- Save/restore Precision Time Measurement Capability for suspend/resume
(David E. Box)
- Disable PTM during suspend to save power (David E. Box)
* pci/ptm:
PCI: Disable PTM during suspend to save power
PCI/PTM: Save/restore Precision Time Measurement Capability for suspend/resume
- Stop writing AER Capability when we don't own it (Sean V Kelley)
- Bind RCEC devices to the Port driver (Qiuxu Zhuo)
- Cache the RCEC RA Capability offset (Sean V Kelley)
- Add pci_walk_bridge() (Sean V Kelley)
- Clear AER status only when we control AER (Sean V Kelley)
- Recover from RCEC AER errors (Sean V Kelley)
- Add pcie_link_rcec() to associate RCiEPs with RCECs (Sean V Kelley)
- Recover from RCiEP AER errors (Sean V Kelley)
- Add pcie_walk_rcec() for RCEC AER handling (Sean V Kelley)
- Add pcie_walk_rcec() for RCEC PME handling (Sean V Kelley)
- Add RCEC AER error injection support (Qiuxu Zhuo)
* pci/err:
PCI/AER: Add RCEC AER error injection support
PCI/PME: Add pcie_walk_rcec() to RCEC PME handling
PCI/AER: Add pcie_walk_rcec() to RCEC AER handling
PCI/ERR: Recover from RCiEP AER errors
PCI/ERR: Add pcie_link_rcec() to associate RCiEPs
PCI/ERR: Recover from RCEC AER errors
PCI/ERR: Clear AER status only when we control AER
PCI/ERR: Add pci_walk_bridge() to pcie_do_recovery()
PCI/ERR: Avoid negated conditional for clarity
PCI/ERR: Use "bridge" for clarity in pcie_do_recovery()
PCI/ERR: Simplify by computing pci_pcie_type() once
PCI/ERR: Simplify by using pci_upstream_bridge()
PCI/ERR: Rename reset_link() to reset_subordinates()
PCI/ERR: Cache RCEC EA Capability offset in pci_init_capabilities()
PCI/ERR: Bind RCEC devices to the Root Port driver
PCI/AER: Write AER Capability only when we control it
There are systems (for example, Intel based mobile platforms since Coffee
Lake) where the power drawn while suspended can be significantly reduced by
disabling Precision Time Measurement (PTM) on PCIe root ports as this
allows the port to enter a lower-power PM state and the SoC to reach a
lower-power idle state. To save this power, disable the PTM feature on root
ports during pci_prepare_to_sleep() and pci_finish_runtime_suspend(). The
feature will be returned to its previous state during restore and error
recovery.
Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=209361
Link: https://lore.kernel.org/r/20201207223951.19667-2-david.e.box@linux.intel.com
Reported-by: Len Brown <len.brown@intel.com>
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The PCI subsystem does not currently save and restore the configuration
space for the Precision Time Measurement (PTM) Extended Capability leading
to the possibility of the feature returning disabled on S3 resume. This
has been observed on Intel Coffee Lake desktops. Add save/restore of the
PTM control register. This saves the PTM Enable, Root Select, and Effective
Granularity bits.
Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20201207223951.19667-1-david.e.box@linux.intel.com
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Root Complex Event Collectors (RCEC) appear as peers to Root Ports and may
also have the AER capability.
Add RCEC support to the AER error injection driver.
Co-developed-by: Sean V Kelley <sean.v.kelley@intel.com>
Link: https://lore.kernel.org/r/20201121001036.8560-16-sean.v.kelley@intel.com
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # non-native/no RCEC
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Root Complex Event Collectors (RCEC) appear as peers of Root Ports and also
have the PME capability. As with AER, there is a need to be able to walk
the RCiEPs associated with their RCEC for purposes of acting upon them with
callbacks.
Add RCEC support through the use of pcie_walk_rcec() to the current PME
service driver and attach the PME service driver to the RCEC device.
