Nios® V Processor: Lockstep Implementation

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ID 833274
Date 10/07/2024
Public
Document Table of Contents
Document Table of Contents x
1. About the Nios® V Processor Lockstep 2. Overview 3. Controlling the Nios® V Processor Lockstep 4. Programming Model 5. Signals, Interfaces, and Build Parameters 6. Using Nios® V Processor Lock Step A. Document Revision History for the Nios® V Processor: Lockstep Implementation B. Appendix
1. About the Nios® V Processor Lockstep x
1.1. Nios® V Processor Lockstep Features
2. Overview x
2.1. Introduction 2.2. Main Principles 2.3. Operating Modes 2.4. Resets 2.5. LOGS Information
2.2. Main Principles x
2.2.1. System Phases 2.2.2. System States 2.2.3. Safety Mechanisms
2.2.2. System States x
2.2.2.1. Transitioning between System States
2.2.3. Safety Mechanisms x
2.2.3.1. Self-Checking Comparator 2.2.3.2. Timeout Timer 2.2.3.3. Enable Counters 2.2.3.4. Specialized Safety Mechanism
2.3. Operating Modes x
2.3.1. NORMAL and SILENT Modes
2.4. Resets x
2.4.1. Resetting CORE 2.4.2. Resetting OPTIONS 2.4.3. Resetting LOGS 2.4.4. Resetting Time Diversity Register
2.5. LOGS Information x
2.5.1. ALARMS 2.5.2. CONTEXT 2.5.3. STATISTICS 2.5.4. Reset LOGS
2.5.1. ALARMS x
2.5.1.1. Configuring Alarm Severity
3. Controlling the Nios® V Processor Lockstep x
3.1. Configuration Interface 3.2. fRNET Interface 3.3. Controlling the Elective Features
3.3. Controlling the Elective Features x
3.3.1. Applying Timeout and Comparator Blind Window 3.3.2. Injecting Fault 3.3.3. Downloading the CPU Software 3.3.4. Debugging the CPU Software using SILENT Mode 3.3.5. Resetting the CPU upon Fault Detection
3.3.1. Applying Timeout and Comparator Blind Window x
3.3.1.1. Timeout 3.3.1.2. Comparator Blind Window 3.3.1.3. Calculating the Blind Window and Timeout Period
3.3.2. Injecting Fault x
3.3.2.1. Root Fault Injection 3.3.2.2. Alarm Fault Injection
3.3.4. Debugging the CPU Software using SILENT Mode x
3.3.4.1. Entering SILENT Mode 3.3.4.2. SILENT Mode Limitation 3.3.4.3. Exiting SILENT Mode
3.3.5. Resetting the CPU upon Fault Detection x
3.3.5.1. Basic Reset Control
4. Programming Model x
4.1. Memory Map 4.2. Configuring fRSmartComp during Run-time 4.3. Unlocking and Locking Registers 4.4. Detailed Register Description
4.1. Memory Map x
4.1.1. Memory Map—Part 1 4.1.2. Memory Map—Part 2 4.1.3. Memory Map—Part 3
4.4. Detailed Register Description x
4.4.1. DCLSM Blind Window Control Register - DCLSM_BWCR 4.4.2. All Alarms’ Prior Alarms’ Fault Injection Register - ERRCTRL_ALL_ALARMS_PRIOR_AFI 4.4.3. INTREQ Configuration Register - ERRCTRL_INTREQ_CONF 4.4.4. Timeout Deadline and Status Register - ERRCTRL_TIMEOUT 4.4.5. Timeout Acknowledgment Register - ERRCTRL_TIMEOUT_ACK 4.4.6. Enable Key fRSmartComp Control Register - ERRCTRL_ENABLE_KEY 4.4.7. Root Fault Injection Control register - ERRCTRL_ROOT_INJ 4.4.8. Alarm Fault Injection Control register - ERRCTRL_ALARM_INJ 4.4.9. Event Mask Configuration register - ERRCTRL_MASKA and ERRCTRL_MASKB 4.4.10. Alarm Routing Configuration register - ERRCTRL_ROUTA and ERRCTRL_ROUTB 4.4.11. Error Controller PGO LOG Reset Control register - ERRCTRL_PGOLOGRST 4.4.12. PGO0 and PGO4 Configuration registers - ERRCTRL_PGO0 and ERRCTRL_PGO4 4.4.13. FN_MODEIN Control Register - ERRCTRL_FNMODEIN 4.4.14. FN_MODEOUT register - ERRCTRL_FNMODEOUT 4.4.15. All Alarms After Fault Injection - ERRCTRL_FNGIALARMS 4.4.16. Error Controller Context Register - ERRCTRL_FNGICTXT4 4.4.17. CMP Mismatch CONTEXT Registers - ERRCTRL_FNGICMPCTXT0 … ERRCTRL_FNGICMPCTXT3 4.4.18. STATISTICS registers: ERRCTRL_FNGISTAT0 and ERRCTRL_FNGISTAT4 4.4.19. State register - ERRCTRL_FNPERIPHGI4
5. Signals, Interfaces, and Build Parameters x
5.1. Configuration Interface 5.2. System Interface 5.3. fRNET Interface 5.4. IP Parameters
5.3. fRNET Interface x
5.3.1. CONFIG 5.3.2. INFO
6. Using Nios® V Processor Lock Step x
6.1. Instantiating Lockstep-Enabled Processor 6.2. Connecting Signals and Interfaces 6.3. Compiling Design 6.4. Implementing Startup Procedure 6.5. Applying Optional Injection for Validation 6.6. Detecting Faults 6.7. Handling Faults (Safety Use Case)
6.2. Connecting Signals and Interfaces x
6.2.1. Connecting Clock and Reset 6.2.2. Connecting Configuration Interface 6.2.3. Connecting System Interface
6.2.1. Connecting Clock and Reset x
6.2.1.1. Clock 6.2.1.2. Reset
6.2.3. Connecting System Interface x
6.2.3.1. Asynchronous Reset Interface 6.2.3.2. CPU Halt and Restart Acknowledgment Interface 6.2.3.3. Silent Mode Interface 6.2.3.4. Output Qualification (TERMS_LEFT and TERMS_RIGHT) 6.2.3.5. Interrupt Request (INTREQ) 6.2.3.6. ALARMS Interfaces 6.2.3.7. Connecting fRNET Interface
6.7. Handling Faults (Safety Use Case) x
6.7.1. UC_01: Standard Fail Safe or No Availability 6.7.2. UC_02: False Positive Avoidance 6.7.3. UC_03: Timeout on System Reset or After Fault Detection
1. About the Nios® V Processor Lockstep
2. Overview
3. Controlling the Nios® V Processor Lockstep
4. Programming Model
5. Signals, Interfaces, and Build Parameters
6. Using Nios® V Processor Lock Step
A. Document Revision History for the Nios® V Processor: Lockstep Implementation
B. Appendix

