Patent ID: 6578102
Filing Date: 2003-06-10
Classification: G06F

Abstract:
In a PCI bus system for transferring data in the form of data streams comprising a plurality of contiguous blocks, said PCI bus system having a plurality of PCI busses, at least one PCI data destination coupled to a first of said plurality of PCI busses, at least one PCI data source coupled to a second of said plurality of PCI busses, and a prefetch buffer for storing said blocks of said data prefetched from said PCI data source associated as one of said data streams in response to a read command, said blocks of said data stream stored at said prefetch buffer for transfer to said data destination, said contiguous blocks of data capable of being grouped into major blocks comprising a fixed plurality of said contiguous blocks, a method for tracking and controlling said prefetching of said blocks of said data stream stored at said prefetch buffer, comprising the steps of:initializing a first count representing the number of said blocks of data comprising up to a major block of said data, and no more than the total number of said blocks of said data stream; setting a second count representing the total number of said blocks of said data stream to be prefetched and stored in said prefetch buffer, less said initialized number of blocks of said first count; upon prefetching and storing each said block of data at said prefetch buffer, decrementing said first count by a number representing said block of data; and upon said first count decrementing step decrementing to zero, stopping said prefetch and allowing completion of said transfer of said prefetched stored data to said data destination, whereby said second count represents the next remaining number of said blocks to be prefetched, stored and transferred.