// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * drivers/ata/sata_fsl.c
 *
 * Freescale 3.0Gbps SATA device driver
 *
 * Author: Ashish Kalra <ashish.kalra@freescale.com>
 * Li Yang <leoli@freescale.com>
 *
 * Copyright (c) 2006-2007, 2011-2012 Freescale Semiconductor, Inc.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

#include <scsi/scsi_host.h>
#include <scsi/scsi_cmnd.h>
#include <linux/libata.h>
#include <asm/io.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>

static unsigned int intr_coalescing_count;
module_param(intr_coalescing_count, int, S_IRUGO);
MODULE_PARM_DESC(intr_coalescing_count,
                                 "INT coalescing count threshold (1..31)");

static unsigned int intr_coalescing_ticks;
module_param(intr_coalescing_ticks, int, S_IRUGO);
MODULE_PARM_DESC(intr_coalescing_ticks,
                                 "INT coalescing timer threshold in AHB ticks");
/* Controller information */
enum {
        SATA_FSL_QUEUE_DEPTH    = 16,
        SATA_FSL_MAX_PRD        = 63,
        SATA_FSL_MAX_PRD_USABLE = SATA_FSL_MAX_PRD - 1,
        SATA_FSL_MAX_PRD_DIRECT = 16,   /* Direct PRDT entries */

        SATA_FSL_HOST_FLAGS     = (ATA_FLAG_SATA | ATA_FLAG_PIO_DMA |
                                   ATA_FLAG_PMP | ATA_FLAG_NCQ |
                                   ATA_FLAG_AN | ATA_FLAG_NO_LOG_PAGE),

        SATA_FSL_MAX_CMDS       = SATA_FSL_QUEUE_DEPTH,
        SATA_FSL_CMD_HDR_SIZE   = 16,   /* 4 DWORDS */
        SATA_FSL_CMD_SLOT_SIZE  = (SATA_FSL_MAX_CMDS * SATA_FSL_CMD_HDR_SIZE),

        /*
         * SATA-FSL host controller supports a max. of (15+1) direct PRDEs, and
         * chained indirect PRDEs up to a max count of 63.
         * We are allocating an array of 63 PRDEs contiguously, but PRDE#15 will
         * be setup as an indirect descriptor, pointing to it's next
         * (contiguous) PRDE. Though chained indirect PRDE arrays are
         * supported,it will be more efficient to use a direct PRDT and
         * a single chain/link to indirect PRDE array/PRDT.
         */

        SATA_FSL_CMD_DESC_CFIS_SZ       = 32,
        SATA_FSL_CMD_DESC_SFIS_SZ       = 32,
        SATA_FSL_CMD_DESC_ACMD_SZ       = 16,
        SATA_FSL_CMD_DESC_RSRVD         = 16,

        SATA_FSL_CMD_DESC_SIZE  = (SATA_FSL_CMD_DESC_CFIS_SZ +
                                 SATA_FSL_CMD_DESC_SFIS_SZ +
                                 SATA_FSL_CMD_DESC_ACMD_SZ +
                                 SATA_FSL_CMD_DESC_RSRVD +
                                 SATA_FSL_MAX_PRD * 16),

        SATA_FSL_CMD_DESC_OFFSET_TO_PRDT        =
                                (SATA_FSL_CMD_DESC_CFIS_SZ +
                                 SATA_FSL_CMD_DESC_SFIS_SZ +
                                 SATA_FSL_CMD_DESC_ACMD_SZ +
                                 SATA_FSL_CMD_DESC_RSRVD),

        SATA_FSL_CMD_DESC_AR_SZ = (SATA_FSL_CMD_DESC_SIZE * SATA_FSL_MAX_CMDS),
        SATA_FSL_PORT_PRIV_DMA_SZ = (SATA_FSL_CMD_SLOT_SIZE +
                                        SATA_FSL_CMD_DESC_AR_SZ),

        /*
         * MPC8315 has two SATA controllers, SATA1 & SATA2
         * (one port per controller)
         * MPC837x has 2/4 controllers, one port per controller
         */

        SATA_FSL_MAX_PORTS      = 1,

        SATA_FSL_IRQ_FLAG       = IRQF_SHARED,
};

/*
 * Interrupt Coalescing Control Register bitdefs  */
enum {
        ICC_MIN_INT_COUNT_THRESHOLD     = 1,
        ICC_MAX_INT_COUNT_THRESHOLD     = ((1 << 5) - 1),
        ICC_MIN_INT_TICKS_THRESHOLD     = 0,
        ICC_MAX_INT_TICKS_THRESHOLD     = ((1 << 19) - 1),
        ICC_SAFE_INT_TICKS              = 1,
};

/*
* Host Controller command register set - per port
*/
enum {
        CQ = 0,
        CA = 8,
        CC = 0x10,
        CE = 0x18,
        DE = 0x20,
        CHBA = 0x24,
        HSTATUS = 0x28,
        HCONTROL = 0x2C,
        CQPMP = 0x30,
        SIGNATURE = 0x34,
        ICC = 0x38,

        /*
         * Host Status Register (HStatus) bitdefs
         */
        ONLINE = (1 << 31),
        GOING_OFFLINE = (1 << 30),
        BIST_ERR = (1 << 29),
        CLEAR_ERROR = (1 << 27),

        FATAL_ERR_HC_MASTER_ERR = (1 << 18),
        FATAL_ERR_PARITY_ERR_TX = (1 << 17),
        FATAL_ERR_PARITY_ERR_RX = (1 << 16),
        FATAL_ERR_DATA_UNDERRUN = (1 << 13),
        FATAL_ERR_DATA_OVERRUN = (1 << 12),
        FATAL_ERR_CRC_ERR_TX = (1 << 11),
        FATAL_ERR_CRC_ERR_RX = (1 << 10),
        FATAL_ERR_FIFO_OVRFL_TX = (1 << 9),
        FATAL_ERR_FIFO_OVRFL_RX = (1 << 8),

        FATAL_ERROR_DECODE = FATAL_ERR_HC_MASTER_ERR |
            FATAL_ERR_PARITY_ERR_TX |
            FATAL_ERR_PARITY_ERR_RX |
            FATAL_ERR_DATA_UNDERRUN |
            FATAL_ERR_DATA_OVERRUN |
            FATAL_ERR_CRC_ERR_TX |
            FATAL_ERR_CRC_ERR_RX |
            FATAL_ERR_FIFO_OVRFL_TX | FATAL_ERR_FIFO_OVRFL_RX,

        INT_ON_DATA_LENGTH_MISMATCH = (1 << 12),
        INT_ON_FATAL_ERR = (1 << 5),
        INT_ON_PHYRDY_CHG = (1 << 4),

        INT_ON_SIGNATURE_UPDATE = (1 << 3),
        INT_ON_SNOTIFY_UPDATE = (1 << 2),
        INT_ON_SINGL_DEVICE_ERR = (1 << 1),
        INT_ON_CMD_COMPLETE = 1,

