Abstract: An embodiment involves secure memory implementation for secure execution of virtual machines. Data is processed in a first mode and a second mode, and commands are sent to a chip interconnect bus using real addresses, wherein the chip interconnect bus includes a number of bits for the real addresses. A memory controller is operatively coupled to a memory component. A secure memory range is specified by using range registers. If the real address is detected to be in the secure memory range to match a memory component address, a real address bit is set. If the real address is in the memory address hole, a security access violation is detected. If the real address is not in the secure address range and the real address bit is set, the security access violation is detected.

Abstract: An array processor includes a managing element having a load streaming unit coupled to multiple processing elements. The load streaming unit provides input data portions to each of a first subset of the processing elements and also receives output data from each of a second subset of the processing elements based on a comparatively sorted combination of the input data portions provided to the first subset of processing elements. Furthermore, each of processing elements is configurable by the managing element to compare input data portions received from either the load streaming unit or two or more of the other processing elements, wherein the input data portions are stored for processing in respective queues. Each processing unit is further configurable to select an input data portion to be output data based on the comparison, and in response to selecting the input data portion, remove a queue entry corresponding to the selected input data portion.

Abstract: A memory system comprises a memory device coupled to a memory controller, the memory controller for receiving one or more memory requests from one or more core devices via an interconnect bus. The memory controller tracks utilization of the interconnect bus by tracking a selection of the one or more memory requests with fetched data from the one or more memory devices and waiting for scheduling to return on the interconnect bus during a time window. The memory controller, responsive to detecting utilization of the interconnect bus during the time window reaches a memory utilization threshold, dynamically selects a reduced read data size for a size of the fetched data to be returned with at least one read request from among the selection of one or more memory requests, the reduced data size selected from among at least two read data size options for the at least one read request of a maximum read data size and the reduced read data size that is less than the maximum read data size.

Abstract: Techniques for improving the security of nonvolatile memory such as magnetic random access memory (MRAM) are provided. In one aspect, a method of operating a nonvolatile memory chip is provided. The method includes: overwriting data stored on the nonvolatile memory chip automatically upon the nonvolatile memory chip being powered on. For example, all bits in the nonvolatile memory chip can be written to either i) a predetermined data state (e.g., a logic 1 or a logic 0) or ii) a random data state. A system is also provided that includes: a nonvolatile memory chip; and a writing circuit configured to overwrite data stored on the nonvolatile memory chip automatically upon the nonvolatile memory chip being powered on.

Abstract: A multiprocessor data processing system includes multiple vertical cache hierarchies supporting a plurality of processor cores, a system memory, and a system interconnect. In response to a load-and-reserve request from a first processor core, a first cache memory supporting the first processor core issues on the system interconnect a memory access request for a target cache line of the load-and-reserve request. Responsive to the memory access request and prior to receiving a systemwide coherence response for the memory access request, the first cache memory receives from a second cache memory in a second vertical cache hierarchy by cache-to-cache intervention the target cache line and an early indication of the systemwide coherence response for the memory access request. In response to the early indication and prior to receiving the systemwide coherence response, the first cache memory initiating processing to update the target cache line in the first cache memory.

Abstract: Techniques for improving the security of nonvolatile memory such as magnetic random access memory (MRAM) are provided. In one aspect, a method of operating a nonvolatile memory chip is provided. The method includes: overwriting data stored on the nonvolatile memory chip automatically upon the nonvolatile memory chip being powered on. For example, all bits in the nonvolatile memory chip can be written to either i) a predetermined data state (e.g., a logic 1 or a logic 0) or ii) a random data state. A system is also provided that includes: a nonvolatile memory chip; and a writing circuit configured to overwrite data stored on the nonvolatile memory chip automatically upon the nonvolatile memory chip being powered on.

