As a prerequisite, you should know multivariable calculus, differential equations, and linear algebra. You should also be comfortable working with complex numbers. After that, there's not much math that's specific to introductory quantum mechanics. You'll need to learn about Hilbert space and Dirac notation, but mostly how to apply linear algebra concepts to the physics.
Griffiths' "Introduction to Quantum Mechanics" devotes a whole chapter to the mathematical formalism as well as an appendix to linear algebra concepts that you'll need. Zettili's "Quantum Mechanics: Concepts and Applications" is also good in this respect and, further, it contains many worked examples. I've found McMahon's "Quantum Mechanics Demystified" to be quite accessible as well, though it has quite a few typos.