Is there a permanent cure for premature ejaculation?

Many options. Distract by thinking nonsexual thoughts. "stop and start":  stop stimulation before ejaculation for 30 seconds and restart. Repeat as desired.  "squeeze" method: man or partner gently squeezes the end of penis (where the glans meets the shaft) for several seconds. Stop stimulation for 30 seconds, and restart . repeat as desired. Ssris such as prozac (fluoxetine). use condom/local anesthetic cream.
Nothing is permanent. There are urologic mechanisms; sexual dysfunction techniques; and medication. Many of the antidepressants will actually treat premature ejaculation. Also the squeeze technique manually can be effective.
Yes. Yes but this is a complex problem. Talk to your urologist.
Reprogram yourself. Get really good using the squeeze technique with your partner and normal timing will often become second nature.