ARM Cortex-M33 INVPC Hardfault During Context Restoration in FreeRTOS The ARM Cortex-M33 processor, with its TrustZone security extension, introduces a layer of complexity when running real-time operating systems like FreeRTOS, especially in non-secure mode. A common issue that arises is the occurrence of a forced hardfault with the INVPC (Invalid PC Load) exception during the…
GICv2 Interrupt Configuration and CPU Interface Issues The core issue revolves around the ARM Generic Interrupt Controller version 2 (GICv2) not forwarding a configured interrupt to the CPU, despite the interrupt being enabled, pending, and correctly prioritized in the GIC Distributor and CPU Interface. The problem manifests in a scenario where the GICv2 is configured…
ARM Cortex-M4 HardFault Triggered by arm_fir_q15 Function The issue at hand involves a HardFault exception being triggered on an ARM Cortex-M4 processor when executing the arm_fir_q15 function from the CMSIS DSP library. The function is part of a Finite Impulse Response (FIR) filter implementation, specifically designed for Q15 fixed-point arithmetic. The HardFault occurs during the…
NEON Intrinsics Performance Bottlenecks in ARM Cortex-A53 The ARM Cortex-A53 is a widely used processor core in embedded systems, known for its power efficiency and performance in mid-range applications. When optimizing code for the Cortex-A53, particularly when using NEON intrinsics for SIMD (Single Instruction, Multiple Data) operations, developers often encounter performance bottlenecks that are not…
ARM Cortex-M4 Thumb2 Instruction Fault During Dynamic Linking with GCC The issue at hand involves a fault occurring during the execution of a dynamically linked function on an ARM Cortex-M4 processor. The fault manifests as an INVSTATE exception, which is triggered when the processor attempts to execute a Thumb2 instruction with an invalid Execution Program…
Cortex-M7 Unaligned Access Faults During LDM/STM/LDRD/STRD Operations The Cortex-M7 processor, based on the Armv7-M architecture, is a high-performance microcontroller core designed for embedded systems requiring significant computational power. One of its key features is the Memory Protection Unit (MPU) and the Tightly Coupled Memory (TCM) architecture, which enables low-latency access to critical data. However, the…
ARM Cortex-M3 Testbench Simulation Fails to Display "TEST PASSED" Statement When working with ARM Cortex-M3 testbenches, particularly in academic or research settings, one common issue that arises is the failure to display the "TEST PASSED" statement during simulation. This issue is often encountered when using simulation tools like Modelsim, where the simulation runs without errors…
ARM Cortex-M3 Hard Fault Triggered by USART Receive Interrupt The core issue revolves around a hard fault occurring in an STM32F101RF microcontroller during the execution of a USART receive interrupt service routine (ISR). The hard fault is triggered when the program attempts to read data from the USART Data Register (DR) within the ISR. The…
AHB5 Prot to AXI Cache Signal Mapping Challenges The mapping of AHB5 protocol signals to AXI cache attributes is a critical aspect of ensuring proper communication and data integrity between AHB and AXI-based systems. The AHB5 protocol, used in many ARM-based systems, defines a set of protection and cacheability signals (hprot) that must be correctly…
Understanding Unaligned AXI Transfers and Slave Support Requirements Unaligned transfers in the AXI (Advanced eXtensible Interface) protocol refer to data transactions where the starting address of a burst transfer is not aligned to the natural boundary of the data size being transferred. For example, a 32-bit (4-byte) transfer starting at address 0x01 is unaligned because…