Param: Transition to Cycles for relevant parameters

This patch is a first step to using Cycles as a parameter type. The
main affected modules are the CPUs and the Ruby caches. There are
definitely plenty more places that are affected, but this patch serves
as a starting point to making the transition.

An important part of this patch is to actually enable parameters to be
specified as Param.Cycles which involves some changes to params.py.

src/mem/Bus.py

@@ -49,7 +49,7 @@ class BaseBus(MemObject):
     master = VectorMasterPort("vector port for connecting slaves")
     # Override the default clock
     clock = '1GHz'
-    header_cycles = Param.Int(1, "cycles of overhead per transaction")
+    header_cycles = Param.Cycles(1, "cycles of overhead per transaction")
     width = Param.Int(8, "bus width (bytes)")
     block_size = Param.Int(64, "The default block size if not set by " \
                                "any connected module")

src/mem/cache/BaseCache.py

@@ -37,7 +37,7 @@ class BaseCache(MemObject):
     assoc = Param.Int("associativity")
     block_size = Param.Int("block size in bytes")
     latency = Param.Latency("Latency")
-    hash_delay = Param.Int(1, "time in cycles of hash access")
+    hash_delay = Param.Cycles(1, "time in cycles of hash access")
     max_miss_count = Param.Counter(0,
         "number of misses to handle before calling exit")
     mshrs = Param.Int("number of MSHRs (max outstanding requests)")

src/mem/cache/tags/iic.cc

@@ -250,6 +250,8 @@ IIC::accessBlock(Addr addr, int &lat, int context_src)
         }
 
     }
+    // @todo: is hashDelay is really cycles, then
+    // multiply with period
     set_lat = set_lat * hashDelay + hitLatency;
     if (tag_ptr != NULL) {
         // IIC replacement: if this is not the first element of

src/mem/cache/tags/iic.hh

@@ -196,7 +196,7 @@ class IIC : public BaseTags
     const unsigned subMask;
 
     /** The latency of a hash lookup. */
-    const unsigned hashDelay;
+    const Cycles hashDelay;
     /** The total number of tags in primary and secondary. */
     const unsigned numTags;
     /** The number of tags in the secondary tag store. */

src/mem/ruby/system/BankedArray.cc

@@ -36,7 +36,7 @@
 #include "mem/ruby/system/BankedArray.hh"
 #include "sim/eventq.hh"
 
-BankedArray::BankedArray(unsigned int banks, unsigned int accessLatency, unsigned int startIndexBit) :
+BankedArray::BankedArray(unsigned int banks, Cycles accessLatency, unsigned int startIndexBit) :
     EventManager(&mainEventQueue)
 {
     this->banks = banks;

src/mem/ruby/system/BankedArray.hh

@@ -43,7 +43,7 @@ class BankedArray : public EventManager
 {
 private:
     unsigned int banks;
-    unsigned int accessLatency;
+    Cycles accessLatency;
     unsigned int bankBits;
     unsigned int startIndexBit;
 
@@ -66,7 +66,7 @@ private:
     unsigned int mapIndexToBank(Index idx);
 
 public:
-    BankedArray(unsigned int banks, unsigned int accessLatency, unsigned int startIndexBit);
+    BankedArray(unsigned int banks, Cycles accessLatency, unsigned int startIndexBit);
 
     // Note: We try the access based on the cache index, not the address
     // This is so we don't get aliasing on blocks being replaced

src/mem/ruby/system/Cache.py

@@ -43,6 +43,6 @@ class RubyCache(SimObject):
 
     dataArrayBanks = Param.Int(1, "Number of banks for the data array")
     tagArrayBanks = Param.Int(1, "Number of banks for the tag array")
-    dataAccessLatency = Param.Int(1, "Gem5 cycles for the data array")
-    tagAccessLatency = Param.Int(1, "Gem5 cycles for the tag array")
+    dataAccessLatency = Param.Cycles(1, "cycles for a data array access")
+    tagAccessLatency = Param.Cycles(1, "cycles for a tag array access")
     resourceStalls = Param.Bool(False, "stall if there is a resource failure")

src/mem/ruby/system/Sequencer.hh

@@ -139,7 +139,7 @@ class Sequencer : public RubyPort
 
   private:
     int m_max_outstanding_requests;
-    int m_deadlock_threshold;
+    Cycles m_deadlock_threshold;
 
     CacheMemory* m_dataCache_ptr;
     CacheMemory* m_instCache_ptr;

src/mem/ruby/system/Sequencer.py

@@ -58,7 +58,7 @@ class RubySequencer(RubyPort):
     dcache = Param.RubyCache("")
     max_outstanding_requests = Param.Int(16,
         "max requests (incl. prefetches) outstanding")
-    deadlock_threshold = Param.Int(500000,
+    deadlock_threshold = Param.Cycles(500000,
         "max outstanding cycles for a request before deadlock/livelock declared")
 
 class DMASequencer(RubyPort):