source of kundalini is Paramasiva, Alakh Niranjan, Mahasivam or Parabrahman in saiva schools (virashaivism, Kashmir Shaivism, natha, saiva siddhanta)

Alakh Niranjan possesses nija shakti (kundalini, god's speech....)
In virashaivism united Sthala (Paramasiva) divided into two: Linga (Siva) and Anga (Jiva), the same thing happens with one shakti, she is divided into two: Kalashakti and Bhaktishakti.
Kalashakti - power of evolution. Bhaktishakti. - involution (laya)... Kalashakti corresponds to Linga (Siva), Bhaktishakti to Anga (jiva).Next Kalashakti divided to 6: cit-shakti, para shakti, adi shakti, iccha shakti, jnana shakti, kriya shakti...In Kasmir 5 powers, in saiva siddhanta 3 (iccha shakti, jnana shakti, kriya shakti).
Bhaktishakti also divided to 6 powers of involution and they corresponds to 6 Anga Sthalas...And 6 powers of Kalashakti corresponds to 6 Linga Sthalas.



For world creation (36 tattvas) mayamala is used...It is acit, asat in saiva siddhanta and virashaivism... But Kashmir Shaivism thinks a little differently....

therefore chakras are forms (rupas) of mayamala and acit, but inside them flows sakti (cit)... Parabindu and bindu in every chakra created from eternal mayamala, which has its source in root mala...(primordial evil)
In saiva siddhanta all bodies, including pure tattvas created from mala....
therefore bodies - source of evil.... they are illuminated only by the powers of God...so kundalini must dissolve the original evil (body, tattva, mala)
However, Kashmir Shaivism and other saiva schools have different approaches to deal with anavamala...Kashmir Shaivism considers all bodies to be transcendental and cit....

Anavamala concept can be found only in saiva schools... vamachara and shakti schools don't talk about it......(other schools talk about avidya)....sankhya "considers" shakti as the energy of unconscious prakriti....
Purusha is powerless, he only behold.... seedless...prakriti and shakti in sankhya are acit....
advaita vedanta also does not consider kundalini-shakti, as Brahman Nirguna....


So shakti is seen as god himself mostly in saiva and shakti schools....
and attention to Laya Yoga (kundalini) is enormous here...