HRTIMER input frequency

Can the HRTIMER input frequeny be lower than the maximum value given in the datasheets? E.g. on a G74 with HRTIMER input at 125 MHz, steps would be nice 250 ps versus 188.2... ps at 170 MHz.

The functional description "HRTIM timer is made of a digital kernel clocked at 170 MHz followed by delay lines. " is a strong hint that only one frequency fits, but some confirmation is welcome.