How long to wait for an engine to quiesce gracefully before reset (ms)

configname: CONFIG_DRM_I915_STOP_TIMEOUT

Linux Kernel Configuration
└─>Device Drivers
└─>Graphics support
└─>drm/i915 Profile Guided Optimisation
└─>How long to wait for an engine to quiesce gracefully before reset (ms)
In linux kernel since version 5.1 (release Date: 2019-05-05)  
By stopping submission and sleeping for a short time before resetting
the GPU, we allow the innocent contexts also on the system to quiesce.
It is then less likely for a hanging context to cause collateral
damage as the system is reset in order to recover. The corollary is
that the reset itself may take longer and so be more disruptive to
interactive or low latency workloads.

This is adjustable via
/sys/class/drm/card?/engine/*/stop_timeout_ms