The NoC carries data poisoning information in AXI-MM mode.
The AXI master can set the WPOISON bit and send it to the AXI slave. An AXI slave receives the WPOISON bit, and it can act accordingly. For example, the DDRMC, upon receiving the WPOISON bit, corrupts the ECC syndrome being written to memory. NoC components can set the WPOISON bit at the following:
- NMU AXI master input (write request).
- NMU (on detection of a write data parity error).
The NSU and NPP carry the poison bit from the NMU to the NSU. The WPOISON bit accumulates among multiple flits for upsizing, and splits into multiple flits for downsizing.
The AXI slave can set the RPOISON bit and send it to the AXI master. The AXI master receives the RPOISON bit and it can act accordingly. NoC components can set the RPOISON bit at the following:
- NSU AXI slave input (read response).
- NSU (on detection of a read data parity error).
The NMU and NPP carry the poison bit from the NSU to the NMU. The RPOISON bit accumulates among multiple flits for upsizing, and splits into multiple flits for downsizing.
To enable this feature, set the SI_SIDEBAND_PINS parameter to 'true' in the NoC Properties tab. Use the following Tcl command:
set_property CONFIG.SI_SIDEBAND_PINS 1 [get_bd_cells /axi_noc_0]