Associative cache and method for replacing data entries having an IO state

A method of replacing a data entry in a way of an associative cache with new data, the method comprising the following steps:

• selecting a set of ways within the cache, each way storing a data entry;
• checking if a data entry in a way of the set is invalid;
• if so, replacing the invalid data entry in the way with the new data;
• if not, checking if a state tag corresponding to a data entry in a way of the set has an input-output (IO) state;
• if a state tag corresponding to a data entry in a way of the set has an IO state, replacing the data entry with the new data and marking the state tag to reflect whether the new data was brought into the cache by request of an IO agent;
• if no state tag corresponding to a data entry in a way of the set has an IO state, selecting a data entry in a way of the set according to a different cache replacement algorithm;
• and
• replacing the selected data entry in the way with the new data.

A method of replacing a data entry in a way of an associative cache with new data, the method comprising:

• selecting a set of ways within the cache, each way storing a data entry;
• checking if a data entry in a way of the set has an input-output (IO) state;
• and
• if so, replacing the data entry with the new data.