diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2025-10-06 10:41:03 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2025-10-06 10:41:03 -0700 |
| commit | 2f2c7254931f41b5736e3ba12aaa9ac1bbeeeb92 (patch) | |
| tree | e9d9aa57eceb8f57ef3a88ec99a05d34c947ea83 /Documentation | |
| parent | e4c0fdd5af4c590ca07880b97e286c6532437658 (diff) | |
| parent | 51204faa4273a64b7066b5c1b5383e9b20d58caa (diff) | |
Merge tag 'pci-v6.18-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci
Pull pci updates from Bjorn Helgaas:
"Enumeration:
- Add PCI_FIND_NEXT_CAP() and PCI_FIND_NEXT_EXT_CAP() macros that
take config space accessor functions.
Implement pci_find_capability(), pci_find_ext_capability(), and
dwc, dwc endpoint, and cadence capability search interfaces with
them (Hans Zhang)
- Leave parent unit address 0 in 'interrupt-map' so that when we
build devicetree nodes to describe PCI functions that contain
multiple peripherals, we can build this property even when
interrupt controllers lack 'reg' properties (Lorenzo Pieralisi)
- Add a Xeon 6 quirk to disable Extended Tags and limit Max Read
Request Size to 128B to avoid a performance issue (Ilpo Järvinen)
- Add sysfs 'serial_number' file to expose the Device Serial Number
(Matthew Wood)
- Fix pci_acpi_preserve_config() memory leak (Nirmoy Das)
Resource management:
- Align m68k pcibios_enable_device() with other arches (Ilpo
Järvinen)
- Remove sparc pcibios_enable_device() implementations that don't do
anything beyond what pci_enable_resources() does (Ilpo Järvinen)
- Remove mips pcibios_enable_resources() and use
pci_enable_resources() instead (Ilpo Järvinen)
- Clean up bridge window sizing and assignment (Ilpo Järvinen),
including:
- Leave non-claimed bridge windows disabled
- Enable bridges even if a window wasn't assigned because not all
windows are required by downstream devices
- Preserve bridge window type when releasing the resource, since
the type is needed for reassignment
- Consolidate selection of bridge windows into two new
interfaces, pbus_select_window() and
pbus_select_window_for_type(), so this is done consistently
- Compute bridge window start and end earlier to avoid logging
stale information
MSI:
- Add quirk to disable MSI on RDC PCI to PCIe bridges (Marcos Del Sol
Vives)
Error handling:
- Align AER with EEH by allowing drivers to request a Bus Reset on
Non-Fatal Errors (in addition to the reset on Fatal Errors that we
already do) (Lukas Wunner)
- If error recovery fails, emit FAILED_RECOVERY uevents for the
devices, not for the bridge leading to them.
This makes them correspond to BEGIN_RECOVERY uevents (Lukas Wunner)
- Align AER with EEH by calling err_handler.error_detected()
callbacks to notify drivers if error recovery fails (Lukas Wunner)
- Align AER with EEH by restoring device error_state to
pci_channel_io_normal before the err_handler.slot_reset() callback.
This is earlier than before the err_handler.resume() callback
(Lukas Wunner)
- Emit a BEGIN_RECOVERY uevent when driver's
err_handler.error_detected() requests a reset, as well as when it
says recovery is complete or can be done without a reset (Niklas
Schnelle)
- Align s390 with AER and EEH by emitting uevents during error
recovery (Niklas Schnelle)
- Align EEH with AER and s390 by emitting BEGIN_RECOVERY,
SUCCESSFUL_RECOVERY, or FAILED_RECOVERY uevents depending on the
result of err_handler.error_detected() (Niklas Schnelle)
- Fix a NULL pointer dereference in aer_ratelimit() when ACPI GHES
error information identifies a device without an AER Capability
(Breno Leitao)
- Update error decoding and TLP Log printing for new errors in
current PCIe base spec (Lukas Wunner)
- Update error recovery documentation to match the current code
and use consistent nomenclature (Lukas Wunner)
ASPM:
- Enable all ClockPM and ASPM states for devicetree platforms, since
there's typically no firmware that enables ASPM
This is a risky change that may uncover hardware or configuration
defects at boot-time rather than when users enable ASPM via sysfs
later. Booting with "pcie_aspm=off" prevents this enabling
(Manivannan Sadhasivam)
- Remove the qcom code that enabled ASPM (Manivannan Sadhasivam)
Power management:
- If a device has already been disconnected, e.g., by a hotplug
removal, don't bother trying to resume it to D0 when detaching the
driver.
This avoids annoying "Unable to change power state from D3cold to
D0" messages (Mario Limonciello)
- Ensure devices are powered up before config reads for
'max_link_width', 'current_link_speed', 'current_link_width',
'secondary_bus_number', and 'subordinate_bus_number' sysfs files.
