Tutu Ajayi

dblp:204/4263 · DBLP profile ↗
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8ranked-venue papers
2as first author
4since 2021 · last 2026
0000-0001-7960-9828ORCID · corroborated

Domains — the database's venue-derived domains; a paper can count in several

Systems, architecture and hardware · 8 · 2 first-author · 4 since 2021Applied, interdisciplinary, general and emerging computing · 2 · 1 since 2021
YearPublicationVenuePosition
2026 QFEC: A 9.97 Gb/s Fully Configurable Quad-Mode Decoder for LDPC, Polar, Turbo, and Convolutional Codes
abstract
Rapidly evolving wireless channel conditions and communication standards demand adaptable forward error correction (FEC) decoders. Existing rigid architectures, designed for a single standard, exhibit limited adaptability in terms of throughput and/or coding gain, hindering the timely deployment of new applications. To overcome these limitations, we propose QFEC (quad-mode FEC decoder), a unified and highly configurable FEC decoder. QFEC enables a wide range of throughput vs. coding gain tradeoffs across QC-LDPC, Turbo, Polar, and Convolutional codes (CC) by providing full configurability for existing standards and proprietary systems. This ensures communication reliability under varying channel conditions and seamless support for both legacy and emerging communication protocols. Our hardware-unified approach leverages a shared memory and computation unit architecture that exploits the inherent commonalities in the iterative message-passing dataflow of all four code types. We attain outstanding flexibility at high data rates through an innovative combination of a fully customizable interconnect and a multi-mode computation datapath. The QFEC chip, fabricated in GF 12 nm FinFET technology, achieves 9.97 Gb/s throughput for the Optical Communication Terminal (OCT) standard and 6.52 Gb/s for 5G BG1, while consuming normalized energy efficiency (NEE) of 1.04 pJ/b and 1.53 pJ/b, respectively. This design can reach a maximum of 25.4 Gb/s using a proprietary QC-LDPC configuration. This design significantly surpasses existing solutions in flexibility by offering the broadest support for standards and parameters with a unified, efficient architecture. To the best of our knowledge, this is the first chip implementation of a fully flexible quad-mode FEC decoder for QC-LDPC, Polar, Turbo, CC codes.
Yufan Yue, Kuan-Yu Chen 0001, Xiangdong Wei, Tutu Ajayi, Hyunwon Chung, Ronald G. Dreslinski, David T. Blaauw, Hun-Seok Kim
IEEE Trans. Circuits Syst. I Regul. Pap.4
2022 Enabling Software-Defined RF Convergence with a Novel Coarse-Scale Heterogeneous Processor
abstract
RF system development is traditionally constrained by a restrictive trade-off between power efficiency and programmatic flexibility. We outline a path towards achieving both, thereby enabling a range of new system concepts that better utilize limited resources. As an example, for many future applications, we consider RF convergence – reusing the same spectrum and waveforms to achieve multiple distributed system functions and goals, simultaneously. To enable this next step in processing, we develop a novel framework that includes both software and the system-on-chip (SoC) design.
