[PATCH v4 1/2] USB: Try MSI first before line IRQ for Intel PCIe USB3 HCD

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



We have a PCI USB xhci host controller on a new platform. It have no
line IRQ definition in BIOS. So the Linux driver refuses to initial this
controller. But Windows works well for it depending on MSI.

Actually, Linux also can work for MSI. This patch skips the first line
IRQ checking for our HCD in usb-core pci probe, then try to enable MSI
firstly. That make this HCD works well under Linux.

Thanks for Sarah's suggestion and review for this patch.

Signed-off-by: Alex Shi <alex.shi@xxxxxxxxx>
---
 drivers/usb/core/hcd-pci.c  |    3 ++-
 drivers/usb/core/hcd.c      |    8 ++++++--
 drivers/usb/host/xhci-pci.c |    6 ++++++
 drivers/usb/host/xhci.c     |    5 +++++
 include/linux/usb/hcd.h     |    1 +
 5 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c
index a004db3..266ea2f 100644
--- a/drivers/usb/core/hcd-pci.c
+++ b/drivers/usb/core/hcd-pci.c
@@ -187,7 +187,8 @@ int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
 		return -ENODEV;
 	dev->current_state = PCI_D0;
 
-	if (!dev->irq) {
+	/* skip irq check if hcd wants MSI firstly. */
+	if (!(driver->flags & HCD_MSI_FIRST) && !dev->irq) {
 		dev_err(&dev->dev,
 			"Found HC with no IRQ.  Check BIOS/PCI %s setup!\n",
 			pci_name(dev));
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 13222d3..9dd8098 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -2466,8 +2466,12 @@ int usb_add_hcd(struct usb_hcd *hcd,
 			&& device_can_wakeup(&hcd->self.root_hub->dev))
 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
 
-	/* enable irqs just before we start the controller */
-	if (usb_hcd_is_primary_hcd(hcd)) {
+	/* enable irqs just before we start the controller. But Intel USB3
+	 * hcd can't do this here on some platform, they will do it in
+	 * following driver->start();
+	 */
+	if (usb_hcd_is_primary_hcd(hcd) &&
+			!(hcd->driver->flags & HCD_MSI_FIRST)) {
 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
 		if (retval)
 			goto err_request_irq;
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index ef98b38..d453cb8 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -136,6 +136,12 @@ static int xhci_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
 	struct usb_hcd *hcd;
 
 	driver = (struct hc_driver *)id->driver_data;
+
+	/* stop line IRQ checking in xhci_hcd_pci_probe. */
+	if (dev->vendor == PCI_VENDOR_ID_INTEL &&
+			dev->device == PCI_DEVICE_ID_INTEL_PANTHERPOINT_XHCI)
+		driver->flags |= HCD_MSI_FIRST;
+
 	/* Register the USB 2.0 roothub.
 	 * FIXME: USB core must know to register the USB 2.0 roothub first.
 	 * This is sort of silly, because we could just set the HCD driver flags
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index a1afb7c..05cf62d 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -352,6 +352,11 @@ static int xhci_try_enable_msi(struct usb_hcd *hcd)
 		/* hcd->irq is -1, we have MSI */
 		return 0;
 
+	if (!pdev->irq) {
+		xhci_err(xhci, "No msi-x/msi found and no IRQ in BIOS\n");
+		return -EINVAL;
+	}
+
 	/* fall back to legacy interrupt*/
 	ret = request_irq(pdev->irq, &usb_hcd_irq, IRQF_SHARED,
 			hcd->irq_descr, hcd);
diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h
index 03354d5..ea1637b 100644
--- a/include/linux/usb/hcd.h
+++ b/include/linux/usb/hcd.h
@@ -212,6 +212,7 @@ struct hc_driver {
 #define	HCD_MEMORY	0x0001		/* HC regs use memory (else I/O) */
 #define	HCD_LOCAL_MEM	0x0002		/* HC needs local memory */
 #define	HCD_SHARED	0x0004		/* Two (or more) usb_hcds share HW */
+#define	HCD_MSI_FIRST	0x0008		/* Try to get MSI first, PCI only */
 #define	HCD_USB11	0x0010		/* USB 1.1 */
 #define	HCD_USB2	0x0020		/* USB 2.0 */
 #define	HCD_USB3	0x0040		/* USB 3.0 */
-- 
1.6.3.3

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux