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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /Documentation/ABI/testing/sysfs-bus-counter
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
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+What: /sys/bus/counter/devices/counterX/countY/count
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Count data of Count Y represented as a string.
+
+What: /sys/bus/counter/devices/counterX/countY/capture
+KernelVersion: 6.1
+Contact: linux-iio@vger.kernel.org
+Description:
+ Historical capture of the Count Y count data.
+
+What: /sys/bus/counter/devices/counterX/countY/ceiling
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Count value ceiling for Count Y. This is the upper limit for the
+ respective counter.
+
+What: /sys/bus/counter/devices/counterX/countY/floor
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Count value floor for Count Y. This is the lower limit for the
+ respective counter.
+
+What: /sys/bus/counter/devices/counterX/countY/count_mode
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Count mode for channel Y. The ceiling and floor values for
+ Count Y are used by the count mode where required. The following
+ count modes are available:
+
+ normal:
+ Counting is continuous in either direction.
+
+ range limit:
+ An upper or lower limit is set, mimicking limit switches
+ in the mechanical counterpart. The upper limit is set to
+ the Count Y ceiling value, while the lower limit is set
+ to the Count Y floor value. The counter freezes at
+ count = ceiling when counting up, and at count = floor
+ when counting down. At either of these limits, the
+ counting is resumed only when the count direction is
+ reversed.
+
+ non-recycle:
+ The counter is disabled whenever a counter overflow or
+ underflow takes place. The counter is re-enabled when a
+ new count value is loaded to the counter via a preset
+ operation or direct write.
+
+ modulo-n:
+ A count value boundary is set between the Count Y floor
+ value and the Count Y ceiling value. The counter is
+ reset to the Count Y floor value at count = ceiling when
+ counting up, while the counter is set to the Count Y
+ ceiling value at count = floor when counting down; the
+ counter does not freeze at the boundary points, but
+ counts continuously throughout.
+
+What: /sys/bus/counter/devices/counterX/countY/count_mode_available
+What: /sys/bus/counter/devices/counterX/countY/error_noise_available
+What: /sys/bus/counter/devices/counterX/countY/function_available
+What: /sys/bus/counter/devices/counterX/countY/prescaler_available
+What: /sys/bus/counter/devices/counterX/countY/signalZ_action_available
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Discrete set of available values for the respective Count Y
+ configuration are listed in this file. Values are delimited by
+ newline characters.
+
+What: /sys/bus/counter/devices/counterX/countY/direction
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Read-only attribute that indicates the count direction of Count
+ Y. Two count directions are available: forward and backward.
+
+ Some counter devices are able to determine the direction of
+ their counting. For example, quadrature encoding counters can
+ determine the direction of movement by evaluating the leading
+ phase of the respective A and B quadrature encoding signals.
+ This attribute exposes such count directions.
+
+What: /sys/bus/counter/devices/counterX/countY/enable
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Whether channel Y counter is enabled. Valid attribute values are
+ boolean.
+
+ This attribute is intended to serve as a pause/unpause mechanism
+ for Count Y. Suppose a counter device is used to count the total
+ movement of a conveyor belt: this attribute allows an operator
+ to temporarily pause the counter, service the conveyor belt,
+ and then finally unpause the counter to continue where it had
+ left off.
+
+What: /sys/bus/counter/devices/counterX/countY/error_noise
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Read-only attribute that indicates whether excessive noise is
+ present at the channel Y counter inputs.
+
+What: /sys/bus/counter/devices/counterX/countY/function
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Count function mode of Count Y; count function evaluation is
+ triggered by conditions specified by the Count Y signalZ_action
+ attributes. The following count functions are available:
+
+ increase:
+ Accumulated count is incremented.
+
+ decrease:
+ Accumulated count is decremented.
+
+ pulse-direction:
+ Rising edges on signal A updates the respective count.
+ The input level of signal B determines direction.
+
+ quadrature x1 a:
+ If direction is forward, rising edges on quadrature pair
+ signal A updates the respective count; if the direction
+ is backward, falling edges on quadrature pair signal A
+ updates the respective count. Quadrature encoding
+ determines the direction.
