cache/prefetch/Prefetcher.py

4 # The license below extends only to copyright in the software and shall
5 # not be construed as granting a license to any other intellectual
6 # property including but not limited to intellectual property relating
7 # to a hardware implementation of the functionality of the software
8 # licensed hereunder.  You may use the software subject to the license
24 # contributors may be used to endorse or promote products derived from
70     sys = Param.System(Parent.any, "System this prefetcher belongs to")
128     cache_snoop = Param.Bool(False, "Snoop cache to eliminate redundant request")
135     # - If set to 100, all candidates can be discarded (one request
136     #   will always be allowed to be generated)
137     # - Setting it to 0 will disable the throttle control, so requests are
139     # - If set to 60, 40% of candidates will generate a request, and the
161     degree = Param.Int(4, "Number of prefetches to generate")
172     degree = Param.Int(2, "Number of prefetches to generate")
200     shift_values = VectorParam.Int([2, 3, 4, -3], "Shift values to evaluate")
203         "Counter threshold to start the indirect prefetching")
205         "Counter threshold to enable the stream prefetcher")
207         "Number of prefetches to generate when using the stream prefetcher")
215         "Number of bits to shift when calculating a new signature");
245         "Minimum confidence to issue prefetches")
247         "Minimum confidence to continue exploring lookahead entries")
281         "Limit the strides checked up to -X/X, if 0, disable the limit")
309         "Memory latency used to compute the required memory bandwidth")
326         "Lower bits to mask when comparing deltas")
355     degree = Param.Unsigned(4, "Number of prefetches to generate")
377         "Indexing policy of the Physical-to-Structural Address Map Cache")
380         "Replacement policy of the Physical-to-Structural Address Map Cache")
385         "Indexing policy of the Structural-to-Physical Address Mao Cache")
388         "Replacement policy of the Structural-to-Physical Address Map Cache")
414     score_max = Param.Unsigned(31, "Max. score to update the best offset")
415     round_max = Param.Unsigned(100, "Max. round to update the best offset")
418     tag_bits = Param.Unsigned(12, "Bits used to store the tag")
429                 "Cycles to delay a write in the left RR table from the delay \
439     score_threshold_pct = Param.Percent(25, "Min. threshold to issue a \
440         prefetch. The value is the percentage of sandbox entries to use")