        INT_ON_ERROR = INT_ON_FATAL_ERR | INT_ON_SNOTIFY_UPDATE |
            INT_ON_PHYRDY_CHG | INT_ON_SINGL_DEVICE_ERR,

        /*
         * Host Control Register (HControl) bitdefs
         */
        HCONTROL_ONLINE_PHY_RST = (1 << 31),
        HCONTROL_FORCE_OFFLINE = (1 << 30),
        HCONTROL_LEGACY = (1 << 28),
        HCONTROL_PARITY_PROT_MOD = (1 << 14),
        HCONTROL_DPATH_PARITY = (1 << 12),
        HCONTROL_SNOOP_ENABLE = (1 << 10),
        HCONTROL_PMP_ATTACHED = (1 << 9),
        HCONTROL_COPYOUT_STATFIS = (1 << 8),
        IE_ON_FATAL_ERR = (1 << 5),
        IE_ON_PHYRDY_CHG = (1 << 4),
        IE_ON_SIGNATURE_UPDATE = (1 << 3),
        IE_ON_SNOTIFY_UPDATE = (1 << 2),
        IE_ON_SINGL_DEVICE_ERR = (1 << 1),
        IE_ON_CMD_COMPLETE = 1,

        DEFAULT_PORT_IRQ_ENABLE_MASK = IE_ON_FATAL_ERR | IE_ON_PHYRDY_CHG |
            IE_ON_SIGNATURE_UPDATE | IE_ON_SNOTIFY_UPDATE |
            IE_ON_SINGL_DEVICE_ERR | IE_ON_CMD_COMPLETE,

        EXT_INDIRECT_SEG_PRD_FLAG = (1 << 31),
        DATA_SNOOP_ENABLE_V1 = (1 << 22),
        DATA_SNOOP_ENABLE_V2 = (1 << 28),
};

/*
 * SATA Superset Registers
 */
enum {
        SSTATUS = 0,
        SERROR = 4,
        SCONTROL = 8,
        SNOTIFY = 0xC,
};

/*
 * Control Status Register Set
 */
enum {
        TRANSCFG = 0,
        TRANSSTATUS = 4,
        LINKCFG = 8,
        LINKCFG1 = 0xC,
        LINKCFG2 = 0x10,
        LINKSTATUS = 0x14,
        LINKSTATUS1 = 0x18,
        PHYCTRLCFG = 0x1C,
        COMMANDSTAT = 0x20,
};

/* TRANSCFG (transport-layer) configuration control */
enum {
        TRANSCFG_RX_WATER_MARK = (1 << 4),
};

/* PHY (link-layer) configuration control */
enum {
        PHY_BIST_ENABLE = 0x01,
};

/*
 * Command Header Table entry, i.e, command slot
 * 4 Dwords per command slot, command header size ==  64 Dwords.
 */
struct cmdhdr_tbl_entry {
        u32 cda;
        u32 prde_fis_len;
        u32 ttl;
        u32 desc_info;
};

/*
 * Description information bitdefs
 */
enum {
        CMD_DESC_RES = (1 << 11),
        VENDOR_SPECIFIC_BIST = (1 << 10),
        CMD_DESC_SNOOP_ENABLE = (1 << 9),
        FPDMA_QUEUED_CMD = (1 << 8),
        SRST_CMD = (1 << 7),
        BIST = (1 << 6),
        ATAPI_CMD = (1 << 5),
};

/*
 * Command Descriptor
 */
struct command_desc {
        u8 cfis[8 * 4];
        u8 sfis[8 * 4];
        u8 acmd[4 * 4];
        u8 fill[4 * 4];
        u32 prdt[SATA_FSL_MAX_PRD_DIRECT * 4];
        u32 prdt_indirect[(SATA_FSL_MAX_PRD - SATA_FSL_MAX_PRD_DIRECT) * 4];
};

/*
 * Physical region table descriptor(PRD)
 */

struct prde {
        u32 dba;
        u8 fill[2 * 4];
        u32 ddc_and_ext;
};

/*
 * ata_port private data
 * This is our per-port instance data.
 */
struct sata_fsl_port_priv {
        struct cmdhdr_tbl_entry *cmdslot;
        dma_addr_t cmdslot_paddr;
        struct command_desc *cmdentry;
        dma_addr_t cmdentry_paddr;
};

/*
 * ata_port->host_set private data
 */
struct sata_fsl_host_priv {
        void __iomem *hcr_base;
        void __iomem *ssr_base;
        void __iomem *csr_base;
        int irq;
        int data_snoop;
        struct device_attribute intr_coalescing;
        struct device_attribute rx_watermark;
};

static void fsl_sata_set_irq_coalescing(struct ata_host *host,
                unsigned int count, unsigned int ticks)
{
        struct sata_fsl_host_priv *host_priv = host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        unsigned long flags;

        if (count > ICC_MAX_INT_COUNT_THRESHOLD)
                count = ICC_MAX_INT_COUNT_THRESHOLD;
        else if (count < ICC_MIN_INT_COUNT_THRESHOLD)
                count = ICC_MIN_INT_COUNT_THRESHOLD;

        if (ticks > ICC_MAX_INT_TICKS_THRESHOLD)
                ticks = ICC_MAX_INT_TICKS_THRESHOLD;
        else if ((ICC_MIN_INT_TICKS_THRESHOLD == ticks) &&
                        (count > ICC_MIN_INT_COUNT_THRESHOLD))
                ticks = ICC_SAFE_INT_TICKS;

        spin_lock_irqsave(&host->lock, flags);
        iowrite32((count << 24 | ticks), hcr_base + ICC);

        intr_coalescing_count = count;
        intr_coalescing_ticks = ticks;
        spin_unlock_irqrestore(&host->lock, flags);

        DPRINTK("interrupt coalescing, count = 0x%x, ticks = %x\n",
                        intr_coalescing_count, intr_coalescing_ticks);
        DPRINTK("ICC register status: (hcr base: 0x%x) = 0x%x\n",
                        hcr_base, ioread32(hcr_base + ICC));
}

static ssize_t fsl_sata_intr_coalescing_show(struct device *dev,
                struct device_attribute *attr, char *buf)
{
        return sprintf(buf, "%d %d\n",
                        intr_coalescing_count, intr_coalescing_ticks);
}

static ssize_t fsl_sata_intr_coalescing_store(struct device *dev,
                struct device_attribute *attr,
                const char *buf, size_t count)
{
        unsigned int coalescing_count,  coalescing_ticks;

        if (sscanf(buf, "%d%d",
                                &coalescing_count,
                                &coalescing_ticks) != 2) {
                printk(KERN_ERR "fsl-sata: wrong parameter format.\n");
                return -EINVAL;
        }

        fsl_sata_set_irq_coalescing(dev_get_drvdata(dev),
                        coalescing_count, coalescing_ticks);

        return strlen(buf);
}

static ssize_t fsl_sata_rx_watermark_show(struct device *dev,
                struct device_attribute *attr, char *buf)
{
        unsigned int rx_watermark;
        unsigned long flags;
        struct ata_host *host = dev_get_drvdata(dev);
        struct sata_fsl_host_priv *host_priv = host->private_data;
        void __iomem *csr_base = host_priv->csr_base;

        spin_lock_irqsave(&host->lock, flags);
        rx_watermark = ioread32(csr_base + TRANSCFG);
        rx_watermark &= 0x1f;

        spin_unlock_irqrestore(&host->lock, flags);
        return sprintf(buf, "%d\n", rx_watermark);
}

static ssize_t fsl_sata_rx_watermark_store(struct device *dev,
                struct device_attribute *attr,
                const char *buf, size_t count)
{
        unsigned int rx_watermark;
        unsigned long flags;
        struct ata_host *host = dev_get_drvdata(dev);
        struct sata_fsl_host_priv *host_priv = host->private_data;
        void __iomem *csr_base = host_priv->csr_base;
        u32 temp;

        if (sscanf(buf, "%d", &rx_watermark) != 1) {
                printk(KERN_ERR "fsl-sata: wrong parameter format.\n");
                return -EINVAL;
        }

