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authorLinus Torvalds <torvalds@linux-foundation.org>2017-08-11 00:52:45 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2017-08-11 00:52:45 +0300
commit4e082e9ba7cdd7466b1ea81527feb93f4da8c580 (patch)
tree68092acc840dc1df09813b2808a88fc7b0847a26 /drivers
parent26273939ace935dd7553b31d279eab30b40f7b9a (diff)
parent8466489ef5ba48272ba4fa4ea9f8f403306de4c7 (diff)
downloadlinux-4e082e9ba7cdd7466b1ea81527feb93f4da8c580.tar.xz
Merge tag 'pci-v4.13-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI fix from Bjorn Helgaas: "Work around Renesas uPD72020x 32-bit DMA issue" * tag 'pci-v4.13-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: xhci: Reset Renesas uPD72020x USB controller for 32-bit DMA issue PCI: Add pci_reset_function_locked()
Diffstat (limited to 'drivers')
-rw-r--r--drivers/pci/pci.c35
-rw-r--r--drivers/usb/host/pci-quirks.c20
-rw-r--r--drivers/usb/host/pci-quirks.h1
-rw-r--r--drivers/usb/host/xhci-pci.c7
4 files changed, 63 insertions, 0 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index af0cc3456dc1..b4b7eab29400 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4260,6 +4260,41 @@ int pci_reset_function(struct pci_dev *dev)
EXPORT_SYMBOL_GPL(pci_reset_function);
/**
+ * pci_reset_function_locked - quiesce and reset a PCI device function
+ * @dev: PCI device to reset
+ *
+ * Some devices allow an individual function to be reset without affecting
+ * other functions in the same device. The PCI device must be responsive
+ * to PCI config space in order to use this function.
+ *
+ * This function does not just reset the PCI portion of a device, but
+ * clears all the state associated with the device. This function differs
+ * from __pci_reset_function() in that it saves and restores device state
+ * over the reset. It also differs from pci_reset_function() in that it
+ * requires the PCI device lock to be held.
+ *
+ * Returns 0 if the device function was successfully reset or negative if the
+ * device doesn't support resetting a single function.
+ */
+int pci_reset_function_locked(struct pci_dev *dev)
+{
+ int rc;
+
+ rc = pci_probe_reset_function(dev);
+ if (rc)
+ return rc;
+
+ pci_dev_save_and_disable(dev);
+
+ rc = __pci_reset_function_locked(dev);
+
+ pci_dev_restore(dev);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(pci_reset_function_locked);
+
+/**
* pci_try_reset_function - quiesce and reset a PCI device function
* @dev: PCI device to reset
*
diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
index c8989c62a262..858fefd67ebe 100644
--- a/drivers/usb/host/pci-quirks.c
+++ b/drivers/usb/host/pci-quirks.c
@@ -1150,3 +1150,23 @@ static void quirk_usb_early_handoff(struct pci_dev *pdev)
}
DECLARE_PCI_FIXUP_CLASS_FINAL(PCI_ANY_ID, PCI_ANY_ID,
PCI_CLASS_SERIAL_USB, 8, quirk_usb_early_handoff);
+
+bool usb_xhci_needs_pci_reset(struct pci_dev *pdev)
+{
+ /*
+ * Our dear uPD72020{1,2} friend only partially resets when
+ * asked to via the XHCI interface, and may end up doing DMA
+ * at the wrong addresses, as it keeps the top 32bit of some
+ * addresses from its previous programming under obscure
+ * circumstances.
+ * Give it a good wack at probe time. Unfortunately, this
+ * needs to happen before we've had a chance to discover any
+ * quirk, or the system will be in a rather bad state.
+ */
+ if (pdev->vendor == PCI_VENDOR_ID_RENESAS &&
+ (pdev->device == 0x0014 || pdev->device == 0x0015))
+ return true;
+
+ return false;
+}
+EXPORT_SYMBOL_GPL(usb_xhci_needs_pci_reset);
diff --git a/drivers/usb/host/pci-quirks.h b/drivers/usb/host/pci-quirks.h
index 655994480198..5582cbafecd4 100644
--- a/drivers/usb/host/pci-quirks.h
+++ b/drivers/usb/host/pci-quirks.h
@@ -15,6 +15,7 @@ void usb_asmedia_modifyflowcontrol(struct pci_dev *pdev);
void usb_enable_intel_xhci_ports(struct pci_dev *xhci_pdev);
void usb_disable_xhci_ports(struct pci_dev *xhci_pdev);
void sb800_prefetch(struct device *dev, int on);
+bool usb_xhci_needs_pci_reset(struct pci_dev *pdev);
#else
struct pci_dev;
static inline void usb_amd_quirk_pll_disable(void) {}
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 5b0fa553c8bc..8071c8fdd15e 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -284,6 +284,13 @@ static int xhci_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
driver = (struct hc_driver *)id->driver_data;
+ /* For some HW implementation, a XHCI reset is just not enough... */
+ if (usb_xhci_needs_pci_reset(dev)) {
+ dev_info(&dev->dev, "Resetting\n");
+ if (pci_reset_function_locked(dev))
+ dev_warn(&dev->dev, "Reset failed");
+ }
+
/* Prevent runtime suspending between USB-2 and USB-3 initialization */
pm_runtime_get_noresume(&dev->dev);