Dual-Port SSD Link Reset Control for Unintended PCIe Link Downs
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing PCIe devices face issues in handling unintended link downs, which can lead to blue screen errors and inefficiencies in data communication, particularly when multiple ports are involved.
Innovation Solution
The PCIe device incorporates a transaction layer, data link layer, and physical layer to generate and manage transaction packets, link packets, and physical packets, with a link training module to negotiate links and maintain data integrity, and a port mode controller to switch between single and dual port modes, enabling independent operation of ports.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a PCIe device supports multi-port operation, then data communication capability is improved, but handling unintended link downs becomes complex and error-prone
Solution Approach 1:
The PCIe device segments the multi-port system into independent port modules, each with its own link training module. This segmentation allows each port to handle link downs independently through dedicated state machines, preventing cross-port interference and improving reliability of link down handling while maintaining multi-port versatility.
Solution Approach 2:
A port mode controller is introduced as an intermediary component that coordinates between multiple ports and the host. This mediator manages port mode transitions (single-port/dual-port modes) and ensures proper link training sequence, enabling complex multi-port operations while maintaining system reliability through centralized control.
2Adaptability or versatility
If port mode switching is implemented, then operational flexibility is improved, but link training complexity increases
Solution Approach 1:
The system implements dynamic port mode switching between single-port and dual-port modes based on host requirements. The port mode controller dynamically adjusts the operational state of each port and initiates appropriate link training sequences, providing operational flexibility while managing complexity through automated mode transitions.
Solution Approach 2:
Before switching between port modes, the system performs preliminary actions including resetting link states and preparing link training modules. This preliminary preparation ensures that link training is initiated in the correct state, reducing complexity by preventing erroneous training sequences and ensuring smooth mode transitions.
3Productivity
If independent port operation is enabled, then data communication efficiency is improved, but port coordination becomes complex
Solution Approach 1:
Each port is segmented into an independent operational unit with dedicated link training and data processing capabilities. This segmentation enables simultaneous independent operation of multiple ports, improving data communication efficiency while the port mode controller manages coordination through standardized interfaces.
Solution Approach 2:
The port mode controller provides universal coordination functionality that works across different port configurations (single-port or dual-port modes). This multi-functional controller handles various coordination scenarios through unified control logic, enabling independent port operation while managing coordination complexity through a standardized universal control mechanism.
Data Source
AI summary
An SSD device comprises a first port linking up with a first host using a first link, a second port linking up with the first host or a second host using a second link, and a port mode controller controlling the first port and the second port to change an operating mode from a dual port mode, in which the first port and the second port operate independently of each other, to a single port mode, in which only the first port operates. The port mode controller controls the second port to reset the second link in a state where the first link is linked up.