AXI Configuration and Status Registers
The PCIe Controller uses the concept of regions to send different types of
outbound TLPs (memory, message, etc.). This arrangement allows the static
information in the TLPs to be pre-programmed in the AXI configuration region
registers. The PCIe Controller uses decoding logic to compare
the incoming AXI address to the preprogrammed AXI address in the AXI
configuration registers to determine which region it belongs to. You can
program the region registers using the APB interface. When the PCIe Controller access a region using the corresponding
MASTER_AXI_AW or MASTER_AXI_RADDR
region, the address is selected and is used to supply the static
pre-programmed TLP information.
Each region has a set of descriptor registers to form the TLP: AXI to PCIe address translation (PCIe address registers) and AXI region decoding (AXI address registers). AXI configuration registers also include link down indication bit. Refer to the Titanium PCIe® Controller Registers User Guide for details.
The AXI configuration register set also includes inbound address translation registers. For endpoints, the function number and the bar number is used to find the correct address translation register.