- Add PCI_ERROR_RESPONSE and related definitions for signaling and checking
for transaction errors on PCI (Naveen Naidu)
- Fabricate PCI_ERROR_RESPONSE data (~0) in config read wrappers, instead
of in host controller drivers, when transactions fail on PCI (Naveen
Naidu)
- Use PCI_POSSIBLE_ERROR() to check for possible failure of config reads
(Naveen Naidu)
* pci/errors:
PCI: xgene: Use PCI_ERROR_RESPONSE to identify config read errors
PCI: hv: Use PCI_ERROR_RESPONSE to identify config read errors
PCI: keystone: Use PCI_ERROR_RESPONSE to identify config read errors
PCI: Use PCI_ERROR_RESPONSE to identify config read errors
PCI: cpqphp: Use PCI_POSSIBLE_ERROR() to check config reads
PCI/PME: Use PCI_POSSIBLE_ERROR() to check config reads
PCI/DPC: Use PCI_POSSIBLE_ERROR() to check config reads
PCI: pciehp: Use PCI_POSSIBLE_ERROR() to check config reads
PCI: vmd: Use PCI_POSSIBLE_ERROR() to check config reads
PCI/ERR: Use PCI_POSSIBLE_ERROR() to check config reads
PCI: rockchip-host: Drop error data fabrication when config read fails
PCI: rcar-host: Drop error data fabrication when config read fails
PCI: altera: Drop error data fabrication when config read fails
PCI: mvebu: Drop error data fabrication when config read fails
PCI: aardvark: Drop error data fabrication when config read fails
PCI: kirin: Drop error data fabrication when config read fails
PCI: histb: Drop error data fabrication when config read fails
PCI: exynos: Drop error data fabrication when config read fails
PCI: mediatek: Drop error data fabrication when config read fails
PCI: iproc: Drop error data fabrication when config read fails
PCI: thunder: Drop error data fabrication when config read fails
PCI: Drop error data fabrication when config read fails
PCI: Use PCI_SET_ERROR_RESPONSE() for disconnected devices
PCI: Set error response data when config read fails
PCI: Add PCI_ERROR_RESPONSE and related definitions
- Use pci_find_vsec_capability() instead of open-coding it (Andy
Shevchenko)
- Convert pci_dev_present() stub from macro to static inline to avoid
'unused variable' errors (Hans de Goede)
- Convert sysfs slot attributes from default_attrs to default_groups (Greg
Kroah-Hartman)
- Use DWORD accesses for LTR, L1 SS to avoid BayHub OZ711LV2 erratum (Rajat
Jain)
- Remove unnecessary initialization of static variables (Longji Guo)
* pci/enumeration:
x86/PCI: Remove initialization of static variables to false
PCI: Use DWORD accesses for LTR, L1 SS to avoid erratum
PCI/sysfs: Use default_groups in kobj_type for slot attrs
PCI: Convert pci_dev_present() stub to static inline
PCI: Use pci_find_vsec_capability() when looking for TBT devices
Some devices have an erratum such that they only support DWORD accesses to
some registers. E.g., this Bayhub O2 device ([VID:DID] = [0x1217:0x8621])
only supports DWORD accesses to LTR latency registers and L1 PM substates
control registers:
https://github.com/rajatxjain/public_shared/blob/main/OZ711LV2_appnote.pdf
The L1 PM substate control registers are DWORD sized, and hence their
access in the kernel is already DWORD sized, so we don't need to do
anything for them.
However, the LTR registers being WORD sized, are in need of a solution.
Convert the WORD sized accesses to these registers into DWORD sized
accesses while saving and restoring them.
Link: https://lore.kernel.org/r/20211222012105.3438916-1-rajatja@google.com
Signed-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The struct aspm_latency is now used only inside pcie_aspm_check_latency().
Replace struct aspm_latency variables with u32 variables and remove struct
aspm_latency.
Link: https://lore.kernel.org/r/20211119193732.12343-5-refactormyself@gmail.com
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Previously we calculated the device's acceptable L0s and L1 exit latencies
in pcie_aspm_cap_init() and cached them in struct pcie_link_state.
These values are only used in pcie_aspm_check_latency() where they are
compared with the actual exit latencies of the link. This path is used
when removing or changing the D state of the device, so it's relatively low
frequency.
To reduce the amount of per-link data we store, remove the acceptable[]
arrays from struct pcie_link_state and calculate them directly from the
already-cached Device Capabilities register when needed.
