Merge branch 'pci/bwctrl'

- Disable bwctrl on Intel P45 to avoid a boot hang (Ilpo Järvinen)

* pci/bwctrl:
  PCI/bwctrl: Disable BW controller on Intel P45 using a quirk

drivers/pci/pcie/bwctrl.c

@@ -250,6 +250,9 @@ static int pcie_bwnotif_probe(struct pcie_device *srv)
 	struct pci_dev *port = srv->port;
 	int ret;
 
+	if (port->no_bw_notif)
+		return -ENODEV;
+
 	/* Can happen if we run out of bus numbers during enumeration. */
 	if (!port->subordinate)
 		return -ENODEV;

drivers/pci/quirks.c

@@ -1359,6 +1359,16 @@ static void quirk_transparent_bridge(struct pci_dev *dev)
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL,	PCI_DEVICE_ID_INTEL_82380FB,	quirk_transparent_bridge);
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_TOSHIBA,	0x605,	quirk_transparent_bridge);
 
+/*
+ * Enabling Link Bandwidth Management Interrupts (BW notifications) can cause
+ * boot hangs on P45.
+ */
+static void quirk_p45_bw_notifications(struct pci_dev *dev)
+{
+	dev->no_bw_notif = 1;
+}
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2e21, quirk_p45_bw_notifications);
+
 /*
  * Common misconfiguration of the MediaGX/Geode PCI master that will reduce
  * PCI bandwidth from 70MB/s to 25MB/s.  See the GXM/GXLV/GX1 datasheets

include/linux/pci.h

@@ -406,6 +406,7 @@ struct pci_dev {
 						      user sysfs */
 	unsigned int	clear_retrain_link:1;	/* Need to clear Retrain Link
 						   bit manually */
+	unsigned int	no_bw_notif:1;	/* BW notifications may cause issues */
 	unsigned int	d3hot_delay;	/* D3hot->D0 transition time in ms */
 	unsigned int	d3cold_delay;	/* D3cold->D0 transition time in ms */