Merge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev

* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev: (29 commits)
  libata: implement EH fast drain
  libata: schedule probing after SError access failure during autopsy
  libata: clear HOTPLUG flag after a reset
  libata: reorganize ata_ehi_hotplugged()
  libata: improve SCSI scan failure handling
  libata: quickly trigger SATA SPD down after debouncing failed
  libata: improve SATA PHY speed down logic
  The SATA controller device ID is different according to
  ahci: implement SCR_NOTIFICATION r/w
  ahci: make NO_NCQ handling more consistent
  libata: make ->scr_read/write callbacks return error code
  libata: implement AC_ERR_NCQ
  libata: improve EH report formatting
  sata_sil24: separate out sil24_do_softreset()
  sata_sil24: separate out sil24_exec_polled_cmd()
  sata_sil24: replace sil24_update_tf() with sil24_read_tf()
  ahci: separate out ahci_do_softreset()
  ahci: separate out ahci_exec_polled_cmd()
  ahci: separate out ahci_kick_engine()
  ahci: use deadline instead of fixed timeout for 1st FIS for SRST
  ...

21 files changed, 816 insertions, 416 deletions

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 11e4eb9f304..06f212ff2b4 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -99,6 +99,7 @@ enum {
 	HOST_CAP_SSC		= (1 << 14), /* Slumber capable */
 	HOST_CAP_CLO		= (1 << 24), /* Command List Override support */
 	HOST_CAP_SSS		= (1 << 27), /* Staggered Spin-up */
+	HOST_CAP_SNTF		= (1 << 29), /* SNotification register */
 	HOST_CAP_NCQ		= (1 << 30), /* Native Command Queueing */
 	HOST_CAP_64		= (1 << 31), /* PCI DAC (64-bit DMA) support */
 
@@ -113,11 +114,11 @@ enum {
 	PORT_TFDATA		= 0x20,	/* taskfile data */
 	PORT_SIG		= 0x24,	/* device TF signature */
 	PORT_CMD_ISSUE		= 0x38, /* command issue */
-	PORT_SCR		= 0x28, /* SATA phy register block */
 	PORT_SCR_STAT		= 0x28, /* SATA phy register: SStatus */
 	PORT_SCR_CTL		= 0x2c, /* SATA phy register: SControl */
 	PORT_SCR_ERR		= 0x30, /* SATA phy register: SError */
 	PORT_SCR_ACT		= 0x34, /* SATA phy register: SActive */
+	PORT_SCR_NTF		= 0x3c, /* SATA phy register: SNotification */
 
 	/* PORT_IRQ_{STAT,MASK} bits */
 	PORT_IRQ_COLD_PRES	= (1 << 31), /* cold presence detect */
@@ -216,8 +217,8 @@ struct ahci_port_priv {
 	unsigned int		ncq_saw_sdb:1;
 };
 
-static u32 ahci_scr_read (struct ata_port *ap, unsigned int sc_reg);
-static void ahci_scr_write (struct ata_port *ap, unsigned int sc_reg, u32 val);
+static int ahci_scr_read(struct ata_port *ap, unsigned int sc_reg, u32 *val);
+static int ahci_scr_write(struct ata_port *ap, unsigned int sc_reg, u32 val);
 static int ahci_init_one (struct pci_dev *pdev, const struct pci_device_id *ent);
 static unsigned int ahci_qc_issue(struct ata_queued_cmd *qc);
 static void ahci_irq_clear(struct ata_port *ap);
@@ -417,7 +418,10 @@ static const struct pci_device_id ahci_pci_tbl[] = {
 
 	/* ATI */
 	{ PCI_VDEVICE(ATI, 0x4380), board_ahci_sb600 }, /* ATI SB600 */
-	{ PCI_VDEVICE(ATI, 0x4390), board_ahci_sb600 }, /* ATI SB700 */
+	{ PCI_VDEVICE(ATI, 0x4390), board_ahci_sb600 }, /* ATI SB700 IDE */
+	{ PCI_VDEVICE(ATI, 0x4391), board_ahci_sb600 }, /* ATI SB700 AHCI */
+	{ PCI_VDEVICE(ATI, 0x4392), board_ahci_sb600 }, /* ATI SB700 nraid5 */
+	{ PCI_VDEVICE(ATI, 0x4393), board_ahci_sb600 }, /* ATI SB700 raid5 */
 
 	/* VIA */
 	{ PCI_VDEVICE(VIA, 0x3349), board_ahci_vt8251 }, /* VIA VT8251 */
@@ -545,13 +549,19 @@ static void ahci_save_initial_config(struct pci_dev *pdev,
 	hpriv->saved_cap = cap = readl(mmio + HOST_CAP);
 	hpriv->saved_port_map = port_map = readl(mmio + HOST_PORTS_IMPL);
 
-	/* some chips lie about 64bit support */
+	/* some chips have errata preventing 64bit use */
 	if ((cap & HOST_CAP_64) && (pi->flags & AHCI_FLAG_32BIT_ONLY)) {
 		dev_printk(KERN_INFO, &pdev->dev,
 			   "controller can't do 64bit DMA, forcing 32bit\n");
 		cap &= ~HOST_CAP_64;
 	}
 
