the 1099-R should already specify that with distribution code G or some equivalent code (the back of the 1099-R explains the codes), taxable amount 0 and "total distribution" checked in 2b instead of "taxable amount not determined" - if that's the case when you input it there will be some questions about whether it was rolled over to Roth etc. check that the tax is not impacted and you should see on your 1040 line 5a has the amount of the rollover, 5b will say ROLLOVER and $0 tax.
