From 13129d9b6183bf93b005ed9ad0eb46122794fe21 Mon Sep 17 00:00:00 2001 From: Carolyn Wyborny Date: Sat, 3 Aug 2013 01:53:54 +0000 Subject: [PATCH] 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 Acked-by: Bruce W. Allan Tested-by: Pavel Machek Tested-by: Aaron Brown Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/e1000e/netdev.c | 87 +++++++++++++++------- 1 file changed, 60 insertions(+), 27 deletions(-) diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c index e6d2c0f8f76a..59c0c5413797 100644 --- a/drivers/net/ethernet/intel/e1000e/netdev.c +++ b/drivers/net/ethernet/intel/e1000e/netdev.c @@ -64,8 +64,6 @@ static int debug = -1; 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 @@ static int __e1000_shutdown(struct pci_dev *pdev, bool runtime) 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