE;

                writel(0, pmp_base + PORT_PMP_STATUS);
                writel(0, pmp_base + PORT_PMP_QACTIVE);
        }
}

static int sil24_init_port(struct ata_port *ap)
{
        void __iomem *port = ap->ioaddr.cmd_addr;
        struct sil24_port_priv *pp = ap->private_data;
        u32 tmp;

        /* clear PMP error status */
        if (ap->nr_pmp_links)
                sil24_clear_pmp(ap);

        writel(PORT_CS_INIT, port + PORT_CTRL_STAT);
        ata_wait_register(port + PORT_CTRL_STAT,
                          PORT_CS_INIT, PORT_CS_INIT, 10, 100);
        tmp = ata_wait_register(port + PORT_CTRL_STAT,
                                PORT_CS_RDY, 0, 10, 100);

        if ((tmp & (PORT_CS_INIT | PORT_CS_RDY)) != PORT_CS_RDY) {
                pp->do_port_rst = 1;
                ap->link.eh_context.i.action |= ATA_EH_HARDRESET;
                return -EIO;
        }

        return 0;
}

static int sil24_exec_polled_cmd(struct ata_port *ap, int pmp,
                                 const struct ata_taskfile *tf,
                                 int is_cmd, u32 ctrl,
                                 unsigned long timeout_msec)
{
        void __iomem *port = ap->ioaddr.cmd_addr;
        struct sil24_port_priv *pp = ap->private_data;
        struct sil24_prb *prb = &pp->cmd_block[0].ata.prb;
        dma_addr_t paddr = pp->cmd_block_dma;
        u32 irq_enabled, irq_mask, irq_stat;
        int rc;

        prb->ctrl = cpu_to_le16(ctrl);
        ata_tf_to_fis(tf, pmp, is_cmd, prb->fis);

        /* temporarily plug completion and error interrupts */
        irq_enabled = readl(port + PORT_IRQ_ENABLE_SET);
        writel(PORT_IRQ_COMPLETE | PORT_IRQ_ERROR, port + PORT_IRQ_ENABLE_CLR);

        writel((u32)paddr, port + PORT_CMD_ACTIVATE);
        writel((u64)paddr >> 32, port + PORT_CMD_ACTIVATE + 4);

        irq_mask = (PORT_IRQ_COMPLETE | PORT_IRQ_ERROR) << PORT_IRQ_RAW_SHIFT;
        irq_stat = ata_wait_register(port + PORT_IRQ_STAT, irq_mask, 0x0,
                                     10, timeout_msec);

        writel(irq_mask, port + PORT_IRQ_STAT); /* clear IRQs */
        irq_stat >>= PORT_IRQ_RAW_SHIFT;

        if (irq_stat & PORT_IRQ_COMPLETE)
                rc = 0;
        else {
                /* force port into known state */
                sil24_init_port(ap);

                if (irq_stat & PORT_IRQ_ERROR)
                        rc = -EIO;
                else
                        rc = -EBUSY;
        }

        /* restore IRQ enabled */
        writel(irq_enabled, port + PORT_IRQ_ENABLE_SET);

        return rc;
}

static int sil24_do_softreset(struct ata_link *link, unsigned int *class,
                              int pmp, unsigned long deadline)
{
        struct ata_port *ap = link->ap;
        unsigned long timeout_msec = 0;
        struct ata_taskfile tf;
        const char *reason;
        int rc;

        DPRINTK("ENTER\n");

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

        /* put the port into known state */
        if (sil24_init_port(ap)) {
                reason = "port not ready";
                goto err;
        }

        /* do SRST */
        if (time_after(deadline, jiffies))
                timeout_msec = jiffies_to_msecs(deadline - jiffies);

        ata_tf_init(link->device, &tf); /* doesn't really matter */
        rc = sil24_exec_polled_cmd(ap, pmp, &tf, 0, PRB_CTRL_SRST,
                                   timeout_msec);
        if (rc == -EBUSY) {
                reason = "timeout";
                goto err;
        } else if (rc) {
                reason = "SRST command error";
                goto err;
        }

        sil24_read_tf(ap, 0, &tf);
        *class = ata_dev_classify(&tf);

        if (*class == ATA_DEV_UNKNOWN)
                *class = ATA_DEV_NONE;