[bhelgaas: use endpoint->devcap instead of reading it again]
Link: https://lore.kernel.org/r/20211119193732.12343-4-refactormyself@gmail.com
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously we calculated the upstream and downstream L0s and L1 exit
latencies of the link in pcie_aspm_cap_init() and cached them in struct
pcie_link_state.latency_*.
These values are only used in pcie_aspm_check_latency() where they are
compared with the acceptable latencies on the link. This path is used when
removing or changing the D state of the device, so it's relatively low
frequency.
To reduce the amount of per-link data we store, remove the latency_*
entries from struct pcie_link_state and calculate the latencies directly
where they are needed.
Link: https://lore.kernel.org/r/20211119193732.12343-3-refactormyself@gmail.com
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Move pci_function_0() earlier so we can use it from other functions.
Link: https://lore.kernel.org/r/20211119193732.12343-2-refactormyself@gmail.com
Signed-off-by: Bolarinwa O. Saheed <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When config pci_ops.read() can detect failed PCI transactions, the data
returned to the CPU is PCI_ERROR_RESPONSE (~0 or 0xffffffff).
Obviously a successful PCI config read may *also* return that data if a
config register happens to contain ~0, so it doesn't definitively indicate
an error unless we know the register cannot contain ~0.
Use PCI_POSSIBLE_ERROR() to check the response we get when we read data
from hardware. This unifies PCI error response checking and makes error
checks consistent and easier to find.
Compile tested only.
Link: https://lore.kernel.org/r/679ce049bccf10df3ca9ef4918ee2c3235afdaea.1637243717.git.naveennaidu479@gmail.com
Signed-off-by: Naveen Naidu <naveennaidu479@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
When config pci_ops.read() can detect failed PCI transactions, the data
returned to the CPU is PCI_ERROR_RESPONSE (~0 or 0xffffffff).
Obviously a successful PCI config read may *also* return that data if a
config register happens to contain ~0, so it doesn't definitively indicate
an error unless we know the register cannot contain ~0.
Use PCI_POSSIBLE_ERROR() to check the response we get when we read data
from hardware. This unifies PCI error response checking and makes error
checks consistent and easier to find.
Compile tested only.
Link: https://lore.kernel.org/r/9b0632f1f183432149f495cf12bdd5a72cc597a4.1637243717.git.naveennaidu479@gmail.com
Signed-off-by: Naveen Naidu <naveennaidu479@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This reverts commit 2a4d9408c9.
Robert reported a NULL pointer dereference caused by the PCI core
(local_pci_probe()) calling the i2c_designware_pci driver's
.runtime_resume() method before the .probe() method. i2c_dw_pci_resume()
depends on initialization done by i2c_dw_pci_probe().
Prior to 2a4d9408c9 ("PCI: Use to_pci_driver() instead of
pci_dev->driver"), pci_pm_runtime_resume() avoided calling the
.runtime_resume() method because pci_dev->driver had not been set yet.
2a4d9408c9 and b5f9c644eb ("PCI: Remove struct pci_dev->driver"),
removed pci_dev->driver, replacing it by device->driver, which *has* been
set by this time, so pci_pm_runtime_resume() called the .runtime_resume()
method when it previously had not.
