This is a note to let you know that I've just added the patch titled
xhci: Add quirk to workaround the errata seen on Cavium Thunder-X2 Soc
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
xhci-add-quirk-to-workaround-the-errata-seen-on-cavium-thunder-x2-soc.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 11644a7659529730eaf2f166efaabe7c3dc7af8c Mon Sep 17 00:00:00 2001
From: "Cherian, George" <George.Cherian@xxxxxxxxxx>
Date: Fri, 9 Nov 2018 17:21:22 +0200
Subject: xhci: Add quirk to workaround the errata seen on Cavium Thunder-X2 Soc
From: Cherian, George <George.Cherian@xxxxxxxxxx>
commit 11644a7659529730eaf2f166efaabe7c3dc7af8c upstream.
Implement workaround for ThunderX2 Errata-129 (documented in
CN99XX Known Issues" available at Cavium support site).
As per ThunderX2errata-129, USB 2 device may come up as USB 1
if a connection to a USB 1 device is followed by another connection to
a USB 2 device, the link will come up as USB 1 for the USB 2 device.
Resolution: Reset the PHY after the USB 1 device is disconnected.
The PHY reset sequence is done using private registers in XHCI register
space. After the PHY is reset we check for the PLL lock status and retry
the operation if it fails. From our tests, retrying 4 times is sufficient.
Add a new quirk flag XHCI_RESET_PLL_ON_DISCONNECT to invoke the workaround
in handle_xhci_port_status().
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: George Cherian <george.cherian@xxxxxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/host/xhci-pci.c | 5 +++++
drivers/usb/host/xhci-ring.c | 35 ++++++++++++++++++++++++++++++++++-
drivers/usb/host/xhci.h | 1 +
3 files changed, 40 insertions(+), 1 deletion(-)
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -236,6 +236,11 @@ static void xhci_pci_quirks(struct devic
if (pdev->vendor == PCI_VENDOR_ID_TI && pdev->device == 0x8241)
xhci->quirks |= XHCI_LIMIT_ENDPOINT_INTERVAL_7;
+ if ((pdev->vendor == PCI_VENDOR_ID_BROADCOM ||
+ pdev->vendor == PCI_VENDOR_ID_CAVIUM) &&
+ pdev->device == 0x9026)
+ xhci->quirks |= XHCI_RESET_PLL_ON_DISCONNECT;
+
if (xhci->quirks & XHCI_RESET_ON_RESUME)
xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
"QUIRK: Resetting on resume");
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -1568,6 +1568,35 @@ static void handle_device_notification(s
usb_wakeup_notification(udev->parent, udev->portnum);
}
+/*
+ * Quirk hanlder for errata seen on Cavium ThunderX2 processor XHCI
+ * Controller.
+ * As per ThunderX2errata-129 USB 2 device may come up as USB 1
+ * If a connection to a USB 1 device is followed by another connection
+ * to a USB 2 device.
+ *
+ * Reset the PHY after the USB device is disconnected if device speed
+ * is less than HCD_USB3.
+ * Retry the reset sequence max of 4 times checking the PLL lock status.
+ *
+ */
+static void xhci_cavium_reset_phy_quirk(struct xhci_hcd *xhci)
+{
+ struct usb_hcd *hcd = xhci_to_hcd(xhci);
+ u32 pll_lock_check;
+ u32 retry_count = 4;
+
+ do {
+ /* Assert PHY reset */
+ writel(0x6F, hcd->regs + 0x1048);
+ udelay(10);
+ /* De-assert the PHY reset */
+ writel(0x7F, hcd->regs + 0x1048);
+ udelay(200);
+ pll_lock_check = readl(hcd->regs + 0x1070);
+ } while (!(pll_lock_check & 0x1) && --retry_count);
+}
+
static void handle_port_status(struct xhci_hcd *xhci,
union xhci_trb *event)
{
@@ -1725,9 +1754,13 @@ static void handle_port_status(struct xh
goto cleanup;
}
- if (hcd->speed < HCD_USB3)
+ if (hcd->speed < HCD_USB3) {
xhci_test_and_clear_bit(xhci, port_array, faked_port_index,
PORT_PLC);
+ if ((xhci->quirks & XHCI_RESET_PLL_ON_DISCONNECT) &&
+ (portsc & PORT_CSC) && !(portsc & PORT_CONNECT))
+ xhci_cavium_reset_phy_quirk(xhci);
+ }
cleanup:
/* Update event ring dequeue pointer before dropping the lock */
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1838,6 +1838,7 @@ struct xhci_hcd {
#define XHCI_HW_LPM_DISABLE BIT_ULL(29)
#define XHCI_SUSPEND_DELAY BIT_ULL(30)
#define XHCI_INTEL_USB_ROLE_SW BIT_ULL(31)
+#define XHCI_RESET_PLL_ON_DISCONNECT BIT_ULL(34)
unsigned int num_active_eps;
unsigned int limit_active_eps;
Patches currently in stable-queue which might be from George.Cherian@xxxxxxxxxx are
queue-4.14/xhci-add-quirk-to-workaround-the-errata-seen-on-cavium-thunder-x2-soc.patch
queue-4.14/xhci-allow-more-than-32-quirks.patch