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

 err:
        ata_link_printk(link, KERN_ERR, "softreset failed (%s)\n", reason);
        return -EIO;
}

static int sil24_softreset(struct ata_link *link, unsigned int *class,
                           unsigned long deadline)
{
        return sil24_do_softreset(link, class, SATA_PMP_CTRL_PORT, deadline);
}

static int sil24_hardreset(struct ata_link *link, unsigned int *class,
                           unsigned long deadline)
{
        struct ata_port *ap = link->ap;
        void __iomem *port = ap->ioaddr.cmd_addr;
        struct sil24_port_priv *pp = ap->private_data;
        int did_port_rst = 0;
        const char *reason;
        int tout_msec, rc;
        u32 tmp;

 retry:
        /* Sometimes, DEV_RST is not enough to recover the controller.
         * This happens often after PM DMA CS errata.
         */
        if (pp->do_port_rst) {
                ata_port_printk(ap, KERN_WARNING, "controller in dubious "
                                "state, performing PORT_RST\n");

                writel(PORT_CS_PORT_RST, port + PORT_CTRL_STAT);
                msleep(10);
                writel(PORT_CS_PORT_RST, port + PORT_CTRL_CLR);
                ata_wait_register(port + PORT_CTRL_STAT, PORT_CS_RDY, 0,
                                  10, 5000);

                /* restore port configuration */
                sil24_config_port(ap);
                sil24_config_pmp(ap, ap->nr_pmp_links);

                pp->do_port_rst = 0;
                did_port_rst = 1;
        }

        /* sil24 does the right thing(tm) without any protection */
        sata_set_spd(link);

        tout_msec = 100;
        if (ata_link_online(link))
                tout_msec = 5000;

        writel(PORT_CS_DEV_RST, port + PORT_CTRL_STAT);
        tmp = ata_wait_register(port + PORT_CTRL_STAT,
                                PORT_CS_DEV_RST, PORT_CS_DEV_RST, 10,
                                tout_msec);

        /* SStatus oscillates between zero and valid status after
         * DEV_RST, debounce it.
         */
        rc = sata_link_debounce(link, sata_deb_timing_long, deadline);
        if (rc) {
                reason = "PHY debouncing failed";
                goto err;
        }

        if (tmp & PORT_CS_DEV_RST) {
                if (ata_link_offline(link))
                        return 0;
                reason = "link not ready";
                goto err;
        }

        /* Sil24 doesn't store signature FIS after hardreset, so we
         * can't wait for BSY to clear.  Some devices take a long time
         * to get ready and those devices will choke if we don't wait
         * for BSY clearance here.  Tell libata to perform follow-up
         * softreset.
         */
        return -EAGAIN;

 err:
        if (!did_port_rst) {
                pp->do_port_rst = 1;
                goto retry;
        }

        ata_link_printk(link, KERN_ERR, "hardreset failed (%s)\n", reason);
        return -EIO;
}

static inline void sil24_fill_sg(struct ata_queued_cmd *qc,
                                 struct sil24_sge *sge)
{
        struct scatterlist *sg;
        struct sil24_sge *last_sge = NULL;
        unsigned int si;

        for_each_sg(qc->sg, sg, qc->n_elem, si) {
                sge->addr = cpu_to_le64(sg_dma_address(sg));
                sge->cnt = cpu_to_le32(sg_dma_len(sg));
                sge->flags = 0;

                last_sge = sge;
                sge++;
        }

        last_sge->flags = cpu_to_le32(SGE_TRM);
}

static int sil24_qc_defer(struct ata_queued_cmd *qc)
{
        struct ata_link *link = qc->dev->link;
        struct ata_port *ap = link->ap;
        u8 prot = qc->tf.protocol;