Daniel W. Bliss, Tutu Ajayi, Ali Akoglu, Ilkin Aliyev, Toygun Basaklar, Leul Belayneh, David T. Blaauw, John S. Brunhaver, Chaitali Chakrabarti, Liangliang Chang, Kuan-Yu Chen 0001, Ming-Hung Chen, Xing Chen 0004, Alex R. Chiriyath, Alhad Daftardar, Ronald G. Dreslinski, Arindam Dutta, Allen-Jasmin Farcas, Yukang Fu, A. Alper Goksoy, Xin He 0011, Md Sahil Hassan, Andrew Herschfelt, Jacob Holtom, Hun-Seok Kim, Anish Krishnakumar, Owen Ma, Joshua Mack, Saurav Mallik, Sumit K. Mandal, Radu Marculescu, Brittany M. McCall, Trevor N. Mudge, Ümit Y. Ogras, Vishrut Pandey, Saquib Ahmad Siddiqui, Yu-Hsiu Sun, Adarsh A. Venkataramani, Xiangdong Wei, Benjamin R. Willis, Hanguang Yu, Yufan Yue
ISCAS2
2022 A Unified Forward Error Correction Accelerator for Multi-Mode Turbo, LDPC, and Polar Decoding
abstract
Forward error correction (FEC) is a critical component in communication systems as the errors induced by noisy channels can be corrected using the redundancy in the coded message. This paper introduces a novel multi-mode FEC decoder accelerator that can decode Turbo, LDPC, and Polar codes using a unified architecture. The proposed design explores the similarities in these codes to enable energy efficient decoding with minimal overhead in the total area of the unified architecture. Moreover, the proposed design is highly reconfigurable to support various existing and future FEC standards including 3GPP LTE/5G, and IEEE 802.11n WiFi. Implemented in GF 12nm FinFET technology, the design occupies 8.47mm2 of chip area attaining 25% logic and 49% memory area savings compared to a collection of single-mode designs. Running at 250MHz and 0.8V, the decoder achieves per-iteration throughput and energy efficiency of 690Mb/s and 44pJ/b for Turbo; 740Mb/s and 27.4pJ/b for LDPC; and 950Mb/s and 45.8pJ/b for Polar.
Yufan Yue, Tutu Ajayi, Xueyang Liu, Peiwen Xing, David T. Blaauw, Ronald G. Dreslinski, Hun-Seok Kim
ISLPED2
2022 FASCINET: A Fully Automated Single-Board Computer Generator Using Neural Networks
abstract
Designing single-board computers (SBCs) is becoming more challenging given the growing number of discrete components that are made available and the rate at which this number grows. Keeping track of all available components options, revisions, and functionalities is challenging for SBC designers who are striving for faster design cycles. Moreover, the procedure of deciding peripheral components, their values, and connections of an SBC is not only difficult because of various parameters that need to be considered but also is time consuming as there exist numerous components on a typical SBC nowadays. In this article, an SBC generator tool, FASCINET, is presented that uses a neural network (NN) model to design customized peripheral circuits for SBCs. The tool creates a large commercial off-the-shelf database (COTS DB) of existing components, efficiently searches through them, and selects optimal components for both main and peripheral components based on the user’s requirements. Creating such a broad COTS DB requires processing abundant datasheets. A manual approach is time consuming, even if only a fraction of all available datasheets is considered. In order to automate this process, this article describes a novel NN-based approach for automatically categorizing datasheets and proposes an extraction technique for parsing relevant functional information from tables within. Our evaluation using a test set that contains over 770 000 components shows that the category of datasheets is identified correctly over 95% of the time. Additionally, the table extractor has a precision above 96%. Our proposed fully autonomous SBC design approach reduces the time for generating the schematic of an SBC to as little as 2 min. For validating the accuracy of our model, the netlists of 400 SBCs designed by FASCINET are compared to the human-designed versions. This evaluation shows that FASCINET is able to design SBCs that are identical to the manually designed ones except for minor differences.
Morteza Fayazi, Zach Colter, Zineb Benameur-El Youbi, Javad Bagherzadeh, Tutu Ajayi, Ronald G. Dreslinski
IEEE Trans. Comput. Aided Des. Integr. Circuits Syst.5
2020 Bridging Academic Open-Source EDA to Real-World Usability
abstract
Several academic EDA tools have been released; however, few are used in real tapeouts, even by other academics. Robust open-source tools require feedback and direction from users. To this end, OpenROAD employs end-users as internal design advisors who bring with them the experience of multiple tapeouts and EDA tool flow development. This paper discusses the OpenROAD design advisors' ongoing work to bring OpenROAD from a collection of tools to an end-to-end autonomous design flow. We discuss our work to fill in the gaps for a full RTL-to-GDS design flow, assemble a full-flow test suite reflective of real tapeouts, debug flow-level issues between tools, and bridge the gap between OpenROAD developers and others in the open-source community. Lastly, we discuss OpenROAD's long-term goal to become fully autonomous, and what that means from a user's perspective.
