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Paolo Abeni 73366893d1 Merge branch 'add-preliminary-netc-switch-support-for-i-mx94'
Wei Fang says:

====================
Add preliminary NETC switch support for i.MX94

i.MX94 NETC (v4.3) integrates 802.1Q Ethernet switch functionality, the
switch provides advanced QoS with 8 traffic classes and a full range of
TSN standards capabilities. It has 3 user ports and 1 CPU port, and the
CPU port is connected to an internal ENETC through the pseduo link, so
instead of a back-to-back MAC, the lightweight "pseudo MAC" is used at
both ends of the pseudo link to transfer Ethernet frames. The pseudo
link provides a zero-copy interface (no serialization delay) and lower
power (less logic and memory).

Like most Ethernet switches, the NETC switch also supports a proprietary
switch tag, is used to carry in-band metadata information about frames.
This in-band metadata information can include the source port from which
the frame was received, what was the reason why this frame got forwarded
to the entity, and for the entity to indicate the precise destination
port of a frame. The NETC switch tag is added to frames after the source
MAC address. There are three types of switch tags, and each type has 1
to 4 subtypes, more details are as follows.

Forward switch tag (Type = 0): Represents forwarded frames.
  - SubType = 0 - Normal frame processing.

To_Port switch tag (Type = 1): Represents frames that are to be sent to
a specific switch port.
  - SubType = 0. No request to perform timestamping.
  - SubType = 1. Request to perform one-step timestamping.
  - SubType = 2. Request to perform two-step timestamping.
  - SubType = 3. Request to perform both one-step timestamping and
    two-step timestamping.

To_Host switch tag (Type = 2): Represents frames redirected or copied to
the switch management port.
  - SubType = 0. Received frames redirected or copied to the switch
     management port.
  - SubType = 1. Received frames redirected or copied to the switch
    management port with captured timestamp at the switch port where
    the frame was received.
  - SubType = 2. Transmit timestamp response (two-step timestamping).

Currently, this patch set supports Forward tag, SubType 0 of To_Port tag
and SubType 0 of To_Host tag. More tags will be supported in the future.

In addition, the switch supports NETC Table Management Protocol (NTMP),
some switch functionality is controlled using control messages sent to
the hardware using BD ring interface with 32B descriptors similar to the
packet Transmit BD ring used on ENETC. This interface is referred to as
the command BD ring. This is used to configure functionality where the
underlying resources may be shared between different entities or being
too large to configure using direct registers.

For this patch set, we have supported the following tables through the
command BD ring interface.

FDB Table: It contains forwarding and/or filtering information about MAC
addresses. The FDB table is used for MAC learning lookups and MAC
forwarding lookups.

VLAN Filter Table: It contains configuration and control information for
each VLAN configured on the switch.

Buffer Pool Table: It contains buffer pool configuration and operational
information. Each entry corresponds to a buffer pool. Currently, we use
this table to implement flow control feature on each port.

Ingress Port Filter Table: It contains a set of filters each capable of
classifying incoming traffic using a mix of L2, L3, and L4 parsed and
arbitrary field data. We use this table to implement host flood support
to the switch port.

The switch also supports other tables, and we will add more advanced
features through them in the future.
====================

