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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
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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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+Kernel driver lm85
+==================
+
+Supported chips:
+
+ * National Semiconductor LM85 (B and C versions)
+
+ Prefix: 'lm85b' or 'lm85c'
+
+ Addresses scanned: I2C 0x2c, 0x2d, 0x2e
+
+ Datasheet: http://www.national.com/pf/LM/LM85.html
+
+ * Texas Instruments LM96000
+
+ Prefix: 'lm9600'
+
+ Addresses scanned: I2C 0x2c, 0x2d, 0x2e
+
+ Datasheet: https://www.ti.com/lit/ds/symlink/lm96000.pdf
+
+ * Analog Devices ADM1027
+
+ Prefix: 'adm1027'
+
+ Addresses scanned: I2C 0x2c, 0x2d, 0x2e
+
+ Datasheet: https://www.onsemi.com/PowerSolutions/product.do?id=ADM1027
+
+ * Analog Devices ADT7463
+
+ Prefix: 'adt7463'
+
+ Addresses scanned: I2C 0x2c, 0x2d, 0x2e
+
+ Datasheet: https://www.onsemi.com/PowerSolutions/product.do?id=ADT7463
+
+ * Analog Devices ADT7468
+
+ Prefix: 'adt7468'
+
+ Addresses scanned: I2C 0x2c, 0x2d, 0x2e
+
+ Datasheet: https://www.onsemi.com/PowerSolutions/product.do?id=ADT7468
+
+ * SMSC EMC6D100, SMSC EMC6D101
+
+ Prefix: 'emc6d100'
+
+ Addresses scanned: I2C 0x2c, 0x2d, 0x2e
+
+ Datasheet: http://www.smsc.com/media/Downloads_Public/discontinued/6d100.pdf
+
+ * SMSC EMC6D102
+
+ Prefix: 'emc6d102'
+
+ Addresses scanned: I2C 0x2c, 0x2d, 0x2e
+
+ Datasheet: http://www.smsc.com/main/catalog/emc6d102.html
+
+ * SMSC EMC6D103
+
+ Prefix: 'emc6d103'
+
+ Addresses scanned: I2C 0x2c, 0x2d, 0x2e
+
+ Datasheet: http://www.smsc.com/main/catalog/emc6d103.html
+
+ * SMSC EMC6D103S
+
+ Prefix: 'emc6d103s'
+
+ Addresses scanned: I2C 0x2c, 0x2d, 0x2e
+
+ Datasheet: http://www.smsc.com/main/catalog/emc6d103s.html
+
+Authors:
+ - Philip Pokorny <ppokorny@penguincomputing.com>,
+ - Frodo Looijaard <frodol@dds.nl>,
+ - Richard Barrington <rich_b_nz@clear.net.nz>,
+ - Margit Schubert-While <margitsw@t-online.de>,
+ - Justin Thiessen <jthiessen@penguincomputing.com>
+
+Description
+-----------
+
+This driver implements support for the National Semiconductor LM85 and
+compatible chips including the Analog Devices ADM1027, ADT7463, ADT7468 and
+SMSC EMC6D10x chips family.
+
+The LM85 uses the 2-wire interface compatible with the SMBUS 2.0
+specification. Using an analog to digital converter it measures three (3)
+temperatures and five (5) voltages. It has four (4) 16-bit counters for
+measuring fan speed. Five (5) digital inputs are provided for sampling the
+VID signals from the processor to the VRM. Lastly, there are three (3) PWM
+outputs that can be used to control fan speed.
+
+The voltage inputs have internal scaling resistors so that the following
+voltage can be measured without external resistors:
+
+ 2.5V, 3.3V, 5V, 12V, and CPU core voltage (2.25V)
+
+The temperatures measured are one internal diode, and two remote diodes.
+Remote 1 is generally the CPU temperature. These inputs are designed to
+measure a thermal diode like the one in a Pentium 4 processor in a socket
+423 or socket 478 package. They can also measure temperature using a
+transistor like the 2N3904.
