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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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+============================
+ Core Driver Infrastructure
+============================
+
+GPU Hardware Structure
+======================
+
+Each ASIC is a collection of hardware blocks. We refer to them as
+"IPs" (Intellectual Property blocks). Each IP encapsulates certain
+functionality. IPs are versioned and can also be mixed and matched.
+E.g., you might have two different ASICs that both have System DMA (SDMA) 5.x IPs.
+The driver is arranged by IPs. There are driver components to handle
+the initialization and operation of each IP. There are also a bunch
+of smaller IPs that don't really need much if any driver interaction.
+Those end up getting lumped into the common stuff in the soc files.
+The soc files (e.g., vi.c, soc15.c nv.c) contain code for aspects of
+the SoC itself rather than specific IPs. E.g., things like GPU resets
+and register access functions are SoC dependent.
+
+An APU contains more than just CPU and GPU, it also contains all of
+the platform stuff (audio, usb, gpio, etc.). Also, a lot of
+components are shared between the CPU, platform, and the GPU (e.g.,
+SMU, PSP, etc.). Specific components (CPU, GPU, etc.) usually have
+their interface to interact with those common components. For things
+like S0i3 there is a ton of coordination required across all the
+components, but that is probably a bit beyond the scope of this
+section.
+
+With respect to the GPU, we have the following major IPs:
+
+GMC (Graphics Memory Controller)
+ This was a dedicated IP on older pre-vega chips, but has since
+ become somewhat decentralized on vega and newer chips. They now
+ have dedicated memory hubs for specific IPs or groups of IPs. We
+ still treat it as a single component in the driver however since
+ the programming model is still pretty similar. This is how the
+ different IPs on the GPU get the memory (VRAM or system memory).
+ It also provides the support for per process GPU virtual address
+ spaces.
+
+IH (Interrupt Handler)
+ This is the interrupt controller on the GPU. All of the IPs feed
+ their interrupts into this IP and it aggregates them into a set of
+ ring buffers that the driver can parse to handle interrupts from
+ different IPs.
+
+PSP (Platform Security Processor)
+ This handles security policy for the SoC and executes trusted
+ applications, and validates and loads firmwares for other blocks.
+
+SMU (System Management Unit)
+ This is the power management microcontroller. It manages the entire
+ SoC. The driver interacts with it to control power management
+ features like clocks, voltages, power rails, etc.
+
+DCN (Display Controller Next)
+ This is the display controller. It handles the display hardware.
+ It is described in more details in :ref:`Display Core <amdgpu-display-core>`.
+
+SDMA (System DMA)
+ This is a multi-purpose DMA engine. The kernel driver uses it for
+ various things including paging and GPU page table updates. It's also
+ exposed to userspace for use by user mode drivers (OpenGL, Vulkan,
+ etc.)
+
+GC (Graphics and Compute)
+ This is the graphics and compute engine, i.e., the block that
+ encompasses the 3D pipeline and and shader blocks. This is by far the
+ largest block on the GPU. The 3D pipeline has tons of sub-blocks. In
+ addition to that, it also contains the CP microcontrollers (ME, PFP,
+ CE, MEC) and the RLC microcontroller. It's exposed to userspace for
+ user mode drivers (OpenGL, Vulkan, OpenCL, etc.)
+
+VCN (Video Core Next)
+ This is the multi-media engine. It handles video and image encode and
+ decode. It's exposed to userspace for user mode drivers (VA-API,
+ OpenMAX, etc.)
+
+Graphics and Compute Microcontrollers
+-------------------------------------
+
+CP (Command Processor)
+ The name for the hardware block that encompasses the front end of the
+ GFX/Compute pipeline. Consists mainly of a bunch of microcontrollers
+ (PFP, ME, CE, MEC). The firmware that runs on these microcontrollers
+ provides the driver interface to interact with the GFX/Compute engine.
+
+ MEC (MicroEngine Compute)
+ This is the microcontroller that controls the compute queues on the
+ GFX/compute engine.
+
+ MES (MicroEngine Scheduler)
+ This is a new engine for managing queues. This is currently unused.
+
+RLC (RunList Controller)
+ This is another microcontroller in the GFX/Compute engine. It handles
+ power management related functionality within the GFX/Compute engine.
+ The name is a vestige of old hardware where it was originally added
+ and doesn't really have much relation to what the engine does now.
+
+Driver Structure
+================
+
+In general, the driver has a list of all of the IPs on a particular
+SoC and for things like init/fini/suspend/resume, more or less just
+walks the list and handles each IP.
+
+Some useful constructs:
+
+KIQ (Kernel Interface Queue)
+ This is a control queue used by the kernel driver to manage other gfx
+ and compute queues on the GFX/compute engine. You can use it to
+ map/unmap additional queues, etc.
+
+IB (Indirect Buffer)
+ A command buffer for a particular engine. Rather than writing
+ commands directly to the queue, you can write the commands into a
+ piece of memory and then put a pointer to the memory into the queue.
+ The hardware will then follow the pointer and execute the commands in
+ the memory, then returning to the rest of the commands in the ring.
+
+.. _amdgpu_memory_domains:
+
+Memory Domains
+==============
+
+.. kernel-doc:: include/uapi/drm/amdgpu_drm.h
+ :doc: memory domains
+
+Buffer Objects
+==============
+
+.. kernel-doc:: drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
+ :doc: amdgpu_object
+
+.. kernel-doc:: drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
+ :internal:
+
+PRIME Buffer Sharing
+====================
+
+.. kernel-doc:: drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
+ :doc: PRIME Buffer Sharing
+
+.. kernel-doc:: drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
+ :internal:
+
+MMU Notifier
+============
+
+.. kernel-doc:: drivers/gpu/drm/amd/amdgpu/amdgpu_hmm.c
+ :doc: MMU Notifier
+
+.. kernel-doc:: drivers/gpu/drm/amd/amdgpu/amdgpu_hmm.c
+ :internal:
+
+AMDGPU Virtual Memory
+=====================
+
+.. kernel-doc:: drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+ :doc: GPUVM
+
+.. kernel-doc:: drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+ :internal:
+
+Interrupt Handling
+==================
+
+.. kernel-doc:: drivers/gpu/drm/amd/amdgpu/amdgpu_irq.c
+ :doc: Interrupt Handling
+
+.. kernel-doc:: drivers/gpu/drm/amd/amdgpu/amdgpu_irq.c
+ :internal:
+
+IP Blocks
+=========
+
+.. kernel-doc:: drivers/gpu/drm/amd/include/amd_shared.h
+ :doc: IP Blocks
+
+.. kernel-doc:: drivers/gpu/drm/amd/include/amd_shared.h
+ :identifiers: amd_ip_block_type amd_ip_funcs