ARM Cortex-A72 SGI0 Interrupt Handling and Group Configuration Mismatch The issue at hand involves the failure of Software Generated Interrupts (SGIs) to trigger a second time on an ARM Cortex-A72 processor using the GIC-500v interrupt controller. The initial setup and triggering of SGIs (SGI0 to SGI15) work correctly, but subsequent attempts to trigger any SGI…
PendSV Exception and Interrupt Priority Mismanagement During Nested Interrupts The core issue revolves around the handling of the PendSV exception and nested interrupts in an ARM Cortex-M4-based system, specifically the S32K148 microcontroller. The problem manifests when a PendSV exception is intentionally generated during the execution of a lower-priority interrupt (Interrupt A) while interrupts are globally…
ARM Cortex-M7 SW-DP Mode and DPIDCODE Read Failure The ARM Cortex-M7 processor, a high-performance embedded processor based on the ARMv7-M architecture, supports both Serial Wire Debug (SWD) and JTAG debugging interfaces. SWD is a 2-pin interface that provides a compact and efficient alternative to JTAG for debugging and tracing. However, when attempting to read the…
Cortex-M7 System Address Map and AHBP Interface Behavior The Cortex-M7 processor, like other ARM Cortex-M series processors, utilizes a predefined memory map that divides the 32-bit address space into specific regions for different purposes. One of these regions, the System segment, spans from 0xE0100000 to 0xFFFFFFFF. This region is designated for vendor-specific devices and system…
AxUSER Signal Instability During VALID Assertion in AXI Transfers In the context of AMBA AXI (Advanced eXtensible Interface) protocol, the stability of control and data signals during the assertion of the VALID signal is a fundamental requirement for ensuring reliable data transfers between masters and slaves. The AxUSER signal, which carries user-defined information such as…
ARM Cortex-A72 Exception Handling During ICC_IAR1_EL1 Access at EL1 The ARM Cortex-A72 processor, part of the ARMv8-A architecture, provides a sophisticated interrupt handling mechanism through the Generic Interrupt Controller (GIC). One of the critical registers in this context is the ICC_IAR1_EL1 (Interrupt Controller Interrupt Acknowledge Register 1), which is used to acknowledge and retrieve the…
ECC Functionality in ARM Cortex-A53: Overview and Operational Context Error Correction Code (ECC) is a critical feature in modern processors, particularly in safety-critical and high-reliability systems. In the ARM Cortex-A53, ECC is implemented to detect and correct bit flips in memory, ensuring data integrity. The Cortex-A53, being a widely used core in embedded and mobile…
IWIC Clock Dependency During Sleep Mode with Q-Channel Clock Gating The ARM Cortex-M55 processor, like many modern microcontrollers, employs advanced power management techniques to minimize energy consumption during idle or low-activity periods. One such technique is clock gating, where the clock signal to specific modules or the entire processor is temporarily halted to save power….
ARM Cortex-A Series: TTBR Update and TLB Invalidation Synchronization When working with ARM architectures, particularly the Cortex-A series, one of the most critical operations is the modification of the Translation Table Base Register (TTBR) and the subsequent invalidation of the Translation Lookaside Buffer (TLB). The TLB is a cache that stores recent translations of virtual…
ARM Cortex-M85 Dhrystone Benchmark Performance Shortfall with GCC The ARM Cortex-M85 processor is a high-performance microcontroller core designed for embedded applications requiring robust computational capabilities. It is part of the Cortex-M series, which is widely used in real-time systems, IoT devices, and other embedded applications. One of the key metrics used to evaluate the performance…