Austin Rovinski, Tutu Ajayi, Guanru Wang, Mehdi Saligane
ICCAD2
2020 An Open-source Framework for Autonomous SoC Design with Analog Block Generation
abstract
We present the world's first autonomous mixed-signal SoC framework, driven entirely by user constraints, along with a suite of automated generators for analog blocks. The process-agnostic framework takes high-level user intent as inputs to generate optimized and fully verified analog blocks using a cell-based design methodology. Our approach is highly scalable and silicon-proven by an SoC prototype which includes 2 PLLs, 3 LDOs, 1 SRAM, and 2 temperature sensors fully integrated with a processor in a 65nm CMOS process. The physical design of all blocks, including analog, is achieved using optimized synthesis and APR flows in commercially available tools. The framework is portable across different processes and requires no-human-in-the-Ioop, dramatically accelerating design time.
Tutu Ajayi, Sumanth Kamineni, Yaswanth K. Cherivirala, Morteza Fayazi, Kyumin Kwon, Mehdi Saligane, Shourya Gupta, Chien-Hen Chen, Dennis Sylvester, David T. Blaauw, Ronald G. Dreslinski, Benton H. Calhoun, David D. Wentzloff
VLSI-SOC1
2019 Toward an Open-Source Digital Flow: First Learnings from the OpenROAD Project
abstract
We describe the planned Alpha release of OpenROAD, an open-source end-to-end silicon compiler. OpenROAD will help realize the goal of "democratization of hardware design", by reducing cost, expertise, schedule and risk barriers that confront system designers today. The development of open-source, self-driving design tools is in and of itself a "moon shot" with numerous technical and cultural challenges. The open-source flow incorporates a compatible open-source set of tools that span logic synthesis, floorplanning, placement, clock tree synthesis, global routing and detailed routing. The flow also incorporates analysis and support tools for static timing analysis, parasitic extraction, power integrity analysis, and cloud deployment. We also note several observed challenges, or "lessons learned", with respect to development of open-source EDA tools and flows.
Tutu Ajayi, Vidya A. Chhabria, Mateus Fogaça, Soheil Hashemi, Abdelrahman Hosny, Andrew B. Kahng, Jeongsup Lee, Uday Mallappa, Marina Neseem, Geraldo Pradipta, Sherief Reda, Mehdi Saligane, Sachin S. Sapatnekar, Carl Sechen, Mohamed Shalan, William Swartz, Lutong Wang, Zhehong Wang, Mingyu Woo, Bangqi Xu
DAC1
2017 A carbon nanotube transistor based RISC-V processor using pass transistor logic
abstract
With silicon-based transistors approaching their scaling limits, multiple successor technologies are competing for silicon's place. Due to recent fabrication breakthroughs, one promising alternative is the carbon nanotube field-effect transistor (CNTFET), which uses carbon nanotubes as the channel medium instead of silicon. Although logic gates using CNTFETs have been demonstrated to provide up to an order of magnitude better energy-delay product (EDP) over silicon-based counterparts, system-level design using CNTFETs show significantly smaller EDP improvement because of the critical path of the design, output load capacitance and corresponding drive strengths of gates. In this paper, we address this challenge by exploring various architectural design choices using CNTFET-based pass transistor logic (PTL) and create an energy-efficient RISC-V processor. While silicon-based design traditionally prefers complementary logic over PTL, CNTFETs are ideal candidates for PTL due to their low threshold voltage, low power dissipation, and equal strength p-type and n-type transistors. By utilizing PTL to design modules that lie on the processor's critical path, systems can efficiently exploit CNTFET's potential benefits. Our results show that while a CNTFET RISC-V processor using complementary logic achieves a 2.9× EDP improvement over a silicon design, using PTL along the critical path components in the ALU can boost EDP improvement 5× as well as reduce area by 17% over 16 nm silicon CMOS.
Aporva Amarnath, Siying Feng, Subhankar Pal, Tutu Ajayi, Austin Rovinski, Ronald G. Dreslinski
ISLPED4