Co-developed-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Link: https://lore.kernel.org/r/20201121001036.8560-15-sean.v.kelley@intel.com
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # non-native/no RCEC
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Root Complex Event Collectors (RCEC) appear as peers to Root Ports and also
have the AER capability. In addition, actions need to be taken for
associated RCiEPs. In such cases the RCECs will need to be walked in order
to find and act upon their respective RCiEPs.
Extend the existing ability to link the RCECs with a walking function
pcie_walk_rcec(). Add RCEC support to the current AER service driver and
attach the AER service driver to the RCEC device.
Co-developed-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Link: https://lore.kernel.org/r/20201121001036.8560-14-sean.v.kelley@intel.com
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # non-native/no RCEC
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Add support for handling AER errors detected by Root Complex Integrated
Endpoints (RCiEPs). These errors are signaled to software natively via a
Root Complex Event Collector (RCEC) or non-natively via ACPI APEI if the
platform retains control of AER or uses a non-standard RCEC-like device.
When recovering from RCiEP errors, the Root Error Command and Status
registers are in the AER Capability of an associated RCEC (if any), not in
a Root Port. In the non-native case, the platform is responsible for those
registers and we can't touch them.
[bhelgaas: commit log, etc]
Co-developed-by: Sean V Kelley <sean.v.kelley@intel.com>
Link: https://lore.kernel.org/r/20201121001036.8560-13-sean.v.kelley@intel.com
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
A Root Complex Event Collector terminates error and PME messages from
associated RCiEPs.
Use the RCEC Endpoint Association Extended Capability to identify
associated RCiEPs. Link the associated RCiEPs as the RCECs are enumerated.
Co-developed-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Link: https://lore.kernel.org/r/20201121001036.8560-12-sean.v.kelley@intel.com
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # non-native/no RCEC
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
A Root Complex Event Collector (RCEC) collects and signals AER errors that
were detected by Root Complex Integrated Endpoints (RCiEPs), but it may
also signal errors it detects itself. This is analogous to errors detected
and signaled by a Root Port.
Update the AER service driver to claim RCECs in addition to Root Ports.
Add support for handling RCEC-detected AER errors. This does not
include handling RCiEP-detected errors that are signaled by the RCEC.
Note that we expect these errors only from the native AER and APEI paths,
not from DPC or EDR.
[bhelgaas: split from combined RCEC/RCiEP patch, commit log]
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
In some cases a bridge may not exist as the hardware controlling may be
handled only by firmware and so is not visible to the OS. This scenario is
also possible in future use cases involving non-native use of RCECs by
firmware. In this scenario, we expect the platform to retain control of the
bridge and to clear error status itself.
Clear error status only when the OS has native control of AER.
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Consolidate subordinate bus checks with pci_walk_bus() into
pci_walk_bridge() for walking below potentially AER affected bridges.
Link: https://lore.kernel.org/r/20201121001036.8560-10-sean.v.kelley@intel.com
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # non-native/no RCEC
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reverse the sense of the Root Port/Downstream Port conditional for clarity.
No functional change intended.
Link: https://lore.kernel.org/r/20201121001036.8560-9-sean.v.kelley@intel.com
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # non-native/no RCEC
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
pcie_do_recovery() may be called with "dev" being either a bridge (Root
Port or Switch Downstream Port) or an Endpoint. The bulk of the function
deals with the bridge, so if we start with an Endpoint, we reset "dev" to
be the bridge leading to it.
For clarity, replace "dev" in the body of the function with "bridge". No
functional change intended.
Link: https://lore.kernel.org/r/20201121001036.8560-8-sean.v.kelley@intel.com
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # non-native/no RCEC
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Instead of calling pci_pcie_type(dev) twice, call it once and save the
result. No functional change intended.
Link: https://lore.kernel.org/r/20201121001036.8560-7-sean.v.kelley@intel.com
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # non-native/no RCEC
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Use pci_upstream_bridge() in place of dev->bus->self. No functional change
intended.