This prevents using invalid data (~0) in drivers or lspci and,
depending on how the PCIe controller reports errors, may avoid
error interrupts or crashes (Brian Norris)
Virtualization:
- Add rescan/remove locking when enabling/disabling SR-IOV, which
avoids list corruption on s390, where disabling SR-IOV also
generates hotplug events (Niklas Schnelle)
Peer-to-peer DMA:
- Free struct p2p_pgmap, not a member within it, in the
pci_p2pdma_add_resource() error path (Sungho Kim)
Endpoint framework:
- Document sysfs interface for BAR assignment of vNTB endpoint
functions (Jerome Brunet)
- Fix array underflow in endpoint BAR test case (Dan Carpenter)
- Skip endpoint IRQ test if the IRQ is out of range to avoid false
errors (Christian Bruel)
- Fix endpoint test case for controllers with fixed-size BARs smaller
than requested by the test (Marek Vasut)
- Restore inbound translation when disabling doorbell so the endpoint
doorbell test case can be run more than once (Niklas Cassel)
- Avoid a NULL pointer dereference when releasing DMA channels in
endpoint DMA test case (Shin'ichiro Kawasaki)
- Convert tegra194 interrupt number to MSI vector to fix endpoint
Kselftest MSI_TEST test case (Niklas Cassel)
- Reset tegra194 BARs when running in endpoint mode so the BAR tests
don't overwrite the ATU settings in BAR4 (Niklas Cassel)
- Handle errors in tegra194 BPMP transactions so we don't mistakenly
skip future PERST# assertion (Vidya Sagar)
AMD MDB PCIe controller driver:
- Update DT binding example to separate PERST# to a Root Port stanza
to make multiple Root Ports possible in the future (Sai Krishna
Musham)
- Add driver support for PERST# being described in a Root Port
stanza, falling back to the host bridge if not found there (Sai
Krishna Musham)
Freescale i.MX6 PCIe controller driver:
- Enable the 3.3V Vaux supply if available so devices can request
wakeup with either Beacon or WAKE# (Richard Zhu)
MediaTek PCIe Gen3 controller driver:
- Add optional sys clock ready time setting to avoid sys_clk_rdy
signal glitching in MT6991 and MT8196 (AngeloGioacchino Del Regno)
- Add DT binding and driver support for MT6991 and MT8196
(AngeloGioacchino Del Regno)
NVIDIA Tegra PCIe controller driver:
- When asserting PERST#, disable the controller instead of mistakenly
disabling the PLL twice (Nagarjuna Kristam)
- Convert struct tegra_msi mask_lock to raw spinlock to avoid a lock
nesting error (Marek Vasut)
Qualcomm PCIe controller driver:
- Select PCI Power Control Slot driver so slot voltage rails can be
turned on/off if described in Root Port devicetree node (Qiang Yu)
- Parse only PCI bridge child nodes in devicetree, skipping unrelated
nodes such as OPP (Operating Performance Points), which caused
probe failures (Krishna Chaitanya Chundru)
- Add 8.0 GT/s and 32.0 GT/s equalization settings (Ziyue Zhang)
- Consolidate Root Port 'phy' and 'reset' properties in struct
qcom_pcie_port, regardless of whether we got them from the Root
Port node or the host bridge node (Manivannan Sadhasivam)
- Fetch and map the ELBI register space in the DWC core rather than
in each driver individually (Krishna Chaitanya Chundru)
- Enable ECAM mechanism in DWC core by setting up iATU with 'CFG
Shift Feature' and use this in the qcom driver (Krishna Chaitanya
Chundru)
- Add SM8750 compatible to qcom,pcie-sm8550.yaml (Krishna Chaitanya
Chundru)
- Update qcom,pcie-x1e80100.yaml to allow fifth PCIe host on Qualcomm
Glymur, which is compatible with X1E80100 but doesn't have the
cnoc_sf_axi clock (Qiang Yu)
Renesas R-Car PCIe controller driver:
- Fix a typo that prevented correct PHY initialization (Marek Vasut)
- Add a missing 1ms delay after PWR reset assertion as required by
the V4H manual (Marek Vasut)
- Assure reset has completed before DBI access to avoid SError (Marek
Vasut)
- Fix inverted PHY initialization check, which sometimes led to
timeouts and failure to start the controller (Marek Vasut)
- Pass the correct IRQ domain to generic_handle_domain_irq() to fix a
regression when converting to msi_create_parent_irq_domain()
(Claudiu Beznea)
- Drop the spinlock protecting the PMSR register - it's no longer
required since pci_lock already serializes accesses (Marek Vasut)
- Convert struct rcar_msi mask_lock to raw spinlock to avoid a lock
nesting error (Marek Vasut)
SOPHGO PCIe controller driver:
- Check for existence of struct cdns_pcie.ops before using it to
allow Cadence drivers that don't need to supply ops (Chen Wang)
- Add DT binding and driver for the SOPHGO SG2042 PCIe controller
(Chen Wang)
STMicroelectronics STM32MP25 PCIe controller driver:
- Update pinctrl documentation of initial states and use in runtime
suspend/resume (Christian Bruel)
- Add pinctrl_pm_select_init_state() for use by stm32 driver, which
needs it during resume (Christian Bruel)
- Add devicetree bindings and drivers for the STMicroelectronics
STM32MP25 in host and endpoint modes (Christian Bruel)
Synopsys DesignWare PCIe controller driver:
- Add support for x16 in devicetree 'num-lanes' property (Konrad
Dybcio)
- Verify that if DT specifies a single IRQ for all eDMA channels, it
is named 'dma' (Niklas Cassel)
TI J721E PCIe driver:
- Add MODULE_DEVICE_TABLE() so driver can be autoloaded (Siddharth
Vadapalli)
- Power controller off before configuring the glue layer so the
controller latches the correct values on power-on (Siddharth
Vadapalli)
TI Keystone PCIe controller driver:
- Use devm_request_irq() so 'ks-pcie-error-irq' is freed when driver
exits with error (Siddharth Vadapalli)
- Add Peripheral Virtualization Unit (PVU), which restricts DMA from
PCIe devices to specific regions of host memory, to the ti,am65
binding (Jan Kiszka)
Xilinx NWL PCIe controller driver:
- Clear bootloader E_ECAM_CONTROL before merging in the new driver
value to avoid writing invalid values (Jani Nurminen)"
* tag 'pci-v6.18-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (141 commits)
PCI/AER: Avoid NULL pointer dereference in aer_ratelimit()
MAINTAINERS: Add entry for ST STM32MP25 PCIe drivers
PCI: stm32-ep: Add PCIe Endpoint support for STM32MP25
dt-bindings: PCI: Add STM32MP25 PCIe Endpoint bindings
PCI: stm32: Add PCIe host support for STM32MP25
PCI: xilinx-nwl: Fix ECAM programming
PCI: j721e: Fix incorrect error message in probe()
PCI: keystone: Use devm_request_irq() to free "ks-pcie-error-irq" on exit
dt-bindings: PCI: qcom,pcie-x1e80100: Set clocks minItems for the fifth Glymur PCIe Controller
PCI: dwc: Support 16-lane operation
PCI: Add lockdep assertion in pci_stop_and_remove_bus_device()
PCI/IOV: Add PCI rescan-remove locking when enabling/disabling SR-IOV
PCI: rcar-host: Convert struct rcar_msi mask_lock into raw spinlock
PCI: tegra194: Rename 'root_bus' to 'root_port_bus' in tegra_pcie_downstream_dev_to_D0()
PCI: tegra: Convert struct tegra_msi mask_lock into raw spinlock
PCI: rcar-gen4: Fix inverted break condition in PHY initialization
PCI: rcar-gen4: Assure reset occurs before DBI access
PCI: rcar-gen4: Add missing 1ms delay after PWR reset assertion
PCI: Set up bridge resources earlier
PCI: rcar-host: Drop PMSR spinlock
...
