[PATCH] v4l: (963) em28xx IR fixup

[linux-2.6/sactl.git] / drivers / scsi / sata_mv.c

/*
 * sata_mv.c - Marvell SATA support
 *
 * Copyright 2005: EMC Corporation, all rights reserved. 
 *
 * Please ALWAYS copy linux-ide@vger.kernel.org on emails.
 *
 * 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; version 2 of the License.
 *
 * 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; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

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

#define DRV_NAME        "sata_mv"
#define DRV_VERSION     "0.25"

enum {
        /* BAR's are enumerated in terms of pci_resource_start() terms */
        MV_PRIMARY_BAR          = 0,    /* offset 0x10: memory space */
        MV_IO_BAR               = 2,    /* offset 0x18: IO space */
        MV_MISC_BAR             = 3,    /* offset 0x1c: FLASH, NVRAM, SRAM */

        MV_MAJOR_REG_AREA_SZ    = 0x10000,      /* 64KB */
        MV_MINOR_REG_AREA_SZ    = 0x2000,       /* 8KB */

        MV_PCI_REG_BASE         = 0,
        MV_IRQ_COAL_REG_BASE    = 0x18000,      /* 6xxx part only */
        MV_SATAHC0_REG_BASE     = 0x20000,

        MV_PCI_REG_SZ           = MV_MAJOR_REG_AREA_SZ,
        MV_SATAHC_REG_SZ        = MV_MAJOR_REG_AREA_SZ,
        MV_SATAHC_ARBTR_REG_SZ  = MV_MINOR_REG_AREA_SZ,         /* arbiter */
        MV_PORT_REG_SZ          = MV_MINOR_REG_AREA_SZ,

        MV_USE_Q_DEPTH          = ATA_DEF_QUEUE,

        MV_MAX_Q_DEPTH          = 32,
        MV_MAX_Q_DEPTH_MASK     = MV_MAX_Q_DEPTH - 1,

        /* CRQB needs alignment on a 1KB boundary. Size == 1KB
         * CRPB needs alignment on a 256B boundary. Size == 256B
         * SG count of 176 leads to MV_PORT_PRIV_DMA_SZ == 4KB
         * ePRD (SG) entries need alignment on a 16B boundary. Size == 16B
         */
        MV_CRQB_Q_SZ            = (32 * MV_MAX_Q_DEPTH),
        MV_CRPB_Q_SZ            = (8 * MV_MAX_Q_DEPTH),
        MV_MAX_SG_CT            = 176,
        MV_SG_TBL_SZ            = (16 * MV_MAX_SG_CT),
        MV_PORT_PRIV_DMA_SZ     = (MV_CRQB_Q_SZ + MV_CRPB_Q_SZ + MV_SG_TBL_SZ),

        /* Our DMA boundary is determined by an ePRD being unable to handle
         * anything larger than 64KB
         */
        MV_DMA_BOUNDARY         = 0xffffU,

        MV_PORTS_PER_HC         = 4,
        /* == (port / MV_PORTS_PER_HC) to determine HC from 0-7 port */
        MV_PORT_HC_SHIFT        = 2,
        /* == (port % MV_PORTS_PER_HC) to determine hard port from 0-7 port */
        MV_PORT_MASK            = 3,

        /* Host Flags */
        MV_FLAG_DUAL_HC         = (1 << 30),  /* two SATA Host Controllers */
        MV_FLAG_IRQ_COALESCE    = (1 << 29),  /* IRQ coalescing capability */
        MV_FLAG_GLBL_SFT_RST    = (1 << 28),  /* Global Soft Reset support */
        MV_COMMON_FLAGS         = (ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
                                   ATA_FLAG_SATA_RESET | ATA_FLAG_MMIO),
        MV_6XXX_FLAGS           = (MV_FLAG_IRQ_COALESCE | 
                                   MV_FLAG_GLBL_SFT_RST),

        chip_504x               = 0,
        chip_508x               = 1,
        chip_604x               = 2,
        chip_608x               = 3,

        CRQB_FLAG_READ          = (1 << 0),
        CRQB_TAG_SHIFT          = 1,
        CRQB_CMD_ADDR_SHIFT     = 8,
        CRQB_CMD_CS             = (0x2 << 11),
        CRQB_CMD_LAST           = (1 << 15),

        CRPB_FLAG_STATUS_SHIFT  = 8,

        EPRD_FLAG_END_OF_TBL    = (1 << 31),

        /* PCI interface registers */

        PCI_COMMAND_OFS         = 0xc00,

        PCI_MAIN_CMD_STS_OFS    = 0xd30,
        STOP_PCI_MASTER         = (1 << 2),
        PCI_MASTER_EMPTY        = (1 << 3),
        GLOB_SFT_RST            = (1 << 4),

        PCI_IRQ_CAUSE_OFS       = 0x1d58,
        PCI_IRQ_MASK_OFS        = 0x1d5c,
        PCI_UNMASK_ALL_IRQS     = 0x7fffff,     /* bits 22-0 */

        HC_MAIN_IRQ_CAUSE_OFS   = 0x1d60,
        HC_MAIN_IRQ_MASK_OFS    = 0x1d64,
        PORT0_ERR               = (1 << 0),     /* shift by port # */
        PORT0_DONE              = (1 << 1),     /* shift by port # */
        HC0_IRQ_PEND            = 0x1ff,        /* bits 0-8 = HC0's ports */
        HC_SHIFT                = 9,            /* bits 9-17 = HC1's ports */
        PCI_ERR                 = (1 << 18),
        TRAN_LO_DONE            = (1 << 19),    /* 6xxx: IRQ coalescing */
        TRAN_HI_DONE            = (1 << 20),    /* 6xxx: IRQ coalescing */
        PORTS_0_7_COAL_DONE     = (1 << 21),    /* 6xxx: IRQ coalescing */
        GPIO_INT                = (1 << 22),
        SELF_INT                = (1 << 23),
        TWSI_INT                = (1 << 24),
        HC_MAIN_RSVD            = (0x7f << 25), /* bits 31-25 */
        HC_MAIN_MASKED_IRQS     = (TRAN_LO_DONE | TRAN_HI_DONE | 
                                   PORTS_0_7_COAL_DONE | GPIO_INT | TWSI_INT |
                                   HC_MAIN_RSVD),

        /* SATAHC registers */
        HC_CFG_OFS              = 0,

        HC_IRQ_CAUSE_OFS        = 0x14,
        CRPB_DMA_DONE           = (1 << 0),     /* shift by port # */
        HC_IRQ_COAL             = (1 << 4),     /* IRQ coalescing */
        DEV_IRQ                 = (1 << 8),     /* shift by port # */

        /* Shadow block registers */
        SHD_BLK_OFS             = 0x100,
        SHD_CTL_AST_OFS         = 0x20,         /* ofs from SHD_BLK_OFS */

        /* SATA registers */
        SATA_STATUS_OFS         = 0x300,  /* ctrl, err regs follow status */
        SATA_ACTIVE_OFS         = 0x350,

        /* Port registers */
        EDMA_CFG_OFS            = 0,
        EDMA_CFG_Q_DEPTH        = 0,                    /* queueing disabled */
        EDMA_CFG_NCQ            = (1 << 5),
        EDMA_CFG_NCQ_GO_ON_ERR  = (1 << 14),            /* continue on error */
        EDMA_CFG_RD_BRST_EXT    = (1 << 11),            /* read burst 512B */
        EDMA_CFG_WR_BUFF_LEN    = (1 << 13),            /* write buffer 512B */

