1 files changed, 76 insertions, 29 deletions

diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index 287c4ba0219f..d256a66158be 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -1825,11 +1825,38 @@ static irqreturn_t ahci_multi_irqs_intr(int irq, void *dev_instance)
 	return IRQ_WAKE_THREAD;
 }
 
-static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance)
+static u32 ahci_handle_port_intr(struct ata_host *host, u32 irq_masked)
+{
+	unsigned int i, handled = 0;
+
+	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_warn(host->dev,
+					 "interrupt on disabled port %u\n", i);
+		}
+
+		handled = 1;
+	}
+
+	return handled;
+}
+
+static irqreturn_t ahci_single_edge_irq_intr(int irq, void *dev_instance)
 {
 	struct ata_host *host = dev_instance;
 	struct ahci_host_priv *hpriv;
-	unsigned int i, handled = 0;
+	unsigned int rc = 0;
 	void __iomem *mmio;
 	u32 irq_stat, irq_masked;
 
@@ -1847,25 +1874,44 @@ static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance)
 
 	spin_lock(&host->lock);
 
-	for (i = 0; i < host->n_ports; i++) {
-		struct ata_port *ap;
+	/*
+	 * HOST_IRQ_STAT behaves as edge triggered latch meaning that
+	 * it should be cleared before all the port events are cleared.
+	 */
+	writel(irq_stat, mmio + HOST_IRQ_STAT);
 
-		if (!(irq_masked & (1 << i)))
-			continue;
+	rc = ahci_handle_port_intr(host, irq_masked);
 
-		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_warn(host->dev,
-					 "interrupt on disabled port %u\n", i);
-		}
+	spin_unlock(&host->lock);
 
-		handled = 1;
-	}
+	VPRINTK("EXIT\n");
+
+	return IRQ_RETVAL(rc);
+}
+
+static irqreturn_t ahci_single_level_irq_intr(int irq, void *dev_instance)
+{
+	struct ata_host *host = dev_instance;
+	struct ahci_host_priv *hpriv;
+	unsigned int rc = 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);
+
+	rc = ahci_handle_port_intr(host, irq_masked);
 
 	/* HOST_IRQ_STAT behaves as level triggered latch meaning that
 	 * it should be cleared after all the port events are cleared;
@@ -1882,7 +1928,7 @@ static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance)
 
 	VPRINTK("EXIT\n");
 
-	return IRQ_RETVAL(handled);
+	return IRQ_RETVAL(rc);
 }
 
 unsigned int ahci_qc_issue(struct ata_queued_cmd *qc)
@@ -2297,7 +2343,7 @@ static int ahci_port_start(struct ata_port *ap)
 	/*
 	 * Switch to per-port locking in case each port has its own MSI vector.
 	 */
-	if ((hpriv->flags & AHCI_HFLAG_MULTI_MSI)) {
+	if (hpriv->flags & AHCI_HFLAG_MULTI_MSI) {
 		spin_lock_init(&pp->lock);
 		ap->lock = &pp->lock;
 	}
@@ -2425,7 +2471,10 @@ static int ahci_host_activate_multi_irqs(struct ata_host *host, int irq,
 	rc = ata_host_start(host);
 	if (rc)
 		return rc;
-
+	/*
+	 * Requests IRQs according to AHCI-1.1 when multiple MSIs were
+	 * allocated. That is one MSI per port, starting from @irq.
+	 */
 	for (i = 0; i < host->n_ports; i++) {
 		struct ahci_port_priv *pp = host->ports[i]->private_data;
 
@@ -2464,29 +2513,27 @@ out_free_irqs:
 /**
  *	ahci_host_activate - start AHCI host, request IRQs and register it
  *	@host: target ATA host
- *	@irq: base IRQ number to request
  *	@sht: scsi_host_template to use when registering the host
  *
- *	Similar to ata_host_activate, but requests IRQs according to AHCI-1.1
- *	when multiple MSIs were allocated. That is one MSI per port, starting
- *	from @irq.
- *
  *	LOCKING:
  *	Inherited from calling layer (may sleep).
  *
  *	RETURNS:
  *	0 on success, -errno otherwise.
  */
-int ahci_host_activate(struct ata_host *host, int irq,
-		       struct scsi_host_template *sht)
+int ahci_host_activate(struct ata_host *host, struct scsi_host_template *sht)
 {
 	struct ahci_host_priv *hpriv = host->private_data;
+	int irq = hpriv->irq;
 	int rc;
 
 	if (hpriv->flags & AHCI_HFLAG_MULTI_MSI)
 		rc = ahci_host_activate_multi_irqs(host, irq, sht);
+	else if (hpriv->flags & AHCI_HFLAG_EDGE_IRQ)
+		rc = ata_host_activate(host, irq, ahci_single_edge_irq_intr,
+				       IRQF_SHARED, sht);
 	else
-		rc = ata_host_activate(host, irq, ahci_single_irq_intr,
+		rc = ata_host_activate(host, irq, ahci_single_level_irq_intr,
 				       IRQF_SHARED, sht);
 	return rc;
 }