On-Chip Communication Architectures

210 CHAPTER 6 Synthesis of On-Chip Communication Architectures

The minimum bus clock speed thus found is used to create (or update) the

local bus speed constraint set 

L(speed)

for the bus B. As an example, if it was pre-

viously allowed to have bus speeds of any multiple of 33 MHz up to a maximum

of 330 MHz, and 

B

is found to be 90 MHz, the new constraint set would be any

multiple of 33 MHz between 99 and 330 MHz.

In the next phase ( Phase 2 in Fig. 6.17 ), a global optimization ( global_opti-

mize) is performed on the matrix by using information gathered from the TLM

simulation in Phase 1. In this phase, fi rst all the buses that ...