+	if ((cap & HOST_CAP_NCQ) && (pi->flags & AHCI_FLAG_NO_NCQ)) {
+		dev_printk(KERN_INFO, &pdev->dev,
+			   "controller can't do NCQ, turning off CAP_NCQ\n");
+		cap &= ~HOST_CAP_NCQ;
+	}
+
 	/* fixup zero port_map */
 	if (!port_map) {
 		port_map = (1 << ahci_nr_ports(cap)) - 1;
@@ -625,38 +635,45 @@ static void ahci_restore_initial_config(struct ata_host *host)
 	(void) readl(mmio + HOST_PORTS_IMPL);	/* flush */
 }
 
-static u32 ahci_scr_read (struct ata_port *ap, unsigned int sc_reg_in)
+static unsigned ahci_scr_offset(struct ata_port *ap, unsigned int sc_reg)
 {
-	unsigned int sc_reg;
-
-	switch (sc_reg_in) {
-	case SCR_STATUS:	sc_reg = 0; break;
-	case SCR_CONTROL:	sc_reg = 1; break;
-	case SCR_ERROR:		sc_reg = 2; break;
-	case SCR_ACTIVE:	sc_reg = 3; break;
-	default:
-		return 0xffffffffU;
-	}
+	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;
 
-	return readl(ap->ioaddr.scr_addr + (sc_reg * 4));
+	if (sc_reg < ARRAY_SIZE(offset) &&
+	    (sc_reg != SCR_NOTIFICATION || (hpriv->cap & HOST_CAP_SNTF)))
+		return offset[sc_reg];
+	return 0;
 }
 
-
-static void ahci_scr_write (struct ata_port *ap, unsigned int sc_reg_in,
-			       u32 val)
+static int ahci_scr_read(struct ata_port *ap, unsigned int sc_reg, u32 *val)
 {
-	unsigned int sc_reg;
-
-	switch (sc_reg_in) {
-	case SCR_STATUS:	sc_reg = 0; break;
-	case SCR_CONTROL:	sc_reg = 1; break;
-	case SCR_ERROR:		sc_reg = 2; break;
-	case SCR_ACTIVE:	sc_reg = 3; break;
-	default:
-		return;
+	void __iomem *port_mmio = ahci_port_base(ap);
+	int offset = ahci_scr_offset(ap, sc_reg);
+
+	if (offset) {
+		*val = readl(port_mmio + offset);
+		return 0;
 	}
+	return -EINVAL;
+}
 
-	writel(val, ap->ioaddr.scr_addr + (sc_reg * 4));
+static int ahci_scr_write(struct ata_port *ap, unsigned int sc_reg, u32 val)
+{
+	void __iomem *port_mmio = ahci_port_base(ap);
+	int offset = ahci_scr_offset(ap, sc_reg);
+
+	if (offset) {
+		writel(val, port_mmio + offset);
+		return 0;
+	}
+	return -EINVAL;
 }
 
 static void ahci_start_engine(struct ata_port *ap)
@@ -948,37 +965,87 @@ static void ahci_fill_cmd_slot(struct ahci_port_priv *pp, unsigned int tag,
 	pp->cmd_slot[tag].tbl_addr_hi = cpu_to_le32((cmd_tbl_dma >> 16) >> 16);
 }
 
-static int ahci_clo(struct ata_port *ap)
+static int ahci_kick_engine(struct ata_port *ap, int force_restart)
 {
 	void __iomem *port_mmio = ap->ioaddr.cmd_addr;
 	struct ahci_host_priv *hpriv = ap->host->private_data;
 	u32 tmp;
+	int busy, rc;
+
+	/* do we need to kick the port? */
+	busy = ahci_check_status(ap) & (ATA_BUSY | ATA_DRQ);
+	if (!busy && !force_restart)
+		return 0;
+
+	/* stop engine */
+	rc = ahci_stop_engine(ap);
+	if (rc)
+		goto out_restart;
 
-	if (!(hpriv->cap & HOST_CAP_CLO))
-		return -EOPNOTSUPP;
+	/* need to do CLO? */
+	if (!busy) {
+		rc = 0;
+		goto out_restart;
+	}
 
+	if (!(hpriv->cap & HOST_CAP_CLO)) {
+		rc = -EOPNOTSUPP;
+		goto out_restart;
+	}
+
+	/* perform CLO */
 	tmp = readl(port_mmio + PORT_CMD);
 	tmp |= PORT_CMD_CLO;
 	writel(tmp, port_mmio + PORT_CMD);
 
+	rc = 0;
 	tmp = ata_wait_register(port_mmio + PORT_CMD,
 				PORT_CMD_CLO, PORT_CMD_CLO, 1, 500);
 	if (tmp & PORT_CMD_CLO)
-		return -EIO;
+		rc = -EIO;
 
