Abstract: In examples, a device comprises control logic configured to detect an idle cycle, an operand generator configured to provide a synthetic operand responsive to the detection of the idle cycle, and a computational circuit. The computational circuit is configured to, during the idle cycle, perform a first computation on the synthetic operand. The computational circuit is configured to, during an active cycle, perform a second computation on an architectural operand.

Abstract: In an example, a device includes a memory and a processor core coupled to the memory via a memory management unit (MMU). The device also includes a system MMU (SMMU) cross-referencing virtual addresses (VAs) with intermediate physical addresses (IPAs) and IPAs with physical addresses (PAs). The device further includes a physical address table (PAT) cross-referencing IPAs with each other and cross-referencing PAs with each other. The device also includes a peripheral virtualization unit (PVU) cross-referencing IPAs with PAs, and a routing circuit coupled to the memory, the SMMU, the PAT, and the PVU. The routing circuit is configured to receive a request comprising an address and an attribute and to route the request through at least one of the SMMU, the PAT, or the PVU based on the address and the attribute.

Abstract: In an example, a device includes a memory and a processor core coupled to the memory via a memory management unit (MMU). The device also includes a system MMU (SMMU) cross-referencing virtual addresses (VAs) with intermediate physical addresses (IPAs) and IPAs with physical addresses (PAs). The device further includes a physical address table (PAT) cross-referencing IPAs with each other and cross-referencing PAs with each other. The device also includes a peripheral virtualization unit (PVU) cross-referencing IPAs with PAs, and a routing circuit coupled to the memory, the SMMU, the PAT, and the PVU. The routing circuit is configured to receive a request comprising an address and an attribute and to route the request through at least one of the SMMU, the PAT, or the PVU based on the address and the attribute.

Abstract: In an example, a device includes a memory and a processor core coupled to the memory via a memory management unit (MMU). The device also includes a system MMU (SMMU) cross-referencing virtual addresses (VAs) with intermediate physical addresses (IPAs) and IPAs with physical addresses (PAs). The device further includes a physical address table (PAT) cross-referencing IPAs with each other and cross-referencing PAs with each other. The device also includes a peripheral virtualization unit (PVU) cross-referencing IPAs with PAs, and a routing circuit coupled to the memory, the SMMU, the PAT, and the PVU. The routing circuit is configured to receive a request comprising an address and an attribute and to route the request through at least one of the SMMU, the PAT, or the PVU based on the address and the attribute.

Abstract: In an example, a device includes a memory and a processor core coupled to the memory via a memory management unit (MMU). The device also includes a system MMU (SMMU) cross-referencing virtual addresses (VAs) with intermediate physical addresses (IPAs) and IPAs with physical addresses (PAs). The device further includes a physical address table (PAT) cross-referencing IPAs with each other and cross-referencing PAs with each other. The device also includes a peripheral virtualization unit (PVU) cross-referencing IPAs with PAs, and a routing circuit coupled to the memory, the SMMU, the PAT, and the PVU. The routing circuit is configured to receive a request comprising an address and an attribute and to route the request through at least one of the SMMU, the PAT, or the PVU based on the address and the attribute.

Abstract: In an example, a device includes a memory and a processor core coupled to the memory via a memory management unit (MMU). The device also includes a system MMU (SMMU) cross-referencing virtual addresses (VAs) with intermediate physical addresses (IPAs) and IPAs with physical addresses (PAs). The device further includes a physical address table (PAT) cross-referencing IPAs with each other and cross-referencing PAs with each other. The device also includes a peripheral virtualization unit (PVU) cross-referencing IPAs with PAs, and a routing circuit coupled to the memory, the SMMU, the PAT, and the PVU. The routing circuit is configured to receive a request comprising an address and an attribute and to route the request through at least one of the SMMU, the PAT, or the PVU based on the address and the attribute.

Abstract: Embodiments are generally directed to a multithreaded processor for executing a plurality of threads, as well as an associated method and system. The multithreaded processor comprises a first control register configured to store a stack limit value, and instruction decode logic configured to, upon receiving a procedure entry instruction for a stack associated with a first thread, determine whether to throw a stack limit exception based on the stack limit value and a first predefined stack region size associated with the stack.

Abstract: Embodiments are generally directed to a multithreaded processor for executing a plurality of threads, as well as an associated method and system. The multithreaded processor comprises a first control register configured to store a stack limit value, and instruction decode logic configured to, upon receiving a procedure entry instruction for a stack associated with a first thread, determine whether to throw a stack limit exception based on the stack limit value and a first predefined stack region size associated with the stack.

Abstract: A system and method includes modules for determining whether an instruction is a target of a non-sequential fetch operation with an expected numerical property value, and avoiding execution of the instruction if it is the target of the non-sequential fetch operation and does not have the expected numerical property. Other embodiments include encoding an instruction with a functionality that is a target of a non-sequential fetch operation with an expected numerical property value. Instructions with the same functionality that are not targets of non-sequential fetch operations can be encoded with a different numerical property value. More specific embodiments can include a numerical property of parity, determining whether the instruction is valid, and throwing an exception, setting status bits, sending an interrupt to a control processor, and a combination thereof to avoid execution.

Abstract: A system and method includes modules for determining whether an instruction is a target of a non-sequential fetch operation with an expected numerical property value, and avoiding execution of the instruction if it is the target of the non-sequential fetch operation and does not have the expected numerical property. Other embodiments include encoding an instruction with a functionality that is a target of a non-sequential fetch operation with an expected numerical property value. Instructions with the same functionality that are not targets of non-sequential fetch operations can be encoded with a different numerical property value. More specific embodiments can include a numerical property of parity, determining whether the instruction is valid, and throwing an exception, setting status bits, sending an interrupt to a control processor, and a combination thereof to avoid execution.