Link: https://lore.kernel.org/r/20201121001036.8560-6-sean.v.kelley@intel.com
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # non-native/no RCEC
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
reset_link() appears to be misnamed. The point is to reset any devices
below a given bridge, so rename it to reset_subordinates() to make it clear
that we are passing a bridge with the intent to reset the devices below it.
Link: https://lore.kernel.org/r/20201121001036.8560-5-sean.v.kelley@intel.com
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # non-native/no RCEC
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Extend support for Root Complex Event Collectors by decoding and caching
the RCEC Endpoint Association Extended Capabilities when enumerating. Use
that cached information for later error source reporting. See PCIe r5.0,
sec 7.9.10.
Co-developed-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Link: https://lore.kernel.org/r/20201121001036.8560-4-sean.v.kelley@intel.com
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # non-native/no RCEC
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
If a Root Complex Integrated Endpoint (RCiEP) is implemented, it may signal
errors through a Root Complex Event Collector (RCEC). Each RCiEP must be
associated with no more than one RCEC.
For an RCEC (which is technically not a Bridge), error messages "received"
from associated RCiEPs must be enabled for "transmission" in order to cause
a System Error via the Root Control register or (when the Advanced Error
Reporting Capability is present) reporting via the Root Error Command
register and logging in the Root Error Status register and Error Source
Identification register.
Given the commonality with Root Ports and the need to also support AER and
PME services for RCECs, extend the Root Port driver to support RCEC devices
by adding the RCEC Class ID to the driver structure.
Co-developed-by: Sean V Kelley <sean.v.kelley@intel.com>
Link: https://lore.kernel.org/r/20201121001036.8560-3-sean.v.kelley@intel.com
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # non-native/no RCEC
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
If an OS has not been granted AER control via _OSC, it should not make
changes to PCI_ERR_ROOT_COMMAND and PCI_ERR_ROOT_STATUS related registers.
Per section 4.5.1 of the System Firmware Intermediary (SFI) _OSC and DPC
Updates ECN [1], this bit also covers these aspects of the PCI Express
Advanced Error Reporting. Based on the above and earlier discussion [2],
make the following changes:
Add a check for the native case (i.e., AER control via _OSC)
Note that the previous "clear, reset, enable" order suggests that the reset
might cause errors that we should ignore. After this commit, those errors
(if any) will remain logged in the PCI_ERR_ROOT_STATUS register.
[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
[2] https://lore.kernel.org/linux-pci/20201020162820.GA370938@bjorn-Precision-5520/
Link: https://lore.kernel.org/r/20201121001036.8560-2-sean.v.kelley@intel.com
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # non-native/no RCEC
Signed-off-by: Sean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously ASPM L1 Substates control registers (CTL1 and CTL2) weren't
saved and restored during suspend/resume leading to L1 Substates
configuration being lost post-resume.
Save the L1 Substates control registers so that the configuration is
retained post-resume.
