Abstract: Embodiments herein relate to a test, repair, and diagnostic solution for chip-to-chip interconnects. In one aspect, on a first chip, a first finite state machine (FSM) is coupled to a set of transmit lanes. To test each transmit lane, one at a time, the first FSM is to apply a first periodic signal to a transmit lane under test and concurrently apply a second periodic signal to other transmit lanes of the set of transmit lanes, where a phase of the first periodic signal is opposite to a phase of the second periodic signal. A comparator compares a detected signal on the lane under test to an expected response. The comparator can be on the first chip, when the first chip is tested alone, or on a second chip, where the two chips are tested together.

Abstract: Runtime memory BIST techniques are described herein. In one example, a system such as an SoC includes logic to schedule runtime testing of the memory that is non-destructive in multiple phases. Running testing of memory in multiple phases includes triggering a memory built-in self-test (BIST) testing of a subset of memory locations in a phase, where the processing logic is to pause access to the memory during the phase. The processing logic can resume access to the memory between testing phases. The next region of the memory can be tested in the phase that follows. This process can continue until the entire memory is tested, without requiring the system to be powered down.

Abstract: The disclosed embodiments relate to method, apparatus and system for testing memory circuitry and diagnostic components designed to test the memory circuitry. The memory may be tested regularly using Memory Built-In Self-Test (MBIST) to detect memory failure. Error Correction Code (ECC)/Parity is implemented for SRAM/Register Files/ROM memory structures to protect against transient and permanent faults during runtime. ECC/Parity encoder and decoder logic detect failure on both data and address buses and are intended to catch soft error or structural fault in address decoding logic in SRAM Controller, where data may be read/written from/to different locations due to faults. ECC/parity logic on the memory structures are subject to failures. In certain exemplary embodiments, an array test controller is used to generate and transmit error vectors to thereby determine faulty diagnostic components. The test vectors may be generated randomly to test the diagnostic components during run-time for in-field testing.

Abstract: A die-to-die repeater circuit includes a transmit circuit coupled to a die-to-die interconnect, the transmit circuit including at least one flip flop to function as a part of a linear feedback shift register (LFSR) to transmit a value across the die-to-die interconnect for design for test (DFT) to check proper operation of the die-to-die interconnect, and a receive circuit coupled to the die-to-die interconnect, the receive circuit including at least one flip flop to function as part of a multiple input shift register (MISR).

Abstract: A processor, including: a core; system test circuitry, the system test circuitry to be locked during operational processor operation; reset circuitry including a kick-off test (KOT) input, the reset circuitry to detect a reset with the KOT input asserted, and to initiate an in-field system test (IFST) mode; a test interface controller to receive in IFST mode an encrypted test packet having a signature, verify the signature of the test packet, and decrypt the test packet; and IFST control circuitry to cause the system test circuitry to perform an IFST test according to the decrypted test packet and to log or report results.

Abstract: A processor, including: a core; system test circuitry, the system test circuitry configured to be locked except during an in-field system test (IFST) mode; IFST control circuitry; and a test interface controller, including: a data interface to receive a test packet; a parser to parse the test packet into a key, a signature, and a stored hash-of-hashes; a decryption circuit to decrypt the signature according to the key and to generate a computed hash-of-hashes; a hash circuit to verify the stored hash-of-hashes against the computed hash-of-hashes; and an IFST interface, wherein the test interface controller is to signal the IFST control circuitry to place the system test circuitry in IFST mode.

Abstract: A die-to-die repeater circuit includes a transmit circuit coupled to a die-to-die interconnect, the transmit circuit including at least one flip flop to function as a part of a linear feedback shift register (LFSR) to transmit a value across the die-to-die interconnect for design for test (DFT) to check proper operation of the die-to-die interconnect, and a receive circuit coupled to the die-to-die interconnect, the receive circuit including at least one flip flop to function as part of a multiple input shift register (MISR).

Abstract: The disclosed embodiments relate to method, apparatus and system for testing memory circuitry and diagnostic components designed to test the memory circuitry. The memory may be tested regularly using Memory Built-In Self-Test (MBIST) to detect memory failure. Error Correction Code (ECC)/Parity is implemented for SRAM/Register Files/ROM memory structures to protect against transient and permanent faults during runtime. ECC/Parity encoder and decoder logic detect failure on both data and address buses and are intended to catch soft error or structural fault in address decoding logic in SRAM Controller, where data may be read/written from/to different locations due to faults. ECC/parity logic on the memory structures are subject to failures. In certain exemplary embodiments, an array test controller is used to generate and transmit error vectors to thereby determine faulty diagnostic components. The test vectors may be generated randomly to test the diagnostic components during run-time for in-field testing.

Abstract: A processor, including: a core; system test circuitry, the system test circuitry configured to be locked except during an in-field system test (IFST) mode; IFST control circuitry; and a test interface controller, including: a data interface to receive a test packet; a parser to parse the test packet into a key, a signature, and a stored hash-of-hashes; a decryption circuit to decrypt the signature according to the key and to generate a computed hash-of-hashes; a hash circuit to verify the stored hash-of-hashes against the computed hash-of-hashes; and an IFST interface, wherein the test interface controller is to signal the IFST control circuitry to place the system test circuitry in IFST mode.

