How to handle below scenario ?
Consider interconnect has snoop filter. As per the snoop filter the snoop request should be hit in cache but it will be a miss in this case.
This is described in Section D5.2.3 of the ACE Specification. The master that's being snooped can either:
• Give a snoop response with PassDirty deasserted and IsShared asserted, which does not pass permission to store to the line and does not pass responsibility for updating memory.
• Delay the snoop response until the snooped master has completed the update to main memory.
For an eviction (i.e. a WriteBack), it's more likely to perform the second point. In this case, it will return a missed snoop response only after the eviction has completed. The interconnect can then fetch this data from main memory.
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