/********************************************************************** <BR>
  This file is part of Crack dot Com's free source code release of
  Golgotha. <a href="http://www.crack.com/golgotha_release"> <BR> for
  information about compiling & licensing issues visit this URL</a> 
  <PRE> If that doesn't help, contact Jonathan Clark at 
  golgotha_source@usa.net (Subject should have "GOLG" in it) 
***********************************************************************/

#include "device/processor.hh"
#include <string.h>

w32 x86_can_do_cpuid()
{
  w32 result;

  _asm
  {
    pushfd                          //save EFLAGS
    
    pop  eax
    test eax,0x00200000   //check ID bit (bit 21)
    jz   set_21           //bit 21 is not set, so jump to set_21
    and  eax,0xffdfffff  //clear bit 21
    push eax            //save new value in register
    
    popfd                         //store new value in flags
    pushfd
    
    pop  eax
    test eax,0x00200000 //check ID bit
    
    jnz  cpu_id_not_ok      //if bit 21 isnt clear,then jump to cpu_id_not_ok
    
    mov  dword ptr [result],1 // return 1
    jmp  done

set_21:
    or   eax,0x00200000  //set bit 21
    push eax             //store new value
    
    popfd                          //store new value in EFLAGS
    pushfd
    
    pop  eax
    test eax,0x00200000  //if bit 21 is on
    jz   cpu_id_not_ok       //then jump to cpu_id_ok
    
    mov  dword ptr [result],1 // return 1
		jmp  done

cpu_id_not_ok:

    mov  dword ptr [result],0 //CPUID inst is not supported

done:
  }

  return result;
}

w32 x86_get_cpu_type()
{
  char name[32];

  _asm
  {
    mov eax,0
    
    __emit 0x0F //cpuid
    __emit 0xA2
    
    //store it
    mov byte ptr [name],bl
    mov byte ptr [name+1],bh
    
    ror ebx, 16

    mov byte ptr [name+2],bl
    mov byte ptr [name+3],bh
    mov byte ptr [name+4],dl
    mov byte ptr [name+5],dh
  
    ror edx,16
  
    mov byte ptr [name+6],dl
    mov byte ptr [name+7],dh
    mov byte ptr [name+8],cl
    mov byte ptr [name+9],ch

    ror ecx,16

    mov byte ptr [name+10],cl
    mov byte ptr [name+11],ch
    mov byte ptr [name+12],0
  }

  if (!strcmp(name,"AuthenticAMD") || !strcmp(name,"CentaurHauls"))
    return i4_cpu_info_struct::AMD_X86;
  else
  if (!strcmp(name,"GenuineIntel"))
    return i4_cpu_info_struct::INTEL_X86;
  else
    return i4_cpu_info_struct::UNKNOWN_X86;
}

w32 x86_get_cpu_flags(w32 cpu_type)
{
  unsigned int processor_sig;
  unsigned int extended_flags;

  _asm
  {
		 mov eax,0x80000001 //the cpuid function we're requesting
		 
     __emit 0x0F
     __emit 0xA2 //cpuid

     mov dword ptr [processor_sig],eax
     mov dword ptr [extended_flags],edx
  }
  
  //perhaps check the processor signature too?

  w32 flags = 0;

  if (cpu_type==i4_cpu_info_struct::AMD_X86)
  {
    if (extended_flags & (1<<4))
      flags |= i4_cpu_info_struct::RDTSC;

    if (extended_flags & (23<<31))
      flags |= i4_cpu_info_struct::MMX;

    if (extended_flags & (1<<31))
      flags |= i4_cpu_info_struct::AMD3D;
  }
  else
  if (cpu_type==i4_cpu_info_struct::INTEL_X86)
  {
    if (extended_flags & (1<<4))
      flags |= i4_cpu_info_struct::RDTSC;

    /*
    if (extended_flags & (23<<31))
      flags |= i4_cpu_info_struct::MMX;

    if (extended_flags & (1<<31))
      flags |= i4_cpu_info_struct::AMD3D;
    */
  }
    
  return flags;
}

void i4_win32_get_cpu_info(i4_cpu_info_struct *s)
{
  _asm pusha

  if (!x86_can_do_cpuid())
  {
    s->cpu_type  = i4_cpu_info_struct::UNKNOWN_X86;
    s->cpu_flags = 0;
  }
  else
  {
    s->cpu_type  = x86_get_cpu_type();
    s->cpu_flags = x86_get_cpu_flags(s->cpu_type);
  }
  _asm popa
}