libhwcomposer: MDP partial frame update
This change adds support in HWC for MDP partial update applicable
only for command mode panels. Presence of MDP FB (GRAM) in
command mode panels allows MDP clients to update only the updating region
of the frame as rest of the frame will be cached in the GRAM.
HWC calculates the updating region of a frame (ROI) by deducing
outer bounds of its updating layer destinations. Layers not lying
within the calculated ROI will be dropped from the composition
since its illegal to program MDP pipes for non participating layers.
Change-Id: I890d98ff7960fe888787981803cac62f68471201
7 files changed