Diffstat (limited to 'Documentation')
15 files changed, 553 insertions, 103 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index 69f952fffec7..92debe879ffb 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -612,3 +612,12 @@ Description: # ls doe_features 0001:01 0001:02 doe_discovery + +What: /sys/bus/pci/devices/.../serial_number +Date: December 2025 +Contact: Matthew Wood <thepacketgeek@gmail.com> +Description: + This is visible only for PCI devices that support the serial + number extended capability. The file is read only and due to + the possible sensitivity of accessible serial numbers, admin + only. diff --git a/Documentation/PCI/endpoint/pci-vntb-howto.rst b/Documentation/PCI/endpoint/pci-vntb-howto.rst index 70d3bc90893f..9a7a2f0a6849 100644 --- a/Documentation/PCI/endpoint/pci-vntb-howto.rst +++ b/Documentation/PCI/endpoint/pci-vntb-howto.rst @@ -90,8 +90,9 @@ of the function device and is populated with the following NTB specific attributes that can be configured by the user:: # ls functions/pci_epf_vntb/func1/pci_epf_vntb.0/ - db_count mw1 mw2 mw3 mw4 num_mws - spad_count + ctrl_bar db_count mw1_bar mw2_bar mw3_bar mw4_bar spad_count + db_bar mw1 mw2 mw3 mw4 num_mws vbus_number + vntb_vid vntb_pid A sample configuration for NTB function is given below:: @@ -100,6 +101,10 @@ A sample configuration for NTB function is given below:: # echo 1 > functions/pci_epf_vntb/func1/pci_epf_vntb.0/num_mws # echo 0x100000 > functions/pci_epf_vntb/func1/pci_epf_vntb.0/mw1 +By default, each construct is assigned a BAR, as needed and in order. +Should a specific BAR setup be required by the platform, BAR may be assigned +to each construct using the related ``XYZ_bar`` entry. + A sample configuration for virtual NTB driver for virtual PCI bus:: # echo 0x1957 > functions/pci_epf_vntb/func1/pci_epf_vntb.0/vntb_vid diff --git a/Documentation/PCI/pci-error-recovery.rst b/Documentation/PCI/pci-error-recovery.rst index 42e1e78353f3..5df481ac6193 100644 --- a/Documentation/PCI/pci-error-recovery.rst +++ b/Documentation/PCI/pci-error-recovery.rst @@ -13,7 +13,7 @@ PCI Error Recovery Many PCI bus controllers are able to detect a variety of hardware PCI errors on the bus, such as parity errors on the data and address buses, as well as SERR and PERR errors. Some of the more advanced -chipsets are able to deal with these errors; these include PCI-E chipsets, +chipsets are able to deal with these errors; these include PCIe chipsets, and the PCI-host bridges found on IBM Power4, Power5 and Power6-based pSeries boxes. A typical action taken is to disconnect the affected device, halting all I/O to it. The goal of a disconnection is to avoid system @@ -108,8 +108,8 @@ A driver does not have to implement all of these callbacks; however, if it implements any, it must implement error_detected(). If a callback is not implemented, the corresponding feature is considered unsupported. For example, if mmio_enabled() and resume() aren't there, then it -is assumed that the driver is not doing any direct recovery and requires -a slot reset. Typically a driver will want to know about +is assumed that the driver does not need these callbacks +for recovery. Typically a driver will want to know about a slot_reset(). The actual steps taken by a platform to recover from a PCI error @@ -122,6 +122,10 @@ A PCI bus error is detected by the PCI hardware. On powerpc, the slot is isolated, in that all I/O is blocked: all reads return 0xffffffff, all writes are ignored. +Similarly, on platforms supporting Downstream Port Containment +(PCIe r7.0 sec 6.2.11), the link to the sub-hierarchy with the +faulting device is disabled. Any device in the sub-hierarchy +becomes inaccessible. STEP 1: Notification -------------------- @@ -141,6 +145,9 @@ shouldn't do any new IOs. Called in task context. This is sort of a All drivers participating in this system must implement this call. The driver must return one of the following result codes: + - PCI_ERS_RESULT_RECOVERED + Driver returns this if it thinks the device is usable despite + the error and does not need further intervention. - PCI_ERS_RESULT_CAN_RECOVER Driver returns this if it thinks it might be able to recover the HW by just banging IOs or if it wants to be given @@ -199,7 +206,25 @@ reset or some such, but not restart operations. This callback is made if all drivers on a segment agree that they can try to recover and if no automatic link reset was performed by the HW. If the platform can't just re-enable IOs without a slot reset or a link reset, it will not call this callback, and -instead will have gone directly to STEP 3 (Link Reset) or STEP 4 (Slot Reset) +instead will have gone directly to STEP 3 (Link Reset) or STEP 4 (Slot Reset). + +.. note:: + + On platforms supporting Advanced Error Reporting (PCIe r7.0 sec 6.2), + the faulting device may already be accessible in STEP 1 (Notification). + Drivers should nevertheless defer accesses to STEP 2 (MMIO Enabled) + to be compatible with EEH on powerpc and with s390 (where devices are + inaccessible until STEP 2). + + On platforms supporting Downstream Port Containment, the link to the + sub-hierarchy with the faulting device is re-enabled in STEP 3 (Link + Reset). Hence devices in the sub-hierarchy are inaccessible until + STEP 4 (Slot Reset). + + For errors such as Surprise Down (PCIe r7.0 sec 