        /*
         * There is a bug in the chip:
         * Port LRAM Causes the PRB/SGT Data to be Corrupted
         * If the host issues a read request for LRAM and SActive registers
         * while active commands are available in the port, PRB/SGT data in
         * the LRAM can become corrupted. This issue applies only when
         * reading from, but not writing to, the LRAM.
         *
         * Therefore, reading LRAM when there is no particular error [and
         * other commands may be outstanding] is prohibited.
         *
         * To avoid this bug there are two situations where a command must run
         * exclusive of any other commands on the port:
         *
         * - ATAPI commands which check the sense data
         * - Passthrough ATA commands which always have ATA_QCFLAG_RESULT_TF
         *   set.
         *
         */
        int is_excl = (ata_is_atapi(prot) ||
                       (qc->flags & ATA_QCFLAG_RESULT_TF));

        if (unlikely(ap->excl_link)) {
                if (link == ap->excl_link) {
                        if (ap->nr_active_links)
                                return ATA_DEFER_PORT;
                        qc->flags |= ATA_QCFLAG_CLEAR_EXCL;
                } else
                        return ATA_DEFER_PORT;
        } else if (unlikely(is_excl)) {
                ap->excl_link = link;
                if (ap->nr_active_links)
                        return ATA_DEFER_PORT;
                qc->flags |= ATA_QCFLAG_CLEAR_EXCL;
        }

        return ata_std_qc_defer(qc);
}

static void sil24_qc_prep(struct ata_queued_cmd *qc)
{
        struct ata_port *ap = qc->ap;
        struct sil24_port_priv *pp = ap->private_data;
        union sil24_cmd_block *cb;
        struct sil24_prb *prb;
        struct sil24_sge *sge;
        u16 ctrl = 0;

        cb = &pp->cmd_block[sil24_tag(qc->tag)];

        if (!ata_is_atapi(qc->tf.protocol)) {
                prb = &cb->ata.prb;
                sge = cb->ata.sge;
        } else {
                prb = &cb->atapi.prb;
                sge = cb->atapi.sge;
                memset(cb->atapi.cdb, 0, 32);
                memcpy(cb->atapi.cdb, qc->cdb, qc->dev->cdb_len);

                if (ata_is_data(qc->tf.protocol)) {
                        if (qc->tf.flags & ATA_TFLAG_WRITE)
                                ctrl = PRB_CTRL_PACKET_WRITE;
                        else
                                ctrl = PRB_CTRL_PACKET_READ;
                }
        }

        prb->ctrl = cpu_to_le16(ctrl);
        ata_tf_to_fis(&qc->tf, qc->dev->link->pmp, 1, prb->fis);

        if (qc->flags & ATA_QCFLAG_DMAMAP)
                sil24_fill_sg(qc, sge);
}

static unsigned int sil24_qc_issue(struct ata_queued_cmd *qc)
{
        struct ata_port *ap = qc->ap;
        struct sil24_port_priv *pp = ap->private_data;
        void __iomem *port = ap->ioaddr.cmd_addr;
        unsigned int tag = sil24_tag(qc->tag);
        dma_addr_t paddr;
        void __iomem *activate;

        paddr = pp->cmd_block_dma + tag * sizeof(*pp->cmd_block);
        activate = port + PORT_CMD_ACTIVATE + tag * 8;

        writel((u32)paddr, activate);
        writel((u64)paddr >> 32, activate + 4);

        return 0;
}

static void sil24_irq_clear(struct ata_port *ap)
{
        /* unused */
}

static void sil24_pmp_attach(struct ata_port *ap)
{
        sil24_config_pmp(ap, 1);
        sil24_init_port(ap);
}

static void sil24_pmp_detach(struct ata_port *ap)
{
        sil24_init_port(ap);
        sil24_config_pmp(ap, 0);
}

