ARM Cortex-R5 Heroncell_DCCM Module fault_s Signal Unknown at Power-Up The fault_s signal in the Heroncell_DCCM module of the ARM Cortex-R5 is holding an unknown value (X) during the power-up sequence. This issue arises during the SOC_FSM_WAIT_POR_STABLE state, where the fault_s signal is asserted with the clock running. The unknown value propagates to the dccmout and…
Cache Line Faults and Their Impact on ARM-Based SoC Performance Cache line faults, often referred to as "bad bits," can significantly degrade the performance and reliability of ARM-based System-on-Chip (SoC) designs. These faults can manifest as calculation errors, process failures, or even system crashes, particularly in scenarios where data integrity is critical. The cache memory,…
HTRANS Busy State and HREADY Signal Interaction During AHB Read Operations The interaction between the HTRANS signal and the HREADY signal in the ARM AHB (Advanced High-performance Bus) protocol is a critical aspect of ensuring correct data transfer between the master and slave devices. The HTRANS signal indicates the type of transfer being initiated by…
AXI QoS Mechanism and Observed In-Order Behavior The AXI (Advanced eXtensible Interface) protocol incorporates Quality of Service (QoS) signaling to manage transaction priorities and optimize system performance. The QoS values, represented by the AxQoS signals (awqos for write transactions and arqos for read transactions), are intended to influence the priority and ordering of transactions within…
ARM Cortex-M3, R5, and A-Series Debug Integration Challenges When designing a heterogeneous ARM-based SoC with multiple cores such as Cortex-M3, Cortex-R5, and Cortex-A series processors, one of the critical decisions revolves around the debug infrastructure. The debug infrastructure is essential for ensuring visibility into the system during development, testing, and post-silicon validation. The primary challenge…
APB Protocol Requirements for PSELx Deassertion After Transaction Completion The Advanced Peripheral Bus (APB) protocol, part of the ARM AMBA family, is designed for low-power, low-complexity peripheral communication. One of its key requirements is that the peripheral select signal, PSELx, must be deasserted (set to 0) at the end of a transaction unless a back-to-back…
Clock Domain Crossing (CDC) Violations in cxdapswjdp Module The cxdapswjdp module is a critical component in the CoreSight debug architecture, responsible for interfacing between the SWCLKTCK and DAPCLK clock domains. Clock Domain Crossing (CDC) violations detected by Spyglass in this module indicate potential synchronization issues between these two asynchronous clock domains. The SWCLKTCK domain typically…
ARM 22nm TSMC 22ULL-GL Memory Power-Up/Down Sequence Violations The ARM 22nm TSMC 22ULL-GL memory, specifically the TS83Cx00x series, requires a strict power supply sequence for VDDCE (Core Power Supply) and VDDPE (Peripheral Power Supply) during power-up and power-down operations. The correct sequence is critical to ensure the memory operates within its specified electrical and timing…
APB4 PSTRB Signal Behavior During Read Transfers The APB4 protocol, as part of the ARM AMBA family, is designed to be a simple, low-power, and low-complexity interface for peripherals. One of its key features is the inclusion of the PSTRB signal, which is a write strobe used to indicate valid byte lanes during write transactions….
ARM NI-700 Interconnect P-Channel Handshake Race Condition During Power Domain Transition The ARM NI-700 interconnect is a highly configurable and scalable network interconnect designed for advanced SoCs. It supports multiple power domains, enabling efficient power management by allowing individual domains to transition between ON and OFF states. However, during power domain transitions, particularly when the…