-	return 0;
+	/* restart engine */
+ out_restart:
+	ahci_start_engine(ap);
+	return rc;
 }
 
-static int ahci_softreset(struct ata_port *ap, unsigned int *class,
-			  unsigned long deadline)
+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);
-	const u32 cmd_fis_len = 5; /* five dwords */
+	u8 *fis = pp->cmd_tbl;
+	u32 tmp;
+
+	/* prep the command */
+	ata_tf_to_fis(tf, pmp, is_cmd, fis);
+	ahci_fill_cmd_slot(pp, 0, cmd_fis_len | flags | (pmp << 12));
+
+	/* issue & wait */
+	writel(1, port_mmio + PORT_CMD_ISSUE);
+
+	if (timeout_msec) {
+		tmp = ata_wait_register(port_mmio + PORT_CMD_ISSUE, 0x1, 0x1,
+					1, timeout_msec);
+		if (tmp & 0x1) {
+			ahci_kick_engine(ap, 1);
+			return -EBUSY;
+		}
+	} else
+		readl(port_mmio + PORT_CMD_ISSUE);	/* flush */
+
+	return 0;
+}
+
+static int ahci_do_softreset(struct ata_port *ap, unsigned int *class,
+			     int pmp, unsigned long deadline)
+{
 	const char *reason = NULL;
+	unsigned long now, msecs;
 	struct ata_taskfile tf;
-	u32 tmp;
-	u8 *fis;
 	int rc;
 
 	DPRINTK("ENTER\n");
@@ -990,43 +1057,22 @@ static int ahci_softreset(struct ata_port *ap, unsigned int *class,
 	}
 
 	/* prepare for SRST (AHCI-1.1 10.4.1) */
-	rc = ahci_stop_engine(ap);
-	if (rc) {
-		reason = "failed to stop engine";
-		goto fail_restart;
-	}
-
-	/* check BUSY/DRQ, perform Command List Override if necessary */
-	if (ahci_check_status(ap) & (ATA_BUSY | ATA_DRQ)) {
-		rc = ahci_clo(ap);
-
-		if (rc == -EOPNOTSUPP) {
-			reason = "port busy but CLO unavailable";
-			goto fail_restart;
-		} else if (rc) {
-			reason = "port busy but CLO failed";
-			goto fail_restart;
-		}
-	}
-
-	/* restart engine */
-	ahci_start_engine(ap);
+	rc = ahci_kick_engine(ap, 1);
+	if (rc)
+		ata_port_printk(ap, KERN_WARNING,
+				"failed to reset engine (errno=%d)", rc);
 
 	ata_tf_init(ap->device, &tf);
-	fis = pp->cmd_tbl;
 
 	/* issue the first D2H Register FIS */
-	ahci_fill_cmd_slot(pp, 0,
-			   cmd_fis_len | AHCI_CMD_RESET | AHCI_CMD_CLR_BUSY);
+	msecs = 0;
+	now = jiffies;
+	if (time_after(now, deadline))
+		msecs = jiffies_to_msecs(deadline - now);
 
 	tf.ctl |= ATA_SRST;
-	ata_tf_to_fis(&tf, fis, 0);
-	fis[1] &= ~(1 << 7);	/* turn off Command FIS bit */
-
-	writel(1, port_mmio + PORT_CMD_ISSUE);
-
-	tmp = ata_wait_register(port_mmio + PORT_CMD_ISSUE, 0x1, 0x1, 1, 500);
-	if (tmp & 0x1) {
+	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;
@@ -1036,14 +1082,8 @@ static int ahci_softreset(struct ata_port *ap, unsigned int *class,
 	msleep(1);
 
 	/* issue the second D2H Register FIS */
-	ahci_fill_cmd_slot(pp, 0, cmd_fis_len);
-
 	tf.ctl &= ~ATA_SRST;
-	ata_tf_to_fis(&tf, fis, 0);
-	fis[1] &= ~(1 << 7);	/* turn off Command FIS bit */
-
-	writel(1, port_mmio + PORT_CMD_ISSUE);
-	readl(port_mmio + PORT_CMD_ISSUE);	/* flush */
+	ahci_exec_polled_cmd(ap, pmp, &tf, 0, 0, 0);
 
 	/* spec mandates ">= 2ms" before checking status.
 	 * We wait 150ms, because that was the magic delay used for
@@ -1066,13 +1106,17 @@ static int ahci_softreset(struct ata_port *ap, unsigned int *class,
 	DPRINTK("EXIT, class=%u\n", *class);
 	return 0;
 
- fail_restart:
-	ahci_start_engine(ap);
  fail:
 	ata_port_printk(ap, KERN_ERR, "softreset failed (%s)\n", reason);
 	return rc;
 }
 
