For consistency across platforms, Golang for Power now fetches the current time in nanoseconds, via the clock_gettime() syscall. Committed as 0df5ab7. This patch fixes issue #11222 for ppc64x.
There is still room for improvement here. Since the minimum kernel requirement is 2.6.37, we can use the VDSO for calling clock_gettime() instead of using the syscall.
Unfortunately, there is no runtime implementation for supporting the VDSO on Power at the moment. I am currently working on that.