static int sil24_pmp_softreset(struct ata_link *link, unsigned int *class,
                               unsigned long deadline)
{
        return sil24_do_softreset(link, class, link->pmp, deadline);
}

static int sil24_pmp_hardreset(struct ata_link *link, unsigned int *class,
                               unsigned long deadline)
{
        int rc;

        rc = sil24_init_port(link->ap);
        if (rc) {
                ata_link_printk(link, KERN_ERR,
                                "hardreset failed (port not ready)\n");
                return rc;
        }

        return sata_pmp_std_hardreset(link, class, deadline);
}

static void sil24_freeze(struct ata_port *ap)
{
        void __iomem *port = ap->ioaddr.cmd_addr;

        /* Port-wide IRQ mask in HOST_CTRL doesn't really work, clear
         * PORT_IRQ_ENABLE instead.
         */
        writel(0xffff, port + PORT_IRQ_ENABLE_CLR);
}

static void sil24_thaw(struct ata_port *ap)
{
        void __iomem *port = ap->ioaddr.cmd_addr;
        u32 tmp;

        /* clear IRQ */
        tmp = readl(port + PORT_IRQ_STAT);
        writel(tmp, port + PORT_IRQ_STAT);

        /* turn IRQ back on */
        writel(DEF_PORT_IRQ, port + PORT_IRQ_ENABLE_SET);
}

static void sil24_error_intr(struct ata_port *ap)
{
        void __iomem *port = ap->ioaddr.cmd_addr;
        struct sil24_port_priv *pp = ap->private_data;
        struct ata_queued_cmd *qc = NULL;
        struct ata_link *link;
        struct ata_eh_info *ehi;
        int abort = 0, freeze = 0;
        u32 irq_stat;

        /* on error, we need to clear IRQ explicitly */
        irq_stat = readl(port + PORT_IRQ_STAT);
        writel(irq_stat, port + PORT_IRQ_STAT);

        /* first, analyze and record host port events */
        link = &ap->link;
        ehi = &link->eh_info;
        ata_ehi_clear_desc(ehi);

        ata_ehi_push_desc(ehi, "irq_stat 0x%08x", irq_stat);

        if (irq_stat & PORT_IRQ_SDB_NOTIFY) {
                ata_ehi_push_desc(ehi, "SDB notify");
                sata_async_notification(ap);
        }

        if (irq_stat & (PORT_IRQ_PHYRDY_CHG | PORT_IRQ_DEV_XCHG)) {
                ata_ehi_hotplugged(ehi);
                ata_ehi_push_desc(ehi, "%s",
                                  irq_stat & PORT_IRQ_PHYRDY_CHG ?
                                  "PHY RDY changed" : "device exchanged");
                freeze = 1;
        }

        if (irq_stat & PORT_IRQ_UNK_FIS) {
                ehi->err_mask |= AC_ERR_HSM;
                ehi->action |= ATA_EH_SOFTRESET;
                ata_ehi_push_desc(ehi, "unknown FIS");
                freeze = 1;
        }

        /* deal with command error */
        if (irq_stat & PORT_IRQ_ERROR) {
                struct sil24_cerr_info *ci = NULL;
                unsigned int err_mask = 0, action = 0;
                u32 context, cerr;
                int pmp;

                abort = 1;

                /* DMA Context Switch Failure in Port Multiplier Mode
                 * errata.  If we have active commands to 3 or more
                 * devices, any error condition on active devices can
                 * corrupt DMA context switching.
                 */
                if (ap->nr_active_links >= 3) {
                        ehi->err_mask |= AC_ERR_OTHER;
                        ehi->action |= ATA_EH_HARDRESET;
                        ata_ehi_push_desc(ehi, "PMP DMA CS errata");
                        pp->do_port_rst = 1;
                        freeze = 1;
                }

                /* find out the offending link and qc */
                if (ap->nr_pmp_links) {
                        context = readl(port + PORT_CONTEXT);
                        pmp = (context >> 5) & 0xf;

