ARM Cortex-M33 SAU and PPC Configuration for Non-Secure UART1 Access The ARM Musca-A1 platform, based on the ARM Cortex-M33 processor, implements a TrustZone security architecture that divides the system into Secure and Non-Secure worlds. Configuring peripherals like UART1 for Non-Secure access requires careful manipulation of the Security Attribution Unit (SAU) and the Peripheral Protection Controller…
Cortex-A72 Memory Benchmark Performance Degradation and Gradual Improvement The observed behavior in the Cortex-A72 memory benchmark, where performance gradually improves over multiple runs, is a complex interplay between the processor’s cache hierarchy, DRAM behavior, and the memory access patterns of the benchmark itself. The benchmark involves a 400MB buffer with pseudo-random memory accesses, which inherently…
ARM Cortex-A72 64-bit MADD Throughput Limitations The ARM Cortex-A72, a high-performance processor core within the ARMv8-A architecture, exhibits a significant performance discrepancy when executing 64-bit integer multiply-accumulate (MADD) instructions compared to 32-bit integer, single-precision (float), and double-precision (double) operations. Specifically, the throughput of 64-bit MADD instructions is approximately one-third that of the other data types….
ARM Cortex-A72 AArch32 Virtual-to-Physical Address Translation Challenges The ARM Cortex-A72 processor, when operating in AArch32 mode, presents a unique set of challenges when attempting to translate virtual addresses to physical addresses, particularly in user space. The Cortex-A72, part of ARM’s Cortex-A series, is a high-performance processor that supports both AArch32 and AArch64 execution states. In…
AXI Protocol Handshake Rules and Deadlock Scenarios in Multi-Transaction Sequences The AXI protocol defines strict rules for handshaking between the master and slave using the xREADY and xVALID signals to ensure data integrity and avoid deadlocks. A deadlock occurs when two or more transactions are waiting for each other to complete, resulting in a system…
ARM Cortex-A72 Debugger Hangs During NEON Vectorization and Type Casting The issue at hand involves the debugger stalling or failing to execute specific lines of code when working with ARM Cortex-A72 Aarch64 processors, particularly during NEON vectorization and type casting operations. The debugger appears to hang indefinitely when encountering instructions such as uint8x16_t aa =…
STM32H745 Dual-Core Debugging Challenges with IAR Toolchain The STM32H745 microcontroller, featuring a dual-core ARM Cortex-M7 and Cortex-M4 architecture, presents unique debugging challenges when using the IAR Embedded Workbench toolchain. The primary issue revolves around the inability to simultaneously debug both cores using separate IDE instances, despite following the recommended STMicroelectronics Application Note AN5286 for debugger…
ARMv8 TLB Miss Penalty and Table Walk Latency Overview In ARMv8 architecture, the Translation Lookaside Buffer (TLB) is a critical component for virtual-to-physical address translation. When a TLB miss occurs, the processor must perform a table walk to retrieve the necessary translation information from the page tables stored in memory. This process introduces latency, which…
ARM Cortex-M7 MPU Configuration and Privilege Mode Transition Fault The issue at hand involves an unexpected MemManage Fault on an ARM Cortex-M7 processor (specifically the STM32H7 series) when transitioning from privileged thread mode to unprivileged thread mode. The fault is triggered immediately after writing to the CONTROL register to switch to unprivileged mode, with the…
Flash Memory CRC Check Mechanism and Its Disabling in ARM Cortex-M3 The ARM Cortex-M3 microcontroller architecture incorporates a Flash Memory Cyclic Redundancy Check (CRC) mechanism to ensure data integrity during runtime. This mechanism is designed to verify the integrity of the Flash memory contents by computing a CRC value and comparing it against a precomputed…