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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
+
+.. include:: <isonum.txt>
+
+Qualcomm Camera Subsystem driver
+================================
+
+Introduction
+------------
+
+This file documents the Qualcomm Camera Subsystem driver located under
+drivers/media/platform/qcom/camss.
+
+The current version of the driver supports the Camera Subsystem found on
+Qualcomm MSM8916/APQ8016 and MSM8996/APQ8096 processors.
+
+The driver implements V4L2, Media controller and V4L2 subdev interfaces.
+Camera sensor using V4L2 subdev interface in the kernel is supported.
+
+The driver is implemented using as a reference the Qualcomm Camera Subsystem
+driver for Android as found in Code Aurora [#f1]_ [#f2]_.
+
+
+Qualcomm Camera Subsystem hardware
+----------------------------------
+
+The Camera Subsystem hardware found on 8x16 / 8x96 processors and supported by
+the driver consists of:
+
+- 2 / 3 CSIPHY modules. They handle the Physical layer of the CSI2 receivers.
+ A separate camera sensor can be connected to each of the CSIPHY module;
+- 2 / 4 CSID (CSI Decoder) modules. They handle the Protocol and Application
+ layer of the CSI2 receivers. A CSID can decode data stream from any of the
+ CSIPHY. Each CSID also contains a TG (Test Generator) block which can generate
+ artificial input data for test purposes;
+- ISPIF (ISP Interface) module. Handles the routing of the data streams from
+ the CSIDs to the inputs of the VFE;
+- 1 / 2 VFE (Video Front End) module(s). Contain a pipeline of image processing
+ hardware blocks. The VFE has different input interfaces. The PIX (Pixel) input
+ interface feeds the input data to the image processing pipeline. The image
+ processing pipeline contains also a scale and crop module at the end. Three
+ RDI (Raw Dump Interface) input interfaces bypass the image processing
+ pipeline. The VFE also contains the AXI bus interface which writes the output
+ data to memory.
+
+
+Supported functionality
+-----------------------
+
+The current version of the driver supports:
+
+- Input from camera sensor via CSIPHY;
+- Generation of test input data by the TG in CSID;
+- RDI interface of VFE
+
+ - Raw dump of the input data to memory.
+
+ Supported formats:
+
+ - YUYV/UYVY/YVYU/VYUY (packed YUV 4:2:2 - V4L2_PIX_FMT_YUYV /
+ V4L2_PIX_FMT_UYVY / V4L2_PIX_FMT_YVYU / V4L2_PIX_FMT_VYUY);
+ - MIPI RAW8 (8bit Bayer RAW - V4L2_PIX_FMT_SRGGB8 /
+ V4L2_PIX_FMT_SGRBG8 / V4L2_PIX_FMT_SGBRG8 / V4L2_PIX_FMT_SBGGR8);
+ - MIPI RAW10 (10bit packed Bayer RAW - V4L2_PIX_FMT_SBGGR10P /
+ V4L2_PIX_FMT_SGBRG10P / V4L2_PIX_FMT_SGRBG10P / V4L2_PIX_FMT_SRGGB10P /
+ V4L2_PIX_FMT_Y10P);
+ - MIPI RAW12 (12bit packed Bayer RAW - V4L2_PIX_FMT_SRGGB12P /
+ V4L2_PIX_FMT_SGBRG12P / V4L2_PIX_FMT_SGRBG12P / V4L2_PIX_FMT_SRGGB12P).
+ - (8x96 only) MIPI RAW14 (14bit packed Bayer RAW - V4L2_PIX_FMT_SRGGB14P /
+ V4L2_PIX_FMT_SGBRG14P / V4L2_PIX_FMT_SGRBG14P / V4L2_PIX_FMT_SRGGB14P).
+
+ - (8x96 only) Format conversion of the input data.
+
+ Supported input formats:
+
+ - MIPI RAW10 (10bit packed Bayer RAW - V4L2_PIX_FMT_SBGGR10P / V4L2_PIX_FMT_Y10P).
+
+ Supported output formats:
+
+ - Plain16 RAW10 (10bit unpacked Bayer RAW - V4L2_PIX_FMT_SBGGR10 / V4L2_PIX_FMT_Y10).
+
+- PIX interface of VFE
+
+ - Format conversion of the input data.