Abstract: A processor, including: a core; system test circuitry, the system test circuitry to be locked during operational processor operation; reset circuitry including a kick-off test (KOT) input, the reset circuitry to detect a reset with the KOT input asserted, and to initiate an in-field system test (IFST) mode; a test interface controller to receive in IFST mode an encrypted test packet having a signature, verify the signature of the test packet, and decrypt the test packet; and IFST control circuitry to cause the system test circuitry to perform an IFST test according to the decrypted test packet and to log or report results.

Abstract: Methods and systems for generating data transformations to improve ROM yield and programming time. A bit flip register can be configured in association with the ROM and a binary string can be read into the bit flip register on reset. Subsequently, data output from the ROM can be selectively complemented utilizing a content of the bit flip register and the content of the bit flip register can be programmed into the ROM in order to reduce programming time for each ROM. A defective cell can be tolerated by selectively flipping a column with respect to the defective cell to improve yield. A built-in self-test (BIST) engine that generates addresses up to and including content of an address limiting register can be employed to limit the ROM access to a programmed part during testing in order to tolerate defects in any unused location.

Abstract: Methods and systems for reducing memory test time utilizing a serial per march element communicating architecture. A small number of slow speed signals can be configured between a BIST wrapper and a BIST controller to transfer information in accordance with a BIST sequence that includes a number of march elements. An information transfer protocol can be implemented between the BIST wrapper and the BIST controller to transfer Information with respect to each march element that includes a number of BIST operations, address sequencing information, and data pattern. A command register can be loaded utilizing the slow speed signals and slow speed clock and content of the command register can be decoded. An encoded BIST operation can then be executed once for each BIST operation per march element. The serial per march element communicating architecture reduces test time as a communication overhead and a requirement for high speed wires are eliminated.

Abstract: Methods and systems for generating data transformations to improve ROM yield and programming time. A bit flip register can be configured in association with the ROM and a binary string can be read into the bit flip register on reset. Subsequently, data output from the ROM can be selectively complemented utilizing a content of the bit flip register and the content of the bit flip register can be programmed into the ROM in order to reduce programming time for each ROM. A defective cell can be tolerated by selectively flipping a column with respect to the defective cell to improve yield. A built-in self-test (BIST) engine that generates addresses up to and including content of an address limiting register can be employed to limit the ROM access to a programmed part during testing in order to tolerate defects in any unused location.

Abstract: A self-test module for use in an electronic device includes a test controller and a memory. The memory is configured to receive test vectors from the test controller. A comparator is configured to receive the test data from the memory via an output data path. A strobing buffer is located in the output data path between an output from the memory and an input to the comparator. The strobing buffer is configured to selectively enable the test vectors to propagate from the memory output to the comparator input.

Abstract: A multiport latch-based memory device includes a latch array, a plurality of first multiplexers, and a second multiplexer. The latch array is responsive to output data from an input data register in a functional mode associated with the latch-based memory device. The plurality of first multiplexers is responsive to output data from the latch array in the functional mode. The plurality of first multiplexers is responsive to output data from the input data register in a test mode associated with the latch-based memory device. The second multiplexer selectively provides output data from the plurality of first multiplexers to the input data register in the test mode, thereby providing a data path bypassing the latch array in the test mode. Embodiments of a corresponding method and computer-readable medium are also provided.

Abstract: A scan cell is configured to receive first, second and third data bits at respective first, second and third data inputs. A control input is configured to receive a control signal. Latching logic is configured to latch data received at the first and second latch inputs to a scan cell output. The first latch input is configured to receive the first data bit. Selection logic is configured to select between the second and third data bits depending on a state of the control signal, and to provide the selected bit to the second latch input.

Abstract: An integrated circuit chip that supports stored-pattern (SP) logic built-in self-testing (LBIST) includes a device under test (DUT) and a test controller. System-level SP LBIST testing is performed using an external, system ATE (automated test equipment) that transmits test input data to the test controller for application to the DUT, which generates test output data that is transmitted from the test controller to the system ATE, which performs golden signature comparisons on the test output data. During system-level DUT testing, all communications between the system ATE and the chip are via a single interface, such as a conventional, serial JTAG port.

Abstract: A multiport latch-based memory device includes a latch array, a plurality of first multiplexers, and a second multiplexer. The latch array is responsive to output data from an input data register in a functional mode associated with the latch-based memory device. The plurality of first multiplexers is responsive to output data from the latch array in the functional mode. The plurality of first multiplexers is responsive to output data from the input data register in a test mode associated with the latch-based memory device. The second multiplexer selectively provides output data from the plurality of first multiplexers to the input data register in the test mode, thereby providing a data path bypassing the latch array in the test mode. Embodiments of a corresponding method and computer-readable medium are also provided.

Abstract: A path monitor, a method of monitoring a path, an integrated circuit and a library of standard logic elements. In one embodiment, the path monitor includes: (1) a delay element having an input couplable to an input of a clocked flip-flop associated with a path to be monitored and configured to provide a predetermined delay and (2) a clocked exclusive OR gate having a clock input, a first input coupled to an output of the delay element, a second input couplable to the output of the clocked flip-flop and an output at which the clocked exclusive OR gate is configured to respond to a clock signal to provide an error signal only when logic levels of the first input and the second input differ.

Abstract: A stored-pattern logic self-test system includes a memory, a device under test and a test controller. The memory stores test pattern data including test stimuli. The device under test includes a scan chain and a test access port configurable to control operation of the scan chain. The test controller is configured to test the device under test by controlling the memory to output the test stimuli to the device under test. The test controller controls the test access port to load the test stimuli into the scan chain, and receives and evaluates response data from the device under test.