        spin_lock_irqsave(&host->lock, flags);
        temp = ioread32(csr_base + TRANSCFG);
        temp &= 0xffffffe0;
        iowrite32(temp | rx_watermark, csr_base + TRANSCFG);

        spin_unlock_irqrestore(&host->lock, flags);
        return strlen(buf);
}

static inline unsigned int sata_fsl_tag(unsigned int tag,
                                        void __iomem *hcr_base)
{
        /* We let libATA core do actual (queue) tag allocation */

        if (unlikely(tag >= SATA_FSL_QUEUE_DEPTH)) {
                DPRINTK("tag %d invalid : out of range\n", tag);
                return 0;
        }

        if (unlikely((ioread32(hcr_base + CQ)) & (1 << tag))) {
                DPRINTK("tag %d invalid : in use!!\n", tag);
                return 0;
        }

        return tag;
}

static void sata_fsl_setup_cmd_hdr_entry(struct sata_fsl_port_priv *pp,
                                         unsigned int tag, u32 desc_info,
                                         u32 data_xfer_len, u8 num_prde,
                                         u8 fis_len)
{
        dma_addr_t cmd_descriptor_address;

        cmd_descriptor_address = pp->cmdentry_paddr +
            tag * SATA_FSL_CMD_DESC_SIZE;

        /* NOTE: both data_xfer_len & fis_len are Dword counts */

        pp->cmdslot[tag].cda = cpu_to_le32(cmd_descriptor_address);
        pp->cmdslot[tag].prde_fis_len =
            cpu_to_le32((num_prde << 16) | (fis_len << 2));
        pp->cmdslot[tag].ttl = cpu_to_le32(data_xfer_len & ~0x03);
        pp->cmdslot[tag].desc_info = cpu_to_le32(desc_info | (tag & 0x1F));

        VPRINTK("cda=0x%x, prde_fis_len=0x%x, ttl=0x%x, di=0x%x\n",
                pp->cmdslot[tag].cda,
                pp->cmdslot[tag].prde_fis_len,
                pp->cmdslot[tag].ttl, pp->cmdslot[tag].desc_info);

}

static unsigned int sata_fsl_fill_sg(struct ata_queued_cmd *qc, void *cmd_desc,
                                     u32 *ttl, dma_addr_t cmd_desc_paddr,
                                     int data_snoop)
{
        struct scatterlist *sg;
        unsigned int num_prde = 0;
        u32 ttl_dwords = 0;

        /*
         * NOTE : direct & indirect prdt's are contiguously allocated
         */
        struct prde *prd = (struct prde *)&((struct command_desc *)
                                            cmd_desc)->prdt;

        struct prde *prd_ptr_to_indirect_ext = NULL;
        unsigned indirect_ext_segment_sz = 0;
        dma_addr_t indirect_ext_segment_paddr;
        unsigned int si;

        VPRINTK("SATA FSL : cd = 0x%p, prd = 0x%p\n", cmd_desc, prd);

        indirect_ext_segment_paddr = cmd_desc_paddr +
            SATA_FSL_CMD_DESC_OFFSET_TO_PRDT + SATA_FSL_MAX_PRD_DIRECT * 16;

        for_each_sg(qc->sg, sg, qc->n_elem, si) {
                dma_addr_t sg_addr = sg_dma_address(sg);
                u32 sg_len = sg_dma_len(sg);

                VPRINTK("SATA FSL : fill_sg, sg_addr = 0x%llx, sg_len = %d\n",
                        (unsigned long long)sg_addr, sg_len);

                /* warn if each s/g element is not dword aligned */
                if (unlikely(sg_addr & 0x03))
                        ata_port_err(qc->ap, "s/g addr unaligned : 0x%llx\n",
                                     (unsigned long long)sg_addr);
                if (unlikely(sg_len & 0x03))
                        ata_port_err(qc->ap, "s/g len unaligned : 0x%x\n",
                                     sg_len);

                if (num_prde == (SATA_FSL_MAX_PRD_DIRECT - 1) &&
                    sg_next(sg) != NULL) {
                        VPRINTK("setting indirect prde\n");
                        prd_ptr_to_indirect_ext = prd;
                        prd->dba = cpu_to_le32(indirect_ext_segment_paddr);
                        indirect_ext_segment_sz = 0;
                        ++prd;
                        ++num_prde;
                }

                ttl_dwords += sg_len;
                prd->dba = cpu_to_le32(sg_addr);
                prd->ddc_and_ext = cpu_to_le32(data_snoop | (sg_len & ~0x03));

                VPRINTK("sg_fill, ttl=%d, dba=0x%x, ddc=0x%x\n",
                        ttl_dwords, prd->dba, prd->ddc_and_ext);

                ++num_prde;
                ++prd;
                if (prd_ptr_to_indirect_ext)
                        indirect_ext_segment_sz += sg_len;
        }

        if (prd_ptr_to_indirect_ext) {
                /* set indirect extension flag along with indirect ext. size */
                prd_ptr_to_indirect_ext->ddc_and_ext =
                    cpu_to_le32((EXT_INDIRECT_SEG_PRD_FLAG |
                                 data_snoop |
                                 (indirect_ext_segment_sz & ~0x03)));
        }

        *ttl = ttl_dwords;
        return num_prde;
}

static enum ata_completion_errors sata_fsl_qc_prep(struct ata_queued_cmd *qc)
{
        struct ata_port *ap = qc->ap;
        struct sata_fsl_port_priv *pp = ap->private_data;
        struct sata_fsl_host_priv *host_priv = ap->host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        unsigned int tag = sata_fsl_tag(qc->hw_tag, hcr_base);
        struct command_desc *cd;
        u32 desc_info = CMD_DESC_RES | CMD_DESC_SNOOP_ENABLE;
        u32 num_prde = 0;
        u32 ttl_dwords = 0;
        dma_addr_t cd_paddr;

        cd = (struct command_desc *)pp->cmdentry + tag;
        cd_paddr = pp->cmdentry_paddr + tag * SATA_FSL_CMD_DESC_SIZE;

        ata_tf_to_fis(&qc->tf, qc->dev->link->pmp, 1, (u8 *) &cd->cfis);

        VPRINTK("Dumping cfis : 0x%x, 0x%x, 0x%x\n",
                cd->cfis[0], cd->cfis[1], cd->cfis[2]);

        if (qc->tf.protocol == ATA_PROT_NCQ) {
                VPRINTK("FPDMA xfer,Sctor cnt[0:7],[8:15] = %d,%d\n",
                        cd->cfis[3], cd->cfis[11]);
        }

        /* setup "ACMD - atapi command" in cmd. desc. if this is ATAPI cmd */
        if (ata_is_atapi(qc->tf.protocol)) {
                desc_info |= ATAPI_CMD;
                memset((void *)&cd->acmd, 0, 32);
                memcpy((void *)&cd->acmd, qc->cdb, qc->dev->cdb_len);
        }

        if (qc->flags & ATA_QCFLAG_DMAMAP)
                num_prde = sata_fsl_fill_sg(qc, (void *)cd,
                                            &ttl_dwords, cd_paddr,
                                            host_priv->data_snoop);

        if (qc->tf.protocol == ATA_PROT_NCQ)
                desc_info |= FPDMA_QUEUED_CMD;

        sata_fsl_setup_cmd_hdr_entry(pp, tag, desc_info, ttl_dwords,
                                     num_prde, 5);

