It's possible to generate IPs in Simulink using HDL Coder/System Generator for use in a Vivado project.
Is it possible to import an IP from Vivado to Simulink for seamless system integration?
For example, some IPs related to specific boards are available for inculsion in Vivado projects.
Not sure if this will work - bring these IPs to Simulink using HDL Wrapper option (in Vivado), and include the wrapper in the Blackbox (in Simulink System Generator Xilinx Toolbox). This is just an idea. Is this how it can be done? Else, the IPs would have to be retained in Vivado, and then included with the HDL generated from Simulink. That's another process of dealing with hierarchy and port mapping there!
Please elaborate!