Abstract: An embedded DRAM (eDRAM) having multi-use refresh cycles is described. In one embodiment, there is a multi-level cache memory system that comprises a pending write queue configured to receive pending prefetch operations from at least one of the levels of cache. A prefetch queue is configured to receive prefetch operations for at least one of the levels of cache. A refresh controller is configured to determine addresses within each level of cache that are due for a refresh. The refresh controller is configured to assert a refresh write-in signal to write data supplied from the pending write queue specified for an address due for a refresh rather than refresh existing data. The refresh controller asserts the refresh write-in signal in response to a determination that there is pending data to supply to the address specified to have the refresh.

Abstract: A method of integrating a hybrid architecture in a set associative cache having a first type of memory structure for one or more ways in each congruence class, and a second type of memory structure for the remaining ways of the congruence class, includes determining whether a memory access request results in a cache hit or a cache miss; in the event of a cache miss, determining whether LRU way of the first type memory structure is also the LRU way of the entire congruence class, and if not, then copying the contents of the LRU way of the first type memory structure into the LRU way of the entire congruence class, and filling the LRU way of the first type memory structure with a new cache line in the event of a cache miss; and updating LRU bits, depending upon the results of the memory access request.

Abstract: A method for implementing dynamic refresh protocols for DRAM based cache includes partitioning a DRAM cache into a refreshable portion and a non-refreshable portion, and assigning incoming individual cache lines to one of the refreshable portion and the non-refreshable portion of the cache based on a usage history of the cache lines. Cache lines corresponding to data having a usage history below a defined frequency are assigned to the refreshable portion of the cache, and cache lines corresponding to data having a usage history at or above the defined frequency are assigned to the non-refreshable portion of the cache.

Abstract: A hardware description language (HDL) design structure embodied on a machine-readable data storage medium includes elements that when processed in a computer aided design system generates a machine executable representation of a device for implementing dynamic refresh protocols for DRAM based cache. The HDL design structure further includes a DRAM cache partitioned into a refreshable portion and a non-refreshable portion; and a cache controller configured to assign incoming individual cache lines to one of the refreshable portion and the non-refreshable portion of the cache based on a usage history of the cache lines; wherein cache lines corresponding to data having a usage history below a defined frequency are assigned by the controller to the refreshable portion of the cache, and cache lines corresponding to data having a usage history at or above the defined frequency are assigned to the non-refreshable portion of the cache.

Abstract: An apparatus for implementing a refreshless, embedded dynamic random access memory (eDRAM) cache device includes a cache structure having a cache tag array associated with a DRAM data cache with a plurality of cache lines, the cache tag array having an address tag, a valid bit and an access bit corresponding to each of the plurality of cache lines; and each access bit configured to indicate whether the corresponding cache line has been accessed as a result of a read or a write operation during a defined assessment period, the defined assessment period being smaller than retention time of data in the DRAM data cache. For any of the cache lines that have not been accessed during the defined assessment period, the individual valid bit associated therewith is set to a logic state that indicates the data in the associated cache line is invalid.

Abstract: A design structure embodied in a machine readable medium used in a design process includes a cache structure having a cache tag array associated with a eDRAM data cache comprising a plurality of cache lines, the cache tag array having an address tag, a valid bit and an access bit corresponding to each of the plurality of cache lines; and each access bit configured to indicate whether the corresponding cache line has been accessed as a result of a read or a write operation during a defined assessment period, which is smaller than retention time of data in the DRAM data cache; wherein, for any of the cache lines not accessed as a result of a read or a write operation during the defined assessment period, the individual valid bit associated therewith is set to a logic state that indicates the data in the associated cache line is invalid.

Abstract: A method for monitoring event occurrences from a plurality of processor units at a centralized location via a dedicated bus coupled between the plurality of processor units and the centralized location. In particular, the method comprises receiving, at the centralized location, data indicative of cumulative events occurring at one of the processor units, and storing the data in a first temporary memory. The data is then stored in a register based on a tag identifier affixed to the data in an instance where the tag identifier provides indicia of one of the plurality of processor units.

Abstract: A method for monitoring event occurrences from a plurality of processor units at a centralized location via a dedicated bus coupled between the plurality of processor units and the centralized location. In particular, the method comprises receiving, at the centralized location, data indicative of cumulative events occurring at one of the processor units, and storing the data in a first temporary memory. The data is then stored in a register based on a tag identifier affixed to the data in an instance where the tag identifier provides indicia of one of the plurality of processor units.

Abstract: A method for monitoring event occurrences from a plurality of processor units at a centralized location via a dedicated bus coupled between the plurality of processor units and the centralized location. In particular, the method comprises receiving, at the centralized location, data indicative of cumulative events occurring at one of the processor units, and storing the data in a first temporary memory. The data is then stored in a register based on a tag identifier affixed to the data in an instance where the tag identifier provides indicia of one of the plurality of processor units.

Abstract: Method and apparatus for monitoring event occurrences, e.g., from an event signal, where a register and a counter are employed. In one embodiment, the register is designed to have a capture bit for capturing the occurrence of a monitored event. The shifting of the stored information within the capture bit to other bit locations within the register is controlled by a shift rate signal operating at a particular interval time period. At the expiration of the interval time period, the stored information in the capture bit is shifted within the register, where the capture bit is now free to detect the next occurrence of the monitored event. Since the register has a finite number of bit locations, as the captured information exists and/or enters the register, a counter is triggered to record the number of occurrences of monitored events.