+
+A sophisticated control system for the PWM outputs is designed into the
+LM85 that allows fan speed to be adjusted automatically based on any of the
+three temperature sensors. Each PWM output is individually adjustable and
+programmable. Once configured, the LM85 will adjust the PWM outputs in
+response to the measured temperatures without further host intervention.
+This feature can also be disabled for manual control of the PWM's.
+
+Each of the measured inputs (voltage, temperature, fan speed) has
+corresponding high/low limit values. The LM85 will signal an ALARM if any
+measured value exceeds either limit.
+
+The LM85 samples all inputs continuously. The lm85 driver will not read
+the registers more often than once a second. Further, configuration data is
+only read once each 5 minutes. There is twice as much config data as
+measurements, so this would seem to be a worthwhile optimization.
+
+Special Features
+----------------
+
+The LM85 has four fan speed monitoring modes. The ADM1027 has only two.
+Both have special circuitry to compensate for PWM interactions with the
+TACH signal from the fans. The ADM1027 can be configured to measure the
+speed of a two wire fan, but the input conditioning circuitry is different
+for 3-wire and 2-wire mode. For this reason, the 2-wire fan modes are not
+exposed to user control. The BIOS should initialize them to the correct
+mode. If you've designed your own ADM1027, you'll have to modify the
+init_client function and add an insmod parameter to set this up.
+
+To smooth the response of fans to changes in temperature, the LM85 has an
+optional filter for smoothing temperatures. The ADM1027 has the same
+config option but uses it to rate limit the changes to fan speed instead.
+
+The ADM1027, ADT7463 and ADT7468 have a 10-bit ADC and can therefore
+measure temperatures with 0.25 degC resolution. They also provide an offset
+to the temperature readings that is automatically applied during
+measurement. This offset can be used to zero out any errors due to traces
+and placement. The documentation says that the offset is in 0.25 degC
+steps, but in initial testing of the ADM1027 it was 1.00 degC steps. Analog
+Devices has confirmed this "bug". The ADT7463 is reported to work as
+described in the documentation. The current lm85 driver does not show the
+offset register.
+
+The ADT7468 has a high-frequency PWM mode, where all PWM outputs are
+driven by a 22.5 kHz clock. This is a global mode, not per-PWM output,
+which means that setting any PWM frequency above 11.3 kHz will switch
+all 3 PWM outputs to a 22.5 kHz frequency. Conversely, setting any PWM
+frequency below 11.3 kHz will switch all 3 PWM outputs to a frequency
+between 10 and 100 Hz, which can then be tuned separately.
+
+See the vendor datasheets for more information. There is application note
+from National (AN-1260) with some additional information about the LM85.
+The Analog Devices datasheet is very detailed and describes a procedure for
+determining an optimal configuration for the automatic PWM control.
+
+The SMSC EMC6D100 & EMC6D101 monitor external voltages, temperatures, and
+fan speeds. They use this monitoring capability to alert the system to out
+of limit conditions and can automatically control the speeds of multiple
+fans in a PC or embedded system. The EMC6D101, available in a 24-pin SSOP
+package, and the EMC6D100, available in a 28-pin SSOP package, are designed
+to be register compatible. The EMC6D100 offers all the features of the
+EMC6D101 plus additional voltage monitoring and system control features.
+Unfortunately it is not possible to distinguish between the package
+versions on register level so these additional voltage inputs may read
+zero. EMC6D102 and EMC6D103 feature additional ADC bits thus extending precision
+of voltage and temperature channels.
+
+SMSC EMC6D103S is similar to EMC6D103, but does not support pwm#_auto_pwm_minctl
+and temp#_auto_temp_off.
+
+The LM96000 supports additional high frequency PWM modes (22.5 kHz, 24 kHz,
+25.7 kHz, 27.7 kHz and 30 kHz), which can be configured on a per-PWM basis.
+
+Hardware Configurations
+-----------------------
+
+The LM85 can be jumpered for 3 different SMBus addresses. There are
+no other hardware configuration options for the LM85.
