e1000e: Add code to check for failure of pci_disable_link_state call
This patch attempts to work around a problem found with some systems where
the call to pci_diable_link_state_locked() fails. As a result, ASPM is not,
in fact, disabled. Changing disable ASPM code to check if state actually
is disabled after the call and, if not, try another way to disable it.
Signed-off-by: Carolyn Wyborny <carolyn.wyborny@intel.com>
Acked-by: Bruce W. Allan <bruce.w.allan@intel.com>
Tested-by: Pavel Machek <pavel@ucw.cz>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
index e6d2c0f..59c0c54 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -64,8 +64,6 @@
module_param(debug, int, 0);
MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
-static void e1000e_disable_aspm(struct pci_dev *pdev, u16 state);
-
static const struct e1000_info *e1000_info_tbl[] = {
[board_82571] = &e1000_82571_info,
[board_82572] = &e1000_82572_info,
@@ -6019,38 +6017,73 @@
return 0;
}
-#ifdef CONFIG_PCIEASPM
-static void __e1000e_disable_aspm(struct pci_dev *pdev, u16 state)
+/**
+ * e1000e_disable_aspm - Disable ASPM states
+ * @pdev: pointer to PCI device struct
+ * @state: bit-mask of ASPM states to disable
+ *
+ * Some devices *must* have certain ASPM states disabled per hardware errata.
+ **/
+static void e1000e_disable_aspm(struct pci_dev *pdev, u16 state)
{
- pci_disable_link_state_locked(pdev, state);
-}
-#else
-static void __e1000e_disable_aspm(struct pci_dev *pdev, u16 state)
-{
- u16 aspm_ctl = 0;
+ struct pci_dev *parent = pdev->bus->self;
+ u16 aspm_dis_mask = 0;
+ u16 pdev_aspmc, parent_aspmc;
- if (state & PCIE_LINK_STATE_L0S)
- aspm_ctl |= PCI_EXP_LNKCTL_ASPM_L0S;
- if (state & PCIE_LINK_STATE_L1)
- aspm_ctl |= PCI_EXP_LNKCTL_ASPM_L1;
+ switch (state) {
+ case PCIE_LINK_STATE_L0S:
+ case PCIE_LINK_STATE_L0S | PCIE_LINK_STATE_L1:
+ aspm_dis_mask |= PCI_EXP_LNKCTL_ASPM_L0S;
+ /* fall-through - can't have L1 without L0s */
+ case PCIE_LINK_STATE_L1:
+ aspm_dis_mask |= PCI_EXP_LNKCTL_ASPM_L1;
+ break;
+ default:
+ return;
+ }
+
+ pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &pdev_aspmc);
+ pdev_aspmc &= PCI_EXP_LNKCTL_ASPMC;
+
+ if (parent) {
+ pcie_capability_read_word(parent, PCI_EXP_LNKCTL,
+ &parent_aspmc);
+ parent_aspmc &= PCI_EXP_LNKCTL_ASPMC;
+ }
+
+ /* Nothing to do if the ASPM states to be disabled already are */
+ if (!(pdev_aspmc & aspm_dis_mask) &&
+ (!parent || !(parent_aspmc & aspm_dis_mask)))
+ return;
+
+ dev_info(&pdev->dev, "Disabling ASPM %s %s\n",
+ (aspm_dis_mask & pdev_aspmc & PCI_EXP_LNKCTL_ASPM_L0S) ?
+ "L0s" : "",
+ (aspm_dis_mask & pdev_aspmc & PCI_EXP_LNKCTL_ASPM_L1) ?
+ "L1" : "");
+
+#ifdef CONFIG_PCIEASPM
+ pci_disable_link_state_locked(pdev, state);
+
+ /* Double-check ASPM control. If not disabled by the above, the
+ * BIOS is preventing that from happening (or CONFIG_PCIEASPM is
+ * not enabled); override by writing PCI config space directly.
+ */
+ pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &pdev_aspmc);
+ pdev_aspmc &= PCI_EXP_LNKCTL_ASPMC;
+
+ if (!(aspm_dis_mask & pdev_aspmc))
+ return;
+#endif
/* Both device and parent should have the same ASPM setting.
* Disable ASPM in downstream component first and then upstream.
*/
- pcie_capability_clear_word(pdev, PCI_EXP_LNKCTL, aspm_ctl);
+ pcie_capability_clear_word(pdev, PCI_EXP_LNKCTL, aspm_dis_mask);
- if (pdev->bus->self)
- pcie_capability_clear_word(pdev->bus->self, PCI_EXP_LNKCTL,
- aspm_ctl);
-}
-#endif
-static void e1000e_disable_aspm(struct pci_dev *pdev, u16 state)
-{
- dev_info(&pdev->dev, "Disabling ASPM %s %s\n",
- (state & PCIE_LINK_STATE_L0S) ? "L0s" : "",
- (state & PCIE_LINK_STATE_L1) ? "L1" : "");
-
- __e1000e_disable_aspm(pdev, state);
+ if (parent)
+ pcie_capability_clear_word(parent, PCI_EXP_LNKCTL,
+ aspm_dis_mask);
}
#ifdef CONFIG_PM