Do you use CTimer module or SCTimer/PWM module to generate the PWM signal? If you use CTimer to generate the PWM signal, as you know that the PWM Reset match register will be
so it is okay to set the match register as 9000 which reset the counter.
If you use SCTimer/PWM module, you can set the limit register as 9000, which sets up the PWM frequency.
Hope it can help you