+
+ quadrature x1 b:
+ If direction is forward, rising edges on quadrature pair
+ signal B updates the respective count; if the direction
+ is backward, falling edges on quadrature pair signal B
+ updates the respective count. Quadrature encoding
+ determines the direction.
+
+ quadrature x2 a:
+ Any state transition on quadrature pair signal A updates
+ the respective count. Quadrature encoding determines the
+ direction.
+
+ quadrature x2 b:
+ Any state transition on quadrature pair signal B updates
+ the respective count. Quadrature encoding determines the
+ direction.
+
+ quadrature x4:
+ Any state transition on either quadrature pair signals
+ updates the respective count. Quadrature encoding
+ determines the direction.
+
+What: /sys/bus/counter/devices/counterX/countY/name
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Read-only attribute that indicates the device-specific name of
+ Count Y. If possible, this should match the name of the
+ respective channel as it appears in the device datasheet.
+
+What: /sys/bus/counter/devices/counterX/countY/prescaler
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Configure the prescaler value associated with Count Y.
+ On the FlexTimer, the counter clock source passes through a
+ prescaler (i.e. a counter). This acts like a clock
+ divider.
+
+What: /sys/bus/counter/devices/counterX/countY/preset
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ If the counter device supports preset registers -- registers
+ used to load counter channels to a set count upon device-defined
+ preset operation trigger events -- the preset count for channel
+ Y is provided by this attribute.
+
+What: /sys/bus/counter/devices/counterX/countY/preset_enable
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Whether channel Y counter preset operation is enabled. Valid
+ attribute values are boolean.
+
+What: /sys/bus/counter/devices/counterX/countY/signalZ_action
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Action mode of Count Y for Signal Z. This attribute indicates
+ the condition of Signal Z that triggers the count function
+ evaluation for Count Y. The following action modes are
+ available:
+
+ none:
+ Signal does not trigger the count function. In
+ Pulse-Direction count function mode, this Signal is
+ evaluated as Direction.
+
+ rising edge:
+ Low state transitions to high state.
+
+ falling edge:
+ High state transitions to low state.
+
+ both edges:
+ Any state transition.
+
+What: /sys/bus/counter/devices/counterX/countY/num_overflows
+KernelVersion: 6.1
+Contact: linux-iio@vger.kernel.org
+Description:
+ This attribute indicates the number of overflows of count Y.
+
+What: /sys/bus/counter/devices/counterX/countY/capture_component_id
+What: /sys/bus/counter/devices/counterX/countY/ceiling_component_id
+What: /sys/bus/counter/devices/counterX/countY/floor_component_id
+What: /sys/bus/counter/devices/counterX/countY/count_mode_component_id
+What: /sys/bus/counter/devices/counterX/countY/direction_component_id
+What: /sys/bus/counter/devices/counterX/countY/enable_component_id
+What: /sys/bus/counter/devices/counterX/countY/error_noise_component_id
+What: /sys/bus/counter/devices/counterX/countY/prescaler_component_id
+What: /sys/bus/counter/devices/counterX/countY/preset_component_id
+What: /sys/bus/counter/devices/counterX/countY/preset_enable_component_id
+What: /sys/bus/counter/devices/counterX/countY/signalZ_action_component_id
+What: /sys/bus/counter/devices/counterX/countY/num_overflows_component_id
+What: /sys/bus/counter/devices/counterX/signalY/cable_fault_component_id
+What: /sys/bus/counter/devices/counterX/signalY/cable_fault_enable_component_id
+What: /sys/bus/counter/devices/counterX/signalY/filter_clock_prescaler_component_id
+What: /sys/bus/counter/devices/counterX/signalY/index_polarity_component_id
+What: /sys/bus/counter/devices/counterX/signalY/polarity_component_id
+What: /sys/bus/counter/devices/counterX/signalY/synchronous_mode_component_id
+What: /sys/bus/counter/devices/counterX/signalY/frequency_component_id
+KernelVersion: 5.16
+Contact: linux-iio@vger.kernel.org
+Description:
+ Read-only attribute that indicates the component ID of the
+ respective extension or Synapse.
+
+What: /sys/bus/counter/devices/counterX/countY/spike_filter_ns
+KernelVersion: 5.14
+Contact: linux-iio@vger.kernel.org
+Description:
+ If the counter device supports programmable spike filter this
+ attribute indicates the value in nanoseconds where noise pulses
+ shorter or equal to configured value are ignored. Value 0 means
+ filter is disabled.
