Initial commit of OpenSPARC T2 architecture model.

[OpenSPARC-T2-SAM] / sam-t2 / sam / cpus / vonk / ss / api / pli / src / SS_TimedTlb.cc

// ========== Copyright Header Begin ==========================================
// 
// OpenSPARC T2 Processor File: SS_TimedTlb.cc
// Copyright (c) 2006 Sun Microsystems, Inc.  All Rights Reserved.
// DO NOT ALTER OR REMOVE COPYRIGHT NOTICES.
// 
// The above named program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public
// License version 2 as published by the Free Software Foundation.
// 
// The above named program is distributed in the hope that it will be 
// useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// General Public License for more details.
// 
// You should have received a copy of the GNU General Public
// License along with this work; if not, write to the Free Software
// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
// 
// ========== Copyright Header End ============================================

#include <stdio.h>
#include <stdlib.h>
#include "SS_TimedTlb.h"

SS_TimedTlb::SS_TimedTlb( SS_Tlb* _tlb, uint_t _upper_size )/*{{{*/
 :
  latest_time(0), 
  latest_tlb(_tlb),
  upper_size(_upper_size),
  socket(NULL)
{
  tlb[latest_time] = latest_tlb;
}
/*}}}*/
SS_Tlb* SS_TimedTlb::modify( uint32_t time )/*{{{*/
{
  if (latest_time < time)
  {
    tlb[time] = latest_tlb = (latest_tlb->clone)(latest_tlb); 
    latest_time = time;
  }
  else if (latest_time > time)
  {
    // If we hit this assertion then we have an inconsistancy. Somehow we ended up with
    // a tlb at modification times t1 and t2 and we get asked to create a tlb with a 
    // modification time tx such that t1 < tx < t2. Hence that would mean modification
    // caused by tx should propagate to t2 and higher meaning that we used a wrong tlb
    // earlier. So I think this should never occur. Hence bail out.
    char buffer[256];
    sprintf(buffer, "ERROR: TLB modification time violation: last tlb_write_time=%d >= new tlb_write_time=%d",latest_time,time);
    fprintf(stderr,"%s\n", buffer);
    if (socket)
    {
      socket->write_err(buffer);
      // if pli-socket condition is bad, we should not process pli commands any further
      socket->pli_stop();
    }
  }

  // Keep the number of TLBs that we keep around under an upper limit
  // as they can eat quite some memory over time.
 
  while (tlb.size() >= upper_size)
  {
    std::map<uint32_t,SS_Tlb*,Cmp>::reverse_iterator i = tlb.rbegin();
    delete (*i).second;
    tlb.erase((*i).first);
  }
  
  return latest_tlb;
}
/*}}}*/


SS_Tlb* SS_TimedTlb::lookup( uint32_t time )				
{ 
  for (std::map<uint32_t,SS_Tlb*,Cmp>::iterator i = tlb.begin(); i != tlb.end(); i++)
    if (time >= (*i).first)
      if ((*i).second)
	return (*i).second;
      else
      {
        char buffer[256];
        sprintf(buffer, "INTERNAL ERROR: SS_TimedTlb lookup time got deleted, max size=%d", upper_size);
	fprintf(stderr,"%s\n",buffer);
        if (socket)
        {
          socket->write_err(buffer);
          // if pli-socket condition is bad, we should not process pli commands any further
          socket->pli_stop();
        }
      }

  // The above should always succeed as we insert the initial tlb with time stamp 0.

  char buffer[256];
  sprintf(buffer, "INTERNAL ERROR: SS_TimedTlb lookup time (%d) not matched, max size=%d", time, upper_size);
  fprintf(stderr,"%s\n",buffer);
  if (socket)
  {
    socket->write_err(buffer);
    // if pli-socket condition is bad, we should not process pli commands any further
    socket->pli_stop();
  }
  return 0; 
}