Abstract: An island-based network flow processor (IB-NFP) integrated circuit includes rectangular islands disposed in rows. In one example, the configurable mesh data bus is configurable to form a command/push/pull data bus over which multiple transactions can occur simultaneously on different parts of the integrated circuit. The rectangular islands of one row are oriented in staggered relation with respect to the rectangular islands of the next row. The left and right edges of islands in a row align with left and right edges of islands two rows down in the row structure. The data bus involves multiple meshes. In each mesh, the island has a centrally located crossbar switch and six radiating half links, and half links down to functional circuitry of the island. The staggered orientation of the islands, and the structure of the half links, allows half links of adjacent islands to align with one another.

Abstract: A transactional memory (TM) receives a lookup command across a bus from a processor. The command includes a memory address. In response to the command, the TM pulls an input value (IV). The memory address is used to read a word containing multiple result values (RVs), multiple reference values, and multiple prefix values from memory. A selecting circuit within the TM uses a starting bit position and a mask size to select a portion of the IV. The portion of the IV is a lookup key value (LKV). Mask values are generated based on the prefix values. The LKV is masked by each mask value thereby generating multiple masked values that are compared to the reference values. Based on the comparison a lookup table generates a selector value that is used to select a result value. The selected result value is then communicated to the processor via the bus.

Abstract: A transactional memory (TM) receives an Atomic Metering Command (AMC) across a bus from a processor. The command includes a memory address and a meter pair indicator value. In response to the AMC, the TM pulls an input value (IV). The TM uses the memory address to read a word including multiple credit values from a memory unit. Circuitry within the TM selects a pair of credit values, subtracts the IV from each of the pair of credit values thereby generating a pair of decremented credit values, compares the pair of decremented credit values with a threshold value, respectively, thereby generating a pair of indicator values, performs a lookup based upon the pair of indicator values and the meter pair indicator value, and outputs a selector value and a result value that represents a meter color. The selector value determines the credit values written back to the memory unit.

Abstract: A chained Command/Push/Pull (CPP) bus command is output by a first device and is sent from a CPP bus master interface across a set of command conductors of a CPP bus to a second device. The chained CPP command includes a reference value. The second device decodes the command, in response determines a plurality of CPP commands, and outputs the plurality of CPP commands onto the CPP bus. The second device detects when the plurality of CPP commands have been completed, and in response returns the reference value back to the CPP bus master interface of the first device via a set of data conductors of the CPP bus. The reference value indicates to the first device that an overall operation of the chained CPP command has been completed.

Abstract: An addressless merge command includes an identifier of an item of data, and a reference value, but no address. A first part of the item is stored in a first place. A second part is stored in a second place. To move the first part so that the first and second parts are merged, the command is sent across a bus to a device. The device translates the identifier into a first address ADR1, and uses ADR1 to read the first part. Stored in or with the first part is a second address ADR2 indicating where the second part is stored. The device extracts ADR2, and uses ADR1 and ADR2 to issue bus commands. Each bus command causes a piece of the first part to be moved. When the entire first part has been moved, then device returns the reference value to indicate that the merge command has been completed.

Abstract: A transactional memory (TM) includes a control circuit pipeline and an associated memory unit. The memory unit stores a plurality of rings. The pipeline maintains, for each ring, a head pointer and a tail pointer. A ring operation stage of the pipeline maintains the pointers as values are put onto and are taken off the rings. A put command causes the TM to put a value into a ring, provided the ring is not full. A get command causes the TM to take a value off a ring, provided the ring is not empty. A put with low priority command causes the TM to put a value into a ring, provided the ring has at least a predetermined amount of free buffer space. A get from a set of rings command causes the TM to get a value from the highest priority non-empty ring (of a specified set of rings).

Abstract: A high-speed credit-based allocator circuit receives an allocation request to make an allocation to one of a set of a processing entities. The allocator circuit maintains a chain of bubble sorting module circuits for the set, where each bubble sorting module circuit stores a resource value and an indication of a corresponding processing entity. A bubble sorting operation is performed so that the head of the chain tends to indicate the processing entity of the set that has the highest amount of the resource (credit) available. The allocation requested is made to the processing entity indicated by the head module circuit of the chain. The amount of the resource available to each processing entity is tracked by adjusting the resource values as allocations are made, and as allocated tasks are completed. The allocator circuit is configurable to maintain multiple chains, thereby supporting credit-based allocations to multiple sets of processing entities.

