TT is itemizing deduct,ns, but not factoring in mortgage int deduct. My combined property, sales & vehicle tax is capped at combo of $10K. Does this $10K = no mort ded?

I can't find info that clearly states that the mortgage interest piece is part of the $10K salt cap.  The explanations seem to say it doesn't come into play if you use the standard deduction - but I'm itemizing?  Need help understanding this element.