Link: https://lore.kernel.org/r/20201024190442.871-1-vidyas@nvidia.com
Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
- Remove unnecessary #includes (Gustavo Pimentel)
- Fix intel_mid_pci.c build error when !CONFIG_ACPI (Randy Dunlap)
- Use scnprintf(), not snprintf(), in sysfs "show" functions (Krzysztof
Wilczyński)
- Simplify pci-pf-stub by using module_pci_driver() (Liu Shixin)
- Print IRQ used by Link Bandwidth Notification (Dongdong Liu)
- Update sysfs mmap-related #ifdef comments (Clint Sbisa)
- Simplify pci_dev_reset_slot_function() (Lukas Wunner)
- Use "NULL" instead of "0" to fix sparse warnings (Gustavo Pimentel)
- Simplify bool comparisons (Krzysztof Wilczyński)
- Drop double zeroing for P2PDMA sg_init_table() (Julia Lawall)
* pci/misc:
PCI: v3-semi: Remove unneeded break
PCI/P2PDMA: Drop double zeroing for sg_init_table()
PCI: Simplify bool comparisons
PCI: endpoint: Use "NULL" instead of "0" as a NULL pointer
PCI: Simplify pci_dev_reset_slot_function()
PCI: Update mmap-related #ifdef comments
PCI/LINK: Print IRQ number used by port
PCI/IOV: Simplify pci-pf-stub with module_pci_driver()
PCI: Use scnprintf(), not snprintf(), in sysfs "show" functions
x86/PCI: Fix intel_mid_pci.c build error when ACPI is not enabled
PCI: Remove unnecessary header includes
- Use for_each_child_of_node() and for_each_node_by_name() instead of
open-coding them (Qinglang Miao)
- Reduce pciehp noisiness on hot removal (Lukas Wunner)
- Remove unused assignment in shpchp (Krzysztof Wilczyński)
* pci/hotplug:
PCI: shpchp: Remove unused 'rc' assignment
PCI: pciehp: Reduce noisiness on hot removal
PCI: rpadlpar: Use for_each_child_of_node() and for_each_node_by_name()
Previously we computed L1.2 parameters in the enumeration path, saved them
in struct pcie_link_state.l1ss, and programmed them into the devices
whenever we enabled or disabled L1.2 on the link. But these parameters are
constant and don't need to be updated when enabling/disabling L1.2.
Compute and program the L1.2 parameters once during enumeration and remove
the struct pcie_link_state.l1ss member. No functional change intended.
[bhelgaas: rework to program L1.2 parameters during enumeration]
Link: https://lore.kernel.org/r/20201015193039.12585-13-helgaas@kernel.org
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously we stored the L1SS Capabilities value in the struct
aspm_register_info.
We only need this information in one place, so read it there and remove
struct aspm_register_info completely, since it's now empty. No functional
change intended.
[bhelgaas: split up, don't cache l1ss_cap in pci_dev]
Link: https://lore.kernel.org/r/20201015193039.12585-12-helgaas@kernel.org
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
aspm_calc_l1ss_info() needs only the L1SS Capabilities. It doesn't need
anything else from struct aspm_register_info, so pass only the Capabilities
value. No functional change intended.
Link: https://lore.kernel.org/r/20201015193039.12585-11-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously we stored the L1SS Control 1 register in the struct
aspm_register_info.
We only need this information in one place, so read it there and remove it
from struct aspm_register_info. No functional change intended.
[bhelgaas: split ctl1/ctl2]
Link: https://lore.kernel.org/r/20201015193039.12585-10-helgaas@kernel.org
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Save the L1 Substates Capability pointer in struct pci_dev. Then we don't
have to keep track of it in the struct aspm_register_info and struct
pcie_link_state, which makes the code easier to read. No functional change
intended.
[bhelgaas: split to a separate patch]
Link: https://lore.kernel.org/r/20201015193039.12585-8-helgaas@kernel.org
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously we stored L0s and L1 Exit Latency information from the Link
Capabilities register in the struct aspm_register_info.
We only need these latencies when we already have the Link Capabilities
values, so use those directly and remove the latencies from struct
aspm_register_info. No functional change intended.
Link: https://lore.kernel.org/r/20201015193039.12585-7-helgaas@kernel.org
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously we stored the "ASPM Control" bits from the Link Control register
in the struct aspm_register_info.
Read PCI_EXP_LNKCTL directly when needed. This means we can use the
PCI_EXP_LNKCTL_ASPM_* bits directly instead of the similar but different
PCIE_LINK_STATE_* bits. No functional change intended.
[bhelgaas: drop get_aspm_enable() and read LNKCTL once directly]
Link: https://lore.kernel.org/r/20201015193039.12585-6-helgaas@kernel.org
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously we stored the "ASPM Support" field from the Link Capabilities
register in the struct aspm_register_info.
Read the Link Capabilities directly when needed and remove it from the
struct aspm_register_info. No functional change intended.
