linux/drivers/ata/ahci.c

/*
 *  ahci.c - AHCI SATA support
 *
 *  Maintained by:  Jeff Garzik <jgarzik@pobox.com>
 *    		    Please ALWAYS copy linux-ide@vger.kernel.org
 *		    on emails.
 *
 *  Copyright 2004-2005 Red Hat, Inc.
 *
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; see the file COPYING.  If not, write to
 *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *
 * libata documentation is available via 'make {ps|pdf}docs',
 * as Documentation/DocBook/libata.*
 *
 * AHCI hardware documentation:
 * http://www.intel.com/technology/serialata/pdf/rev1_0.pdf
 * http://www.intel.com/technology/serialata/pdf/rev1_1.pdf
 *
 */

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

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

/* Enclosure Management Control */
#define EM_CTRL_MSG_TYPE              0x000f0000

/* Enclosure Management LED Message Type */
#define EM_MSG_LED_HBA_PORT           0x0000000f
#define EM_MSG_LED_PMP_SLOT           0x0000ff00
#define EM_MSG_LED_VALUE              0xffff0000
#define EM_MSG_LED_VALUE_ACTIVITY     0x00070000
#define EM_MSG_LED_VALUE_OFF          0xfff80000
#define EM_MSG_LED_VALUE_ON           0x00010000

static int ahci_skip_host_reset;
static int ahci_ignore_sss;

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

module_param_named(ignore_sss, ahci_ignore_sss, int, 0444);
MODULE_PARM_DESC(ignore_sss, "Ignore staggered spinup flag (0=don't ignore, 1=ignore)");

static int ahci_enable_alpm(struct ata_port *ap,
		enum link_pm policy);
static void ahci_disable_alpm(struct ata_port *ap);
static ssize_t ahci_led_show(struct ata_port *ap, char *buf);
static ssize_t ahci_led_store(struct ata_port *ap, const char *buf,
			      size_t size);
static ssize_t ahci_transmit_led_message(struct ata_port *ap, u32 state,
					ssize_t size);

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

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

	board_ahci		= 0,
	board_ahci_vt8251	= 1,
	board_ahci_ign_iferr	= 2,
	board_ahci_sb600	= 3,
	board_ahci_mv		= 4,
	board_ahci_sb700	= 5, /* for SB700 and SB800 */
	board_ahci_mcp65	= 6,
	board_ahci_nopmp	= 7,
	board_ahci_yesncq	= 8,
	board_ahci_nosntf	= 9,

	/* global controller registers */
	HOST_CAP		= 0x00, /* host capabilities */
	HOST_CTL		= 0x04, /* global host control */
	HOST_IRQ_STAT		= 0x08, /* interrupt status */
	HOST_PORTS_IMPL		= 0x0c, /* bitmap of implemented ports */
	HOST_VERSION		= 0x10, /* AHCI spec. version compliancy */
	HOST_EM_LOC		= 0x1c, /* Enclosure Management location */
	HOST_EM_CTL		= 0x20, /* Enclosure Management Control */
	HOST_CAP2		= 0x24, /* host capabilities, extended */

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

	/* HOST_CAP bits */
	HOST_CAP_SXS		= (1 << 5),  /* Supports External SATA */
	HOST_CAP_EMS		= (1 << 6),  /* Enclosure Management support */
	HOST_CAP_CCC		= (1 << 7),  /* Command Completion Coalescing */
	HOST_CAP_PART		= (1 << 13), /* Partial state capable */
	HOST_CAP_SSC		= (1 << 14), /* Slumber state capable */
	HOST_CAP_PIO_MULTI	= (1 << 15), /* PIO multiple DRQ support */
	HOST_CAP_FBS		= (1 << 16), /* FIS-based switching support */
	HOST_CAP_PMP		= (1 << 17), /* Port Multiplier support */
	HOST_CAP_ONLY		= (1 << 18), /* Supports AHCI mode only */
	HOST_CAP_CLO		= (1 << 24), /* Command List Override support */
	HOST_CAP_LED		= (1 << 25), /* Supports activity LED */
	HOST_CAP_ALPM		= (1 << 26), /* Aggressive Link PM support */
	HOST_CAP_SSS		= (1 << 27), /* Staggered Spin-up */
	HOST_CAP_MPS		= (1 << 28), /* Mechanical presence switch */
	HOST_CAP_SNTF		= (1 << 29), /* SNotification register */
	HOST_CAP_NCQ		= (1 << 30), /* Native Command Queueing */
	HOST_CAP_64		= (1 << 31), /* PCI DAC (64-bit DMA) support */

	/* HOST_CAP2 bits */
	HOST_CAP2_BOH		= (1 << 0),  /* BIOS/OS handoff supported */
	HOST_CAP2_NVMHCI	= (1 << 1),  /* NVMHCI supported */
	HOST_CAP2_APST		= (1 << 2),  /* Automatic partial to slumber */

	/* registers for each SATA port */
	PORT_LST_ADDR		= 0x00, /* command list DMA addr */
	PORT_LST_ADDR_HI	= 0x04, /* command list DMA addr hi */
	PORT_FIS_ADDR		= 0x08, /* FIS rx buf addr */
	PORT_FIS_ADDR_HI	= 0x0c, /* FIS rx buf addr hi */
	PORT_IRQ_STAT		= 0x10, /* interrupt status */
	PORT_IRQ_MASK		= 0x14, /* interrupt enable/disable mask */
	PORT_CMD		= 0x18, /* port command */
	PORT_TFDATA		= 0x20,	/* taskfile data */
	PORT_SIG		= 0x24,	/* device TF signature */
	PORT_CMD_ISSUE		= 0x38, /* command issue */
	PORT_SCR_STAT		= 0x28, /* SATA phy register: SStatus */
	PORT_SCR_CTL		= 0x2c, /* SATA phy register: SControl */
	PORT_SCR_ERR		= 0x30, /* SATA phy register: SError */
	PORT_SCR_ACT		= 0x34, /* SATA phy register: SActive */
	PORT_SCR_NTF		= 0x3c, /* SATA phy register: SNotification */
	PORT_FBS		= 0x40, /* FIS-based Switching */

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

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

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

	/* PORT_CMD bits */
	PORT_CMD_ASP		= (1 << 27), /* Aggressive Slumber/Partial */
	PORT_CMD_ALPE		= (1 << 26), /* Aggressive Link PM enable */
	PORT_CMD_ATAPI		= (1 << 24), /* Device is ATAPI */
	PORT_CMD_FBSCP		= (1 << 22), /* FBS Capable Port */
	PORT_CMD_PMP		= (1 << 17), /* PMP attached */
	PORT_CMD_LIST_ON	= (1 << 15), /* cmd list DMA engine running */
	PORT_CMD_FIS_ON		= (1 << 14), /* FIS DMA engine running */
	PORT_CMD_FIS_RX		= (1 << 4), /* Enable FIS receive DMA engine */
	PORT_CMD_CLO		= (1 << 3), /* Command list override */
	PORT_CMD_POWER_ON	= (1 << 2), /* Power up device */
	PORT_CMD_SPIN_UP	= (1 << 1), /* Spin up device */
	PORT_CMD_START		= (1 << 0), /* Enable port DMA engine */

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

	PORT_FBS_DWE_OFFSET	= 16, /* FBS device with error offset */
	PORT_FBS_ADO_OFFSET	= 12, /* FBS active dev optimization offset */
	PORT_FBS_DEV_OFFSET	= 8,  /* FBS device to issue offset */
	PORT_FBS_DEV_MASK	= (0xf << PORT_FBS_DEV_OFFSET),  /* FBS.DEV */
	PORT_FBS_SDE		= (1 << 2), /* FBS single device error */
	PORT_FBS_DEC		= (1 << 1), /* FBS device error clear */
	PORT_FBS_EN		= (1 << 0), /* Enable FBS */

	/* hpriv->flags bits */
	AHCI_HFLAG_NO_NCQ		= (1 << 0),
	AHCI_HFLAG_IGN_IRQ_IF_ERR	= (1 << 1), /* ignore IRQ_IF_ERR */
	AHCI_HFLAG_IGN_SERR_INTERNAL	= (1 << 2), /* ignore SERR_INTERNAL */
	AHCI_HFLAG_32BIT_ONLY		= (1 << 3), /* force 32bit */
	AHCI_HFLAG_MV_PATA		= (1 << 4), /* PATA port */
	AHCI_HFLAG_NO_MSI		= (1 << 5), /* no PCI MSI */
	AHCI_HFLAG_NO_PMP		= (1 << 6), /* no PMP */
	AHCI_HFLAG_NO_HOTPLUG		= (1 << 7), /* ignore PxSERR.DIAG.N */
	AHCI_HFLAG_SECT255		= (1 << 8), /* max 255 sectors */
	AHCI_HFLAG_YES_NCQ		= (1 << 9), /* force NCQ cap on */
	AHCI_HFLAG_NO_SUSPEND		= (1 << 10), /* don't suspend */
	AHCI_HFLAG_SRST_TOUT_IS_OFFLINE	= (1 << 11), /* treat SRST timeout as
							link offline */
	AHCI_HFLAG_NO_SNTF		= (1 << 12), /* no sntf */

	/* ap->flags bits */

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

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

	/* em constants */
	EM_MAX_SLOTS			= 8,
	EM_MAX_RETRY			= 5,

	/* em_ctl bits */
	EM_CTL_RST			= (1 << 9), /* Reset */
	EM_CTL_TM			= (1 << 8), /* Transmit Message */
	EM_CTL_ALHD			= (1 << 26), /* Activity LED */
};