Abstract: A data processing system includes a processor core having a store-in lower level cache, a memory controller, a memory-mapped device, and an interconnect fabric communicatively coupling the lower level cache and the memory-mapped device. In response to a first instruction in the processor core, a copy-type request specifying a source real address is transmitted to the lower level cache. In response to a second instruction in the processor core, a paste-type request specifying a destination real address associated with the memory-mapped device is transmitted to the lower level cache. In response to receipt of the copy-type request, the lower level cache copies a data granule from a storage location specified by the source real address into a non-architected buffer. In response to receipt of the paste-type request, the lower level cache issues on the interconnect fabric a command that writes the data granule from the non-architected buffer to the memory-mapped device.

Abstract: A multiprocessor data processing system includes multiple vertical cache hierarchies supporting a plurality of processor cores, a system memory, and a system interconnect coupled to the system memory and the multiple vertical cache hierarchies. A first cache memory in a first vertical cache hierarchy issues on the system interconnect a request for a target cache line. Responsive to the request and prior to receiving a systemwide coherence response for the request, the first cache memory receives from a second cache memory in a second vertical cache hierarchy by cache-to-cache intervention the target cache line and an early indication of the systemwide coherence response for the request. In response to the early indication of the systemwide coherence response and prior to receiving the systemwide coherence response, the first cache memory initiates processing to install the target cache line in the first cache memory.

Abstract: An array processor includes a managing element having a load streaming unit coupled to multiple processing elements. The load streaming unit provides input data portions to each of a first subset of the processing elements and also receives output data from each of a second subset of the processing elements based on a comparatively sorted combination of the input data portions provided to the first subset of processing elements. Furthermore, each of processing elements is configurable by the managing element to compare input data portions received from either the load streaming unit or two or more of the other processing elements, wherein the input data portions are stored for processing in respective queues. Each processing unit is further configurable to select an input data portion to be output data based on the comparison, and in response to selecting the input data portion, remove a queue entry corresponding to the selected input data portion.

Abstract: A processor core of a data processing system, in response to a first instruction, generates a copy-type request specifying a source real address and transmits it to a lower level cache. In response to a second instruction, the processor core generates a paste-type request specifying a destination real address associated with a memory-mapped device and transmits it to the lower level cache. In response to receipt of the copy-type request, the lower level cache copies a data granule from a storage location specified by the source real address into a non-architected buffer. In response to receipt of the paste-type request, the lower level cache issues a command to write the data granule from the non-architected buffer to the memory-mapped device. In response to receipt from the memory-mapped device of a busy response, the processor core abandons the memory move instruction sequence and performs alternative processing.

Abstract: Managing lowest point of coherency (LPC) memory using a service layer adapter, the adapter coupled to a processor and an accelerator on a host computing system, the processor configured for symmetric multi-processing, including receiving, by the adapter, a memory access instruction from the accelerator; retrieving, by the adapter, a real address for the memory access instruction; determining, using base address registers on the adapter, that the real address targets the LPC memory, wherein the base address registers direct memory access requests between the LPC memory and other memory locations on the host computing system; and sending, by the adapter, the memory access instruction and the real address to a media controller for the LPC memory, wherein the media controller for the LPC memory is attached to the adapter via a memory interface.

Abstract: A memory system comprises a memory device coupled to a memory controller, the memory controller for receiving one or more memory requests from one or more core devices via an interconnect bus. The memory controller tracks utilization of the interconnect bus by tracking a selection of the one or more memory requests with fetched data from the one or more memory devices and waiting for scheduling to return on the interconnect bus during a time window. The memory controller, responsive to detecting utilization of the interconnect bus during the time window reaches a memory utilization threshold, dynamically selects a reduced read data size for a size of the fetched data to be returned with at least one read request from among the selection of one or more memory requests, the reduced data size selected from among at least two read data size options for the at least one read request of a maximum read data size and the reduced read data size that is less than the maximum read data size.

Abstract: In one embodiment, a set-associative cache memory has a plurality of congruence classes each including multiple entries for storing cache lines of data. The cache memory includes a bank of counters, which includes a respective one of a plurality of counters for each cache line stored in the plurality of congruence classes. The cache memory selects victim cache lines for eviction from the cache memory by reference to counter values of counters within the bank of counters. A dynamic distribution of counter values of counters within the bank of counters is determined. In response, an amount counter values of counters within the bank of counters are adjusted on a cache miss is adjusted based on the dynamic distribution of the counter values.