+static int ahci_softreset(struct ata_port *ap, unsigned int *class,
+			  unsigned long deadline)
+{
+	return ahci_do_softreset(ap, class, 0, deadline);
+}
+
 static int ahci_hardreset(struct ata_port *ap, unsigned int *class,
 			  unsigned long deadline)
 {
@@ -1088,7 +1132,7 @@ static int ahci_hardreset(struct ata_port *ap, unsigned int *class,
 	/* clear D2H reception area to properly wait for D2H FIS */
 	ata_tf_init(ap->device, &tf);
 	tf.command = 0x80;
-	ata_tf_to_fis(&tf, d2h_fis, 0);
+	ata_tf_to_fis(&tf, 0, 0, d2h_fis);
 
 	rc = sata_std_hardreset(ap, class, deadline);
 
@@ -1106,6 +1150,7 @@ static int ahci_hardreset(struct ata_port *ap, unsigned int *class,
 static int ahci_vt8251_hardreset(struct ata_port *ap, unsigned int *class,
 				 unsigned long deadline)
 {
+	u32 serror;
 	int rc;
 
 	DPRINTK("ENTER\n");
@@ -1116,7 +1161,8 @@ static int ahci_vt8251_hardreset(struct ata_port *ap, unsigned int *class,
 				 deadline);
 
 	/* vt8251 needs SError cleared for the port to operate */
-	ahci_scr_write(ap, SCR_ERROR, ahci_scr_read(ap, SCR_ERROR));
+	ahci_scr_read(ap, SCR_ERROR, &serror);
+	ahci_scr_write(ap, SCR_ERROR, serror);
 
 	ahci_start_engine(ap);
 
@@ -1205,7 +1251,7 @@ static void ahci_qc_prep(struct ata_queued_cmd *qc)
 	 */
 	cmd_tbl = pp->cmd_tbl + qc->tag * AHCI_CMD_TBL_SZ;
 
-	ata_tf_to_fis(&qc->tf, cmd_tbl, 0);
+	ata_tf_to_fis(&qc->tf, 0, 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);
@@ -1238,7 +1284,7 @@ static void ahci_error_intr(struct ata_port *ap, u32 irq_stat)
 	ata_ehi_clear_desc(ehi);
 
 	/* AHCI needs SError cleared; otherwise, it might lock up */
-	serror = ahci_scr_read(ap, SCR_ERROR);
+	ahci_scr_read(ap, SCR_ERROR, &serror);
 	ahci_scr_write(ap, SCR_ERROR, serror);
 
 	/* analyze @irq_stat */
@@ -1262,12 +1308,12 @@ static void ahci_error_intr(struct ata_port *ap, u32 irq_stat)
 	if (irq_stat & PORT_IRQ_IF_ERR) {
 		err_mask |= AC_ERR_ATA_BUS;
 		action |= ATA_EH_SOFTRESET;
-		ata_ehi_push_desc(ehi, ", interface fatal error");
+		ata_ehi_push_desc(ehi, "interface fatal error");
 	}
 
 	if (irq_stat & (PORT_IRQ_CONNECT | PORT_IRQ_PHYRDY)) {
 		ata_ehi_hotplugged(ehi);
-		ata_ehi_push_desc(ehi, ", %s", irq_stat & PORT_IRQ_CONNECT ?
+		ata_ehi_push_desc(ehi, "%s", irq_stat & PORT_IRQ_CONNECT ?
 			"connection status changed" : "PHY RDY changed");
 	}
 
@@ -1276,7 +1322,7 @@ static void ahci_error_intr(struct ata_port *ap, u32 irq_stat)
 
 		err_mask |= AC_ERR_HSM;
 		action |= ATA_EH_SOFTRESET;
-		ata_ehi_push_desc(ehi, ", unknown FIS %08x %08x %08x %08x",
+		ata_ehi_push_desc(ehi, "unknown FIS %08x %08x %08x %08x",
 				  unk[0], unk[1], unk[2], unk[3]);
 	}
 
@@ -1512,11 +1558,17 @@ static void ahci_post_internal_cmd(struct ata_queued_cmd *qc)
 {
 	struct ata_port *ap = qc->ap;
 
-	if (qc->flags & ATA_QCFLAG_FAILED) {
-		/* make DMA engine forget about the failed command */
-		ahci_stop_engine(ap);
-		ahci_start_engine(ap);
-	}
+	/* make DMA engine forget about the failed command */
+	if (qc->flags & ATA_QCFLAG_FAILED)
+		ahci_kick_engine(ap, 1);
+}
+
+static int ahci_port_resume(struct ata_port *ap)
+{
+	ahci_power_up(ap);
+	ahci_start_port(ap);
+
+	return 0;
 }
 
 #ifdef CONFIG_PM
@@ -1536,14 +1588,6 @@ static int ahci_port_suspend(struct ata_port *ap, pm_message_t mesg)
 	return rc;
 }
 
