Control of ethernet link-partner GPIO using OAM
An Ethernet Physical layer (PHY) device includes a PHY interface and PHY circuitry. The PHY interface is configured to connect to a physical link. The PHY circuitry is configured to generate layer-1 frames that carry data for transmission to a peer Ethernet PHY device, to insert among the layer-1 frames one or more management frames that are separate from the layer-1 frames and that are configured to control a General-Purpose Input-Output (GPIO) port associated with the peer Ethernet PHY device, to transmit the layer-1 frames and the inserted management frames, via the PHY interface, to the peer Ethernet PHY device over the physical link, for controlling one or more operations of the GPIO port associated with the peer Ethernet PHY device, and to receive, via the PHY interface, one or more verifications acknowledging that the one or more management frames were received successfully at the peer Ethernet PHY device.
1. An in-vehicle Ethernet communication system, comprising:
a first Ethernet Physical layer (PHY) device comprising (i) a first interface configured to connect to a first system controller and (ii) a first General-Purpose Input-Output (GPIO) port that is separate from the first interface, the first GPIO port configured to connect to a first safety controller; and
a second Ethernet PHY device comprising (i) a second interface configured to connect to a second system controller and (ii) a second GPIO port that is separate from the second interface, the second GPIO port configured to connect to a second safety controller,
the first and second Ethernet PHY devices being configured to:
transfer data between the first and second system controllers by (i) communicating with the first and second system controllers via the first and second interfaces and (ii) transmitting and receiving, over a physical Ethernet link between the first and second Ethernet PHY devices, layer-1 Ethernet frames that carry the data; and
transfer safety messages between the first and second safety controllers, over the same physical Ethernet link and independently of the first and second system controllers, by (i) communicating with the first and second safety controllers via the first and second GPIO ports, and (ii) transferring, over the physical Ethernet link, Ethernet Operations Administration and Maintenance (OAM) frames that are interleaved among the layer-1 Ethernet frames and that carry the safety messages.
2. The in-vehicle Ethernet communication system according to claim 1 , wherein the first Ethernet PHY device is configured to receive one or more of the Ethernet OAM frames from the first safety controller over the first GPIO port.
3. The in-vehicle Ethernet communication system according to claim 1 , wherein the first Ethernet PHY device is configured to receive one or more of the safety messages over the first GPIO port, and to compose at least one of the OAM frames using the one or more of the safety messages.
4. The in-vehicle Ethernet communication system according to claim 1 , wherein the first Ethernet PHY device is configured to reset the first safety controller via the first GPIO port in response to at least one of the Ethernet OAM frames.
5. The in-vehicle Ethernet communication system according to claim 1 , wherein the first Ethernet PHY device is configured to read a status of the first safety controller via the first GPIO port in response to at least one of the Ethernet OAM frames.
6. The in-vehicle Ethernet communication system according to claim 1 , wherein the first Ethernet PHY device is configured to send multiple bits of information to the first safety controller, by varying a logic value on the first GPIO port over time.
7. A method for communication in an in-vehicle Ethernet communication system that includes (i) a first Ethernet Physical layer (PHY) device comprising a first interface connected to a first system controller, and a first General-Purpose Input-Output (GPIO) port that is separate from the first interface, the first GPIO port connected to a first safety controller, and (ii) a second Ethernet PHY device comprising a second interface connected to a second system controller, and a second GPIO port that is separate from the second interface, the second GPIO port connected to a second safety controller, the method comprising:
transferring data between the first and second system controllers by (i) communicating with the first and second system controllers via the first and second interfaces and (ii) transmitting and receiving, over a physical Ethernet link between the first and second Ethernet PHY devices, layer-1 Ethernet frames that carry the data; and
transferring safety messages between the first and second safety controllers, over the same physical Ethernet link and independently of the first and second system controllers, by (i) communicating with the first and second safety controllers via the first and second GPIO ports, and (ii) transferring, over the physical Ethernet link, Ethernet Operations Administration and Maintenance (OAM) frames that are interleaved among the layer-1 Ethernet frames and that carry the safety messages.
8. The method for communication according to claim 7 , wherein transferring the safety messages comprises receiving one or more of the Ethernet OAM frames at the first Ethernet PHY device from the first safety controller over the first GPIO port.
9. The method for communication according to claim 7 , wherein transferring the safety messages comprises, in the first Ethernet PHY device, receiving one or more of the safety messages from the first safety controller over the first GPIO port, and composing at least one of the OAM frames using the one or more of the safety messages.
10. The method for communication according to claim 7 , further comprising resetting the first safety controller by the first Ethernet PHY device via the first GPIO port, in response to at least one of the Ethernet OAM frames.
11. The method for communication according to claim 7 , further comprising reading a status of the first safety controller by the first Ethernet PHY device via the first GPIO port, in response to at least one of the Ethernet OAM frames.
12. The method for communication according to claim 7 , wherein transferring the safety messages comprises sending multiple bits of information from the first Ethernet PHY device to the first safety controller, by varying a logic value on the first GPIO port over time.