Abstract: A memory device includes a memory array and a memory controller operatively coupled to the memory array. The memory array includes memory cells to store memory data. The memory controller includes a prefetch buffer, a read address buffer including memory registers to store addresses of memory read requests received from at least one separate device, and logic circuitry. The logic circuitry is configured to store extra read data in the prefetch buffer when an address of a read request is a continuous address of an address stored in the read address buffer, and omit prefetching the extra data when the address of the read request is a non-continuous address of an address stored in the read address buffer.

Abstract: A processor system includes a processor core, a cache, a cache controller, and a cache assist controller. The processor core issues a read/write command for reading data from or writing data to a memory. The processor core also outputs an address range specifying addresses for which the cache assist controller can return zero fill, e.g., an address range for the read/write command. The cache controller transmits a cache request to the cache assist controller based on the read/write command. The cache assist controller receives the address range output by the processor core and compares the address range to the cache request. If a memory address in the cache request falls within the address range, the cache assist controller returns a string of zeroes, rather than fetching and returning data stored at the memory address.

Abstract: A processor system includes a processor core, a cache, a cache controller, and a cache assist controller. The processor core issues a read/write command for reading data from or writing data to a memory. The processor core also outputs an address range specifying addresses for which the cache assist controller can return zero fill, e.g., an address range for the read/write command. The cache controller transmits a cache request to the cache assist controller based on the read/write command. The cache assist controller receives the address range output by the processor core and compares the address range to the cache request. If a memory address in the cache request falls within the address range, the cache assist controller returns a string of zeroes, rather than fetching and returning data stored at the memory address.

Abstract: Digital signal processors often operate on two operands per instruction, and it is desirable to retrieve both operands in one cycle. Some data caches connect to the processor over two busses and internally uses two or more memory banks to store cache lines. The allocation of cache lines to specific banks is based on the address that the cache line is associated. When two memory accesses map to the same memory bank, fetching the operands incurs extra latency because the accesses are serialized. An improved bank organization for providing conflict-free dual-data cache access—a bus-based data cache system having two data buses and two memory banks—is disclosed. Each memory bank works as a default memory bank for the corresponding data bus. As long as the two values of data being accessed belong to two separate data sets assigned to the two respective data buses, memory bank conflicts are avoided.

Abstract: Digital signal processors often operate on two operands per instruction, and it is desirable to retrieve both operands in one cycle. Some data caches connect to the processor over two busses and internally uses two or more memory banks to store cache lines. The allocation of cache lines to specific banks is based on the address that the cache line is associated. When two memory accesses map to the same memory bank, fetching the operands incurs extra latency because the accesses are serialized. An improved bank organization for providing conflict-free dual-data cache access—a bus-based data cache system having two data buses and two memory banks—is disclosed. Each memory bank works as a default memory bank for the corresponding data bus. As long as the two values of data being accessed belong to two separate data sets assigned to the two respective data buses, memory bank conflicts are avoided.

Abstract: The present invention provides an improved technique for performing a near processing path exponent difference in an arithmetic logic unit (ALU) of a microprocessor. In one embodiment, an apparatus having a separate logic circuit for near processing path and far processing path subtraction generates exponent difference signals using only two least significant bits of exponents of the two floating point operands to perform the exponent difference.

Abstract: The present invention provides an improved technique for performing a near processing path exponent difference in an arithmetic logic unit (ALU) of a microprocessor. In one embodiment, an apparatus having a separate logic circuit for near processing path and far processing path subtraction generates exponent difference signals using only two least significant bits of exponents of the two floating point operands to perform the exponent difference.