[bhelgaas: remove pci_dev cached copy since LNKCAP isn't truly read-only,
add PCI_EXP_LNKCAP_ASPM_L0S & PCI_EXP_LNKCAP_ASPM_L1, check them directly
instead of adding aspm_support()]
Link: https://lore.kernel.org/r/20201015193039.12585-5-helgaas@kernel.org
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Other users of link->pdev and link->downstream, e.g., pcie_aspm_cap_init(),
pcie_config_aspm_l1ss(), and pcie_config_aspm_link(), use "parent" and
"child" as local names.
Do the same in aspm_calc_l1ss_info() for readability. No functional change
intended.
Link: https://lore.kernel.org/r/20201015193039.12585-4-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
pcie_get_aspm_reg() mostly reads ASPM-related registers, but in some cases
it also updates the value read from PCI_L1SS_CAP based on LTR properties.
Move this update to the point where the value is used to make the code more
readable.
No functional change intended, although previously we could clear
PCI_L1SS_CAP_ASPM_L1_2 for both ends of the link, and now we'll only do it
for the downstream end of a link. This shouldn't matter because we always
test that bit by ANDing l1ss_cap for the upstream and downstream ends.
Link: https://lore.kernel.org/r/20201015193039.12585-3-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
When a PCIe card is hot-removed, the Presence Detect State and Data Link
Layer Link Active bits often do not clear simultaneously. I've seen delays
of up to 244 msec between the two events with Thunderbolt.
After pciehp has brought down the slot in response to the first event, the
other bit may still be set. It's not discernible whether it's set because
a new card is already in the slot or if it will soon clear. So pciehp
tries to bring up the slot and in the latter case fails with a bunch of
messages, some of them at KERN_ERR severity. If the slot is no longer
occupied, the messages are false positives and annoy users.
Stuart Hayes reports the following splat on hot removal:
KERN_INFO pcieport 0000:3c:06.0: pciehp: Slot(180): Link Up
KERN_INFO pcieport 0000:3c:06.0: pciehp: Timeout waiting for Presence Detect
KERN_ERR pcieport 0000:3c:06.0: pciehp: link training error: status 0x0001
KERN_ERR pcieport 0000:3c:06.0: pciehp: Failed to check link status
Dongdong Liu complains about a similar splat:
KERN_INFO pciehp 0000:80:10.0:pcie004: Slot(36): Link Down
KERN_INFO iommu: Removing device 0000:87:00.0 from group 12
KERN_INFO pciehp 0000:80:10.0:pcie004: Slot(36): Card present
KERN_INFO pcieport 0000:80:10.0: Data Link Layer Link Active not set in 1000 msec
KERN_ERR pciehp 0000:80:10.0:pcie004: Failed to check link status
Users are particularly irritated to see a bringup attempt even though the
slot was explicitly brought down via sysfs. In a perfect world, we could
avoid this by setting Link Disable on slot bringdown and re-enabling it
upon a Presence Detect State change. In reality however, there are broken
hotplug ports which hardwire Presence Detect to zero, see 80696f9914
("PCI: pciehp: Tolerate Presence Detect hardwired to zero"). Conversely,
PCIe r1.0 hotplug ports hardwire Link Active to zero because Link Active
Reporting wasn't specified before PCIe r1.1. On unplug, some ports first
clear Presence then Link (see Stuart Hayes' splat) whereas others use the
inverse order (see Dongdong Liu's splat). To top it off, there are hotplug
ports which flap the Presence and Link bits on slot bringup, see
6c35a1ac3d ("PCI: pciehp: Tolerate initially unstable link").
pciehp is designed to work with all of these variants. Surplus attempts at
slot bringup are a lesser evil than not being able to bring up slots at
all. Although we could try to perfect the behavior for specific hotplug
controllers, we'd risk breaking others or increasing code complexity.
But we can certainly minimize annoyance by emitting only a single message
with KERN_INFO severity if bringup is unsuccessful:
* Drop the "Timeout waiting for Presence Detect" message in
pcie_wait_for_presence(). The sole caller of that function,
pciehp_check_link_status(), ignores the timeout and carries on. It emits
error messages of its own and I don't think this particular message adds
much value.
