Commit 5903b164 authored by Suman Tripathi's avatar Suman Tripathi Committed by Tejun Heo
Browse files

libahci: Add support to handle HOST_IRQ_STAT as edge trigger latch. 



This patch adds the support to handle HOST_IRQ_STAT as edge trigger
latch.

Signed-off-by: default avatarSuman Tripathi <stripathi@apm.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent a129db89

drivers/ata/ahci.h

+2 −0
Original line number Diff line number Diff line
@@ -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_IRQ		= (1 << 19), /* HOST_IRQ_STAT behaves as

							Edge Triggered */



	/* ap->flags bits */

drivers/ata/libahci.c

+40 −0
Original line number Diff line number Diff line
@@ -1853,6 +1853,43 @@ static u32 ahci_handle_port_intr(struct ata_host *host, u32 irq_masked) 
	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 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(rc);

}



static irqreturn_t ahci_single_level_irq_intr(int irq, void *dev_instance)

{

	struct ata_host *host = dev_instance;
@@ -2495,6 +2532,9 @@ 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_IRQ)

		rc = ata_host_activate(host, irq, ahci_single_edge_irq_intr,

				       IRQF_SHARED, sht);

	else

		rc = ata_host_activate(host, irq, ahci_single_level_irq_intr,

				       IRQF_SHARED, sht);