Shared write buffer in a peripheral interface and method of operating

摘要

A data processing system has a single configurable write buffer within a peripheral interface unit that is shared among multiple peripherals. Configuration registers are dynamically programmed to control criteria for determining whether control of a system bus will be released prior to completion of a write access to a peripheral. The criteria include which peripheral is being accessed, the particular bus master that is requesting the write request, and a mode of operation, such as supervisor or user write access modes. Write buffering may also be dynamically disabled for individual peripherals based on the state of a peripheral by using a hardware side band signal driven by the peripheral to override a static buffer write policy programmed in control registers.