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

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

struct ahci_em_priv {
	enum sw_activity blink_policy;
	struct timer_list timer;
	unsigned long saved_activity;
	unsigned long activity;
	unsigned long led_state;
};

struct ahci_host_priv {
	void __iomem *		mmio;		/* bus-independant mem map */
	unsigned int		flags;		/* AHCI_HFLAG_* */
	u32			cap;		/* cap to use */
	u32			cap2;		/* cap2 to use */
	u32			port_map;	/* port map to use */
	u32			saved_cap;	/* saved initial cap */
	u32			saved_cap2;	/* saved initial cap2 */
	u32			saved_port_map;	/* saved initial port_map */
	u32 			em_loc; /* enclosure management location */
};

struct ahci_port_priv {
	struct ata_link		*active_link;
	struct ahci_cmd_hdr	*cmd_slot;
	dma_addr_t		cmd_slot_dma;
	void			*cmd_tbl;
	dma_addr_t		cmd_tbl_dma;
	void			*rx_fis;
	dma_addr_t		rx_fis_dma;
	/* for NCQ spurious interrupt analysis */
	unsigned int		ncq_saw_d2h:1;
	unsigned int		ncq_saw_dmas:1;
	unsigned int		ncq_saw_sdb:1;
	u32 			intr_mask;	/* interrupts to enable */
	bool			fbs_supported;	/* set iff FBS is supported */
	bool			fbs_enabled;	/* set iff FBS is enabled */
	int			fbs_last_dev;	/* save FBS.DEV of last FIS */
	/* enclosure management info per PM slot */
	struct ahci_em_priv	em_priv[EM_MAX_SLOTS];
};

static int ahci_scr_read(struct ata_link *link, unsigned int sc_reg, u32 *val);
static int ahci_scr_write(struct ata_link *link, unsigned int sc_reg, u32 val);
static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent);
static unsigned int ahci_qc_issue(struct ata_queued_cmd *qc);
static bool ahci_qc_fill_rtf(struct ata_queued_cmd *qc);
static int ahci_port_start(struct ata_port *ap);
static void ahci_port_stop(struct ata_port *ap);
static int ahci_pmp_qc_defer(struct ata_queued_cmd *qc);
static void ahci_qc_prep(struct ata_queued_cmd *qc);
static void ahci_freeze(struct ata_port *ap);
static void ahci_thaw(struct ata_port *ap);
static void ahci_enable_fbs(struct ata_port *ap);
static void ahci_disable_fbs(struct ata_port *ap);
static void ahci_pmp_attach(struct ata_port *ap);
static void ahci_pmp_detach(struct ata_port *ap);
static int ahci_softreset(struct ata_link *link, unsigned int *class,
			  unsigned long deadline);
static int ahci_sb600_softreset(struct ata_link *link, unsigned int *class,
			  unsigned long deadline);
static int ahci_hardreset(struct ata_link *link, unsigned int *class,
			  unsigned long deadline);
static int ahci_vt8251_hardreset(struct ata_link *link, unsigned int *class,
				 unsigned long deadline);
static int ahci_p5wdh_hardreset(struct ata_link *link, unsigned int *class,
				unsigned long deadline);
static void ahci_postreset(struct ata_link *link, unsigned int *class);
static void ahci_error_handler(struct ata_port *ap);
static void ahci_post_internal_cmd(struct ata_queued_cmd *qc);
static int ahci_port_resume(struct ata_port *ap);
static void ahci_dev_config(struct ata_device *dev);
static void ahci_fill_cmd_slot(struct ahci_port_priv *pp, unsigned int tag,
			       u32 opts);
#ifdef CONFIG_PM
static int ahci_port_suspend(struct ata_port *ap, pm_message_t mesg);
static int ahci_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg);
static int ahci_pci_device_resume(struct pci_dev *pdev);
#endif
static ssize_t ahci_activity_show(struct ata_device *dev, char *buf);
static ssize_t ahci_activity_store(struct ata_device *dev,
				   enum sw_activity val);
static void ahci_init_sw_activity(struct ata_link *link);

static ssize_t ahci_show_host_caps(struct device *dev,
				   struct device_attribute *attr, char *buf);
static ssize_t ahci_show_host_cap2(struct device *dev,
				   struct device_attribute *attr, char *buf);
static ssize_t ahci_show_host_version(struct device *dev,
				      struct device_attribute *attr, char *buf);
static ssize_t ahci_show_port_cmd(struct device *dev,
				  struct device_attribute *attr, char *buf);

static DEVICE_ATTR(ahci_host_caps, S_IRUGO, ahci_show_host_caps, NULL);
static DEVICE_ATTR(ahci_host_cap2, S_IRUGO, ahci_show_host_cap2, NULL);
static DEVICE_ATTR(ahci_host_version, S_IRUGO, ahci_show_host_version, NULL);
static DEVICE_ATTR(ahci_port_cmd, S_IRUGO, ahci_show_port_cmd, NULL);

static struct device_attribute *ahci_shost_attrs[] = {
	&dev_attr_link_power_management_policy,
	&dev_attr_em_message_type,
	&dev_attr_em_message,
	&dev_attr_ahci_host_caps,
	&dev_attr_ahci_host_cap2,
	&dev_attr_ahci_host_version,
	&dev_attr_ahci_port_cmd,
	NULL
};

static struct device_attribute *ahci_sdev_attrs[] = {
	&dev_attr_sw_activity,
	&dev_attr_unload_heads,
	NULL
};

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

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

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

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

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

	.enable_pm		= ahci_enable_alpm,
	.disable_pm		= ahci_disable_alpm,
	.em_show		= ahci_led_show,
	.em_store		= ahci_led_store,
	.sw_activity_show	= ahci_activity_show,
	.sw_activity_store	= ahci_activity_store,
#ifdef CONFIG_PM
	.port_suspend		= ahci_port_suspend,
	.port_resume		= ahci_port_resume,
#endif
	.port_start		= ahci_port_start,
	.port_stop		= ahci_port_stop,
};

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

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

static struct ata_port_operations ahci_sb600_ops = {
	.inherits		= &ahci_ops,
	.softreset		= ahci_sb600_softreset,
	.pmp_softreset		= ahci_sb600_softreset,
};

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

static const struct ata_port_info ahci_port_info[] = {
	[board_ahci] =
	{
		.flags		= AHCI_FLAG_COMMON,
		.pio_mask	= ATA_PIO4,
		.udma_mask	= ATA_UDMA6,
		.port_ops	= &ahci_ops,
	},
	[board_ahci_vt8251] =
	{
		AHCI_HFLAGS	(AHCI_HFLAG_NO_NCQ | AHCI_HFLAG_NO_PMP),
		.flags		= AHCI_FLAG_COMMON,
		.pio_mask	= ATA_PIO4,
		.udma_mask	= ATA_UDMA6,
		.port_ops	= &ahci_vt8251_ops,
	},
	[board_ahci_ign_iferr] =
	{
		AHCI_HFLAGS	(AHCI_HFLAG_IGN_IRQ_IF_ERR),
		.flags		= AHCI_FLAG_COMMON,
		.pio_mask	= ATA_PIO4,
		.udma_mask	= ATA_UDMA6,
		.port_ops	= &ahci_ops,
	},
	[board_ahci_sb600] =
	{
		AHCI_HFLAGS	(AHCI_HFLAG_IGN_SERR_INTERNAL |
				 AHCI_HFLAG_NO_MSI | AHCI_HFLAG_SECT255 |
				 AHCI_HFLAG_32BIT_ONLY),
		.flags		= AHCI_FLAG_COMMON,
		.pio_mask	= ATA_PIO4,
		.udma_mask	= ATA_UDMA6,
		.port_ops	= &ahci_sb600_ops,
	},
	[board_ahci_mv] =
	{
		AHCI_HFLAGS	(AHCI_HFLAG_NO_NCQ | AHCI_HFLAG_NO_MSI |
				 AHCI_HFLAG_MV_PATA | AHCI_HFLAG_NO_PMP),
		.flags		= ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
				  ATA_FLAG_MMIO | ATA_FLAG_PIO_DMA,
		.pio_mask	= ATA_PIO4,
		.udma_mask	= ATA_UDMA6,
		.port_ops	= &ahci_ops,
	},
	[board_ahci_sb700] =	/* for SB700 and SB800 */
	{
		AHCI_HFLAGS	(AHCI_HFLAG_IGN_SERR_INTERNAL),
		.flags		= AHCI_FLAG_COMMON,
		.pio_mask	= ATA_PIO4,
		.udma_mask	= ATA_UDMA6,
		.port_ops	= &ahci_sb600_ops,
	},
	[board_ahci_mcp65] =
	{
		AHCI_HFLAGS	(AHCI_HFLAG_YES_NCQ),
		.flags		= AHCI_FLAG_COMMON,
		.pio_mask	= ATA_PIO4,
		.udma_mask	= ATA_UDMA6,
		.port_ops	= &ahci_ops,
	},
	[board_ahci_nopmp] =
	{
		AHCI_HFLAGS	(AHCI_HFLAG_NO_PMP),
		.flags		= AHCI_FLAG_COMMON,
		.pio_mask	= ATA_PIO4,
		.udma_mask	= ATA_UDMA6,
		.port_ops	= &ahci_ops,
	},
	[board_ahci_yesncq] =
	{
		AHCI_HFLAGS	(AHCI_HFLAG_YES_NCQ),
		.flags		= AHCI_FLAG_COMMON,
		.pio_mask	= ATA_PIO4,
		.udma_mask	= ATA_UDMA6,
		.port_ops	= &ahci_ops,
	},
	[board_ahci_nosntf] =
	{
		AHCI_HFLAGS	(AHCI_HFLAG_NO_SNTF),
		.flags		= AHCI_FLAG_COMMON,
		.pio_mask	= ATA_PIO4,
		.udma_mask	= ATA_UDMA6,
		.port_ops	= &ahci_ops,
	},
};

