SPRUJ28E November 2021 – September 2024 AM68 , AM68A , TDA4AL-Q1 , TDA4VE-Q1 , TDA4VL-Q1
As described in Section 8.1.2.3 MSMC implements inclusive snoop filters for both memory-mapped SRAM and external memory shared space to limit the amount of required snoop traffic. Both the SRAM and external snoop filters encode the following states for each coherent memory block in their respective filtering structures:
As a safeguard MSMC provides a "Broadcast Mode" configuration that forces MSMC to treat all snoop filter entries as BROADCAST_UNIQUE. This results in snoops generated to all applicable coherent masters for snoop filter hits. This mode can be toggled on and off, but the user should be aware that the snoop filter becomes no longer strictly inclusive once enabled since snoop filter entries accessed during this mode are no longer accurately tracking line ownership. Coherency is still maintained in this mode, though additional potentially unnecessary snoop activity may occur. To enable the broadcast mode feature the MSMC_COHCTRL[0] BCM bit should be set to 0x1.