        EDMA_ERR_IRQ_CAUSE_OFS  = 0x8,
        EDMA_ERR_IRQ_MASK_OFS   = 0xc,
        EDMA_ERR_D_PAR          = (1 << 0),
        EDMA_ERR_PRD_PAR        = (1 << 1),
        EDMA_ERR_DEV            = (1 << 2),
        EDMA_ERR_DEV_DCON       = (1 << 3),
        EDMA_ERR_DEV_CON        = (1 << 4),
        EDMA_ERR_SERR           = (1 << 5),
        EDMA_ERR_SELF_DIS       = (1 << 7),
        EDMA_ERR_BIST_ASYNC     = (1 << 8),
        EDMA_ERR_CRBQ_PAR       = (1 << 9),
        EDMA_ERR_CRPB_PAR       = (1 << 10),
        EDMA_ERR_INTRL_PAR      = (1 << 11),
        EDMA_ERR_IORDY          = (1 << 12),
        EDMA_ERR_LNK_CTRL_RX    = (0xf << 13),
        EDMA_ERR_LNK_CTRL_RX_2  = (1 << 15),
        EDMA_ERR_LNK_DATA_RX    = (0xf << 17),
        EDMA_ERR_LNK_CTRL_TX    = (0x1f << 21),
        EDMA_ERR_LNK_DATA_TX    = (0x1f << 26),
        EDMA_ERR_TRANS_PROTO    = (1 << 31),
        EDMA_ERR_FATAL          = (EDMA_ERR_D_PAR | EDMA_ERR_PRD_PAR | 
                                   EDMA_ERR_DEV_DCON | EDMA_ERR_CRBQ_PAR |
                                   EDMA_ERR_CRPB_PAR | EDMA_ERR_INTRL_PAR |
                                   EDMA_ERR_IORDY | EDMA_ERR_LNK_CTRL_RX_2 | 
                                   EDMA_ERR_LNK_DATA_RX |
                                   EDMA_ERR_LNK_DATA_TX | 
                                   EDMA_ERR_TRANS_PROTO),

        EDMA_REQ_Q_BASE_HI_OFS  = 0x10,
        EDMA_REQ_Q_IN_PTR_OFS   = 0x14,         /* also contains BASE_LO */
        EDMA_REQ_Q_BASE_LO_MASK = 0xfffffc00U,

        EDMA_REQ_Q_OUT_PTR_OFS  = 0x18,
        EDMA_REQ_Q_PTR_SHIFT    = 5,

        EDMA_RSP_Q_BASE_HI_OFS  = 0x1c,
        EDMA_RSP_Q_IN_PTR_OFS   = 0x20,
        EDMA_RSP_Q_OUT_PTR_OFS  = 0x24,         /* also contains BASE_LO */
        EDMA_RSP_Q_BASE_LO_MASK = 0xffffff00U,
        EDMA_RSP_Q_PTR_SHIFT    = 3,

        EDMA_CMD_OFS            = 0x28,
        EDMA_EN                 = (1 << 0),
        EDMA_DS                 = (1 << 1),
        ATA_RST                 = (1 << 2),

        /* Host private flags (hp_flags) */
        MV_HP_FLAG_MSI          = (1 << 0),

        /* Port private flags (pp_flags) */
        MV_PP_FLAG_EDMA_EN      = (1 << 0),
        MV_PP_FLAG_EDMA_DS_ACT  = (1 << 1),
};

/* Command ReQuest Block: 32B */
struct mv_crqb {
        u32                     sg_addr;
        u32                     sg_addr_hi;
        u16                     ctrl_flags;
        u16                     ata_cmd[11];
};

/* Command ResPonse Block: 8B */
struct mv_crpb {
        u16                     id;
        u16                     flags;
        u32                     tmstmp;
};

/* EDMA Physical Region Descriptor (ePRD); A.K.A. SG */
struct mv_sg {
        u32                     addr;
        u32                     flags_size;
        u32                     addr_hi;
        u32                     reserved;
};

struct mv_port_priv {
        struct mv_crqb          *crqb;
        dma_addr_t              crqb_dma;
        struct mv_crpb          *crpb;
        dma_addr_t              crpb_dma;
        struct mv_sg            *sg_tbl;
        dma_addr_t              sg_tbl_dma;

        unsigned                req_producer;           /* cp of req_in_ptr */
        unsigned                rsp_consumer;           /* cp of rsp_out_ptr */
        u32                     pp_flags;
};

struct mv_host_priv {
        u32                     hp_flags;
};

static void mv_irq_clear(struct ata_port *ap);
static u32 mv_scr_read(struct ata_port *ap, unsigned int sc_reg_in);
static void mv_scr_write(struct ata_port *ap, unsigned int sc_reg_in, u32 val);
static void mv_phy_reset(struct ata_port *ap);
static void mv_host_stop(struct ata_host_set *host_set);
static int mv_port_start(struct ata_port *ap);
static void mv_port_stop(struct ata_port *ap);
static void mv_qc_prep(struct ata_queued_cmd *qc);
static int mv_qc_issue(struct ata_queued_cmd *qc);
static irqreturn_t mv_interrupt(int irq, void *dev_instance,
                                struct pt_regs *regs);
static void mv_eng_timeout(struct ata_port *ap);
static int mv_init_one(struct pci_dev *pdev, const struct pci_device_id *ent);

static struct scsi_host_template mv_sht = {
        .module                 = THIS_MODULE,
        .name                   = DRV_NAME,
        .ioctl                  = ata_scsi_ioctl,
        .queuecommand           = ata_scsi_queuecmd,
        .eh_strategy_handler    = ata_scsi_error,
        .can_queue              = MV_USE_Q_DEPTH,
        .this_id                = ATA_SHT_THIS_ID,
        .sg_tablesize           = MV_MAX_SG_CT,
        .max_sectors            = ATA_MAX_SECTORS,
        .cmd_per_lun            = ATA_SHT_CMD_PER_LUN,
        .emulated               = ATA_SHT_EMULATED,
        .use_clustering         = ATA_SHT_USE_CLUSTERING,
        .proc_name              = DRV_NAME,
        .dma_boundary           = MV_DMA_BOUNDARY,
        .slave_configure        = ata_scsi_slave_config,
        .bios_param             = ata_std_bios_param,
        .ordered_flush          = 1,
};

static const struct ata_port_operations mv_ops = {
        .port_disable           = ata_port_disable,

        .tf_load                = ata_tf_load,
        .tf_read                = ata_tf_read,
        .check_status           = ata_check_status,
        .exec_command           = ata_exec_command,
        .dev_select             = ata_std_dev_select,

        .phy_reset              = mv_phy_reset,

        .qc_prep                = mv_qc_prep,
        .qc_issue               = mv_qc_issue,

        .eng_timeout            = mv_eng_timeout,

        .irq_handler            = mv_interrupt,
        .irq_clear              = mv_irq_clear,

        .scr_read               = mv_scr_read,
        .scr_write              = mv_scr_write,

        .port_start             = mv_port_start,
        .port_stop              = mv_port_stop,
        .host_stop              = mv_host_stop,
};

static struct ata_port_info mv_port_info[] = {
        {  /* chip_504x */
                .sht            = &mv_sht,
                .host_flags     = MV_COMMON_FLAGS,
                .pio_mask       = 0x1f, /* pio0-4 */
                .udma_mask      = 0,    /* 0x7f (udma0-6 disabled for now) */
                .port_ops       = &mv_ops,
        },
        {  /* chip_508x */
                .sht            = &mv_sht,
                .host_flags     = (MV_COMMON_FLAGS | MV_FLAG_DUAL_HC),
                .pio_mask       = 0x1f, /* pio0-4 */
                .udma_mask      = 0,    /* 0x7f (udma0-6 disabled for now) */
                .port_ops       = &mv_ops,
        },
        {  /* chip_604x */
                .sht            = &mv_sht,
                .host_flags     = (MV_COMMON_FLAGS | MV_6XXX_FLAGS),
                .pio_mask       = 0x1f, /* pio0-4 */
                .udma_mask      = 0x7f, /* udma0-6 */
                .port_ops       = &mv_ops,
        },
        {  /* chip_608x */
                .sht            = &mv_sht,
                .host_flags     = (MV_COMMON_FLAGS | MV_6XXX_FLAGS | 
                                   MV_FLAG_DUAL_HC),
                .pio_mask       = 0x1f, /* pio0-4 */
                .udma_mask      = 0x7f, /* udma0-6 */
                .port_ops       = &mv_ops,
        },
};

static const struct pci_device_id mv_pci_tbl[] = {
        {PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x5040), 0, 0, chip_504x},
        {PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x5041), 0, 0, chip_504x},
        {PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x5080), 0, 0, chip_508x},
        {PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x5081), 0, 0, chip_508x},