                        if (pmp < ap->nr_pmp_links) {
                                link = &ap->pmp_link[pmp];
                                ehi = &link->eh_info;
                                qc = ata_qc_from_tag(ap, link->active_tag);

                                ata_ehi_clear_desc(ehi);
                                ata_ehi_push_desc(ehi, "irq_stat 0x%08x",
                                                  irq_stat);
                        } else {
                                err_mask |= AC_ERR_HSM;
                                action |= ATA_EH_HARDRESET;
                                freeze = 1;
                        }
                } else
                        qc = ata_qc_from_tag(ap, link->active_tag);

                /* analyze CMD_ERR */
                cerr = readl(port + PORT_CMD_ERR);
                if (cerr < ARRAY_SIZE(sil24_cerr_db))
                        ci = &sil24_cerr_db[cerr];

                if (ci && ci->desc) {
                        err_mask |= ci->err_mask;
                        action |= ci->action;
                        if (action & ATA_EH_RESET_MASK)
                                freeze = 1;
                        ata_ehi_push_desc(ehi, "%s", ci->desc);
                } else {
                        err_mask |= AC_ERR_OTHER;
                        action |= ATA_EH_SOFTRESET;
                        freeze = 1;
                        ata_ehi_push_desc(ehi, "unknown command error %d",
                                          cerr);
                }

                /* record error info */
                if (qc) {
                        sil24_read_tf(ap, qc->tag, &pp->tf);
                        qc->err_mask |= err_mask;
                } else
                        ehi->err_mask |= err_mask;

                ehi->action |= action;

                /* if PMP, resume */
                if (ap->nr_pmp_links)
                        writel(PORT_CS_PMP_RESUME, port + PORT_CTRL_STAT);
        }

        /* freeze or abort */
        if (freeze)
                ata_port_freeze(ap);
        else if (abort) {
                if (qc)
                        ata_link_abort(qc->dev->link);
                else
                        ata_port_abort(ap);
        }
}

static void sil24_finish_qc(struct ata_queued_cmd *qc)
{
        struct ata_port *ap = qc->ap;
        struct sil24_port_priv *pp = ap->private_data;

        if (qc->flags & ATA_QCFLAG_RESULT_TF)
                sil24_read_tf(ap, qc->tag, &pp->tf);
}

static inline void sil24_host_intr(struct ata_port *ap)
{
        void __iomem *port = ap->ioaddr.cmd_addr;
        u32 slot_stat, qc_active;
        int rc;

        /* If PCIX_IRQ_WOC, there's an inherent race window between
         * clearing IRQ pending status and reading PORT_SLOT_STAT
         * which may cause spurious interrupts afterwards.  This is
         * unavoidable and much better than losing interrupts which
         * happens if IRQ pending is cleared after reading
         * PORT_SLOT_STAT.
         */
        if (ap->flags & SIL24_FLAG_PCIX_IRQ_WOC)
                writel(PORT_IRQ_COMPLETE, port + PORT_IRQ_STAT);

        slot_stat = readl(port + PORT_SLOT_STAT);

        if (unlikely(slot_stat & HOST_SSTAT_ATTN)) {
                sil24_error_intr(ap);
                return;
        }

        qc_active = slot_stat & ~HOST_SSTAT_ATTN;
        rc = ata_qc_complete_multiple(ap, qc_active, sil24_finish_qc);
        if (rc > 0)
                return;
        if (rc < 0) {
                struct ata_eh_info *ehi = &ap->link.eh_info;
                ehi->err_mask |= AC_ERR_HSM;
                ehi->action |= ATA_EH_SOFTRESET;
                ata_port_freeze(ap);
                return;
        }