        VPRINTK("SATA FSL : xx_qc_prep, di = 0x%x, ttl = %d, num_prde = %d\n",
                desc_info, ttl_dwords, num_prde);

        return AC_ERR_OK;
}

static unsigned int sata_fsl_qc_issue(struct ata_queued_cmd *qc)
{
        struct ata_port *ap = qc->ap;
        struct sata_fsl_host_priv *host_priv = ap->host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        unsigned int tag = sata_fsl_tag(qc->hw_tag, hcr_base);

        VPRINTK("xx_qc_issue called,CQ=0x%x,CA=0x%x,CE=0x%x,CC=0x%x\n",
                ioread32(CQ + hcr_base),
                ioread32(CA + hcr_base),
                ioread32(CE + hcr_base), ioread32(CC + hcr_base));

        iowrite32(qc->dev->link->pmp, CQPMP + hcr_base);

        /* Simply queue command to the controller/device */
        iowrite32(1 << tag, CQ + hcr_base);

        VPRINTK("xx_qc_issue called, tag=%d, CQ=0x%x, CA=0x%x\n",
                tag, ioread32(CQ + hcr_base), ioread32(CA + hcr_base));

        VPRINTK("CE=0x%x, DE=0x%x, CC=0x%x, CmdStat = 0x%x\n",
                ioread32(CE + hcr_base),
                ioread32(DE + hcr_base),
                ioread32(CC + hcr_base),
                ioread32(COMMANDSTAT + host_priv->csr_base));

        return 0;
}

static bool sata_fsl_qc_fill_rtf(struct ata_queued_cmd *qc)
{
        struct sata_fsl_port_priv *pp = qc->ap->private_data;
        struct sata_fsl_host_priv *host_priv = qc->ap->host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        unsigned int tag = sata_fsl_tag(qc->hw_tag, hcr_base);
        struct command_desc *cd;

        cd = pp->cmdentry + tag;

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

static int sata_fsl_scr_write(struct ata_link *link,
                              unsigned int sc_reg_in, u32 val)
{
        struct sata_fsl_host_priv *host_priv = link->ap->host->private_data;
        void __iomem *ssr_base = host_priv->ssr_base;
        unsigned int sc_reg;

        switch (sc_reg_in) {
        case SCR_STATUS:
        case SCR_ERROR:
        case SCR_CONTROL:
        case SCR_ACTIVE:
                sc_reg = sc_reg_in;
                break;
        default:
                return -EINVAL;
        }

        VPRINTK("xx_scr_write, reg_in = %d\n", sc_reg);

        iowrite32(val, ssr_base + (sc_reg * 4));
        return 0;
}

static int sata_fsl_scr_read(struct ata_link *link,
                             unsigned int sc_reg_in, u32 *val)
{
        struct sata_fsl_host_priv *host_priv = link->ap->host->private_data;
        void __iomem *ssr_base = host_priv->ssr_base;
        unsigned int sc_reg;

        switch (sc_reg_in) {
        case SCR_STATUS:
        case SCR_ERROR:
        case SCR_CONTROL:
        case SCR_ACTIVE:
                sc_reg = sc_reg_in;
                break;
        default:
                return -EINVAL;
        }

        VPRINTK("xx_scr_read, reg_in = %d\n", sc_reg);

        *val = ioread32(ssr_base + (sc_reg * 4));
        return 0;
}

static void sata_fsl_freeze(struct ata_port *ap)
{
        struct sata_fsl_host_priv *host_priv = ap->host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        u32 temp;

        VPRINTK("xx_freeze, CQ=0x%x, CA=0x%x, CE=0x%x, DE=0x%x\n",
                ioread32(CQ + hcr_base),
                ioread32(CA + hcr_base),
                ioread32(CE + hcr_base), ioread32(DE + hcr_base));
        VPRINTK("CmdStat = 0x%x\n",
                ioread32(host_priv->csr_base + COMMANDSTAT));

        /* disable interrupts on the controller/port */
        temp = ioread32(hcr_base + HCONTROL);
        iowrite32((temp & ~0x3F), hcr_base + HCONTROL);

        VPRINTK("in xx_freeze : HControl = 0x%x, HStatus = 0x%x\n",
                ioread32(hcr_base + HCONTROL), ioread32(hcr_base + HSTATUS));
}

static void sata_fsl_thaw(struct ata_port *ap)
{
        struct sata_fsl_host_priv *host_priv = ap->host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        u32 temp;

        /* ack. any pending IRQs for this controller/port */
        temp = ioread32(hcr_base + HSTATUS);

        VPRINTK("xx_thaw, pending IRQs = 0x%x\n", (temp & 0x3F));

        if (temp & 0x3F)
                iowrite32((temp & 0x3F), hcr_base + HSTATUS);

        /* enable interrupts on the controller/port */
        temp = ioread32(hcr_base + HCONTROL);
        iowrite32((temp | DEFAULT_PORT_IRQ_ENABLE_MASK), hcr_base + HCONTROL);

        VPRINTK("xx_thaw : HControl = 0x%x, HStatus = 0x%x\n",
                ioread32(hcr_base + HCONTROL), ioread32(hcr_base + HSTATUS));
}

static void sata_fsl_pmp_attach(struct ata_port *ap)
{
        struct sata_fsl_host_priv *host_priv = ap->host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        u32 temp;

        temp = ioread32(hcr_base + HCONTROL);
        iowrite32((temp | HCONTROL_PMP_ATTACHED), hcr_base + HCONTROL);
}

static void sata_fsl_pmp_detach(struct ata_port *ap)
{
        struct sata_fsl_host_priv *host_priv = ap->host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        u32 temp;

        temp = ioread32(hcr_base + HCONTROL);
        temp &= ~HCONTROL_PMP_ATTACHED;
        iowrite32(temp, hcr_base + HCONTROL);

        /* enable interrupts on the controller/port */
        temp = ioread32(hcr_base + HCONTROL);
        iowrite32((temp | DEFAULT_PORT_IRQ_ENABLE_MASK), hcr_base + HCONTROL);

}

static int sata_fsl_port_start(struct ata_port *ap)
{
        struct device *dev = ap->host->dev;
        struct sata_fsl_port_priv *pp;
        void *mem;
        dma_addr_t mem_dma;
        struct sata_fsl_host_priv *host_priv = ap->host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        u32 temp;

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

        mem = dma_alloc_coherent(dev, SATA_FSL_PORT_PRIV_DMA_SZ, &mem_dma,
                                 GFP_KERNEL);
        if (!mem) {
                kfree(pp);
                return -ENOMEM;
        }

        pp->cmdslot = mem;
        pp->cmdslot_paddr = mem_dma;

        mem += SATA_FSL_CMD_SLOT_SIZE;
        mem_dma += SATA_FSL_CMD_SLOT_SIZE;

        pp->cmdentry = mem;
        pp->cmdentry_paddr = mem_dma;

        ap->private_data = pp;

        VPRINTK("CHBA = 0x%x, cmdentry_phys = 0x%x\n",
                pp->cmdslot_paddr, pp->cmdentry_paddr);

        /* Now, update the CHBA register in host controller cmd register set */
        iowrite32(pp->cmdslot_paddr & 0xffffffff, hcr_base + CHBA);

        /*
         * Now, we can bring the controller on-line & also initiate
         * the COMINIT sequence, we simply return here and the boot-probing
         * & device discovery process is re-initiated by libATA using a
         * Softreset EH (dummy) session. Hence, boot probing and device
         * discovey will be part of sata_fsl_softreset() callback.
         */

        temp = ioread32(hcr_base + HCONTROL);
        iowrite32((temp | HCONTROL_ONLINE_PHY_RST), hcr_base + HCONTROL);

