1. Telangana train accident: Goods train derails near Peddapalli. Check full list of cancelled, diverted trains today | Today News  Mint
2. Goods train derails in Telangana's Peddapalli; 20 trains cancelled, 10 diverted  The Economic Times
3. 11 coaches of goods train derail in Telangana  The Times of India
4. Goods train derailment in Telangana affects rail traffic between Delhi and Chennai  Telangana Today
5. Goods train derails in Telangana's Peddapalli; 30 trains cancelled, several diverted  The Hindu

1. BREAKING| 'Bulldozer Reminds Of Lawlessness' : Supreme Court Says Properties Can't Be Demolished Merely...  Live Law - Indian Legal News
2. "Officials To Pay From Salary": Top Court Guidelines On 'Bulldozer Justice'  NDTV
3. ‘Heavens won’t fall on authorities if they hold their hands for some period’: SC sets pan India guidelines against bulldozer action  The Financial Express
4. Executive Can't Become Judge, Pronounce Guilt Of Persons & Punish Them By Demolishing Their Properties :...  Live Law - Indian Legal News
5. ‘Officials will pay for demolitions from their salary’: 5 Key SC observations on ‘chilling’ side of ‘bulldozer justice’  Mint

According to the latest rumors, the Samsung Galaxy Z Flip FE could be powered by the Exynos 2400 chipset which is surprising.

The post Samsung Galaxy Z Flip FE chipset of choice could surprise you appeared first on Phandroid.

Samsung is running some Black Friday deals for its foldables like the Galaxy Z Fold 6 and Flip 6, so what are you waiting for?

The post Grab the Samsung Galaxy Z Fold 6 and Flip 6 at incredible Black Friday prices! appeared first on Phandroid.

If you’re in the market for a new Android tablet, check out these early Black Friday deals for the Samsung Galaxy Tab S10 series.

The post Check out these Samsung Galaxy Tab S10 early Black Friday deals and SAVE BIG! appeared first on Phandroid.

Samsung has an early Black Friday deal for its accessories and wearables, so don’t miss out if you want some savings!

The post INCREDIBLE early Black Friday deal saves you on Samsung wearables and accessories! appeared first on Phandroid.

In a unique online romance scam, a man in Tianjin, China, fell victim to a bizarre "marriage bed burning" ritual, costing him Rs 11 lakh.

Shared by Gator Boys star Paul Bedard, the viral video shows the alligator emerging from his den to the tune of the iconic song.

Kapil Sharma wasted no time in diving into their personal stories, focusing on how Deepinder met his Mexican wife.

Positioned near the side of her head, the eye provides an expansive field of vision, while a thick layer of protective blubber shields it from harm and maintains warmth.

The $20 Merry Multiplier scratch-off ticket she chose turned out to be a $250,000 top prize winner.

A Bengaluru-based entrepreneur recently took to social media to jokingly explain how his daily commute on bike taxes in the city doubles as an unexpected fitness routine.

The prankster claims that as many as seven schools fell prey to his prank and made the hats.

The couple, together for nine years, had announced the wedding date in January and were eagerly looking forward to their long-awaited special day.

The post has sparked a heated debate about Bengaluru's rising rental prices and the need for a cap on deposits.

The post details a highly restrictive environment where employees are forbidden from basic actions like looking away from their screens or using their phones.

Vesper, the maker of piezoelectric sensors used in microphone production and winner of CES Innovation Award 2018 raised a $23M Series B round. American Family Ventures led the investment with participation from Accomplice, Amazon Alexa Fund, Baidu, Bose Ventures, Hyperplane, Sands Capital, Shure, Synaptics, ZZ Capital and some undisclosed investors.

Vesper’s innovative sensors can be used in consumer electronics like TV remote controls, smart speakers, smartphones, intelligent sensor nodes, and hearables. The company will use the funding proceeds to scale-up its functions like mass production of its microphones and support expanded research and development, hiring, and establishing international sales offices.

The main product of Vesper is VM1000, a low noise, high range,single-ended analog output piezoelectric MEMS microphone. It consists of a piezoelectric sensor and circuitry to buffer and amplify the output.

The hot-selling product of Vesper is VM1010 with ZeroPower Listening which is the first MEMS microphone that enables voice activation to battery-powered consumer devices.

The unique selling point of Vesper’s products is they are built to operate in rugged environments that have dust and moisture.