Fixes: 2a4d9408c9 ("PCI: Use to_pci_driver() instead of pci_dev->driver")
Link: https://lore.kernel.org/linux-i2c/CAP145pgdrdiMAT7=-iB1DMgA7t_bMqTcJL4N0=6u8kNY3EU0dw@mail.gmail.com/
Reported-by: Robert Święcki <robert@swiecki.net>
Tested-by: Robert Święcki <robert@swiecki.net>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
- Tidy setup-irq.c comments (Pranay Sanghai)
- Fix misspellings (Krzysztof Wilczyński)
- Fix sprintf(), sscanf() format mismatches (Krzysztof Wilczyński)
- Tidy cpqphp code formatting (Krzysztof Wilczyński)
- Remove unused pci_pool wrappers, which have been replaced by dma_pool
(Cai Huoqing)
- Remove a redundant initialization in __pci_reset_function_locked() (Colin
Ian King)
- Use 'unsigned int' instead of 'unsigned' (Krzysztof Wilczyński)
- Update PCI subsystem information in MAINTAINERS (Krzysztof Wilczyński)
- Include generic <linux/> headers instead of <asm/> for cpqphp and vmd
(Krzysztof Wilczyński)
* pci/misc:
PCI: vmd: Drop redundant includes of <asm/device.h>, <asm/msi.h>
PCI: cpqphp: Use <linux/io.h> instead of <asm/io.h>
MAINTAINERS: Update PCI subsystem information
PCI: Prefer 'unsigned int' over bare 'unsigned'
PCI: Remove redundant 'rc' initialization
PCI: Remove unused pci_pool wrappers
PCI: cpqphp: Format if-statement code block correctly
PCI: Use unsigned to match sscanf("%x") in pci_dev_str_match_path()
PCI: hv: Remove unnecessary use of %hx
PCI: Correct misspelled and remove duplicated words
PCI: Tidy comments
- Check for CAP_SYS_ADMIN before validating sysfs user input, not after
(Krzysztof Wilczyński)
- Always return -EINVAL from sysfs "store" functions for invalid user input
instead of -EINVAL sometimes and -ERANGE others (Krzysztof Wilczyński)
- Use kstrtobool() directly instead of the strtobool() wrapper (Krzysztof
Wilczyński)
* pci/sysfs:
PCI: Use kstrtobool() directly, sans strtobool() wrapper
PCI/sysfs: Return -EINVAL consistently from "store" functions
PCI/sysfs: Check CAP_SYS_ADMIN before parsing user input
# Conflicts:
# drivers/pci/iov.c
- Don't setup portdrv IRQs if there are no port drivers that use them, to
conserve vectors and avoid spurious events (Jan Kiszka)
* pci/portdrv:
PCI/portdrv: Do not setup up IRQs if there are no users
- Ignore Link Down/Up caused by error-induced Hot Reset so endpoint driver
can remain bound to device during error recovery (Lukas Wunner)
- Remove unused resume err_handler (Lukas Wunner)
- Remove unused pcie_port_bus_{,un}register() declarations (Lukas Wunner)
- Skip compiling err.c when CONFIG_PCIEAER not set (Lukas Wunner)
* pci/hotplug:
PCI/ERR: Reduce compile time for CONFIG_PCIEAER=n
PCI/portdrv: Remove unused pcie_port_bus_{,un}register() declarations
PCI/portdrv: Remove unused resume err_handler
PCI: pciehp: Ignore Link Down/Up caused by error-induced Hot Reset
PCI/portdrv: Rename pm_iter() to pcie_port_device_iter()
Struct pci_driver contains a struct device_driver, so for PCI devices, it's
easy to convert a device_driver * to a pci_driver * with to_pci_driver().
The device_driver * is in struct device, so we don't need to also keep
track of the pci_driver * in struct pci_dev.
Replace pci_dev->driver with to_pci_driver(). This is a step toward
removing pci_dev->driver.
[bhelgaas: split to separate patch]
Link: https://lore.kernel.org/r/20211004125935.2300113-11-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The sole non-static function in err.c, pcie_do_recovery(), is only
called from:
* aer.c (if CONFIG_PCIEAER=y)
* dpc.c (if CONFIG_PCIE_DPC=y, which depends on CONFIG_PCIEAER)
* edr.c (if CONFIG_PCIE_EDR=y, which depends on CONFIG_PCIE_DPC)
Thus, err.c need not be compiled if CONFIG_PCIEAER=n.
Also, pci_uevent_ers() and pcie_clear_device_status(), which are called
from err.c, can be #ifdef'ed away unless CONFIG_PCIEAER=y.
Since x86_64_defconfig doesn't enable CONFIG_PCIEAER, this change may
slightly reduce compile time for anyone doing a test build with that
config.
Link: https://lore.kernel.org/r/98f9041151268c1c035ab64cca320ad86803f64a.1627638184.git.lukas@wunner.de
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Commit 3e41a317ae ("PCI/AER: Remove unused aer_error_resume()")
removed the resume err_handler from AER. Since no other port service
implements the callback, support for it can be removed from portdrv.
It can be revived later if need be, preferably by re-using the
pcie_port_device_iter() iterator.
Link: https://lore.kernel.org/r/25334149b604e005058aeb0fdf51e01f991d5d74.1627638184.git.lukas@wunner.de
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Keith Busch <kbusch@kernel.org>
Stuart Hayes reports that an error handled by DPC at a Root Port results
in pciehp gratuitously bringing down a subordinate hotplug port:
RP -- UP -- DP -- UP -- DP (hotplug) -- EP
pciehp brings the slot down because the Link to the Endpoint goes down.