        {PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x6040), 0, 0, chip_604x},
        {PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x6041), 0, 0, chip_604x},
        {PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x6080), 0, 0, chip_608x},
        {PCI_DEVICE(PCI_VENDOR_ID_MARVELL, 0x6081), 0, 0, chip_608x},

        {PCI_DEVICE(PCI_VENDOR_ID_ADAPTEC2, 0x0241), 0, 0, chip_604x},
        {}                      /* terminate list */
};

static struct pci_driver mv_pci_driver = {
        .name                   = DRV_NAME,
        .id_table               = mv_pci_tbl,
        .probe                  = mv_init_one,
        .remove                 = ata_pci_remove_one,
};

/*
 * Functions
 */

static inline void writelfl(unsigned long data, void __iomem *addr)
{
        writel(data, addr);
        (void) readl(addr);     /* flush to avoid PCI posted write */
}

static inline void __iomem *mv_hc_base(void __iomem *base, unsigned int hc)
{
        return (base + MV_SATAHC0_REG_BASE + (hc * MV_SATAHC_REG_SZ));
}

static inline void __iomem *mv_port_base(void __iomem *base, unsigned int port)
{
        return (mv_hc_base(base, port >> MV_PORT_HC_SHIFT) +
                MV_SATAHC_ARBTR_REG_SZ + 
                ((port & MV_PORT_MASK) * MV_PORT_REG_SZ));
}

static inline void __iomem *mv_ap_base(struct ata_port *ap)
{
        return mv_port_base(ap->host_set->mmio_base, ap->port_no);
}

static inline int mv_get_hc_count(unsigned long hp_flags)
{
        return ((hp_flags & MV_FLAG_DUAL_HC) ? 2 : 1);
}

static void mv_irq_clear(struct ata_port *ap)
{
}

/**
 *      mv_start_dma - Enable eDMA engine
 *      @base: port base address
 *      @pp: port private data
 *
 *      Verify the local cache of the eDMA state is accurate with an
 *      assert.
 *
 *      LOCKING:
 *      Inherited from caller.
 */
static void mv_start_dma(void __iomem *base, struct mv_port_priv *pp)
{
        if (!(MV_PP_FLAG_EDMA_EN & pp->pp_flags)) {
                writelfl(EDMA_EN, base + EDMA_CMD_OFS);
                pp->pp_flags |= MV_PP_FLAG_EDMA_EN;
        }
        assert(EDMA_EN & readl(base + EDMA_CMD_OFS));
}

/**
 *      mv_stop_dma - Disable eDMA engine
 *      @ap: ATA channel to manipulate
 *
 *      Verify the local cache of the eDMA state is accurate with an
 *      assert.
 *
 *      LOCKING:
 *      Inherited from caller.
 */
static void mv_stop_dma(struct ata_port *ap)
{
        void __iomem *port_mmio = mv_ap_base(ap);
        struct mv_port_priv *pp = ap->private_data;
        u32 reg;
        int i;

        if (MV_PP_FLAG_EDMA_EN & pp->pp_flags) {
                /* Disable EDMA if active.   The disable bit auto clears.
                 */
                writelfl(EDMA_DS, port_mmio + EDMA_CMD_OFS);
                pp->pp_flags &= ~MV_PP_FLAG_EDMA_EN;
        } else {
                assert(!(EDMA_EN & readl(port_mmio + EDMA_CMD_OFS)));
        }
        
        /* now properly wait for the eDMA to stop */
        for (i = 1000; i > 0; i--) {
                reg = readl(port_mmio + EDMA_CMD_OFS);
                if (!(EDMA_EN & reg)) {
                        break;
                }
                udelay(100);
        }

        if (EDMA_EN & reg) {
                printk(KERN_ERR "ata%u: Unable to stop eDMA\n", ap->id);
                /* FIXME: Consider doing a reset here to recover */
        }
}

#ifdef ATA_DEBUG
static void mv_dump_mem(void __iomem *start, unsigned bytes)
{
        int b, w;
        for (b = 0; b < bytes; ) {
                DPRINTK("%p: ", start + b);
                for (w = 0; b < bytes && w < 4; w++) {
                        printk("%08x ",readl(start + b));
                        b += sizeof(u32);
                }
                printk("\n");
        }
}
#endif

static void mv_dump_pci_cfg(struct pci_dev *pdev, unsigned bytes)
{
#ifdef ATA_DEBUG
        int b, w;
        u32 dw;
        for (b = 0; b < bytes; ) {
                DPRINTK("%02x: ", b);
                for (w = 0; b < bytes && w < 4; w++) {
                        (void) pci_read_config_dword(pdev,b,&dw);
                        printk("%08x ",dw);
                        b += sizeof(u32);
                }
                printk("\n");
        }
#endif
}
static void mv_dump_all_regs(void __iomem *mmio_base, int port,
                             struct pci_dev *pdev)
{
#ifdef ATA_DEBUG
        void __iomem *hc_base = mv_hc_base(mmio_base, 
                                           port >> MV_PORT_HC_SHIFT);
        void __iomem *port_base;
        int start_port, num_ports, p, start_hc, num_hcs, hc;

        if (0 > port) {
                start_hc = start_port = 0;
                num_ports = 8;          /* shld be benign for 4 port devs */
                num_hcs = 2;
        } else {
                start_hc = port >> MV_PORT_HC_SHIFT;
                start_port = port;
                num_ports = num_hcs = 1;
        }
        DPRINTK("All registers for port(s) %u-%u:\n", start_port, 
                num_ports > 1 ? num_ports - 1 : start_port);

        if (NULL != pdev) {
                DPRINTK("PCI config space regs:\n");
                mv_dump_pci_cfg(pdev, 0x68);
        }
        DPRINTK("PCI regs:\n");
        mv_dump_mem(mmio_base+0xc00, 0x3c);
        mv_dump_mem(mmio_base+0xd00, 0x34);
        mv_dump_mem(mmio_base+0xf00, 0x4);
        mv_dump_mem(mmio_base+0x1d00, 0x6c);
        for (hc = start_hc; hc < start_hc + num_hcs; hc++) {
                hc_base = mv_hc_base(mmio_base, port >> MV_PORT_HC_SHIFT);
                DPRINTK("HC regs (HC %i):\n", hc);
                mv_dump_mem(hc_base, 0x1c);
        }
        for (p = start_port; p < start_port + num_ports; p++) {
                port_base = mv_port_base(mmio_base, p);
                DPRINTK("EDMA regs (port %i):\n",p);
                mv_dump_mem(port_base, 0x54);
                DPRINTK("SATA regs (port %i):\n",p);
                mv_dump_mem(port_base+0x300, 0x60);
        }
#endif
}

static unsigned int mv_scr_offset(unsigned int sc_reg_in)
{
        unsigned int ofs;

        switch (sc_reg_in) {
        case SCR_STATUS:
        case SCR_CONTROL:
        case SCR_ERROR:
                ofs = SATA_STATUS_OFS + (sc_reg_in * sizeof(u32));
                break;
        case SCR_ACTIVE:
                ofs = SATA_ACTIVE_OFS;   /* active is not with the others */
                break;
        default:
                ofs = 0xffffffffU;
                break;
        }
        return ofs;
}

static u32 mv_scr_read(struct ata_port *ap, unsigned int sc_reg_in)
{
        unsigned int ofs = mv_scr_offset(sc_reg_in);

        if (0xffffffffU != ofs) {
                return readl(mv_ap_base(ap) + ofs);
        } else {
                return (u32) ofs;
        }
}

static void mv_scr_write(struct ata_port *ap, unsigned int sc_reg_in, u32 val)
{
        unsigned int ofs = mv_scr_offset(sc_reg_in);

        if (0xffffffffU != ofs) {
                writelfl(val, mv_ap_base(ap) + ofs);
        }
}