"Vesper's ZeroPower Listening capabilities coupled with its ability to withstand water, dust, oil, and particulate contaminants enables users that have never before been possible," said Katelyn Johnson, principal of American Family Ventures. "We are excited about Vesper's quest to transform our connected world, including IoT devices."

Other recent funding news include $24 raised by sensor-based baby sock maker Owlet, IFTTT banks $24M from Salesforce to scale its IoT Enterprise offering, and Intel sells its Wind River Software to TPG.

Siemens Building Technologies division announced it will acquire Enlighted Inc., a smart IoT building technology provider. The transaction is expected to close in Q3’18.

Enlighted Inc.’s core element is an advanced lighting control application. It is based on a patented, software-defined smart sensor that collects and monitors real-time occupancy, light levels, temperatures and energy usage.

The sensor can gauge temperature, light level, motion, energy, and has Bluetooth connectivity.

The Enlighted system works by collecting temperature, light and motion data via its smart sensors. A gateway device carries the information to Energy Manager, a secure browser-based interface to create profiles and adjust settings of the entire Enlighted Advanced Lighting Control System. The Energy manager operates as an analytics device.

The whole system consists of multi-function sensors, distributed computing, a network, and software applications run by Enlighted Inc.

Enlighted Inc.’s main target market is commercial real estate. Key use cases of its intelligent Lighting Control System are energy efficiency, controlling heating, ventilation and air conditioning, and building utilization reports.

Use the Postscapes 'Connected Products Framework' to understand the smart home and buildings eco-system.

[SAPS] Office of the Provincial Commissioner KwaZulu-Natal

[SAPS] - A former company Director (57) is expected to appear in the Thabamoopo Magistrates Court in Lebowakgomo on 11 November 2024 for allegedly defrauding a pensioner an amount of R378 000.00 in the name of business.

[SAPS] - Polokwane based Hawks Serious Commercial Crime Investigation in collaboration with National Traffic Anti-corruption Unit arrested 11 suspects between the ages of 27 and 57 for alleged fraud at various Provinces during operation "SISFIKILE".

[SAPS] - Gqeberha Flying Squad members clamped down on criminals involved in illegal abalone activities and robbery suspects in two unrelated incidents.

[SAPS] - Five suspects are appearing in the Kariega Magistrate's Court today, after they were arrested and found in possession of cycads with an estimated value of R1 Million on Friday 08 November 2024.

[SAPS] One hundred and seventy one (171) murder suspects, 261 attempted murder suspects and 250 suspected rapists were among 12 593 suspects who were arrested during various operations by police in KwaZulu-Natal in the month of October. During such operations police also managed to recover 345 firearms and 2 998 rounds of ammunition of various calibre of firearms. Among the recovered firearms were 23 rifles and 17 homemade illegal guns.

[SAnews.gov.za] Twenty-three people in Gauteng have died as a result of food borne-related poisoning after consuming food from spaza shops.

[SAnews.gov.za] With the United Nations Framework Convention on Climate Change (COP29) taking place this week, South Africa expects the COP29 Presidency to enhance efforts to finalise the New Collective Quantified Goal on Finance (NCQG), which is a matter of great importance for developing economies.

[Daily Maverick] Water and Sanitation Minister Pemmy Majodina held an urgent meeting on Sunday with Gauteng Premier Panyaza Lesufi and Johannesburg Mayor Dada Morero to address severe water shortages affecting Johannesburg communities.

[allAfrica]

[Parliament of South Africa] Parliament, Tuesday, 12 November 2024 - The National Assembly (NA) will hold a plenary session scheduled to start at 10:00. Among the items on the agenda from 10:00 to 13:00 is the statement by the Minister of Water and Sanitation on water security in the country and a debate on 16 Days of Activism for no violence against women and children. The debate will be held under the theme, "Marking 30 years of democratic rights for women and fostering national unity to end gender-based violence".

[The Conversation Africa] Despite the flaws in the latest novel by South African writer Nthikeng Mohlele, there is something alluring about Revolutionaries' House. It is Mohlele's most political novel, and the parallels drawn between love and politics - and their pitfalls - are intriguing.

[DA] It is a national embarrassment that the inability of the City of Johannesburg to supply water to its residents, business and public sector offices, has now led to the shutdown of operations at the Constitutional Court, on Constitution Hill in Braamfontein.

