
Priority-based Flow Control responder/originator — 8-priority, lockstep-safe. It is delivered as a licensable soft-IP block engineered as an ASIL-B Safety Element out of Context — not just RTL, but the complete functional-safety work package needed to carry it into an ISO 26262 program:
A synthesizable Ethernet Priority-based Flow Control (PFC) link-endpoint controller soft-IP — a standalone digital IP that taps an RX byte-stream to detect and act on incoming PFC control frames, and can generate its own PFC frames on a TX byte-stream, matching this catalog’s “digital-only, connects to an external MAC/PHY” convention already used for dp_link/csi2_rx.
IEEE 802.1Qbz / 802.3x Annex 31D Priority-based Flow Control (public shape only — clean-room reduced-scope approximation, not a verified implementation of the licensed specification)
ASIL-B (SEooC) · SPFM 90.20% · LFM 88.80% · PASS
ISO 26262:2018 · FMEDA available · Safety Manual included
| Offset | Register | Description |
|---|---|---|
0x00 | CTRL | RW [0]=EN [1]=SEND_PFC (self-clearing command trigger) |
0x04 | STATUS | RO/W1C [7:0]=PAUSE_ACTIVE mirror (RO) [8]=PROTO_ERR (W1C, mirrors err_code 3) [9]=TX_BUSY (RO) |
0x08 | ENABLE_VEC | RW [7:0] = priority-enable vector for the NEXT generated PFC frame |
0x0C..0x28 | QUANTA0..7 | RW [15:0] each, 4-byte stride = per-priority pause-quanta for the NEXT generated frame (8 registers) |
0x2C..0x48 | RXQ_RB0..7 | RO [15:0] each, 4-byte stride = CURRENT remaining RX countdown for priority N (8 registers, live diagnostic mirror) |
…1 more registers — see datasheet for the full table.
// Minimal instantiation
eth_pfc #(
.ADDR_W(6)
) u_eth_pfc (
.clk (clk),
.rst_n (rst_n),
// APB4
.p_paddr (paddr),
.p_psel (psel),
.p_penable (penable),
.p_pwrite (pwrite),
.p_pwdata (pwdata),
.p_prdata (prdata),
.p_pready (pready),
// Safety
.err_clear (1'b0),
.err_valid (err_valid),
.err_code (err_code)
);Configure via the CTRL register after reset to enable the IP and set operating parameters. Monitor err_valid / err_code for any safety faults reported by the built-in safety monitor.
Typically deployed in in-vehicle networks, industrial gateways, and sensor/actuator links where a bus controller has to carry its own safety argument.
Pricing, the per-IP FMEDA, safety manual, and RTL data room are shared under a mutual NDA.
Figures are pre-silicon engineering-grade estimates for a Safety Element out of Context (SEooC); final ASIL sign-off is the integrator’s, supported under NDA. FMEDA and Safety Manual available under NDA.
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