2.2.3.2. Timeout Timer

You can use timeout timers to detect any faulty behavior of the external units that incorrectly interact with the fRSmartComp (for example, the System Supervisor has not accessed the fRSmartComp for a long period of time).

After asynchronous reset and during any fRSmartComp state change, a single timer counter starts with the configured deadline value in the IP Parameter Editor. You can configure these values during application runtime. If the timer expires without receiving a timeout acknowledgment, it generates a timeout alarm (ALARM16).

To set the timeout deadline value, you use the approach in the following table.

Table 6.  Setting the Timeout Deadline
Approach Actions
IP Parameter Editor (during project development) Defines the default timeout deadline in the Default Timeout Period option.
Configuration Interface (during runtime)
  1. Write ERRCTRL_TIMEOUT[31:25] with value=0x19 to unlock the register.
  2. Verify the register is unlocked through ERRCTRL_TIMEOUT[24].
  3. Write ERRCTRL_TIMEOUT[7:0] with a desired value to change the timeout deadline.
  4. Write ERRCTRL_TIMEOUT[31:25] with value=0x00 to lock the register.

To acknowledge the timeout, use the approach in the following table.

Table 7.  Acknowledging the Timeout
Approach Actions
Configuration Interface (during runtime)
  1. Write ERRCTRL_TIMEOUT_ACK[31:0] with value = 0x78A5C3E1.
  2. Write ERRCTRL_TIMEOUT_ACK[31:0] with value = 0x875A3C1E.
Figure 10. Timeout Timer
Level Two Title