ruby: no piobus in se mode

Piobus was recently added to se scripts for ruby so that the interrupt
controller can be connected to something (required since the interrupt
controller sends address range messages).  This patch removes the piobus
and instead, the pio port of ruby port will now ignore the range change
messages in se mode.

configs/example/se.py

@@ -232,9 +232,7 @@ if options.ruby:
     system.physmem = MemClass(range=AddrRange(options.mem_size),
                               null = True)
     options.use_map = True
-
-    system.piobus = NoncoherentBus()
-    Ruby.create_system(options, system, system.piobus)
+    Ruby.create_system(options, system)
     assert(options.num_cpus == len(system.ruby._cpu_ruby_ports))
 
     for i in xrange(np):

src/mem/ruby/system/RubyPort.cc

@@ -46,6 +46,7 @@
 #include "mem/protocol/AccessPermission.hh"
 #include "mem/ruby/slicc_interface/AbstractController.hh"
 #include "mem/ruby/system/RubyPort.hh"
+#include "sim/full_system.hh"
 #include "sim/system.hh"
 
 RubyPort::RubyPort(const Params *p)
@@ -558,7 +559,7 @@ RubyPort::PioMasterPort::recvRangeChange()
 {
     RubyPort &r = static_cast<RubyPort &>(owner);
     r.gotAddrRanges--;
-    if (r.gotAddrRanges == 0) {
+    if (r.gotAddrRanges == 0 && FullSystem) {
         r.pioSlavePort.sendRangeChange();
     }
 }

tests/configs/simple-timing-ruby.py

@@ -79,8 +79,7 @@ system.cpu.clk_domain = SrcClockDomain(clock = '2GHz',
                                        voltage_domain = system.voltage_domain)
 
 system.mem_ranges = AddrRange('256MB')
-system.piobus = NoncoherentBus()
-Ruby.create_system(options, system, system.piobus)
+Ruby.create_system(options, system)
 
 # Create a separate clock for Ruby
 system.ruby.clk_domain = SrcClockDomain(clock = options.ruby_clock,