        /* spurious interrupts are expected if PCIX_IRQ_WOC */
        if (!(ap->flags & SIL24_FLAG_PCIX_IRQ_WOC) && ata_ratelimit())
                ata_port_printk(ap, KERN_INFO, "spurious interrupt "
                        "(slot_stat 0x%x active_tag %d sactive 0x%x)\n",
                        slot_stat, ap->link.active_tag, ap->link.sactive);
}

static irqreturn_t sil24_interrupt(int irq, void *dev_instance)
{
        struct ata_host *host = dev_instance;
        void __iomem *host_base = host->iomap[SIL24_HOST_BAR];
        unsigned handled = 0;
        u32 status;
        int i;

        status = readl(host_base + HOST_IRQ_STAT);

        if (status == 0xffffffff) {
                printk(KERN_ERR DRV_NAME ": IRQ status == 0xffffffff, "
                       "PCI fault or device removal?\n");
                goto out;
        }

        if (!(status & IRQ_STAT_4PORTS))
                goto out;

        spin_lock(&host->lock);

        for (i = 0; i < host->n_ports; i++)
                if (status & (1 << i)) {
                        struct ata_port *ap = host->ports[i];
                        if (ap && !(ap->flags & ATA_FLAG_DISABLED)) {
                                sil24_host_intr(ap);
                                handled++;
                        } else
                                printk(KERN_ERR DRV_NAME
                                       ": interrupt from disabled port %d\n", i);
                }

        spin_unlock(&host->lock);
 out:
        return IRQ_RETVAL(handled);
}

static void sil24_error_handler(struct ata_port *ap)
{
        struct sil24_port_priv *pp = ap->private_data;

        if (sil24_init_port(ap))
                ata_eh_freeze_port(ap);

        /* perform recovery */
        sata_pmp_do_eh(ap, ata_std_prereset, sil24_softreset, sil24_hardreset,
                       ata_std_postreset, sata_pmp_std_prereset,
                       sil24_pmp_softreset, sil24_pmp_hardreset,
                       sata_pmp_std_postreset);

        pp->do_port_rst = 0;
}

static void sil24_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) && sil24_init_port(ap))
                ata_eh_freeze_port(ap);
}

static int sil24_port_start(struct ata_port *ap)
{
        struct device *dev = ap->host->dev;
        struct sil24_port_priv *pp;
        union sil24_cmd_block *cb;
        size_t cb_size = sizeof(*cb) * SIL24_MAX_CMDS;
        dma_addr_t cb_dma;
        int rc;

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

        pp->tf.command = ATA_DRDY;

        cb = dmam_alloc_coherent(dev, cb_size, &cb_dma, GFP_KERNEL);
        if (!cb)
                return -ENOMEM;
        memset(cb, 0, cb_size);

        rc = ata_pad_alloc(ap, dev);
        if (rc)
                return rc;

        pp->cmd_block = cb;
        pp->cmd_block_dma = cb_dma;

        ap->private_data = pp;

        return 0;
}

static void sil24_init_controller(struct ata_host *host)
{
        void __iomem *host_base = host->iomap[SIL24_HOST_BAR];
        u32 tmp;
        int i;

        /* GPIO off */
        writel(0, host_base + HOST_FLASH_CMD);

        /* clear global reset & mask interrupts during initialization */
        writel(0, host_base + HOST_CTRL);

        /* init ports */
        for (i = 0; i < host->n_ports; i++) {
                struct ata_port *ap = host->ports[i];
                void __iomem *port = ap->ioaddr.cmd_addr;

                /* Initial PHY setting */
                writel(0x20c, port + PORT_PHY_CFG);

                /* Clear port RST */
                tmp = readl(port + PORT_CTRL_STAT);
                if (tmp & PORT_CS_PORT_RST) {
                        writel(PORT_CS_PORT_RST, port + PORT_CTRL_CLR);
                        tmp = ata_wait_register(port + PORT_CTRL_STAT,
                                                PORT_CS_PORT_RST,
                                                PORT_CS_PORT_RST, 10, 100);
                        if (tmp & PORT_CS_PORT_RST)
                                dev_printk(KERN_ERR, host->dev,
                                           "failed to clear port RST\n");
                }