static const struct pci_device_id ahci_pci_tbl[] = {
	/* Intel */
	{ PCI_VDEVICE(INTEL, 0x2652), board_ahci }, /* ICH6 */
	{ PCI_VDEVICE(INTEL, 0x2653), board_ahci }, /* ICH6M */
	{ PCI_VDEVICE(INTEL, 0x27c1), board_ahci }, /* ICH7 */
	{ PCI_VDEVICE(INTEL, 0x27c5), board_ahci }, /* ICH7M */
	{ PCI_VDEVICE(INTEL, 0x27c3), board_ahci }, /* ICH7R */
	{ PCI_VDEVICE(AL, 0x5288), board_ahci_ign_iferr }, /* ULi M5288 */
	{ PCI_VDEVICE(INTEL, 0x2681), board_ahci }, /* ESB2 */
	{ PCI_VDEVICE(INTEL, 0x2682), board_ahci }, /* ESB2 */
	{ PCI_VDEVICE(INTEL, 0x2683), board_ahci }, /* ESB2 */
	{ PCI_VDEVICE(INTEL, 0x27c6), board_ahci }, /* ICH7-M DH */
	{ PCI_VDEVICE(INTEL, 0x2821), board_ahci }, /* ICH8 */
	{ PCI_VDEVICE(INTEL, 0x2822), board_ahci_nosntf }, /* ICH8 */
	{ PCI_VDEVICE(INTEL, 0x2824), board_ahci }, /* ICH8 */
	{ PCI_VDEVICE(INTEL, 0x2829), board_ahci }, /* ICH8M */
	{ PCI_VDEVICE(INTEL, 0x282a), board_ahci }, /* ICH8M */
	{ PCI_VDEVICE(INTEL, 0x2922), board_ahci }, /* ICH9 */
	{ PCI_VDEVICE(INTEL, 0x2923), board_ahci }, /* ICH9 */
	{ PCI_VDEVICE(INTEL, 0x2924), board_ahci }, /* ICH9 */
	{ PCI_VDEVICE(INTEL, 0x2925), board_ahci }, /* ICH9 */
	{ PCI_VDEVICE(INTEL, 0x2927), board_ahci }, /* ICH9 */
	{ PCI_VDEVICE(INTEL, 0x2929), board_ahci }, /* ICH9M */
	{ PCI_VDEVICE(INTEL, 0x292a), board_ahci }, /* ICH9M */
	{ PCI_VDEVICE(INTEL, 0x292b), board_ahci }, /* ICH9M */
	{ PCI_VDEVICE(INTEL, 0x292c), board_ahci }, /* ICH9M */
	{ PCI_VDEVICE(INTEL, 0x292f), board_ahci }, /* ICH9M */
	{ PCI_VDEVICE(INTEL, 0x294d), board_ahci }, /* ICH9 */
	{ PCI_VDEVICE(INTEL, 0x294e), board_ahci }, /* ICH9M */
	{ PCI_VDEVICE(INTEL, 0x502a), board_ahci }, /* Tolapai */
	{ PCI_VDEVICE(INTEL, 0x502b), board_ahci }, /* Tolapai */
	{ PCI_VDEVICE(INTEL, 0x3a05), board_ahci }, /* ICH10 */
	{ PCI_VDEVICE(INTEL, 0x3a22), board_ahci }, /* ICH10 */
	{ PCI_VDEVICE(INTEL, 0x3a25), board_ahci }, /* ICH10 */
	{ PCI_VDEVICE(INTEL, 0x3b22), board_ahci }, /* PCH AHCI */
	{ PCI_VDEVICE(INTEL, 0x3b23), board_ahci }, /* PCH AHCI */
	{ PCI_VDEVICE(INTEL, 0x3b24), board_ahci }, /* PCH RAID */
	{ PCI_VDEVICE(INTEL, 0x3b25), board_ahci }, /* PCH RAID */
	{ PCI_VDEVICE(INTEL, 0x3b29), board_ahci }, /* PCH AHCI */
	{ PCI_VDEVICE(INTEL, 0x3b2b), board_ahci }, /* PCH RAID */
	{ PCI_VDEVICE(INTEL, 0x3b2c), board_ahci }, /* PCH RAID */
	{ PCI_VDEVICE(INTEL, 0x3b2f), board_ahci }, /* PCH AHCI */
	{ PCI_VDEVICE(INTEL, 0x1c02), board_ahci }, /* CPT AHCI */
	{ PCI_VDEVICE(INTEL, 0x1c03), board_ahci }, /* CPT AHCI */
	{ PCI_VDEVICE(INTEL, 0x1c04), board_ahci }, /* CPT RAID */
	{ PCI_VDEVICE(INTEL, 0x1c05), board_ahci }, /* CPT RAID */
	{ PCI_VDEVICE(INTEL, 0x1c06), board_ahci }, /* CPT RAID */
	{ PCI_VDEVICE(INTEL, 0x1c07), board_ahci }, /* CPT RAID */

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

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

	/* AMD */
	{ PCI_VDEVICE(AMD, 0x7800), board_ahci }, /* AMD Hudson-2 */
	/* AMD is using RAID class only for ahci controllers */
	{ PCI_VENDOR_ID_AMD, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
	  PCI_CLASS_STORAGE_RAID << 8, 0xffffff, board_ahci },

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

	/* NVIDIA */
	{ PCI_VDEVICE(NVIDIA, 0x044c), board_ahci_mcp65 },	/* MCP65 */
	{ PCI_VDEVICE(NVIDIA, 0x044d), board_ahci_mcp65 },	/* MCP65 */
	{ PCI_VDEVICE(NVIDIA, 0x044e), board_ahci_mcp65 },	/* MCP65 */
	{ PCI_VDEVICE(NVIDIA, 0x044f), board_ahci_mcp65 },	/* MCP65 */
	{ PCI_VDEVICE(NVIDIA, 0x045c), board_ahci_mcp65 },	/* MCP65 */
	{ PCI_VDEVICE(NVIDIA, 0x045d), board_ahci_mcp65 },	/* MCP65 */
	{ PCI_VDEVICE(NVIDIA, 0x045e), board_ahci_mcp65 },	/* MCP65 */
	{ PCI_VDEVICE(NVIDIA, 0x045f), board_ahci_mcp65 },	/* MCP65 */
	{ PCI_VDEVICE(NVIDIA, 0x0550), board_ahci_yesncq },	/* MCP67 */
	{ PCI_VDEVICE(NVIDIA, 0x0551), board_ahci_yesncq },	/* MCP67 */
	{ PCI_VDEVICE(NVIDIA, 0x0552), board_ahci_yesncq },	/* MCP67 */
	{ PCI_VDEVICE(NVIDIA, 0x0553), board_ahci_yesncq },	/* MCP67 */
	{ PCI_VDEVICE(NVIDIA, 0x0554), board_ahci_yesncq },	/* MCP67 */
	{ PCI_VDEVICE(NVIDIA, 0x0555), board_ahci_yesncq },	/* MCP67 */
	{ PCI_VDEVICE(NVIDIA, 0x0556), board_ahci_yesncq },	/* MCP67 */
	{ PCI_VDEVICE(NVIDIA, 0x0557), board_ahci_yesncq },	/* MCP67 */
	{ PCI_VDEVICE(NVIDIA, 0x0558), board_ahci_yesncq },	/* MCP67 */
	{ PCI_VDEVICE(NVIDIA, 0x0559), board_ahci_yesncq },	/* MCP67 */
	{ PCI_VDEVICE(NVIDIA, 0x055a), board_ahci_yesncq },	/* MCP67 */
	{ PCI_VDEVICE(NVIDIA, 0x055b), board_ahci_yesncq },	/* MCP67 */
	{ PCI_VDEVICE(NVIDIA, 0x0580), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x0581), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x0582), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x0583), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x0584), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x0585), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x0586), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x0587), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x0588), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x0589), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x058a), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x058b), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x058c), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x058d), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x058e), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x058f), board_ahci_yesncq },	/* Linux ID */
	{ PCI_VDEVICE(NVIDIA, 0x07f0), board_ahci_yesncq },	/* MCP73 */
	{ PCI_VDEVICE(NVIDIA, 0x07f1), board_ahci_yesncq },	/* MCP73 */
	{ PCI_VDEVICE(NVIDIA, 0x07f2), board_ahci_yesncq },	/* MCP73 */
	{ PCI_VDEVICE(NVIDIA, 0x07f3), board_ahci_yesncq },	/* MCP73 */
	{ PCI_VDEVICE(NVIDIA, 0x07f4), board_ahci_yesncq },	/* MCP73 */
	{ PCI_VDEVICE(NVIDIA, 0x07f5), board_ahci_yesncq },	/* MCP73 */
	{ PCI_VDEVICE(NVIDIA, 0x07f6), board_ahci_yesncq },	/* MCP73 */
	{ PCI_VDEVICE(NVIDIA, 0x07f7), board_ahci_yesncq },	/* MCP73 */
	{ PCI_VDEVICE(NVIDIA, 0x07f8), board_ahci_yesncq },	/* MCP73 */
	{ PCI_VDEVICE(NVIDIA, 0x07f9), board_ahci_yesncq },	/* MCP73 */
	{ PCI_VDEVICE(NVIDIA, 0x07fa), board_ahci_yesncq },	/* MCP73 */
	{ PCI_VDEVICE(NVIDIA, 0x07fb), board_ahci_yesncq },	/* MCP73 */
	{ PCI_VDEVICE(NVIDIA, 0x0ad0), board_ahci },		/* MCP77 */
	{ PCI_VDEVICE(NVIDIA, 0x0ad1), board_ahci },		/* MCP77 */
	{ PCI_VDEVICE(NVIDIA, 0x0ad2), board_ahci },		/* MCP77 */
	{ PCI_VDEVICE(NVIDIA, 0x0ad3), board_ahci },		/* MCP77 */
	{ PCI_VDEVICE(NVIDIA, 0x0ad4), board_ahci },		/* MCP77 */
	{ PCI_VDEVICE(NVIDIA, 0x0ad5), board_ahci },		/* MCP77 */
	{ PCI_VDEVICE(NVIDIA, 0x0ad6), board_ahci },		/* MCP77 */
	{ PCI_VDEVICE(NVIDIA, 0x0ad7), board_ahci },		/* MCP77 */
	{ PCI_VDEVICE(NVIDIA, 0x0ad8), board_ahci },		/* MCP77 */
	{ PCI_VDEVICE(NVIDIA, 0x0ad9), board_ahci },		/* MCP77 */
	{ PCI_VDEVICE(NVIDIA, 0x0ada), board_ahci },		/* MCP77 */
	{ PCI_VDEVICE(NVIDIA, 0x0adb), board_ahci },		/* MCP77 */
	{ PCI_VDEVICE(NVIDIA, 0x0ab4), board_ahci },		/* MCP79 */
	{ PCI_VDEVICE(NVIDIA, 0x0ab5), board_ahci },		/* MCP79 */
	{ PCI_VDEVICE(NVIDIA, 0x0ab6), board_ahci },		/* MCP79 */
	{ PCI_VDEVICE(NVIDIA, 0x0ab7), board_ahci },		/* MCP79 */
	{ PCI_VDEVICE(NVIDIA, 0x0ab8), board_ahci },		/* MCP79 */
	{ PCI_VDEVICE(NVIDIA, 0x0ab9), board_ahci },		/* MCP79 */
	{ PCI_VDEVICE(NVIDIA, 0x0aba), board_ahci },		/* MCP79 */
	{ PCI_VDEVICE(NVIDIA, 0x0abb), board_ahci },		/* MCP79 */
	{ PCI_VDEVICE(NVIDIA, 0x0abc), board_ahci },		/* MCP79 */
	{ PCI_VDEVICE(NVIDIA, 0x0abd), board_ahci },		/* MCP79 */
	{ PCI_VDEVICE(NVIDIA, 0x0abe), board_ahci },		/* MCP79 */
	{ PCI_VDEVICE(NVIDIA, 0x0abf), board_ahci },		/* MCP79 */
	{ PCI_VDEVICE(NVIDIA, 0x0d84), board_ahci },		/* MCP89 */
	{ PCI_VDEVICE(NVIDIA, 0x0d85), board_ahci },		/* MCP89 */
	{ PCI_VDEVICE(NVIDIA, 0x0d86), board_ahci },		/* MCP89 */
	{ PCI_VDEVICE(NVIDIA, 0x0d87), board_ahci },		/* MCP89 */
	{ PCI_VDEVICE(NVIDIA, 0x0d88), board_ahci },		/* MCP89 */
	{ PCI_VDEVICE(NVIDIA, 0x0d89), board_ahci },		/* MCP89 */
	{ PCI_VDEVICE(NVIDIA, 0x0d8a), board_ahci },		/* MCP89 */
	{ PCI_VDEVICE(NVIDIA, 0x0d8b), board_ahci },		/* MCP89 */
	{ PCI_VDEVICE(NVIDIA, 0x0d8c), board_ahci },		/* MCP89 */
	{ PCI_VDEVICE(NVIDIA, 0x0d8d), board_ahci },		/* MCP89 */
	{ PCI_VDEVICE(NVIDIA, 0x0d8e), board_ahci },		/* MCP89 */
	{ PCI_VDEVICE(NVIDIA, 0x0d8f), board_ahci },		/* MCP89 */