-static int ahci_port_resume(struct ata_port *ap)
-{
-	ahci_power_up(ap);
-	ahci_start_port(ap);
-
-	return 0;
-}
-
 static int ahci_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg)
 {
 	struct ata_host *host = dev_get_drvdata(&pdev->dev);
@@ -1734,12 +1778,13 @@ static void ahci_print_info(struct ata_host *host)
 
 	dev_printk(KERN_INFO, &pdev->dev,
 		"flags: "
-	       	"%s%s%s%s%s%s"
-	       	"%s%s%s%s%s%s%s\n"
+		"%s%s%s%s%s%s%s"
+		"%s%s%s%s%s%s%s\n"
 	       	,
 
 		cap & (1 << 31) ? "64bit " : "",
 		cap & (1 << 30) ? "ncq " : "",
+		cap & (1 << 29) ? "sntf " : "",
 		cap & (1 << 28) ? "ilck " : "",
 		cap & (1 << 27) ? "stag " : "",
 		cap & (1 << 26) ? "pm " : "",
@@ -1794,7 +1839,7 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	ahci_save_initial_config(pdev, &pi, hpriv);
 
 	/* prepare host */
-	if (!(pi.flags & AHCI_FLAG_NO_NCQ) && (hpriv->cap & HOST_CAP_NCQ))
+	if (hpriv->cap & HOST_CAP_NCQ)
 		pi.flags |= ATA_FLAG_NCQ;
 
 	host = ata_host_alloc_pinfo(&pdev->dev, ppi, fls(hpriv->port_map));
@@ -1808,10 +1853,8 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		void __iomem *port_mmio = ahci_port_base(ap);
 
 		/* standard SATA port setup */
-		if (hpriv->port_map & (1 << i)) {
+		if (hpriv->port_map & (1 << i))
 			ap->ioaddr.cmd_addr = port_mmio;
-			ap->ioaddr.scr_addr = port_mmio + PORT_SCR;
-		}
 
 		/* disabled/not-implemented port */
 		else
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 88e2dd0983b..6001aae0b88 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -111,8 +111,9 @@ MODULE_VERSION(DRV_VERSION);
 /**
  *	ata_tf_to_fis - Convert ATA taskfile to SATA FIS structure
  *	@tf: Taskfile to convert
- *	@fis: Buffer into which data will output
  *	@pmp: Port multiplier port
+ *	@is_cmd: This FIS is for command
+ *	@fis: Buffer into which data will output
  *
  *	Converts a standard ATA taskfile to a Serial ATA
  *	FIS structure (Register - Host to Device).
@@ -120,12 +121,13 @@ MODULE_VERSION(DRV_VERSION);
  *	LOCKING:
  *	Inherited from caller.
  */
-
-void ata_tf_to_fis(const struct ata_taskfile *tf, u8 *fis, u8 pmp)
+void ata_tf_to_fis(const struct ata_taskfile *tf, u8 pmp, int is_cmd, u8 *fis)
 {
-	fis[0] = 0x27;	/* Register - Host to Device FIS */
-	fis[1] = (pmp & 0xf) | (1 << 7); /* Port multiplier number,
-					    bit 7 indicates Command FIS */
+	fis[0] = 0x27;			/* Register - Host to Device FIS */
+	fis[1] = pmp & 0xf;		/* Port multiplier number*/
+	if (is_cmd)
+		fis[1] |= (1 << 7);	/* bit 7 indicates Command FIS */
+
 	fis[2] = tf->command;
 	fis[3] = tf->feature;
 
@@ -2387,21 +2389,35 @@ int sata_down_spd_limit(struct ata_port *ap)
 	u32 sstatus, spd, mask;
 	int rc, highbit;
 
+	if (!sata_scr_valid(ap))
+		return -EOPNOTSUPP;
+
+	/* If SCR can be read, use it to determine the current SPD.
+	 * If not, use cached value in ap->sata_spd.
+	 */
 	rc = sata_scr_read(ap, SCR_STATUS, &sstatus);
-	if (rc)
-		return rc;
+	if (rc == 0)
+		spd = (sstatus >> 4) & 0xf;
+	else
+		spd = ap->sata_spd;
 
 	mask = ap->sata_spd_limit;
 	if (mask <= 1)
 		return -EINVAL;
+
+	/* unconditionally mask off the highest bit */
 	highbit = fls(mask) - 1;
 	mask &= ~(1 << highbit);
 
-	spd = (sstatus >> 4) & 0xf;
-	if (spd <= 1)
-		return -EINVAL;
-	spd--;
-	mask &= (1 << spd) - 1;
+	/* Mask off all speeds higher than or equal to the current
+	 * one.  Force 1.5Gbps if current SPD is not available.
+	 */
+	if (spd > 1)
+		mask &= (1 << (spd - 1)) - 1;
+	else
+		mask &= 1;
+
+	/* were we already at the bottom? */
 	if (!mask)
 		return -EINVAL;
 
@@ -3251,9 +3267,11 @@ int sata_phy_debounce(struct ata_port *ap, const unsigned long *params,
 		last = cur;
 		last_jiffies = jiffies;
 
-		/* check deadline */
+		/* Check deadline.  If debouncing failed, return
+		 * -EPIPE to tell upper layer to lower link speed.
+		 */
 		if (time_after(jiffies, deadline))
-			return -EBUSY;
+			return -EPIPE;
 	}
 }
 