+
+What: /sys/bus/counter/devices/counterX/events_queue_size
+KernelVersion: 5.16
+Contact: linux-iio@vger.kernel.org
+Description:
+ Size of the Counter events queue in number of struct
+ counter_event data structures. The number of elements will be
+ rounded-up to a power of 2.
+
+What: /sys/bus/counter/devices/counterX/name
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Read-only attribute that indicates the device-specific name of
+ the Counter. This should match the name of the device as it
+ appears in its respective datasheet.
+
+What: /sys/bus/counter/devices/counterX/num_counts
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Read-only attribute that indicates the total number of Counts
+ belonging to the Counter.
+
+What: /sys/bus/counter/devices/counterX/num_signals
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Read-only attribute that indicates the total number of Signals
+ belonging to the Counter.
+
+What: /sys/bus/counter/devices/counterX/signalY/cable_fault
+KernelVersion: 5.7
+Contact: linux-iio@vger.kernel.org
+Description:
+ Read-only attribute that indicates whether a differential
+ encoder cable fault (not connected or loose wires) is detected
+ for the respective channel of Signal Y. Valid attribute values
+ are boolean. Detection must first be enabled via the
+ corresponding cable_fault_enable attribute.
+
+What: /sys/bus/counter/devices/counterX/signalY/cable_fault_enable
+KernelVersion: 5.7
+Contact: linux-iio@vger.kernel.org
+Description:
+ Whether detection of differential encoder cable faults for the
+ respective channel of Signal Y is enabled. Valid attribute
+ values are boolean.
+
+What: /sys/bus/counter/devices/counterX/signalY/filter_clock_prescaler
+KernelVersion: 5.7
+Contact: linux-iio@vger.kernel.org
+Description:
+ Filter clock factor for input Signal Y. This prescaler value
+ affects the inputs of both quadrature pair signals.
+
+What: /sys/bus/counter/devices/counterX/signalY/index_polarity
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Active level of index input Signal Y; irrelevant in
+ non-synchronous load mode.
+
+What: /sys/bus/counter/devices/counterX/signalY/index_polarity_available
+What: /sys/bus/counter/devices/counterX/signalY/synchronous_mode_available
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Discrete set of available values for the respective Signal Y
+ configuration are listed in this file.
+
+What: /sys/bus/counter/devices/counterX/signalY/polarity
+KernelVersion: 6.1
+Contact: linux-iio@vger.kernel.org
+Description:
+ Active level of Signal Y. The following polarity values are
+ available:
+
+ positive:
+ Signal high state considered active level (rising edge).
+
+ negative:
+ Signal low state considered active level (falling edge).
+
+What: /sys/bus/counter/devices/counterX/signalY/name
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Read-only attribute that indicates the device-specific name of
+ Signal Y. If possible, this should match the name of the
+ respective signal as it appears in the device datasheet.
+
+What: /sys/bus/counter/devices/counterX/signalY/signal
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Signal level state of Signal Y. The following signal level
+ states are available:
+
+ low:
+ Low level state.
+
+ high:
+ High level state.
+
+What: /sys/bus/counter/devices/counterX/signalY/synchronous_mode
+KernelVersion: 5.2
+Contact: linux-iio@vger.kernel.org
+Description:
+ Configure the counter associated with Signal Y for
+ non-synchronous or synchronous load mode. Synchronous load mode
+ cannot be selected in non-quadrature (Pulse-Direction) clock
+ mode.
+
+ non-synchronous:
+ A logic low level is the active level at this index
+ input. The index function (as enabled via preset_enable)
+ is performed directly on the active level of the index
+ input.
+
+ synchronous:
+ Intended for interfacing with encoder Index output in
+ quadrature clock mode. The active level is configured
+ via index_polarity. The index function (as enabled via
+ preset_enable) is performed synchronously with the
+ quadrature clock on the active level of the index input.
+
+What: /sys/bus/counter/devices/counterX/signalY/frequency
+KernelVersion: 6.1
+Contact: linux-iio@vger.kernel.org
+Description:
+ Read-only attribute that indicates the signal Y frequency, in Hz.