[PATCH v2 01/10] ata: libahci: Ensure the host interrupt status bits are cleared

[Miquel Raynal <miquel.raynal@bootlin.com>]

ahci_multi_irqs_intr_hard() is going to be used as interrupt handler
to support SATA per-port interrupts. The current logic is to check and
clear the SATA port interrupt status register only. To avoid spurious
IRQs and interrupt storms, it will be needed to clear the port
interrupt bit in the host interrupt status register as well.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 drivers/ata/libahci.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index b5f57c69c487..66d4906a5013 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -1912,7 +1912,10 @@ static void ahci_port_intr(struct ata_port *ap)
 static irqreturn_t ahci_multi_irqs_intr_hard(int irq, void *dev_instance)
 {
 	struct ata_port *ap = dev_instance;
+	struct ata_host *host = ap->host;
+	struct ahci_host_priv *hpriv = host->private_data;
 	void __iomem *port_mmio = ahci_port_base(ap);
+	void __iomem *mmio = hpriv->mmio;
 	u32 status;
 
 	VPRINTK("ENTER\n");
@@ -1924,6 +1927,10 @@ static irqreturn_t ahci_multi_irqs_intr_hard(int irq, void *dev_instance)
 	ahci_handle_port_interrupt(ap, port_mmio, status);
 	spin_unlock(ap->lock);
 
+	spin_lock(&host->lock);
+	writel(BIT(ap->port_no), mmio + HOST_IRQ_STAT);
+	spin_unlock(&host->lock);
+
 	VPRINTK("EXIT\n");
 
 	return IRQ_HANDLED;
-- 
2.19.1