diff options
Diffstat (limited to 'drivers/usb/host/pci-quirks.c')
-rw-r--r-- | drivers/usb/host/pci-quirks.c | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c index f16c59d5f487..fd930618c28f 100644 --- a/drivers/usb/host/pci-quirks.c +++ b/drivers/usb/host/pci-quirks.c @@ -69,6 +69,9 @@ #define NB_PIF0_PWRDOWN_0 0x01100012 #define NB_PIF0_PWRDOWN_1 0x01100013 +#define USB_INTEL_XUSB2PR 0xD0 +#define USB_INTEL_USB3_PSSEN 0xD8 + static struct amd_chipset_info { struct pci_dev *nb_dev; struct pci_dev *smbus_dev; @@ -673,6 +676,64 @@ static int handshake(void __iomem *ptr, u32 mask, u32 done, return -ETIMEDOUT; } +bool usb_is_intel_switchable_xhci(struct pci_dev *pdev) +{ + return pdev->class == PCI_CLASS_SERIAL_USB_XHCI && + pdev->vendor == PCI_VENDOR_ID_INTEL && + pdev->device == PCI_DEVICE_ID_INTEL_PANTHERPOINT_XHCI; +} +EXPORT_SYMBOL_GPL(usb_is_intel_switchable_xhci); + +/* + * Intel's Panther Point chipset has two host controllers (EHCI and xHCI) that + * share some number of ports. These ports can be switched between either + * controller. Not all of the ports under the EHCI host controller may be + * switchable. + * + * The ports should be switched over to xHCI before PCI probes for any device + * start. This avoids active devices under EHCI being disconnected during the + * port switchover, which could cause loss of data on USB storage devices, or + * failed boot when the root file system is on a USB mass storage device and is + * enumerated under EHCI first. + * + * We write into the xHC's PCI configuration space in some Intel-specific + * registers to switch the ports over. The USB 3.0 terminations and the USB + * 2.0 data wires are switched separately. We want to enable the SuperSpeed + * terminations before switching the USB 2.0 wires over, so that USB 3.0 + * devices connect at SuperSpeed, rather than at USB 2.0 speeds. + */ +void usb_enable_xhci_ports(struct pci_dev *xhci_pdev) +{ + u32 ports_available; + + ports_available = 0xffffffff; + /* Write USB3_PSSEN, the USB 3.0 Port SuperSpeed Enable + * Register, to turn on SuperSpeed terminations for all + * available ports. + */ + pci_write_config_dword(xhci_pdev, USB_INTEL_USB3_PSSEN, + cpu_to_le32(ports_available)); + + pci_read_config_dword(xhci_pdev, USB_INTEL_USB3_PSSEN, + &ports_available); + dev_dbg(&xhci_pdev->dev, "USB 3.0 ports that are now enabled " + "under xHCI: 0x%x\n", ports_available); + + ports_available = 0xffffffff; + /* Write XUSB2PR, the xHC USB 2.0 Port Routing Register, to + * switch the USB 2.0 power and data lines over to the xHCI + * host. + */ + pci_write_config_dword(xhci_pdev, USB_INTEL_XUSB2PR, + cpu_to_le32(ports_available)); + + pci_read_config_dword(xhci_pdev, USB_INTEL_XUSB2PR, + &ports_available); + dev_dbg(&xhci_pdev->dev, "USB 2.0 ports that are now switched over " + "to xHCI: 0x%x\n", ports_available); +} +EXPORT_SYMBOL_GPL(usb_enable_xhci_ports); + /** * PCI Quirks for xHCI. * @@ -732,6 +793,8 @@ static void __devinit quirk_usb_handoff_xhci(struct pci_dev *pdev) writel(XHCI_LEGACY_DISABLE_SMI, base + ext_cap_offset + XHCI_LEGACY_CONTROL_OFFSET); + if (usb_is_intel_switchable_xhci(pdev)) + usb_enable_xhci_ports(pdev); hc_init: op_reg_base = base + XHCI_HC_LENGTH(readl(base)); |