sam-t2/sam/cpus/vonk/ss/lib/cpu/src/SS_Signal.h

/*
* ========== Copyright Header Begin ==========================================
*
* OpenSPARC T2 Processor File: SS_Signal.h
* 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 ============================================
*/
#ifndef __SS_Signal_h__
#define __SS_Signal_h__

#include "BL_Mutex.h"
#include "SS_BreakPoint.h"
#include "SS_Tte.h"
#include "SS_Trap.h"

class SS_Tlb;
class SS_Strand;

class SS_Signal
{
  public:
    // The Type are the signal types used in Vonk to tell a
    // strand to do something before the next instruction

    enum Type
    {
      FREE,                     // Explict free signal
      RUNNING,                  // Change in running status of the strand
      FLUSH_TTE,                // Tell the strand to remove cached TTE from decode cache
      FLUSH_VA,                 // Tell the strand to flush the opcode(2) (64 bit) at given va
      FLUSH_8B,                 // Tell the strand to flush 8 bytes at given pa
      FLUSH_8K,                 // Tell the strand to flush an 8k page at given pa
      FLUSH_ALL,                // Tell the strand to flush  the whole Icache (decode cache)
      BREAKPOINT,               // Tell the strand it hit a breakpoint
      EXTERNAL_INTERRUPT,       // An external interrupt (cross call, dev mondo, ..)
      SET_INST_BRKPT            // Update sim_state.ib_enabled(x)
    };

    SS_Signal( Type t ) : type(t), next(0) {}

    void init( Type t, SS_Signal* n=0 ) { type =t; next = n; }

    Type       type;
    SS_Signal* next;                    // Link the signals in a list

    union
    {
      bool           running;           // New running status
      bool           ib_enable;         // New inst breakpoint check status
      SS_BreakPoint* breakpoint;        // The breakpoint that hit
      int_t          irq_type;          // The (trap) type of the interrupt
      SS_Tte*        tte;               // The TTE to demap from decode cache, 0 is all TTEs
      SS_Vaddr       flush_va;          // The va of the double word to flush from the icache
      SS_Paddr       flush_pa;          // The va of the double word to flush from the icache
    };
    union
    {
      SS_Tlb*        tlb;               // Flush tte flush from which tlb
      bool           irq_raise;         // True raise irq, False retract irq
    };

    void dump();

    static SS_Signal* free_list;
    static BL_Mutex   free_mutex;

    static SS_Signal* alloc_block();
    static const uint_t NR_BLOCK_SIGNAL = 256;


    // alloc() returns a SS_Signal instance with type set to type.
    // Don't use this function if you have direct access to a SS_Strand.
    // Use s->msg.make_signal(type) if you can.

    inline static SS_Signal* alloc( SS_Signal::Type type )
    {
      free_mutex.lock();
      SS_Signal* help = free_list;
      if (help == 0)
        help = alloc_block();
      else
        free_list = help->next;
      free_mutex.unlock();
      help->init(type);
      return help;
    }

    // frees a list of SS_Signal blocks
    // All elements of the list to free must be marked as type=FREE.
    inline static void list_free( SS_Signal* head, SS_Signal* tail )
    {
      free_mutex.lock();
      tail->next = free_list;
      free_list = head;
      free_mutex.unlock();
    }
};

#endif