EthSwt

The opening post of the EthSwt tutorial series: the module's state machine, the configuration classes as defined by the SWS, and where EthSwt sits between EthIf and the switch ports in the AUTOSAR stack.

The concrete EthSwt function calls: the init sequence with its background task, port modes, link state, and what to watch for when EthSwt interacts with EthTrcv on switch ports.

The real ARXML container structure of EthSwt: EthSwtPort, EthSwtPortIngress and the actual VLAN parameters — including a complete configuration example.

Toggling VLANs at runtime, EthSwt's surprisingly powerful port-mirror configuration, MAC learning modes, and diagnostics via MIB counters.

The three hardware variants for switch/PHY arrangements defined by the AUTOSAR SWS, the forwarding engine, and typical switch chips in practice.

Host-side interfaces (RGMII/SGMII) to the switch, internal forwarding paths, PCB and power aspects of multi-port chips, and the path a frame takes through the switch.

Typical failure patterns during EthSwt chip bring-up — from a port that won't come up to a host interface that doesn't respond — with concrete debugging paths.

How EthSwt accesses a switch chip via SPI: the real EthSwtSpi/EthSwtSpiSequence configuration and the generic register-access APIs that abstract MII and SPI alike.

The real EthSwt_ReadMmd/WriteMmd API for Clause 45 register access over the SMI — including emulation via Clause 22 operations if the hardware doesn't natively support Clause 45.

Vendor mechanisms for switch configuration via special Ethernet frames — and the important distinction from EthSwt_SetMgmtInfo, the real AUTOSAR mechanism for port-specific frame handling.

How EthSwt identifies Ethernet frames as streams using AND-linked filter rules, and which filter actions (drop, block-source, VLAN modification, egress redirection) can follow.

How EthSwt supplies the AUTOSAR Firewall module with StreamHandleIdentifiers and bucket statistics so it can raise security events to the IdsM — including the DRAFT-status APIs behind this functionality.

Cascaded egress schedulers, credit-based shaping and enhanced transmission selection, plus IEEE 802.1Q frame preemption — the core AUTOSAR mechanisms for deterministic Ethernet in the switch.

How EthSwt manages secure channels and secure associations per switch port, with bypass lists for management traffic and a shared MKA key infrastructure with EthTrcv.

How EthSwt provides port-specific hardware timestamps for EthTSyn, and how cascaded switches synchronize their internal clocks over uplink ports to avoid separate path-delay measurement.

The two MAC learning modes defined by IEEE 802.1Q and AUTOSAR — SVL and IVL — the start-up learning phase, and the two-phase query pattern of EthSwt_GetArlTable.

The surprising fact-check finding: most of EthSwt's port diagnostic APIs are pure forwarders to the referenced EthTrcv instance, not switch-native functionality.

What's actually inside a switch chip's silicon? Shared-memory vs. crossbar fabric, the lookup engine, buffer architecture, egress queues in hardware, and the embedded management core.

Real switch stacking distinguished from the cascading already covered: shared FDB/management plane, dedicated stacking links, and what this means for EthSwt from an AUTOSAR perspective.

EthSwt explained: when an AUTOSAR Ethernet ECU needs a switch driver instead of a plain EthTrcv, what the API looks like, and how VLANs, mirroring, and spanning tree are configured.