Abstract: A memory controller provides programmable flexibility, via one or more configuration registers, for the configuration of the memory. The memory may be optimized for a given application by programming the configuration registers. For example, in one embodiment, the portion of the address of a memory transaction used to select a storage location for access in response to the memory transaction may be programmable. In an implementation designed for DRAM, a first portion may be programmably selected to form the row address and a second portion may be programmable selected to form the column address. Additional embodiments may further include programmable selection of the portion of the address used to select a bank. Still further, interleave modes among memory sections assigned to different chip selects and among two or more channels to memory may be programmable, in some implementations.

Abstract: A cache is coupled to receive an access which includes a cache allocate indication. If the access is a miss in the cache, the cache either allocates a cache block storage location to store the cache block addressed by the access or does not allocate a cache block storage location in response to the cache allocate indication. In one implementation, the cache is coupled to an interconnect with one or more agents. In such an implementation, the cache accesses may be performed in response to transactions on the interconnect, and the transactions include the cache allocate indication. Thus, the source of a cache access specifies whether or not to allocate a cache block storage location in response to a miss by the cache access. The source may use a variety of mechanisms for generating the cache allocate indication.

Abstract: A packet processing system may include a processor, a cache, a memory controller, and at least one packet interface circuit integrated into a single integrated circuit. In one embodiment (which may be used in integrated or non-integrated systems), the packet interface circuit is configured to cause allocation in the cache of a portion of a received packet. In one embodiment (which may be used in integrated or non-integrated systems), the memory controller may be configured to selectively block memory transactions. Particularly, the memory controller may implement at least two block signals, one for the packet interface circuit and one for other devices. The block signals may be used to control the initiation of memory transactions when the memory controller's input queue is approaching fullness.

Abstract: A cache is coupled to receive an access which includes a cache allocate indication. If the access is a miss in the cache, the cache either allocates a cache block storage location to store the cache block addressed by the access or does not allocate a cache block storage location in response to the cache allocate indication. In one implementation, the cache is coupled to an interconnect with one or more agents. In such an implementation, the cache accesses may be performed in response to transactions on the interconnect, and the transactions include the cache allocate indication. Thus, the source of a cache access specifies whether or not to allocate a cache block storage location in response to a miss by the cache access. The source may use a variety of mechanisms for generating the cache allocate indication.

Abstract: A packet processing system may include a processor, a cache, a memory controller, and at least one packet interface circuit integrated into a single integrated circuit. In one embodiment (which may be used in integrated or non-integrated systems), the packet interface circuit is configured to cause allocation in the cache of a portion of a received packet. In one embodiment (which may be used in integrated or non-integrated systems), the memory controller may be configured to selectively block memory transactions. Particularly, the memory controller may implement at least two block signals, one for the packet interface circuit and one for other devices. The block signals may be used to control the initiation of memory transactions when the memory controller's input queue is approaching fullness.

Abstract: A system on a chip for network devices. In one implementation, the system on a chip may include (integrated onto a single integrated circuit), a processor and one or more I/O devices for networking applications. For example, the I/O devices may include one or more network interface circuits for coupling to a network interface. In one embodiment, coherency may be enforced within the boundaries of the system on a chip but not enforced outside of the boundaries.