The resource cost when increasing the depth beyond the default value of 2 is similar to the resource cost of PIPOs. Namely, each increment of 1 will require enough memory for a block, for example N * 32-bit words.
The stream of blocks object can be bound to a specific RAM type, by placing the
BIND_STORAGE pragma where the stream-of-blocks is
declared, for example in the top-level function. The stream of blocks uses 2-port block
RAM (type=RAM_2P) by default.