Abstract: The present invention provides a network multithreaded processor, such as a network processor, including a thread interleaver that implements fine-grained thread decisions to avoid underutilization of instruction execution resources in spite of large communication latencies. In an upper pipeline, an instruction unit determines an-instruction fetch sequence responsive to an instruction queue depth on a per thread basis. In a lower pipeline, a thread interleaver determines a thread interleave sequence responsive to thread conditions including thread latency conditions. The thread interleaver selects threads using a two-level round robin arbitration. Thread latency signals are active responsive to thread latencies such as thread stalls, cache misses, and interlocks. During the subsequent one or more clock cycles, the thread is ineligible for arbitration. In one embodiment, other thread conditions affect selection decisions such as local priority, global stalls, and late stalls.

Abstract: Multiple pipelined Translation Look-aside Buffer (TLB) units are configured to compare a translation address with associated TLB entries. The TLB units operated in serial order comparing the translation address with associated TLB entries until an identified one of the TLB units produces a hit. The TLB units following the TLB unit producing the hit might be disabled.

Abstract: A processing engine includes descriptor transfer logic that receives descriptors generated by a software controlled general purpose processing element. The descriptor transfer logic manages transactions that send the descriptors to resources for execution and receive responses back from the resources in response to the sent descriptors. The descriptor transfer logic can manage the allocation and operation of buffers and registers that initiate the transaction, track the status of the transaction, and receive the responses back from the resources all on behalf of the general purpose processing element.

Abstract: A network processor has numerous novel features including a multi-threaded processor array, a multi-pass processing model, and Global Packet Memory (GPM) with hardware managed packet storage. These unique features allow the network processor to perform high-touch packet processing at high data rates. The packet processor can also be coded using a stack-based high-level programming language, such as C or C++. This allows quicker and higher quality porting of software features into the network processor. Processor performance also does not severely drop off when additional processing features are added. For example, packets can be more intelligently processed by assigning processing elements to different bounded duration arrival processing tasks and variable duration main processing tasks. A recirculation path moves packets between the different arrival and main processing tasks.

Abstract: Multiple pipelined Translation Look-aside Buffer (TLB) units are configured to compare a translation address with associated TLB entries. The TLB units operated in serial order comparing the translation address with associated TLB entries until an identified one of the TLB units produces a hit. The TLB units following the TLB unit producing the hit might be disabled.

Abstract: The present invention provides a network multithreaded processor, such as a network processor, including a thread interleaver that implements fine-grained thread decisions to avoid underutilization of instruction execution resources in spite of large communication latencies. In an upper pipeline, an instruction unit determines an-instruction fetch sequence responsive to an instruction queue depth on a per thread basis. In a lower pipeline, a thread interleaver determines a thread interleave sequence responsive to thread conditions including thread latency conditions. The thread interleaver selects threads using a two-level round robin arbitration. Thread latency signals are active responsive to thread latencies such as thread stalls, cache misses, and interlocks. During the subsequent one or more clock cycles, the thread is ineligible for arbitration. In one embodiment, other thread conditions affect selection decisions such as local priority, global stalls, and late stalls.

Abstract: The present invention provides a multithreaded processor, such as a network processor, that fetches instructions in a pipeline stage based on feedback signals from later stages. The multithreaded processor comprises a pipeline with an instruction unit in the early stage and an instruction queue, a thread interleaver, and an execution pipeline in the later stages. Feedback signals from the later stages cause the instruction unit to block fetching, immediately fetch, raise priority, or lower priority for a particular thread. The instruction queue generates a queue signal, on a per thread basis, responsive to a thread queue condition, etc., the thread interleaver generates an interleaver signal responsive to a thread condition, etc., and the execution pipeline generates an execution signal responsive to an execution stall, etc.

Abstract: A subpipelined translation embodiment provides binary compatibility between current an future generations of DSPs. When retrieved from memory an entire fetch packet is assigned an operating mode (base instruction set or migrant instruction set) according to the current execution mode. The fetch packets from the instruction memory are parsed into execute packets and sorted by execution unit (dispatched) in a datapath shared by both execution modes (base and migrant). The two execution modes have separate control logic. Instructions from the dispatch datapath are decoded by either base architecture decode logic or the migrant architecture decode logic, depending on the execution mode bound to the parent fetch packet. Code processed by the migrant and base decode pipelines produces machine words that are selected by a multiplexer. The multiplexer is controlled by the operating mode bound to the fetch packet that produced the machine word.

Abstract: A method for processing data is provided that includes storing a write operation in a store buffer that indicates a first data element is to be written to a memory array element. The write operation includes a first address associated with a location in the memory array element to where the first data element is to be written. A read operation may be received at the store buffer, indicating that a second data element is to be read from the memory array element. The read operation includes a second address associated with a location in the memory array element from where the second data element is to be read. A hashing operation may be executed on the first and second addresses such that first and second hashed addresses are respectively produced. The hashed addresses are compared. If they match, the first data element is written to the memory array element before the read operation is executed.

Abstract: A flip flop (30) comprising a master stage (34) comprising a first plurality of transistors (54, 56), wherein each of the first plurality of transistors comprises a selective conductive path between a source and drain. The flip flop also comprises a slave stage (42) comprising a second plurality of transistors (60, 62, 64, 66), wherein each of the second plurality of transistors comprises a selective conductive path between a source and drain. For the flip flop, in a low power mode the flip flop is operable to receive a first voltage (VDD) coupled to the selective conductive path for each of the first plurality of transistors. Also in the low power mode, the flip flop is operable to receive a second voltage (VDDL) coupled to the selective conductive path for each of the second plurality of transistors. Lastly, the second voltage is greater than the first voltage in the low power mode.