摘要:
Power conservation via DRAM access reduction is provided by a buffer/mini-cache selectively operable in a normal mode and a buffer mode. In the buffer mode, entered when CPUs begin operating in low-power states, non-cacheable accesses (such as generated by a DMA device) matching specified physical address ranges are processed by the buffer/mini-cache, instead of by a memory controller and DRAM. The buffer/mini-cache processing includes allocating lines when references miss, and returning cached data from the buffer/mini-cache when references hit. Lines are replaced in the buffer/mini-cache according to one of a plurality of replacement policies, including ceasing replacement when there are no available free lines. In the normal mode, entered when CPUs begin operating in high-power states, the buffer/mini-cache operates akin to a conventional cache and non-cacheable accesses are not processed therein. In one usage scenario, data retained in the buffer/mini-cache is graphics refresh data maintained in a compressed format metal layer on the second electrically
摘要:
Power conservation via DRAM access reduction is provided by a buffer/mini-cache selectively operable in a normal mode and a buffer mode. In the buffer mode, entered when CPUs begin operating in low-power states, non-cacheable accesses (such as generated by a DMA device) matching specified physical address ranges are processed by the buffer/mini-cache, instead of by a memory controller and DRAM. The buffer/mini-cache processing includes allocating lines when references miss, and returning cached data from the buffer/mini-cache when references hit. Lines are replaced in the buffer/mini-cache according to one of a plurality of replacement policies, including ceasing replacement when there are no available free lines. In the normal mode, entered when CPUs begin operating in high-power states, the buffer/mini-cache operates akin to a conventional cache and non-cacheable accesses are not processed therein. In one usage scenario, data retained in the buffer/mini-cache is graphics refresh data maintained in a compressed format.
摘要:
A small and power-efficient buffer/mini-cache sources and sinks selected DMA accesses directed to a memory space included in a coherency domain of a microprocessor when cached data in the microprocessor is inaccessible due to any or all of the microprocessor being in a low-power state not supporting snooping. Satisfying the selected DMA accesses via the buffer/mini-cache enables reduced power consumption by allowing the microprocessor (or portion thereof) to remain in the low-power state. The buffer/mini-cache may be operated (temporarily) incoherently with respect to the cached data in the microprocessor and flushed before deactivation to synchronize with the cached data when the microprocessor (or portion thereof) transitions to a high-power state that enables snooping. Alternatively the buffer/mini-cache may be operated in a manner (incrementally) coherent with the cached data. The microprocessor implements one or more processors having associated cache systems (such as various arrangements of first-, second-, and higher-level caches).
摘要:
The present disclosure provides methods and systems adapted for use with a processor having one or more physical cores. The methods and systems include a virtual core management component adapted to map one or more virtual cores to at least one of the physical cores to enable execution of one or more programs by the at least one physical core. The one or more virtual cores include one or more logical states associated with the execution of the one or more programs. The methods and systems may include a memory component adapted to store the one or more virtual cores. The virtual core management component may be adapted to transfer the one or more virtual cores from the memory component to the at least one physical core.
摘要:
A multiprocessor switching device substantially implemented on a single CMOS integrated circuit is described in connection with a parallel routing scheme for calculating routing information for incoming packets. Using the programmable hash and route routing scheme, a hash and route circuit can be programmed for a variety of applications, such as routing, flow-splitting or load balancing.
摘要:
An integrated circuit includes receive circuits for receiving packets, transmit circuits for transmitting packets, a packet DMA circuit for communicating packets to and from a memory controller, and a switch for selectively coupling the receive circuits to transmit circuits. The integrated circuit may flexibly merge and split the packet streams to provide for various packet processing/packet routing functions to be applied to different packets within the packet streams. An apparatus may include two or more of the integrated circuits, which may communicate packets between respective receive and transmit circuits.
摘要:
A system for synchronizing configuration information in a plurality of data processing devices using a common system interconnect bus. The present invention provides a method and apparatus for enforcing automatic updates to the configuration registers in various agents in the data processing system. A node controller is operably connected to a system interconnect bus and a switch. A plurality of interface agents are connected to the switch, with each of the interface agents comprising a configuration space register, a configuration space shadow register and a control and status register (CSR). A token ring connected to the node controller is operable to transmit data from the node controller to a plurality of interface agents connected to the token ring, thereby providing a system for updating the various configuration registers in each of the agents.
摘要:
In accordance with the present invention, an integrated circuit system and method are provided for increasing the number of processors on a single integrated circuit to a number that is larger than would typically be possible to coordinate on a single bus. In the present invention a two-level memory coherency scheme is implemented for use by multiple processors operably connected to multiple buses in the same integrated circuit. A control device, such as node controller, is used to control traffic between the two coherency levels. In one embodiment of the invention the first level of coherency is implemented using a “snoopy” protocol and the second level of coherency is a directory-based coherency scheme. In some embodiments of the invention, the directory-based coherency scheme is implemented using a centralized memory and directory architecture. In other embodiments of the invention, the second level of coherency is implemented using distributed memory and a distributed directory. In another alternate embodiment of the invention, a third level of coherency is implemented for transfer of data externally from the integrated circuit.
摘要:
A multi-dimension engine, connected to a system TLB, generates sequences of addresses to request page address translation prefetch requests in advance of predictable accesses to elements within data arrays. Prefetch requests are filtered to avoid redundant requests of translations to the same page. Prefetch requests run ahead of data accesses but are tethered to within a reasonable range. The number of pending prefetches are limited. A system TLB stores a number of translations, the number being relative to the dimensions of the range of elements accessed from within the data array.
摘要:
A system and method are disclosed for connecting PCI-ordered agents based on fully independent networks. The system and method are free of PCI topology constraints, so that the system and method can be implemented in an inexpensive and scalable way. The method disclosed is used to handle and transport PCI-ordered traffic on a fabric. Based on the actual ordering requirement of the set of PCI agents, the fabric includes two, three, or four independent networks.