Commit 3529a233 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

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

* 'alpm' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev:
  [libata] AHCI: add hw link power management support
  [libata] Link power management infrastructure
parents 00cda56d 31556594

Documentation/scsi/link_power_management_policy.txt

0 → 100644
+19 −0
Original line number Diff line number Diff line 
This parameter allows the user to set the link (interface) power management.

There are 3 possible options:



Value			Effect

----------------------------------------------------------------------------

min_power		Tell the controller to try to make the link use the

			least possible power when possible.  This may

			sacrifice some performance due to increased latency

			when coming out of lower power states.



max_performance		Generally, this means no power management.  Tell

			the controller to have performance be a priority

			over power management.



medium_power		Tell the controller to enter a lower power state

			when possible, but do not enter the lowest power

			state, thus improving latency over min_power setting.

drivers/ata/ahci.c

+155 −2
Original line number Diff line number Diff line
@@ -49,6 +49,9 @@ 
#define DRV_NAME	"ahci"

#define DRV_VERSION	"3.0"



static int ahci_enable_alpm(struct ata_port *ap,

		enum link_pm policy);

static void ahci_disable_alpm(struct ata_port *ap);



enum {

	AHCI_PCI_BAR		= 5,
@@ -99,6 +102,7 @@ enum { 
	HOST_CAP_SSC		= (1 << 14), /* Slumber capable */

	HOST_CAP_PMP		= (1 << 17), /* Port Multiplier support */

	HOST_CAP_CLO		= (1 << 24), /* Command List Override support */

	HOST_CAP_ALPM		= (1 << 26), /* Aggressive Link PM support */

	HOST_CAP_SSS		= (1 << 27), /* Staggered Spin-up */

	HOST_CAP_SNTF		= (1 << 29), /* SNotification register */

	HOST_CAP_NCQ		= (1 << 30), /* Native Command Queueing */
@@ -155,6 +159,8 @@ enum { 
				  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_PMP		= (1 << 17), /* PMP attached */

	PORT_CMD_LIST_ON	= (1 << 15), /* cmd list DMA engine running */
@@ -178,13 +184,14 @@ enum { 
	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 */



	/* ap->flags bits */

	AHCI_FLAG_NO_HOTPLUG		= (1 << 24), /* ignore PxSERR.DIAG.N */



	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_ACPI_SATA | ATA_FLAG_AN |

					  ATA_FLAG_IPM,

	AHCI_LFLAG_COMMON		= ATA_LFLAG_SKIP_D2H_BSY,

};
@@ -254,6 +261,11 @@ 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 struct class_device_attribute *ahci_shost_attrs[] = {

	&class_device_attr_link_power_management_policy,

	NULL

};



static struct scsi_host_template ahci_sht = {

	.module			= THIS_MODULE,

	.name			= DRV_NAME,
@@ -271,6 +283,7 @@ static struct scsi_host_template ahci_sht = { 
	.slave_configure	= ata_scsi_slave_config,

	.slave_destroy		= ata_scsi_slave_destroy,

	.bios_param		= ata_std_bios_param,

	.shost_attrs		= ahci_shost_attrs,

};



static const struct ata_port_operations ahci_ops = {
@@ -302,6 +315,8 @@ static const struct ata_port_operations ahci_ops = { 
	.port_suspend		= ahci_port_suspend,

	.port_resume		= ahci_port_resume,

#endif

	.enable_pm		= ahci_enable_alpm,

	.disable_pm		= ahci_disable_alpm,



	.port_start		= ahci_port_start,

	.port_stop		= ahci_port_stop,
@@ -836,6 +851,130 @@ static void ahci_power_up(struct ata_port *ap) 
	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, 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)

{
@@ -1504,6 +1643,17 @@ static void ahci_port_intr(struct ata_port *ap) 
	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, SCR_ERROR, ((1 << 16) | (1 << 18)));

	}



	if (unlikely(status & PORT_IRQ_ERROR)) {

		ahci_error_intr(ap, status);

		return;
@@ -2151,6 +2301,9 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) 
		ata_port_pbar_desc(ap, AHCI_PCI_BAR,

