diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c index b2cde04ede1a..6eba9b2cfb90 100644 --- a/drivers/pci/hotplug/pciehp_hpc.c +++ b/drivers/pci/hotplug/pciehp_hpc.c @@ -636,15 +636,57 @@ static int hpc_power_on_slot(struct slot * slot) return retval; } +static inline int pcie_mask_bad_dllp(struct controller *ctrl) +{ + struct pci_dev *dev = ctrl->pci_dev; + int pos; + u32 reg; + + pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR); + if (!pos) + return 0; + pci_read_config_dword(dev, pos + PCI_ERR_COR_MASK, ®); + if (reg & PCI_ERR_COR_BAD_DLLP) + return 0; + reg |= PCI_ERR_COR_BAD_DLLP; + pci_write_config_dword(dev, pos + PCI_ERR_COR_MASK, reg); + return 1; +} + +static inline void pcie_unmask_bad_dllp(struct controller *ctrl) +{ + struct pci_dev *dev = ctrl->pci_dev; + u32 reg; + int pos; + + pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR); + if (!pos) + return; + pci_read_config_dword(dev, pos + PCI_ERR_COR_MASK, ®); + if (!(reg & PCI_ERR_COR_BAD_DLLP)) + return; + reg &= ~PCI_ERR_COR_BAD_DLLP; + pci_write_config_dword(dev, pos + PCI_ERR_COR_MASK, reg); +} + static int hpc_power_off_slot(struct slot * slot) { struct controller *ctrl = slot->ctrl; u16 slot_cmd; u16 cmd_mask; int retval = 0; + int changed; dbg("%s: slot->hp_slot %x\n", __FUNCTION__, slot->hp_slot); + /* + * Set Bad DLLP Mask bit in Correctable Error Mask + * Register. This is the workaround against Bad DLLP error + * that sometimes happens during turning power off the slot + * which conforms to PCI Express 1.0a spec. + */ + changed = pcie_mask_bad_dllp(ctrl); + slot_cmd = POWER_OFF; cmd_mask = PWR_CTRL; /* @@ -681,6 +723,9 @@ static int hpc_power_off_slot(struct slot * slot) */ msleep(1000); + if (changed) + pcie_unmask_bad_dllp(ctrl); + return retval; }