Abstract:
A first cache arrangement including an input configured to receive a memory request from a second cache arrangement; a first cache memory for storing data; an output configured to provide a response to the memory request for the second cache arrangement; and a first cache controller; the first cache controller configured such that for the response to the memory request output by the output, the cache memory includes no allocation for data associated with the memory request.
Abstract:
A package includes a die and at least one further die. The die has an interface configured to receive a transaction request from the further die via an interconnect and to transmit a response to the transaction request to said further die via the interconnect. The die also has mapping circuitry which is configured to allocate to the received transaction a local source identity information as source identity information, the local source identity information comprising one of a set of reusable local source identity information. This ensures the order of transactions tagged with a same original source identity and target and allows transactions tagged with different source identifiers to be processed out of order.
Abstract:
A package includes a first die and a second die, at least one of said first and second dies being a memory. The dies are connected to each other through an interface. The interface is configured to transport a plurality of control signals. The number of control signals is greater than a width of the interface. At least one of the first and second dies performs a configurable grouping so as to provide a plurality of groups of control signals. The signals within a group are transmitted across the interface together.
Abstract:
A package includes a first die and a second die. The dies are connected to each other through an interface. The package includes interrupt processing for detecting interrupt information and providing a packet in response to the interrupt information detection. The packet includes an address to which data in the packet is to be written. The interface is configured to transport the packet between the dies. A data store is provided to which the data is writable. An interrupt event is determined from data received in several packets.
Abstract:
A package includes a first die and a second die, at least one of said first and second dies being a memory. The dies are connected to each other through an interface. The interface is configured to transport both control signals and memory transactions. A sampling circuit samples the control signals before transport on the interface. The sampling circuit is controlled in dependence on at least one quality of service parameter associated with a respective control signal.
Abstract:
A computer system comprises on-chip a CPU with at least one different module, both having circuitry to generate two types of address request packets, one being a control command packet to which a destination device must respond on receipt and the other type being an interrupt request with a priority indicator for a selective response by the destination device.
Abstract:
There is disclosed a computer system including a microprocessor on an integrated circuit chip comprising an on-chip CPU and a debugging port connected to a communication bus on the integrated circuit and to an external debugging computer device. The external debugging device is operable to transmit control signals through the debugging port: a) to stop execution by the CPU of instructions obtained from a first on-chip memory; b) to provide from a second memory associated with the external debugging computer device a debugging routine to be executed by the CPU; and c) to restart operation of the CPU after the routine with execution of instructions from an address determined by the external debugging device. The on-chip CPU is operable with code in the first memory which is independent of the debugging routine. A method of operating such a computer system with an external debugging device is also disclosed.
Abstract:
A cache coherency mechanism for a computer system having a plurality of processors, each for executing a sequence of instructions, at least one of the processors having a cache memory associated therewith. The computer system includes a memory that provides an address space where data items are stored for use by all of the processors. A behavior store holds in association with an address of each item, a cache behavior identifying the cacheable behavior of the item, the cacheable behaviors including a software coherent behavior and an automatically coherent behavior. When a cache coherency operation is instigated by a cache coherency instruction, the operation is effected dependent on the cacheable behavior associated with the specified address of the item. Methods for modifying the coherency status of a cache are also described.
Abstract:
A method and a circuit configuration for operation of a bus system. A bus includes a bus control unit which controls only an arbitration and when time is exceeded during a data transmission. An actual data transmission is determined in a respective active master unit and an addressed slave unit. A characteristic of a bus cycle, such as a data length, access to a data area or a control area and a waiting cycle, is transmitted in encoded form through a multiplicity of control lines.
Abstract:
A circuit including an initiator of a transaction, an interconnect, and a controller. The controller is configured in response to a condition in a least one first part of the circuit to send a notification via the interconnect to at least one block in a second part of the circuit. The notification includes information about the condition in the first part of the circuit, the condition preventing a response to the transaction from being received by the initiator.