@@ -3769,6 +3787,7 @@ static const struct ata_blacklist_entry ata_device_blacklist [] = {
 	{ "Hitachi HTS541616J9SA00", "SB4OC70P", ATA_HORKAGE_NONCQ, },
 	{ "WDC WD740ADFD-00NLR1", NULL,		ATA_HORKAGE_NONCQ, },
 	{ "FUJITSU MHV2080BH",	"00840028",	ATA_HORKAGE_NONCQ, },
+	{ "ST9160821AS",	"3.CLF",	ATA_HORKAGE_NONCQ, },
 
 	/* Devices with NCQ limits */
 
@@ -5729,10 +5748,8 @@ int sata_scr_valid(struct ata_port *ap)
  */
 int sata_scr_read(struct ata_port *ap, int reg, u32 *val)
 {
-	if (sata_scr_valid(ap)) {
-		*val = ap->ops->scr_read(ap, reg);
-		return 0;
-	}
+	if (sata_scr_valid(ap))
+		return ap->ops->scr_read(ap, reg, val);
 	return -EOPNOTSUPP;
 }
 
@@ -5754,10 +5771,8 @@ int sata_scr_read(struct ata_port *ap, int reg, u32 *val)
  */
 int sata_scr_write(struct ata_port *ap, int reg, u32 val)
 {
-	if (sata_scr_valid(ap)) {
-		ap->ops->scr_write(ap, reg, val);
-		return 0;
-	}
+	if (sata_scr_valid(ap))
+		return ap->ops->scr_write(ap, reg, val);
 	return -EOPNOTSUPP;
 }
 
@@ -5778,10 +5793,13 @@ int sata_scr_write(struct ata_port *ap, int reg, u32 val)
  */
 int sata_scr_write_flush(struct ata_port *ap, int reg, u32 val)
 {
+	int rc;
+
 	if (sata_scr_valid(ap)) {
-		ap->ops->scr_write(ap, reg, val);
-		ap->ops->scr_read(ap, reg);
-		return 0;
+		rc = ap->ops->scr_write(ap, reg, val);
+		if (rc == 0)
+			rc = ap->ops->scr_read(ap, reg, &val);
+		return rc;
 	}
 	return -EOPNOTSUPP;
 }
@@ -5993,6 +6011,7 @@ void ata_dev_init(struct ata_device *dev)
 
 	/* SATA spd limit is bound to the first device */
 	ap->sata_spd_limit = ap->hw_sata_spd_limit;
+	ap->sata_spd = 0;
 
 	/* High bits of dev->flags are used to record warm plug
 	 * requests which occur asynchronously.  Synchronize using
@@ -6058,6 +6077,9 @@ struct ata_port *ata_port_alloc(struct ata_host *host)
 	INIT_WORK(&ap->scsi_rescan_task, ata_scsi_dev_rescan);
 	INIT_LIST_HEAD(&ap->eh_done_q);
 	init_waitqueue_head(&ap->eh_wait_q);
+	init_timer_deferrable(&ap->fastdrain_timer);
+	ap->fastdrain_timer.function = ata_eh_fastdrain_timerfn;
+	ap->fastdrain_timer.data = (unsigned long)ap;
 
 	ap->cbl = ATA_CBL_NONE;
 
@@ -6434,7 +6456,7 @@ int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)
 	for (i = 0; i < host->n_ports; i++) {
 		struct ata_port *ap = host->ports[i];
 
-		ata_scsi_scan_host(ap);
+		ata_scsi_scan_host(ap, 1);
 	}
 
 	return 0;
@@ -6942,6 +6964,9 @@ EXPORT_SYMBOL_GPL(ata_pci_default_filter);
 EXPORT_SYMBOL_GPL(ata_pci_clear_simplex);
 #endif /* CONFIG_PCI */
 
+EXPORT_SYMBOL_GPL(__ata_ehi_push_desc);
+EXPORT_SYMBOL_GPL(ata_ehi_push_desc);
+EXPORT_SYMBOL_GPL(ata_ehi_clear_desc);
 EXPORT_SYMBOL_GPL(ata_eng_timeout);
 EXPORT_SYMBOL_GPL(ata_port_schedule_eh);
 EXPORT_SYMBOL_GPL(ata_port_abort);
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 9aa62a0754f..ac6ceed4bb6 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -56,6 +56,7 @@ enum {
  */
 enum {
 	ATA_EH_PRERESET_TIMEOUT		= 10 * HZ,
+	ATA_EH_FASTDRAIN_INTERVAL	= 3 * HZ,
 };
 
 /* The following table determines how we sequence resets.  Each entry
@@ -85,6 +86,71 @@ static void ata_eh_handle_port_resume(struct ata_port *ap)
 { }
 #endif /* CONFIG_PM */
 