[GroundUp] The education department says there's only one SETA official assisting all nine provinces

The market is trending towards integrating and stacking multiple chiplets into a single package to meet the growing demands of speed, connectivity, and intelligence.  However, designing and signing off chiplets and packages individually is time-...(read more)

In the rapidly evolving landscape of automotive electronics, traditional monolithic design approaches are giving way to something more flexible and powerful—chiplets. These modular microchips, which are themselves parts of a whole silicon system, offer unparalleled potential for improving system performance, reducing manufacturing costs, and accelerating time-to-market in the automotive sector. However, the transition to working with chiplets in automotive electronics is not without its challenges.

Designers must now grapple with a new set of considerations, such as die-to-die interconnect standards, complex processes, and the integration of diverse IPs. Advanced toolsets and standardized design approaches are required to meet these challenges head-on and elevate the potential of chiplets in automotive innovation. In the following discourse, we will explore in detail the significance of chiplets in the context of automotive electronics, the obstacles designers face when working with this paradigm, and how Cadence comprehensive suite of IPs, tools, and flows is pioneering solutions to streamline the chiplet design process.

Unveiling Chiplets in Automotive Electronics

For automotive electronics, chiplets offer a methodology to modularize complex functionalities, integrate different chiplets into a package, and significantly enhance scalability and manufacturability. By breaking down semiconductor designs into a collection of chiplets, each fulfilling specific functions, automotive manufacturers can mix and match chiplets to rapidly prototype new designs, update existing ones, and specialize for the myriad of use cases found in vehicles today.

The increasing significance of chiplets in automotive electronics comes as a response to several industry-impacting phenomena. The most obvious among these is the physical restriction of Moore's Law, as large die sizes lead to poor yields and escalating production costs. Chiplets with localized process specialization can offer superior functionality at a more digestible cost, maintaining a growth trajectory where monolithic designs cannot. Furthermore, chiplets support the assembly of disparate technologies onto a single subsystem, providing a comprehensive yet adaptive solution to the diverse demands present in modern vehicles, such as central computing units, advanced driver-assistance systems (ADAS), infotainment units, and in-vehicle networks. This chiplet-based approach to functional integration in automotive electronics necessitates intricate design, optimization, and validation strategies across multiple domains.

The Complexity Within Chiplets

Yet, with the promise of chiplets comes a series of intricate design challenges. Chiplets necessitate working across multiple substrates and technologies, rendering the once-familiar 2-dimensional design space into the complex reality of multi-layered, sometimes even three-dimensional domains. The intricacies embedded within this design modality mandate devoting considerable attention to partitioning trade-offs, signal integrity across multiple substrates, thermal behavior of stacked dies, and the emergence of new assembly design kits to complement process design kits (PDKs).

To effectively address these complexities, designers must wield sophisticated tools that facilitate co-design, co-analysis, and the creation of a robust virtual platform for architectural exploration. Standardizations like the Universal Chip Interconnect Express (UCIe) have been influential, providing a die-to-die interconnect foundation for chiplets that is both standardized and automotive-ready. The availability of UCIe PHY and controller IP from Cadence and other leading developers further eases the integration of chiplets in automotive designs.

The Role of Foundries and Packaging in Chiplets

Foundries have also pivoted their services to become a vital part of the chiplet process, providing specialized design kits that cater to the unique requirements of chiplets. In tandem, packaging has morphed from being a mere logistical afterthought to a value-added aspect of chiplets. Organizations now look to packaging to deliver enhanced performance, reduced power consumption, and the integrity required by the diverse range of technologies encompassed in a single chip or package. This shift requires advanced multiscale design and analysis strategies that resonate across a spectrum of design domains.

Tooling Up for Chiplets with Cadence

Cadence exemplifies the rise of comprehensive tooling and workflows to facilitate chiplet-based automotive electronics design. Their integrations address the challenges that chiplet-based SoCs present, ensuring a seamless design process from the initial concept to production. The Cadence suite of tools is tailored to work across design domains, ensuring coherence and efficiency at every step of the chiplet integration process.

For instance, Cadence Virtuoso RF subflows have become critical in navigating radio frequency (RF) challenges within the chiplets, while tools such as the Integrity 3D-IC Platform and the Allegro Advanced Multi-Die Package Design Solution have surfaced to enable comprehensive multi-die package designs. The Integrity Signal Planner extends its capabilities into the chiplet ecosystem, providing a centralized platform where system-wide signal integrity can be proactively managed. Sigrity and Celsius, on the other hand, offer universally applicable solutions that take on the challenges of chiplets in signal integrity and thermal considerations, irrespective of the design domain. Each of these integrated analysis solutions underscores the intricate symphony between technology, design, and packaging essential in unlocking the potential of chiplets for automotive electronics.