That is caused by a Hot Reset being propagated as a result of DPC.
Per PCIe Base Spec 5.0, section 6.6.1 "Conventional Reset":
For a Switch, the following must cause a hot reset to be sent on all
Downstream Ports: [...]
* The Data Link Layer of the Upstream Port reporting DL_Down status.
In Switches that support Link speeds greater than 5.0 GT/s, the
Upstream Port must direct the LTSSM of each Downstream Port to the
Hot Reset state, but not hold the LTSSMs in that state. This permits
each Downstream Port to begin Link training immediately after its
hot reset completes. This behavior is recommended for all Switches.
* Receiving a hot reset on the Upstream Port.
Once DPC recovers, pcie_do_recovery() walks down the hierarchy and
invokes pcie_portdrv_slot_reset() to restore each port's config space.
At that point, a hotplug interrupt is signaled per PCIe Base Spec r5.0,
section 6.7.3.4 "Software Notification of Hot-Plug Events":
If the Port is enabled for edge-triggered interrupt signaling using
MSI or MSI-X, an interrupt message must be sent every time the logical
AND of the following conditions transitions from FALSE to TRUE: [...]
* The Hot-Plug Interrupt Enable bit in the Slot Control register is
set to 1b.
* At least one hot-plug event status bit in the Slot Status register
and its associated enable bit in the Slot Control register are both
set to 1b.
Prevent pciehp from gratuitously bringing down the slot by clearing the
error-induced Data Link Layer State Changed event before restoring
config space. Afterwards, check whether the link has unexpectedly
failed to retrain and synthesize a DLLSC event if so.
Allow each pcie_port_service_driver (one of them being pciehp) to define
a slot_reset callback and re-use the existing pm_iter() function to
iterate over the callbacks.
Thereby, the Endpoint driver remains bound throughout error recovery and
may restore the device to working state.
Surprise removal during error recovery is detected through a Presence
Detect Changed event. The hotplug port is expected to not signal that
event as a result of a Hot Reset.
The issue isn't DPC-specific, it also occurs when an error is handled by
AER through aer_root_reset(). So while the issue was noticed only now,
it's been around since 2006 when AER support was first introduced.
[bhelgaas: drop PCI_ERROR_RECOVERY Kconfig, split pm_iter() rename to
preparatory patch]
Link: https://lore.kernel.org/linux-pci/08c046b0-c9f2-3489-eeef-7e7aca435bb9@gmail.com/
Fixes: 6c2b374d74 ("PCI-Express AER implemetation: AER core and aerdriver")
Link: https://lore.kernel.org/r/251f4edcc04c14f873ff1c967bc686169cd07d2d.1627638184.git.lukas@wunner.de
Reported-by: Stuart Hayes <stuart.w.hayes@gmail.com>
Tested-by: Stuart Hayes <stuart.w.hayes@gmail.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org # v2.6.19+: ba952824e6c1: PCI/portdrv: Report reset for frozen channel
Cc: Keith Busch <kbusch@kernel.org>
Save the struct pci_driver pointer from pdev->driver instead of repeating
it several times. No functional change.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Correct a number of misspelled words and remove any words that were
duplicated in the PCI tree. No change to functionality intended.
Link: https://lore.kernel.org/r/20211006233827.147328-1-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
strtobool() is a wrapper around kstrtobool() that has been added for
backward compatibility.
There is no reason to use the old API, so use kstrtobool() directly.
Related: ef95159907 ("lib: move strtobool() to kstrtobool()")
Link: https://lore.kernel.org/r/20210915230127.2495723-3-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Avoid registering service IRQs if there is no service that offers them
or no driver to register a handler against them. This saves IRQ vectors
when they are limited (e.g. on x86) and also avoids that spurious events
could hit a missing handler. Such spurious events need to be generated
by the Jailhouse hypervisor for active MSI vectors when enabling or
disabling itself.
