Ampere Computing LLC

Sandeep Brahmadathan

Nagi Aboulenein

Massimo Sutera

Kha Minh Huynh

Danh La

Stephan Jourdan

Jared Eric Bendt

Rakesh Kumar

Brian Thomas Chase

James Edward Casteel

Vung Thanh Huynh

Kedar Karandikar

Anil Kumar Handenahalli Rajanna

Apparatus and methods for extending functionality of memory controllers using a loopback mode for testing are disclosed herein. In one aspect, a processor-based device provides a memory access intercept circuit configured to receive a memory write request that is directed to and received by a memory controller. The memory access intercept circuit transmits proxy write data to the memory controller, and intercepts write data directed to the memory controller for the memory write request. The memory access intercept circuit stores the write data in a write data buffer, and, upon intercepting the proxy write data from the memory controller directed to a physical (PHY) interface circuit, retrieves the write data from the write data buffer and transmits the write data to the PHY interface circuit. The memory access intercept circuit subsequently receives, from the PHY interface circuit, loopback data, and stores the loopback data in a read data buffer.

Extending functionality of memory controllers using a loopback mode for testing in a processor-based device

Methods and systems for an advanced initialization bus (AIB) are presented. In an aspect, an AIB master sends, to an AIB slave, a serial clock over a first signal line, and performs a read operation with the AIB slave. Performing the read operation comprises sending a read command to the AIB slave via a bus comprising at least one bidirectional input/output (I/O) channel, each I/O channel having its own respective signal line, sending a read address to the AIB slave via the bus, receiving a copy of the serial clock from the AIB slave over a second signal line, and latching read data provided by the AIB slave via the bus into a read buffer using the copy of the serial clock as a data strobe. Thus, the AIB master latches the read data provided by the AIB slave using a read strobe also provided by the AIB slave.

Advanced initialization bus (AIB)

A memory control circuit stores codewords in a memory module configured to limit errors to one wire of a memory interface. A codeword includes a first block with a first data portion and a second block with a second data portion. An error correction code symbol in the second block is used to locate and correct errors in the second block. Some bits of the first block are repurposed as metadata. The remaining bits are used as parity bits for detecting errors in the first block. The second block is merged with the first block before being stored to memory and demerged from the first block in a memory read operation. Demerging causes errors in the first block to create errors in a corresponding location in the second block. The location of errors found in the second block is used to locate and correct parity errors in the first block.

Parity protected memory blocks merged with error correction code (ECC) protected blocks in a codeword for increased memory utilization

A component die validation built-in self-test (VBIST) engine is presented. In an aspect, a component die includes component circuitry for performing a component function, interface circuitry for communicating with another die, and a VBIST circuit. The VBIST circuit includes a traffic generator that generates test data streams, a tracker that receives and validates test data streams, and a configurable switching matrix for coupling the traffic generator to at least one of the component circuitry, the interface circuitry, or the tracker, and for coupling at least one of the component circuitry, the interface circuitry, or the traffic generator to the tracker. The VBIST circuit can send traffic to and from the component circuitry directly, or indirectly via the interface circuitry in loopback mode, and can be used for memory initialization and test.

Component die validation built-in self-test (VBIST) engine

A codeword read from memory includes data blocks including data and supplemental blocks including error correction code (ECC) symbols for detecting and correcting data errors. Metadata can be stored in the supplemental blocks to increase memory utilization but using bits of the supplemental blocks for metadata leaves too few bits remaining for the ECC symbols. To maintain error protection, the supplemental blocks include ECC symbols to protect a first data portion of the codeword and parity bits configured to protect a second data portion of the codeword. Errors in the first data portion can be located and corrected using the ECC symbols. Errors in the second data portion can be detected by the parity. For example, the first data portion is encoded based on the second data portion, so locations of parity errors correspond to locations of symbol errors, and parity errors can be corrected.

Integrated error correction code (ECC) and parity protection in memory control circuits for increased memory utilization

Apparatus and methods for extending functionality of memory controllers in a processor-based device are disclosed herein. In one aspect, a processor-based device provides a memory access intercept circuit that is communicatively coupled to a memory controller and a memory device. The memory access intercept circuit is configured to receive a memory write request that is directed to and received by the memory controller, and generates a write transaction identifier (ID) for the memory write request. The memory access intercept circuit then generates proxy write data containing the write transaction ID, and sends the proxy write data to the memory controller. The memory access intercept circuit subsequently intercepts the actual write data directed to the memory controller, and stores the write data in a write data buffer in association with the write transaction ID.

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Dublin, CA, United States of America

Sandeep Brahmadathan