Cadence portfolio includes solutions for system analysis, optimization, and signoff to complement these domain-specific tools, ensuring that the challenges of chiplet designs don't halt progress toward innovative automotive electronics. Cadence enables designers to engage in power- and thermal-aware design practices through their toolset, a necessity as automotive systems become increasingly sophisticated and power-efficient.

A Standardized Approach to Success with Chiplets

Cadence’s support for UCIe underscores the criticality of standardized approaches for heterogeneous integration by conforming to UCIe standards, which numerous industry stakeholders back. By co-chairing the UCIe Automotive working group, Cadence ensures that automotive designs have a universal and standardized Die-to-Die (D2D) high-speed interface through which chiplets can intercommunicate, unleashing the true potential of modular design.

Furthermore, Cadence champions the utilization of virtual platforms by providing transaction-level models (TLMs) for their UCIe D2D IP to simulate the interaction between chiplets at a higher level of abstraction. Moreover, individual chiplets can be simulated within a chiplet-based SoC context leveraging virtual platforms. Utilizing UVM or SCE-MI methodologies, TLMs, and virtual platforms serve as first lines of defense in identifying and addressing issues early in the design process before physical silicon even enters the picture.

Navigating With the Right Tools

The road to chiplet-driven automotive electronics is one paved with complexity, but with a commitment to standards, it is a path that promises significant rewards. By leveraging Cadence UCIe Design and Verification IP, tools, and methodologies, automotive designers are empowered to chart a course toward chiplets and help to establish a chiplet ecosystem. With challenges ranging from die-to-die interconnect to standardization, heterogeneous integration, and advanced packaging, the need for a seamless integrated flow and highly automated design approaches has never been more apparent. Companies like Cadence are tackling these challenges, providing the key technology for automotive designers seeking to utilize chiplets for the next-generation E/E architecture of vehicular technology.

In summary, chiplets have the potential to revolutionize the automotive electronics industry, breathing new life into the way vehicles are designed, manufactured, and operated. By understanding the significance of chiplets and addressing the challenges they present, automotive electronics is poised for a paradigm shift—one that combines the art of human ingenuity with the power of modular and scalable microchips to shape a future that is not only efficient but truly intelligent.

Learn more about how Cadence can help to enable automakers and OEMs with various aspects of automotive design.

We live in a rapidly growing “digitalized world,” with an ever-increasing need for video/music streaming, gaming, AI/machine learning, etc. All of these propel demand on modern SoC design to quickly evolve the SoC by fitting more sophisti...(read more)

The automotive industry is currently on the cusp of a radical evolution, steering towards a future where cars are not just vehicles but sophisticated, software-defined vehicles (SDV). This shift is marked by an increased reliance on automation and a significant increase in the use of sensors to improve safety and reliability. However, the increasing number of sensors has led to higher compute demands and poses challenges in managing a wide variety of data. The traditional method of using separate processors to manage each sensor's data is becoming obsolete. The current trends necessitate a unified processing system that can deal with multimodal sensor data, utilizing traditional Digital Signal Processing (DSP) and AI-driven algorithms. This approach allows for more efficient and reliable sensor fusion, significantly enhancing vehicle perception. Developers often face difficulties adhering to stringent power, performance, area, and cost (PPAC) and timing constraints while designing automotive SoCs.

Cadence, with its groundbreaking products and AI-powered processors, is enabling designers and automotive manufacturers to meet the future sensor fusion demands within the automotive sector. At the recent CadenceLive Silicon Valley 2024, Amol Borkar, product marketing director at Cadence, showcased the company's dedication and forward-thinking solutions in a captivating presentation titled "Addressing Tomorrow’s Sensor Fusion Needs in Automotive Computing with Cadence." This blog aims to encapsulate the pivotal takeaways from the presentation. If you missed the chance to watch this presentation live, please click here to watch it.

