+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;
+}
+