/**
 *      mv_global_soft_reset - Perform the 6xxx global soft reset
 *      @mmio_base: base address of the HBA
 *
 *      This routine only applies to 6xxx parts.
 *
 *      LOCKING:
 *      Inherited from caller.
 */
static int mv_global_soft_reset(void __iomem *mmio_base)
{
        void __iomem *reg = mmio_base + PCI_MAIN_CMD_STS_OFS;
        int i, rc = 0;
        u32 t;

        /* Following procedure defined in PCI "main command and status
         * register" table.
         */
        t = readl(reg);
        writel(t | STOP_PCI_MASTER, reg);

        for (i = 0; i < 1000; i++) {
                udelay(1);
                t = readl(reg);
                if (PCI_MASTER_EMPTY & t) {
                        break;
                }
        }
        if (!(PCI_MASTER_EMPTY & t)) {
                printk(KERN_ERR DRV_NAME ": PCI master won't flush\n");
                rc = 1;
                goto done;
        }

        /* set reset */
        i = 5;
        do {
                writel(t | GLOB_SFT_RST, reg);
                t = readl(reg);
                udelay(1);
        } while (!(GLOB_SFT_RST & t) && (i-- > 0));

        if (!(GLOB_SFT_RST & t)) {
                printk(KERN_ERR DRV_NAME ": can't set global reset\n");
                rc = 1;
                goto done;
        }

        /* clear reset and *reenable the PCI master* (not mentioned in spec) */
        i = 5;
        do {
                writel(t & ~(GLOB_SFT_RST | STOP_PCI_MASTER), reg);
                t = readl(reg);
                udelay(1);
        } while ((GLOB_SFT_RST & t) && (i-- > 0));

        if (GLOB_SFT_RST & t) {
                printk(KERN_ERR DRV_NAME ": can't clear global reset\n");
                rc = 1;
        }
done:
        return rc;
}

/**
 *      mv_host_stop - Host specific cleanup/stop routine.
 *      @host_set: host data structure
 *
 *      Disable ints, cleanup host memory, call general purpose
 *      host_stop.
 *
 *      LOCKING:
 *      Inherited from caller.
 */
static void mv_host_stop(struct ata_host_set *host_set)
{
        struct mv_host_priv *hpriv = host_set->private_data;
        struct pci_dev *pdev = to_pci_dev(host_set->dev);

        if (hpriv->hp_flags & MV_HP_FLAG_MSI) {
                pci_disable_msi(pdev);
        } else {
                pci_intx(pdev, 0);
        }
        kfree(hpriv);
        ata_host_stop(host_set);
}

static inline void mv_priv_free(struct mv_port_priv *pp, struct device *dev)
{
        dma_free_coherent(dev, MV_PORT_PRIV_DMA_SZ, pp->crpb, pp->crpb_dma);
}

/**
 *      mv_port_start - Port specific init/start routine.
 *      @ap: ATA channel to manipulate
 *
 *      Allocate and point to DMA memory, init port private memory,
 *      zero indices.
 *
 *      LOCKING:
 *      Inherited from caller.
 */
static int mv_port_start(struct ata_port *ap)
{
        struct device *dev = ap->host_set->dev;
        struct mv_port_priv *pp;
        void __iomem *port_mmio = mv_ap_base(ap);
        void *mem;
        dma_addr_t mem_dma;
        int rc = -ENOMEM;

        pp = kmalloc(sizeof(*pp), GFP_KERNEL);
        if (!pp)
                goto err_out;
        memset(pp, 0, sizeof(*pp));

        mem = dma_alloc_coherent(dev, MV_PORT_PRIV_DMA_SZ, &mem_dma, 
                                 GFP_KERNEL);
        if (!mem)
                goto err_out_pp;
        memset(mem, 0, MV_PORT_PRIV_DMA_SZ);

        rc = ata_pad_alloc(ap, dev);
        if (rc)
                goto err_out_priv;

        /* First item in chunk of DMA memory: 
         * 32-slot command request table (CRQB), 32 bytes each in size
         */
        pp->crqb = mem;
        pp->crqb_dma = mem_dma;
        mem += MV_CRQB_Q_SZ;
        mem_dma += MV_CRQB_Q_SZ;

        /* Second item: 
         * 32-slot command response table (CRPB), 8 bytes each in size
         */
        pp->crpb = mem;
        pp->crpb_dma = mem_dma;
        mem += MV_CRPB_Q_SZ;
        mem_dma += MV_CRPB_Q_SZ;

        /* Third item:
         * Table of scatter-gather descriptors (ePRD), 16 bytes each
         */
        pp->sg_tbl = mem;
        pp->sg_tbl_dma = mem_dma;

        writelfl(EDMA_CFG_Q_DEPTH | EDMA_CFG_RD_BRST_EXT | 
                 EDMA_CFG_WR_BUFF_LEN, port_mmio + EDMA_CFG_OFS);

        writel((pp->crqb_dma >> 16) >> 16, port_mmio + EDMA_REQ_Q_BASE_HI_OFS);
        writelfl(pp->crqb_dma & EDMA_REQ_Q_BASE_LO_MASK, 
                 port_mmio + EDMA_REQ_Q_IN_PTR_OFS);

        writelfl(0, port_mmio + EDMA_REQ_Q_OUT_PTR_OFS);
        writelfl(0, port_mmio + EDMA_RSP_Q_IN_PTR_OFS);

        writel((pp->crpb_dma >> 16) >> 16, port_mmio + EDMA_RSP_Q_BASE_HI_OFS);
        writelfl(pp->crpb_dma & EDMA_RSP_Q_BASE_LO_MASK, 
                 port_mmio + EDMA_RSP_Q_OUT_PTR_OFS);

        pp->req_producer = pp->rsp_consumer = 0;

        /* Don't turn on EDMA here...do it before DMA commands only.  Else
         * we'll be unable to send non-data, PIO, etc due to restricted access
         * to shadow regs.
         */
        ap->private_data = pp;
        return 0;

err_out_priv:
        mv_priv_free(pp, dev);
err_out_pp:
        kfree(pp);
err_out:
        return rc;
}

/**
 *      mv_port_stop - Port specific cleanup/stop routine.
 *      @ap: ATA channel to manipulate
 *
 *      Stop DMA, cleanup port memory.
 *
 *      LOCKING:
 *      This routine uses the host_set lock to protect the DMA stop.
 */
static void mv_port_stop(struct ata_port *ap)
{
        struct device *dev = ap->host_set->dev;
        struct mv_port_priv *pp = ap->private_data;
        unsigned long flags;

        spin_lock_irqsave(&ap->host_set->lock, flags);
        mv_stop_dma(ap);
        spin_unlock_irqrestore(&ap->host_set->lock, flags);

        ap->private_data = NULL;
        ata_pad_free(ap, dev);
        mv_priv_free(pp, dev);
        kfree(pp);
}