        VPRINTK("HStatus = 0x%x\n", ioread32(hcr_base + HSTATUS));
        VPRINTK("HControl = 0x%x\n", ioread32(hcr_base + HCONTROL));
        VPRINTK("CHBA  = 0x%x\n", ioread32(hcr_base + CHBA));

        return 0;
}

static void sata_fsl_port_stop(struct ata_port *ap)
{
        struct device *dev = ap->host->dev;
        struct sata_fsl_port_priv *pp = ap->private_data;
        struct sata_fsl_host_priv *host_priv = ap->host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        u32 temp;

        /*
         * Force host controller to go off-line, aborting current operations
         */
        temp = ioread32(hcr_base + HCONTROL);
        temp &= ~HCONTROL_ONLINE_PHY_RST;
        temp |= HCONTROL_FORCE_OFFLINE;
        iowrite32(temp, hcr_base + HCONTROL);

        /* Poll for controller to go offline - should happen immediately */
        ata_wait_register(ap, hcr_base + HSTATUS, ONLINE, ONLINE, 1, 1);

        ap->private_data = NULL;
        dma_free_coherent(dev, SATA_FSL_PORT_PRIV_DMA_SZ,
                          pp->cmdslot, pp->cmdslot_paddr);

        kfree(pp);
}

static unsigned int sata_fsl_dev_classify(struct ata_port *ap)
{
        struct sata_fsl_host_priv *host_priv = ap->host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        struct ata_taskfile tf;
        u32 temp;

        temp = ioread32(hcr_base + SIGNATURE);

        VPRINTK("raw sig = 0x%x\n", temp);
        VPRINTK("HStatus = 0x%x\n", ioread32(hcr_base + HSTATUS));
        VPRINTK("HControl = 0x%x\n", ioread32(hcr_base + HCONTROL));

        tf.lbah = (temp >> 24) & 0xff;
        tf.lbam = (temp >> 16) & 0xff;
        tf.lbal = (temp >> 8) & 0xff;
        tf.nsect = temp & 0xff;

        return ata_dev_classify(&tf);
}

static int sata_fsl_hardreset(struct ata_link *link, unsigned int *class,
                                        unsigned long deadline)
{
        struct ata_port *ap = link->ap;
        struct sata_fsl_host_priv *host_priv = ap->host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        u32 temp;
        int i = 0;
        unsigned long start_jiffies;

        DPRINTK("in xx_hardreset\n");

try_offline_again:
        /*
         * Force host controller to go off-line, aborting current operations
         */
        temp = ioread32(hcr_base + HCONTROL);
        temp &= ~HCONTROL_ONLINE_PHY_RST;
        iowrite32(temp, hcr_base + HCONTROL);

        /* Poll for controller to go offline */
        temp = ata_wait_register(ap, hcr_base + HSTATUS, ONLINE, ONLINE,
                                 1, 500);

        if (temp & ONLINE) {
                ata_port_err(ap, "Hardreset failed, not off-lined %d\n", i);

                /*
                 * Try to offline controller atleast twice
                 */
                i++;
                if (i == 2)
                        goto err;
                else
                        goto try_offline_again;
        }

        DPRINTK("hardreset, controller off-lined\n");
        VPRINTK("HStatus = 0x%x\n", ioread32(hcr_base + HSTATUS));
        VPRINTK("HControl = 0x%x\n", ioread32(hcr_base + HCONTROL));

        /*
         * PHY reset should remain asserted for atleast 1ms
         */
        ata_msleep(ap, 1);

        sata_set_spd(link);

        /*
         * Now, bring the host controller online again, this can take time
         * as PHY reset and communication establishment, 1st D2H FIS and
         * device signature update is done, on safe side assume 500ms
         * NOTE : Host online status may be indicated immediately!!
         */

        temp = ioread32(hcr_base + HCONTROL);
        temp |= (HCONTROL_ONLINE_PHY_RST | HCONTROL_SNOOP_ENABLE);
        temp |= HCONTROL_PMP_ATTACHED;
        iowrite32(temp, hcr_base + HCONTROL);

        temp = ata_wait_register(ap, hcr_base + HSTATUS, ONLINE, 0, 1, 500);

        if (!(temp & ONLINE)) {
                ata_port_err(ap, "Hardreset failed, not on-lined\n");
                goto err;
        }

        DPRINTK("hardreset, controller off-lined & on-lined\n");
        VPRINTK("HStatus = 0x%x\n", ioread32(hcr_base + HSTATUS));
        VPRINTK("HControl = 0x%x\n", ioread32(hcr_base + HCONTROL));

        /*
         * First, wait for the PHYRDY change to occur before waiting for
         * the signature, and also verify if SStatus indicates device
         * presence
         */

        temp = ata_wait_register(ap, hcr_base + HSTATUS, 0xFF, 0, 1, 500);
        if ((!(temp & 0x10)) || ata_link_offline(link)) {
                ata_port_warn(ap, "No Device OR PHYRDY change,Hstatus = 0x%x\n",
                              ioread32(hcr_base + HSTATUS));
                *class = ATA_DEV_NONE;
                return 0;
        }

        /*
         * Wait for the first D2H from device,i.e,signature update notification
         */
        start_jiffies = jiffies;
        temp = ata_wait_register(ap, hcr_base + HSTATUS, 0xFF, 0x10,
                        500, jiffies_to_msecs(deadline - start_jiffies));

        if ((temp & 0xFF) != 0x18) {
                ata_port_warn(ap, "No Signature Update\n");
                *class = ATA_DEV_NONE;
                goto do_followup_srst;
        } else {
                ata_port_info(ap, "Signature Update detected @ %d msecs\n",
                              jiffies_to_msecs(jiffies - start_jiffies));
                *class = sata_fsl_dev_classify(ap);
                return 0;
        }

do_followup_srst:
        /*
         * request libATA to perform follow-up softreset
         */
        return -EAGAIN;

err:
        return -EIO;
}

static int sata_fsl_softreset(struct ata_link *link, unsigned int *class,
                                        unsigned long deadline)
{
        struct ata_port *ap = link->ap;
        struct sata_fsl_port_priv *pp = ap->private_data;
        struct sata_fsl_host_priv *host_priv = ap->host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        int pmp = sata_srst_pmp(link);
        u32 temp;
        struct ata_taskfile tf;
        u8 *cfis;
        u32 Serror;

        DPRINTK("in xx_softreset\n");

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

        /*
         * Send a device reset (SRST) explicitly on command slot #0
         * Check : will the command queue (reg) be cleared during offlining ??
         * Also we will be online only if Phy commn. has been established
         * and device presence has been detected, therefore if we have
         * reached here, we can send a command to the target device
         */

        DPRINTK("Sending SRST/device reset\n");

        ata_tf_init(link->device, &tf);
        cfis = (u8 *) &pp->cmdentry->cfis;

        /* device reset/SRST is a control register update FIS, uses tag0 */
        sata_fsl_setup_cmd_hdr_entry(pp, 0,
                SRST_CMD | CMD_DESC_RES | CMD_DESC_SNOOP_ENABLE, 0, 0, 5);

        tf.ctl |= ATA_SRST;     /* setup SRST bit in taskfile control reg */
        ata_tf_to_fis(&tf, pmp, 0, cfis);

        DPRINTK("Dumping cfis : 0x%x, 0x%x, 0x%x, 0x%x\n",
                cfis[0], cfis[1], cfis[2], cfis[3]);

        /*
         * Queue SRST command to the controller/device, ensure that no
         * other commands are active on the controller/device
         */