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

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

	/* Promise */
	{ PCI_VDEVICE(PROMISE, 0x3f20), board_ahci },	/* PDC42819 */

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

	{ }	/* terminate list */
};


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

static int ahci_em_messages = 1;
module_param(ahci_em_messages, int, 0444);
/* add other LED protocol types when they become supported */
MODULE_PARM_DESC(ahci_em_messages,
	"Set AHCI Enclosure Management Message type (0 = disabled, 1 = LED");

#if defined(CONFIG_PATA_MARVELL) || defined(CONFIG_PATA_MARVELL_MODULE)
static int marvell_enable;
#else
static int marvell_enable = 1;
#endif
module_param(marvell_enable, int, 0644);
MODULE_PARM_DESC(marvell_enable, "Marvell SATA via AHCI (1 = enabled)");


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

static inline void __iomem *__ahci_port_base(struct ata_host *host,
					     unsigned int port_no)
{
	struct ahci_host_priv *hpriv = host->private_data;
	void __iomem *mmio = hpriv->mmio;

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

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

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

	/* turn on AHCI_EN */
	tmp = readl(mmio + HOST_CTL);
	if (tmp & HOST_AHCI_EN)
		return;

	/* Some controllers need AHCI_EN to be written multiple times.
	 * Try a few times before giving up.
	 */
	for (i = 0; i < 5; i++) {
		tmp |= HOST_AHCI_EN;
		writel(tmp, mmio + HOST_CTL);
		tmp = readl(mmio + HOST_CTL);	/* flush && sanity check */
		if (tmp & HOST_AHCI_EN)
			return;
		msleep(10);
	}

	WARN_ON(1);
}

static ssize_t ahci_show_host_caps(struct device *dev,
				   struct device_attribute *attr, char *buf)
{
	struct Scsi_Host *shost = class_to_shost(dev);
	struct ata_port *ap = ata_shost_to_port(shost);
	struct ahci_host_priv *hpriv = ap->host->private_data;

	return sprintf(buf, "%x\n", hpriv->cap);
}

static ssize_t ahci_show_host_cap2(struct device *dev,
				   struct device_attribute *attr, char *buf)
{
	struct Scsi_Host *shost = class_to_shost(dev);
	struct ata_port *ap = ata_shost_to_port(shost);
	struct ahci_host_priv *hpriv = ap->host->private_data;

	return sprintf(buf, "%x\n", hpriv->cap2);
}

static ssize_t ahci_show_host_version(struct device *dev,
				   struct device_attribute *attr, char *buf)
{
	struct Scsi_Host *shost = class_to_shost(dev);
	struct ata_port *ap = ata_shost_to_port(shost);
	struct ahci_host_priv *hpriv = ap->host->private_data;
	void __iomem *mmio = hpriv->mmio;

	return sprintf(buf, "%x\n", readl(mmio + HOST_VERSION));
}

static ssize_t ahci_show_port_cmd(struct device *dev,
				  struct device_attribute *attr, char *buf)
{
	struct Scsi_Host *shost = class_to_shost(dev);
	struct ata_port *ap = ata_shost_to_port(shost);
	void __iomem *port_mmio = ahci_port_base(ap);

	return sprintf(buf, "%x\n", readl(port_mmio + PORT_CMD));
}

/**
 *	ahci_save_initial_config - Save and fixup initial config values
 *	@dev: target AHCI device
 *	@hpriv: host private area to store config values
 *	@force_port_map: force port map to a specified value
 *	@mask_port_map: mask out particular bits from port map
 *
 *	Some registers containing configuration info might be setup by
 *	BIOS and might be cleared on reset.  This function saves the
 *	initial values of those registers into @hpriv such that they
 *	can be restored after controller reset.
 *
 *	If inconsistent, config values are fixed up by this function.
 *
 *	LOCKING:
 *	None.
 */
static void ahci_save_initial_config(struct device *dev,
				     struct ahci_host_priv *hpriv,
				     unsigned int force_port_map,
				     unsigned int mask_port_map)
{
	void __iomem *mmio = hpriv->mmio;
	u32 cap, cap2, vers, port_map;
	int i;

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

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

	/* CAP2 register is only defined for AHCI 1.2 and later */
	vers = readl(mmio + HOST_VERSION);
	if ((vers >> 16) > 1 ||
	   ((vers >> 16) == 1 && (vers & 0xFFFF) >= 0x200))
		hpriv->saved_cap2 = cap2 = readl(mmio + HOST_CAP2);
	else
		hpriv->saved_cap2 = cap2 = 0;

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

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

	if (!(cap & HOST_CAP_NCQ) && (hpriv->flags & AHCI_HFLAG_YES_NCQ)) {
		dev_printk(KERN_INFO, dev,
			   "controller can do NCQ, turning on CAP_NCQ\n");
		cap |= HOST_CAP_NCQ;
	}

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

	if ((cap & HOST_CAP_SNTF) && (hpriv->flags & AHCI_HFLAG_NO_SNTF)) {
		dev_printk(KERN_INFO, dev,
			   "controller can't do SNTF, turning off CAP_SNTF\n");
		cap &= ~HOST_CAP_SNTF;
	}

	if (force_port_map && port_map != force_port_map) {
		dev_printk(KERN_INFO, dev, "forcing port_map 0x%x -> 0x%x\n",
			   port_map, force_port_map);
		port_map = force_port_map;
	}

	if (mask_port_map) {
		dev_printk(KERN_ERR, dev, "masking port_map 0x%x -> 0x%x\n",
			   port_map,
			   port_map & mask_port_map);
		port_map &= mask_port_map;
	}

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

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

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

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

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

	/* record values to use during operation */
	hpriv->cap = cap;
	hpriv->cap2 = cap2;
	hpriv->port_map = port_map;
}

static void ahci_pci_save_initial_config(struct pci_dev *pdev,
					 struct ahci_host_priv *hpriv)
{
	unsigned int force_port_map = 0;
	unsigned int mask_port_map = 0;

	if (pdev->vendor == PCI_VENDOR_ID_JMICRON && pdev->device == 0x2361) {
		dev_info(&pdev->dev, "JMB361 has only one port\n");
		force_port_map = 1;
	}

	/*
	 * Temporary Marvell 6145 hack: PATA port presence
	 * is asserted through the standard AHCI port
	 * presence register, as bit 4 (counting from 0)
	 */
	if (hpriv->flags & AHCI_HFLAG_MV_PATA) {
		if (pdev->device == 0x6121)
			mask_port_map = 0x3;
		else
			mask_port_map = 0xf;
		dev_info(&pdev->dev,
			  "Disabling your PATA port. Use the boot option 'ahci.marvell_enable=0' to avoid this.\n");
	}

	ahci_save_initial_config(&pdev->dev, hpriv, force_port_map,
				 mask_port_map);
}

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

	writel(hpriv->saved_cap, mmio + HOST_CAP);
	if (hpriv->saved_cap2)
		writel(hpriv->saved_cap2, mmio + HOST_CAP2);
	writel(hpriv->saved_port_map, mmio + HOST_PORTS_IMPL);
	(void) readl(mmio + HOST_PORTS_IMPL);	/* flush */
}

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

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

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

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

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

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

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

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

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

	tmp = readl(port_mmio + PORT_CMD);

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

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

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

	return 0;
}

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

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

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

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

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

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

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

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

	return 0;
}

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

static void ahci_start_port(struct ata_port *ap)
{
	struct ahci_port_priv *pp = ap->private_data;
	struct ata_link *link;
	struct ahci_em_priv *emp;
	ssize_t rc;
	int i;

	/* enable FIS reception */
	ahci_start_fis_rx(ap);

	/* enable DMA */
	ahci_start_engine(ap);

	/* turn on LEDs */
	if (ap->flags & ATA_FLAG_EM) {
		ata_for_each_link(link, ap, EDGE) {
			emp = &pp->em_priv[link->pmp];