Significant Trends in the Automotive Market – Industry Landscape

We are witnessing a revolution in automotive technology. Innovations like occupant and driver monitoring systems (OMS, DMS), 4D radar imaging, LiDAR technology, and 360-degree view are pushing the boundaries of what's possible, leading us into an era of remarkable autonomy levels—ranging from no feet or hands required to eventually no eyes needed on the road.

Sensor Fusion and Increasing Processing Demands—Sensor fusion effectively integrates data from different sensors to help vehicles understand their surroundings better. Its main benefit is in overcoming the limitations of individual sensors. For example, cameras provide detailed visual information but struggle in low-light or lousy weather. On the other hand, radar is excellent at detecting objects in these conditions but lacks the detail that cameras provide. By combining the data from multiple sensors, automotive computing can take advantage of their strengths while compensating for their weaknesses, resulting in a more reliable and robust system overall.

One thing to note is that the increased number of sensors produces various data types, leading to more pre-processing.

On-Device Processing—As the industry moves towards autonomy, there is an increasing need for on-device data processing instead of cloud computing to enable vehicles to make informed decisions. Embracing on-device processing is a significant advancement for facilitating real-time decisions and avoiding round-trip latency.

AI Adoption—AI has become integral to automotive applications, driving safety, efficiency, and user experience advancements. AI models offer superior performance and adaptability, making future-proofing a crucial consideration for automotive manufacturers. AI significantly enhances sensor fusion algorithms, offering scalability and adaptability beyond traditional rule-based approaches. Neural networks enable various fusion techniques, such as early fusion, late fusion, and mid-fusion, to optimize the integration and processing of sensor data.

Future Sensor Fusion Needs

Automotive architectures are continually evolving. With current trends and AI integration into radar and sensor fusion applications, SoCs should be modular, flexible, and programmable to meet market demands.

Heterogeneous Architecture- Today's vehicles are loaded with various sensors, each with a unique processing requirement. Running the application on the most suitable processor is essential to achieve the best PPA. To meet such requirements, modern automotive solutions require a heterogeneous compute approach, integrating domain-specific digital signal processors (DSPs), neural processing units (NPUs), central processing unit (CPU) clusters, graphics processing unit (GPU) clusters, and hardware accelerator blocks. A balanced heterogeneous architecture gives the best PPA solution.

Flexibility and Programmability- The industry has come a long way from using computer vision algorithms such as HOG (Histogram Oriented Gradient) to detect people and objects, HAR classifier to detect faces, etc., to CNN and LSTM-based AI to Transformer models and graphical neural networks (GNN). AI has evolved tremendously over the last ten years and continues to evolve. To keep up with the evolving rate of AI, SoC design must be flexible and programmable for updates if needed in the future.

Addressing the Sensor Fusion Needs with Cadence

Cadence offers a complete suite of hardware and software products to address the increasing compute requirements in automotive. The comprehensive portfolio of Tensilica products built on the robust 32-bit RISC architecture caters to various automotive CPU and AI needs. What makes them particularly appealing is their scalability, flexibility, and configurability, offering many options to meet diverse needs.

The Xtensa family of products offers high-quality, power-efficient CPUs. Tensilica family also includes AI processors like Neo NPUs for the best power, performance, and area (PPA) for AI inference on devices or more extensive applications. Cadence also offers domain-specific products for DSPs such as HIFI DSPs, specialized DSPs and accelerators for radar and vision-based processing, and a general-purpose family of products for floating point applications.

The ConnX family offers a wide range of DSPs, from compact and low-power to high-performance, optimized for radar, lidar, and communications applications in ADAS, autonomous driving, V2X, 5G/LTE/4G, wireless communications, drones, and robotics. Tensilica's ISO26262 certification ensures compliance with automotive safety standards, making it a trusted partner for advanced automotive solutions. The Cadence NeuroWeave Software Development Kit (SDK) provides customers with a uniform, scalable, and configurable ML interface and tooling that significantly improves time to market and better prepares them for a continuously evolving AI market. Cadence Tensilica offers an entire ecosystem of software frameworks and compilers for all programming styles.

Tensilica's comprehensive software stack supports programming for DSPs, NPUs, and accelerators using C++, OpenCL, Halide, and various neural network approaches. Middleware libraries facilitate applications such as SLAM, radar processing, and Eigen libraries, providing robust support for automotive software development.

Conclusion

Cadence’s Tensilica products offer a development toolchain and various IPs tailored for the automotive industry, covering audio, vision, radar, unified DSPs, and NPUs. With ISO certification and a robust partner ecosystem, Tensilica solutions are designed to meet the future needs of automotive computing, ensuring safety, efficiency, and innovation.

