AndesCore™ D45-SE

AndesCore™ D45-SE Overview

  • 32-bit in-order dual-issue 8-stage pipeline CPU architecture
  • AndeStar™ V5 Instruction Set Architecture (ISA)
    • Compliant to RISC-V RV32 GCBP little endian:
    • RV-GC: Integer, single/double precision floating point and 16-bit extensions
    • RV-B Bit manipulation extensions 
    • RV-P (draft) DSP/SIMD extensions
    • Andes V5 performance/code size extensions
  • 16/32-bit mixable instruction format for compacting code density
  • Advanced low power branch predication to speed up control code
  • Return Address Stack (RAS) to accelerate procedure returns
  • Physical Memory Protection(PMP), and programmable Physical Memory Attribute (PMA)
  • MemBoost for heavy memory transactions
  • Flexibly configurable Platform-Level Interrupt Controller (PLIC) for supporting wide range of system event scenarios
  • Enhancement of vectored interrupt handling for real-time performance
  • Advanced CoDense™ technology to reduce program code size

The 32-bit D45-SE is an 8-stage superscalar processor that supports ISO 26262 ASIL (Automotive Safety Integrity Level) -D level functional safety for automotive applications. Approved based on the functional safety assignments of a Safety Element Out-of-Context (SEooC), which includes the ISO 26262 compliant development process and the qualitative approach with respect to hardware safety analysis, D45-SE is certified to be used in safety-related applications such as Millimeter Wave Radar Sensor, Around View Monitor system (AVMS), Vehicle Instrument Cluster, Powertrain DCU, Infotainment DCU, Front/Rear different applications for ZCU.

The D45-SE includes “G” (“IMAFD”) standard instructions, “C” 16-bit compression instructions, “P” Packed-SIMD/DSP instructions, and  “B” bit manipulation. D45-SE equipped with comprehensive SIMD/DSP instructions that can boost the performance of voice, audio, image and signal processing. Its ”B” extensions provide some combination of code size reduction, performance improvement, and energy reduction, and “FD” extensions support IEEE754-compliance single and double precision floating point instructions. D45-SE incorporates MemBoost to greatly enhance memory bandwidth and reduce memory latencies for applications with intensive memory accesses. Other features include ECC for memory soft error protection, Platform-Level Interrupt Controller (PLIC) with enhancements for vectored dispatch and priority-based preemption, CoDense™ and StackSafe™ for software quality improvement, PowerBrake and WFI for power management.

Applications

  • Supports a wide range of applications from ASIL B to ASIL D, including Millimeter Wave Radar Sensor, Around View Monitor system (AVMS), Vehicle Instrument Cluster, Powertrain DCU, Infotainment DCU, Front/Rear different applications for ZCU.
  • Compliant with ISO 26262:2018 standard parts 2, 4, 5, 7, 8 and 9 for ASIL-D
  • Independent assessment and certification by SGS-TÜV Saar GmbH
  • AndesCore™ D45-SE ISO 26262 compliant certificate (need to add diagram connection)
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Block Diagram

Development Tools

  • AndeSight™ Integrated Development Environment
  • ICE debugging hardware

Key Features and Performance

ISO 26262 Functional Safety

Key FeaturesBenefits
Certified according to ISO 26262:2018 edition series of standardsCompliant with the latest version of standards
Andes Technology Development Process certified by parts 2, 4, 5, 6, 8 and 9 of the standards for components up to ASIL DTo prevent systematic failures
AndesCore™ D45-SE CPU IP certified by parts 2, 4, 5, 7, 8 and 9 of the standards in compliance with ASIL D requirements. Auxiliary document (Application Note) to help licensee to pass ASIL-B.To prevent random hardware failures
Supporting internal and external safety mechanisms; including qualitative DFMEA (Design Failure Mode and Effects Analysis) and quantitative FMEDA (Failure Modes, Effects, and Diagnostic Analysis) evaluationsFacilitate functional safety product integration and certification
Certified by SGS-TÜV Saar GmbH, with DAkkS logoAudited independently by credible third-party certification body