			/* EM Transmit bit maybe busy during init */
			for (i = 0; i < EM_MAX_RETRY; i++) {
				rc = ahci_transmit_led_message(ap,
							       emp->led_state,
							       4);
				if (rc == -EBUSY)
					msleep(1);
				else
					break;
			}
		}
	}

	if (ap->flags & ATA_FLAG_SW_ACTIVITY)
		ata_for_each_link(link, ap, EDGE)
			ahci_init_sw_activity(link);

}

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

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

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

	return 0;
}

static int ahci_reset_controller(struct ata_host *host)
{
	struct ahci_host_priv *hpriv = host->private_data;
	void __iomem *mmio = hpriv->mmio;
	u32 tmp;

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

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

		/*
		 * to perform host reset, OS should set HOST_RESET
		 * and poll until this bit is read to be "0".
		 * reset must complete within 1 second, or
		 * the hardware should be considered fried.
		 */
		tmp = ata_wait_register(mmio + HOST_CTL, HOST_RESET,
					HOST_RESET, 10, 1000);

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

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

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

	return 0;
}

static int ahci_pci_reset_controller(struct ata_host *host)
{
	struct pci_dev *pdev = to_pci_dev(host->dev);

	ahci_reset_controller(host);

	if (pdev->vendor == PCI_VENDOR_ID_INTEL) {
		struct ahci_host_priv *hpriv = host->private_data;
		u16 tmp16;

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

	return 0;
}

static void ahci_sw_activity(struct ata_link *link)
{
	struct ata_port *ap = link->ap;
	struct ahci_port_priv *pp = ap->private_data;
	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];

	if (!(link->flags & ATA_LFLAG_SW_ACTIVITY))
		return;

	emp->activity++;
	if (!timer_pending(&emp->timer))
		mod_timer(&emp->timer, jiffies + msecs_to_jiffies(10));
}

static void ahci_sw_activity_blink(unsigned long arg)
{
	struct ata_link *link = (struct ata_link *)arg;
	struct ata_port *ap = link->ap;
	struct ahci_port_priv *pp = ap->private_data;
	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
	unsigned long led_message = emp->led_state;
	u32 activity_led_state;
	unsigned long flags;

	led_message &= EM_MSG_LED_VALUE;
	led_message |= ap->port_no | (link->pmp << 8);

	/* check to see if we've had activity.  If so,
	 * toggle state of LED and reset timer.  If not,
	 * turn LED to desired idle state.
	 */
	spin_lock_irqsave(ap->lock, flags);
	if (emp->saved_activity != emp->activity) {
		emp->saved_activity = emp->activity;
		/* get the current LED state */
		activity_led_state = led_message & EM_MSG_LED_VALUE_ON;

		if (activity_led_state)
			activity_led_state = 0;
		else
			activity_led_state = 1;

		/* clear old state */
		led_message &= ~EM_MSG_LED_VALUE_ACTIVITY;

		/* toggle state */
		led_message |= (activity_led_state << 16);
		mod_timer(&emp->timer, jiffies + msecs_to_jiffies(100));
	} else {
		/* switch to idle */
		led_message &= ~EM_MSG_LED_VALUE_ACTIVITY;
		if (emp->blink_policy == BLINK_OFF)
			led_message |= (1 << 16);
	}
	spin_unlock_irqrestore(ap->lock, flags);
	ahci_transmit_led_message(ap, led_message, 4);
}

static void ahci_init_sw_activity(struct ata_link *link)
{
	struct ata_port *ap = link->ap;
	struct ahci_port_priv *pp = ap->private_data;
	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];

	/* init activity stats, setup timer */
	emp->saved_activity = emp->activity = 0;
	setup_timer(&emp->timer, ahci_sw_activity_blink, (unsigned long)link);

	/* check our blink policy and set flag for link if it's enabled */
	if (emp->blink_policy)
		link->flags |= ATA_LFLAG_SW_ACTIVITY;
}

static int ahci_reset_em(struct ata_host *host)
{
	struct ahci_host_priv *hpriv = host->private_data;
	void __iomem *mmio = hpriv->mmio;
	u32 em_ctl;

	em_ctl = readl(mmio + HOST_EM_CTL);
	if ((em_ctl & EM_CTL_TM) || (em_ctl & EM_CTL_RST))
		return -EINVAL;

	writel(em_ctl | EM_CTL_RST, mmio + HOST_EM_CTL);
	return 0;
}

static ssize_t ahci_transmit_led_message(struct ata_port *ap, u32 state,
					ssize_t size)
{
	struct ahci_host_priv *hpriv = ap->host->private_data;
	struct ahci_port_priv *pp = ap->private_data;
	void __iomem *mmio = hpriv->mmio;
	u32 em_ctl;
	u32 message[] = {0, 0};
	unsigned long flags;
	int pmp;
	struct ahci_em_priv *emp;

	/* get the slot number from the message */
	pmp = (state & EM_MSG_LED_PMP_SLOT) >> 8;
	if (pmp < EM_MAX_SLOTS)
		emp = &pp->em_priv[pmp];
	else
		return -EINVAL;

	spin_lock_irqsave(ap->lock, flags);

	/*
	 * if we are still busy transmitting a previous message,
	 * do not allow
	 */
	em_ctl = readl(mmio + HOST_EM_CTL);
	if (em_ctl & EM_CTL_TM) {
		spin_unlock_irqrestore(ap->lock, flags);
		return -EBUSY;
	}

	/*
	 * create message header - this is all zero except for
	 * the message size, which is 4 bytes.
	 */
	message[0] |= (4 << 8);

	/* ignore 0:4 of byte zero, fill in port info yourself */
	message[1] = ((state & ~EM_MSG_LED_HBA_PORT) | ap->port_no);

	/* write message to EM_LOC */
	writel(message[0], mmio + hpriv->em_loc);
	writel(message[1], mmio + hpriv->em_loc+4);

	/* save off new led state for port/slot */
	emp->led_state = state;

	/*
	 * tell hardware to transmit the message
	 */
	writel(em_ctl | EM_CTL_TM, mmio + HOST_EM_CTL);

	spin_unlock_irqrestore(ap->lock, flags);
	return size;
}

static ssize_t ahci_led_show(struct ata_port *ap, char *buf)
{
	struct ahci_port_priv *pp = ap->private_data;
	struct ata_link *link;
	struct ahci_em_priv *emp;
	int rc = 0;

	ata_for_each_link(link, ap, EDGE) {
		emp = &pp->em_priv[link->pmp];
		rc += sprintf(buf, "%lx\n", emp->led_state);
	}
	return rc;
}

static ssize_t ahci_led_store(struct ata_port *ap, const char *buf,
				size_t size)
{
	int state;
	int pmp;
	struct ahci_port_priv *pp = ap->private_data;
	struct ahci_em_priv *emp;

	state = simple_strtoul(buf, NULL, 0);

	/* get the slot number from the message */
	pmp = (state & EM_MSG_LED_PMP_SLOT) >> 8;
	if (pmp < EM_MAX_SLOTS)
		emp = &pp->em_priv[pmp];
	else
		return -EINVAL;

	/* mask off the activity bits if we are in sw_activity
	 * mode, user should turn off sw_activity before setting
	 * activity led through em_message
	 */
	if (emp->blink_policy)
		state &= ~EM_MSG_LED_VALUE_ACTIVITY;

	return ahci_transmit_led_message(ap, state, size);
}

static ssize_t ahci_activity_store(struct ata_device *dev, enum sw_activity val)
{
	struct ata_link *link = dev->link;
	struct ata_port *ap = link->ap;
	struct ahci_port_priv *pp = ap->private_data;
	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];
	u32 port_led_state = emp->led_state;

	/* save the desired Activity LED behavior */
	if (val == OFF) {
		/* clear LFLAG */
		link->flags &= ~(ATA_LFLAG_SW_ACTIVITY);

		/* set the LED to OFF */
		port_led_state &= EM_MSG_LED_VALUE_OFF;
		port_led_state |= (ap->port_no | (link->pmp << 8));
		ahci_transmit_led_message(ap, port_led_state, 4);
	} else {
		link->flags |= ATA_LFLAG_SW_ACTIVITY;
		if (val == BLINK_OFF) {
			/* set LED to ON for idle */
			port_led_state &= EM_MSG_LED_VALUE_OFF;
			port_led_state |= (ap->port_no | (link->pmp << 8));
			port_led_state |= EM_MSG_LED_VALUE_ON; /* check this */
			ahci_transmit_led_message(ap, port_led_state, 4);
		}
	}
	emp->blink_policy = val;
	return 0;
}

static ssize_t ahci_activity_show(struct ata_device *dev, char *buf)
{
	struct ata_link *link = dev->link;
	struct ata_port *ap = link->ap;
	struct ahci_port_priv *pp = ap->private_data;
	struct ahci_em_priv *emp = &pp->em_priv[link->pmp];

	/* display the saved value of activity behavior for this
	 * disk.
	 */
	return sprintf(buf, "%d\n", emp->blink_policy);
}

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

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

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

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

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

static void ahci_init_controller(struct ata_host *host)
{
	struct ahci_host_priv *hpriv = host->private_data;
	void __iomem *mmio = hpriv->mmio;
	int i;
	void __iomem *port_mmio;
	u32 tmp;

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

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

		ahci_port_init(host->dev, ap, i, mmio, port_mmio);
	}

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

static void ahci_pci_init_controller(struct ata_host *host)
{
	struct ahci_host_priv *hpriv = host->private_data;
	struct pci_dev *pdev = to_pci_dev(host->dev);
	void __iomem *port_mmio;
	u32 tmp;
	int mv;

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

		writel(0, port_mmio + PORT_IRQ_MASK);

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

	ahci_init_controller(host);
}

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

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

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

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

	return ata_dev_classify(&tf);
}

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

	cmd_tbl_dma = pp->cmd_tbl_dma + tag * AHCI_CMD_TBL_SZ;

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

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

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

	/* need to do CLO?
	 * always do CLO if PMP is attached (AHCI-1.3 9.2)
	 */
	busy = status & (ATA_BUSY | ATA_DRQ);
	if (!busy && !sata_pmp_attached(ap)) {
		rc = 0;
		goto out_restart;
	}