6.2.7), the device + may not even be accessible in STEP 4 (Slot Reset). Drivers can detect + accessibility by checking whether reads from the device return all 1's + (PCI_POSSIBLE_ERROR()). .. note:: @@ -234,14 +259,14 @@ The driver should return one of the following result codes: The next step taken depends on the results returned by the drivers. If all drivers returned PCI_ERS_RESULT_RECOVERED, then the platform -proceeds to either STEP3 (Link Reset) or to STEP 5 (Resume Operations). +proceeds to either STEP 3 (Link Reset) or to STEP 5 (Resume Operations). If any driver returned PCI_ERS_RESULT_NEED_RESET, then the platform proceeds to STEP 4 (Slot Reset) STEP 3: Link Reset ------------------ -The platform resets the link. This is a PCI-Express specific step +The platform resets the link. This is a PCIe specific step and is done whenever a fatal error has been detected that can be "solved" by resetting the link. @@ -263,13 +288,13 @@ that is equivalent to what it would be after a fresh system power-on followed by power-on BIOS/system firmware initialization. Soft reset is also known as hot-reset. -Powerpc fundamental reset is supported by PCI Express cards only +Powerpc fundamental reset is supported by PCIe cards only and results in device's state machines, hardware logic, port states and configuration registers to initialize to their default conditions. For most PCI devices, a soft reset will be sufficient for recovery. Optional fundamental reset is provided to support a limited number -of PCI Express devices for which a soft reset is not sufficient +of PCIe devices for which a soft reset is not sufficient for recovery. If the platform supports PCI hotplug, then the reset might be @@ -313,7 +338,7 @@ Result codes: - PCI_ERS_RESULT_DISCONNECT Same as above. -Drivers for PCI Express cards that require a fundamental reset must +Drivers for PCIe cards that require a fundamental reset must set the needs_freset bit in the pci_dev structure in their probe function. For example, the QLogic qla2xxx driver sets the needs_freset bit for certain PCI card types:: diff --git a/Documentation/PCI/pcieaer-howto.rst b/Documentation/PCI/pcieaer-howto.rst index 4b71e2f43ca7..3210c4792978 100644 --- a/Documentation/PCI/pcieaer-howto.rst +++ b/Documentation/PCI/pcieaer-howto.rst @@ -70,16 +70,16 @@ AER error output ---------------- When a PCIe AER error is captured, an error message will be output to -console. If it's a correctable error, it is output as an info message. +console. If it's a correctable error, it is output as a warning message. Otherwise, it is printed as an error. So users could choose different log level to filter out correctable error messages. Below shows an example:: - 0000:50:00.0: PCIe Bus Error: severity=Uncorrected (Fatal), type=Transaction Layer, id=0500(Requester ID) + 0000:50:00.0: PCIe Bus Error: severity=Uncorrectable (Fatal), type=Transaction Layer, (Requester ID) 0000:50:00.0: device [8086:0329] error status/mask=00100000/00000000 - 0000:50:00.0: [20] Unsupported Request (First) - 0000:50:00.0: TLP Header: 04000001 00200a03 05010000 00050100 + 0000:50:00.0: [20] UnsupReq (First) + 0000:50:00.0: TLP Header: 0x04000001 0x00200a03 0x05010000 0x00050100 In the example, 'Requester ID' means the ID of the device that sent the error message to the Root Port. Please refer to PCIe specs for other @@ -138,7 +138,7 @@ error message to the Root Port above it when it captures an error. The Root Port, upon receiving an error reporting message, internally processes and logs the error message in its AER Capability structure. Error information being logged includes storing -the error reporting agent's requestor ID into the Error Source +the error reporting agent's Requester ID into the Error Source Identification Registers and setting the error bits of the Root Error Status Register accordingly. If AER error reporting is enabled in the Root Error Command Register, the Root Port generates an interrupt when an @@ -152,18 +152,6 @@ the device driver. Provide callbacks ----------------- -callback reset_link to reset PCIe link -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -This callback is used to reset the PCIe physical link when a -fatal error happens. The Root Port AER service driver provides a -default reset_link function, but different Upstream Ports might -have different specifications to reset the PCIe link, so -Upstream Port drivers may provide their own reset_link functions. - -Section 3.2.2.2 provides more detailed info on when to call -reset_link. - PCI error-recovery callbacks ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ @@ -174,8 +162,8 @@ when performing error recovery actions. Data struct pci_driver has a pointer, err_handler, to point to pci_error_handlers who consists of a couple of callback function pointers. The AER driver follows the rules defined in -pci-error-recovery.rst except PCIe-specific parts (e.g. -reset_link). Please refer to pci-error-recovery.rst for detailed +pci-error-recovery.rst except PCIe-specific parts (see +below). Please refer to pci-error-recovery.rst for detailed definitions of the callbacks. The sections below specify when to call the error callback functions. @@ -189,10 +177,21 @@ software intervention or any loss of data. These errors do not require any recovery actions. The AER driver clears the device's