+
+ Supported input formats:
+
+ - YUYV/UYVY/YVYU/VYUY (packed YUV 4:2:2 - V4L2_PIX_FMT_YUYV /
+ V4L2_PIX_FMT_UYVY / V4L2_PIX_FMT_YVYU / V4L2_PIX_FMT_VYUY).
+
+ Supported output formats:
+
+ - NV12/NV21 (two plane YUV 4:2:0 - V4L2_PIX_FMT_NV12 / V4L2_PIX_FMT_NV21);
+ - NV16/NV61 (two plane YUV 4:2:2 - V4L2_PIX_FMT_NV16 / V4L2_PIX_FMT_NV61).
+ - (8x96 only) YUYV/UYVY/YVYU/VYUY (packed YUV 4:2:2 - V4L2_PIX_FMT_YUYV /
+ V4L2_PIX_FMT_UYVY / V4L2_PIX_FMT_YVYU / V4L2_PIX_FMT_VYUY).
+
+ - Scaling support. Configuration of the VFE Encoder Scale module
+ for downscalling with ratio up to 16x.
+
+ - Cropping support. Configuration of the VFE Encoder Crop module.
+
+- Concurrent and independent usage of two (8x96: three) data inputs -
+ could be camera sensors and/or TG.
+
+
+Driver Architecture and Design
+------------------------------
+
+The driver implements the V4L2 subdev interface. With the goal to model the
+hardware links between the modules and to expose a clean, logical and usable
+interface, the driver is split into V4L2 sub-devices as follows (8x16 / 8x96):
+
+- 2 / 3 CSIPHY sub-devices - each CSIPHY is represented by a single sub-device;
+- 2 / 4 CSID sub-devices - each CSID is represented by a single sub-device;
+- 2 / 4 ISPIF sub-devices - ISPIF is represented by a number of sub-devices
+ equal to the number of CSID sub-devices;
+- 4 / 8 VFE sub-devices - VFE is represented by a number of sub-devices equal to
+ the number of the input interfaces (3 RDI and 1 PIX for each VFE).
+
+The considerations to split the driver in this particular way are as follows:
+
+- representing CSIPHY and CSID modules by a separate sub-device for each module
+ allows to model the hardware links between these modules;
+- representing VFE by a separate sub-devices for each input interface allows
+ to use the input interfaces concurrently and independently as this is
+ supported by the hardware;
+- representing ISPIF by a number of sub-devices equal to the number of CSID
+ sub-devices allows to create linear media controller pipelines when using two
+ cameras simultaneously. This avoids branches in the pipelines which otherwise
+ will require a) userspace and b) media framework (e.g. power on/off
+ operations) to make assumptions about the data flow from a sink pad to a
+ source pad on a single media entity.
+
+Each VFE sub-device is linked to a separate video device node.
+
+The media controller pipeline graph is as follows (with connected two / three
+OV5645 camera sensors):
+
+.. _qcom_camss_graph:
+
+.. kernel-figure:: qcom_camss_graph.dot
+ :alt: qcom_camss_graph.dot
+ :align: center
+
+ Media pipeline graph 8x16
+
+.. kernel-figure:: qcom_camss_8x96_graph.dot
+ :alt: qcom_camss_8x96_graph.dot
+ :align: center
+
+ Media pipeline graph 8x96
+
+
+Implementation
+--------------
+
+Runtime configuration of the hardware (updating settings while streaming) is
+not required to implement the currently supported functionality. The complete
+configuration on each hardware module is applied on STREAMON ioctl based on
+the current active media links, formats and controls set.
+
+The output size of the scaler module in the VFE is configured with the actual
+compose selection rectangle on the sink pad of the 'msm_vfe0_pix' entity.
+
+The crop output area of the crop module in the VFE is configured with the actual
+crop selection rectangle on the source pad of the 'msm_vfe0_pix' entity.
+
+
+Documentation
+-------------
+
+APQ8016 Specification:
+https://developer.qualcomm.com/download/sd410/snapdragon-410-processor-device-specification.pdf
+Referenced 2016-11-24.
+
+APQ8096 Specification:
+https://developer.qualcomm.com/download/sd820e/qualcomm-snapdragon-820e-processor-apq8096sge-device-specification.pdf
+Referenced 2018-06-22.
+
+References
+----------
+
+.. [#f1] https://source.codeaurora.org/quic/la/kernel/msm-3.10/
+.. [#f2] https://source.codeaurora.org/quic/la/kernel/msm-3.18/