[PATCH 1/3] xhci: add restart quirk for Intel Wildcatpoint PCH

[PATCH 1/3] xhci: add restart quirk for Intel Wildcatpoint PCH

[Mathias Nyman]

xHC in Wildcatpoint-LP PCH is similar to LynxPoint-LP and need the
same quirks to prevent machines from spurious restart while
shutting them down.

Reported-by: Hasan Mahmood <hasan.mahm@gmail.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
---
 drivers/usb/host/xhci-pci.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index d7b0f97..314179b 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -45,6 +45,7 @@
 
 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_XHCI	0x8c31
 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_XHCI	0x9c31
+#define PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_XHCI	0x9cb1
 #define PCI_DEVICE_ID_INTEL_CHERRYVIEW_XHCI		0x22b5
 #define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_XHCI		0xa12f
 #define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_XHCI	0x9d2f
@@ -153,7 +154,8 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
 		xhci->quirks |= XHCI_SPURIOUS_REBOOT;
 	}
 	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
-		pdev->device == PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_XHCI) {
+		(pdev->device == PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_XHCI ||
+		 pdev->device == PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_XHCI)) {
 		xhci->quirks |= XHCI_SPURIOUS_REBOOT;
 		xhci->quirks |= XHCI_SPURIOUS_WAKEUP;
 	}
-- 
1.9.1

[PATCH 2/3] xhci: workaround for hosts missing CAS bit

[Mathias Nyman]

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 <mathias.nyman@linux.intel.com>
CC: <stable@vger.kernel.org>
---
 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(+)

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 730b9fd..c047362 100644
--- 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
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 314179b..e96ae80 100644
--- 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 device *dev, struct xhci_hcd *xhci)
 		 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;
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index b2c1dc5..f945380 100644
--- 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 */
-- 
1.9.1

[PATCH 3/3] xhci: use default USB_RESUME_TIMEOUT when resuming ports.

[Mathias Nyman]

USB2 host inititated resume, and system suspend bus resume
need to use the same USB_RESUME_TIMEOUT as elsewhere.

This resolves a device disconnect issue at system resume seen
on Intel Braswell and Apollolake, but is in no way limited to
those platforms.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
CC: <stable@vger.kernel.org>
---
 drivers/usb/host/xhci-hub.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index c047362..0ef1690 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -1166,7 +1166,7 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 				xhci_set_link_state(xhci, port_array, wIndex,
 							XDEV_RESUME);
 				spin_unlock_irqrestore(&xhci->lock, flags);
-				msleep(20);
+				msleep(USB_RESUME_TIMEOUT);
 				spin_lock_irqsave(&xhci->lock, flags);
 				xhci_set_link_state(xhci, port_array, wIndex,
 							XDEV_U0);
@@ -1447,7 +1447,7 @@ int xhci_bus_resume(struct usb_hcd *hcd)
 
 	if (need_usb2_u3_exit) {
 		spin_unlock_irqrestore(&xhci->lock, flags);
-		msleep(20);
+		msleep(USB_RESUME_TIMEOUT);
 		spin_lock_irqsave(&xhci->lock, flags);
 	}
 
-- 
1.9.1