From 7bf6a219db91406df91d4e9323b47e6d70ed73fb Mon Sep 17 00:00:00 2001
From: Steve Reinhardt <Steve.Reinhardt@amd.com>
Date: Mon, 29 Sep 2008 23:30:14 -0700
Subject: [PATCH] Make overriding port assignments in Python work, and print
 better error messages when it doesn't.

---
 src/dev/io_device.hh    | 9 ++++++---
 src/python/m5/params.py | 3 +++
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/dev/io_device.hh b/src/dev/io_device.hh
index 1e2e623f1..e18489378 100644
--- a/src/dev/io_device.hh
+++ b/src/dev/io_device.hh
@@ -212,7 +212,8 @@ class PioDevice : public MemObject
     {
         if (if_name == "pio") {
             if (pioPort != NULL)
-                panic("pio port already connected to.");
+                fatal("%s: pio port already connected to %s",
+                      name(), pioPort->getPeer()->name());
             pioPort = new PioPort(this, sys);
             return pioPort;
         } else
@@ -289,12 +290,14 @@ class DmaDevice : public PioDevice
     {
         if (if_name == "pio") {
             if (pioPort != NULL)
-                panic("pio port already connected to.");
+                fatal("%s: pio port already connected to %s",
+                      name(), pioPort->getPeer()->name());
             pioPort = new PioPort(this, sys);
             return pioPort;
         } else if (if_name == "dma") {
             if (dmaPort != NULL)
-                panic("dma port already connected to.");
+                fatal("%s: dma port already connected to %s",
+                      name(), pioPort->getPeer()->name());
             dmaPort = new DmaPort(this, sys);
             return dmaPort;
         } else
diff --git a/src/python/m5/params.py b/src/python/m5/params.py
index 9394b11e2..081bd342e 100644
--- a/src/python/m5/params.py
+++ b/src/python/m5/params.py
@@ -1004,6 +1004,7 @@ class PortRef(object):
         if self.peer and not proxy.isproxy(self.peer):
             print "warning: overwriting port", self, \
                   "value", self.peer, "with", other
+            self.peer.peer = None
         self.peer = other
         if proxy.isproxy(other):
             other.set_param_desc(PortParamDesc())
@@ -1046,6 +1047,8 @@ class PortRef(object):
         if self.ccConnected: # already done this
             return
         peer = self.peer
+        if not self.peer: # nothing to connect to
+            return
         connectPorts(self.simobj.getCCObject(), self.name, self.index,
                      peer.simobj.getCCObject(), peer.name, peer.index)
         self.ccConnected = True
-- 
2.30.2