				   0x100 + ap->port_no * 0x80, "port");



		/* set initial link pm policy */

		ap->pm_policy = NOT_AVAILABLE;



		/* standard SATA port setup */

		if (hpriv->port_map & (1 << i))

			ap->ioaddr.cmd_addr = port_mmio;

drivers/ata/libata-core.c

+195 −1
Original line number Diff line number Diff line
@@ -620,6 +620,177 @@ void ata_dev_disable(struct ata_device *dev) 
	}

}



static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)

{

	struct ata_link *link = dev->link;

	struct ata_port *ap = link->ap;

	u32 scontrol;

	unsigned int err_mask;

	int rc;



	/*

	 * disallow DIPM for drivers which haven't set

	 * ATA_FLAG_IPM.  This is because when DIPM is enabled,

	 * phy ready will be set in the interrupt status on

	 * state changes, which will cause some drivers to

	 * think there are errors - additionally drivers will

	 * need to disable hot plug.

	 */

	if (!(ap->flags & ATA_FLAG_IPM) || !ata_dev_enabled(dev)) {

		ap->pm_policy = NOT_AVAILABLE;

		return -EINVAL;

	}



	/*

	 * For DIPM, we will only enable it for the

	 * min_power setting.

	 *

	 * Why?  Because Disks are too stupid to know that

	 * If the host rejects a request to go to SLUMBER

	 * they should retry at PARTIAL, and instead it

	 * just would give up.  So, for medium_power to

	 * work at all, we need to only allow HIPM.

	 */

	rc = sata_scr_read(link, SCR_CONTROL, &scontrol);

	if (rc)

		return rc;



	switch (policy) {

	case MIN_POWER:

		/* no restrictions on IPM transitions */

		scontrol &= ~(0x3 << 8);

		rc = sata_scr_write(link, SCR_CONTROL, scontrol);

		if (rc)

			return rc;



		/* enable DIPM */

		if (dev->flags & ATA_DFLAG_DIPM)

			err_mask = ata_dev_set_feature(dev,

					SETFEATURES_SATA_ENABLE, SATA_DIPM);

		break;

	case MEDIUM_POWER:

		/* allow IPM to PARTIAL */

		scontrol &= ~(0x1 << 8);

		scontrol |= (0x2 << 8);

		rc = sata_scr_write(link, SCR_CONTROL, scontrol);

		if (rc)

			return rc;



		/* disable DIPM */

		if (ata_dev_enabled(dev) && (dev->flags & ATA_DFLAG_DIPM))

			err_mask = ata_dev_set_feature(dev,

					SETFEATURES_SATA_DISABLE, SATA_DIPM);

		break;

	case NOT_AVAILABLE:

	case MAX_PERFORMANCE:

		/* disable all IPM transitions */

		scontrol |= (0x3 << 8);

		rc = sata_scr_write(link, SCR_CONTROL, scontrol);

		if (rc)

			return rc;



		/* disable DIPM */

		if (ata_dev_enabled(dev) && (dev->flags & ATA_DFLAG_DIPM))

			err_mask = ata_dev_set_feature(dev,

					SETFEATURES_SATA_DISABLE, SATA_DIPM);

		break;

	}



	/* FIXME: handle SET FEATURES failure */

	(void) err_mask;



	return 0;

}



/**

 *	ata_dev_enable_pm - enable SATA interface power management

 *	@device - device to enable ipm for

 *	@policy - the link power management policy

 *

 *	Enable SATA Interface power management.  This will enable

 *	Device Interface Power Management (DIPM) for min_power

 * 	policy, and then call driver specific callbacks for

 *	enabling Host Initiated Power management.

 *

 *	Locking: Caller.

 *	Returns: -EINVAL if IPM is not supported, 0 otherwise.

