Advanced Micro Devices Corporation

Shrikanth Ganapathy

John Kalamatianos

Nuwan S Jayasena

Shaizeen Dilawarhusen Aga

Sudhanva Gurumurthi

Vilas K Sridharan

Michael Ignatowski

Shomit N Das

Matthew J Tomei

Yasuko Eckert

Anthony T Gutierrez

Steven E Raasch

Vedula Venkata Srikant Bharadwaj

Ross Voigt La Fetra

Karthik Ramu Sangaiah

Apostolos Kokolis

A memory module includes one or more programmable ECC engines that may be programed by a host processing element with a particular ECC implementation. As used herein, the term 'ECC implementation' refers to ECC functionality for performing error detection and subsequent processing, for example using the results of the error detection to perform error correction and to encode corrupted data that cannot be corrected, etc. The approach allows an SoC designer or company to program and reprogram ECC engines in memory modules in a secure manner without having to disclose the particular ECC implementations used by the ECC engines to memory vendors or third parties.

Error detection and correction in memory modules using programmable ECC engines

A processor includes a controller and plurality of chiplets, each chiplet including a plurality of processor cores. The controller provides chiplet-level performance information for the chiplets that identifies a performance of each chiplet at each of a plurality of performance levels for specified sets of processor cores on that chiplet. The controller receives an identification of one or more selected chiplets from among the plurality of chiplets for which a specified number of processor cores are to be configured at a given performance level, the one or more selected chiplets having been selected based on the chiplet-level performance information and performance requirements. The controller configures the specified number of processor cores of the one or more selected chiplets at the given performance level. A task is then run on the specified number of processor cores of the one or more selected chiplets at the given performance level.

Chiplet-level performance information for configuring chiplets in a processor

Methods and processing devices are provided for error protection to support instruction replay for executing idempotent instructions at a processing in memory PIM device. The processing apparatus includes a PIM device configured to execute an idempotent instruction. The processing apparatus also includes a processor, in communication with the PIM device, configured to issue the idempotent instruction to the PIM device for execution at the PIM device and reissue the idempotent instruction to the PIM device when one of execution of the idempotent instruction at the PIM device results in an error and a predetermined latency period expires from when the idempotent instruction is issued.

Method and apparatus to support instruction replay for executing idempotent code in dependent processing in memory devices

Systems, apparatuses, and methods for implementing masked fault detection for reliable low voltage cache operation are disclosed. A processor includes a cache that can operate at a relatively low voltage level to conserve power. However, at low voltage levels, the cache is more likely to suffer from bit errors. To mitigate the bit errors occurring in cache lines at low voltage levels, the cache employs a strategy to uncover masked faults during runtime accesses to data by actual software applications. For example, on the first read of a given cache line, the data of the given cache line is inverted and written back to the same data array entry. Also, the error correction bits are regenerated for the inverted data. On a second read of the given cache line, if the fault population of the given cache line changes, then the given cache line's error protection level is updated.

Masked fault detection for reliable low voltage cache operation

Providing host-based error detection capabilities in a remote execution device is disclosed. A remote execution device performs a host-offloaded operation that modifies a block of data stored in memory. Metadata is generated locally for the modified of block of data such that the local metadata generation emulates host-based metadata generation. Stored metadata for the block of data is updated with the locally generated metadata for the modified portion of the block of data. When the host performs an integrity check on the modified block of data using the updated metadata, the host does not distinguish between metadata generated by the host and metadata generated in the remote execution device.

Providing host-based error detection capabilities in a remote execution device

A technique for accessing a memory having a high latency portion and a low latency portion is provided. The technique includes detecting a promotion trigger to promote data from the high latency portion to the low latency portion, in response to the promotion trigger, copying cache lines associated with the promotion trigger from the high latency portion to the low latency portion, and in response to a read request, providing data from either or both of the high latency portion or the low latency portion, based on a state associated with data in the high latency portion and the low latency portion.

Latency hiding for caches

A computing device having a cache memory that is configured in a write-back mode is described. A cache controller in the cache memory acquires, from a record of bit errors that are present in each of a plurality of portions of the cache memory, a number of bit errors in a portion of the cache memory. The cache controller detects a coherency state of data stored in the portion of the cache memory. Based on the coherency state and the number of bit errors, the cache controller selects an error protection from among a plurality of error protections. The cache controller uses the selected error protection to protect the data stored in the portion of the cache memory from errors.

Bit error protection in cache memories

A method of operating a cache in a computing device includes, in response to receiving a memory access request at the cache, determining compressibility of data specified by the request, selecting in the cache a destination portion for storing the data based on the compressibility of the data and a persistent fault history of the destination portion, and storing a compressed copy of the data in a non-faulted subportion of the destination portion, wherein the persistent fault history indicates that the non-faulted subportion excludes any persistent faults.

Method and apparatus for using compression to improve performance of low voltage caches

Systems, apparatuses, and methods for reliably transmitting data over voltage scaled links are disclosed. A computing system includes at least first and second devices connected via a link. In one implementation, if a data block can be compressed to less than or equal to half the original size of the data block, then the data block is compressed and sent on the link in a single clock cycle rather than two clock cycles. If the data block cannot be compressed to half the original size, but if the data block can be compressed enough to include error correction code (ECC) bits without exceeding the original size, then ECC bits are added to the compressed block which is sent on the link at a reduced voltage. The ECC bits help to correct for any errors that are generated as a result of operating the link at the reduced voltage.

Reliable voltage scaled links for compressed data

A computing device having a cache memory (or 'cache') is described, as is a method for operating the cache. The method for operating the cache includes maintaining, in a history record, a representation of a number of bit errors detected in a portion of the cache. When the history record indicates that no bit errors or a single-bit bit error was detected in the portion of the cache memory, the method includes selecting, based on the history record, an error protection to be used for the portion of the cache memory. When the history record indicates that a multi-bit bit error was detected in the portion of the cache memory, the method includes disabling the portion of the cache memory.

Growing community of inventors

Santa Clara, CA, United States of America

Shrikanth Ganapathy