        DPRINTK("@Softreset, CQ = 0x%x, CA = 0x%x, CC = 0x%x\n",
                ioread32(CQ + hcr_base),
                ioread32(CA + hcr_base), ioread32(CC + hcr_base));

        iowrite32(0xFFFF, CC + hcr_base);
        if (pmp != SATA_PMP_CTRL_PORT)
                iowrite32(pmp, CQPMP + hcr_base);
        iowrite32(1, CQ + hcr_base);

        temp = ata_wait_register(ap, CQ + hcr_base, 0x1, 0x1, 1, 5000);
        if (temp & 0x1) {
                ata_port_warn(ap, "ATA_SRST issue failed\n");

                DPRINTK("Softreset@5000,CQ=0x%x,CA=0x%x,CC=0x%x\n",
                        ioread32(CQ + hcr_base),
                        ioread32(CA + hcr_base), ioread32(CC + hcr_base));

                sata_fsl_scr_read(&ap->link, SCR_ERROR, &Serror);

                DPRINTK("HStatus = 0x%x\n", ioread32(hcr_base + HSTATUS));
                DPRINTK("HControl = 0x%x\n", ioread32(hcr_base + HCONTROL));

                DPRINTK("Serror = 0x%x\n", Serror);
                goto err;
        }

        ata_msleep(ap, 1);

        /*
         * SATA device enters reset state after receiving a Control register
         * FIS with SRST bit asserted and it awaits another H2D Control reg.
         * FIS with SRST bit cleared, then the device does internal diags &
         * initialization, followed by indicating it's initialization status
         * using ATA signature D2H register FIS to the host controller.
         */

        sata_fsl_setup_cmd_hdr_entry(pp, 0, CMD_DESC_RES | CMD_DESC_SNOOP_ENABLE,
                                      0, 0, 5);

        tf.ctl &= ~ATA_SRST;    /* 2nd H2D Ctl. register FIS */
        ata_tf_to_fis(&tf, pmp, 0, cfis);

        if (pmp != SATA_PMP_CTRL_PORT)
                iowrite32(pmp, CQPMP + hcr_base);
        iowrite32(1, CQ + hcr_base);
        ata_msleep(ap, 150);            /* ?? */

        /*
         * The above command would have signalled an interrupt on command
         * complete, which needs special handling, by clearing the Nth
         * command bit of the CCreg
         */
        iowrite32(0x01, CC + hcr_base); /* We know it will be cmd#0 always */

        DPRINTK("SATA FSL : Now checking device signature\n");

        *class = ATA_DEV_NONE;

        /* Verify if SStatus indicates device presence */
        if (ata_link_online(link)) {
                /*
                 * if we are here, device presence has been detected,
                 * 1st D2H FIS would have been received, but sfis in
                 * command desc. is not updated, but signature register
                 * would have been updated
                 */

                *class = sata_fsl_dev_classify(ap);

                DPRINTK("class = %d\n", *class);
                VPRINTK("ccreg = 0x%x\n", ioread32(hcr_base + CC));
                VPRINTK("cereg = 0x%x\n", ioread32(hcr_base + CE));
        }

        return 0;

err:
        return -EIO;
}

static void sata_fsl_error_handler(struct ata_port *ap)
{

        DPRINTK("in xx_error_handler\n");
        sata_pmp_error_handler(ap);

}

static void sata_fsl_post_internal_cmd(struct ata_queued_cmd *qc)
{
        if (qc->flags & ATA_QCFLAG_FAILED)
                qc->err_mask |= AC_ERR_OTHER;

        if (qc->err_mask) {
                /* make DMA engine forget about the failed command */

        }
}

static void sata_fsl_error_intr(struct ata_port *ap)
{
        struct sata_fsl_host_priv *host_priv = ap->host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        u32 hstatus, dereg=0, cereg = 0, SError = 0;
        unsigned int err_mask = 0, action = 0;
        int freeze = 0, abort=0;
        struct ata_link *link = NULL;
        struct ata_queued_cmd *qc = NULL;
        struct ata_eh_info *ehi;

        hstatus = ioread32(hcr_base + HSTATUS);
        cereg = ioread32(hcr_base + CE);

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

        /*
         * Handle & Clear SError
         */

        sata_fsl_scr_read(&ap->link, SCR_ERROR, &SError);
        if (unlikely(SError & 0xFFFF0000))
                sata_fsl_scr_write(&ap->link, SCR_ERROR, SError);

        DPRINTK("error_intr,hStat=0x%x,CE=0x%x,DE =0x%x,SErr=0x%x\n",
                hstatus, cereg, ioread32(hcr_base + DE), SError);

        /* handle fatal errors */
        if (hstatus & FATAL_ERROR_DECODE) {
                ehi->err_mask |= AC_ERR_ATA_BUS;
                ehi->action |= ATA_EH_SOFTRESET;

                freeze = 1;
        }

        /* Handle SDB FIS receive & notify update */
        if (hstatus & INT_ON_SNOTIFY_UPDATE)
                sata_async_notification(ap);

        /* Handle PHYRDY change notification */
        if (hstatus & INT_ON_PHYRDY_CHG) {
                DPRINTK("SATA FSL: PHYRDY change indication\n");

                /* Setup a soft-reset EH action */
                ata_ehi_hotplugged(ehi);
                ata_ehi_push_desc(ehi, "%s", "PHY RDY changed");
                freeze = 1;
        }

        /* handle single device errors */
        if (cereg) {
                /*
                 * clear the command error, also clears queue to the device
                 * in error, and we can (re)issue commands to this device.
                 * When a device is in error all commands queued into the
                 * host controller and at the device are considered aborted
                 * and the queue for that device is stopped. Now, after
                 * clearing the device error, we can issue commands to the
                 * device to interrogate it to find the source of the error.
                 */
                abort = 1;

                DPRINTK("single device error, CE=0x%x, DE=0x%x\n",
                        ioread32(hcr_base + CE), ioread32(hcr_base + DE));

                /* find out the offending link and qc */
                if (ap->nr_pmp_links) {
                        unsigned int dev_num;

                        dereg = ioread32(hcr_base + DE);
                        iowrite32(dereg, hcr_base + DE);
                        iowrite32(cereg, hcr_base + CE);

                        dev_num = ffs(dereg) - 1;
                        if (dev_num < ap->nr_pmp_links && dereg != 0) {
                                link = &ap->pmp_link[dev_num];
                                ehi = &link->eh_info;
                                qc = ata_qc_from_tag(ap, link->active_tag);
                                /*
                                 * We should consider this as non fatal error,
                                 * and TF must be updated as done below.
                                 */

                                err_mask |= AC_ERR_DEV;

                        } else {
                                err_mask |= AC_ERR_HSM;
                                action |= ATA_EH_HARDRESET;
                                freeze = 1;
                        }
                } else {
                        dereg = ioread32(hcr_base + DE);
                        iowrite32(dereg, hcr_base + DE);
                        iowrite32(cereg, hcr_base + CE);

                        qc = ata_qc_from_tag(ap, link->active_tag);
                        /*
                         * We should consider this as non fatal error,
                         * and TF must be updated as done below.
                        */
                        err_mask |= AC_ERR_DEV;
                }
        }

        /* record error info */
        if (qc)
                qc->err_mask |= err_mask;
        else
                ehi->err_mask |= err_mask;

        ehi->action |= action;

        /* 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 sata_fsl_host_intr(struct ata_port *ap)
{
        struct sata_fsl_host_priv *host_priv = ap->host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        u32 hstatus, done_mask = 0;
        struct ata_queued_cmd *qc;
        u32 SError;
        u32 tag;
        u32 status_mask = INT_ON_ERROR;

        hstatus = ioread32(hcr_base + HSTATUS);

        sata_fsl_scr_read(&ap->link, SCR_ERROR, &SError);

