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// 
// OpenSPARC T2 Processor File: FNXRandomUtil.vr
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#include "FNXRandomUtilDefines.vri"
#include "report_macros.vri"
#include "cReport.vrh"

class FNXRandomUtil {

  ReportClass Report;

  task new( ReportClass Report );

  // Generates a random 32-bit unsigned number between min and max
  function bit [31:0] Rand32 ( bit [31:0] min = 0,
			       bit [31:0] max = FNX_UTIL_MAX_32_BIT_UNSIGNED_VAL ); 
  
  // Generates a random 64-bit unsigned number between min and max
  function bit [63:0] Rand64 ( bit [63:0] min = 0, 
			       bit [63:0] max = FNX_UTIL_MAX_64_BIT_UNSIGNED_VAL );
  
  // Generates a random 96-bit unsigned number between min and max
  function bit [95:0] Rand96 ( bit [95:0] min = 0, 
			       bit [95:0] max = FNX_UTIL_MAX_96_BIT_UNSIGNED_VAL );
  
  // Generates a random 128-bit unsigned number between min and max
  function bit [127:0] Rand128 ( bit [127:0] min = 0, 
				 bit [127:0] max = FNX_UTIL_MAX_128_BIT_UNSIGNED_VAL );

  // Set The Random Seed. Default will be set with Time of Day
  task SetSeed( bit [31:0] RandSeed = get_systime() );

  // Set Random Seed with the Time of Day
  task SeedWithTOD();
}

task FNXRandomUtil::new ( ReportClass Report ) {
  this.Report = Report;
}

function bit [31:0] FNXRandomUtil::Rand32 ( bit [31:0] min = 0,
					    bit [31:0] max = FNX_UTIL_MAX_32_BIT_UNSIGNED_VAL ) 
{
  bit [31:0] divisor;

  if (max >= min) {
    if ((max - min) == FNX_UTIL_MAX_32_BIT_UNSIGNED_VAL) {
      Rand32 = urandom();
    } 
    else {
      Rand32 = (urandom() % (max-min+1)) + min;
    }
  } else {
    Rand32 = min;
  }
  
}

function bit [63:0] FNXRandomUtil::Rand64 ( bit [63:0] min = 0, 
					    bit [63:0] max = FNX_UTIL_MAX_64_BIT_UNSIGNED_VAL)
{  
  if (max >= min) {  
    if ((max - min) == FNX_UTIL_MAX_64_BIT_UNSIGNED_VAL) {
      Rand64 = {urandom(), urandom()};
    } 
    else {
      Rand64 = ({urandom(), urandom()} % (max-min+1)) + min;
    }
  } else {
    Rand64 = min;
  }
}

function bit [95:0] FNXRandomUtil::Rand96 ( bit [95:0] min = 0, 
					    bit [95:0] max = FNX_UTIL_MAX_96_BIT_UNSIGNED_VAL )
{  
  if (max >= min) {  
    if ((max - min) == FNX_UTIL_MAX_96_BIT_UNSIGNED_VAL) {
      Rand96 = {urandom(), urandom(), urandom()};
    } 
    else {
      Rand96 = ({urandom(), urandom(), urandom()} % (max-min+1)) + min;
    }
  } else {
    Rand96 = min;
  }
}

function bit [127:0] FNXRandomUtil::Rand128 ( bit [127:0] min = 0, 
					      bit [127:0] max = FNX_UTIL_MAX_128_BIT_UNSIGNED_VAL )
{  
  if (max >= min) {  
    if ((max - min) == FNX_UTIL_MAX_128_BIT_UNSIGNED_VAL) {
      Rand128 = {urandom(), urandom(), urandom(), urandom()};
    } 
    else {
      Rand128 = ({urandom(), urandom(), urandom(), urandom()} % (max-min+1)) + min;
    }
  } else {
    Rand128 = min;
  }
}

task FNXRandomUtil::SetSeed( bit [31:0] RandSeed = get_systime() )
{
  urandom(RandSeed);
  QuickReport( Report,
	       RTYP_INFO,
	       "FNXRandomUtil::SetSeed(): urandom() seed set to %0h", 
	       RandSeed );
}

task FNXRandomUtil::SeedWithTOD()
{
  bit [31:0] time_0, urand_seed;
  
  time_0 = get_systime();
  urandom(time_0);
  urand_seed = time_0 + urandom();
  urandom(urand_seed);
  
  QuickReport( Report,  
	       RTYP_INFO,
	       "FNXRandomUtil::SeedWithTOD(): urandom() seeded with time of day, seed=%h", 
	       urand_seed );
}