摘要:
A method for generating a local clock domain within an operation includes steps of: receiving a clock frequency measurement for a slow portion of logic within the operation; generating a local signal to indicate commencement of the operation and to function as a clock gating signal; latching the clock gating signal to a selected cycle; generating clock domain controls based on the clock gating signal such that the operation times its commencement on the selected cycle; and propagating the clock gating signal in ungated latches for a number of cycles, such that a second operation is restricted from being launched until the operation completes.
摘要:
A method for generating a local clock domain within an operation includes steps of: receiving a clock frequency measurement for a slow portion of logic within the operation; generating a local signal to indicate commencement of the operation and to function as a clock gating signal; latching the clock gating signal to a selected cycle; generating clock domain controls based on the clock gating signal such that the operation times itscommencement on the selected cycle; and propagating the clock gating signal in ungated latches for a number of cycles, such that a second operation is restricted from being launched until the operation completes.
摘要:
A method for handling errors in a cache memory without processor core recovery includes receiving a fetch request for data from a processor and simultaneously transmitting fetched data and a parity matching the parity of the fetched data to the processor. The fetched data is received from a higher-level cache into a low level cache of the processor. Upon determining that the fetched data failed an error check indicating that the fetched data is corrupted, the method includes requesting an execution pipeline to discontinue processing and flush its contents, and initiating a clean up sequence, which includes sending an invalidation request to the low level cache causing the low level cache to remove lines associated with the corrupted data, and requesting the execution pipeline to restart. The execution pipeline accesses a copy of the requested data from a higher-level storage location.
摘要:
Method and system for a multi-level virtual/real cache system with synonym resolution. An exemplary embodiment includes a multi-level cache hierarchy, including a set of L1 caches associated with one or more processor cores and a set of L2 caches, wherein the set of L1 caches are a subset of the set of L2 caches, wherein the set of L1 caches underneath a given L2 cache are associated with one or more of the processor cores.
摘要:
Method and system for a multi-level virtual/real cache system with synonym resolution. An exemplary embodiment includes a multi-level cache hierarchy, including a set of L1 caches associated with one or more processor cores and a set of L2 caches, wherein the set of L1 caches are a subset of the set of L2 caches, wherein the set of L1 caches underneath a given L2 cache are associated with one or more of the processor cores.
摘要:
A method for handling errors in a cache memory without processor core recovery includes receiving a fetch request for data from a processor and simultaneously transmitting fetched data and a parity matching the parity of the fetched data to the processor. The fetched data is received from a higher-level cache into a low level cache of the processor. Upon determining that the fetched data failed an error check indicating that the fetched data is corrupted, the method includes requesting an execution pipeline to discontinue processing and flush its contents, and initiating a clean up sequence, which includes sending an invalidation request to the low level cache causing the low level cache to remove lines associated with the corrupted data, and requesting the execution pipeline to restart. The execution pipeline accesses a copy of the requested data from a higher-level storage location.
摘要:
A method for handling cache coherency includes allocating a tag when a cache line is not exclusive in a data cache for a store operation, and sending the tag and an exclusive fetch for the line to coherency logic. An invalidation request is sent within a minimum amount of time to an I-cache, preferably only if it has fetched to the line and has not been invalidated since, which request includes an address to be invalidated, the tag, and an indicator specifying the line is for a PSC operation. The method further includes comparing the request address against stored addresses of prefetched instructions, and in response to a match, sending a match indicator and the tag to an LSU, within a maximum amount of time. The match indicator is timed, relative to exclusive data return, such that the LSU can discard prefetched instructions following execution of the store operation that stores to a line subject to an exclusive data return, and for which the match is indicated.
摘要:
A method for handling cache coherency includes allocating a tag when a cache line is not exclusive in a data cache for a store operation, and sending the tag and an exclusive fetch for the line to coherency logic. An invalidation request is sent within a minimum amount of time to an I-cache, preferably only if it has fetched to the line and has not been invalidated since, which request includes an address to be invalidated, the tag, and an indicator specifying the line is for a PSC operation. The method further includes comparing the request address against stored addresses of prefetched instructions, and in response to a match, sending a match indicator and the tag to an LSU, within a maximum amount of time. The match indicator is timed, relative to exclusive data return, such that the LSU can discard prefetched instructions following execution of the store operation that stores to a line subject to an exclusive data return, and for which the match is indicated.
摘要:
Embodiments relate to controlling observability of transactional and non-transactional stores. An aspect includes receiving one or more store instructions. The one or more store instructions are initiated within an active transaction and include store data. The active transaction effectively delays committing stores to memory until successful completion of the active transaction. The store data is stored in a local storage buffer causing alterations to the local storage buffer from a first state to a second state. A signal is received that the active transaction has terminated. If the active transaction has terminated abnormally then: the local storage buffer is reverted back to the first state if the store data was stored by a transactional store instruction, and is propagated to a shared cache if the store instruction is non-transactional.
摘要:
A mechanism is provided for avoiding cross-interrogates for a streaming data optimized level one cache. The mechanism adds a set of dedicated registers, referred to as “copex registers,” to track ownership of the cache lines that the co-processor's L1 cache holds exclusive. The mechanism extends the cache directory of the L2 cache by a bit that identifies exclusive ownership of a cache line in the co-processor cache. The co-processor continuously provides an indication of which copex registers are valid. On any action that requires a directory lookup in the L2 cache, the mechanism compares the valid copex registers against the lookup address in parallel to the directory lookup. The mechanism considers the “exclusive ownership in co-processor” bit in the directory valid only if the cache line is also currently in a valid copex register.