Input/output device including a host interface for processing function level reset requests and updating a timer value corresponding to a time until application hardware registers associated with the function level reset requests are available

Abstract

An I/O device includes a host interface configured to process function level reset (FLR) requests in a specified amount of time. The host interface includes a control unit and groups of configuration space registers, each group corresponding to a function. The host interface also includes application availability registers, each associated with a respective function, and which may indicate whether application hardware within the respective function is available for access by a corresponding application device driver. The I/O device also includes application hardware resources associated with a respective function. In response to receiving an FLR request of a particular function, the control unit may cause the associated application availability register to indicate that the application hardware within the particular function is not available to the driver. The control unit may reset the corresponding configuration space registers within a predetermined amount of time and reset the associated application hardware resources.