Provide support for SmartSwitch DPU module graceful shutdown.

Description:

• Single source of truth for transitions

  • All components now use sonic_platform_base.module_base.ModuleBase helpers:

    • set_module_state_transition(db, name, transition_type)
    • clear_module_state_transition(db, name)
    • get_module_state_transition(db, name) -> dict
    • is_module_state_transition_timed_out(db, name, timeout_secs) -> bool

  • Eliminates duplicated logic and race-prone direct Redis writes.

• Correct table everywhere

  • Standardized on CHASSIS_MODULE_TABLE (replaces CHASSIS_MODULE_INFO_TABLE).
  • HLD mismatch addressed in code (HLD fix tracked separately).

• Ownership & lifecycle

  • The initiator of an operation (startup/shutdown/reboot) sets:

    • state_transition_in_progress=True
    • transition_type=<op>
    • transition_start_time=<utc-iso8601>

  • The platform (set_admin_state()) is responsible for clearing:

    • state_transition_in_progress=False
    • optionally transition_end_time=<epoch> (or similar end stamp).

  • CLI pre-clears only when a prior transition is timed out.

• Timeouts & policy

  • Platform JSON path only: /usr/share/sonic/device/{plat}/platform.json; else constants.

  • Typical production values used:

    • startup: 180s, shutdown: 180s (≈ graceful_wait 60s + power 120s), reboot: 120s.

  • Graceful wait (e.g., waiting for “Graceful shutdown complete”) is a platform policy and implemented inside platform set_admin_state()—not in ModuleBase.

• Boot behavior

  • chassisd on start:

    1. Clears stale flags once (centralized sweep).
    2. Runs set_initial_dpu_admin_state() which marks transitions via ModuleBase before calling platform set_admin_state().
    3. Leaves clearing to the platform or to well-defined status transitions (ONLINE/OFFLINE) where appropriate.

• gNOI shutdown daemon

  • Listens on CHASSIS_MODULE_TABLE and triggers only when:

    • state_transition_in_progress=True and transition_type=shutdown.

  • Never clears the flag (ownership stays with the platform).

  • Bounded RPC timeouts and robust Redis access (swsssdk/swsscommon).

• CLI (config chassis modules …)

  • Uses ModuleBase APIs for all set/get/timeout checks.
  • If a previous transition is stuck, is_module_state_transition_timed_out() → auto-clear then proceed.
  • Sets transition at the start of startup/shutdown; platform clears on completion.
  • Fabric card flow retained; edits are surgical.

• Redis robustness

  • Helpers handle both stacks (swsssdk/swsscommon); no hset(mapping=...) usage.
  • Consistent HGETALL/HSET paths; resilient to connector differences.

• Race reduction & consistency

  • Centralized writes prevent multi-writer races.
  • All transition writes include transition_start_time; clears may add an end stamp.
  • Existing PCI/file-lock logic left intact; unrelated behavior unchanged.

• Change scope

  • Minimal, targeted diffs.
  • No background tasks added, no broad refactors beyond transition handling.
  • Behavior changes are limited to making transition semantics correct and uniform across repos.

HLD: # 1991 sonic-net/SONiC#1991
sonic-platform-common: #567 sonic-net/sonic-platform-common#567
sonic-host-services: sonic-net/sonic-host-services#255
sonic-platform-daemons: sonic-net/sonic-platform-daemons#667

How to verify it
Issue the "config chassis modules shutdown DPUx" command
Verify the DPU module is gracefully shut by checking the logs in /var/log/syslog on both NPU and DPU