diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index 8dfb6c602ff8..6b4e82a4b64e 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -220,6 +220,15 @@ static bool pcie_retrain_link(struct pcie_link_state *link) pcie_capability_read_word(parent, PCI_EXP_LNKCTL, ®16); reg16 |= PCI_EXP_LNKCTL_RL; pcie_capability_write_word(parent, PCI_EXP_LNKCTL, reg16); + if (parent->clear_retrain_link) { + /* + * Due to an erratum in some devices the Retrain Link bit + * needs to be cleared again manually to allow the link + * training to succeed. + */ + reg16 &= ~PCI_EXP_LNKCTL_RL; + pcie_capability_write_word(parent, PCI_EXP_LNKCTL, reg16); + } /* Wait for link training end. Break out after waiting for timeout */ start_jiffies = jiffies; diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 541efca8db0b..45c3fbd38f50 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -2085,6 +2085,23 @@ DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x10f1, quirk_disable_aspm_l0s); DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x10f4, quirk_disable_aspm_l0s); DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x1508, quirk_disable_aspm_l0s); +/* + * Some Pericom PCIe-to-PCI bridges in reverse mode need the PCIe Retrain + * Link bit cleared after starting the link retrain process to allow this + * process to finish. + * + * Affected devices: PI7C9X110, PI7C9X111SL, PI7C9X130. See also the + * Pericom Errata Sheet PI7C9X111SLB_errata_rev1.2_102711.pdf. + */ +static void quirk_enable_clear_retrain_link(struct pci_dev *dev) +{ + dev->clear_retrain_link = 1; + pci_info(dev, "Enable PCIe Retrain Link quirk\n"); +} +DECLARE_PCI_FIXUP_HEADER(0x12d8, 0xe110, quirk_enable_clear_retrain_link); +DECLARE_PCI_FIXUP_HEADER(0x12d8, 0xe111, quirk_enable_clear_retrain_link); +DECLARE_PCI_FIXUP_HEADER(0x12d8, 0xe130, quirk_enable_clear_retrain_link); + static void fixup_rev1_53c810(struct pci_dev *dev) { u32 class = dev->class; diff --git a/include/linux/pci.h b/include/linux/pci.h index b1abbcc614cf..59f4d10568c6 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -350,6 +350,8 @@ struct pci_dev { unsigned int hotplug_user_indicators:1; /* SlotCtl indicators controlled exclusively by user sysfs */ + unsigned int clear_retrain_link:1; /* Need to clear Retrain Link + bit manually */ unsigned int d3_delay; /* D3->D0 transition time in ms */ unsigned int d3cold_delay; /* D3cold->D0 transition time in ms */