To paraphrase an Austen line, it is a truth universally acknowledged that implementation, power intent and design hierarchy don’t always align very well. Hierarchy is an artifact of legacy structure, reuse and division of labor, perhaps well-structured piecewise for other designs but not necessarily so for the design you now face, which has a different power objectives and different physical constraints. Power and implementation want to be at least partly flat which doesn’t blend well with a rigid hierarchy.
REGISTER NOW for this webinar on Tuesday, Jun 13, 2017 10:00 AM – 11:00 AM PDT
You can see this in several examples. It often makes sense to merge common power islands to optimize power switching and PG routing, but the RTL hierarchy gets in the way. You could manually restructure the hierarchy, but that can be a lot of work, not just in making the changes but also in verifying you didn’t break anything. As another example, a classic trick in P&R is to run feedthrus through a block to optimize timing for long runs. This could be handled nicely purely within physical design before complex power strategies became common. Now if the blocks involved sit in different power domains, these changes must also be reflected in netlists for power verification. Or think about a timing critical I/O interface in a legacy design, now repurposed to a derivative. That interface perhaps sat deep in a hierarchy in the original design but must be moved to a different hierarchy to better suit floorplanning objectives in the derivative. But all connections to the rest of the logic must be preserved.
In this webinar, DeFacto will present their solution for RTL design restructuring, within their STAR platform, to automate this complex task. This appears so easy you might well consider restructuring as a new aid to further optimize power management and area in your design.