NEX-5R Phase Focus

My manual says "When the aperture value is greater than F6.3, Phase Detection AF is unavailable."  (P 131 GB)

Does anyone know what this means?  I can read it two ways:

1.  If the lens maximum aperture is smaller than f6.3 (eg f8) phase focus won't work.

or

2. If I set my lens to a smaller aperture than f6.3 (so for example I set my f5.6 lens to f8) phase focus won't work.

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Best regards
Vince C