Staff Memory Systems Design Engineer

Detailed Responsibilities (End-to-End PCIe for NVMe SSD)

1. PHY/MAC IP Review (System Design Perspective)

• Understand criteria for PHY/MAC/controller IP:
  • Gen5/Gen6 readiness, equalization capability, margining hooks, lane mapping flexibility
  • SRNS/SRIS tolerance, clocking modes, power management support
  • Observability: LTSSM state visibility, error counters, replay/NAK stats, equalization telemetry
• Review IP documents:
  • Reset sequences, compliance features, link speed change support
  • L1SS behavior, CLKREQ#/REFCLK control expectations
  • AER robustness, surprise down handling, hot/warm reset behavior
• Specify platform-facing requirements:
  • Retimer/redriver compatibility assumptions (backplane/adaptor/cables)

1. ASIC/SoC Integration Ownership

• Integrate PCIe subsystem with:
  • Clocking: REFCLK handling, clock request gating, clock-down sequences
  • Resets: PERST# behavior, internal resets, warm/hot resets, FLR support as applicable
  • Power domains: retention strategies, wake sources, D-state coordination
  • Sidebands: WAKE#, CLKREQ#, presence detect patterns (platform dependent)
• Define lane policy:
  • x4 typical NVMe, lane reversal/polarity, width detection & recovery from degraded width

1. PCIe SFR / Register + FW Design Guidelines

• Define a clean SFR map that FW uses for:
  • LTSSM control/observability (state, substate, timers, retries)
  • Link speed/width control and status (negotiated vs target)
  • Low-power triggers: ASPM enable/disable, L1SS policy, L0p policy (if implemented)
  • Clock request & clock gating behavior (safe entry/exit rules)
  • Error logging counters (replay, NAK, ECRC, timeout, malformed TLPs)
  • Recovery controls: link disable/enable, retrain, directed speed change, error clear policy
• Provide FW runbooks:
  • What to do when : training fails, width reduces, speed fallback, AER floods
  • Safe sequencing across power modes and APST transitions

1. Link Bring-Up & Transitions (Sequence Ownership)

You ll own/define the exact sequencing rules for:

• Enumeration readiness
  • Ensure config space stability, BAR mapping correctness, MSI/MSI-X readiness timing
• Speed negotiation / Directed Speed Change
  • When to allow Gen5/Gen4 fallback; policy for stability vs performance
• Width detection & recovery
  • Handling degraded width events (x4 x2) and reporting/telemetry
• Link power management
  • ASPM policy and its constraints with NVMe latency targets
  • L1 entry/exit triggers and guard timers
  • L1 Substates (L1.1/L1.2) enablement conditions, wake sources, and clock requirements
  • DLRM handling (as applicable to platform/system) with safe NVMe readiness on resume
  • L0p (if supported) and interaction with performance bursts
• Clock down / clock request
  • Define clock request gating conditions, and safe no transactions in flight criteria
• NVMe APST alignment
  • Coordinate NVMe power states (APST) with PCIe L-states so you don t create:
    • long resume latencies (client)
    • link instability under load (enterprise)

1. Platform Interoperability

• Own differences across laptop and server:
  • Client: aggressive power policies, fast resume, frequent idle entry/exit, D3hot/cold patterns
  • Enterprise: stable performance, high queue depth, error containment, hot-plug-ish behaviors on some platforms
• Validate across:
  • Multiple root complexes, BIOS implementations, OS stacks

Disclaimer: This job description has been sourced from a public domain and may have been modified by Naukri.com to improve clarity for our users. We encourage job seekers to verify all details directly with the employer via their official channels before applying.