/**
 *      mv_fill_sg - Fill out the Marvell ePRD (scatter gather) entries
 *      @qc: queued command whose SG list to source from
 *
 *      Populate the SG list and mark the last entry.
 *
 *      LOCKING:
 *      Inherited from caller.
 */
static void mv_fill_sg(struct ata_queued_cmd *qc)
{
        struct mv_port_priv *pp = qc->ap->private_data;
        unsigned int i = 0;
        struct scatterlist *sg;

        ata_for_each_sg(sg, qc) {
                u32 sg_len;
                dma_addr_t addr;

                addr = sg_dma_address(sg);
                sg_len = sg_dma_len(sg);

                pp->sg_tbl[i].addr = cpu_to_le32(addr & 0xffffffff);
                pp->sg_tbl[i].addr_hi = cpu_to_le32((addr >> 16) >> 16);
                assert(0 == (sg_len & ~MV_DMA_BOUNDARY));
                pp->sg_tbl[i].flags_size = cpu_to_le32(sg_len);
                if (ata_sg_is_last(sg, qc))
                        pp->sg_tbl[i].flags_size |= cpu_to_le32(EPRD_FLAG_END_OF_TBL);

                i++;
        }
}

static inline unsigned mv_inc_q_index(unsigned *index)
{
        *index = (*index + 1) & MV_MAX_Q_DEPTH_MASK;
        return *index;
}

static inline void mv_crqb_pack_cmd(u16 *cmdw, u8 data, u8 addr, unsigned last)
{
        *cmdw = data | (addr << CRQB_CMD_ADDR_SHIFT) | CRQB_CMD_CS |
                (last ? CRQB_CMD_LAST : 0);
}

/**
 *      mv_qc_prep - Host specific command preparation.
 *      @qc: queued command to prepare
 *
 *      This routine simply redirects to the general purpose routine
 *      if command is not DMA.  Else, it handles prep of the CRQB
 *      (command request block), does some sanity checking, and calls
 *      the SG load routine.
 *
 *      LOCKING:
 *      Inherited from caller.
 */
static void mv_qc_prep(struct ata_queued_cmd *qc)
{
        struct ata_port *ap = qc->ap;
        struct mv_port_priv *pp = ap->private_data;
        u16 *cw;
        struct ata_taskfile *tf;
        u16 flags = 0;

        if (ATA_PROT_DMA != qc->tf.protocol) {
                return;
        }

        /* the req producer index should be the same as we remember it */
        assert(((readl(mv_ap_base(qc->ap) + EDMA_REQ_Q_IN_PTR_OFS) >> 
                 EDMA_REQ_Q_PTR_SHIFT) & MV_MAX_Q_DEPTH_MASK) ==
               pp->req_producer);

        /* Fill in command request block
         */
        if (!(qc->tf.flags & ATA_TFLAG_WRITE)) {
                flags |= CRQB_FLAG_READ;
        }
        assert(MV_MAX_Q_DEPTH > qc->tag);
        flags |= qc->tag << CRQB_TAG_SHIFT;

        pp->crqb[pp->req_producer].sg_addr = 
                cpu_to_le32(pp->sg_tbl_dma & 0xffffffff);
        pp->crqb[pp->req_producer].sg_addr_hi = 
                cpu_to_le32((pp->sg_tbl_dma >> 16) >> 16);
        pp->crqb[pp->req_producer].ctrl_flags = cpu_to_le16(flags);

        cw = &pp->crqb[pp->req_producer].ata_cmd[0];
        tf = &qc->tf;

        /* Sadly, the CRQB cannot accomodate all registers--there are
         * only 11 bytes...so we must pick and choose required
         * registers based on the command.  So, we drop feature and
         * hob_feature for [RW] DMA commands, but they are needed for
         * NCQ.  NCQ will drop hob_nsect.
         */
        switch (tf->command) {
        case ATA_CMD_READ:
        case ATA_CMD_READ_EXT:
        case ATA_CMD_WRITE:
        case ATA_CMD_WRITE_EXT:
                mv_crqb_pack_cmd(cw++, tf->hob_nsect, ATA_REG_NSECT, 0);
                break;
#ifdef LIBATA_NCQ               /* FIXME: remove this line when NCQ added */
        case ATA_CMD_FPDMA_READ:
        case ATA_CMD_FPDMA_WRITE:
                mv_crqb_pack_cmd(cw++, tf->hob_feature, ATA_REG_FEATURE, 0); 
                mv_crqb_pack_cmd(cw++, tf->feature, ATA_REG_FEATURE, 0);
                break;
#endif                          /* FIXME: remove this line when NCQ added */
        default:
                /* The only other commands EDMA supports in non-queued and
                 * non-NCQ mode are: [RW] STREAM DMA and W DMA FUA EXT, none
                 * of which are defined/used by Linux.  If we get here, this
                 * driver needs work.
                 *
                 * FIXME: modify libata to give qc_prep a return value and
                 * return error here.
                 */
                BUG_ON(tf->command);
                break;
        }
        mv_crqb_pack_cmd(cw++, tf->nsect, ATA_REG_NSECT, 0);
        mv_crqb_pack_cmd(cw++, tf->hob_lbal, ATA_REG_LBAL, 0);
        mv_crqb_pack_cmd(cw++, tf->lbal, ATA_REG_LBAL, 0);
        mv_crqb_pack_cmd(cw++, tf->hob_lbam, ATA_REG_LBAM, 0);
        mv_crqb_pack_cmd(cw++, tf->lbam, ATA_REG_LBAM, 0);
        mv_crqb_pack_cmd(cw++, tf->hob_lbah, ATA_REG_LBAH, 0);
        mv_crqb_pack_cmd(cw++, tf->lbah, ATA_REG_LBAH, 0);
        mv_crqb_pack_cmd(cw++, tf->device, ATA_REG_DEVICE, 0);
        mv_crqb_pack_cmd(cw++, tf->command, ATA_REG_CMD, 1);    /* last */

        if (!(qc->flags & ATA_QCFLAG_DMAMAP)) {
                return;
        }
        mv_fill_sg(qc);
}

/**
 *      mv_qc_issue - Initiate a command to the host
 *      @qc: queued command to start
 *
 *      This routine simply redirects to the general purpose routine
 *      if command is not DMA.  Else, it sanity checks our local
 *      caches of the request producer/consumer indices then enables
 *      DMA and bumps the request producer index.
 *
 *      LOCKING:
 *      Inherited from caller.
 */
static int mv_qc_issue(struct ata_queued_cmd *qc)
{
        void __iomem *port_mmio = mv_ap_base(qc->ap);
        struct mv_port_priv *pp = qc->ap->private_data;
        u32 in_ptr;

        if (ATA_PROT_DMA != qc->tf.protocol) {
                /* We're about to send a non-EDMA capable command to the
                 * port.  Turn off EDMA so there won't be problems accessing
                 * shadow block, etc registers.
                 */
                mv_stop_dma(qc->ap);
                return ata_qc_issue_prot(qc);
        }

        in_ptr = readl(port_mmio + EDMA_REQ_Q_IN_PTR_OFS);

        /* the req producer index should be the same as we remember it */
        assert(((in_ptr >> EDMA_REQ_Q_PTR_SHIFT) & MV_MAX_Q_DEPTH_MASK) ==
               pp->req_producer);
        /* until we do queuing, the queue should be empty at this point */
        assert(((in_ptr >> EDMA_REQ_Q_PTR_SHIFT) & MV_MAX_Q_DEPTH_MASK) ==
               ((readl(port_mmio + EDMA_REQ_Q_OUT_PTR_OFS) >> 
                 EDMA_REQ_Q_PTR_SHIFT) & MV_MAX_Q_DEPTH_MASK));

        mv_inc_q_index(&pp->req_producer);      /* now incr producer index */

        mv_start_dma(port_mmio, pp);