Learn More

• Cadence Automotive Solutions
• Cadence Automotive IP
• Sensor Fusion and ADAS in TSMC Automotive Processes
• Revolution on the Road: How Cadence is Driving the Future of Automotive Design!
• Taming Design Complexity in Chiplet-Based Automotive Electronics
• UCIe and Automotive Electronics: Pioneering the Chiplet Revolution

The demand for higher-performance computing is greater than ever. Cutting-edge applications in artificial intelligence (AI), big data analytics, and databases require high-speed memory systems to handle the ever-increasing volumes and complexities of data. Advancements in cloud computing and machine virtualization are stretching the limits of current capabilities. AI applications hosted in the cloud rely on fast access and reduced latency in memory systems, which is amplified by an increasing number of CPU and GPU cores.

Introducing the DDR5 Multiplexed Rank DIMM (MRDIMM), the next-generation memory module technology designed to meet the needs of high-performance computing (HPC) and AI in cloud applications. By leveraging existing DDR5 DRAM memory devices, MRDIMM modules not only double the DRAM data rate but also maintain the RAS capabilities of the industry-proven RDIMM modules, setting a new precedent for memory module performance.

Let’s compare RDIMM and MRDIMM modules using the same DRAM parts. Today, high-speed production DDR5 RDIMM modules run at 5600Mbps. Those modules use DDR5 DRAM parts, which also run at 5600Mbps. An MRDIMM module using the same DDR5 5600Mbps DRAM parts will run at a blazing 11.2Gbps.

One key metric for best-in-class performance, low bit error rate (BER), and ease of adoption is the eye diagram. The eye diagram illustrates at-speed system margin and accurately represents DDR system quality when captured with a pseudo-random binary sequence (PRBS)-like pattern. The diagram below illustrates Cadence’s 3nm silicon write eye diagram for DDR5 MRDIMM IP running at 12.8Gbps.

Cadence 3nm DDR5 MRDIMM 12.8Gbps test chip write eye diagram, design kit is available today

The eye diagram is captured using a PRBS-like pattern, incorporating a package and system board representative of a typical MRDIMM channel. Using PRBS-like patterns is crucial for capturing accurate eye diagrams. Repetitive clock-like data patterns create deceptively “open eyes” that do not reflect the real system performance. Effects like intersymbol interference, simultaneous switching, reflections, and crosstalk are not accurately reflected in the eye diagrams for parallel interfaces like DDR using non-random data streams. Relying on improperly captured eye diagrams inevitably leads to a significantly worse real system BER than conveyed by that eye diagram.

Doubling the DDR5 RDIMM data rate is challenging. Achieving high performance while optimizing for area and power requires multiple design techniques. Feed-forward equalization (FFE), decision feedback equalization (DFE), continuous-time linear equalization (CTLE), and T-coils are required to reach 12.8Gbps MRDIMM data rates in multi-channel systems. Building a production-worthy 12.8Gbps DDR5 MRDIMM IP requires engineering expertise that comes from many generations of memory interface design and production experience. Cadence has developed this expertise through multiple DDR5/4, LPDDR5X/5, and GDDR6 designs in different technology nodes and foundries. For instance, Cadence’s GDDR6 IP is available in three foundries and ten process nodes, with mass production at speeds exceeding 22Gbps.

For your next project, consider DDR5 12.8Gbps MRDIMM, a technology that not only doubles the bandwidth of DDR5 RDIMM but also promises rapid proliferation into next-generation AI, data center, HPC, and enterprise applications. With its cutting-edge capabilities, the Cadence DDR5 12.8Gbps MRDIMM IP is ready to power the future of computing.

Today's high-performance computing systems often require the designer to instantiate multiple CPU or DSP cores in their subsystem. However, the performance gained by using multiple CPUs comes with additional programming complexity, especially when accessing shared memory data structures and hardware peripherals. CPU cores need to access shared data in an atomic fashion in a multi-core environment. Locking is the most basic requirement for data sharing. A core takes the lock, accesses the shared data structure, and releases the lock. While one core has the lock, other cores are disallowed from accessing the same data structure. Typically, locking is implemented using an atomic read-modify-write bus transaction on a variable allocated in an uncached memory.