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

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

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

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

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

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

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

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

	return 0;
}

static int ahci_do_softreset(struct ata_link *link, unsigned int *class,
			     int pmp, unsigned long deadline,
			     int (*check_ready)(struct ata_link *link))
{
	struct ata_port *ap = link->ap;
	struct ahci_host_priv *hpriv = ap->host->private_data;
	const char *reason = NULL;
	unsigned long now, msecs;
	struct ata_taskfile tf;
	int rc;

	DPRINTK("ENTER\n");

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

	ata_tf_init(link->device, &tf);

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

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

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

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

	/* wait for link to become ready */
	rc = ata_wait_after_reset(link, deadline, check_ready);
	if (rc == -EBUSY && hpriv->flags & AHCI_HFLAG_SRST_TOUT_IS_OFFLINE) {
		/*
		 * Workaround for cases where link online status can't
		 * be trusted.  Treat device readiness timeout as link
		 * offline.
		 */
		ata_link_printk(link, KERN_INFO,
				"device not ready, treating as offline\n");
		*class = ATA_DEV_NONE;
	} else if (rc) {
		/* link occupied, -ENODEV too is an error */
		reason = "device not ready";
		goto fail;
	} else
		*class = ahci_dev_classify(ap);

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

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

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

	return ata_check_ready(status);
}

static int ahci_softreset(struct ata_link *link, unsigned int *class,
			  unsigned long deadline)
{
	int pmp = sata_srst_pmp(link);

	DPRINTK("ENTER\n");

	return ahci_do_softreset(link, class, pmp, deadline, ahci_check_ready);
}

static int ahci_sb600_check_ready(struct ata_link *link)
{
	void __iomem *port_mmio = ahci_port_base(link->ap);
	u8 status = readl(port_mmio + PORT_TFDATA) & 0xFF;
	u32 irq_status = readl(port_mmio + PORT_IRQ_STAT);

	/*
	 * There is no need to check TFDATA if BAD PMP is found due to HW bug,
	 * which can save timeout delay.
	 */
	if (irq_status & PORT_IRQ_BAD_PMP)
		return -EIO;

	return ata_check_ready(status);
}

static int ahci_sb600_softreset(struct ata_link *link, unsigned int *class,
				unsigned long deadline)
{
	struct ata_port *ap = link->ap;
	void __iomem *port_mmio = ahci_port_base(ap);
	int pmp = sata_srst_pmp(link);
	int rc;
	u32 irq_sts;

	DPRINTK("ENTER\n");

	rc = ahci_do_softreset(link, class, pmp, deadline,
			       ahci_sb600_check_ready);

	/*
	 * Soft reset fails on some ATI chips with IPMS set when PMP
	 * is enabled but SATA HDD/ODD is connected to SATA port,
	 * do soft reset again to port 0.
	 */
	if (rc == -EIO) {
		irq_sts = readl(port_mmio + PORT_IRQ_STAT);
		if (irq_sts & PORT_IRQ_BAD_PMP) {
			ata_link_printk(link, KERN_WARNING,
					"applying SB600 PMP SRST workaround "
					"and retrying\n");
			rc = ahci_do_softreset(link, class, 0, deadline,
					       ahci_check_ready);
		}
	}

	return rc;
}

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

	DPRINTK("ENTER\n");

	ahci_stop_engine(ap);

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

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

	ahci_start_engine(ap);

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

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

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

	DPRINTK("ENTER\n");

	ahci_stop_engine(ap);

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

	ahci_start_engine(ap);

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

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

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

	ahci_stop_engine(ap);

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

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

	ahci_start_engine(ap);

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

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

	ata_std_postreset(link, class);

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

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

	VPRINTK("ENTER\n");

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

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

	return si;
}

static int ahci_pmp_qc_defer(struct ata_queued_cmd *qc)
{
	struct ata_port *ap = qc->ap;
	struct ahci_port_priv *pp = ap->private_data;

	if (!sata_pmp_attached(ap) || pp->fbs_enabled)
		return ata_std_qc_defer(qc);
	else
		return sata_pmp_qc_defer_cmd_switch(qc);
}

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

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

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

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

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

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

static void ahci_fbs_dec_intr(struct ata_port *ap)
{
	struct ahci_port_priv *pp = ap->private_data;
	void __iomem *port_mmio = ahci_port_base(ap);
	u32 fbs = readl(port_mmio + PORT_FBS);
	int retries = 3;

	DPRINTK("ENTER\n");
	BUG_ON(!pp->fbs_enabled);

	/* time to wait for DEC is not specified by AHCI spec,
	 * add a retry loop for safety.
	 */
	writel(fbs | PORT_FBS_DEC, port_mmio + PORT_FBS);
	fbs = readl(port_mmio + PORT_FBS);
	while ((fbs & PORT_FBS_DEC) && retries--) {
		udelay(1);
		fbs = readl(port_mmio + PORT_FBS);
	}

	if (fbs & PORT_FBS_DEC)
		dev_printk(KERN_ERR, ap->host->dev,
			   "failed to clear device error\n");
}

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

	/* determine active link with error */
	if (pp->fbs_enabled) {
		void __iomem *port_mmio = ahci_port_base(ap);
		u32 fbs = readl(port_mmio + PORT_FBS);
		int pmp = fbs >> PORT_FBS_DWE_OFFSET;

		if ((fbs & PORT_FBS_SDE) && (pmp < ap->nr_pmp_links) &&
		    ata_link_online(&ap->pmp_link[pmp])) {
			link = &ap->pmp_link[pmp];
			fbs_need_dec = true;
		}

	} else
		ata_for_each_link(link, ap, EDGE)
			if (ata_link_active(link))
				break;

	if (!link)
		link = &ap->link;

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

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

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

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

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

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

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

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

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

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

	if (irq_stat & PORT_IRQ_IF_ERR) {
		if (fbs_need_dec)
			active_ehi->err_mask |= AC_ERR_DEV;
		else {
			host_ehi->err_mask |= AC_ERR_ATA_BUS;
			host_ehi->action |= ATA_EH_RESET;
		}

		ata_ehi_push_desc(host_ehi, "interface fatal error");
	}

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

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

	if (irq_stat & PORT_IRQ_FREEZE)
		ata_port_freeze(ap);
	else if (fbs_need_dec) {
		ata_link_abort(link);
		ahci_fbs_dec_intr(ap);
	} else
		ata_port_abort(ap);
}

static void ahci_port_intr(struct ata_port *ap)
{
	void __iomem *port_mmio = ahci_port_base(ap);
	struct ata_eh_info *ehi = &ap->link.eh_info;
	struct ahci_port_priv *pp = ap->private_data;
	struct ahci_host_priv *hpriv = ap->host->private_data;
	int resetting = !!(ap->pflags & ATA_PFLAG_RESETTING);
	u32 status, qc_active = 0;
	int rc;

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

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

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

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

	if (status & PORT_IRQ_SDB_FIS) {
		/* If SNotification is available, leave notification
		 * handling to sata_async_notification().  If not,
		 * emulate it by snooping SDB FIS RX area.
		 *
		 * Snooping FIS RX area is probably cheaper than
		 * poking SNotification but some constrollers which
		 * implement SNotification, ICH9 for example, don't
		 * store AN SDB FIS into receive area.
		 */
		if (hpriv->cap & HOST_CAP_SNTF)
			sata_async_notification(ap);
		else {
			/* If the 'N' bit in word 0 of the FIS is set,
			 * we just received asynchronous notification.
			 * Tell libata about it.
			 *
			 * Lack of SNotification should not appear in
			 * ahci 1.2, so the workaround is unnecessary
			 * when FBS is enabled.
			 */
			if (pp->fbs_enabled)
				WARN_ON_ONCE(1);
			else {
				const __le32 *f = pp->rx_fis + RX_FIS_SDB;
				u32 f0 = le32_to_cpu(f[0]);
				if (f0 & (1 << 15))
					sata_async_notification(ap);
			}
		}
	}

	/* pp->active_link is not reliable once FBS is enabled, both
	 * PORT_SCR_ACT and PORT_CMD_ISSUE should be checked because
	 * NCQ and non-NCQ commands may be in flight at the same time.
	 */
	if (pp->fbs_enabled) {
		if (ap->qc_active) {
			qc_active = readl(port_mmio + PORT_SCR_ACT);
			qc_active |= readl(port_mmio + PORT_CMD_ISSUE);
		}
	} else {
		/* pp->active_link is valid iff any command is in flight */
		if (ap->qc_active && pp->active_link->sactive)
			qc_active = readl(port_mmio + PORT_SCR_ACT);
		else
			qc_active = readl(port_mmio + PORT_CMD_ISSUE);
	}

	rc = ata_qc_complete_multiple(ap, qc_active);

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

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

	VPRINTK("ENTER\n");

	hpriv = host->private_data;
	mmio = hpriv->mmio;

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

	irq_masked = irq_stat & hpriv->port_map;

	spin_lock(&host->lock);

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

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

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

		handled = 1;
	}

	/* HOST_IRQ_STAT behaves as level triggered latch meaning that
	 * it should be cleared after all the port events are cleared;
	 * otherwise, it will raise a spurious interrupt after each
	 * valid one.  Please read section 10.6.2 of ahci 1.1 for more
	 * information.
	 *
	 * Also, use the unmasked value to clear interrupt as spurious
	 * pending event on a dummy port might cause screaming IRQ.
	 */
	writel(irq_stat, mmio + HOST_IRQ_STAT);

	spin_unlock(&host->lock);

	VPRINTK("EXIT\n");

	return IRQ_RETVAL(handled);
}

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

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

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

	if (pp->fbs_enabled && pp->fbs_last_dev != qc->dev->link->pmp) {
		u32 fbs = readl(port_mmio + PORT_FBS);
		fbs &= ~(PORT_FBS_DEV_MASK | PORT_FBS_DEC);
		fbs |= qc->dev->link->pmp << PORT_FBS_DEV_OFFSET;
		writel(fbs, port_mmio + PORT_FBS);
		pp->fbs_last_dev = qc->dev->link->pmp;
	}

	writel(1 << qc->tag, port_mmio + PORT_CMD_ISSUE);

	ahci_sw_activity(qc->dev->link);

	return 0;
}

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

	if (pp->fbs_enabled)
		d2h_fis += qc->dev->link->pmp * AHCI_RX_FIS_SZ;

