DRV8870: Questions about demo codes Delay_us

Hi,

My customer is evaluating with DRV8860 EVM and they have some related problem. As showed in following figure is the interrupt function in the demo code, it seems to delay 4 period.

Does this period means the clocking period? with a 16Mhz MSP430F2350 as MCU in EVM the total delay time is 1/16Mhz*4=0.25us?

For DRV8860 are there max delay time or any recommended delay time for this ?

Thanks!

Manu