        /* and write the request in pointer to kick the EDMA to life */
        in_ptr &= EDMA_REQ_Q_BASE_LO_MASK;
        in_ptr |= pp->req_producer << EDMA_REQ_Q_PTR_SHIFT;
        writelfl(in_ptr, port_mmio + EDMA_REQ_Q_IN_PTR_OFS);

        return 0;
}

/**
 *      mv_get_crpb_status - get status from most recently completed cmd
 *      @ap: ATA channel to manipulate
 *
 *      This routine is for use when the port is in DMA mode, when it
 *      will be using the CRPB (command response block) method of
 *      returning command completion information.  We assert indices
 *      are good, grab status, and bump the response consumer index to
 *      prove that we're up to date.
 *
 *      LOCKING:
 *      Inherited from caller.
 */
static u8 mv_get_crpb_status(struct ata_port *ap)
{
        void __iomem *port_mmio = mv_ap_base(ap);
        struct mv_port_priv *pp = ap->private_data;
        u32 out_ptr;

        out_ptr = readl(port_mmio + EDMA_RSP_Q_OUT_PTR_OFS);

        /* the response consumer index should be the same as we remember it */
        assert(((out_ptr >> EDMA_RSP_Q_PTR_SHIFT) & MV_MAX_Q_DEPTH_MASK) == 
               pp->rsp_consumer);

        /* increment our consumer index... */
        pp->rsp_consumer = mv_inc_q_index(&pp->rsp_consumer);
        
        /* and, until we do NCQ, there should only be 1 CRPB waiting */
        assert(((readl(port_mmio + EDMA_RSP_Q_IN_PTR_OFS) >> 
                 EDMA_RSP_Q_PTR_SHIFT) & MV_MAX_Q_DEPTH_MASK) == 
               pp->rsp_consumer);

        /* write out our inc'd consumer index so EDMA knows we're caught up */
        out_ptr &= EDMA_RSP_Q_BASE_LO_MASK;
        out_ptr |= pp->rsp_consumer << EDMA_RSP_Q_PTR_SHIFT;
        writelfl(out_ptr, port_mmio + EDMA_RSP_Q_OUT_PTR_OFS);

        /* Return ATA status register for completed CRPB */
        return (pp->crpb[pp->rsp_consumer].flags >> CRPB_FLAG_STATUS_SHIFT);
}

/**
 *      mv_err_intr - Handle error interrupts on the port
 *      @ap: ATA channel to manipulate
 *
 *      In most cases, just clear the interrupt and move on.  However,
 *      some cases require an eDMA reset, which is done right before
 *      the COMRESET in mv_phy_reset().  The SERR case requires a
 *      clear of pending errors in the SATA SERROR register.  Finally,
 *      if the port disabled DMA, update our cached copy to match.
 *
 *      LOCKING:
 *      Inherited from caller.
 */
static void mv_err_intr(struct ata_port *ap)
{
        void __iomem *port_mmio = mv_ap_base(ap);
        u32 edma_err_cause, serr = 0;

        edma_err_cause = readl(port_mmio + EDMA_ERR_IRQ_CAUSE_OFS);

        if (EDMA_ERR_SERR & edma_err_cause) {
                serr = scr_read(ap, SCR_ERROR);
                scr_write_flush(ap, SCR_ERROR, serr);
        }
        if (EDMA_ERR_SELF_DIS & edma_err_cause) {
                struct mv_port_priv *pp = ap->private_data;
                pp->pp_flags &= ~MV_PP_FLAG_EDMA_EN;
        }
        DPRINTK(KERN_ERR "ata%u: port error; EDMA err cause: 0x%08x "
                "SERR: 0x%08x\n", ap->id, edma_err_cause, serr);

        /* Clear EDMA now that SERR cleanup done */
        writelfl(0, port_mmio + EDMA_ERR_IRQ_CAUSE_OFS);

        /* check for fatal here and recover if needed */
        if (EDMA_ERR_FATAL & edma_err_cause) {
                mv_phy_reset(ap);
        }
}

/**
 *      mv_host_intr - Handle all interrupts on the given host controller
 *      @host_set: host specific structure
 *      @relevant: port error bits relevant to this host controller
 *      @hc: which host controller we're to look at
 *
 *      Read then write clear the HC interrupt status then walk each
 *      port connected to the HC and see if it needs servicing.  Port
 *      success ints are reported in the HC interrupt status reg, the
 *      port error ints are reported in the higher level main
 *      interrupt status register and thus are passed in via the
 *      'relevant' argument.
 *
 *      LOCKING:
 *      Inherited from caller.
 */
static void mv_host_intr(struct ata_host_set *host_set, u32 relevant,
                         unsigned int hc)
{
        void __iomem *mmio = host_set->mmio_base;
        void __iomem *hc_mmio = mv_hc_base(mmio, hc);
        struct ata_port *ap;
        struct ata_queued_cmd *qc;
        u32 hc_irq_cause;
        int shift, port, port0, hard_port, handled;
        unsigned int err_mask;
        u8 ata_status = 0;

        if (hc == 0) {
                port0 = 0;
        } else {
                port0 = MV_PORTS_PER_HC;
        }

        /* we'll need the HC success int register in most cases */
        hc_irq_cause = readl(hc_mmio + HC_IRQ_CAUSE_OFS);
        if (hc_irq_cause) {
                writelfl(~hc_irq_cause, hc_mmio + HC_IRQ_CAUSE_OFS);
        }

        VPRINTK("ENTER, hc%u relevant=0x%08x HC IRQ cause=0x%08x\n",
                hc,relevant,hc_irq_cause);

        for (port = port0; port < port0 + MV_PORTS_PER_HC; port++) {
                ap = host_set->ports[port];
                hard_port = port & MV_PORT_MASK;        /* range 0-3 */
                handled = 0;    /* ensure ata_status is set if handled++ */

                if ((CRPB_DMA_DONE << hard_port) & hc_irq_cause) {
                        /* new CRPB on the queue; just one at a time until NCQ
                         */
                        ata_status = mv_get_crpb_status(ap);
                        handled++;
                } else if ((DEV_IRQ << hard_port) & hc_irq_cause) {
                        /* received ATA IRQ; read the status reg to clear INTRQ
                         */
                        ata_status = readb((void __iomem *)
                                           ap->ioaddr.status_addr);
                        handled++;
                }

                err_mask = ac_err_mask(ata_status);

                shift = port << 1;              /* (port * 2) */
                if (port >= MV_PORTS_PER_HC) {
                        shift++;        /* skip bit 8 in the HC Main IRQ reg */
                }
                if ((PORT0_ERR << shift) & relevant) {
                        mv_err_intr(ap);
                        err_mask |= AC_ERR_OTHER;
                        handled++;
                }
                
                if (handled && ap) {
                        qc = ata_qc_from_tag(ap, ap->active_tag);
                        if (NULL != qc) {
                                VPRINTK("port %u IRQ found for qc, "
                                        "ata_status 0x%x\n", port,ata_status);
                                /* mark qc status appropriately */
                                ata_qc_complete(qc, err_mask);
                        }
                }
        }
        VPRINTK("EXIT\n");
}

/**
 *      mv_interrupt - 
 *      @irq: unused
 *      @dev_instance: private data; in this case the host structure
 *      @regs: unused
 *
 *      Read the read only register to determine if any host
 *      controllers have pending interrupts.  If so, call lower level
 *      routine to handle.  Also check for PCI errors which are only
 *      reported here.
 *
 *      LOCKING: 
 *      This routine holds the host_set lock while processing pending
 *      interrupts.
 */
static irqreturn_t mv_interrupt(int irq, void *dev_instance,
                                struct pt_regs *regs)
{
        struct ata_host_set *host_set = dev_instance;
        unsigned int hc, handled = 0, n_hcs;
        void __iomem *mmio = host_set->mmio_base;
        u32 irq_stat;

        irq_stat = readl(mmio + HC_MAIN_IRQ_CAUSE_OFS);

