Bus Master Error Notification via Mode Information

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current data access systems require separate bus configurations for speculative and non-speculative accesses, leading to increased circuit complexity and size for the bus master, as they cannot differentiate between the two types of accesses.

Innovation Solution

Incorporating mode information in bus requests to determine whether error notification is performed by the bus slave or the bus master, allowing the bus master to perform error notification for speculative accesses and the bus slave for non-speculative accesses, thereby reducing the circuit scale of the bus master.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If separate bus configurations are used for speculative and non-speculative accesses, then error notification reliability is improved, but device complexity increases

Engineering Contradiction:
Improveerror notification reliabilityVSAvoidbus configuration complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments the error notification function by introducing mode information in bus requests to distinguish between speculative and non-speculative accesses. This allows the bus master to selectively control which device (bus master or bus slave) performs error notification based on the access mode, resolving the contradiction by functional segmentation rather than physical bus separation.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent makes the error notification mechanism dynamic by allowing the bus master to change the notification mode based on the type of access (speculative or non-speculative). The bus master can dynamically switch between slave-mode notification and master-mode notification, eliminating the need for separate static bus configurations while maintaining reliability.

Inventive Principle:
Principle #15Dynamics

2Measurement precision

If separate bus configurations are used for speculative and non-speculative accesses, then error notification accuracy is improved, but circuit scale increases

Engineering Contradiction:
Improveerror notification accuracyVSAvoidcircuit scale
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent applies universality by designing a single bus configuration that can handle both speculative and non-speculative accesses through mode information. The bus master circuit is designed to perform multiple functions: it can act as both the initiating master and the error notification master depending on the access mode, eliminating the need for separate dedicated circuits for each access type.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent changes the parameter of bus request mode information to distinguish between speculative and non-speculative accesses. By modifying the request parameters rather than creating separate physical configurations, the system achieves accurate error notification while keeping the circuit scale manageable through parameter-based differentiation.

Inventive Principle:
Principle #35Parameter changes

3Device complexity

If bus master performs error notification for all accesses, then device complexity is reduced, but error notification reliability deteriorates for speculative accesses

Engineering Contradiction:
Improvebus master circuit complexityVSAvoiderror notification reliability
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent makes the error notification mechanism dynamic by allowing the bus master to change the notification mode based on the type of access (speculative or non-speculative). The bus master can dynamically switch between slave-mode notification and master-mode notification, eliminating the need for separate static bus configurations while maintaining reliability.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent introduces feedback through mode information in bus requests, where the bus master receives feedback about the access type (speculative or non-speculative) and adjusts its behavior accordingly. This feedback mechanism allows the bus master to reliably determine when to perform error notification and when to let the bus slave handle it, maintaining reliability without increasing complexity.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP3428799B1Data access device and access error notification method
Publication Date: 2024.02.21 RENESAS ELECTRONICS CORP
  • EP3428799B1 patent drawingFigure 1~2
  • EP3428799B1 patent drawingFigure 3
  • EP3428799B1 patent drawingFigure 4

AI summary

Error notification by a bus master for a speculative access and error notification by a bus slave for a non-speculative access are achieved while a circuit scale of the bus master is suppressed. A bus request includes mode information for selecting that error notification for an access is performed by the bus slave or the bus master. In a case where the mode information indicating that error notification is performed by the bus slave is included in the bus request, when an error for an access in that bus request has occurred, the bus slave performs error notification. In a case where execution of an instruction of a speculative load access has been fixed and error information for the load access has been received from the bus slave, the bus master performs error notification based on the error information.