summaryrefslogtreecommitdiffstats
path: root/drivers/pci/pci.c
diff options
context:
space:
mode:
authorBjorn Helgaas <bhelgaas@google.com>2018-10-20 11:45:29 -0500
committerBjorn Helgaas <bhelgaas@google.com>2018-10-20 11:45:29 -0500
commit20634dc361e1c5fe2dae380a7d0a21ca7f32c4f7 (patch)
tree51666a1885b3b682120553219265722db5eddac4 /drivers/pci/pci.c
parentde468b755464426c276df2daf1e54bcd64186020 (diff)
parente51cd9ce5dd3b10f9e67a30a4dc00fc1fa80c673 (diff)
downloadlinux-20634dc361e1c5fe2dae380a7d0a21ca7f32c4f7.tar.bz2
Merge branch 'pci/hotplug'
- Differentiate between pciehp surprise and safe removal (Lukas Wunner) - Remove unnecessary pciehp includes (Lukas Wunner) - Drop pciehp hotplug_slot_ops wrappers (Lukas Wunner) - Tolerate PCIe Slot Presence Detect being hardwired to zero to workaround broken hardware, e.g., the Wilocity switch/wireless device (Lukas Wunner) - Unify pciehp controller & slot structs (Lukas Wunner) - Constify hotplug_slot_ops (Lukas Wunner) - Drop hotplug_slot_info (Lukas Wunner) - Embed hotplug_slot struct into users instead of allocating it separately (Lukas Wunner) - Initialize PCIe port service drivers directly instead of relying on initcall ordering (Keith Busch) - Restore PCI config state after a slot reset (Keith Busch) - Save/restore DPC config state along with other PCI config state (Keith Busch) - Reference count devices during AER handling to avoid race issue with concurrent hot removal (Keith Busch) - If an Upstream Port reports ERR_FATAL, don't try to read the Port's config space because it is probably unreachable (Keith Busch) - During error handling, use slot-specific reset instead of secondary bus reset to avoid link up/down issues on hotplug ports (Keith Busch) - Restore previous AER/DPC handling that does not remove and re-enumerate devices on ERR_FATAL (Keith Busch) - Notify all drivers that may be affected by error recovery resets (Keith Busch) - Always generate error recovery uevents, even if a driver doesn't have error callbacks (Keith Busch) - Make PCIe link active reporting detection generic (Keith Busch) - Support D3cold in PCIe hierarchies during system sleep and runtime, including hotplug and Thunderbolt ports (Mika Westerberg) - Handle hpmemsize/hpiosize kernel parameters uniformly, whether slots are empty or occupied (Jon Derrick) - Remove duplicated include from pci/pcie/err.c and unused variable from cpqphp (YueHaibing) - Remove driver pci_cleanup_aer_uncorrect_error_status() calls (Oza Pawandeep) - Uninline PCI bus accessors for better ftracing (Keith Busch) - Remove unused AER Root Port .error_resume method (Keith Busch) - Use kfifo in AER instead of a local version (Keith Busch) - Use threaded IRQ in AER bottom half (Keith Busch) - Use managed resources in AER core (Keith Busch) - Reuse pcie_port_find_device() for AER injection (Keith Busch) - Abstract AER interrupt handling to disconnect error injection (Keith Busch) - Refactor AER injection callbacks to simplify future improvments (Keith Busch) * pci/hotplug: PCI/AER: Refactor error injection fallbacks PCI/AER: Abstract AER interrupt handling PCI/AER: Reuse existing pcie_port_find_device() interface PCI/AER: Use managed resource allocations PCI/AER: Use threaded IRQ for bottom half PCI/AER: Use kfifo_in_spinlocked() to insert locked elements PCI/AER: Use kfifo for tracking events instead of reimplementing it PCI/AER: Remove error source from AER struct aer_rpc PCI/AER: Remove unused aer_error_resume() PCI: Uninline PCI bus accessors for better ftracing PCI/AER: Remove pci_cleanup_aer_uncorrect_error_status() calls PCI: pnv_php: Use kmemdup() PCI: cpqphp: Remove set but not used variable 'physical_slot' PCI/ERR: Remove duplicated include from err.c PCI: Equalize hotplug memory and io for occupied and empty slots PCI / ACPI: Whitelist D3 for more PCIe hotplug ports ACPI / property: Allow multiple property compatible _DSD entries PCI/PME: Implement runtime PM callbacks PCI: pciehp: Implement runtime PM callbacks PCI/portdrv: Add runtime PM hooks for port service drivers PCI/portdrv: Resume upon exit from system suspend if left runtime suspended PCI: pciehp: Do not handle events if interrupts are masked PCI: pciehp: Disable hotplug interrupt during suspend PCI / ACPI: Enable wake automatically for power managed bridges PCI: Do not skip power-managed bridges in pci_enable_wake() PCI: Make link active reporting detection generic PCI: Unify device inaccessible PCI/ERR: Always report current recovery status for udev PCI/ERR: Simplify broadcast callouts PCI/ERR: Run error recovery callbacks for all affected devices PCI/ERR: Handle fatal error recovery PCI/ERR: Use slot reset if available PCI/AER: Don't read upstream ports below fatal errors PCI/AER: Take reference on error devices PCI/DPC: Save and restore config state PCI: portdrv: Restore PCI config state on slot reset PCI: portdrv: Initialize service drivers directly PCI: hotplug: Document TODOs PCI: hotplug: Embed hotplug_slot PCI: hotplug: Drop hotplug_slot_info PCI: hotplug: Constify hotplug_slot_ops PCI: pciehp: Reshuffle controller struct for clarity PCI: pciehp: Rename controller struct members for clarity PCI: pciehp: Unify controller and slot structs PCI: pciehp: Tolerate Presence Detect hardwired to zero PCI: pciehp: Drop hotplug_slot_ops wrappers PCI: pciehp: Drop unnecessary includes PCI: pciehp: Differentiate between surprise and safe removal PCI: Simplify disconnected marking
Diffstat (limited to 'drivers/pci/pci.c')
-rw-r--r--drivers/pci/pci.c94
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
*