Inter-processor communication channel including power-down functionality

摘要

Apparatuses and methods are disclosed for implementing an inter-processor communication channel including power-down functionality. In one embodiment, the apparatus may comprise a first integrated circuit (IC), a second IC coupled to the first IC via a communication interface, wherein the first IC is in one or more low power states and unable to monitor the communication interface. The apparatus may further comprise an inter-processor communication (IPC) channel coupled between the first and second ICs, wherein the IPC channel is separate from the communication interface and wherein the second IC generates at least one advisory signal to the first IC via the IPC channel.

主权项

1. A method of managing power by a communications circuit, the method comprising:
monitoring at least one transmission signal on a communication interface within the communications circuit, wherein the communications interface is coupled to an external device; monitoring at least one receive signal on the communication interface; determining if data is present on the communication interface on the at least one transmission signal and on the at least one receive signal, wherein said determining is performed by delaying a synchronization signal conveyed between the communications interface and the external device and checking for a presence of at least one transmission signal or at least one receive signal subsequent to said delaying; resetting a count responsive to determining that data is present on the at least one transmission signal or the at least one receive signal; incrementing a count responsive to determining that both the at least one transmission signal and the at least one receive signal are not present; sending a command to an integrated circuit coupled to the communications circuit to enter a low power state responsive to the determination that the count has reach a pre-determined value; and scaling a clock signal down to a lower frequency responsive to the determination that the count has reached a pre-determined value.