AndeStar™ V5 Architecture

Key FeaturesBenefits
RISC-V RV32GCPB ISA
  • State-of-the art ISA from latest developments in computer architecture
  • Industry standard and open architecture
Andes Extended InstructionsAndes exclusive performance and functionality enhancements
16/32-bit mixable instruction formatFor compact code density
32 general-purpose registersFor better code size and performance
Machine (M), User (U) and Supervisor (S) Privilege levelsFor Linux and advanced operating systems with protection between kernel and user programs

CPU Core

Key FeaturesBenefits
6.12 Coremark/MHz, 2.96 DMIPS/MHz*Excellent performance-per-MHz
8-stage dual-issue in-order pipelineSuperior performance-efficiency, while allowing for high speeds

Extensive branch predication features

  • Branch Target Buffer (BTB)
  • Branch History Table (BHT)
  • Return Address Stack (RAS)
  • Branch Target Buffer and Branch History Table to speed up control codes
  • Return Address Stack to speeds up procedure returns
Physical Memory Protection (PMP), configurable up to 32 regionsBasic read/write/execute memory protection with minimum cost
Programmable Physical Memory Attribute (PMA), configurable up to 16 regions

Configurable memory attributes:

  • Memory, I/O, None
  • Cacheable/Non-cacheable
  • Write-back/Write-through
  • Read/write/read & write allocate, no allocate
  • Access fault for non-existent regions
Performance monitorsProgram code performance tuning

Multiplier options

  • Fast multiplier: pipelined, 2-cycle
  • Small multipliers: producing 1, 2, 4, or 8 bits per cycle
Option to choose between speed and area according to application's requirements
PowerBrake technologyPerformance throttling to digitally reduce power consumption
StackSafe™ hardware stack protection
  • Easy identification of stack size threshold during development
  • Hardware error detection of stack overflow and underflow at runtime
QuickNap™ technologyFast power-down/wake-up support for caches

* BSP v5.1.0, DMIPS/MHZ follow Dhrystone’s no-inline ground rules, best performances

Memory Subsystems

Key FeaturesBenefits

I-Cache & D-Cache

  • Size: 8KB to 64KB
  • Set associativity: Direct, 2-way or 4-way
  • Accelerating accesses to slow memories
  • Flexible cache configurations

ILM & DLM

  • Size: 4KB to 16M
  • SRAM or AXI interface support
  • Bus masters accesses by AXI slave port
  • For deterministic and efficient program execution
  • Flexible size selection to fit diversified needs
MemBoost Optimize cache reads and writes to achieve higher bandwidth and lower latency
Soft-error protection: parity for I-Cache, and ECC for D-Cache, ILM and DLMCode and data integrity protection
Bus master port: AXI with 64/128-bit dataUser-selectable bus interface for optimal efficiency
Bus save port: AXI with 64/128-bit data, for ILM/DLM accessesEfficient data transfer between CPU and SoC masters
Core/bus clock ratio of N:1Simplified SoC integration
64-bit AXI Peripheral Port InterfaceFor latecny-sensitve peripheral

Platform-Level Interrupt Controller (PLIC)

Key FeaturesBenefits

Implements RISC-V PLIC specification

  • Up to 1023 PLIC interrupt sources
  • Up to 255 PLIC interrupt priority levels
  • Up to 16 PLIC interrupt targets
Allow individual interrupts to be serviced and prioritized without sharing

Enhanced interrupt features

  • Vectored interrupt dispatch
  • Priority-based preemption
  • Selectable edge trigger or level trigger
  • Faster interrupt handling for real-time applications
  • Complete hardware preemption support for faster response
  • Flexible interrupt source interface for simpler SoC design

Debug Support

Key FeaturesBenefits
Implements RISC-V debug specifications ver 0.13Supported by industry debug tool suppliers
JTAG Debug PortIndustry-standard support
Embedded Debug Module with up to 8 triggersFlexible configurations to tradeoff between gate count and debugging capabilities
Exception redirection supportEntering debugger upon selected exceptions without using breakpoints

Trace Support

Key FeaturesBenefits
Implements RISC-V Trace 1.0 Instruction Trace interfaceSupported by Andes tools

Product Package

AndesCore™ D45-SE Single-core Processor with AE350 AXI Platform

  • Pre-integrated D45-SE single-core CPU subsystem, PLIC, Debug Module, and AXI Platform
  • D45-SE processor core certified for functional safety usage
  • Safety package for safety developments
  • AE350 platform for design reference