Data coherency manager with mapping between physical and virtual address spaces

A method for processing physically addressed snoop requests, the snoop requests being addressed in a physical address space and relating to a virtually addressed cache memory having a plurality of virtually addressed coherent cachelines addressable using a virtual address space, the method comprising:

• receiving a physically addressed snoop request relating to a physical address;
• determining, from a mapping from physical addresses to virtual addresses for each coherent cache line held in the cache memory, whether the physical address is mapped to a virtual address;
• and
• processing the snoop request in dependence on that determination.

A non-transitory computer readable storage medium having stored thereon a computer readable description of an integrated circuit that, when processed in an integrated circuit manufacturing system, causes the integrated circuit manufacturing system to manufacture a coherency manager for receiving physically addressed snoop requests, the snoop requests being addressed in a physical address space and relating to a virtually addressed cache memory addressable using a virtual address space, the cache memory having a plurality of virtually addressed coherent cachelines, the coherency manager comprising:

• a reverse translation module configured to maintain a mapping from physical addresses to virtual addresses for each coherent cacheline held in the cache memory;
• and
• a snoop processor configured to:
• receive a physically addressed snoop request relating to a physical address;
• in response to the received snoop request, determine whether the physical address is mapped to a virtual address in the reverse translation module;
• and
• process the snoop request in dependence on that determination.