Link: https://lore.kernel.org/r/8f9a13ac-8ab1-15ac-06cb-c131b488a36f@siemens.com
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
- Cache PCIe Device Capabilities register (Amey Narkhede)
- Add pcie_reset_flr() with 'probe' argument (Amey Narkhede)
- Add pdev->reset_methods[] array to track reset method ordering (Amey
Narkhede)
- Remove reset_fn field from pci_dev (Amey Narkhede)
- Add sysfs interface to query and set device reset mechanism (Amey
Narkhede)
- Add pci_set_acpi_fwnode() to set ACPI_COMPANION (Shanker Donthineni)
- Use acpi_pci_power_manageable() instead of duplicating logic (Shanker
Donthineni)
- Set ACPI fwnode early and at the same time with OF (Shanker Donthineni)
- Add support for ACPI _RST reset method (Shanker Donthineni)
- Change reset function 'probe' argument to bool (Amey Narkhede)
* pci/reset:
PCI: Change the type of probe argument in reset functions
PCI: Add support for ACPI _RST reset method
PCI: Setup ACPI fwnode early and at the same time with OF
PCI: Use acpi_pci_power_manageable()
PCI: Add pci_set_acpi_fwnode() to set ACPI_COMPANION
PCI: Allow userspace to query and set device reset mechanism
PCI: Remove reset_fn field from pci_dev
PCI: Add array to track reset method ordering
PCI: Add pcie_reset_flr() with 'probe' argument
PCI: Cache PCIe Device Capabilities register
Previously we assumed that all Root Ports and Switch Downstream Ports
supported Link Bandwidth Notification. Per spec, this is only required
for Ports supporting Links wider than x1 and/or multiple Link speeds
(PCIe r5.0, sec 7.5.3.6).
Because we assumed all Ports supported it, we tried to set up a Bandwidth
Notification IRQ, which failed for devices that don't support IRQs at all,
which meant pcieport didn't attach to the Port at all.
Check the Link Bandwidth Notification Capability bit and enable the service
only when the Port supports it.
[bhelgaas: commit log]
Fixes: e8303bb7a7 ("PCI/LINK: Report degraded links via link bandwidth notification")
Link: https://lore.kernel.org/r/20210512213314.7778-1-stuart.w.hayes@gmail.com
Signed-off-by: Stuart Hayes <stuart.w.hayes@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org
Add a predicate that returns if PCIe PTM (Precision Time Measurement)
is enabled.
It will only return true if it's enabled in all the ports in the path
from the device to the root.
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Since 39850ed510 ("PCI/PTM: Save/restore Precision Time Measurement
Capability for suspend/resume"), devices that have PTM capability but
don't enable it see this message on calls to pci_save_state():
no suspend buffer for PTM
Drop the message, it's perfectly fine not to use a capability.
Fixes: 39850ed510 ("PCI/PTM: Save/restore Precision Time Measurement Capability for suspend/resume")
Link: https://lore.kernel.org/r/20210811185955.3112534-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: David E. Box <david.e.box@linux.intel.com>
Change the type of probe argument in functions which implement reset
methods from int to bool to make the context and intent clear.
Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20210817180500.1253-10-ameynarkhede03@gmail.com
Signed-off-by: Amey Narkhede <ameynarkhede03@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Most reset methods are of the form "pci_*_reset(dev, probe)". pcie_flr()
was an exception because it relied on a separate pcie_has_flr() function
instead of taking a "probe" argument.
Add "pcie_reset_flr(dev, probe)" to follow the convention. Remove
pcie_has_flr().
Some pcie_flr() callers that did not use pcie_has_flr() remain.
[bhelgaas: commit log, rework pcie_reset_flr() to use dev->devcap directly]
Link: https://lore.kernel.org/r/20210817180500.1253-3-ameynarkhede03@gmail.com
Signed-off-by: Amey Narkhede <ameynarkhede03@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
- Ignore pciehp Link Down/Up caused by DPC so device remains bound to
driver (Lukas Wunner)
- Declare global cpci_debug in header file (Krzysztof Wilczyński)
* pci/hotplug:
PCI: cpcihp: Declare cpci_debug in header file
PCI: pciehp: Ignore Link Down/Up caused by DPC
Downstream Port Containment (PCIe r5.0, sec. 6.2.10) disables the link upon
an error and attempts to re-enable it when instructed by the DPC driver.
A slot which is both DPC- and hotplug-capable is currently powered off by
pciehp once DPC is triggered (due to the link change) and powered back up
on successful recovery. That's undesirable, the slot should remain powered
so the hotplugged device remains bound to its driver. DPC notifies the
driver of the error and of successful recovery in pcie_do_recovery() and
the driver may then restore the device to working state.
Moreover, Sinan points out that turning off slot power by pciehp may foil
recovery by DPC: Power off/on is a cold reset concurrently to DPC's warm
reset. Sathyanarayanan reports extended delays or failure in link
retraining by DPC if pciehp brings down the slot.
