cpu: Consolidate and move the CPU's calls to TheISA::initCPU.

TheISA::initCPU is basically an ISA specific implementation of reset
logic on architectural state. As such, it only needs to be called if
we're not going to load a checkpoint, ie in initState.

Also, since the implementation was the same across all CPUs, this
change collapses all the individual implementations down into the base
CPU class.

Change-Id: Id68133fd7f31619c90bf7b3aad35ae20871acaa4
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/24189
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
diff --git a/src/cpu/base.cc b/src/cpu/base.cc
index ac0c7ac..5d6a857 100644
--- a/src/cpu/base.cc
+++ b/src/cpu/base.cc
@@ -321,6 +321,15 @@
 }
 
 void
+BaseCPU::initState()
+{
+    if (FullSystem && !params()->switched_out) {
+        for (auto *tc: threadContexts)
+            TheISA::initCPU(tc, tc->contextId());
+    }
+}
+
+void
 BaseCPU::startup()
 {
     if (FullSystem) {
diff --git a/src/cpu/base.hh b/src/cpu/base.hh
index 5b15f41..f47bc8e 100644
--- a/src/cpu/base.hh
+++ b/src/cpu/base.hh
@@ -314,6 +314,7 @@
     virtual ~BaseCPU();
 
     void init() override;
+    void initState() override;
     void startup() override;
     void regStats() override;
 
diff --git a/src/cpu/kvm/base.cc b/src/cpu/kvm/base.cc
index 83cb04f..cda98b4 100644
--- a/src/cpu/kvm/base.cc
+++ b/src/cpu/kvm/base.cc
@@ -114,10 +114,6 @@
         fatal("KVM: Multithreading not supported");
 
     tc->initMemProxies(tc);
-
-    // initialize CPU, including PC
-    if (FullSystem && !switchedOut())
-        TheISA::initCPU(tc, tc->contextId());
 }
 
 void
diff --git a/src/cpu/minor/cpu.cc b/src/cpu/minor/cpu.cc
index ddba0cd..5edc570 100644
--- a/src/cpu/minor/cpu.cc
+++ b/src/cpu/minor/cpu.cc
@@ -108,17 +108,6 @@
 
         tc->initMemProxies(tc);
     }
-
-    /* Initialise CPUs (== threads in the ISA) */
-    if (FullSystem && !params()->switched_out) {
-        for (ThreadID thread_id = 0; thread_id < threads.size(); thread_id++)
-        {
-            ThreadContext *tc = getContext(thread_id);
-
-            /* Initialize CPU, including PC */
-            TheISA::initCPU(tc, cpuId());
-        }
-    }
 }
 
 /** Stats interface from SimObject (by way of BaseCPU) */
diff --git a/src/cpu/o3/cpu.cc b/src/cpu/o3/cpu.cc
index 996f636..e4f1c04 100644
--- a/src/cpu/o3/cpu.cc
+++ b/src/cpu/o3/cpu.cc
@@ -599,13 +599,6 @@
         thread[tid]->initMemProxies(thread[tid]->getTC());
     }
 
-    if (FullSystem && !params()->switched_out) {
-        for (ThreadID tid = 0; tid < numThreads; tid++) {
-            ThreadContext *src_tc = threadContexts[tid];
-            TheISA::initCPU(src_tc, src_tc->contextId());
-        }
-    }
-
     // Clear noSquashFromTC.
     for (int tid = 0; tid < numThreads; ++tid)
         thread[tid]->noSquashFromTC = false;
diff --git a/src/cpu/simple/base.cc b/src/cpu/simple/base.cc
index 566533c..06dd773 100644
--- a/src/cpu/simple/base.cc
+++ b/src/cpu/simple/base.cc
@@ -130,11 +130,6 @@
     for (auto tc : threadContexts) {
         // Initialise the ThreadContext's memory proxies
         tc->initMemProxies(tc);
-
-        if (FullSystem && !params()->switched_out) {
-            // initialize CPU, including PC
-            TheISA::initCPU(tc, tc->contextId());
-        }
     }
 }