        /* Read command completed register */
        done_mask = ioread32(hcr_base + CC);

        /* Workaround for data length mismatch errata */
        if (unlikely(hstatus & INT_ON_DATA_LENGTH_MISMATCH)) {
                ata_qc_for_each_with_internal(ap, qc, tag) {
                        if (qc && ata_is_atapi(qc->tf.protocol)) {
                                u32 hcontrol;
                                /* Set HControl[27] to clear error registers */
                                hcontrol = ioread32(hcr_base + HCONTROL);
                                iowrite32(hcontrol | CLEAR_ERROR,
                                                hcr_base + HCONTROL);

                                /* Clear HControl[27] */
                                iowrite32(hcontrol & ~CLEAR_ERROR,
                                                hcr_base + HCONTROL);

                                /* Clear SError[E] bit */
                                sata_fsl_scr_write(&ap->link, SCR_ERROR,
                                                SError);

                                /* Ignore fatal error and device error */
                                status_mask &= ~(INT_ON_SINGL_DEVICE_ERR
                                                | INT_ON_FATAL_ERR);
                                break;
                        }
                }
        }

        if (unlikely(SError & 0xFFFF0000)) {
                DPRINTK("serror @host_intr : 0x%x\n", SError);
                sata_fsl_error_intr(ap);
        }

        if (unlikely(hstatus & status_mask)) {
                DPRINTK("error interrupt!!\n");
                sata_fsl_error_intr(ap);
                return;
        }

        VPRINTK("Status of all queues :\n");
        VPRINTK("done_mask/CC = 0x%x, CA = 0x%x, CE=0x%x,CQ=0x%x,apqa=0x%llx\n",
                done_mask,
                ioread32(hcr_base + CA),
                ioread32(hcr_base + CE),
                ioread32(hcr_base + CQ),
                ap->qc_active);

        if (done_mask & ap->qc_active) {
                int i;
                /* clear CC bit, this will also complete the interrupt */
                iowrite32(done_mask, hcr_base + CC);

                DPRINTK("Status of all queues :\n");
                DPRINTK("done_mask/CC = 0x%x, CA = 0x%x, CE=0x%x\n",
                        done_mask, ioread32(hcr_base + CA),
                        ioread32(hcr_base + CE));

                for (i = 0; i < SATA_FSL_QUEUE_DEPTH; i++) {
                        if (done_mask & (1 << i))
                                DPRINTK
                                    ("completing ncq cmd,tag=%d,CC=0x%x,CA=0x%x\n",
                                     i, ioread32(hcr_base + CC),
                                     ioread32(hcr_base + CA));
                }
                ata_qc_complete_multiple(ap, ata_qc_get_active(ap) ^ done_mask);
                return;

        } else if ((ap->qc_active & (1ULL << ATA_TAG_INTERNAL))) {
                iowrite32(1, hcr_base + CC);
                qc = ata_qc_from_tag(ap, ATA_TAG_INTERNAL);

                DPRINTK("completing non-ncq cmd, CC=0x%x\n",
                         ioread32(hcr_base + CC));

                if (qc) {
                        ata_qc_complete(qc);
                }
        } else {
                /* Spurious Interrupt!! */
                DPRINTK("spurious interrupt!!, CC = 0x%x\n",
                        ioread32(hcr_base + CC));
                iowrite32(done_mask, hcr_base + CC);
                return;
        }
}

static irqreturn_t sata_fsl_interrupt(int irq, void *dev_instance)
{
        struct ata_host *host = dev_instance;
        struct sata_fsl_host_priv *host_priv = host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        u32 interrupt_enables;
        unsigned handled = 0;
        struct ata_port *ap;

        /* ack. any pending IRQs for this controller/port */
        interrupt_enables = ioread32(hcr_base + HSTATUS);
        interrupt_enables &= 0x3F;

        DPRINTK("interrupt status 0x%x\n", interrupt_enables);

        if (!interrupt_enables)
                return IRQ_NONE;

        spin_lock(&host->lock);

        /* Assuming one port per host controller */

        ap = host->ports[0];
        if (ap) {
                sata_fsl_host_intr(ap);
        } else {
                dev_warn(host->dev, "interrupt on disabled port 0\n");
        }

        iowrite32(interrupt_enables, hcr_base + HSTATUS);
        handled = 1;

        spin_unlock(&host->lock);

        return IRQ_RETVAL(handled);
}

/*
 * Multiple ports are represented by multiple SATA controllers with
 * one port per controller
 */
static int sata_fsl_init_controller(struct ata_host *host)
{
        struct sata_fsl_host_priv *host_priv = host->private_data;
        void __iomem *hcr_base = host_priv->hcr_base;
        u32 temp;

        /*
         * NOTE : We cannot bring the controller online before setting
         * the CHBA, hence main controller initialization is done as
         * part of the port_start() callback
         */

        /* sata controller to operate in enterprise mode */
        temp = ioread32(hcr_base + HCONTROL);
        iowrite32(temp & ~HCONTROL_LEGACY, hcr_base + HCONTROL);

        /* ack. any pending IRQs for this controller/port */
        temp = ioread32(hcr_base + HSTATUS);
        if (temp & 0x3F)
                iowrite32((temp & 0x3F), hcr_base + HSTATUS);

        /* Keep interrupts disabled on the controller */
        temp = ioread32(hcr_base + HCONTROL);
        iowrite32((temp & ~0x3F), hcr_base + HCONTROL);

        /* Disable interrupt coalescing control(icc), for the moment */
        DPRINTK("icc = 0x%x\n", ioread32(hcr_base + ICC));
        iowrite32(0x01000000, hcr_base + ICC);

        /* clear error registers, SError is cleared by libATA  */
        iowrite32(0x00000FFFF, hcr_base + CE);
        iowrite32(0x00000FFFF, hcr_base + DE);

        /*
         * reset the number of command complete bits which will cause the
         * interrupt to be signaled
         */
        fsl_sata_set_irq_coalescing(host, intr_coalescing_count,
                        intr_coalescing_ticks);

        /*
         * host controller will be brought on-line, during xx_port_start()
         * callback, that should also initiate the OOB, COMINIT sequence
         */

        DPRINTK("HStatus = 0x%x\n", ioread32(hcr_base + HSTATUS));
        DPRINTK("HControl = 0x%x\n", ioread32(hcr_base + HCONTROL));

        return 0;
}

/*
 * scsi mid-layer and libata interface structures
 */
static struct scsi_host_template sata_fsl_sht = {
        ATA_NCQ_SHT("sata_fsl"),
        .can_queue = SATA_FSL_QUEUE_DEPTH,
        .sg_tablesize = SATA_FSL_MAX_PRD_USABLE,
        .dma_boundary = ATA_DMA_BOUNDARY,
};

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

        .qc_defer = ata_std_qc_defer,
        .qc_prep = sata_fsl_qc_prep,
        .qc_issue = sata_fsl_qc_issue,
        .qc_fill_rtf = sata_fsl_qc_fill_rtf,

        .scr_read = sata_fsl_scr_read,
        .scr_write = sata_fsl_scr_write,

        .freeze = sata_fsl_freeze,
        .thaw = sata_fsl_thaw,
        .softreset = sata_fsl_softreset,
        .hardreset = sata_fsl_hardreset,
        .pmp_softreset = sata_fsl_softreset,
        .error_handler = sata_fsl_error_handler,
        .post_internal_cmd = sata_fsl_post_internal_cmd,

