PCI is an memory-mapped, dynamically reconfigurable interconnect protocol, so that the same physical register may be accessed in several different ways. The current chapter targets to describe only the statically-mapped programming registers of the local PCIe controller, accessed over the local AXI slave.
They are composed of:
- PCIe-standard configuration registers: by definition accessible over the PCIe wire through the PCIe configuration (and extended configuration - ECAM) space. Those registers are different depending on the selected mode (Type-0: EP or Type1: RC).
- Port Logic (PL) registers: non-standard user-accessible registers for additional PCIe functionality. They are also accessible over PCIe wire, in the configuration (ECAM) space.
- TI-specific control and status registers: more non-standard registers, accessible only locally. These are associated with the PCIe controller wrapper level functional control and status.