1 files changed, 36 insertions, 14 deletions

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index c477685315a5..dae5607e1115 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -1119,6 +1119,17 @@ static bool ahci_broken_online(struct pci_dev *pdev)
 	return pdev->bus->number == (val >> 8) && pdev->devfn == (val & 0xff);
 }
 
+static bool ahci_broken_devslp(struct pci_dev *pdev)
+{
+	/* device with broken DEVSLP but still showing SDS capability */
+	static const struct pci_device_id ids[] = {
+		{ PCI_VDEVICE(INTEL, 0x0f23)}, /* Valleyview SoC */
+		{}
+	};
+
+	return pci_match_id(ids, pdev);
+}
+
 #ifdef CONFIG_ATA_ACPI
 static void ahci_gtf_filter_workaround(struct ata_host *host)
 {
@@ -1168,9 +1179,9 @@ static inline void ahci_gtf_filter_workaround(struct ata_host *host)
 #endif
 
 static int ahci_init_interrupts(struct pci_dev *pdev, unsigned int n_ports,
-			 struct ahci_host_priv *hpriv)
+				struct ahci_host_priv *hpriv)
 {
-	int nvec;
+	int rc, nvec;
 
 	if (hpriv->flags & AHCI_HFLAG_NO_MSI)
 		goto intx;
@@ -1187,12 +1198,19 @@ static int ahci_init_interrupts(struct pci_dev *pdev, unsigned int n_ports,
 	if (nvec < n_ports)
 		goto single_msi;
 
-	nvec = pci_enable_msi_range(pdev, nvec, nvec);
-	if (nvec == -ENOSPC)
+	rc = pci_enable_msi_exact(pdev, nvec);
+	if (rc == -ENOSPC)
 		goto single_msi;
-	else if (nvec < 0)
+	else if (rc < 0)
 		goto intx;
 
+	/* fallback to single MSI mode if the controller enforced MRSM mode */
+	if (readl(hpriv->mmio + HOST_CTL) & HOST_MRSM) {
+		pci_disable_msi(pdev);
+		printk(KERN_INFO "ahci: MRSM is on, fallback to single MSI\n");
+		goto single_msi;
+	}
+
 	return nvec;
 
 single_msi:
@@ -1236,18 +1254,18 @@ int ahci_host_activate(struct ata_host *host, int irq, unsigned int n_msis)
 		return rc;
 
 	for (i = 0; i < host->n_ports; i++) {
-		const char* desc;
 		struct ahci_port_priv *pp = host->ports[i]->private_data;
 
-		/* pp is NULL for dummy ports */
-		if (pp)
-			desc = pp->irq_desc;
-		else
-			desc = dev_driver_string(host->dev);
+		/* Do not receive interrupts sent by dummy ports */
+		if (!pp) {
+			disable_irq(irq + i);
+			continue;
+		}
 
-		rc = devm_request_threaded_irq(host->dev,
-			irq + i, ahci_hw_interrupt, ahci_thread_fn, IRQF_SHARED,
-			desc, host->ports[i]);
+		rc = devm_request_threaded_irq(host->dev, irq + i,
+					       ahci_hw_interrupt,
+					       ahci_thread_fn, IRQF_SHARED,
+					       pp->irq_desc, host->ports[i]);
 		if (rc)
 			goto out_free_irqs;
 	}
@@ -1361,6 +1379,10 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	hpriv->mmio = pcim_iomap_table(pdev)[ahci_pci_bar];
 
+	/* must set flag prior to save config in order to take effect */
+	if (ahci_broken_devslp(pdev))
+		hpriv->flags |= AHCI_HFLAG_NO_DEVSLP;
+
 	/* save initial config */
 	ahci_pci_save_initial_config(pdev, hpriv);