 */

void ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy)

{

	int rc = 0;

	struct ata_port *ap = dev->link->ap;



	/* set HIPM first, then DIPM */

	if (ap->ops->enable_pm)

		rc = ap->ops->enable_pm(ap, policy);

	if (rc)

		goto enable_pm_out;

	rc = ata_dev_set_dipm(dev, policy);



enable_pm_out:

	if (rc)

		ap->pm_policy = MAX_PERFORMANCE;

	else

		ap->pm_policy = policy;

	return /* rc */;	/* hopefully we can use 'rc' eventually */

}



/**

 *	ata_dev_disable_pm - disable SATA interface power management

 *	@device - device to enable ipm for

 *

 *	Disable SATA Interface power management.  This will disable

 *	Device Interface Power Management (DIPM) without changing

 * 	policy,  call driver specific callbacks for disabling Host

 * 	Initiated Power management.

 *

 *	Locking: Caller.

 *	Returns: void

 */

static void ata_dev_disable_pm(struct ata_device *dev)

{

	struct ata_port *ap = dev->link->ap;



	ata_dev_set_dipm(dev, MAX_PERFORMANCE);

	if (ap->ops->disable_pm)

		ap->ops->disable_pm(ap);

}



void ata_lpm_schedule(struct ata_port *ap, enum link_pm policy)

{

	ap->pm_policy = policy;

	ap->link.eh_info.action |= ATA_EHI_LPM;

	ap->link.eh_info.flags |= ATA_EHI_NO_AUTOPSY;

	ata_port_schedule_eh(ap);

}



static void ata_lpm_enable(struct ata_host *host)

{

	struct ata_link *link;

	struct ata_port *ap;

	struct ata_device *dev;

	int i;



	for (i = 0; i < host->n_ports; i++) {

		ap = host->ports[i];

		ata_port_for_each_link(link, ap) {

			ata_link_for_each_dev(dev, link)

				ata_dev_disable_pm(dev);

		}

	}

}



static void ata_lpm_disable(struct ata_host *host)

{

	int i;



	for (i = 0; i < host->n_ports; i++) {

		struct ata_port *ap = host->ports[i];

		ata_lpm_schedule(ap, ap->pm_policy);

	}

}





/**

 *	ata_devchk - PATA device presence detection

 *	@ap: ATA channel to examine
@@ -2101,6 +2272,13 @@ int ata_dev_configure(struct ata_device *dev) 
	if (dev->flags & ATA_DFLAG_LBA48)

		dev->max_sectors = ATA_MAX_SECTORS_LBA48;



	if (!(dev->horkage & ATA_HORKAGE_IPM)) {

		if (ata_id_has_hipm(dev->id))

			dev->flags |= ATA_DFLAG_HIPM;

		if (ata_id_has_dipm(dev->id))

			dev->flags |= ATA_DFLAG_DIPM;

	}



	if (dev->horkage & ATA_HORKAGE_DIAGNOSTIC) {

		/* Let the user know. We don't want to disallow opens for

		   rescue purposes, or in case the vendor is just a blithering
@@ -2126,6 +2304,13 @@ int ata_dev_configure(struct ata_device *dev) 
		dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_128,

					 dev->max_sectors);



	if (ata_dev_blacklisted(dev) & ATA_HORKAGE_IPM) {

		dev->horkage |= ATA_HORKAGE_IPM;



		/* reset link pm_policy for this port to no pm */

		ap->pm_policy = MAX_PERFORMANCE;

	}



	if (ap->ops->dev_config)

		ap->ops->dev_config(dev);
@@ -6362,6 +6547,12 @@ int ata_host_suspend(struct ata_host *host, pm_message_t mesg) 
{

	int rc;



	/*

	 * disable link pm on all ports before requesting

	 * any pm activity

	 */

	ata_lpm_enable(host);



	rc = ata_host_request_pm(host, mesg, 0, ATA_EHI_QUIET, 1);

	if (rc == 0)

		host->dev->power.power_state = mesg;
@@ -6384,6 +6575,9 @@ void ata_host_resume(struct ata_host *host) 
	ata_host_request_pm(host, PMSG_ON, ATA_EH_SOFTRESET,