        /* check the cases where we either have nothing pending or have read
         * a bogus register value which can indicate HW removal or PCI fault
         */
        if (!irq_stat || (0xffffffffU == irq_stat)) {
                return IRQ_NONE;
        }

        n_hcs = mv_get_hc_count(host_set->ports[0]->flags);
        spin_lock(&host_set->lock);

        for (hc = 0; hc < n_hcs; hc++) {
                u32 relevant = irq_stat & (HC0_IRQ_PEND << (hc * HC_SHIFT));
                if (relevant) {
                        mv_host_intr(host_set, relevant, hc);
                        handled++;
                }
        }
        if (PCI_ERR & irq_stat) {
                printk(KERN_ERR DRV_NAME ": PCI ERROR; PCI IRQ cause=0x%08x\n",
                       readl(mmio + PCI_IRQ_CAUSE_OFS));

                DPRINTK("All regs @ PCI error\n");
                mv_dump_all_regs(mmio, -1, to_pci_dev(host_set->dev));

                writelfl(0, mmio + PCI_IRQ_CAUSE_OFS);
                handled++;
        }
        spin_unlock(&host_set->lock);

        return IRQ_RETVAL(handled);
}

/**
 *      mv_phy_reset - Perform eDMA reset followed by COMRESET
 *      @ap: ATA channel to manipulate
 *
 *      Part of this is taken from __sata_phy_reset and modified to
 *      not sleep since this routine gets called from interrupt level.
 *
 *      LOCKING:
 *      Inherited from caller.  This is coded to safe to call at
 *      interrupt level, i.e. it does not sleep.
 */
static void mv_phy_reset(struct ata_port *ap)
{
        void __iomem *port_mmio = mv_ap_base(ap);
        struct ata_taskfile tf;
        struct ata_device *dev = &ap->device[0];
        unsigned long timeout;

        VPRINTK("ENTER, port %u, mmio 0x%p\n", ap->port_no, port_mmio);

        mv_stop_dma(ap);

        writelfl(ATA_RST, port_mmio + EDMA_CMD_OFS);
        udelay(25);             /* allow reset propagation */

        /* Spec never mentions clearing the bit.  Marvell's driver does
         * clear the bit, however.
         */
        writelfl(0, port_mmio + EDMA_CMD_OFS);

        VPRINTK("S-regs after ATA_RST: SStat 0x%08x SErr 0x%08x "
                "SCtrl 0x%08x\n", mv_scr_read(ap, SCR_STATUS),
                mv_scr_read(ap, SCR_ERROR), mv_scr_read(ap, SCR_CONTROL));

        /* proceed to init communications via the scr_control reg */
        scr_write_flush(ap, SCR_CONTROL, 0x301);
        mdelay(1);
        scr_write_flush(ap, SCR_CONTROL, 0x300);
        timeout = jiffies + (HZ * 1);
        do {
                mdelay(10);
                if ((scr_read(ap, SCR_STATUS) & 0xf) != 1)
                        break;
        } while (time_before(jiffies, timeout));

        VPRINTK("S-regs after PHY wake: SStat 0x%08x SErr 0x%08x "
                "SCtrl 0x%08x\n", mv_scr_read(ap, SCR_STATUS),
                mv_scr_read(ap, SCR_ERROR), mv_scr_read(ap, SCR_CONTROL));

        if (sata_dev_present(ap)) {
                ata_port_probe(ap);
        } else {
                printk(KERN_INFO "ata%u: no device found (phy stat %08x)\n",
                       ap->id, scr_read(ap, SCR_STATUS));
                ata_port_disable(ap);
                return;
        }
        ap->cbl = ATA_CBL_SATA;

        tf.lbah = readb((void __iomem *) ap->ioaddr.lbah_addr);
        tf.lbam = readb((void __iomem *) ap->ioaddr.lbam_addr);
        tf.lbal = readb((void __iomem *) ap->ioaddr.lbal_addr);
        tf.nsect = readb((void __iomem *) ap->ioaddr.nsect_addr);

        dev->class = ata_dev_classify(&tf);
        if (!ata_dev_present(dev)) {
                VPRINTK("Port disabled post-sig: No device present.\n");
                ata_port_disable(ap);
        }
        VPRINTK("EXIT\n");
}

/**
 *      mv_eng_timeout - Routine called by libata when SCSI times out I/O
 *      @ap: ATA channel to manipulate
 *
 *      Intent is to clear all pending error conditions, reset the
 *      chip/bus, fail the command, and move on.
 *
 *      LOCKING:
 *      This routine holds the host_set lock while failing the command.
 */
static void mv_eng_timeout(struct ata_port *ap)
{
        struct ata_queued_cmd *qc;
        unsigned long flags;

        printk(KERN_ERR "ata%u: Entering mv_eng_timeout\n",ap->id);
        DPRINTK("All regs @ start of eng_timeout\n");
        mv_dump_all_regs(ap->host_set->mmio_base, ap->port_no, 
                         to_pci_dev(ap->host_set->dev));

        qc = ata_qc_from_tag(ap, ap->active_tag);
        printk(KERN_ERR "mmio_base %p ap %p qc %p scsi_cmnd %p &cmnd %p\n",
               ap->host_set->mmio_base, ap, qc, qc->scsicmd, 
               &qc->scsicmd->cmnd);

        mv_err_intr(ap);
        mv_phy_reset(ap);

        if (!qc) {
                printk(KERN_ERR "ata%u: BUG: timeout without command\n",
                       ap->id);
        } else {
                /* hack alert!  We cannot use the supplied completion
                 * function from inside the ->eh_strategy_handler() thread.
                 * libata is the only user of ->eh_strategy_handler() in
                 * any kernel, so the default scsi_done() assumes it is
                 * not being called from the SCSI EH.
                 */
                spin_lock_irqsave(&ap->host_set->lock, flags);
                qc->scsidone = scsi_finish_command;
                ata_qc_complete(qc, AC_ERR_OTHER);
                spin_unlock_irqrestore(&ap->host_set->lock, flags);
        }
}

/**
 *      mv_port_init - Perform some early initialization on a single port.
 *      @port: libata data structure storing shadow register addresses
 *      @port_mmio: base address of the port
 *
 *      Initialize shadow register mmio addresses, clear outstanding
 *      interrupts on the port, and unmask interrupts for the future
 *      start of the port.
 *
 *      LOCKING:
 *      Inherited from caller.
 */
static void mv_port_init(struct ata_ioports *port,  void __iomem *port_mmio)
{
        unsigned long shd_base = (unsigned long) port_mmio + SHD_BLK_OFS;
        unsigned serr_ofs;

        /* PIO related setup 
         */
        port->data_addr = shd_base + (sizeof(u32) * ATA_REG_DATA);
        port->error_addr = 
                port->feature_addr = shd_base + (sizeof(u32) * ATA_REG_ERR);
        port->nsect_addr = shd_base + (sizeof(u32) * ATA_REG_NSECT);
        port->lbal_addr = shd_base + (sizeof(u32) * ATA_REG_LBAL);
        port->lbam_addr = shd_base + (sizeof(u32) * ATA_REG_LBAM);
        port->lbah_addr = shd_base + (sizeof(u32) * ATA_REG_LBAH);
        port->device_addr = shd_base + (sizeof(u32) * ATA_REG_DEVICE);
        port->status_addr = 
                port->command_addr = shd_base + (sizeof(u32) * ATA_REG_STATUS);
        /* special case: control/altstatus doesn't have ATA_REG_ address */
        port->altstatus_addr = port->ctl_addr = shd_base + SHD_CTL_AST_OFS;

        /* unused: */
        port->cmd_addr = port->bmdma_addr = port->scr_addr = 0;

        /* Clear any currently outstanding port interrupt conditions */
        serr_ofs = mv_scr_offset(SCR_ERROR);
        writelfl(readl(port_mmio + serr_ofs), port_mmio + serr_ofs);
        writelfl(0, port_mmio + EDMA_ERR_IRQ_CAUSE_OFS);

        /* unmask all EDMA error interrupts */
        writelfl(~0, port_mmio + EDMA_ERR_IRQ_MASK_OFS);

