SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
Because only incremental burst mode is supported, the PCIe addresses can not be in a cacheable memory space. Subsequently, cache coherence protocol is not involved, and the PCIe controller is not expected to receive coherent PCIe TLPs (NS=0). For safety purpose, the PCIe controller coherent feature must be permanently disabled (and this applies for the device by default) by keeping PCIECTRL_TI_CONF_SYSCONFIG[16] MCOHERENT_EN at value 0b0. In that case, inbound coherent PCIe TLPs ( that means with NS=0) proceed normally, but coherence will not be guaranteed by the device.