This patch adds the support to handle HOST_IRQ_STAT as edge trigger
latch.
Signed-off-by: Suman Tripathi <stripathi@xxxxxxx>
---
drivers/ata/ahci.h | 2 ++
drivers/ata/libahci.c | 93 +++++++++++++++++++++++++++++++++++++++------------
2 files changed, 73 insertions(+), 22 deletions(-)
diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
index 71262e0..2df2237 100644
--- a/drivers/ata/ahci.h
+++ b/drivers/ata/ahci.h
@@ -238,6 +238,8 @@ enum {
AHCI_HFLAG_MULTI_MSI = (1 << 16), /* multiple PCI MSIs */
AHCI_HFLAG_NO_DEVSLP = (1 << 17), /* no device sleep */
AHCI_HFLAG_NO_FBS = (1 << 18), /* no FBS */
+ AHCI_HFLAG_EDGE_TRIG_IRQ = (1 << 19), /* HOST_IRQ_STAT behaves as
+ Edge Triggered */
/* ap->flags bits */
diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index 61a9c07..6f1a603 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -1826,27 +1826,9 @@ 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)
{
- struct ata_host *host = dev_instance;
- struct ahci_host_priv *hpriv;
unsigned int i, handled = 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);
for (i = 0; i < host->n_ports; i++) {
struct ata_port *ap;
@@ -1864,10 +1846,36 @@ static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance)
dev_warn(host->dev,
"interrupt on disabled port %u\n", i);
}
-
handled = 1;
}
+ return handled;
+}
+
+static irqreturn_t ahci_level_trig_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;
* otherwise, it will raise a spurious interrupt after each
@@ -1877,13 +1885,51 @@ static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance)
* Also, use the unmasked value to clear interrupt as spurious
* pending event on a dummy port might cause screaming IRQ.
*/
+
+ writel(irq_stat, mmio + HOST_IRQ_STAT);
+
+ spin_unlock(&host->lock);
+
+ VPRINTK("EXIT\n");
+
+ return IRQ_RETVAL(rc);
+}
+
+static irqreturn_t ahci_edge_trig_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);
+
+ /*
+ * 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);
+ rc = ahci_handle_port_intr(host, irq_masked);
+
spin_unlock(&host->lock);
VPRINTK("EXIT\n");
- return IRQ_RETVAL(handled);
+ return IRQ_RETVAL(rc);
}
unsigned int ahci_qc_issue(struct ata_queued_cmd *qc)
@@ -2486,8 +2532,11 @@ int ahci_host_activate(struct ata_host *host, int irq,
if (hpriv->flags & AHCI_HFLAG_MULTI_MSI)
rc = ahci_host_activate_multi_irqs(host, irq, sht);
+ else if (hpriv->flags & AHCI_HFLAG_EDGE_TRIG_IRQ)
+ rc = ata_host_activate(host, irq, ahci_edge_trig_intr,
+ IRQF_SHARED, sht);
else
- rc = ata_host_activate(host, irq, ahci_single_irq_intr,
+ rc = ata_host_activate(host, irq, ahci_level_trig_intr,
IRQF_SHARED, sht);
return rc;
}
--
1.8.2.1
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