Fix by detecting whether a Link Down event is caused by DPC and awaiting
recovery if so. On successful recovery, ignore both the Link Down and the
subsequent Link Up event.
Afterwards, check whether the link is down to detect surprise-removal or
another DPC event immediately after DPC recovery. Ensure that the
corresponding DLLSC event is not ignored by synthesizing it and invoking
irq_wake_thread() to trigger a re-run of pciehp_ist().
The IRQ threads of the hotplug and DPC drivers, pciehp_ist() and
dpc_handler(), race against each other. If pciehp is faster than DPC, it
will wait until DPC recovery completes.
Recovery consists of two steps: The first step (waiting for link
disablement) is recognizable by pciehp through a set DPC Trigger Status
bit. The second step (waiting for link retraining) is recognizable through
a newly introduced PCI_DPC_RECOVERING flag.
If DPC is faster than pciehp, neither of the two flags will be set and
pciehp may glean the recovery status from the new PCI_DPC_RECOVERED flag.
The flag is zero if DPC didn't occur at all, hence DLLSC events are not
ignored by default.
pciehp waits up to 4 seconds before assuming that DPC recovery failed and
bringing down the slot. This timeout is not taken from the spec (it
doesn't mandate one) but based on a report from Yicong Yang that DPC may
take a bit more than 3 seconds on HiSilicon's Kunpeng platform.
The timeout is necessary because the DPC Trigger Status bit may never
clear: On Root Ports which support RP Extensions for DPC, the DPC driver
polls the DPC RP Busy bit for up to 1 second before giving up on DPC
recovery. Without the timeout, pciehp would then wait indefinitely for DPC
to complete.
This commit draws inspiration from previous attempts to synchronize DPC
with pciehp:
By Sinan Kaya, August 2018:
https://lore.kernel.org/linux-pci/20180818065126.77912-1-okaya@kernel.org/
By Ethan Zhao, October 2020:
https://lore.kernel.org/linux-pci/20201007113158.48933-1-haifeng.zhao@intel.com/
By Kuppuswamy Sathyanarayanan, March 2021:
https://lore.kernel.org/linux-pci/59cb30f5e5ac6d65427ceaadf1012b2ba8dbf66c.1615606143.git.sathyanarayanan.kuppuswamy@linux.intel.com/
Link: https://lore.kernel.org/r/0be565d97438fe2a6d57354b3aa4e8626952a00b.1619857124.git.lukas@wunner.de
Reported-by: Sinan Kaya <okaya@kernel.org>
Reported-by: Ethan Zhao <haifeng.zhao@intel.com>
Reported-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Tested-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Tested-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Keith Busch <kbusch@kernel.org>
The sysfs_emit() and sysfs_emit_at() functions were introduced to make
it less ambiguous which function is preferred when writing to the output
buffer in a device attribute's "show" callback [1].
Convert the PCI sysfs object "show" functions from sprintf(), snprintf()
and scnprintf() to sysfs_emit() and sysfs_emit_at() accordingly, as the
latter is aware of the PAGE_SIZE buffer and correctly returns the number
of bytes written into the buffer.
No functional change intended.
[1] Documentation/filesystems/sysfs.rst
Related commit: ad025f8e46 ("PCI/sysfs: Use sysfs_emit() and
sysfs_emit_at() in "show" functions").
Link: https://lore.kernel.org/r/20210603000112.703037-2-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
We use format domain🚌slot.function when printing PCI device. Use
consistent format in AER messages.
[bhelgaas: also drop "AER recover:" prefix since we already have an "AER:"
prefix from pr_fmt()]
Link: https://lore.kernel.org/r/1617015721-51701-1-git-send-email-yangyicong@hisilicon.com
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Krzysztof Wilczyński <kw@linux.com>
rcec_assoc_rciep() used "rciep->devfn" (a single byte encoding both the
device and function number) as the device number to check whether the
corresponding bit was set in the RCEC's Association Bitmap for RCiEPs.
But per PCIe r5.0, sec 7.9.10.2, "Association Bitmap for RCiEPs", the
32-bit bitmap contains one bit per device. That bit applies to all
functions of the device.
Fix rcec_assoc_rciep() to convert the value of "rciep->devfn" to a device
number to ensure that RCiEP devices are correctly associated with the RCEC.