* There's a single error condition in pciehp_check_link_status() which
does not emit a message. Adding one allows dropping the "Failed to check
link status" message emitted by board_added() if
pciehp_check_link_status() returns a non-zero integer.
* Tone down all messages in pciehp_check_link_status() to KERN_INFO
severity and rephrase them to look as innocuous as possible. To this
end, move the message emitted by pcie_wait_for_link_delay() to its
callers.
As a result, Stuart Hayes' splat becomes:
KERN_INFO pcieport 0000:3c:06.0: pciehp: Slot(180): Link Up
KERN_INFO pcieport 0000:3c:06.0: pciehp: Slot(180): Cannot train link: status 0x0001
Dongdong Liu's splat becomes:
KERN_INFO pciehp 0000:80:10.0:pcie004: Slot(36): Card present
KERN_INFO pciehp 0000:80:10.0:pcie004: Slot(36): No link
The messages now merely serve as information that presence or link bits
were set a little longer than expected. Bringup failures which are not
false positives are still reported, albeit no longer at KERN_ERR severity.
Link: https://lore.kernel.org/linux-pci/20200310182100.102987-1-stuart.w.hayes@gmail.com/
Link: https://lore.kernel.org/linux-pci/1547649064-19019-1-git-send-email-liudongdong3@huawei.com/
Link: https://lore.kernel.org/r/b45e46fd8a6aa6930aaac9d7718c2e4b787a4e5e.1595935071.git.lukas@wunner.de
Reported-by: Stuart Hayes <stuart.w.hayes@gmail.com>
Reported-by: Dongdong Liu <liudongdong3@huawei.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Print the IRQ used by PCIe Link Bandwidth Notification services port as
AER, PME and DPC do. It provides convenience to track PCIe BW notification
interrupt counts of certain port from /proc/interrupts.
The dmesg log is as below:
pcieport 0000:00:00.0: bw_notification: enabled with IRQ 1166
Link: https://lore.kernel.org/r/1599737055-73624-1-git-send-email-liudongdong3@huawei.com
Signed-off-by: Dongdong Liu <liudongdong3@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
- Use pci_channel_state_t instead of enum pci_channel_state (Luc Van
Oostenryck)
- Simplify __aer_print_error() (Bjorn Helgaas)
- Log AER correctable errors as warning, not error (Matt Jolly)
- Rename pci_aer_clear_device_status() to pcie_clear_device_status() (Bjorn
Helgaas)
- Clear PCIe Device Status errors only if OS owns AER (Jonathan Cameron)
* pci/error:
PCI/ERR: Clear PCIe Device Status errors only if OS owns AER
PCI/ERR: Rename pci_aer_clear_device_status() to pcie_clear_device_status()
PCI/AER: Log correctable errors as warning, not error
PCI/AER: Simplify __aer_print_error()
PCI: Use 'pci_channel_state_t' instead of 'enum pci_channel_state'
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>
pci_aer_clear_device_status() clears the error bits in the PCIe Device
Status Register (PCI_EXP_DEVSTA). Every PCIe device has this register,
regardless of whether it supports AER.
Rename pci_aer_clear_device_status() to pcie_clear_device_status() to make
clear that it is PCIe-specific but not AER-specific. Move it to
drivers/pci/pci.c, again since it's not AER-specific. No functional change
intended.
Link: https://lore.kernel.org/r/20200717195619.766662-1-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
When I cat ASPM parameter 'policy' by sysfs, it displays as follows. Add a
newline for easy reading. Other sysfs attributes already include a
newline.
[root@localhost ~]# cat /sys/module/pcie_aspm/parameters/policy
[default] performance powersave powersupersave [root@localhost ~]#
Fixes: 7d715a6c1a ("PCI: add PCI Express ASPM support")
Link: https://lore.kernel.org/r/1594972765-10404-1-git-send-email-wangxiongfeng2@huawei.com
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.
