Negotiating a transmit wake time

Patent metadata

Field	Value
Publication number	US-2016378159-A1
Application number	US-201615236463-A
Country	US
Kind code	A1
Filing date	Aug 14, 2016
Priority date	Mar 17, 2009
Publication date	Dec 29, 2016
Grant date	—

Abstract

Includes receiving, from a link partner, a message specifying a link partner receive wake time and resolving to the lesser of the received link partner receive wake time and a local transmit wake time.

First claim

What is claimed is:

1 . A method, comprising:
receiving, from a link partner, a message specifying a link partner receive wake time; resolving to a transmit wake time based on the received link partner receive wake time and a local transmit wake time; receiving a request to transmit data to the link partner; and after sending a wake signal to the link partner, waiting for at least the transmit wake time to delay transmitting data to the link partner.

2 . The method of claim 1 , further comprising:
determining the local transmit wake time based on transmit buffer space available for transmitting data to the remote link partner; and wherein waiting for at least the transmit wake time to delay transmitting data to the link partner includes buffering data destined for the remote link buffer.

3 . The method of claim 1 ,
the message further specifies a link partner transmit wake time; and determining a local receive wake time based, at least in part, on a wake time of a PHY.

4 . The method of claim 3 , determining the local receive wake time comprises determining based on a wake requirement of a one of a set of multiple power reduction modes.

5 . The method of claim 1 , comprising:
transmitting a frame to the link partner, the frame including the local transmit wake time and a local receive wake time.

6 . The method of claim 1 , the message comprises a link layer discovery protocol frame.

7 . The method of claim 1 , comprising:
periodically receiving, from the link partner, refresh signals during a low power mode of the link partner; and performing timing recovery and coefficient updating responsive to each received refresh signal.

8 . The method of claim 2 , receiving the message, resolving to the transmit wake time, and buffering data comprises receiving, resolving, and buffering at a network interface controller, the network interface controller including a PHY, a media access controller, and a direct memory access (DMA) engine.

9 . The method of claim 1 , the message further comprises a wake time for a PHY.

10 . A system, comprising:
a network interface controller, the network interface controller including:
a PHY;
a media access controller;
a direct memory access engine; and
circuitry to:
receive, from a link partner, a message specifying a link partner receive wake time;
resolve to a transmit wake time based on the received link partner receive wake time and a local transmit wake time;
receive a request to transmit data to the link partner;
send a wake signal to the link partner; and
wait for at least the transmit wake time to cause a delay to transmission of data to the link partner.

11 . The system of claim 1 , further comprising the logic to:
determine the local transmit wake time based on transmit buffer space available to transmit data to the remote link partner; and wherein to wait for at least the transmit wake time to cause a delay to transmission of data to the link partner includes causing data destined for the remote link buffer to be buffered in the transmit buffer.

12 . The system of claim 10 , further comprising the circuitry to store a local transmit wake time.

13 . The system of claim 10 , further comprising the circuitry to store a PHY transmit wake value for the PHY.

14 . The system of claim 13 , comprising:
the message to further indicate a link partner transmit wake time; and the circuitry to determine a local receive wake time based, at least in part, on the PHY transmit wake value.

15 . The system of claim 14 , comprising:
the circuitry to determine the local receive wake time based on requirements of one of a set multiple power reduction modes.

16 . The system of claim 10 , further comprising the circuitry to transmit a message to the link partner, the message including a local transmit wake time and the local receive wake time.

17 . The system of claim 10 , the message comprises a link layer discovery protocol frame.

18 . The system of claim 10 , further comprising the circuitry to:
periodically receive, from the link partner, refresh signals during a low power mode of the link partner; and perform timing recovery and coefficient updating responsive to each received refresh signal.

19 . The system of claim 10 , further comprising:
memory; a processor; and a power management unit, the power management unit to indicate to the network interface controller a wake period associated with a selected one of multiple power reduction modes.

20 . The system of claim 18 , the power management unit enters a selected one of multiple power reduction modes based on the transmit wake time.

21 . A method, comprising:
receiving, from a link partner, a message specifying a link partner transmit wake time; resolving to a transmit wake time based on the received link partner transmit wake time and a local receive wake time; after receiving a sleep message from the link partner, entering a system power saving mode based, at least in part, on the resolved receive wake time; after receiving a wake signal from the link partner, exiting the system power saving mode; and receiving data from the link partner no sooner than the resolved receive wake time.

22 . The method of claim 21 , further comprising:
notifying a system power management unit of the resolved transmit wake time.

23 . The method of claim 22 , notifying the system power management unit comprises notifying after receiving the sleep message.

24 . The method of claim 10 , further comprising:
periodically receiving, from the link partner, refresh signals while in the system power saving mode; and performing timing recovery and coefficient updating responsive to each received refresh signal.

Assignees

• Intel Corp

Inventors

• Wertheimer Aviad
• Hays Robert

Classifications

• G06F1/3203 Primary

  Power management, i.e. event-based initiation of a power-saving mode · CPC title

• G06F1/3209

  Monitoring remote activity, e.g. over telephone lines or network connections · CPC title

• Y02D30/00

  Reducing energy consumption in communication networks · CPC title