correctable error status register accordingly and logs these errors. -Non-correctable (non-fatal and fatal) errors -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +Uncorrectable (non-fatal and fatal) errors +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -If an error message indicates a non-fatal error, performing link reset +The AER driver performs a Secondary Bus Reset to recover from +uncorrectable errors. The reset is applied at the port above +the originating device: If the originating device is an Endpoint, +only the Endpoint is reset. If on the other hand the originating +device has subordinate devices, those are all affected by the +reset as well. + +If the originating device is a Root Complex Integrated Endpoint, +there's no port above where a Secondary Bus Reset could be applied. +In this case, the AER driver instead applies a Function Level Reset. + +If an error message indicates a non-fatal error, performing a reset at upstream is not required. The AER driver calls error_detected(dev, pci_channel_io_normal) to all drivers associated within a hierarchy in question. For example:: @@ -204,38 +203,34 @@ Downstream Port B and Endpoint. A driver may return PCI_ERS_RESULT_CAN_RECOVER, PCI_ERS_RESULT_DISCONNECT, or PCI_ERS_RESULT_NEED_RESET, depending on -whether it can recover or the AER driver calls mmio_enabled as next. +whether it can recover without a reset, considers the device unrecoverable +or needs a reset for recovery. If all affected drivers agree that they can +recover without a reset, it is skipped. Should one driver request a reset, +it overrides all other drivers. If an error message indicates a fatal error, kernel will broadcast error_detected(dev, pci_channel_io_frozen) to all drivers within -a hierarchy in question. Then, performing link reset at upstream is -necessary. As different kinds of devices might use different approaches -to reset link, AER port service driver is required to provide the -function to reset link via callback parameter of pcie_do_recovery() -function. If reset_link is not NULL, recovery function will use it -to reset the link. If error_detected returns PCI_ERS_RESULT_CAN_RECOVER -and reset_link returns PCI_ERS_RESULT_RECOVERED, the error handling goes -to mmio_enabled. - -Frequent Asked Questions ------------------------- +a hierarchy in question. Then, performing a reset at upstream is +necessary. If error_detected returns PCI_ERS_RESULT_CAN_RECOVER +to indicate that recovery without a reset is possible, the error +handling goes to mmio_enabled, but afterwards a reset is still +performed. -Q: - What happens if a PCIe device driver does not provide an - error recovery handler (pci_driver->err_handler is equal to NULL)? +In other words, for non-fatal errors, drivers may opt in to a reset. +But for fatal errors, they cannot opt out of a reset, based on the +assumption that the link is unreliable. -A: - The devices attached with the driver won't be recovered. If the - error is fatal, kernel will print out warning messages. Please refer - to section 3 for more information. +Frequently Asked Questions +-------------------------- Q: - What happens if an upstream port service driver does not provide - callback reset_link? + What happens if a PCIe device driver does not provide an + error recovery handler (pci_driver->err_handler is equal to NULL)? A: - Fatal error recovery will fail if the errors are reported by the - upstream ports who are attached by the service driver. + The devices attached with the driver won't be recovered. + The kernel will print out informational messages to identify + unrecoverable devices. Software error injection diff --git a/Documentation/devicetree/bindings/pci/amd,versal2-mdb-host.yaml b/Documentation/devicetree/bindings/pci/amd,versal2-mdb-host.yaml index 43dc2585c237..406c15e1dee1 100644 --- a/Documentation/devicetree/bindings/pci/amd,versal2-mdb-host.yaml +++ b/Documentation/devicetree/bindings/pci/amd,versal2-mdb-host.yaml @@ -71,6 +71,17 @@ properties: - "#address-cells" - "#interrupt-cells" +patternProperties: + '^pcie@[0-2],0$': + type: object + $ref: /schemas/pci/pci-pci-bridge.yaml# + + properties: + reg: + maxItems: 1 + + unevaluatedProperties: false + required: - reg - reg-names @@ -87,6 +98,7 @@ examples: - | #include <dt-bindings/interrupt-controller/arm-gic.h> #include <dt-bindings/interrupt-controller/irq.h> + #include <dt-bindings/gpio/gpio.h> soc { #address-cells = <2>; @@ -112,10 +124,20 @@ examples: #size-cells = <2>; #interrupt-cells = <1>; device_type = "pci"; + + pcie@0,0 { + device_type = "pci"; + reg = <0x0 0x0 0x0 0x0 0x0>; + reset-gpios = <&tca6416_u37 7 GPIO_ACTIVE_LOW>; + #address-cells = <3>; + #size-cells = <2>; + ranges; + }; + pcie_intc_0: interrupt-controller { #address-cells = <0>; #interrupt-cells = <1>; interrupt-controller; - }; + }; }; }; diff --git a/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml b/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml index 162406e0691a..0278845701ce 100644 --- a/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml +++ b/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml @@ -52,7 +52,12 @@ properties: - mediatek,mt8188-pcie - mediatek,mt8195-pcie - const: mediatek,mt8192-pcie + - items: + - enum: + - mediatek,mt6991-pcie + - const: mediatek,mt8196-pcie - const: mediatek,mt8192-pcie + - const: