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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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+.. SPDX-License-Identifier: GPL-2.0
+
+
+AMD Sensor Fusion Hub
+=====================
+AMD Sensor Fusion Hub (SFH) is part of an SOC starting from Ryzen-based platforms.
+The solution is working well on several OEM products. AMD SFH uses HID over PCIe bus.
+In terms of architecture it resembles ISH, however the major difference is all
+the HID reports are generated as part of the kernel driver.
+
+Block Diagram
+-------------
+
+::
+
+ ---------------------------------
+ | HID User Space Applications |
+ - -------------------------------
+
+ ---------------------------------------------
+ ---------------------------------
+ | HID Core |
+ ---------------------------------
+
+ ---------------------------------
+ | AMD HID Transport |
+ ---------------------------------
+
+ --------------------------------
+ | AMD HID Client |
+ | with HID Report Generator|
+ --------------------------------
+
+ --------------------------------
+ | AMD MP2 PCIe Driver |
+ --------------------------------
+ OS
+ ---------------------------------------------
+ Hardware + Firmware
+ --------------------------------
+ | SFH MP2 Processor |
+ --------------------------------
+
+
+AMD HID Transport Layer
+-----------------------
+AMD SFH transport is also implemented as a bus. Each client application executing in the AMD MP2 is
+registered as a device on this bus. Here, MP2 is an ARM core connected to x86 for processing
+sensor data. The layer, which binds each device (AMD SFH HID driver) identifies the device type and
+registers with the HID core. Transport layer attaches a constant "struct hid_ll_driver" object with
+each device. Once a device is registered with HID core, the callbacks provided via this struct are
+used by HID core to communicate with the device. AMD HID Transport layer implements the synchronous calls.
+
+AMD HID Client Layer
+--------------------
+This layer is responsible to implement HID requests and descriptors. As firmware is OS agnostic, HID
+client layer fills the HID request structure and descriptors. HID client layer is complex as it is
+interface between MP2 PCIe layer and HID. HID client layer initializes the MP2 PCIe layer and holds
+the instance of MP2 layer. It identifies the number of sensors connected using MP2-PCIe layer. Based
+on that allocates the DRAM address for each and every sensor and passes it to MP2-PCIe driver. On
+enumeration of each sensor, client layer fills the HID Descriptor structure and HID input report
+structure. HID Feature report structure is optional. The report descriptor structure varies from
+sensor to sensor.
+
+AMD MP2 PCIe layer
+------------------
+MP2 PCIe Layer is responsible for making all transactions with the firmware over PCIe.
+The connection establishment between firmware and PCIe happens here.
+
+The communication between X86 and MP2 is split into three parts.
+1. Command transfer via the C2P mailbox registers.
+2. Data transfer via DRAM.
+3. Supported sensor info via P2C registers.
+
+Commands are sent to MP2 using C2P Mailbox registers. Writing into C2P Message registers generates
+interrupt to MP2. The client layer allocates the physical memory and the same is sent to MP2 via
+the PCI layer. MP2 firmware writes the command output to the access DRAM memory which the client
+layer has allocated. Firmware always writes minimum of 32 bytes into DRAM. So as a protocol driver
+shall allocate minimum of 32 bytes DRAM space.
+
+Enumeration and Probing flow
+----------------------------
+::
+
+ HID AMD AMD AMD -PCIe MP2
+ Core Transport Client layer layer FW
+ | | | | |
+ | | | on Boot Driver Loaded |
+ | | | | |
+ | | | MP2-PCIe Int |
+ | | | | |
+ | | |---Get Number of sensors-> | |
+ | | | Read P2C |
+ | | | Register |
+ | | | | |
+ | | | Loop(for No of Sensors) | |
+ | | |----------------------| | |
+ | | | Create HID Descriptor| | |
+ | | | Create Input report | | |
+ | | | Descriptor Map | | |
+ | | | the MP2 FW Index to | | |
+ | | | HID Index | | |
+ | | | Allocate the DRAM | Enable |
+ | | | address | Sensors |
+ | | |----------------------| | |
+ | | HID transport| | Enable |
+ | |<--Probe------| |---Sensor CMD--> |
+ | | Create the | | |
+ | | HID device | | |
+ | | (MFD) | | |
+ | | by Populating| | |
+ | | the HID | | |
+ | | ll_driver | | |
+ | HID | | | |
+ | add | | | |
+ |Device | | | |
+ |<------------- | | | |
+
+
+Data Flow from Application to the AMD SFH Driver
+------------------------------------------------
+
+::
+
+ | | | | |
+ | | | | |
+ | | | | |
+ | | | | |
+ | | | | |
+ |HID_req | | | |
+ |get_report | | | |
+ |------------->| | | |
+ | | HID_get_input| | |
+ | | report | | |
+ | |------------->|------------------------| | |
+ | | | Read the DRAM data for| | |
+ | | | requested sensor and | | |
+ | | | create the HID input | | |
+ | | | report | | |
+ | | |------------------------| | |
+ | |Data received | | |
+ | | in HID report| | |
+ To |<-------------|<-------------| | |
+ Applications| | | | |
+ <-------| | | | |