Abstract: A set-associative cache memory includes a bank of counters including a respective one of a plurality of counters for each cache line stored in a plurality of congruence classes of the cache memory. Prior to receiving a memory access request that maps to a particular congruence class of the cache memory, the cache memory pre-selects a first victim cache line stored in a particular entry of a particular congruence class for eviction based on at least a counter value of the victim cache line. In response to receiving a memory access request that maps to the particular congruence class and that misses, the cache memory evicts the pre-selected first victim cache line from the particular entry, installs a new cache line in the particular entry, and pre-selects a second victim cache line from the particular congruence class based on at least a counter value of the second victim cache line.

Abstract: A set-associative cache memory includes a bank of counters including a respective one of a plurality of counters for each cache line stored in a plurality of congruence classes of the cache memory. Prior to receiving a memory access request that maps to a particular congruence class of the cache memory, the cache memory pre-selects a first victim cache line stored in a particular entry of a particular congruence class for eviction based on at least a counter value of the victim cache line. In response to receiving a memory access request that maps to the particular congruence class and that misses, the cache memory evicts the pre-selected first victim cache line from the particular entry, installs a new cache line in the particular entry, and pre-selects a second victim cache line from the particular congruence class based on at least a counter value of the second victim cache line.

Abstract: In one embodiment, a set-associative cache memory has a plurality of congruence classes each including multiple entries for storing cache lines of data. The cache memory includes a bank of counters, which includes a respective one of a plurality of counters for each cache line stored in the plurality of congruence classes. The cache memory selects victim cache lines for eviction from the cache memory by reference to counter values of counters within the bank of counters. A dynamic distribution of counter values of counters within the bank of counters is determined. In response, an amount counter values of counters within the bank of counters are adjusted on a cache miss is adjusted based on the dynamic distribution of the counter values.

Abstract: A serial communication system includes a transmitting circuit for serially transmitting data via a serial communication link including N channels where N is an integer greater than 1. The transmitting circuit includes an input buffer having storage for input data frames each including M bytes forming N segments of M/N contiguous bytes. The transmitting circuit additionally includes a reordering circuit coupled to the input buffer. The reordering circuit includes a reorder buffer including multiple entries. The reordering circuit buffers, in each of multiple entries of the reorder buffer, a byte in a common byte position in each of the N segments of an input data frame. The reordering circuit sequentially outputs the contents of the entries of the reorder buffer via the N channels of the serial communication link.

Abstract: An integrated circuit includes a transmitting circuit configured to be coupled to a physical serial interface having a bit width. The transmitting circuit is configured to transmit, via the physical serial interface, a frame including multiple aligned flits all of an equal fixed length that is an integer multiple of the bit width of the physical serial interface. The multiple flits include both a control flit specifying at least a command to be performed by a recipient of the command and a data flit providing data to be operated upon through performance of the command. The control flit includes a data protection code computed over the control flit and a data flit of a previously transmitted frame.

Abstract: A method for sorting data in an array processor. Each of a first tier of processing elements in the array processor receives data inputs from a load streaming unit. Each of the first tier processing elements compares input data portions received from the load streaming unit, wherein the input data portions are stored for processing in respective queues. The first tier processing elements select one of the input data portions to be an output data portion based on the comparison, and in response to the selection, remove a corresponding queue entry and request next input data from the load streaming unit. Each of the first tier processing elements further provides the output data portion as an input data portion to a second tier processing element that generates output data based on a comparison of output data received from at least two first tier processing elements.

Abstract: In at least some embodiments, a processor core generates a store operation by executing a store instruction in an instruction sequence. The store operation is marked as a high priority store operation in response to the store instruction being marked as high priority and is not so marked otherwise. The store operation is buffered in a store queue associated with a cache memory of the processor core. Handling of the store operation in the store queue is expedited in response to the store operation being marked as a high priority store operation and not expedited otherwise.