Industry Expert Blogs
A Brief on Message Bus Interface in PIPE-October 24, 2024 |
PHY Interface for the PCI Express (PCIe), SATA, USB, DisplayPort, and USB4 Architectures (PIPE) enables the development of the Physical Layer (PHY) and Media Access Layer (MAC) design separately, providing a standard communication interface between these two components in the system.
In recent years, the PIPE interface specification has incorporated many enhancements to support new features and advancements happening in the supported protocols. As the supported features increase, so does the count of signals on PIPE interface. To address the issue of increasing signal count, the message bus interface was introduced in PIPE 4.4 and utilized for PCIe lane margining at the receiver and elastic buffer depth control.
In PIPE 5.0, all the legacy PIPE signals without critical timing requirements were mapped into message bus registers so that their associated functionality could be accessed via the message bus interface instead of implementing dedicated signals. It was decided that any new feature added in the new version of PIPE specification will be available only via message bus accesses unless they have critical timing requirements that need dedicated signals.