        .port_start = sata_fsl_port_start,
        .port_stop = sata_fsl_port_stop,

        .pmp_attach = sata_fsl_pmp_attach,
        .pmp_detach = sata_fsl_pmp_detach,
};

static const struct ata_port_info sata_fsl_port_info[] = {
        {
         .flags = SATA_FSL_HOST_FLAGS,
         .pio_mask = ATA_PIO4,
         .udma_mask = ATA_UDMA6,
         .port_ops = &sata_fsl_ops,
         },
};

static int sata_fsl_probe(struct platform_device *ofdev)
{
        int retval = -ENXIO;
        void __iomem *hcr_base = NULL;
        void __iomem *ssr_base = NULL;
        void __iomem *csr_base = NULL;
        struct sata_fsl_host_priv *host_priv = NULL;
        int irq;
        struct ata_host *host = NULL;
        u32 temp;

        struct ata_port_info pi = sata_fsl_port_info[0];
        const struct ata_port_info *ppi[] = { &pi, NULL };

        dev_info(&ofdev->dev, "Sata FSL Platform/CSB Driver init\n");

        hcr_base = of_iomap(ofdev->dev.of_node, 0);
        if (!hcr_base)
                goto error_exit_with_cleanup;

        ssr_base = hcr_base + 0x100;
        csr_base = hcr_base + 0x140;

        if (!of_device_is_compatible(ofdev->dev.of_node, "fsl,mpc8315-sata")) {
                temp = ioread32(csr_base + TRANSCFG);
                temp = temp & 0xffffffe0;
                iowrite32(temp | TRANSCFG_RX_WATER_MARK, csr_base + TRANSCFG);
        }

        DPRINTK("@reset i/o = 0x%x\n", ioread32(csr_base + TRANSCFG));
        DPRINTK("sizeof(cmd_desc) = %d\n", sizeof(struct command_desc));
        DPRINTK("sizeof(#define cmd_desc) = %d\n", SATA_FSL_CMD_DESC_SIZE);

        host_priv = kzalloc(sizeof(struct sata_fsl_host_priv), GFP_KERNEL);
        if (!host_priv)
                goto error_exit_with_cleanup;

        host_priv->hcr_base = hcr_base;
        host_priv->ssr_base = ssr_base;
        host_priv->csr_base = csr_base;

        irq = irq_of_parse_and_map(ofdev->dev.of_node, 0);
        if (!irq) {
                dev_err(&ofdev->dev, "invalid irq from platform\n");
                goto error_exit_with_cleanup;
        }
        host_priv->irq = irq;

        if (of_device_is_compatible(ofdev->dev.of_node, "fsl,pq-sata-v2"))
                host_priv->data_snoop = DATA_SNOOP_ENABLE_V2;
        else
                host_priv->data_snoop = DATA_SNOOP_ENABLE_V1;

        /* allocate host structure */
        host = ata_host_alloc_pinfo(&ofdev->dev, ppi, SATA_FSL_MAX_PORTS);
        if (!host) {
                retval = -ENOMEM;
                goto error_exit_with_cleanup;
        }

        /* host->iomap is not used currently */
        host->private_data = host_priv;

        /* initialize host controller */
        sata_fsl_init_controller(host);

        /*
         * Now, register with libATA core, this will also initiate the
         * device discovery process, invoking our port_start() handler &
         * error_handler() to execute a dummy Softreset EH session
         */
        ata_host_activate(host, irq, sata_fsl_interrupt, SATA_FSL_IRQ_FLAG,
                          &sata_fsl_sht);

        host_priv->intr_coalescing.show = fsl_sata_intr_coalescing_show;
        host_priv->intr_coalescing.store = fsl_sata_intr_coalescing_store;
        sysfs_attr_init(&host_priv->intr_coalescing.attr);
        host_priv->intr_coalescing.attr.name = "intr_coalescing";
        host_priv->intr_coalescing.attr.mode = S_IRUGO | S_IWUSR;
        retval = device_create_file(host->dev, &host_priv->intr_coalescing);
        if (retval)
                goto error_exit_with_cleanup;

        host_priv->rx_watermark.show = fsl_sata_rx_watermark_show;
        host_priv->rx_watermark.store = fsl_sata_rx_watermark_store;
        sysfs_attr_init(&host_priv->rx_watermark.attr);
        host_priv->rx_watermark.attr.name = "rx_watermark";
        host_priv->rx_watermark.attr.mode = S_IRUGO | S_IWUSR;
        retval = device_create_file(host->dev, &host_priv->rx_watermark);
        if (retval) {
                device_remove_file(&ofdev->dev, &host_priv->intr_coalescing);
                goto error_exit_with_cleanup;
        }

        return 0;

error_exit_with_cleanup:

        if (host)
                ata_host_detach(host);

        if (hcr_base)
                iounmap(hcr_base);
        kfree(host_priv);

        return retval;
}

static int sata_fsl_remove(struct platform_device *ofdev)
{
        struct ata_host *host = platform_get_drvdata(ofdev);
        struct sata_fsl_host_priv *host_priv = host->private_data;

        device_remove_file(&ofdev->dev, &host_priv->intr_coalescing);
        device_remove_file(&ofdev->dev, &host_priv->rx_watermark);

        ata_host_detach(host);

        irq_dispose_mapping(host_priv->irq);
        iounmap(host_priv->hcr_base);
        kfree(host_priv);

        return 0;
}

#ifdef CONFIG_PM_SLEEP
static int sata_fsl_suspend(struct platform_device *op, pm_message_t state)
{
        struct ata_host *host = platform_get_drvdata(op);
        return ata_host_suspend(host, state);
}

static int sata_fsl_resume(struct platform_device *op)
{
        struct ata_host *host = platform_get_drvdata(op);
        struct sata_fsl_host_priv *host_priv = host->private_data;
        int ret;
        void __iomem *hcr_base = host_priv->hcr_base;
        struct ata_port *ap = host->ports[0];
        struct sata_fsl_port_priv *pp = ap->private_data;

        ret = sata_fsl_init_controller(host);
        if (ret) {
                dev_err(&op->dev, "Error initializing hardware\n");
                return ret;
        }

        /* Recovery the CHBA register in host controller cmd register set */
        iowrite32(pp->cmdslot_paddr & 0xffffffff, hcr_base + CHBA);

        iowrite32((ioread32(hcr_base + HCONTROL)
                                | HCONTROL_ONLINE_PHY_RST
                                | HCONTROL_SNOOP_ENABLE
                                | HCONTROL_PMP_ATTACHED),
                        hcr_base + HCONTROL);

        ata_host_resume(host);
        return 0;
}
#endif

static const struct of_device_id fsl_sata_match[] = {
        {
                .compatible = "fsl,pq-sata",
        },
        {
                .compatible = "fsl,pq-sata-v2",
        },
        {},
};

MODULE_DEVICE_TABLE(of, fsl_sata_match);

static struct platform_driver fsl_sata_driver = {
        .driver = {
                .name = "fsl-sata",
                .of_match_table = fsl_sata_match,
        },
        .probe          = sata_fsl_probe,
        .remove         = sata_fsl_remove,
#ifdef CONFIG_PM_SLEEP
        .suspend        = sata_fsl_suspend,
        .resume         = sata_fsl_resume,
#endif
};

module_platform_driver(fsl_sata_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ashish Kalra, Freescale Semiconductor");
MODULE_DESCRIPTION("Freescale 3.0Gbps SATA controller low level driver");
MODULE_VERSION("1.10");