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path: root/drivers/pci/pcie/aspm.c
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Diffstat (limited to 'drivers/pci/pcie/aspm.c')
-rw-r--r--drivers/pci/pcie/aspm.c29
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);
+ }
}
/*
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