Reported-and-tested-by: Wen Jin <wen.jin@intel.com>
Fixes: 507b460f81 ("PCI/ERR: Add pcie_link_rcec() to associate RCiEPs")
Link: https://lore.kernel.org/r/20210222011717.43266-1-qiuxu.zhuo@intel.com
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sean V Kelley <sean.v.kelley@intel.com>
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Merge tag 'pci-v5.12-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI updates from Bjorn Helgaas:
"Enumeration:
- Remove unnecessary locking around _OSC (Bjorn Helgaas)
- Clarify message about _OSC failure (Bjorn Helgaas)
- Remove notification of PCIe bandwidth changes (Bjorn Helgaas)
- Tidy checking of syscall user config accessors (Heiner Kallweit)
Resource management:
- Decline to resize resources if boot config must be preserved (Ard
Biesheuvel)
- Fix pci_register_io_range() memory leak (Geert Uytterhoeven)
Error handling (Keith Busch):
- Clear error status from the correct device
- Retain error recovery status so drivers can use it after reset
- Log the type of Port (Root or Switch Downstream) that we reset
- Always request a reset for Downstream Ports in frozen state
Endpoint framework and NTB (Kishon Vijay Abraham I):
- Make *_get_first_free_bar() take into account 64 bit BAR
- Add helper API to get the 'next' unreserved BAR
- Make *_free_bar() return error codes on failure
- Remove unused pci_epf_match_device()
- Add support to associate secondary EPC with EPF
- Add support in configfs to associate two EPCs with EPF
- Add pci_epc_ops to map MSI IRQ
- Add pci_epf_ops to expose function-specific attrs
- Allow user to create sub-directory of 'EPF Device' directory
- Implement ->msi_map_irq() ops for cadence
- Configure LM_EP_FUNC_CFG based on epc->function_num_map for cadence
- Add EP function driver to provide NTB functionality
- Add support for EPF PCI Non-Transparent Bridge
- Add specification for PCI NTB function device
- Add PCI endpoint NTB function user guide
- Add configfs binding documentation for pci-ntb endpoint function
Broadcom STB PCIe controller driver:
- Add support for BCM4908 and external PERST# signal controller
(Rafał Miłecki)
Cadence PCIe controller driver:
- Retrain Link to work around Gen2 training defect (Nadeem Athani)
- Fix merge botch in cdns_pcie_host_map_dma_ranges() (Krzysztof
Wilczyński)
Freescale Layerscape PCIe controller driver:
- Add LX2160A rev2 EP mode support (Hou Zhiqiang)
- Convert to builtin_platform_driver() (Michael Walle)
MediaTek PCIe controller driver:
- Fix OF node reference leak (Krzysztof Wilczyński)
Microchip PolarFlare PCIe controller driver:
- Add Microchip PolarFire PCIe controller driver (Daire McNamara)
Qualcomm PCIe controller driver:
- Use PHY_REFCLK_USE_PAD only for ipq8064 (Ansuel Smith)
- Add support for ddrss_sf_tbu clock for sm8250 (Dmitry Baryshkov)
Renesas R-Car PCIe controller driver:
- Drop PCIE_RCAR config option (Lad Prabhakar)
- Always allocate MSI addresses in 32bit space (Marek Vasut)
Rockchip PCIe controller driver:
- Add FriendlyARM NanoPi M4B DT binding (Chen-Yu Tsai)
- Make 'ep-gpios' DT property optional (Chen-Yu Tsai)
Synopsys DesignWare PCIe controller driver:
- Work around ECRC configuration hardware defect (Vidya Sagar)
- Drop support for config space in DT 'ranges' (Rob Herring)
- Change size to u64 for EP outbound iATU (Shradha Todi)
- Add upper limit address for outbound iATU (Shradha Todi)
- Make dw_pcie ops optional (Jisheng Zhang)
- Remove unnecessary dw_pcie_ops from al driver (Jisheng Zhang)
Xilinx Versal CPM PCIe controller driver:
- Fix OF node reference leak (Pan Bian)
Miscellaneous:
- Remove tango host controller driver (Arnd Bergmann)
- Remove IRQ handler & data together (altera-msi, brcmstb, dwc)
(Martin Kaiser)
- Fix xgene-msi race in installing chained IRQ handler (Martin
Kaiser)
- Apply CONFIG_PCI_DEBUG to entire drivers/pci hierarchy (Junhao He)
- Fix pci-bridge-emul array overruns (Russell King)
- Remove obsolete uses of WARN_ON(in_interrupt()) (Sebastian Andrzej
Siewior)"
* tag 'pci-v5.12-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (69 commits)
PCI: qcom: Use PHY_REFCLK_USE_PAD only for ipq8064
PCI: qcom: Add support for ddrss_sf_tbu clock
dt-bindings: PCI: qcom: Document ddrss_sf_tbu clock for sm8250
