Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754076AbcKILUJ (ORCPT ); Wed, 9 Nov 2016 06:20:09 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:55232 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933945AbcKILJk (ORCPT ); Wed, 9 Nov 2016 06:09:40 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mathias Nyman Subject: [PATCH 4.8 062/138] xhci: workaround for hosts missing CAS bit Date: Wed, 9 Nov 2016 11:45:45 +0100 Message-Id: <20161109102847.619721555@linuxfoundation.org> X-Mailer: git-send-email 2.10.2 In-Reply-To: <20161109102844.808685475@linuxfoundation.org> References: <20161109102844.808685475@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4303 Lines: 126 4.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mathias Nyman commit 346e99736c3ce328fd42d678343b70243aca5f36 upstream. If a device is unplugged and replugged during Sx system suspend some Intel xHC hosts will overwrite the CAS (Cold attach status) flag and no device connection is noticed in resume. A device in this state can be identified in resume if its link state is in polling or compliance mode, and the current connect status is 0. A device in this state needs to be warm reset. Intel 100/c230 series PCH specification update Doc #332692-006 Errata #8 Observed on Cherryview and Apollolake as they go into compliance mode if LFPS times out during polling, and re-plugged devices are not discovered at resume. Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-hub.c | 37 +++++++++++++++++++++++++++++++++++++ drivers/usb/host/xhci-pci.c | 6 ++++++ drivers/usb/host/xhci.h | 3 +++ 3 files changed, 46 insertions(+) --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -1355,6 +1355,35 @@ int xhci_bus_suspend(struct usb_hcd *hcd return 0; } +/* + * Workaround for missing Cold Attach Status (CAS) if device re-plugged in S3. + * warm reset a USB3 device stuck in polling or compliance mode after resume. + * See Intel 100/c230 series PCH specification update Doc #332692-006 Errata #8 + */ +static bool xhci_port_missing_cas_quirk(int port_index, + __le32 __iomem **port_array) +{ + u32 portsc; + + portsc = readl(port_array[port_index]); + + /* if any of these are set we are not stuck */ + if (portsc & (PORT_CONNECT | PORT_CAS)) + return false; + + if (((portsc & PORT_PLS_MASK) != XDEV_POLLING) && + ((portsc & PORT_PLS_MASK) != XDEV_COMP_MODE)) + return false; + + /* clear wakeup/change bits, and do a warm port reset */ + portsc &= ~(PORT_RWC_BITS | PORT_CEC | PORT_WAKE_BITS); + portsc |= PORT_WR; + writel(portsc, port_array[port_index]); + /* flush write */ + readl(port_array[port_index]); + return true; +} + int xhci_bus_resume(struct usb_hcd *hcd) { struct xhci_hcd *xhci = hcd_to_xhci(hcd); @@ -1392,6 +1421,14 @@ int xhci_bus_resume(struct usb_hcd *hcd) u32 temp; temp = readl(port_array[port_index]); + + /* warm reset CAS limited ports stuck in polling/compliance */ + if ((xhci->quirks & XHCI_MISSING_CAS) && + (hcd->speed >= HCD_USB3) && + xhci_port_missing_cas_quirk(port_index, port_array)) { + xhci_dbg(xhci, "reset stuck port %d\n", port_index); + continue; + } if (DEV_SUPERSPEED_ANY(temp)) temp &= ~(PORT_RWC_BITS | PORT_CEC | PORT_WAKE_BITS); else --- a/drivers/usb/host/xhci-pci.c +++ b/drivers/usb/host/xhci-pci.c @@ -51,6 +51,7 @@ #define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_XHCI 0x9d2f #define PCI_DEVICE_ID_INTEL_BROXTON_M_XHCI 0x0aa8 #define PCI_DEVICE_ID_INTEL_BROXTON_B_XHCI 0x1aa8 +#define PCI_DEVICE_ID_INTEL_APL_XHCI 0x5aa8 static const char hcd_name[] = "xhci_hcd"; @@ -171,6 +172,11 @@ static void xhci_pci_quirks(struct devic pdev->device == PCI_DEVICE_ID_INTEL_CHERRYVIEW_XHCI) { xhci->quirks |= XHCI_SSIC_PORT_UNUSED; } + if (pdev->vendor == PCI_VENDOR_ID_INTEL && + (pdev->device == PCI_DEVICE_ID_INTEL_CHERRYVIEW_XHCI || + pdev->device == PCI_DEVICE_ID_INTEL_APL_XHCI)) + xhci->quirks |= XHCI_MISSING_CAS; + if (pdev->vendor == PCI_VENDOR_ID_ETRON && pdev->device == PCI_DEVICE_ID_EJ168) { xhci->quirks |= XHCI_RESET_ON_RESUME; --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -314,6 +314,8 @@ struct xhci_op_regs { #define XDEV_U2 (0x2 << 5) #define XDEV_U3 (0x3 << 5) #define XDEV_INACTIVE (0x6 << 5) +#define XDEV_POLLING (0x7 << 5) +#define XDEV_COMP_MODE (0xa << 5) #define XDEV_RESUME (0xf << 5) /* true: port has power (see HCC_PPC) */ #define PORT_POWER (1 << 9) @@ -1653,6 +1655,7 @@ struct xhci_hcd { #define XHCI_MTK_HOST (1 << 21) #define XHCI_SSIC_PORT_UNUSED (1 << 22) #define XHCI_NO_64BIT_SUPPORT (1 << 23) +#define XHCI_MISSING_CAS (1 << 24) unsigned int num_active_eps; unsigned int limit_active_eps; /* There are two roothubs to keep track of bus suspend info for */