diff options
Diffstat (limited to 'drivers/pci/pci.c')
| -rw-r--r-- | drivers/pci/pci.c | 94 |
1 files changed, 83 insertions, 11 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index ee7c2f4eef9b..b309ce855577 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -35,6 +35,8 @@ #include <linux/aer.h> #include "pci.h" +DEFINE_MUTEX(pci_slot_mutex); + const char *pci_power_names[] = { "error", "D0", "D1", "D2", "D3hot", "D3cold", "unknown", }; @@ -791,6 +793,11 @@ static inline bool platform_pci_need_resume(struct pci_dev *dev) return pci_platform_pm ? pci_platform_pm->need_resume(dev) : false; } +static inline bool platform_pci_bridge_d3(struct pci_dev *dev) +{ + return pci_platform_pm ? pci_platform_pm->bridge_d3(dev) : false; +} + /** * pci_raw_set_power_state - Use PCI PM registers to set the power state of * given PCI device @@ -1284,6 +1291,7 @@ int pci_save_state(struct pci_dev *dev) if (i != 0) return i; + pci_save_dpc_state(dev); return pci_save_vc_state(dev); } EXPORT_SYMBOL(pci_save_state); @@ -1378,6 +1386,7 @@ void pci_restore_state(struct pci_dev *dev) pci_restore_ats_state(dev); pci_restore_vc_state(dev); pci_restore_rebar_state(dev); + pci_restore_dpc_state(dev); pci_cleanup_aer_error_status_regs(dev); @@ -2133,10 +2142,13 @@ static int __pci_enable_wake(struct pci_dev *dev, pci_power_t state, bool enable int ret = 0; /* - * Bridges can only signal wakeup on behalf of subordinate devices, - * but that is set up elsewhere, so skip them. + * Bridges that are not power-manageable directly only signal + * wakeup on behalf of subordinate devices which is set up + * elsewhere, so skip them. However, bridges that are + * power-manageable may signal wakeup for themselves (for example, + * on a hotplug event) and they need to be covered here. */ - if (pci_has_subordinate(dev)) + if (!pci_power_manageable(dev)) return 0; /* Don't do the same thing twice in a row for one device. */ @@ -2511,6 +2523,10 @@ bool pci_bridge_d3_possible(struct pci_dev *bridge) if (bridge->is_thunderbolt) return true; + /* Platform might know better if the bridge supports D3 */ + if (platform_pci_bridge_d3(bridge)) + return true; + /* * Hotplug ports handled natively by the OS were not validated * by vendors for runtime D3 at least until 2018 because there @@ -4496,21 +4512,42 @@ bool pcie_wait_for_link(struct pci_dev *pdev, bool active) bool ret; u16 lnk_status; + /* + * Some controllers might not implement link active reporting. In this + * case, we wait for 1000 + 100 ms. + */ + if (!pdev->link_active_reporting) { + msleep(1100); + return true; + } + + /* + * PCIe r4.0 sec 6.6.1, a component must enter LTSSM Detect within 20ms, + * after which we should expect an link active if the reset was + * successful. If so, software must wait a minimum 100ms before sending + * configuration requests to devices downstream this port. + * + * If the link fails to activate, either the device was physically + * removed or the link is permanently failed. + */ + if (active) + msleep(20); for (;;) { pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status); ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA); if (ret == active) - return true; + break; if (timeout <= 0) break; msleep(10); timeout -= 10; } - - pci_info(pdev, "Data Link Layer Link Active not %s in 1000 msec\n", - active ? "set" : "cleared"); - - return false; + if (active && ret) + msleep(100); + else if (ret != active) + pci_info(pdev, "Data Link Layer Link Active not %s in 1000 msec\n", + active ? "set" : "cleared"); + return ret == active; } void pci_reset_secondary_bus(struct pci_dev *dev) @@ -4582,13 +4619,13 @@ static int pci_reset_hotplug_slot(struct hotplug_slot *hotplug, int probe) { int rc = -ENOTTY; - if (!hotplug || !try_module_get(hotplug->ops->owner)) + if (!hotplug || !try_module_get(hotplug->owner)) return rc; if (hotplug->ops->reset_slot) rc = hotplug->ops->reset_slot(hotplug, probe); - module_put(hotplug->ops->owner); + module_put(hotplug->owner); return rc; } @@ -5165,6 +5202,41 @@ static int pci_bus_reset(struct pci_bus *bus, int probe) } /** + * pci_bus_error_reset - reset the bridge's subordinate bus + * @bridge: The parent device that connects to the bus to reset + * + * This function will first try to reset the slots on this bus if the method is + * available. If slot reset fails or is not available, this will fall back to a + * secondary bus reset. + */ +int pci_bus_error_reset(struct pci_dev *bridge) +{ + struct pci_bus *bus = bridge->subordinate; + struct pci_slot *slot; + + if (!bus) + return -ENOTTY; + + mutex_lock(&pci_slot_mutex); + if (list_empty(&bus->slots)) + goto bus_reset; + + list_for_each_entry(slot, &bus->slots, list) + if (pci_probe_reset_slot(slot)) + goto bus_reset; + + list_for_each_entry(slot, &bus->slots, list) + if (pci_slot_reset(slot, 0)) + goto bus_reset; + + mutex_unlock(&pci_slot_mutex); + return 0; +bus_reset: + mutex_unlock(&pci_slot_mutex); + return pci_bus_reset(bridge->subordinate, 0); +} + +/** * pci_probe_reset_bus - probe whether a PCI bus can be reset * @bus: PCI bus to probe * |