Link: https://patch.msgid.link/20260518082506.1318236-1-wei.fang@nxp.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-05-21 13:04:45 +02:00
arch Arm: 2026-05-13 11:53:51 -07:00
block block: only read from sqe on initial invocation of blkdev_uring_cmd() 2026-05-05 01:37:12 -06:00
certs Clang build fixes for 7.1 2026-04-24 09:29:51 -07:00
crypto This push contains the following changes: 2026-05-02 12:31:43 -07:00
Documentation dt-bindings: net: dsa: add NETC switch 2026-05-21 13:04:41 +02:00
drivers net: dsa: netc: add support for ethtool private statistics 2026-05-21 13:04:42 +02:00
fs fsverity fix for v7.1-rc3 2026-05-09 11:47:39 -07:00
include net: dsa: netc: add support for the standardized counters 2026-05-21 13:04:42 +02:00
init memblock: updates for 7.0-rc1 2026-04-18 11:29:14 -07:00
io_uring io_uring-7.1-20260508 2026-05-08 13:12:48 -07:00
ipc Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
kernel audit/stable-7.1 PR 20260513 2026-05-14 08:53:24 -07:00
lib Probes fixes for v7.1-rc3 2026-05-12 10:18:02 -07:00
LICENSES LICENSES: Add modern form of the LGPL-2.1 tags to the usage guide section 2025-10-22 07:58:19 +02:00
mm liveupdate fixes for v7.1-rc4 2026-05-13 08:24:50 -07:00
net net: dsa: add NETC switch tag support 2026-05-21 13:04:42 +02:00
rust Rust fixes for v7.1 2026-05-09 11:24:02 -07:00
samples soc: drivers for 7.1 2026-04-16 20:34:34 -07:00
scripts First round of Kbuild fixes for 7.1 2026-04-25 17:04:15 -07:00
security selinux: shrink critical section in sel_write_load() 2026-05-05 16:02:28 -04:00
sound ASoC: Fixes for v7.1 2026-05-06 16:10:00 +02:00
tools selftests: rds: Add ROCE support to run.sh 2026-05-20 17:03:03 -07:00
usr kbuild: uapi: also test UAPI headers against C++ compilers 2026-03-25 13:24:42 +01:00
virt KVM: Reject wrapped offset in kvm_reset_dirty_gfn() 2026-05-12 22:16:16 +02:00
.clang-format Devicetree updates for v7.0: 2026-02-11 18:27:08 -08:00
.clippy.toml rust: bump Clippy's MSRV and clean incompatible_msrv allows 2026-04-07 09:51:39 +02:00
.cocciconfig
.editorconfig editorconfig: add rst extension 2026-01-26 19:07:09 -08:00
.get_maintainer.ignore .get_maintainer.ignore: add myself 2026-04-02 16:48:25 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: rust: provide an option to inline C helpers into Rust 2026-03-30 02:03:52 +02:00
.mailmap MAINTAINERS: Update mail for Peter Rosin 2026-05-04 21:02:58 +02:00
.pylintrc docs: Move the python libraries to tools/lib/python 2025-11-18 09:22:40 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS Delete some obsolete networking code 2026-04-24 09:41:58 -07:00
Kbuild checksyscalls: move instance functionality into generic code 2026-04-05 09:21:32 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS net: dsa: netc: introduce NXP NETC switch driver for i.MX94 2026-05-21 13:04:42 +02:00
Makefile Linux 7.1-rc3 2026-05-10 14:08:09 -07:00
README docs: add AI Coding Assistants documentation 2026-01-06 14:55:06 -07:00

Linux kernel
============

The Linux kernel is the core of any Linux operating system. It manages hardware,
system resources, and provides the fundamental services for all other software.

Quick Start
-----------

* Report a bug: See Documentation/admin-guide/reporting-issues.rst
* Get the latest kernel: https://kernel.org
* Build the kernel: See Documentation/admin-guide/quickly-build-trimmed-linux.rst
* Join the community: https://lore.kernel.org/

Essential Documentation
-----------------------

All users should be familiar with:

* Building requirements: Documentation/process/changes.rst
* Code of Conduct: Documentation/process/code-of-conduct.rst
* License: See COPYING

Documentation can be built with make htmldocs or viewed online at:
https://www.kernel.org/doc/html/latest/


Who Are You?
============

Find your role below:

* New Kernel Developer - Getting started with kernel development
* Academic Researcher - Studying kernel internals and architecture
* Security Expert - Hardening and vulnerability analysis
* Backport/Maintenance Engineer - Maintaining stable kernels
* System Administrator - Configuring and troubleshooting
* Maintainer - Leading subsystems and reviewing patches
* Hardware Vendor - Writing drivers for new hardware
* Distribution Maintainer - Packaging kernels for distros
* AI Coding Assistant - LLMs and AI-powered development tools


For Specific Users
==================

New Kernel Developer
--------------------

Welcome! Start your kernel development journey here:

* Getting Started: Documentation/process/development-process.rst
* Your First Patch: Documentation/process/submitting-patches.rst
* Coding Style: Documentation/process/coding-style.rst
* Build System: Documentation/kbuild/index.rst
* Development Tools: Documentation/dev-tools/index.rst
* Kernel Hacking Guide: Documentation/kernel-hacking/hacking.rst
* Core APIs: Documentation/core-api/index.rst

Academic Researcher
-------------------

Explore the kernel's architecture and internals:

* Researcher Guidelines: Documentation/process/researcher-guidelines.rst
* Memory Management: Documentation/mm/index.rst
* Scheduler: Documentation/scheduler/index.rst
* Networking Stack: Documentation/networking/index.rst
* Filesystems: Documentation/filesystems/index.rst
* RCU (Read-Copy Update): Documentation/RCU/index.rst
* Locking Primitives: Documentation/locking/index.rst
* Power Management: Documentation/power/index.rst

Security Expert
---------------

Security documentation and hardening guides:

* Security Documentation: Documentation/security/index.rst
* LSM Development: Documentation/security/lsm-development.rst
* Self Protection: Documentation/security/self-protection.rst
* Reporting Vulnerabilities: Documentation/process/security-bugs.rst
* CVE Procedures: Documentation/process/cve.rst
* Embargoed Hardware Issues: Documentation/process/embargoed-hardware-issues.rst
* Security Features: Documentation/userspace-api/seccomp_filter.rst

Backport/Maintenance Engineer
-----------------------------

Maintain and stabilize kernel versions:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* Backporting Guide: Documentation/process/backporting.rst
* Applying Patches: Documentation/process/applying-patches.rst
* Subsystem Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git for Maintainers: Documentation/maintainer/configure-git.rst

System Administrator
--------------------

Configure, tune, and troubleshoot Linux systems:

* Admin Guide: Documentation/admin-guide/index.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Sysctl Tuning: Documentation/admin-guide/sysctl/index.rst
* Tracing/Debugging: Documentation/trace/index.rst
* Performance Security: Documentation/admin-guide/perf-security.rst
* Hardware Monitoring: Documentation/hwmon/index.rst

Maintainer
----------

Lead kernel subsystems and manage contributions:

* Maintainer Handbook: Documentation/maintainer/index.rst
* Pull Requests: Documentation/maintainer/pull-requests.rst
* Managing Patches: Documentation/maintainer/modifying-patches.rst
* Rebasing and Merging: Documentation/maintainer/rebasing-and-merging.rst
* Development Process: Documentation/process/maintainer-handbooks.rst
* Maintainer Entry Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git Configuration: Documentation/maintainer/configure-git.rst

Hardware Vendor
---------------

Write drivers and support new hardware:

* Driver API Guide: Documentation/driver-api/index.rst
* Driver Model: Documentation/driver-api/driver-model/driver.rst
* Device Drivers: Documentation/driver-api/infrastructure.rst
* Bus Types: Documentation/driver-api/driver-model/bus.rst
* Device Tree Bindings: Documentation/devicetree/bindings/
* Power Management: Documentation/driver-api/pm/index.rst
* DMA API: Documentation/core-api/dma-api.rst

Distribution Maintainer
-----------------------

Package and distribute the kernel:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* ABI Documentation: Documentation/ABI/README
* Kernel Configuration: Documentation/kbuild/kconfig.rst
* Module Signing: Documentation/admin-guide/module-signing.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Tainted Kernels: Documentation/admin-guide/tainted-kernels.rst

AI Coding Assistant
-------------------

CRITICAL: If you are an LLM or AI-powered coding assistant, you MUST read and
follow the AI coding assistants documentation before contributing to the Linux
kernel:

* Documentation/process/coding-assistants.rst

This documentation contains essential requirements about licensing, attribution,
and the Developer Certificate of Origin that all AI tools must comply with.


Communication and Support
=========================

* Mailing Lists: https://lore.kernel.org/
* IRC: #kernelnewbies on irc.oftc.net
* Bugzilla: https://bugzilla.kernel.org/
* MAINTAINERS file: Lists subsystem maintainers and mailing lists
* Email Clients: Documentation/process/email-clients.rst