mediatek,mt8196-pcie - const: airoha,en7581-pcie reg: @@ -217,6 +222,36 @@ allOf: compatible: contains: enum: + - mediatek,mt8196-pcie + then: + properties: + clocks: + minItems: 6 + + clock-names: + items: + - const: pl_250m + - const: tl_26m + - const: bus + - const: low_power + - const: peri_26m + - const: peri_mem + + resets: + minItems: 2 + + reset-names: + items: + - const: phy + - const: mac + + mediatek,pbus-csr: false + + - if: + properties: + compatible: + contains: + enum: - mediatek,mt7986-pcie then: properties: diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie-sa8255p.yaml b/Documentation/devicetree/bindings/pci/qcom,pcie-sa8255p.yaml index ef705a02fcd9..bdddd4f499d1 100644 --- a/Documentation/devicetree/bindings/pci/qcom,pcie-sa8255p.yaml +++ b/Documentation/devicetree/bindings/pci/qcom,pcie-sa8255p.yaml @@ -77,46 +77,46 @@ examples: #size-cells = <2>; pci@1c00000 { - compatible = "qcom,pcie-sa8255p"; - reg = <0x4 0x00000000 0 0x10000000>; - device_type = "pci"; - #address-cells = <3>; - #size-cells = <2>; - ranges = <0x02000000 0x0 0x40100000 0x0 0x40100000 0x0 0x1ff00000>, - <0x43000000 0x4 0x10100000 0x4 0x10100000 0x0 0x40000000>; - bus-range = <0x00 0xff>; - dma-coherent; - linux,pci-domain = <0>; - power-domains = <&scmi5_pd 0>; - iommu-map = <0x0 &pcie_smmu 0x0000 0x1>, - <0x100 &pcie_smmu 0x0001 0x1>; - interrupt-parent = <&intc>; - interrupts = <GIC_SPI 307 IRQ_TYPE_LEVEL_HIGH>, - <GIC_SPI 308 IRQ_TYPE_LEVEL_HIGH>, - <GIC_SPI 309 IRQ_TYPE_LEVEL_HIGH>, - <GIC_SPI 312 IRQ_TYPE_LEVEL_HIGH>, - <GIC_SPI 313 IRQ_TYPE_LEVEL_HIGH>, - <GIC_SPI 314 IRQ_TYPE_LEVEL_HIGH>, - <GIC_SPI 374 IRQ_TYPE_LEVEL_HIGH>, - <GIC_SPI 375 IRQ_TYPE_LEVEL_HIGH>; - interrupt-names = "msi0", "msi1", "msi2", "msi3", - "msi4", "msi5", "msi6", "msi7"; - - #interrupt-cells = <1>; - interrupt-map-mask = <0 0 0 0x7>; - interrupt-map = <0 0 0 1 &intc GIC_SPI 148 IRQ_TYPE_LEVEL_HIGH>, - <0 0 0 2 &intc GIC_SPI 149 IRQ_TYPE_LEVEL_HIGH>, - <0 0 0 3 &intc GIC_SPI 150 IRQ_TYPE_LEVEL_HIGH>, - <0 0 0 4 &intc GIC_SPI 151 IRQ_TYPE_LEVEL_HIGH>; - - pcie@0 { - device_type = "pci"; - reg = <0x0 0x0 0x0 0x0 0x0>; - bus-range = <0x01 0xff>; - - #address-cells = <3>; - #size-cells = <2>; - ranges; + compatible = "qcom,pcie-sa8255p"; + reg = <0x4 0x00000000 0 0x10000000>; + device_type = "pci"; + #address-cells = <3>; + #size-cells = <2>; + ranges = <0x02000000 0x0 0x40100000 0x0 0x40100000 0x0 0x1ff00000>, + <0x43000000 0x4 0x10100000 0x4 0x10100000 0x0 0x40000000>; + bus-range = <0x00 0xff>; + dma-coherent; + linux,pci-domain = <0>; + power-domains = <&scmi5_pd 0>; + iommu-map = <0x0 &pcie_smmu 0x0000 0x1>, + <0x100 &pcie_smmu 0x0001 0x1>; + interrupt-parent = <&intc>; + interrupts = <GIC_SPI 307 IRQ_TYPE_LEVEL_HIGH>, + <GIC_SPI 308 IRQ_TYPE_LEVEL_HIGH>, + <GIC_SPI 309 IRQ_TYPE_LEVEL_HIGH>, + <GIC_SPI 312 IRQ_TYPE_LEVEL_HIGH>, + <GIC_SPI 313 IRQ_TYPE_LEVEL_HIGH>, + <GIC_SPI 314 IRQ_TYPE_LEVEL_HIGH>, + <GIC_SPI 374 IRQ_TYPE_LEVEL_HIGH>, + <GIC_SPI 375 IRQ_TYPE_LEVEL_HIGH>; + interrupt-names = "msi0", "msi1", "msi2", "msi3", + "msi4", "msi5", "msi6", "msi7"; + + #interrupt-cells = <1>; + interrupt-map-mask = <0 0 0 0x7>; + interrupt-map = <0 0 0 1 &intc GIC_SPI 148 IRQ_TYPE_LEVEL_HIGH>, + <0 0 0 2 &intc GIC_SPI 149 IRQ_TYPE_LEVEL_HIGH>, + <0 0 0 3 &intc GIC_SPI 150 IRQ_TYPE_LEVEL_HIGH>, + <0 0 0 4 &intc GIC_SPI 151 IRQ_TYPE_LEVEL_HIGH>; + + pcie@0 { + device_type = "pci"; + reg = <0x0 0x0 0x0 0x0 0x0>; + bus-range = <0x01 0xff>; + + #address-cells = <3>; + #size-cells = <2>; + ranges; }; }; }; diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie-sm8550.yaml b/Documentation/devicetree/bindings/pci/qcom,pcie-sm8550.yaml index dbce671ba011..38b561e23c1f 100644 --- a/Documentation/devicetree/bindings/pci/qcom,pcie-sm8550.yaml +++ b/Documentation/devicetree/bindings/pci/qcom,pcie-sm8550.yaml @@ -22,6 +22,7 @@ properties: - enum: - qcom,sar2130p-pcie - qcom,pcie-sm8650 + - qcom,pcie-sm8750 - const: qcom,pcie-sm8550 reg: diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie-x1e80100.yaml b/Documentation/devicetree/bindings/pci/qcom,pcie-x1e80100.yaml index 257068a18264..61581ffbfb24 100644 --- a/Documentation/devicetree/bindings/pci/qcom,pcie-x1e80100.yaml +++ b/Documentation/devicetree/bindings/pci/qcom,pcie-x1e80100.yaml @@ -32,10 +32,11 @@ properties: - const: mhi # MHI registers clocks: - minItems: 7 + minItems: 6 maxItems: 7 clock-names: + minItems: 6 items: - const: aux # Auxiliary clock - const: cfg # Configuration clock diff --git a/Documentation/devicetree/bindings/pci/sophgo,sg2042-pcie-host.yaml b/Documentation/devicetree/bindings/pci/sophgo,sg2042-pcie-host.yaml new file mode 100644 index 000000000000..f8b7ca57fff1 --- /dev/null +++ b/Documentation/devicetree/bindings/pci/sophgo,sg2042-pcie-host.yaml @@ -0,0 +1,64 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/pci/sophgo,sg2042-pcie-host.