Addressing Structure - 2023.2 English

Vivado Design Suite User Guide: Designing IP Subsystems Using IP Integrator (UG994)

Document ID
UG994
Release Date
2023-10-18
Version
2023.2 English

In IP integrator, a connection is made on the block diagram between a Master Interface and a Slave Interface, possibly through interconnect IP. This is called an Address Path. The slave interface will have one or more Slave Segments which are addressable regions of memory or registers that the master wants to access.

Each master block has one or more Address Spaces (for example, an instruction and data address space). The slave segments are visible to the master at specific addresses in a master’s address space. Address Assignment is the act of choosing an base address (that is, the starting address) and range within a master's address space where the slave will be visible to the master. This assigned address is then stored with the master's address space as a Master Segment. A master segment is simply an address assignment, which assigns the base address and range at which a master can access a slave.

The preceding figure illustrations the address path from a Master Interface (master_block) across an Address Path to a Slave Interface (slave_block), allowing a master's Address Space to access a Slave Segment resource. A Master Segment is created within the master's Address Space during address assignment. A Master Segment devotes a portion of the master's Address Space (defined by base address and range) for accessing the Slave Segment resource.

Important: An AXI4-Lite can have a range less than 4K, so a range such as 128 is acceptable. However, these restrictions are in context to AXI4-Lite slaves connected through AXI Interconnect IP. If AXI4-Lite is connected to interconnect with a range less than 4K (for example 128) then it is mandatory that all the slaves connected to that AXI interconnect should either all be AXI4-Lite slaves, or one has to increase the range for this particular AXI4-Lite slave to >= 4K for the design to work.
Figure 1. Address Structure