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

5 files changed, 424 insertions, 3 deletions

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index c8ab947cf359..ed9b407e42d4 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -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;
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index e512903b8dbb..63035d71a61a 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -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);
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index ec55d63cf20e..fefea7470e51 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -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;
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index f752eddc19ed..93bd36c19690 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -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 *))
 {
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 90df58a3edc9..0e6cf3a484dc 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -101,6 +101,8 @@ extern int sata_link_init_spd(struct ata_link *link);
 extern int ata_task_ioctl(struct scsi_device *scsidev, void __user *arg);
 extern int ata_cmd_ioctl(struct scsi_device *scsidev, void __user *arg);
 extern struct ata_port *ata_port_alloc(struct ata_host *host);
+extern void ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy);
+extern void ata_lpm_schedule(struct ata_port *ap, enum link_pm);
 
 /* libata-acpi.c */
 #ifdef CONFIG_ATA_ACPI