PCI: al: Remove useless dw_pcie_ops
PCI: dwc: Don't assume the ops in dw_pcie always exist
PCI: dwc: Add upper limit address for outbound iATU
PCI: dwc: Change size to u64 for EP outbound iATU
PCI: dwc: Drop support for config space in 'ranges'
PCI: layerscape: Convert to builtin_platform_driver()
PCI: layerscape: Add LX2160A rev2 EP mode support
dt-bindings: PCI: layerscape: Add LX2160A rev2 compatible strings
PCI: dwc: Work around ECRC configuration issue
PCI/portdrv: Report reset for frozen channel
PCI/AER: Specify the type of Port that was reset
PCI/ERR: Retain status from error notification
PCI/AER: Clear AER status from Root Port when resetting Downstream Port
PCI/ERR: Clear status of the reporting device
dt-bindings: arm: rockchip: Add FriendlyARM NanoPi M4B
PCI: rockchip: Make 'ep-gpios' DT property optional
Documentation: PCI: Add PCI endpoint NTB function user guide
...
The PCI error recovery always resets the link for a frozen state, so the
port driver should return that a reset is required for its result. This
will get the .slot_reset() callback invoked, which is necessary to
restore the port's config space. Without this, the driver had been
relying on downstream drivers to return this status.
Link: https://lore.kernel.org/r/20210104230300.1277180-6-kbusch@kernel.org
Tested-by: Hedi Berriche <hedi.berriche@hpe.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Hedi Berriche <hedi.berriche@hpe.com>
The AER driver may be called upon to reset either a Downstream or a Root
Port. Check which type it is to properly identify it when logging that
the reset occurred.
Link: https://lore.kernel.org/r/20210104230300.1277180-5-kbusch@kernel.org
Tested-by: Hedi Berriche <hedi.berriche@hpe.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Hedi Berriche <hedi.berriche@hpe.com>
Overwriting the frozen detected status with the result of the link reset
loses the NEED_RESET result that drivers are depending on for error
handling to report the .slot_reset() callback. Retain this status so
that subsequent error handling has the correct flow.
Link: https://lore.kernel.org/r/20210104230300.1277180-4-kbusch@kernel.org
Reported-by: Hinko Kocevar <hinko.kocevar@ess.eu>
Tested-by: Hedi Berriche <hedi.berriche@hpe.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Sean V Kelley <sean.v.kelley@intel.com>
Acked-by: Hedi Berriche <hedi.berriche@hpe.com>
The pci_dev parameter given to aer_root_reset() may be a Downstream Port
rather than the Root Port. Get the Root Port from the provided device in
order to clear the root's AER status.
Link: https://lore.kernel.org/r/20210104230300.1277180-3-kbusch@kernel.org
Tested-by: Hedi Berriche <hedi.berriche@hpe.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Sean V Kelley <sean.v.kelley@intel.com>
Acked-by: Hedi Berriche <hedi.berriche@hpe.com>
Error handling operates on the first Downstream Port above the detected
error, but the error may have been reported by a downstream device.
Clear the AER status of the device that reported the error rather than
the first Downstream Port.
Link: https://lore.kernel.org/r/20210104230300.1277180-2-kbusch@kernel.org
Tested-by: Hedi Berriche <hedi.berriche@hpe.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Sean V Kelley <sean.v.kelley@intel.com>
Acked-by: Hedi Berriche <hedi.berriche@hpe.com>
The PCIe Bandwidth Change Notification feature logs messages when the link
bandwidth changes. Some users have reported that these messages occur
often enough to significantly reduce NVMe performance. GPUs also seem to
generate these messages.
We don't know why the link bandwidth changes, but in the reported cases
there's no indication that it's caused by hardware failures.
Remove the bandwidth change notifications for now. Hopefully we can add
this back when we have a better understanding of why this happens and how
we can make the messages useful instead of overwhelming.
Link: https://lore.kernel.org/r/20200115221008.GA191037@google.com/
Link: https://lore.kernel.org/r/155605909349.3575.13433421148215616375.stgit@gimli.home/
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206197
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
- 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
Bjorn Helgaas