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

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

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

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

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

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

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

	sata_pmp_error_handler(ap);
}

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

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

static void ahci_enable_fbs(struct ata_port *ap)
{
	struct ahci_port_priv *pp = ap->private_data;
	void __iomem *port_mmio = ahci_port_base(ap);
	u32 fbs;
	int rc;

	if (!pp->fbs_supported)
		return;

	fbs = readl(port_mmio + PORT_FBS);
	if (fbs & PORT_FBS_EN) {
		pp->fbs_enabled = true;
		pp->fbs_last_dev = -1; /* initialization */
		return;
	}

	rc = ahci_stop_engine(ap);
	if (rc)
		return;

	writel(fbs | PORT_FBS_EN, port_mmio + PORT_FBS);
	fbs = readl(port_mmio + PORT_FBS);
	if (fbs & PORT_FBS_EN) {
		dev_printk(KERN_INFO, ap->host->dev, "FBS is enabled.\n");
		pp->fbs_enabled = true;
		pp->fbs_last_dev = -1; /* initialization */
	} else
		dev_printk(KERN_ERR, ap->host->dev, "Failed to enable FBS\n");

	ahci_start_engine(ap);
}

static void ahci_disable_fbs(struct ata_port *ap)
{
	struct ahci_port_priv *pp = ap->private_data;
	void __iomem *port_mmio = ahci_port_base(ap);
	u32 fbs;
	int rc;

	if (!pp->fbs_supported)
		return;

	fbs = readl(port_mmio + PORT_FBS);
	if ((fbs & PORT_FBS_EN) == 0) {
		pp->fbs_enabled = false;
		return;
	}

	rc = ahci_stop_engine(ap);
	if (rc)
		return;

	writel(fbs & ~PORT_FBS_EN, port_mmio + PORT_FBS);
	fbs = readl(port_mmio + PORT_FBS);
	if (fbs & PORT_FBS_EN)
		dev_printk(KERN_ERR, ap->host->dev, "Failed to disable FBS\n");
	else {
		dev_printk(KERN_INFO, ap->host->dev, "FBS is disabled.\n");
		pp->fbs_enabled = false;
	}

	ahci_start_engine(ap);
}

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

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

	ahci_enable_fbs(ap);

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

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

	ahci_disable_fbs(ap);

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

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

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

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

	return 0;
}

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

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

	return rc;
}

static int ahci_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg)
{
	struct ata_host *host = dev_get_drvdata(&pdev->dev);
	struct ahci_host_priv *hpriv = host->private_data;
	void __iomem *mmio = hpriv->mmio;
	u32 ctl;

	if (mesg.event & PM_EVENT_SUSPEND &&
	    hpriv->flags & AHCI_HFLAG_NO_SUSPEND) {
		dev_printk(KERN_ERR, &pdev->dev,
			   "BIOS update required for suspend/resume\n");
		return -EIO;
	}

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

	return ata_pci_device_suspend(pdev, mesg);
}

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

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

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

		ahci_pci_init_controller(host);
	}

	ata_host_resume(host);

	return 0;
}
#endif

static int ahci_port_start(struct ata_port *ap)
{
	struct ahci_host_priv *hpriv = ap->host->private_data;
	struct device *dev = ap->host->dev;
	struct ahci_port_priv *pp;
	void *mem;
	dma_addr_t mem_dma;
	size_t dma_sz, rx_fis_sz;

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

	/* check FBS capability */
	if ((hpriv->cap & HOST_CAP_FBS) && sata_pmp_supported(ap)) {
		void __iomem *port_mmio = ahci_port_base(ap);
		u32 cmd = readl(port_mmio + PORT_CMD);
		if (cmd & PORT_CMD_FBSCP)
			pp->fbs_supported = true;
		else
			dev_printk(KERN_WARNING, dev,
				   "The port is not capable of FBS\n");
	}

	if (pp->fbs_supported) {
		dma_sz = AHCI_PORT_PRIV_FBS_DMA_SZ;
		rx_fis_sz = AHCI_RX_FIS_SZ * 16;
	} else {
		dma_sz = AHCI_PORT_PRIV_DMA_SZ;
		rx_fis_sz = AHCI_RX_FIS_SZ;
	}

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

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

	mem += AHCI_CMD_SLOT_SZ;
	mem_dma += AHCI_CMD_SLOT_SZ;

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

	mem += rx_fis_sz;
	mem_dma += rx_fis_sz;

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

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

	ap->private_data = pp;

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

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

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

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

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

static void ahci_print_info(struct ata_host *host)
{
	struct ahci_host_priv *hpriv = host->private_data;
	struct pci_dev *pdev = to_pci_dev(host->dev);
	void __iomem *mmio = hpriv->mmio;
	u32 vers, cap, cap2, impl, speed;
	const char *speed_s;
	u16 cc;
	const char *scc_s;

	vers = readl(mmio + HOST_VERSION);
	cap = hpriv->cap;
	cap2 = hpriv->cap2;
	impl = hpriv->port_map;

	speed = (cap >> 20) & 0xf;
	if (speed == 1)
		speed_s = "1.5";
	else if (speed == 2)
		speed_s = "3";
	else if (speed == 3)
		speed_s = "6";
	else
		speed_s = "?";

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

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

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

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

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

		cap & HOST_CAP_64 ? "64bit " : "",
		cap & HOST_CAP_NCQ ? "ncq " : "",
		cap & HOST_CAP_SNTF ? "sntf " : "",
		cap & HOST_CAP_MPS ? "ilck " : "",
		cap & HOST_CAP_SSS ? "stag " : "",
		cap & HOST_CAP_ALPM ? "pm " : "",
		cap & HOST_CAP_LED ? "led " : "",
		cap & HOST_CAP_CLO ? "clo " : "",
		cap & HOST_CAP_ONLY ? "only " : "",
		cap & HOST_CAP_PMP ? "pmp " : "",
		cap & HOST_CAP_FBS ? "fbs " : "",
		cap & HOST_CAP_PIO_MULTI ? "pio " : "",
		cap & HOST_CAP_SSC ? "slum " : "",
		cap & HOST_CAP_PART ? "part " : "",
		cap & HOST_CAP_CCC ? "ccc " : "",
		cap & HOST_CAP_EMS ? "ems " : "",
		cap & HOST_CAP_SXS ? "sxs " : "",
		cap2 & HOST_CAP2_APST ? "apst " : "",
		cap2 & HOST_CAP2_NVMHCI ? "nvmp " : "",
		cap2 & HOST_CAP2_BOH ? "boh " : ""
		);
}

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

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

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

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

/* only some SB600 ahci controllers can do 64bit DMA */
static bool ahci_sb600_enable_64bit(struct pci_dev *pdev)
{
	static const struct dmi_system_id sysids[] = {
		/*
		 * The oldest version known to be broken is 0901 and
		 * working is 1501 which was released on 2007-10-26.
		 * Enable 64bit DMA on 1501 and anything newer.
		 *
		 * Please read bko#9412 for more info.
		 */
		{
			.ident = "ASUS M2A-VM",
			.matches = {
				DMI_MATCH(DMI_BOARD_VENDOR,
					  "ASUSTeK Computer INC."),
				DMI_MATCH(DMI_BOARD_NAME, "M2A-VM"),
			},
			.driver_data = "20071026",	/* yyyymmdd */
		},
		/*
		 * All BIOS versions for the MSI K9A2 Platinum (MS-7376)
		 * support 64bit DMA.
		 *
		 * BIOS versions earlier than 1.5 had the Manufacturer DMI
		 * fields as "MICRO-STAR INTERANTIONAL CO.,LTD".
		 * This spelling mistake was fixed in BIOS version 1.5, so
		 * 1.5 and later have the Manufacturer as
		 * "MICRO-STAR INTERNATIONAL CO.,LTD".
		 * So try to match on DMI_BOARD_VENDOR of "MICRO-STAR INTER".
		 *
		 * BIOS versions earlier than 1.9 had a Board Product Name
		 * DMI field of "MS-7376". This was changed to be
		 * "K9A2 Platinum (MS-7376)" in version 1.9, but we can still
		 * match on DMI_BOARD_NAME of "MS-7376".
		 */
		{
			.ident = "MSI K9A2 Platinum",
			.matches = {
				DMI_MATCH(DMI_BOARD_VENDOR,
					  "MICRO-STAR INTER"),
				DMI_MATCH(DMI_BOARD_NAME, "MS-7376"),
			},
		},
		{ }
	};
	const struct dmi_system_id *match;
	int year, month, date;
	char buf[9];

	match = dmi_first_match(sysids);
	if (pdev->bus->number != 0 || pdev->devfn != PCI_DEVFN(0x12, 0) ||
	    !match)
		return false;

	if (!match->driver_data)
		goto enable_64bit;

	dmi_get_date(DMI_BIOS_DATE, &year, &month, &date);
	snprintf(buf, sizeof(buf), "%04d%02d%02d", year, month, date);

	if (strcmp(buf, match->driver_data) >= 0)
		goto enable_64bit;
	else {
		dev_printk(KERN_WARNING, &pdev->dev, "%s: BIOS too old, "
			   "forcing 32bit DMA, update BIOS\n", match->ident);
		return false;
	}

enable_64bit:
	dev_printk(KERN_WARNING, &pdev->dev, "%s: enabling 64bit DMA\n",
		   match->ident);
	return true;
}

static bool ahci_broken_system_poweroff(struct pci_dev *pdev)
{
	static const struct dmi_system_id broken_systems[] = {
		{
			.ident = "HP Compaq nx6310",
			.matches = {
				DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
				DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq nx6310"),
			},
			/* PCI slot number of the controller */
			.driver_data = (void *)0x1FUL,
		},
		{
			.ident = "HP Compaq 6720s",
			.matches = {
				DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
				DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq 6720s"),
			},
			/* PCI slot number of the controller */
			.driver_data = (void *)0x1FUL,
		},

