Merge branches 'pci/aer', 'pci/enumeration', 'pci/kconfig', 'pci/misc', 'pci/virtuali...

[linux-2.6-block.git] / drivers / pci / pci.c

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 0a9c8db51c08f8f7bbb6a1fda9240e063535767d..eaf4ffc0c27363bcde85fc4141f882fede59fcde 100644 (file)
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3401,6 +3401,29 @@ int pci_wait_for_pending_transaction(struct pci_dev *dev)
 }
 EXPORT_SYMBOL(pci_wait_for_pending_transaction);
 
+/*
+ * We should only need to wait 100ms after FLR, but some devices take longer.
+ * Wait for up to 1000ms for config space to return something other than -1.
+ * Intel IGD requires this when an LCD panel is attached.  We read the 2nd
+ * dword because VFs don't implement the 1st dword.
+ */
+static void pci_flr_wait(struct pci_dev *dev)
+{
+       int i = 0;
+       u32 id;
+
+       do {
+               msleep(100);
+               pci_read_config_dword(dev, PCI_COMMAND, &id);
+       } while (i++ < 10 && id == ~0);
+
+       if (id == ~0)
+               dev_warn(&dev->dev, "Failed to return from FLR\n");
+       else if (i > 1)
+               dev_info(&dev->dev, "Required additional %dms to return from FLR\n",
+                        (i - 1) * 100);
+}
+
 static int pcie_flr(struct pci_dev *dev, int probe)
 {
        u32 cap;
@@ -3416,7 +3439,7 @@ static int pcie_flr(struct pci_dev *dev, int probe)
                dev_err(&dev->dev, "timed out waiting for pending transaction; performing function level reset anyway\n");
 
        pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_BCR_FLR);
-       msleep(100);
+       pci_flr_wait(dev);
        return 0;
 }
 
@@ -3446,7 +3469,7 @@ static int pci_af_flr(struct pci_dev *dev, int probe)
                dev_err(&dev->dev, "timed out waiting for pending transaction; performing AF function level reset anyway\n");
 
        pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR);
-       msleep(100);
+       pci_flr_wait(dev);
        return 0;
 }