mem-ruby: Support atomic_noncaching acceses in ruby

Ruby has no support for atomic_noncaching accesses, which prevents using
it with kvm-cpu. This patch fixes this by directly forwarding atomic
requests from the ruby port/sequencer to the corresponding directory
based on the destination address of the packet.

Change-Id: I0b4928bfda44fd9e5e48583c51d1ea422800da2d
Reviewed-on: https://gem5-review.googlesource.com/5601
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Bradford Beckmann <brad.beckmann@amd.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Bradford Beckmann <brad.beckmann@amd.com>

3 files changed, 7 insertions, 12 deletions

diff --git a/configs/common/Simulation.py b/configs/common/Simulation.py
index 71a982af9..7c949b972 100644
--- a/configs/common/Simulation.py
+++ b/configs/common/Simulation.py
@@ -83,6 +83,11 @@ def setCPUClass(options):
         TmpClass = AtomicSimpleCPU
         test_mem_mode = 'atomic'
 
+    # Ruby only supports atomic accesses in noncaching mode
+    if test_mem_mode == 'atomic' and options.ruby:
+        warn("Memory mode will be changed to atomic_noncaching")
+        test_mem_mode = 'atomic_noncaching'
+
     return (TmpClass, test_mem_mode, CPUClass)
 
 def setMemClass(options):
diff --git a/configs/example/fs.py b/configs/example/fs.py
index 65079372c..351d1c016 100644
--- a/configs/example/fs.py
+++ b/configs/example/fs.py
@@ -47,7 +47,7 @@ import sys
 import m5
 from m5.defines import buildEnv
 from m5.objects import *
-from m5.util import addToPath, fatal
+from m5.util import addToPath, fatal, warn
 
 addToPath('../')
 
@@ -147,12 +147,6 @@ def build_test_system(np):
         test_sys.kvm_vm = KvmVM()
 
     if options.ruby:
-        # Check for timing mode because ruby does not support atomic accesses
-        if not (options.cpu_type == "DerivO3CPU" or
-                options.cpu_type == "TimingSimpleCPU"):
-            print >> sys.stderr, "Ruby requires TimingSimpleCPU or O3CPU!!"
-            sys.exit(1)
-
         Ruby.create_system(options, True, test_sys, test_sys.iobus,
                            test_sys._dma_ports)
 
diff --git a/configs/example/se.py b/configs/example/se.py
index 7a19e5aef..56e4753b9 100644
--- a/configs/example/se.py
+++ b/configs/example/se.py
@@ -49,7 +49,7 @@ import os
 import m5
 from m5.defines import buildEnv
 from m5.objects import *
-from m5.util import addToPath, fatal
+from m5.util import addToPath, fatal, warn
 
 addToPath('../')
 
@@ -250,10 +250,6 @@ for i in xrange(np):
     system.cpu[i].createThreads()
 
 if options.ruby:
-    if options.cpu_type == "AtomicSimpleCPU":
-        print >> sys.stderr, "Ruby does not work with atomic cpu!!"
-        sys.exit(1)
-
     Ruby.create_system(options, False, system)
     assert(options.num_cpus == len(system.ruby._cpu_ports))