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In this paper, we propose an energy-efficient reconfigurable platform for in-memory processing based on novel four-terminal spin Hall effect-driven domain wall motion devices that could be employed as both nonvolatile memory cell and in-memory logic unit. The proposed designs lead to unity of memory and logic. The device to system level simulation results show that, with 28% area increase in memory structure, the proposed in-memory processing platform achieves a write energy ~15.6 fJ/bit with 79% reduction compared to that of SOT-MRAM counterpart while keeping the identical 1 ns writing speed. In addition, the proposed in-memory logic scheme improves the operating energy by 61.3%, as compared with the recent nonvolatile in-memory logic designs. An extensive reliability analysis is also performed over the proposed circuits. We employ advanced encryption standard (AES) algorithm as a case study to elucidate the efficiency of the proposed platform at application level. Simulation results exhibit that the proposed platform can show up to 75.7% and 30.4% lower energy consumption compared to CMOS-ASIC and recent pipelined domain wall (DW) AES implementations, respectively. In addition, the AES energy-delay product can show 15.1% and 6.1% improvements compared to the DW-AES and CMOS-ASIC implementations, respectively. [ABSTRACT FROM AUTHOR]

In modern many-core architectures, advanced on-chip networks provide the means of communication for the cores. This greatly complicates the design and verification of the cache coherence protocols deployed by those cores. A common approach to deal with this complexity is to decompose the whole system into the protocol and the network. This decomposition is, however, not always possible. For example, unexpected deadlocks can emerge when a deadlock-free protocol and a deadlock-free network are combined. This paper proposes a compositional methodology: prove properties over a network, prove properties over a protocol, and infer properties over the system as a whole. Our methodology is based on theorems that show that such decomposition is possible by having sufficiently large local buffers at the cores. We apply this methodology to verify several protocols such as MI, MSI, MESI and MEUSI running on top of advanced interconnects with adaptive routing. [ABSTRACT FROM AUTHOR]

Fault-tolerant minimal routing algorithms aim at finding a Manhattan path between the source and destination nodes and route around all faulty nodes. Additionally, some non-faulty nodes that are helpless to make up of a fault-tolerant minimal path should also be routed around. How to label such non-faulty nodes efficiently is a major challenge. State-of-the-art solutions could not address it very well. We propose a path-counter method. It can label every node that are helpless to make up of a fault-tolerant minimal path with low time complexity. By counter the number of fault-tolerant minimal paths, it can: support arbitrary fault distribution, check the existence of fault-tolerant minimal paths, not sacrifice any available fault-tolerant minimal paths. [ABSTRACT FROM AUTHOR]

This paper proposes a highly scalable sensor design for late transition detection in FPGA based platforms. Transition delays occur because of aging mechanisms such as Biased Temperature Instability (BTI) and Hot Carrier Injection (HCI). We propose a sensor clock (SCLK) that is a function of minimum slack time of a set of paths selected for age monitoring. There will be one such clock for many sensors as are needed in an entire FPGA. Our proposed sensor architecture makes it possible for a single SCLK to be shared by all sensors. Additionally, the proposed sensor occupies one slice (basic FPGA logic block), which leads to low area, power, and performance overhead. Using Artix-7-based board, experimental results demonstrate that the proposed aging sensor detects aging earlier than existing sensors and provides less power and performance overheads. [ABSTRACT FROM AUTHOR]

3D ICs can take advantage of a scalable communication platform, commonly referred to as the Networks-on-Chip (NoC). In the basic form of 3D-NoC, all routers are vertically connected. Partially connected 3D-NoC has emerged because of physical limitations of using vertical links. Routing is of great importance in such partially connected architectures. A high-performance, fault-tolerant and adaptive routing strategy with respect to the communication flow among the cores is crucial while freedom from livelock and deadlock has to be guaranteed. In this paper we introduce a new routing algorithm for partially connected 3D-NoCs. The routing algorithm is adaptive and tolerates the faults on vertical links as compared to the predesigned routing algorithms. Our results show a $40-50\%$ improvement in the fraction of intact inter-level communications when the fault tolerant algorithm is used. This routing algorithm is light-weight and has only one virtual channel along the $Y$ dimension. [ABSTRACT FROM AUTHOR]

Recently, Through-Silicon-Via (TSV) has been more popular to provide faster inter-layer communication in three-dimensional Networks-on-Chip (3D NoCs). However, the area overhead of TSVs reduces wafer utilization and yield which impact design of 3D architectures using a large number of TSVs such as homogeneous 3D NoCs topologies. Also, 3D routers require more memory and thus they are more power hungry than conventional 2D routers. Alternatively, hybrid 3D NoCs combine both the area and performance benefits of 2D and 3D router architectures by using a limited number of TSVs. Existing hybrid architectures suffer from higher packet delays as they do not consider the dynamic communication patterns of different application and their NoC resource usage. We propose a novel algorithm to systematically generate hybrid 3D NoC topologies for a given application such that the vertical connections are minimized while the NoC performance is not sacrificed. The proposed algorithm analyses the target application and generates hybrid architectures by efficiently redistributing the vertical links and buffer spaces based on their utilizations. Furthermore, the algorithm has been evaluated with synthetic and various real-world traffic patterns. Experimental results show that the proposed algorithm generates optimized architectures with lower energy consumption and a significant reduction in packet delay compared to the existing solutions. [ABSTRACT FROM PUBLISHER]

TSV-to-TSV coupling is known to be a significant detriment to signal integrity in three-dimensional (3D) IC architectures. Designing a reliable Through-Silicon Via is critical in order to support better performance. This paper explores the challenges brought on by capacitive and inductive TSV-to-TSV coupling in TSV-based 3D ICs. Based on our analyses, we propose two approaches to mitigate these effects. In one approach, a novel coding technique that adjusts the current flow pattern is proposed to mitigate the inductive coupling effects. In another approach an alternative architecture, wrapping around the TSVs, is proposed to greatly reduce the capacitive coupling effect. The efficiency of the proposed coding methods and supporting architectures is demonstrated by comprehensive simulations at both the hardware and system levels. [ABSTRACT FROM AUTHOR]