                /* configure port */
                sil24_config_port(ap);
        }

        /* Turn on interrupts */
        writel(IRQ_STAT_4PORTS, host_base + HOST_CTRL);
}

static int sil24_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
{
        extern int __MARKER__sil24_cmd_block_is_sized_wrongly;
        static int printed_version;
        struct ata_port_info pi = sil24_port_info[ent->driver_data];
        const struct ata_port_info *ppi[] = { &pi, NULL };
        void __iomem * const *iomap;
        struct ata_host *host;
        int i, rc;
        u32 tmp;

        /* cause link error if sil24_cmd_block is sized wrongly */
        if (sizeof(union sil24_cmd_block) != PAGE_SIZE)
                __MARKER__sil24_cmd_block_is_sized_wrongly = 1;

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

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

        rc = pcim_iomap_regions(pdev,
                                (1 << SIL24_HOST_BAR) | (1 << SIL24_PORT_BAR),
                                DRV_NAME);
        if (rc)
                return rc;
        iomap = pcim_iomap_table(pdev);

        /* apply workaround for completion IRQ loss on PCI-X errata */
        if (pi.flags & SIL24_FLAG_PCIX_IRQ_WOC) {
                tmp = readl(iomap[SIL24_HOST_BAR] + HOST_CTRL);
                if (tmp & (HOST_CTRL_TRDY | HOST_CTRL_STOP | HOST_CTRL_DEVSEL))
                        dev_printk(KERN_INFO, &pdev->dev,
                                   "Applying completion IRQ loss on PCI-X "
                                   "errata fix\n");
                else
                        pi.flags &= ~SIL24_FLAG_PCIX_IRQ_WOC;
        }

        /* allocate and fill host */
        host = ata_host_alloc_pinfo(&pdev->dev, ppi,
                                    SIL24_FLAG2NPORTS(ppi[0]->flags));
        if (!host)
                return -ENOMEM;
        host->iomap = iomap;

        for (i = 0; i < host->n_ports; i++) {
                struct ata_port *ap = host->ports[i];
                size_t offset = ap->port_no * PORT_REGS_SIZE;
                void __iomem *port = iomap[SIL24_PORT_BAR] + offset;

                host->ports[i]->ioaddr.cmd_addr = port;
                host->ports[i]->ioaddr.scr_addr = port + PORT_SCONTROL;

                ata_port_pbar_desc(ap, SIL24_HOST_BAR, -1, "host");
                ata_port_pbar_desc(ap, SIL24_PORT_BAR, offset, "port");
        }

        /* configure and activate the device */
        if (!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;
                }
        }

        sil24_init_controller(host);

        pci_set_master(pdev);
        return ata_host_activate(host, pdev->irq, sil24_interrupt, IRQF_SHARED,
                                 &sil24_sht);
}

#ifdef CONFIG_PM
static int sil24_pci_device_resume(struct pci_dev *pdev)
{
        struct ata_host *host = dev_get_drvdata(&pdev->dev);
        void __iomem *host_base = host->iomap[SIL24_HOST_BAR];
        int rc;

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

        if (pdev->dev.power.power_state.event == PM_EVENT_SUSPEND)
                writel(HOST_CTRL_GLOBAL_RST, host_base + HOST_CTRL);

        sil24_init_controller(host);

        ata_host_resume(host);

        return 0;
}

static int sil24_port_resume(struct ata_port *ap)
{
        sil24_config_pmp(ap, ap->nr_pmp_links);
        return 0;
}
#endif

static int __init sil24_init(void)
{
        return pci_register_driver(&sil24_pci_driver);
}

static void __exit sil24_exit(void)
{
        pci_unregister_driver(&sil24_pci_driver);
}

MODULE_AUTHOR("Tejun Heo");
MODULE_DESCRIPTION("Silicon Image 3124/3132 SATA low-level driver");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, sil24_pci_tbl);

module_init(sil24_init);
module_exit(sil24_exit);