+static void __ata_ehi_pushv_desc(struct ata_eh_info *ehi, const char *fmt,
+				 va_list args)
+{
+	ehi->desc_len += vscnprintf(ehi->desc + ehi->desc_len,
+				     ATA_EH_DESC_LEN - ehi->desc_len,
+				     fmt, args);
+}
+
+/**
+ *	__ata_ehi_push_desc - push error description without adding separator
+ *	@ehi: target EHI
+ *	@fmt: printf format string
+ *
+ *	Format string according to @fmt and append it to @ehi->desc.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host lock)
+ */
+void __ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
+{
+	va_list args;
+
+	va_start(args, fmt);
+	__ata_ehi_pushv_desc(ehi, fmt, args);
+	va_end(args);
+}
+
+/**
+ *	ata_ehi_push_desc - push error description with separator
+ *	@ehi: target EHI
+ *	@fmt: printf format string
+ *
+ *	Format string according to @fmt and append it to @ehi->desc.
+ *	If @ehi->desc is not empty, ", " is added in-between.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host lock)
+ */
+void ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
+{
+	va_list args;
+
+	if (ehi->desc_len)
+		__ata_ehi_push_desc(ehi, ", ");
+
+	va_start(args, fmt);
+	__ata_ehi_pushv_desc(ehi, fmt, args);
+	va_end(args);
+}
+
+/**
+ *	ata_ehi_clear_desc - clean error description
+ *	@ehi: target EHI
+ *
+ *	Clear @ehi->desc.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host lock)
+ */
+void ata_ehi_clear_desc(struct ata_eh_info *ehi)
+{
+	ehi->desc[0] = '\0';
+	ehi->desc_len = 0;
+}
+
 static void ata_ering_record(struct ata_ering *ering, int is_io,
 			     unsigned int err_mask)
 {
@@ -296,6 +362,9 @@ void ata_scsi_error(struct Scsi_Host *host)
  repeat:
 	/* invoke error handler */
 	if (ap->ops->error_handler) {
+		/* kill fast drain timer */
+		del_timer_sync(&ap->fastdrain_timer);
+
 		/* process port resume request */
 		ata_eh_handle_port_resume(ap);
 
@@ -511,6 +580,94 @@ void ata_eng_timeout(struct ata_port *ap)
 	DPRINTK("EXIT\n");
 }
 
+static int ata_eh_nr_in_flight(struct ata_port *ap)
+{
+	unsigned int tag;
+	int nr = 0;
+
+	/* count only non-internal commands */
+	for (tag = 0; tag < ATA_MAX_QUEUE - 1; tag++)
+		if (ata_qc_from_tag(ap, tag))
+			nr++;
+
+	return nr;
+}
+
+void ata_eh_fastdrain_timerfn(unsigned long arg)
+{
+	struct ata_port *ap = (void *)arg;
+	unsigned long flags;
+	int cnt;
+
+	spin_lock_irqsave(ap->lock, flags);
+
+	cnt = ata_eh_nr_in_flight(ap);
+
+	/* are we done? */
+	if (!cnt)
+		goto out_unlock;
+
+	if (cnt == ap->fastdrain_cnt) {
+		unsigned int tag;
+
+		/* No progress during the last interval, tag all
+		 * in-flight qcs as timed out and freeze the port.
+		 */
+		for (tag = 0; tag < ATA_MAX_QUEUE - 1; tag++) {
+			struct ata_queued_cmd *qc = ata_qc_from_tag(ap, tag);
+			if (qc)
+				qc->err_mask |= AC_ERR_TIMEOUT;
+		}
+
+		ata_port_freeze(ap);
+	} else {
+		/* some qcs have finished, give it another chance */
+		ap->fastdrain_cnt = cnt;
+		ap->fastdrain_timer.expires =
+			jiffies + ATA_EH_FASTDRAIN_INTERVAL;
+		add_timer(&ap->fastdrain_timer);
+	}
+
+ out_unlock:
+	spin_unlock_irqrestore(ap->lock, flags);
+}
+
+/**
+ *	ata_eh_set_pending - set ATA_PFLAG_EH_PENDING and activate fast drain
+ *	@ap: target ATA port
+ *	@fastdrain: activate fast drain
+ *
+ *	Set ATA_PFLAG_EH_PENDING and activate fast drain if @fastdrain
+ *	is non-zero and EH wasn't pending before.  Fast drain ensures
+ *	that EH kicks in in timely manner.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host lock)
+ */
+static void ata_eh_set_pending(struct ata_port *ap, int fastdrain)
+{
+	int cnt;
+
+	/* already scheduled? */
+	if (ap->pflags & ATA_PFLAG_EH_PENDING)
+		return;
+
+	ap->pflags |= ATA_PFLAG_EH_PENDING;
+
+	if (!fastdrain)
+		return;
+
+	/* do we have in-flight qcs? */
+	cnt = ata_eh_nr_in_flight(ap);
+	if (!cnt)
+		return;
+
+	/* activate fast drain */
+	ap->fastdrain_cnt = cnt;
+	ap->fastdrain_timer.expires = jiffies + ATA_EH_FASTDRAIN_INTERVAL;
+	add_timer(&ap->fastdrain_timer);
+}
+
 /**
  *	ata_qc_schedule_eh - schedule qc for error handling
  *	@qc: command to schedule error handling for
@@ -528,7 +685,7 @@ void ata_qc_schedule_eh(struct ata_queued_cmd *qc)
 	WARN_ON(!ap->ops->error_handler);
 
 	qc->flags |= ATA_QCFLAG_FAILED;
-	qc->ap->pflags |= ATA_PFLAG_EH_PENDING;
+	ata_eh_set_pending(ap, 1);
 
