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Roger Quadros 4c8566a12f net: ti: icssm-prueth: Add helper functions to configure and maintain FDB
Introduce helper functions to configure and maintain Forwarding
Database (FDB) tables to aid with the switch mode feature for PRU-ICSS
ports. The PRU-ICSS FDB is maintained such that it is always in sync with
the Linux bridge driver FDB.

The FDB is used by the driver to determine whether to flood a packet,
received from the user plane, to both ports or direct it to a specific port
using the flags in the FDB table entry.

The FDB is implemented in two main components: the Index table and the
MAC Address table. Adding, deleting, and maintaining entries are handled
by the PRUETH driver. There are two types of entries:

Dynamic: created from the received packets and are subject to aging.
Static: created by the user and these entries never age out.

8-bit hash value obtained using the source MAC address is used to identify
the index to the Index/Hash table. A bucket-based approach is used to
collate source MAC addresses with the same hash value. The Index/Hash table
holds the bucket index (16-bit value) and the number of entries in the
bucket with the same hash value (16-bit value). This table can hold up to
256 entries, with each entry consuming 4 bytes of memory. The bucket index
value points to the MAC address table indicating the start of MAC addresses
having the same hash values.

Each entry in the MAC Address table consists of:
1. 6 bytes of the MAC address,
2. 2-byte aging time, and
3. 1-byte each for port information and flags respectively.

When a new entry is added to the FDB, the hash value is calculated using an
XOR operation on the 6-byte MAC address. The result is used as an index
into the Hash/Index table to check if any entries exist. If no entries are
present, the first available empty slot in the MAC Address table is
allocated to insert this MAC address. If entries with the same hash value
are already present, the new MAC address entry is added to the MAC Address
table in such a way that it ensures all entries are grouped together and
sorted in ascending MAC address order. This approach helps efficiently
manage FDB entries.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Basharath Hussain Khaja <basharath@couthit.com>
Signed-off-by: Parvathi Pudi <parvathi@couthit.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260130124559.1182780-2-parvathi@couthit.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-02-04 18:12:00 -08:00
arch Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2026-01-29 17:28:54 -08:00
block block-6.19-20260122 2026-01-23 12:53:56 -08:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto crypto: authencesn - reject too-short AAD (assoclen<8) to match ESP/ESN spec 2026-01-20 14:38:48 +08:00
Documentation tcp: accecn: detect loss ACK w/ AccECN option and add TCP_ACCECN_OPTION_PERSIST 2026-02-03 15:13:25 +01:00
drivers net: ti: icssm-prueth: Add helper functions to configure and maintain FDB 2026-02-04 18:12:00 -08:00
fs for-6.19-rc7-tag 2026-01-29 09:07:17 -08:00
include net: usb: introduce usbnet_mii_ioctl helper function 2026-02-03 19:41:19 -08:00
init Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
io_uring io_uring-6.19-20260122 2026-01-23 12:51:00 -08:00
ipc Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
kernel tracing fixes for v6.19: 2026-01-24 17:18:57 -08:00
lib lib/crypto: sha1: Remove low-level functions from API 2026-01-27 15:47:41 -08:00
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 slab fix for 6.19-rc7 2026-01-21 09:19:15 -08:00
net net: bridge: use sysfs_emit instead of sprintf 2026-02-03 19:19:42 -08:00
rust Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2026-01-29 17:28:54 -08:00
samples samples/ftrace: Adjust LoongArch register restore order in direct calls 2025-12-31 15:19:25 +08:00
scripts tracing fixes for v6.19: 2026-01-24 17:18:57 -08:00
security keys/trusted_keys: fix handle passed to tpm_buf_append_name during unseal 2026-01-25 19:03:45 +02:00
sound ALSA: hda/realtek: ALC269 fixup for Lenovo Yoga Book 9i 13IRU8 audio 2026-01-22 13:33:41 +01:00
tools selftests/net: packetdrill: add TCP Accurate ECN cases 2026-02-03 15:13:25 +01:00
usr initramfs: add gen_init_cpio to hostprogs unconditionally 2025-11-26 21:55:40 +01:00
virt KVM fixes for 6.19-rc1 2025-12-18 18:38:45 +01:00
.clang-format s390/pci: Fix cyclic dead-lock in zpci_zdev_put() and zpci_scan_devices() 2025-12-14 11:03:58 +01:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: remove Alyssa Rosenzweig 2025-09-18 21:17:31 +02:00
.gitattributes
.gitignore rust: kbuild: add proc macro library support 2025-11-24 17:15:36 +01:00
.mailmap soc: fixes for 6.19, part 2 2026-01-21 09:34:45 -08:00
.pylintrc docs: Move the python libraries to tools/lib/python 2025-11-18 09:22:40 -07:00
.rustfmt.toml
COPYING
CREDITS net: ethernet: neterion: s2io: remove unused driver 2026-01-28 20:08:07 -08:00
Kbuild sched: Make migrate_{en,dis}able() inline 2025-09-25 09:57:16 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS dt-bindings: ptp: Add amazon,vmclock 2026-02-02 18:06:00 -08:00
Makefile Linux 6.19-rc7 2026-01-25 14:11:24 -08:00
README README: restructure with role-based documentation and guidelines 2025-11-29 08:40:33 -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


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



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