摘要:
A method includes providing an effective address, providing an address space identifier which identifies a currently executing process, providing a mapping modifier to form a modified address space identifier where the mapping modifier is based on at least one external signal generated outside the processor, using the effective address and the modified address space identifier to form a logical address, and providing a physical address corresponding to the logical address. When the effective address has a first effective address value, the address space identifier has a first address space identifier value, and the mapping modifier has a first mapping value, the physical address has a first physical address value. When the effective address has the first effective address value, the address space identifier has the first address space identifier value, and the mapping modifier has a second mapping value, the physical address has a second physical address value.
摘要:
In a processor having an address translation table, a method includes providing a logical address and control signal. When the control signal has a first value, a first physical address is provided corresponding to the logical address, and when the control signal has a second value, a second physical address is provided. The first physical address and the second physical address are stored in at least one valid entry of the address translation table. In one case, the first physical address is stored in a first valid entry having a tag field which matches the logical address and the second physical address is stored in a second valid entry having a tag field which matches the logical address. Alternatively, the first physical address is stored in a first field of a first valid entry and the second physical address is stored in a second field of the first valid entry.
摘要:
A bus master may selectively retract a currently pending access based on one or more characteristics of the currently pending access. In this manner, bus master may better control its access requests. The one or more characteristics may include, for example, type of access (e.g. read/write, instruction/data, burst/non-burst, etc.), sequence or order of accesses, address being accessed (e.g. which address range is being accessed or which device is beings accessed), the bus master requesting retraction (in an, e.g., multimaster system), or any combination thereof. A bus arbiter may also selectively retract currently pending access requests in favor of a subsequent access request based on one or more characteristics of the currently pending access request or the subsequent access request. These characteristics may include any of those listed above, priorities of the requesting masters (e.g. a priority delta between requesting masters), other attributes of the requesting masters, or any combination thereof.
摘要:
A data processing system (10) has a debug module (26) that selectively generates one or more debug messages that are specific to a Direct Memory Access (DMA) controller device (16) in the system. A control register(70) enables which of the DMA debug messages are provided. The beginning and end of DMA transfer activity is provided including when minor loop iterations start and complete. Latency information indicating system latency between a channel request and actual initiation of the request for each DMA transfer may also be included in a debug message. One of the debug messages provides periodic status of a predetermined DMA channel under control of a control register (80). At least one of the debug messages implements a watchpoint function, such as indicating when a transfer starts or ends. The debug module may be centralized in the system or distributed among each of predetermined system units.
摘要:
An arbitration control circuit (11) for arbitrating access to a slave device (4) by a plurality of master devices (2, 3) includes an undefined length burst (ULB) arbitration logic circuit (12). The ULB arbitration logic circuit (12) includes a counter (26) and a control register (24). The control register (24) stores a predetermined value. During a ULB access of the slave device (4), the counter (26) is loaded with the predetermined value and is decremented for each beat of the undefined length burst access. Arbitration access beats during the undefined length burst access.
摘要:
Various load and store instructions may be used to transfer multiple vector elements between registers in a register file and memory. A cnt parameter may be used to indicate a total number of elements to be transferred to or from memory, and an rcnt parameter may be used to indicate a maximum number of vector elements that may be transferred to or from a single register within a register file. Also, the instructions may use a variety of different addressing modes. The memory element size may be specified independently from the register element size such that source and destination sizes may differ within an instruction. With some instructions, a vector stream may be initiated and conditionally enqueued or dequeued. Truncation or rounding fields may be provided such that source data elements may be truncated or rounded when transferred. Also, source data elements may be sign- or unsigned- extended when transferred.
摘要:
Various load and store instructions may be used to transfer multiple vector elements between registers in a register file and memory. A cnt parameter may be used to indicate a total number of elements to be transferred to or from memory, and an rcnt parameter may be used to indicate a maximum number of vector elements that may be transferred to or from a single register within a register file. Also, the instructions may use a variety of different addressing modes. The memory element size may be specified independently from the register element size such that source and destination sizes may differ within an instruction. With some instructions, a vector stream may be initiated and conditionally enqueued or dequeued. Truncation or rounding fields may be provided such that source data elements may be truncated or rounded when transferred. Also, source data elements may be sign- or unsigned-extended when transferred.
摘要:
In a multi-way cache, a method for selecting N ways available for replacement includes providing a plurality of rulesets where each one of the plurality of rulesets specifies N ways in the cache that are available for replacement (where N is equal to or greater than zero). The method further includes receiving an access address, and using at least a portion of the access address to select one of the plurality of rulesets. The selected one of the plurality of rulesets may then be used to select N ways in that cache that are available for replacement. One embodiment uses the high order bits of the access address to select a ruleset. An alternate embodiment uses at least a portion of the access address and a ruleset selector control register to select the ruleset. Yet another embodiment uses the access address and address range comparators to select the ruleset.
摘要:
A set associative cache includes a plurality of sets, where each set has a plurality of ways. The set associative cache has a plurality of replacement pointers where each set of the plurality of sets has a corresponding replacement pointer within the plurality of replacement pointers, and the corresponding replacement pointer indicates a way of the set. A cache command is provided which specifies a set of the plurality of sets and which specifies a replacement way value. In response to the cache command, a current way value of the replacement pointer corresponding to the specified set is replaced with the replacement way value. The cache may further include way locking control circuitry which indicates whether or not one or more ways is locked. By indicating a locked way with the replacement way value, a locked way can be overridden and thus be used for a subsequent cache line fill.
摘要:
In one embodiment, an integrated circuit which uses one or more re-useable modules may use a signature generated by a duplicate state machine or an unmodified state machine to select, control, or otherwise affect a resource on the integrated circuit, where affecting the resource was not part of the original design and state diagram of the unmodified state machine. In one embodiment, a method and apparatus is provided for dynamically reconfiguring a plurality of test circuits in re-useable modules on an IC without modifying the controller state machine in the re-usable module.