From 06a8a473222c870ac9313d6e1eae807ba338e8d7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tiago=20M=C3=BCck?= <tiago.muck@arm.com>
Date: Thu, 17 Jun 2021 15:06:43 -0500
Subject: [PATCH] configs: fix CHI mem buffers
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Disabling randomization for the memory request and response buffers.
CHI requires that memory responses for the same address arrive in
the same order the request was sent.

Change-Id: Ia4236188679beaf2969978675414a870ccd9f94a
Signed-off-by: Tiago Mück <tiago.muck@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/63673
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
---
 configs/ruby/CHI_config.py                         | 14 ++++++++++++--
 .../chi/nodes/memory_controller.py                 | 14 ++++++++++++--
 2 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/configs/ruby/CHI_config.py b/configs/ruby/CHI_config.py
index a95efec16f..25d4f0575e 100644
--- a/configs/ruby/CHI_config.py
+++ b/configs/ruby/CHI_config.py
@@ -183,6 +183,16 @@ class OrderedTriggerMessageBuffer(TriggerMessageBuffer):
     ordered = True
 
 
+class MemCtrlMessageBuffer(MessageBuffer):
+    """
+    MessageBuffer exchanging messages with the memory
+    These buffers should also not be affected by the Ruby tester randomization.
+    """
+
+    randomization = "disabled"
+    ordered = True
+
+
 class CHI_Cache_Controller(Cache_Controller):
     """
     Default parameters for a Cache controller
@@ -667,8 +677,8 @@ class CHI_SNF_Base(CHI_Node):
             version=Versions.getVersion(Memory_Controller),
             ruby_system=ruby_system,
             triggerQueue=TriggerMessageBuffer(),
-            responseFromMemory=MessageBuffer(),
-            requestToMemory=MessageBuffer(ordered=True),
+            responseFromMemory=MemCtrlMessageBuffer(),
+            requestToMemory=MemCtrlMessageBuffer(),
             reqRdy=TriggerMessageBuffer(),
             transitions_per_cycle=1024,
         )
diff --git a/src/python/gem5/components/cachehierarchies/chi/nodes/memory_controller.py b/src/python/gem5/components/cachehierarchies/chi/nodes/memory_controller.py
index 4d0589499d..bee5e8887f 100644
--- a/src/python/gem5/components/cachehierarchies/chi/nodes/memory_controller.py
+++ b/src/python/gem5/components/cachehierarchies/chi/nodes/memory_controller.py
@@ -37,6 +37,16 @@ from m5.objects import (
 from .abstract_node import TriggerMessageBuffer
 
 
+class MemCtrlMessageBuffer(MessageBuffer):
+    """
+    MessageBuffer exchanging messages with the memory
+    These buffers should also not be affected by the Ruby tester randomization.
+    """
+
+    randomization = "disabled"
+    ordered = True
+
+
 class MemoryController(Memory_Controller):
     """A controller that connects to memory"""
 
@@ -62,8 +72,8 @@ class MemoryController(Memory_Controller):
 
     def connectQueues(self, network):
         self.triggerQueue = TriggerMessageBuffer()
-        self.responseFromMemory = MessageBuffer()
-        self.requestToMemory = MessageBuffer(ordered=True)
+        self.responseFromMemory = MemCtrlMessageBuffer()
+        self.requestToMemory = MemCtrlMessageBuffer()
         self.reqRdy = TriggerMessageBuffer()
 
         self.reqOut = MessageBuffer()