Architectures and Processors

ARM Cortex-M3 Exclusive Access Failing on AXI and AHB-Lite Buses The core issue revolves around the incorrect behavior of exclusive access instructions (LDREX/STREX) on an ARM Cortex-M3-based SoC design. The design integrates a Cortex-M3 processor with a custom AHB-Lite to AXI3 bridge, similar to the Xilinx DesignStart platform. The processor boots correctly and executes instructions,…

Understanding HN-F Port Attachment in CCN-502 for PMU Event Selection The CCN-502 interconnect is a critical component in ARM-based SoCs, enabling high-performance communication between various system components such as CPUs, GPUs, and memory controllers. One of the key features of the CCN-502 is its ability to profile system performance using Performance Monitoring Units (PMUs) and…

ARM Cortex-A Series SoC Requirements for Android Compatibility When designing an embedded device with a small display that leverages Android for Human-Machine Interface (HMI) applications, the selection of an appropriate System-on-Chip (SoC) is critical. Android, as an operating system, imposes specific hardware requirements that must be met to ensure smooth operation. The Android Open Source…

AMBA 5 CHI Streaming Ordered WriteUnique Transaction Flow and Coherency Issues The AMBA 5 CHI protocol introduces a sophisticated mechanism for handling streaming ordered WriteUnique transactions, which ensures that writes to a specific address are observed in the correct order by all requesters in the system. This mechanism is critical for maintaining coherency in multi-master…

ARM Thumb State Execution Efficiency and Code Density Advantages The ARM architecture provides two primary instruction sets: the ARM state, which executes 32-bit instructions, and the Thumb state, which executes 16-bit instructions. The Thumb state was introduced to address the need for higher code density and improved performance in embedded systems, where memory footprint and…

MSBuild Path Mismatch in System Canvas During Cortex-M3 Project Build The core issue revolves around a mismatch in the MSBuild path configuration when attempting to build a Cortex-M3 "hello world" project using ARM Fast Models and System Canvas. The user encounters a build failure due to System Canvas referencing an incorrect MSBuild path, specifically pointing…

Increasing AXI4 Data Bus Width Without Bandwidth Improvement The core issue revolves around attempting to increase the bandwidth of an AXI4 bus by modifying the data bus width from 32-bit to 64-bit in a RISC-V processor implementation. The primary misconception here is that merely increasing the data bus width does not inherently result in higher…

AXI4 Protocol Constraints for 32-bit Data Bus Width The AXI4 protocol, as part of the ARM AMBA specification, defines a robust framework for data transfer between components in a system-on-chip (SoC). When dealing with a 32-bit data bus width, the protocol imposes specific constraints that must be carefully considered to ensure efficient and correct data…

Fast Model Socket Example 3010 Error: DHCP Failure on FVP_MPS2_M7 The Fast Model socket example error 3010, indicating DHCP failure during the connect() operation, is a critical issue that arises when running the sockets example on the Fast Models simulator, specifically with the FVP_MPS2_M7 target. This error is particularly perplexing because the same example runs…

ARM CHI Requester Node: DataSepResp and RespSepData Order Ambiguity In the ARM Coherent Hub Interface (CHI) protocol, the handling of separated responses, specifically DataSepResp and RespSepData, at the Requester Node can lead to ambiguity in system behavior. The CHI protocol allows for the separation of data and response messages to optimize bandwidth utilization and reduce…