//-----------------------------------------------------------------------------
// V12 Engine
// 
// Copyright (c) 2001 GarageGames.Com
// Portions Copyright (c) 2001 by Sierra Online, Inc.
//-----------------------------------------------------------------------------

#include "platform/platform.h"
#include "platformX86UNIX/platformX86UNIX.h"
#include "console/console.h"
#include "core/stringTable.h"
#include <math.h>

Platform::SystemInfo_struct Platform::SystemInfo;
extern void PlatformBlitInit();

/* used in the asm */
U32 time[2];
U32 clockticks = 0;

void Processor::init()
{
   // Reference:
   //    www.cyrix.com
   //    www.amd.com
   //    www.intel.com
   //       http://developer.intel.com/design/PentiumII/manuals/24512701.pdf
   Platform::SystemInfo.processor.type = CPU_X86Compatible;
   Platform::SystemInfo.processor.name = StringTable->insert("Unknown x86 Compatible");
   Platform::SystemInfo.processor.mhz  = 0;
   Platform::SystemInfo.processor.properties = CPU_PROP_C;

   //--------------------------------------
   // calculate the aproximate Mhz of the CPU
   const U32 MS_INTERVAL = 750;
   __asm__("
       pushl  %eax
       pushl  %edx
       //db    0fh, 31h
       rdtsc
       movl   %eax, (time)
       movl   %edx, (time+4)
       popl   %edx
       popl   %eax
   ");
   U32 ms = Platform::getRealMilliseconds();
   while ( Platform::getRealMilliseconds() < ms+MS_INTERVAL )
   { /* empty */ }
   ms = Platform::getRealMilliseconds()-ms;
   asm("
       pushl  %eax
       pushl  %edx
       //db    0fh, 31h
       rdtsc
       sub    (time+4), %edx
       sbb    (time), %eax
       mov    %eax, (clockticks)
       popl   %edx
       popl   %eax
   ");
   U32 mhz = F32(clockticks) / F32(ms) / 1000.0f;

   // catch-22 the timing method used above to calc Mhz is generally
   // wrong by a few percent so we want to round to the nearest clock
   // multiple but we also want to be careful to not touch overclocked results

   // measure how close the Raw Mhz number is to the center of each clock bucket
   U32 bucket25 = mhz % 25;
   U32 bucket33 = mhz % 33;
   U32 bucket50 = mhz % 50;

   if (bucket50 < 8 || bucket50 > 42)
      Platform::SystemInfo.processor.mhz = U32((mhz+(50.0f/2.0f))/50.0f) * 50; 
   else if (bucket25 < 5 || bucket25 > 20)
      Platform::SystemInfo.processor.mhz = U32((mhz+(25.0f/2.0f))/25.0f) * 25; 
   else if (bucket33 < 5 || bucket33 > 28)
      Platform::SystemInfo.processor.mhz = U32((mhz+(33.0f/2.0f))/33.0f) * 33; 
   else 
      Platform::SystemInfo.processor.mhz = U32(mhz); 

   Con::printf("Processor Init:");
   Con::printf("   %s, %d Mhz", Platform::SystemInfo.processor.name, Platform::SystemInfo.processor.mhz);
   if (Platform::SystemInfo.processor.properties & CPU_PROP_FPU)
      Con::printf("   FPU detected");
   if (Platform::SystemInfo.processor.properties & CPU_PROP_MMX)
      Con::printf("   MMX detected");
   if (Platform::SystemInfo.processor.properties & CPU_PROP_3DNOW)
      Con::printf("   3DNow detected");
   if (Platform::SystemInfo.processor.properties & CPU_PROP_SSE)
      Con::printf("   SSE detected");
   Con::printf(" ");

   PlatformBlitInit();
}