When the TLP Bypass feature is enabled, the R-tile Avalon® -ST IP does not process received TLPs internally but outputs them to the user application. This allows the application to implement a custom Transaction Layer.
Note that in TLP Bypass mode, the PCIe Hard IP does not generate/check the ECRC. However, you can enable the IP to remove it if the received TLP has the ECRC. The steps on how to do this are described in section ECRC.
The R-tile Avalon® -ST IP in TLP Bypass mode still includes some of the PCIe configuration space registers related to link operation.
In TLP bypass mode, R-tile supports the autonomous Hard IP feature. It responds to configuration accesses before the FPGA fabric enters user mode with Completions with a CRS code.