DRM database property: IN_FENCE_FD

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Details

Name

IN_FENCE_FD

Flags

atomic

Type

signed range

Attached to

plane

Specification

[-1, INT32_MAX]

Documentation

Use this property to pass a fence that DRM should wait on before
proceeding with the Atomic Commit request and show the framebuffer for
the plane on the screen. The fence can be either a normal fence or a
merged one, the sync_file framework will handle both cases and use a
fence_array if a merged fence is received. Passing -1 here means no
fences to wait on.

If the Atomic Commit request has the DRM_MODE_ATOMIC_TEST_ONLY flag
it will only check if the Sync File is a valid one.

On the driver side the fence is stored on the @fence parameter of
&struct drm_plane_state. Drivers which also support implicit fencing
should extract the implicit fence using drm_gem_plane_helper_prepare_fb(),
to make sure there's consistent behaviour between drivers in precedence
of implicit vs. explicit fencing.

Driver support