Abstract: Within a networking device, packet portions from multiple PDRSDs (Packet Data Receiving and Splitting Devices) are loaded into a single memory, so that the packet portions can later be processed by a processing device. Rather than the PDRSDs managing and handling the storing of packet portions into the memory, a packet engine is provided. The PDRSDs use a PPI (Packet Portion Identifier) Addressing Mode (PAM) in communicating with the packet engine and in instructing the packet engine to store packet portions. A PDRSD requests a PPI from the packet engine in a PPI allocation request, and is allocated a PPI by the packet engine in a PPI allocation response, and then tags the packet portion to be written with the PPI and sends the packet portion and the PPI to the packet engine.

Abstract: Within a networking device, packet portions from multiple PDRSDs (Packet Data Receiving and Splitting Devices) are loaded into a single memory, so that the packet portions can later be processed by a processing device. Rather than the PDRSDs managing and handling the storing of packet portions into the memory, a packet engine is provided. The PDRSDs use a PPI (Packet Portion Identifier) Addressing Mode (PAM) in communicating with the packet engine and in instructing the packet engine to store packet portions. The packet engine uses linear memory addressing to write the packet portions into the memory, and to read the packet portions from the memory.

Abstract: Within a networking device, packet portions from multiple PDRSDs (Packet Data Receiving and Splitting Devices) are loaded into a single memory, so that the packet portions can later be processed by a processing device. Rather than the PDRSDs managing and handling the storing of packet portions into the memory, a packet engine is provided. A device interacting with the packet engine can use a PPI (Packet Portion Identifier) Addressing Mode (PAM) in communicating with the packet engine and in instructing the packet engine to store packet portions. Alternatively, the device can use a Linear Addressing Mode (LAM) to communicate with the packet engine. A PAM/LAM selection code field in a bus transaction value sent to the packet engine indicates whether PAM or LAM will be used.

Abstract: In response to receiving a novel “Return Available PPI Credits” command from a credit-aware device, a packet engine sends a “Credit To Be Returned” (CTBR) value it maintains for that device back to the credit-aware device, and zeroes out its stored CTBR value. The credit-aware device adds the credits returned to a “Credits Available” value it maintains. The credit-aware device uses the “Credits Available” value to determine whether it can issue a PPI allocation request. The “Return Available PPI Credits” command does not result in any PPI allocation or de-allocation. In another novel aspect, the credit-aware device is permitted to issue one PPI allocation request to the packet engine when its recorded “Credits Available” value is zero or negative. If the PPI allocation request cannot be granted, then it is buffered in the packet engine, and is resubmitted within the packet engine, until the packet engine makes the PPI allocation.

Abstract: In response to receiving a novel “Return Available PPI Credits” command from a credit-aware device, a packet engine sends a “Credit To Be Returned” (CTBR) value it maintains for that device back to the credit-aware device, and zeroes out its stored CTBR value. The credit-aware device adds the credits returned to a “Credits Available” value it maintains. The credit-aware device uses the “Credits Available” value to determine whether it can issue a PPI allocation request. The “Return Available PPI Credits” command does not result in any PPI allocation or de-allocation. In another novel aspect, the credit-aware device is permitted to issue one PPI allocation request to the packet engine when its recorded “Credits Available” value is zero or negative. If the PPI allocation request cannot be granted, then it is buffered in the packet engine, and is resubmitted within the packet engine, until the packet engine makes the PPI allocation.

Abstract: Within a networking device, packet portions from multiple PDRSDs (Packet Data Receiving and Splitting Devices) are loaded into a single memory, so that the packet portions can later be processed by a processing device. Rather than the PDRSDs managing the storing of packet portions into the memory, a packet engine is provided. The PDRSDs use a PPI addressing mode in communicating with the packet engine and in instructing the packet engine to store packet portions. A PDRSD requests a PPI from the packet engine, and is allocated a PPI by the packet engine, and then tags the packet portion to be written with the PPI and sends the packet portion and the PPI to the packet engine. Once the packet portion has been processed, a PPI de-allocation command causes the packet engine to de-allocate the PPI so that the PPI is available for allocating in association with another packet portion.

Abstract: A transactional memory (TM) includes a selectable bank of hardware algorithm prework engines, a selectable bank of hardware lookup engines, and a memory unit. The memory unit stores result values (RVs), instructions, and lookup data operands. The transactional memory receives a lookup command across a bus from one of a plurality of processors. The lookup command includes a source identification value, data, a table number value, and a table set value. In response to the lookup command, the transactional memory selects one hardware algorithm prework engine and one hardware lookup engine to perform the lookup operation. The selected hardware algorithm prework engine modifies data included in the lookup command. The selected hardware lookup engine performs a lookup operation using the modified data and lookup operands provided by the memory unit. In response to performing the lookup operation, the transactional memory returns a result value and optionally an instruction.

