typedef enum logic [1:0] {
    GETLINE        = 2'b01,  // Request data for modified line in L1
    SENDLINE       = 2'b10,  // Send requested cache line to L1
    INVALIDATELINE = 2'b11,  // Invalidate a line in L1
    EVICTLINE      = 2'b00   // Evict a line from L1
} l2_l1_message_e;