mini2440 pwm request_irq

i make one module and in that i am generating 2MHz clock on pwm pin 
        s3c2410_gpio_cfgpin(S3C2410_GPB(0), S3C2410_GPB0_TOUT0);

So i am success fully generating 2MHZ clock.
but now i am capture rising edge using below API of pwm on TimerHandler
Function so it is also work but My Gui is hand due to 2MHZ so not able to
do any activity from user application.

request_irq(IRQ_TIMER0, TimerINTHandler0, IRQF_TRIGGER_RISING,
DEVICE_NAME,&TimDev0);



So is there any another way to detect rising edge of pwm timer