ETM Trace Data Acquisition and Decoding Issues for Sub-16 Byte Traces Before Program Break

ETM Trace Data Acquisition and Decoding Issues for Sub-16 Byte Traces Before Program Break

Understanding ETM Trace Data Flush Behavior in Cortex-M33 The Embedded Trace Macrocell (ETM) in ARM Cortex-M33 processors is a powerful tool for real-time instruction and data tracing, enabling developers to capture and analyze program execution flow. However, a critical issue arises when the trace data generated just before a program break is less than 16…

Cortex-R5F Hangs on IRQ Reception Without Exception Entry

Cortex-R5F Hangs on IRQ Reception Without Exception Entry

Cortex-R5F IRQ Handling Failure Leading to System Hang The Cortex-R5F processor, a member of ARM’s Cortex-R series, is designed for real-time applications requiring high reliability and deterministic behavior. However, in certain configurations, particularly when interfacing with interrupt controllers like the GIC (Generic Interrupt Controller) and peripherals such as the TTC (Triple Timer Counter) on Xilinx…

Optimizing Data Layout and Loading Strategies for ARM Neon MMLA Instructions

Optimizing Data Layout and Loading Strategies for ARM Neon MMLA Instructions

ARM Neon MMLA Instructions and Their Data Layout Challenges The ARM Neon Matrix Multiply-Accumulate (MMLA) instructions, such as SMMLA, are powerful tools for accelerating matrix operations in embedded systems. These instructions are designed to perform signed 8-bit integer matrix multiplications, specifically multiplying a 2×8 matrix by an 8×2 matrix to produce a 2×2 matrix of…

ARM Cortex-A53 Alignment Faults Due to Q Register Usage in LDR Instructions

ARM Cortex-A53 Alignment Faults Due to Q Register Usage in LDR Instructions

ARM Cortex-A53 Alignment Faults During Single Float Load Operations When working with the ARM Cortex-A53 processor, a common issue arises when the compiler generates ldr q0, [x1, #0] instructions for single float load operations, such as scratch_in[0] = Fin_r[0 * in_step];. This instruction attempts to load a 128-bit value into the Q register (Q0) from…

Cortex-A9 Multi-Core Boot Sequence and L2 Cache Initialization

Cortex-A9 Multi-Core Boot Sequence and L2 Cache Initialization

Cortex-A9 Multi-Core Boot Sequence and Cache Coherency Challenges The Cortex-A9 processor, particularly in its multi-core (MP) configuration, presents unique challenges during the boot sequence, especially when dealing with cache initialization and coherency across multiple cores. The primary concern revolves around the timing and sequence of enabling the L2 cache (L2C-310) in a multi-core environment. The…

Cortex-R52+ Asynchronous External Abort During Write Operations

Cortex-R52+ Asynchronous External Abort During Write Operations

Cortex-R52+ Asynchronous External Abort: Understanding the DFSR 0xA11 Error The Cortex-R52+ processor is a high-performance, real-time capable core designed for safety-critical applications. However, like any complex system, it can encounter issues that require deep architectural understanding to diagnose and resolve. One such issue is the occurrence of an asynchronous external abort during write operations, indicated…

ARM FVP DRAM Size Configuration Issue and Resolution

ARM FVP DRAM Size Configuration Issue and Resolution

ARM FVP DRAM Size Configuration Failure When working with ARM Fixed Virtual Platforms (FVPs), one of the critical tasks is configuring the total compute DRAM size to match the requirements of the target application or system. A common issue arises when attempting to set the DRAM size using the -C board.dram_size parameter, only to find…

AXI Protocol Peripheral Attribute Execution Order and Guarantees

AXI Protocol Peripheral Attribute Execution Order and Guarantees

AXI Protocol Peripheral Attribute Execution Order Ambiguity The Advanced eXtensible Interface (AXI) protocol is a widely adopted on-chip communication standard for high-performance embedded systems, particularly in ARM-based architectures. One of the critical aspects of the AXI protocol is its handling of transaction ordering, which ensures data consistency and predictable behavior across different system components. However,…

AXI Protocol: Write Data Storage During Outstanding Transactions Before Write Address

AXI Protocol: Write Data Storage During Outstanding Transactions Before Write Address

Write Data Storage Mechanisms in AXI Protocol During Outstanding Transactions The Advanced eXtensible Interface (AXI) protocol, widely used in ARM-based systems, is designed to handle high-performance data transfers between masters and slaves. One of the key features of AXI is its ability to support outstanding transactions, where data can be sent before the corresponding address….

Distributing Single SPI to Multiple PEs Concurrently in GIC-600

Distributing Single SPI to Multiple PEs Concurrently in GIC-600

ARM Cortex-A55 and GIC-600: SPI Interrupt Distribution Challenges in AMP Systems In systems utilizing the ARM Cortex-A55 cores alongside the GIC-600 interrupt controller, a common challenge arises when attempting to distribute a single Shared Peripheral Interrupt (SPI) to multiple Processing Elements (PEs) concurrently. This scenario is particularly relevant in Asymmetric Multiprocessing (AMP) systems, where one…