In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:
git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
xargs perl -pi -e \
's/\buninitialized_var\(([^\)]+)\)/\1/g;
s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'
drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.
No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.
[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/
Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
PCIe correctable errors are recovered by hardware with no need for software
intervention (PCIe r5.0, sec 6.2.2.1).
Reduce the log level of correctable errors from KERN_ERR to KERN_WARNING.
The bug reports below are for correctable error logging. This doesn't fix
the cause of those reports, but it may make the messages less alarming.
[bhelgaas: commit log, use pci_printk() to avoid code duplication]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=201517
Link: https://bugzilla.kernel.org/show_bug.cgi?id=196183
Link: https://lore.kernel.org/r/20200618155511.16009-1-Kangie@footclan.ninja
Signed-off-by: Matt Jolly <Kangie@footclan.ninja>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
aer_correctable_error_string[] and aer_uncorrectable_error_string[] have
descriptions of AER error status bits. Add NULL entries to these tables so
all entries for bits 0-31 are defined. Then we don't have to check for
ARRAY_SIZE() when decoding a status word, which simplifies
__aer_print_error().
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The method struct pci_error_handlers.error_detected() is defined and
documented as taking an 'enum pci_channel_state' for the second argument,
but most drivers use 'pci_channel_state_t' instead.
This 'pci_channel_state_t' is not a typedef for the enum but a typedef for
a bitwise type in order to have better/stricter typechecking.
Consolidate everything by using 'pci_channel_state_t' in the method's
definition, in the related helpers and in the drivers.
Enforce use of 'pci_channel_state_t' by replacing 'enum pci_channel_state'
with an anonymous 'enum'.
Note: Currently, from a typechecking point of view this patch changes
nothing because only the constants defined by the enum are bitwise, not the
enum itself (sparse doesn't have the notion of 'bitwise enum'). This may
change in some not too far future, hence the patch.
[bhelgaas: squash in
https://lore.kernel.org/r/20200702162651.49526-3-luc.vanoostenryck@gmail.comhttps://lore.kernel.org/r/20200702162651.49526-4-luc.vanoostenryck@gmail.com]
Link: https://lore.kernel.org/r/20200702162651.49526-2-luc.vanoostenryck@gmail.com
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Replace http:// links with https:// links. This reduces the likelihood of
man-in-the-middle attacks when developers open these links.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
[bhelgaas: also update samsung.com links, drop sourceforge link]
Link: https://lore.kernel.org/r/20200627103050.71712-1-grandmaster@al2klimov.de
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The PCI config accessors (pci_read_config_word(), et al) return
PCIBIOS_SUCCESSFUL (zero) or positive error values like
PCIBIOS_FUNC_NOT_SUPPORTED.
The PCIe capability accessors (pcie_capability_read_word(), et al)
similarly return PCIBIOS errors, but some callers assume they return
generic errno values like -EINVAL.
For example, the Myri-10G probe function returns a positive PCIBIOS error
if the pcie_capability_clear_and_set_word() in pcie_set_readrq() fails:
myri10ge_probe
status = pcie_set_readrq
return pcie_capability_clear_and_set_word
if (status)
return status
A positive return from a PCI driver probe function would cause a "Driver
probe function unexpectedly returned" warning from local_pci_probe()
instead of the desired probe failure.
Convert PCIBIOS errors to generic errno for all callers of:
pcie_capability_read_word
pcie_capability_read_dword
pcie_capability_write_word
pcie_capability_write_dword
pcie_capability_set_word
pcie_capability_set_dword
pcie_capability_clear_word
pcie_capability_clear_dword
pcie_capability_clear_and_set_word
pcie_capability_clear_and_set_dword
that check the return code for anything other than zero.
[bhelgaas: commit log, squash together]
Suggested-by: Bjorn Helgaas <bjorn@helgaas.com>
Link: https://lore.kernel.org/r/20200615073225.24061-1-refactormyself@gmail.com
Signed-off-by: Bolarinwa Olayemi Saheed <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