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Sophgo SG2042 PCIe Host (Cadence PCIe Wrapper) + +description: + Sophgo SG2042 PCIe host controller is based on the Cadence PCIe core. + +maintainers: + - Chen Wang <unicorn_wang@outlook.com> + +properties: + compatible: + const: sophgo,sg2042-pcie-host + + reg: + maxItems: 2 + + reg-names: + items: + - const: reg + - const: cfg + + vendor-id: + const: 0x1f1c + + device-id: + const: 0x2042 + + msi-parent: true + +allOf: + - $ref: cdns-pcie-host.yaml# + +required: + - compatible + - reg + - reg-names + +unevaluatedProperties: false + +examples: + - | + #include <dt-bindings/interrupt-controller/irq.h> + + pcie@62000000 { + compatible = "sophgo,sg2042-pcie-host"; + device_type = "pci"; + reg = <0x62000000 0x00800000>, + <0x48000000 0x00001000>; + reg-names = "reg", "cfg"; + #address-cells = <3>; + #size-cells = <2>; + ranges = <0x81000000 0 0x00000000 0xde000000 0 0x00010000>, + <0x82000000 0 0xd0400000 0xd0400000 0 0x0d000000>; + bus-range = <0x00 0xff>; + vendor-id = <0x1f1c>; + device-id = <0x2042>; + cdns,no-bar-match-nbits = <48>; + msi-parent = <&msi>; + }; diff --git a/Documentation/devicetree/bindings/pci/st,stm32-pcie-common.yaml b/Documentation/devicetree/bindings/pci/st,stm32-pcie-common.yaml new file mode 100644 index 000000000000..5adbff259204 --- /dev/null +++ b/Documentation/devicetree/bindings/pci/st,stm32-pcie-common.yaml @@ -0,0 +1,33 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/pci/st,stm32-pcie-common.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: STM32MP25 PCIe RC/EP controller + +maintainers: + - Christian Bruel <christian.bruel@foss.st.com> + +description: + STM32MP25 PCIe RC/EP common properties + +properties: + clocks: + maxItems: 1 + description: PCIe system clock + + resets: + maxItems: 1 + + power-domains: + maxItems: 1 + + access-controllers: + maxItems: 1 + +required: + - clocks + - resets + +additionalProperties: true diff --git a/Documentation/devicetree/bindings/pci/st,stm32-pcie-ep.yaml b/Documentation/devicetree/bindings/pci/st,stm32-pcie-ep.yaml new file mode 100644 index 000000000000..b076ada4f332 --- /dev/null +++ b/Documentation/devicetree/bindings/pci/st,stm32-pcie-ep.yaml @@ -0,0 +1,73 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/pci/st,stm32-pcie-ep.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: STMicroelectronics STM32MP25 PCIe Endpoint + +maintainers: + - Christian Bruel <christian.bruel@foss.st.com> + +description: + PCIe endpoint controller based on the Synopsys DesignWare PCIe core. + +allOf: + - $ref: /schemas/pci/snps,dw-pcie-ep.yaml# + - $ref: /schemas/pci/st,stm32-pcie-common.yaml# + +properties: + compatible: + const: st,stm32mp25-pcie-ep + + reg: + items: + - description: Data Bus Interface (DBI) registers. + - description: Data Bus Interface (DBI) shadow registers. + - description: Internal Address Translation Unit (iATU) registers. + - description: PCIe configuration registers. + + reg-names: + items: + - const: dbi + - const: dbi2 + - const: atu + - const: addr_space + + reset-gpios: + description: GPIO controlled connection to PERST# signal + maxItems: 1 + + phys: + maxItems: 1 + +required: + - phys + - reset-gpios + +unevaluatedProperties: false + +examples: + - | + #include <dt-bindings/clock/st,stm32mp25-rcc.h> + #include <dt-bindings/gpio/gpio.h> + #include <dt-bindings/phy/phy.h> + #include <dt-bindings/reset/st,stm32mp25-rcc.h> + + pcie-ep@48400000 { + compatible = "st,stm32mp25-pcie-ep"; + reg = <0x48400000 0x400000>, + <0x48500000 0x100000>, + <0x48700000 0x80000>, + <0x10000000 0x10000000>; + reg-names = "dbi", "dbi2", "atu", "addr_space"; + clocks = <&rcc CK_BUS_PCIE>; + phys = <&combophy PHY_TYPE_PCIE>; + resets = <&rcc PCIE_R>; + pinctrl-names = "default", "init"; + pinctrl-0 = <&pcie_pins_a>; + pinctrl-1 = <&pcie_init_pins_a>; + reset-gpios = <&gpioj 8 GPIO_ACTIVE_LOW>; + access-controllers = <&rifsc 68>; + power-domains = <&CLUSTER_PD>; + }; diff --git a/Documentation/devicetree/bindings/pci/st,stm32-pcie-host.yaml b/Documentation/devicetree/bindings/pci/st,stm32-pcie-host.yaml new file mode 100644 index 000000000000..443bfe2cdc98 --- /dev/null +++ b/Documentation/devicetree/bindings/pci/st,stm32-pcie-host.yaml @@ -0,0 +1,112 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/pci/st,stm32-pcie-host.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: STMicroelectronics STM32MP25 PCIe Root Complex + +maintainers: + - Christian Bruel <christian.bruel@foss.st.com> + +description: + PCIe root complex controller based on the Synopsys DesignWare PCIe core. + +allOf: + - $ref: /schemas/pci/snps,dw-pcie.yaml# + - $ref: /schemas/pci/st,stm32-pcie-common.yaml# + +properties: + compatible: + const: st,stm32mp25-pcie-rc + + reg: + items: + - description: Data Bus Interface (DBI) registers. + - description: PCIe configuration registers. + + reg-names: + items: + - const: dbi + - const: config + + msi-parent: + maxItems: 1 + +patternProperties: + '^pcie@[0-2],0$': + type: object + $ref: /schemas/pci/pci-pci-bridge.yaml# + + properties: + reg: + maxItems: 1 + + phys: + maxItems: 1 + + reset-gpios: + description: GPIO controlled connection to PERST# signal + maxItems: 1 + + wake-gpios: + description: GPIO used as WAKE# input signal + maxItems: 1 + + required: + - phys + - ranges + + unevaluatedProperties: false + +required: + - interrupt-map + - interrupt-map-mask + - ranges + - dma-ranges + +unevaluatedProperties: false + +examples: + - | + #include <dt-bindings/clock/st,stm32mp25-rcc.h> + #include <dt-bindings/gpio/gpio.h> + #include <dt-bindings/interrupt-controller/arm-gic.h> + #include <dt-bindings/phy/phy.h> + #include <dt-bindings/reset/st,stm32mp25-rcc.h> + + pcie@48400000 { + compatible = "st,stm32mp25-pcie-rc"; + device_type = "pci"; + reg = <0x48400000 0x400000>, + <0x10000000 