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

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

	return false;
}

static bool ahci_broken_suspend(struct pci_dev *pdev)
{
	static const struct dmi_system_id sysids[] = {
		/*
		 * On HP dv[4-6] and HDX18 with earlier BIOSen, link
		 * to the harddisk doesn't become online after
		 * resuming from STR.  Warn and fail suspend.
		 *
		 * http://bugzilla.kernel.org/show_bug.cgi?id=12276
		 *
		 * Use dates instead of versions to match as HP is
		 * apparently recycling both product and version
		 * strings.
		 *
		 * http://bugzilla.kernel.org/show_bug.cgi?id=15462
		 */
		{
			.ident = "dv4",
			.matches = {
				DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
				DMI_MATCH(DMI_PRODUCT_NAME,
					  "HP Pavilion dv4 Notebook PC"),
			},
			.driver_data = "20090105",	/* F.30 */
		},
		{
			.ident = "dv5",
			.matches = {
				DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
				DMI_MATCH(DMI_PRODUCT_NAME,
					  "HP Pavilion dv5 Notebook PC"),
			},
			.driver_data = "20090506",	/* F.16 */
		},
		{
			.ident = "dv6",
			.matches = {
				DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
				DMI_MATCH(DMI_PRODUCT_NAME,
					  "HP Pavilion dv6 Notebook PC"),
			},
			.driver_data = "20090423",	/* F.21 */
		},
		{
			.ident = "HDX18",
			.matches = {
				DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
				DMI_MATCH(DMI_PRODUCT_NAME,
					  "HP HDX18 Notebook PC"),
			},
			.driver_data = "20090430",	/* F.23 */
		},
		/*
		 * Acer eMachines G725 has the same problem.  BIOS
		 * V1.03 is known to be broken.  V3.04 is known to
		 * work.  Inbetween, there are V1.06, V2.06 and V3.03
		 * that we don't have much idea about.  For now,
		 * blacklist anything older than V3.04.
		 *
		 * http://bugzilla.kernel.org/show_bug.cgi?id=15104
		 */
		{
			.ident = "G725",
			.matches = {
				DMI_MATCH(DMI_SYS_VENDOR, "eMachines"),
				DMI_MATCH(DMI_PRODUCT_NAME, "eMachines G725"),
			},
			.driver_data = "20091216",	/* V3.04 */
		},
		{ }	/* terminate list */
	};
	const struct dmi_system_id *dmi = dmi_first_match(sysids);
	int year, month, date;
	char buf[9];

	if (!dmi || pdev->bus->number || pdev->devfn != PCI_DEVFN(0x1f, 2))
		return false;

	dmi_get_date(DMI_BIOS_DATE, &year, &month, &date);
	snprintf(buf, sizeof(buf), "%04d%02d%02d", year, month, date);

	return strcmp(buf, dmi->driver_data) < 0;
}

static bool ahci_broken_online(struct pci_dev *pdev)
{
#define ENCODE_BUSDEVFN(bus, slot, func)			\
	(void *)(unsigned long)(((bus) << 8) | PCI_DEVFN((slot), (func)))
	static const struct dmi_system_id sysids[] = {
		/*
		 * There are several gigabyte boards which use
		 * SIMG5723s configured as hardware RAID.  Certain
		 * 5723 firmware revisions shipped there keep the link
		 * online but fail to answer properly to SRST or
		 * IDENTIFY when no device is attached downstream
		 * causing libata to retry quite a few times leading
		 * to excessive detection delay.
		 *
		 * As these firmwares respond to the second reset try
		 * with invalid device signature, considering unknown
		 * sig as offline works around the problem acceptably.
		 */
		{
			.ident = "EP45-DQ6",
			.matches = {
				DMI_MATCH(DMI_BOARD_VENDOR,
					  "Gigabyte Technology Co., Ltd."),
				DMI_MATCH(DMI_BOARD_NAME, "EP45-DQ6"),
			},
			.driver_data = ENCODE_BUSDEVFN(0x0a, 0x00, 0),
		},
		{
			.ident = "EP45-DS5",
			.matches = {
				DMI_MATCH(DMI_BOARD_VENDOR,
					  "Gigabyte Technology Co., Ltd."),
				DMI_MATCH(DMI_BOARD_NAME, "EP45-DS5"),
			},
			.driver_data = ENCODE_BUSDEVFN(0x03, 0x00, 0),
		},
		{ }	/* terminate list */
	};
#undef ENCODE_BUSDEVFN
	const struct dmi_system_id *dmi = dmi_first_match(sysids);
	unsigned int val;

	if (!dmi)
		return false;

	val = (unsigned long)dmi->driver_data;

	return pdev->bus->number == (val >> 8) && pdev->devfn == (val & 0xff);
}

#ifdef CONFIG_ATA_ACPI
static void ahci_gtf_filter_workaround(struct ata_host *host)
{
	static const struct dmi_system_id sysids[] = {
		/*
		 * Aspire 3810T issues a bunch of SATA enable commands
		 * via _GTF including an invalid one and one which is
		 * rejected by the device.  Among the successful ones
		 * is FPDMA non-zero offset enable which when enabled
		 * only on the drive side leads to NCQ command
		 * failures.  Filter it out.
		 */
		{
			.ident = "Aspire 3810T",
			.matches = {
				DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
				DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 3810T"),
			},
			.driver_data = (void *)ATA_ACPI_FILTER_FPDMA_OFFSET,
		},
		{ }
	};
	const struct dmi_system_id *dmi = dmi_first_match(sysids);
	unsigned int filter;
	int i;

	if (!dmi)
		return;

	filter = (unsigned long)dmi->driver_data;
	dev_printk(KERN_INFO, host->dev,
		   "applying extra ACPI _GTF filter 0x%x for %s\n",
		   filter, dmi->ident);

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

		ata_for_each_link(link, ap, EDGE)
			ata_for_each_dev(dev, link, ALL)
				dev->gtf_filter |= filter;
	}
}
#else
static inline void ahci_gtf_filter_workaround(struct ata_host *host)
{}
#endif

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

	VPRINTK("ENTER\n");

	WARN_ON(ATA_MAX_QUEUE > AHCI_MAX_CMDS);

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

	/* The AHCI driver can only drive the SATA ports, the PATA driver
	   can drive them all so if both drivers are selected make sure
	   AHCI stays out of the way */
	if (pdev->vendor == PCI_VENDOR_ID_MARVELL && !marvell_enable)
		return -ENODEV;

	/* Promise's PDC42819 is a SAS/SATA controller that has an AHCI mode.
	 * At the moment, we can only use the AHCI mode. Let the users know
	 * that for SAS drives they're out of luck.
	 */
	if (pdev->vendor == PCI_VENDOR_ID_PROMISE)
		dev_printk(KERN_INFO, &pdev->dev, "PDC42819 "
			   "can only drive SATA devices with this driver\n");

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

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

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

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

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

	/* MCP65 revision A1 and A2 can't do MSI */
	if (board_id == board_ahci_mcp65 &&
	    (pdev->revision == 0xa1 || pdev->revision == 0xa2))
		hpriv->flags |= AHCI_HFLAG_NO_MSI;

	/* SB800 does NOT need the workaround to ignore SERR_INTERNAL */
	if (board_id == board_ahci_sb700 && pdev->revision >= 0x40)
		hpriv->flags &= ~AHCI_HFLAG_IGN_SERR_INTERNAL;

	/* only some SB600s can do 64bit DMA */
	if (ahci_sb600_enable_64bit(pdev))
		hpriv->flags &= ~AHCI_HFLAG_32BIT_ONLY;

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

	hpriv->mmio = pcim_iomap_table(pdev)[AHCI_PCI_BAR];

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

	/* prepare host */
	if (hpriv->cap & HOST_CAP_NCQ) {
		pi.flags |= ATA_FLAG_NCQ;
		/* Auto-activate optimization is supposed to be supported on
		   all AHCI controllers indicating NCQ support, but it seems
		   to be broken at least on some NVIDIA MCP79 chipsets.
		   Until we get info on which NVIDIA chipsets don't have this
		   issue, if any, disable AA on all NVIDIA AHCIs. */
		if (pdev->vendor != PCI_VENDOR_ID_NVIDIA)
			pi.flags |= ATA_FLAG_FPDMA_AA;
	}

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

	if (ahci_em_messages && (hpriv->cap & HOST_CAP_EMS)) {
		u8 messages;
		void __iomem *mmio = hpriv->mmio;
		u32 em_loc = readl(mmio + HOST_EM_LOC);
		u32 em_ctl = readl(mmio + HOST_EM_CTL);

		messages = (em_ctl & EM_CTRL_MSG_TYPE) >> 16;

		/* we only support LED message type right now */
		if ((messages & 0x01) && (ahci_em_messages == 1)) {
			/* store em_loc */
			hpriv->em_loc = ((em_loc >> 16) * 4);
			pi.flags |= ATA_FLAG_EM;
			if (!(em_ctl & EM_CTL_ALHD))
				pi.flags |= ATA_FLAG_SW_ACTIVITY;
		}
	}

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

	if (ahci_broken_suspend(pdev)) {
		hpriv->flags |= AHCI_HFLAG_NO_SUSPEND;
		dev_printk(KERN_WARNING, &pdev->dev,
			   "BIOS update required for suspend/resume\n");
	}

	if (ahci_broken_online(pdev)) {
		hpriv->flags |= AHCI_HFLAG_SRST_TOUT_IS_OFFLINE;
		dev_info(&pdev->dev,
			 "online status unreliable, applying workaround\n");
	}

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

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

	if (!(hpriv->cap & HOST_CAP_SSS) || ahci_ignore_sss)
		host->flags |= ATA_HOST_PARALLEL_SCAN;
	else
		printk(KERN_INFO "ahci: SSS flag set, parallel bus scan disabled\n");

	if (pi.flags & ATA_FLAG_EM)
		ahci_reset_em(host);

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

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

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

		/* set enclosure management message type */
		if (ap->flags & ATA_FLAG_EM)
			ap->em_message_type = ahci_em_messages;


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

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

	/* apply gtf filter quirk */
	ahci_gtf_filter_workaround(host);

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

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

	ahci_pci_init_controller(host);
	ahci_print_info(host);

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

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

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


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

module_init(ahci_init);
module_exit(ahci_exit);