One eye open CBS
from Styles P (Ft. Bun B) – Yo Trill Shit Lyrics on Rap Genius
Meaning
Styles P always has one eye open kind of like the CBS logo:

He’s always on the look out for bitch niggas(referred to in the previous line) who will try to bring him down seeing as how he is involved with drugs (BMF and CVS references at the beginning of the verse)
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