1 files changed, 26 insertions, 3 deletions

diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 8f63f4c6b85f..9aad608bcf3f 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -16,6 +16,7 @@
 #include <linux/pm.h>
 #include <linux/init.h>
 #include <linux/slab.h>
+#include <linux/jiffies.h>
 #include <linux/pci-aspm.h>
 #include "../pci.h"
 
@@ -161,11 +162,12 @@ static void pcie_check_clock_pm(struct pci_dev *pdev)
  */
 static void pcie_aspm_configure_common_clock(struct pci_dev *pdev)
 {
-        int pos, child_pos;
+        int pos, child_pos, i = 0;
         u16 reg16 = 0;
         struct pci_dev *child_dev;
         int same_clock = 1;
-
+        unsigned long start_jiffies;
+        u16 child_regs[8], parent_reg;
         /*
          * all functions of a slot should have the same Slot Clock
          * Configuration, so just check one function
@@ -191,16 +193,19 @@ static void pcie_aspm_configure_common_clock(struct pci_dev *pdev)
                 child_pos = pci_find_capability(child_dev, PCI_CAP_ID_EXP);
                 pci_read_config_word(child_dev, child_pos + PCI_EXP_LNKCTL,
                         &reg16);
+                child_regs[i] = reg16;
                 if (same_clock)
                         reg16 |= PCI_EXP_LNKCTL_CCC;
                 else
                         reg16 &= ~PCI_EXP_LNKCTL_CCC;
                 pci_write_config_word(child_dev, child_pos + PCI_EXP_LNKCTL,
                         reg16);
+                i++;
         }
 
         /* Configure upstream component */
         pci_read_config_word(pdev, pos + PCI_EXP_LNKCTL, &reg16);
+        parent_reg = reg16;
         if (same_clock)
                 reg16 |= PCI_EXP_LNKCTL_CCC;
         else
@@ -212,12 +217,30 @@ static void pcie_aspm_configure_common_clock(struct pci_dev *pdev)
         pci_write_config_word(pdev, pos + PCI_EXP_LNKCTL, reg16);
 
         /* Wait for link training end */
-        while (1) {
+        /* break out after waiting for 1 second */
+        start_jiffies = jiffies;
+        while ((jiffies - start_jiffies) < HZ) {
                 pci_read_config_word(pdev, pos + PCI_EXP_LNKSTA, &reg16);
                 if (!(reg16 & PCI_EXP_LNKSTA_LT))
                         break;
                 cpu_relax();
         }
+        /* training failed -> recover */
+        if ((jiffies - start_jiffies) >= HZ) {
+                dev_printk (KERN_ERR, &pdev->dev, "ASPM: Could not configure"
+                            " common clock\n");
+                i = 0;
+                list_for_each_entry(child_dev, &pdev->subordinate->devices,
+                                    bus_list) {
+                        child_pos = pci_find_capability(child_dev,
+                                                        PCI_CAP_ID_EXP);
+                        pci_write_config_word(child_dev,
+                                              child_pos + PCI_EXP_LNKCTL,
+                                              child_regs[i]);
+                        i++;
+                }
+                pci_write_config_word(pdev, pos + PCI_EXP_LNKCTL, parent_reg);
+        }
 }
 
 /*