+
+The lm85 driver detects both LM85B and LM85C revisions of the chip. See the
+datasheet for a complete description of the differences. Other than
+identifying the chip, the driver behaves no differently with regard to
+these two chips. The LM85B is recommended for new designs.
+
+The ADM1027, ADT7463 and ADT7468 chips have an optional SMBALERT output
+that can be used to signal the chipset in case a limit is exceeded or the
+temperature sensors fail. Individual sensor interrupts can be masked so
+they won't trigger SMBALERT. The SMBALERT output if configured replaces one
+of the other functions (PWM2 or IN0). This functionality is not implemented
+in current driver.
+
+The ADT7463 and ADT7468 also have an optional THERM output/input which can
+be connected to the processor PROC_HOT output. If available, the autofan
+control dynamic Tmin feature can be enabled to keep the system temperature
+within spec (just?!) with the least possible fan noise.
+
+Configuration Notes
+-------------------
+
+Besides standard interfaces driver adds following:
+
+* Temperatures and Zones
+
+Each temperature sensor is associated with a Zone. There are three
+sensors and therefore three zones (# 1, 2 and 3). Each zone has the following
+temperature configuration points:
+
+* temp#_auto_temp_off
+ - temperature below which fans should be off or spinning very low.
+* temp#_auto_temp_min
+ - temperature over which fans start to spin.
+* temp#_auto_temp_max
+ - temperature when fans spin at full speed.
+* temp#_auto_temp_crit
+ - temperature when all fans will run full speed.
+
+PWM Control
+^^^^^^^^^^^
+
+There are three PWM outputs. The LM85 datasheet suggests that the
+pwm3 output control both fan3 and fan4. Each PWM can be individually
+configured and assigned to a zone for its control value. Each PWM can be
+configured individually according to the following options.
+
+* pwm#_auto_pwm_min
+ - this specifies the PWM value for temp#_auto_temp_off
+ temperature. (PWM value from 0 to 255)
+
+* pwm#_auto_pwm_minctl
+ - this flags selects for temp#_auto_temp_off temperature
+ the behaviour of fans. Write 1 to let fans spinning at
+ pwm#_auto_pwm_min or write 0 to let them off.
+
+.. note::
+
+ It has been reported that there is a bug in the LM85 that causes
+ the flag to be associated with the zones not the PWMs. This
+ contradicts all the published documentation. Setting pwm#_min_ctl
+ in this case actually affects all PWMs controlled by zone '#'.
+
+PWM Controlling Zone selection
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+* pwm#_auto_channels
+ - controls zone that is associated with PWM
+
+Configuration choices:
+
+========== =============================================
+Value Meaning
+========== =============================================
+ 1 Controlled by Zone 1
+ 2 Controlled by Zone 2
+ 3 Controlled by Zone 3
+ 23 Controlled by higher temp of Zone 2 or 3
+ 123 Controlled by highest temp of Zone 1, 2 or 3
+ 0 PWM always 0% (off)
+ -1 PWM always 100% (full on)
+ -2 Manual control (write to 'pwm#' to set)
+========== =============================================
+
+The National LM85's have two vendor specific configuration
+features. Tach. mode and Spinup Control. For more details on these,
+see the LM85 datasheet or Application Note AN-1260. These features
+are not currently supported by the lm85 driver.
+
+The Analog Devices ADM1027 has several vendor specific enhancements.
+The number of pulses-per-rev of the fans can be set, Tach monitoring
+can be optimized for PWM operation, and an offset can be applied to
+the temperatures to compensate for systemic errors in the
+measurements. These features are not currently supported by the lm85
+driver.
+
+In addition to the ADM1027 features, the ADT7463 and ADT7468 also have
+Tmin control and THERM asserted counts. Automatic Tmin control acts to
+adjust the Tmin value to maintain the measured temperature sensor at a
+specified temperature. There isn't much documentation on this feature in
+the ADT7463 data sheet. This is not supported by current driver.