0x10000>; + reg-names = "dbi", "config"; + #interrupt-cells = <1>; + interrupt-map-mask = <0 0 0 7>; + interrupt-map = <0 0 0 1 &intc 0 0 GIC_SPI 264 IRQ_TYPE_LEVEL_HIGH>, + <0 0 0 2 &intc 0 0 GIC_SPI 265 IRQ_TYPE_LEVEL_HIGH>, + <0 0 0 3 &intc 0 0 GIC_SPI 266 IRQ_TYPE_LEVEL_HIGH>, + <0 0 0 4 &intc 0 0 GIC_SPI 267 IRQ_TYPE_LEVEL_HIGH>; + #address-cells = <3>; + #size-cells = <2>; + ranges = <0x01000000 0x0 0x00000000 0x10010000 0x0 0x10000>, + <0x02000000 0x0 0x10020000 0x10020000 0x0 0x7fe0000>, + <0x42000000 0x0 0x18000000 0x18000000 0x0 0x8000000>; + dma-ranges = <0x42000000 0x0 0x80000000 0x80000000 0x0 0x80000000>; + clocks = <&rcc CK_BUS_PCIE>; + resets = <&rcc PCIE_R>; + msi-parent = <&v2m0>; + access-controllers = <&rifsc 68>; + power-domains = <&CLUSTER_PD>; + + pcie@0,0 { + device_type = "pci"; + reg = <0x0 0x0 0x0 0x0 0x0>; + phys = <&combophy PHY_TYPE_PCIE>; + wake-gpios = <&gpioh 5 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>; + reset-gpios = <&gpioj 8 GPIO_ACTIVE_LOW>; + #address-cells = <3>; + #size-cells = <2>; + ranges; + }; + }; diff --git a/Documentation/devicetree/bindings/pci/ti,am65-pci-host.yaml b/Documentation/devicetree/bindings/pci/ti,am65-pci-host.yaml index 0a9d10532cc8..98f6c7f1b1a6 100644 --- a/Documentation/devicetree/bindings/pci/ti,am65-pci-host.yaml +++ b/Documentation/devicetree/bindings/pci/ti,am65-pci-host.yaml @@ -20,14 +20,18 @@ properties: - ti,keystone-pcie reg: - maxItems: 4 + minItems: 4 + maxItems: 6 reg-names: + minItems: 4 items: - const: app - const: dbics - const: config - const: atu + - const: vmap_lp + - const: vmap_hp interrupts: maxItems: 1 @@ -69,6 +73,15 @@ properties: items: pattern: '^pcie-phy[0-1]$' + memory-region: + maxItems: 1 + description: | + phandle to a restricted DMA pool to be used for all devices behind + this controller. The regions should be defined according to + reserved-memory/shared-dma-pool.yaml. + Note that enforcement via the PVU will only be available to + ti,am654-pcie-rc devices. + required: - compatible - reg @@ -89,6 +102,13 @@ then: - power-domains - msi-map - num-viewport +else: + properties: + reg: + maxItems: 4 + + reg-names: + maxItems: 4 unevaluatedProperties: false @@ -104,8 +124,10 @@ examples: reg = <0x5500000 0x1000>, <0x5501000 0x1000>, <0x10000000 0x2000>, - <0x5506000 0x1000>; - reg-names = "app", "dbics", "config", "atu"; + <0x5506000 0x1000>, + <0x2900000 0x1000>, + <0x2908000 0x1000>; + reg-names = "app", "dbics", "config", "atu", "vmap_lp", "vmap_hp"; power-domains = <&k3_pds 120 TI_SCI_PD_EXCLUSIVE>; #address-cells = <3>; #size-cells = <2>; diff --git a/Documentation/driver-api/pin-control.rst b/Documentation/driver-api/pin-control.rst index afc6ddd80fa1..1f585ecca63c 100644 --- a/Documentation/driver-api/pin-control.rst +++ b/Documentation/driver-api/pin-control.rst @@ -1162,8 +1162,55 @@ pinmux core. Pin control requests from drivers ================================= -When a device driver is about to probe the device core will automatically -attempt to issue ``pinctrl_get_select_default()`` on these devices. +When a device driver is about to probe, the device core attaches the +standard states if they are defined in the device tree by calling +``pinctrl_bind_pins()`` on these devices. +Possible standard state names are: "default", "init", "sleep" and "idle". + +- if ``default`` is defined in the device tree, it is selected before + device probe. + +- if ``init`` and ``default`` are defined in the device tree, the "init" + state is selected before the driver probe and the "default" state is + selected after the driver probe. + +- the ``sleep`` and ``idle`` states are for power management and can only + be selected with the PM API bellow. + +PM interfaces +================= +PM runtime suspend/resume might need to execute the same init sequence as +during probe. Since the predefined states are already attached to the +device, the driver can activate these states explicitly with the +following helper functions: + +- ``pinctrl_pm_select_default_state()`` +- ``pinctrl_pm_select_init_state()`` +- ``pinctrl_pm_select_sleep_state()`` +- ``pinctrl_pm_select_idle_state()`` + +For example, if resuming the device depend on certain pinmux states + +.. code-block:: c + + foo_suspend() + { + /* suspend device */ + ... + + pinctrl_pm_select_sleep_state(dev); + } + + foo_resume() + { + pinctrl_pm_select_init_state(dev); + + /* resuming device */ + ... + + pinctrl_pm_select_default_state(dev); + } + This way driver writers do not need to add any of the boilerplate code of the type found below. However when doing fine-grained state selection and not using the "default" state, you may have to do some device driver @@ -1185,6 +1232,12 @@ operation and going to sleep, moving from the ``PINCTRL_STATE_DEFAULT`` to ``PINCTRL_STATE_SLEEP`` at runtime, re-biasing or even re-muxing pins to save current in sleep mode. +Another case is when the pinctrl needs to switch to a certain mode during +probe and then revert to the default state at the end of probe. For example +a PINMUX may need to be configured as a GPIO during probe. In this case, use +``PINCTRL_STATE_INIT`` to switch state before probe, then move to +``PINCTRL_STATE_DEFAULT`` at the end of probe for normal operation. + A driver may request a certain control state to be activated, usually just the default state like this: |