 	/* The following will fail if timeout has already expired.
 	 * ata_scsi_error() takes care of such scmds on EH entry.
@@ -555,7 +712,7 @@ void ata_port_schedule_eh(struct ata_port *ap)
 	if (ap->pflags & ATA_PFLAG_INITIALIZING)
 		return;
 
-	ap->pflags |= ATA_PFLAG_EH_PENDING;
+	ata_eh_set_pending(ap, 1);
 	scsi_schedule_eh(ap->scsi_host);
 
 	DPRINTK("port EH scheduled\n");
@@ -579,6 +736,9 @@ int ata_port_abort(struct ata_port *ap)
 
 	WARN_ON(!ap->ops->error_handler);
 
+	/* we're gonna abort all commands, no need for fast drain */
+	ata_eh_set_pending(ap, 0);
+
 	for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
 		struct ata_queued_cmd *qc = ata_qc_from_tag(ap, tag);
 
@@ -1130,7 +1290,7 @@ static void ata_eh_analyze_ncq_error(struct ata_port *ap)
 	/* we've got the perpetrator, condemn it */
 	qc = __ata_qc_from_tag(ap, tag);
 	memcpy(&qc->result_tf, &tf, sizeof(tf));
-	qc->err_mask |= AC_ERR_DEV;
+	qc->err_mask |= AC_ERR_DEV | AC_ERR_NCQ;
 	ehc->i.err_mask &= ~AC_ERR_DEV;
 }
 
@@ -1413,8 +1573,12 @@ static void ata_eh_autopsy(struct ata_port *ap)
 	if (rc == 0) {
 		ehc->i.serror |= serror;
 		ata_eh_analyze_serror(ap);
-	} else if (rc != -EOPNOTSUPP)
+	} else if (rc != -EOPNOTSUPP) {
+		/* SError read failed, force hardreset and probing */
+		ata_ehi_schedule_probe(&ehc->i);
 		ehc->i.action |= ATA_EH_HARDRESET;
+		ehc->i.err_mask |= AC_ERR_OTHER;
+	}
 
 	/* analyze NCQ failure */
 	ata_eh_analyze_ncq_error(ap);
@@ -1524,14 +1688,14 @@ static void ata_eh_report(struct ata_port *ap)
 			       ehc->i.err_mask, ap->sactive, ehc->i.serror,
 			       ehc->i.action, frozen);
 		if (desc)
-			ata_dev_printk(ehc->i.dev, KERN_ERR, "(%s)\n", desc);
+			ata_dev_printk(ehc->i.dev, KERN_ERR, "%s\n", desc);
 	} else {
 		ata_port_printk(ap, KERN_ERR, "exception Emask 0x%x "
 				"SAct 0x%x SErr 0x%x action 0x%x%s\n",
 				ehc->i.err_mask, ap->sactive, ehc->i.serror,
 				ehc->i.action, frozen);
 		if (desc)
-			ata_port_printk(ap, KERN_ERR, "(%s)\n", desc);
+			ata_port_printk(ap, KERN_ERR, "%s\n", desc);
 	}
 
 	for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
@@ -1551,7 +1715,7 @@ static void ata_eh_report(struct ata_port *ap)
 			"cmd %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
 			"tag %d cdb 0x%x data %u %s\n         "
 			"res %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
-			"Emask 0x%x (%s)\n",
+			"Emask 0x%x (%s)%s\n",
 			cmd->command, cmd->feature, cmd->nsect,
 			cmd->lbal, cmd->lbam, cmd->lbah,
 			cmd->hob_feature, cmd->hob_nsect,
@@ -1562,7 +1726,8 @@ static void ata_eh_report(struct ata_port *ap)
 			res->lbal, res->lbam, res->lbah,
 			res->hob_feature, res->hob_nsect,
 			res->hob_lbal, res->hob_lbam, res->hob_lbah,
-			res->device, qc->err_mask, ata_err_string(qc->err_mask));
+			res->device, qc->err_mask, ata_err_string(qc->err_mask),
+			qc->err_mask & AC_ERR_NCQ ? " <F>" : "");
 	}
 }
 
@@ -1648,7 +1813,7 @@ static int ata_eh_reset(struct ata_port *ap, int classify,
 			} else
 				ata_port_printk(ap, KERN_ERR,
 					"prereset failed (errno=%d)\n", rc);
-			return rc;
+			goto out;
 		}
 	}
 
@@ -1661,7 +1826,8 @@ static int ata_eh_reset(struct ata_port *ap, int classify,
 		/* prereset