This blog shares the AXI4 locking mechanism when implementing an Xtensa LX-based multi-core system on a Xilinx FPGA platform. It uses a dual-core design mapped to a KC705 platform as an example.

Exclusive Access to Accomplish Locking

The Xtensa AXI4 manager provides atomic access using the AXI4 atomic access mechanism. While Xtensa's AXI manager interface generates an exclusive transaction, the subordinate's interface is also expected to support exclusive access, i.e., AXI monitoring. Xilinx BRAM controller's AXI subordinate interface does not support exclusive access, i.e., AXI monitoring: AXI Feature Adoption in Xilinx FPGAs.

Leveraging Xtensa AXI4 Subordinate Exclusive Access

The Xtensa LX AXI subordinate interface supports exclusive access. One approach is to utilize this support and allocate locks in one of the core's local data memories. Ensure that the number of external exclusive managers is configured, typically to the number of cores (Figure 1).

Figure 1

Note that the Xtensa NX AXI subordinate interface does not support exclusive access. For an Xtensa NX design, shared memory with AXI monitoring is required.

In Figure 2, the AXI_crossbar#2 (block in green) routes core#0's manager AXI access (blue connection) to both core's local memories. Core#1's manager AXI (yellow connection) can also access both core's local memories. Locks can be allocated in either core's local data memory.

In-Bound Access on Subordinate Interface

On inbound access, the Xtensa AXI subordinate interface expects a local memory address, i.e., an external entity needs to present the same address as the core would use to access local memory in its 4GB address space. AXI address remap IP (block in pink) translates the AXI system address to each core's local address. For example, assuming locks are allocated in core#0's local memory, core#1 generates an AXI exclusive to access a lock allocated in core#0's local memory (yellow connection). AXI_crossbar#2 forwards transaction to M03_AXI port (green connection). AXI_address_remap#1 translates the AXI system address to the local memory address before presenting it to core#0's AXI subordinate interface (pink connection).

It is possible to configure cores with disjoint local data memory addresses and avoid the need for an address remap IP block. But then it will be a heterogeneous multi-core design with a multi-image build. An address remap IP is required to keep things simple, i.e., a homogeneous multi-core with a single image build. A single image uses a single memory map. Therefore, both cores must have the same view of a lock, i.e., the lock's AXI bus address must be the same for both.

Figure 2

AXI ID Width

Note Xtensa AXI manager interface ID width=4 bits. Xtensa's AXI subordinate interface ID width=12 bits. So, you must configure AXI crossbar#2 and AXI address remap AXI ID width higher than 4. AXI IDs on a manager port are not globally defined; thus, an AXI crossbar with multiple manager ports will internally prefix the manager port index to the ID and provide this concatenated ID to the subordinate device. On return of the transaction to its manager port of origin, this ID prefix will be used to locate the manager port, and the prefix will be truncated. Therefore, the subordinate port ID is wider in bits than the manager port ID. Figure 3 shows the Xilinx crossbar IP AXI ID width configuration.

Figure 3

Software Tools Support

Cadence tools provide a way to place locks at a specific location. For more details, please refer to Cadence's Linker Support Packages (LSP) Reference Manual for Xtensa SDK. .xtos.lock(green) resides in core#0's local memory and holds user-defined and C library locks. The lock segment memory attribute is defined as shared inner (cyan) so that L32EX and S32EX instructions generate an exclusive transaction on an AXI bus. See Figure 4. The stack and per-core Xtos and C library contexts are allocated in local data memory (yellow).

…………..LSP memory map………….
BEGIN dram0
0x40000000: dataRam : dram0 : 0x8000 : writable ;
dram0_0 : C : 0x40000400 - 0x40007fff : STACK : .dram0.rodata .clib.percpu.data .rtos.percpu.data .dram0.data .clib.percpu.bss .rtos.percpu.bss .dram0.bss;
END dram0
…………………
BEGIN sysViewDataRam0
0xA0100000: system : sysViewDataRam0 : 0x8000 : writable, uncached, shared_inner;
lockRam_0 : C : 0xA0100000 - 0xA01003ff : .xtos.lock;
END sysViewDataRam0
…………..

Figure 4

Please visit the Cadence support site for more information on emulating Xtensa cores on FPGAs.

Cadence tapes out 32G UCIe interface IP for high speed, highly efficient chiplet designs and demonstrate high data rate performance in TSMC's 3nm technology(read more)