diff options
| author | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2020-06-22 14:35:23 +0300 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2020-07-22 23:41:03 +0300 |
| commit | 068c29a248b6ddbfdf7bb150b547569759620d36 (patch) | |
| tree | 1533d2db55c0a1371985e1746d8fdb6acadedba9 /drivers/pci/pcie/err.c | |
| parent | 600a5b4fc8e8f6dad098cd50e0e727cb2a16be46 (diff) | |
| download | linux-068c29a248b6ddbfdf7bb150b547569759620d36.tar.xz | |
PCI/ERR: Clear PCIe Device Status errors only if OS owns AER
pcie_clear_device_status() resets the error bits in the PCIe Device Status
Register (PCI_EXP_DEVSTA).
Previously we did this unconditionally, but on ACPI systems, the _OSC AER
bit negotiates control of the AER capability. Per sec 4.5.1 of the System
Firmware Intermediary _OSC and DPC Updates ECN [1], this bit also covers
other error enable/status bits including the following:
Correctable Error Reporting Enable
Non-Fatal Error Reporting Enable
Fatal Error Reporting Enable
Unsupported Request Reporting Enable
These bits are all in the PCIe Device Control register (the ECN omitted
"Reporting", but I think that's a typo), so by implication the _OSC AER bit
also applies to the error status bits in the PCIe Device Status register:
Correctable Error Detected
Non-Fatal Error Detected
Fatal Error Detected
Unsupported Request Detected
Clear the PCIe Device Status error bits only when the OS controls the AER
capability and related error enable/status bits. If platform firmware
controls the AER capability, firmware is responsible for clearing these
bits.
One call path leading here is:
ghes_do_proc
ghes_handle_aer
aer_recover_queue
schedule_work(&aer_recover_work)
...
aer_recover_work_func
pcie_do_recovery
pcie_clear_device_status
[1] System Firmware Intermediary (SFI) _OSC and DPC Updates ECN, Feb 24,
2020, affecting PCI Firmware Specification, Rev. 3.2
https://members.pcisig.com/wg/PCI-SIG/document/14076
[bhelgaas: commit log, move test from pcie_clear_device_status() to callers]
Link: https://lore.kernel.org/r/20200622113523.891666-1-Jonathan.Cameron@huawei.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Diffstat (limited to 'drivers/pci/pcie/err.c')
| -rw-r--r-- | drivers/pci/pcie/err.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c index 55755bc493f1..c543f419d8f9 100644 --- a/drivers/pci/pcie/err.c +++ b/drivers/pci/pcie/err.c @@ -197,7 +197,8 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, pci_dbg(dev, "broadcast resume message\n"); pci_walk_bus(bus, report_resume, &status); - pcie_clear_device_status(dev); + if (pcie_aer_is_native(dev)) + pcie_clear_device_status(dev); pci_aer_clear_nonfatal_status(dev); pci_info(dev, "device recovery successful\n"); return status; |