Abstract: A novel allocate instruction and a novel API call are received onto a compiler. The allocate instruction includes a symbol that identifies a non-memory resource instance. The API call is a call to perform an operation on a non-memory resource instance, where the particular instance is indicated by the symbol in the API call. The compiler replaces the API call with a set of API instructions. A linker then allocates a value to be associated with the symbol, where the allocated value is one of a plurality of values, and where each value corresponds to a respective one of the non-memory resource instances. After allocation, the linker generates an amount of executable code, where the API instructions in the code: 1) are for using the allocated value to generate an address of a register in the appropriate non-memory resource instance, and 2) are for accessing the register.

Abstract: A processor includes a hash register and a hash generating circuit. The hash generating circuit includes a novel programmable nonlinearizing function circuit as well as a modulo-2 multiplier, a first modulo-2 summer, a modulor-2 divider, and a second modulo-2 summer. The nonlinearizing function circuit receives a hash value from the hash register and performs a programmable nonlinearizing function, thereby generating a modified version of the hash value. In one example, the nonlinearizing function circuit includes a plurality of separately enableable S-box circuits. The multiplier multiplies the input data by a programmable multiplier value, thereby generating a product value. The first summer sums a first portion of the product value with the modified hash value. The divider divides the resulting sum by a fixed divisor value, thereby generating a remainder value. The second summer sums the remainder value and the second portion of the input data, thereby generating a hash result.

Abstract: A processor includes a hash register and a hash generating circuit. The hash generating circuit includes a novel programmable nonlinearizing function circuit as well as a modulo-2 multiplier, a first modulo-2 summer, a modulor-2 divider, and a second modulo-2 summer. The nonlinearizing function circuit receives a hash value from the hash register and performs a programmable nonlinearizing function, thereby generating a modified version of the hash value. In one example, the nonlinearizing function circuit includes a plurality of separately enableable S-box circuits. The multiplier multiplies the input data by a programmable multiplier value, thereby generating a product value. The first summer sums a first portion of the product value with the modified hash value. The divider divides the resulting sum by a fixed divisor value, thereby generating a remainder value. The second summer sums the remainder value and the second portion of the input data, thereby generating a hash result.

Abstract: A reconfigurable, scalable and flexible island-based network flow processor integrated circuit architecture includes a plurality of rectangular islands of identical shape and size. The islands are disposed in rows, and a configurable mesh command/push/pull data bus extends through all the islands. The integrated circuit includes first SerDes I/O blocks, an ingress MAC island that converts incoming symbols into packets, an ingress NBI island that analyzes packets and generates ingress packet descriptors, a microengine (ME) island that receives ingress packet descriptors and headers from the ingress NBI and analyzes the headers, a memory unit (MU) island that receives payloads from the ingress NBI and performs lookup operations and stores payloads, an egress NBI island that receives the header portions and the payload portions and egress descriptors and performs egress scheduling, and an egress MAC island that outputs packets to second SerDes I/O blocks.

Abstract: A novel declare instruction can be used in source code to declare a sub-pool of resource instances to be taken from the resource instances of a larger declared pool. Using such declare instructions, a hierarchy of pools and sub-pools can be declared. A novel allocate instruction can then be used in the source code to instruct a novel linker to make resource instance allocations from a desired pool or a desired sub-pool of the hierarchy. After compilation, the declare and allocate instructions appear in the object code. The linker uses the declare and allocate instructions in the object code to set up the hierarchy of pools and to make the indicated allocations of resource instances to symbols. After resource allocation, the linker replaces instances of a symbol in the object code with the address of the allocated resource instance, thereby generating executable code.

Abstract: A pipelined run-to-completion processor executes a conditional skip instruction. If a predicate condition as specified by a predicate code field of the skip instruction is true, then the skip instruction causes execution of a number of instructions following the skip instruction to be “skipped”. The number of instructions to be skipped is specified by a skip count field of the skip instruction. In some examples, the skip instruction includes a “flag don't touch” bit. If this bit is set, then neither the skip instruction nor any of the skipped instructions can change the values of the flags. Both the skip instruction and following instructions to be skipped are decoded one by one in sequence and pass through the processor pipeline, but the execution stage is prevented from carrying out the instruction operation of a following instruction if the predicate condition of the skip instruction was true.