        VPRINTK("EDMA cfg=0x%08x EDMA IRQ err cause/mask=0x%08x/0x%08x\n", 
                readl(port_mmio + EDMA_CFG_OFS),
                readl(port_mmio + EDMA_ERR_IRQ_CAUSE_OFS),
                readl(port_mmio + EDMA_ERR_IRQ_MASK_OFS));
}

/**
 *      mv_host_init - Perform some early initialization of the host.
 *      @probe_ent: early data struct representing the host
 *
 *      If possible, do an early global reset of the host.  Then do
 *      our port init and clear/unmask all/relevant host interrupts.
 *
 *      LOCKING:
 *      Inherited from caller.
 */
static int mv_host_init(struct ata_probe_ent *probe_ent)
{
        int rc = 0, n_hc, port, hc;
        void __iomem *mmio = probe_ent->mmio_base;
        void __iomem *port_mmio;

        if ((MV_FLAG_GLBL_SFT_RST & probe_ent->host_flags) && 
            mv_global_soft_reset(probe_ent->mmio_base)) {
                rc = 1;
                goto done;
        }

        n_hc = mv_get_hc_count(probe_ent->host_flags);
        probe_ent->n_ports = MV_PORTS_PER_HC * n_hc;

        for (port = 0; port < probe_ent->n_ports; port++) {
                port_mmio = mv_port_base(mmio, port);
                mv_port_init(&probe_ent->port[port], port_mmio);
        }

        for (hc = 0; hc < n_hc; hc++) {
                void __iomem *hc_mmio = mv_hc_base(mmio, hc);

                VPRINTK("HC%i: HC config=0x%08x HC IRQ cause "
                        "(before clear)=0x%08x\n", hc,
                        readl(hc_mmio + HC_CFG_OFS),
                        readl(hc_mmio + HC_IRQ_CAUSE_OFS));

                /* Clear any currently outstanding hc interrupt conditions */
                writelfl(0, hc_mmio + HC_IRQ_CAUSE_OFS);
        }

        /* Clear any currently outstanding host interrupt conditions */
        writelfl(0, mmio + PCI_IRQ_CAUSE_OFS);

        /* and unmask interrupt generation for host regs */
        writelfl(PCI_UNMASK_ALL_IRQS, mmio + PCI_IRQ_MASK_OFS);
        writelfl(~HC_MAIN_MASKED_IRQS, mmio + HC_MAIN_IRQ_MASK_OFS);

        VPRINTK("HC MAIN IRQ cause/mask=0x%08x/0x%08x "
                "PCI int cause/mask=0x%08x/0x%08x\n", 
                readl(mmio + HC_MAIN_IRQ_CAUSE_OFS),
                readl(mmio + HC_MAIN_IRQ_MASK_OFS),
                readl(mmio + PCI_IRQ_CAUSE_OFS),
                readl(mmio + PCI_IRQ_MASK_OFS));
done:
        return rc;
}

/**
 *      mv_print_info - Dump key info to kernel log for perusal.
 *      @probe_ent: early data struct representing the host
 *
 *      FIXME: complete this.
 *
 *      LOCKING:
 *      Inherited from caller.
 */
static void mv_print_info(struct ata_probe_ent *probe_ent)
{
        struct pci_dev *pdev = to_pci_dev(probe_ent->dev);
        struct mv_host_priv *hpriv = probe_ent->private_data;
        u8 rev_id, scc;
        const char *scc_s;

        /* Use this to determine the HW stepping of the chip so we know
         * what errata to workaround
         */
        pci_read_config_byte(pdev, PCI_REVISION_ID, &rev_id);

        pci_read_config_byte(pdev, PCI_CLASS_DEVICE, &scc);
        if (scc == 0)
                scc_s = "SCSI";
        else if (scc == 0x01)
                scc_s = "RAID";
        else
                scc_s = "unknown";

        dev_printk(KERN_INFO, &pdev->dev,
               "%u slots %u ports %s mode IRQ via %s\n",
               (unsigned)MV_MAX_Q_DEPTH, probe_ent->n_ports, 
               scc_s, (MV_HP_FLAG_MSI & hpriv->hp_flags) ? "MSI" : "INTx");
}

/**
 *      mv_init_one - handle a positive probe of a Marvell host
 *      @pdev: PCI device found
 *      @ent: PCI device ID entry for the matched host
 *
 *      LOCKING:
 *      Inherited from caller.
 */
static int mv_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
{
        static int printed_version = 0;
        struct ata_probe_ent *probe_ent = NULL;
        struct mv_host_priv *hpriv;
        unsigned int board_idx = (unsigned int)ent->driver_data;
        void __iomem *mmio_base;
        int pci_dev_busy = 0, rc;

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

        rc = pci_enable_device(pdev);
        if (rc) {
                return rc;
        }

        rc = pci_request_regions(pdev, DRV_NAME);
        if (rc) {
                pci_dev_busy = 1;
                goto err_out;
        }

        probe_ent = kmalloc(sizeof(*probe_ent), GFP_KERNEL);
        if (probe_ent == NULL) {
                rc = -ENOMEM;
                goto err_out_regions;
        }

        memset(probe_ent, 0, sizeof(*probe_ent));
        probe_ent->dev = pci_dev_to_dev(pdev);
        INIT_LIST_HEAD(&probe_ent->node);

        mmio_base = pci_iomap(pdev, MV_PRIMARY_BAR, 0);
        if (mmio_base == NULL) {
                rc = -ENOMEM;
                goto err_out_free_ent;
        }

        hpriv = kmalloc(sizeof(*hpriv), GFP_KERNEL);
        if (!hpriv) {
                rc = -ENOMEM;
                goto err_out_iounmap;
        }
        memset(hpriv, 0, sizeof(*hpriv));

        probe_ent->sht = mv_port_info[board_idx].sht;
        probe_ent->host_flags = mv_port_info[board_idx].host_flags;
        probe_ent->pio_mask = mv_port_info[board_idx].pio_mask;
        probe_ent->udma_mask = mv_port_info[board_idx].udma_mask;
        probe_ent->port_ops = mv_port_info[board_idx].port_ops;

        probe_ent->irq = pdev->irq;
        probe_ent->irq_flags = SA_SHIRQ;
        probe_ent->mmio_base = mmio_base;
        probe_ent->private_data = hpriv;

        /* initialize adapter */
        rc = mv_host_init(probe_ent);
        if (rc) {
                goto err_out_hpriv;
        }

        /* Enable interrupts */
        if (pci_enable_msi(pdev) == 0) {
                hpriv->hp_flags |= MV_HP_FLAG_MSI;
        } else {
                pci_intx(pdev, 1);
        }

        mv_dump_pci_cfg(pdev, 0x68);
        mv_print_info(probe_ent);

        if (ata_device_add(probe_ent) == 0) {
                rc = -ENODEV;           /* No devices discovered */
                goto err_out_dev_add;
        }

        kfree(probe_ent);
        return 0;

err_out_dev_add:
        if (MV_HP_FLAG_MSI & hpriv->hp_flags) {
                pci_disable_msi(pdev);
        } else {
                pci_intx(pdev, 0);
        }
err_out_hpriv:
        kfree(hpriv);
err_out_iounmap:
        pci_iounmap(pdev, mmio_base);
err_out_free_ent:
        kfree(probe_ent);
err_out_regions:
        pci_release_regions(pdev);
err_out:
        if (!pci_dev_busy) {
                pci_disable_device(pdev);
        }

        return rc;
}

static int __init mv_init(void)
{
        return pci_module_init(&mv_pci_driver);
}

static void __exit mv_exit(void)
{
        pci_unregister_driver(&mv_pci_driver);
}

MODULE_AUTHOR("Brett Russ");
MODULE_DESCRIPTION("SCSI low-level driver for Marvell SATA controllers");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, mv_pci_tbl);
MODULE_VERSION(DRV_VERSION);

module_init(mv_init);
module_exit(mv_exit);