			    ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 0);

	host->dev->power.power_state = PMSG_ON;



	/* reenable link pm */

	ata_lpm_disable(host);

}

#endif
@@ -6926,6 +7120,7 @@ int ata_host_register(struct ata_host *host, struct scsi_host_template *sht) 
		struct ata_port *ap = host->ports[i];



		ata_scsi_scan_host(ap, 1);

		ata_lpm_schedule(ap, ap->pm_policy);

	}



	return 0;
@@ -7322,7 +7517,6 @@ const struct ata_port_info ata_dummy_port_info = { 
 * likely to change as new drivers are added and updated.

 * Do not depend on ABI/API stability.

 */



EXPORT_SYMBOL_GPL(sata_deb_timing_normal);

EXPORT_SYMBOL_GPL(sata_deb_timing_hotplug);

EXPORT_SYMBOL_GPL(sata_deb_timing_long);

drivers/ata/libata-eh.c

+4 −0
Original line number Diff line number Diff line
@@ -2628,6 +2628,10 @@ int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset, 
			ehc->i.flags &= ~ATA_EHI_SETMODE;

		}



		if (ehc->i.action & ATA_EHI_LPM)

			ata_link_for_each_dev(dev, link)

				ata_dev_enable_pm(dev, ap->pm_policy);



		/* this link is okay now */

		ehc->i.flags = 0;

		continue;

drivers/ata/libata-scsi.c

+68 −0
Original line number Diff line number Diff line
@@ -110,6 +110,74 @@ static struct scsi_transport_template ata_scsi_transport_template = { 
};





static const struct {

	enum link_pm	value;

	const char	*name;

} link_pm_policy[] = {

	{ NOT_AVAILABLE, "max_performance" },

	{ MIN_POWER, "min_power" },

	{ MAX_PERFORMANCE, "max_performance" },

	{ MEDIUM_POWER, "medium_power" },

};



const char *ata_scsi_lpm_get(enum link_pm policy)

{

	int i;



	for (i = 0; i < ARRAY_SIZE(link_pm_policy); i++)

		if (link_pm_policy[i].value == policy)

			return link_pm_policy[i].name;



	return NULL;

}



static ssize_t ata_scsi_lpm_put(struct class_device *class_dev,

	const char *buf, size_t count)

{

	struct Scsi_Host *shost = class_to_shost(class_dev);

	struct ata_port *ap = ata_shost_to_port(shost);

	enum link_pm policy = 0;

	int i;



	/*

	 * we are skipping array location 0 on purpose - this

	 * is because a value of NOT_AVAILABLE is displayed

	 * to the user as max_performance, but when the user

	 * writes "max_performance", they actually want the

	 * value to match MAX_PERFORMANCE.

	 */

	for (i = 1; i < ARRAY_SIZE(link_pm_policy); i++) {

		const int len = strlen(link_pm_policy[i].name);

		if (strncmp(link_pm_policy[i].name, buf, len) == 0 &&

		   buf[len] == '\n') {

			policy = link_pm_policy[i].value;

			break;

		}

	}

	if (!policy)

		return -EINVAL;



	ata_lpm_schedule(ap, policy);

	return count;

}



static ssize_t

ata_scsi_lpm_show(struct class_device *class_dev, char *buf)

{

	struct Scsi_Host *shost = class_to_shost(class_dev);

	struct ata_port *ap = ata_shost_to_port(shost);

	const char *policy =

		ata_scsi_lpm_get(ap->pm_policy);



	if (!policy)

		return -EINVAL;



	return snprintf(buf, 23, "%s\n", policy);

}

CLASS_DEVICE_ATTR(link_power_management_policy, S_IRUGO | S_IWUSR,

		ata_scsi_lpm_show, ata_scsi_lpm_put);

EXPORT_SYMBOL_GPL(class_device_attr_link_power_management_policy);



static void ata_scsi_invalid_field(struct scsi_cmnd *cmd,

				   void (*done)(struct scsi_cmnd *))

{