SE/FS: Remove System::platform and Platform::intrFrequency.

In order for a system object to work in SE mode and FS mode, it has to either
always require a platform object even in SE mode, or get rid of the
requirement all together. Making SE mode carry around unnecessary/unused bits
of FS seems less than ideal, so I decided to go with the second option. The
platform pointer in the System class was used for exactly one purpose, a path
for the Alpha Linux system object to get to the real time clock and read its
frequency so that it could short cut the loops_per_jiffy calculation. There
was also a copy and pasted implementation in MIPS, but since it was only there
because it was there in Alpha I still count that as one use.

This change reverses the mechanism that communicates the RTC frequency so that
the Tsunami platform object pushes it up to the AlphaSystem object. This is
slightly less specific than it could be because really only the
AlphaLinuxSystem uses it. Because the intrFrequency function on the Platform
class was no longer necessary (and unimplemented on anything but Alpha) it was
eliminated.

After this change, a platform will need to have a system, but a system won't
have to have a platform.

3 files changed, 21 insertions, 16 deletions

diff --git a/src/dev/alpha/backdoor.cc b/src/dev/alpha/backdoor.cc
index 4d9d046de..1c5bb5f54 100644
--- a/src/dev/alpha/backdoor.cc
+++ b/src/dev/alpha/backdoor.cc
@@ -50,6 +50,9 @@
 #include "cpu/thread_context.hh"
 #include "debug/AlphaBackdoor.hh"
 #include "dev/alpha/backdoor.hh"
+#include "dev/alpha/tsunami.hh"
+#include "dev/alpha/tsunami_cchip.hh"
+#include "dev/alpha/tsunami_io.hh"
 #include "dev/platform.hh"
 #include "dev/simple_disk.hh"
 #include "dev/terminal.hh"
@@ -99,7 +102,9 @@ AlphaBackdoor::startup()
     alphaAccess->entryPoint = system->getKernelEntry();
     alphaAccess->mem_size = system->physmem->size();
     alphaAccess->cpuClock = cpu->frequency() / 1000000; // In MHz
-    alphaAccess->intrClockFrequency = params()->platform->intrFrequency();
+    Tsunami *tsunami = dynamic_cast<Tsunami *>(params()->platform);
+    assert(tsunami);
+    alphaAccess->intrClockFrequency = tsunami->io->frequency();
 #endif
 }
 
diff --git a/src/dev/alpha/tsunami.cc b/src/dev/alpha/tsunami.cc
index 16e2bfb28..65154c7d8 100644
--- a/src/dev/alpha/tsunami.cc
+++ b/src/dev/alpha/tsunami.cc
@@ -36,6 +36,12 @@
 #include <string>
 #include <vector>
 
+#include "config/full_system.hh"
+
+#if FULL_SYSTEM //XXX AlphaSystem doesn't build in SE mode yet.
+#include "arch/alpha/system.hh"
+#endif
+
 #include "config/the_isa.hh"
 #include "cpu/intr_control.hh"
 #include "dev/alpha/tsunami.hh"
@@ -43,7 +49,6 @@
 #include "dev/alpha/tsunami_io.hh"
 #include "dev/alpha/tsunami_pchip.hh"
 #include "dev/terminal.hh"
-#include "sim/system.hh"
 
 using namespace std;
 //Should this be AlphaISA?
@@ -52,19 +57,18 @@ using namespace TheISA;
 Tsunami::Tsunami(const Params *p)
     : Platform(p), system(p->system)
 {
-#if FULL_SYSTEM //XXX No platform pointer in SE mode.
-    // set the back pointer from the system to myself
-    system->platform = this;
-#endif
-
     for (int i = 0; i < Tsunami::Max_CPUs; i++)
         intr_sum_type[i] = 0;
 }
 
-Tick
-Tsunami::intrFrequency()
+void
+Tsunami::init()
 {
-    return io->frequency();
+#if FULL_SYSTEM //XXX AlphaSystem doesn't build in SE mode yet.
+    AlphaSystem *alphaSystem = dynamic_cast<AlphaSystem *>(system);
+    assert(alphaSystem);
+    alphaSystem->setIntrFreq(io->frequency());
+#endif
 }
 
 void
diff --git a/src/dev/alpha/tsunami.hh b/src/dev/alpha/tsunami.hh
index 64aafe533..9380864b0 100644
--- a/src/dev/alpha/tsunami.hh
+++ b/src/dev/alpha/tsunami.hh
@@ -80,17 +80,13 @@ class Tsunami : public Platform
     int intr_sum_type[Tsunami::Max_CPUs];
     int ipi_pending[Tsunami::Max_CPUs];
 
+    void init();
+
   public:
     typedef TsunamiParams Params;
     Tsunami(const Params *p);
 
     /**
-     * Return the interrupting frequency to AlphaAccess
-     * @return frequency of RTC interrupts
-     */
-    virtual Tick intrFrequency();
-
-    /**
      * Cause the cpu to post a serial interrupt to the CPU.
      */
     virtual void postConsoleInt();