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/*
* Copyright (c) 2001-2005 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Authors: Nathan Binkert
*/
/** @file
* System Console Backdoor Interface
*/
#ifndef __DEV_ALPHA_BACKDOOR_HH__
#define __DEV_ALPHA_BACKDOOR_HH__
#include "base/types.hh"
#include "dev/alpha/access.h"
#include "dev/io_device.hh"
#include "params/AlphaBackdoor.hh"
#include "sim/sim_object.hh"
class BaseCPU;
class Terminal;
class AlphaSystem;
class SimpleDisk;
/**
* Memory mapped interface to the system console. This device
* represents a shared data region between the OS Kernel and the
* System Console Backdoor.
*
* The system console is a small standalone program that is initially
* run when the system boots. It contains the necessary code to
* access the boot disk, to read/write from the console, and to pass
* boot parameters to the kernel.
*
* This version of the system console is very different from the one
* that would be found in a real system. Many of the functions use
* some sort of backdoor to get their job done. For example, reading
* from the boot device on a real system would require a minimal
* device driver to access the disk controller, but since we have a
* simulator here, we are able to bypass the disk controller and
* access the disk image directly. There are also some things like
* reading the kernel off the disk image into memory that are normally
* taken care of by the console that are now taken care of by the
* simulator.
*
* These shortcuts are acceptable since the system console is
* primarily used doing boot before the kernel has loaded its device
* drivers.
*/
class AlphaBackdoor : public BasicPioDevice
{
protected:
struct Access : public AlphaAccess
{
void serialize(std::ostream &os);
void unserialize(Checkpoint *cp, const std::string &section);
};
union {
Access *alphaAccess;
uint8_t *consoleData;
};
/** the disk must be accessed from the console */
SimpleDisk *disk;
/** the system console (the terminal) is accessable from the console */
Terminal *terminal;
/** a pointer to the system we are running in */
AlphaSystem *system;
/** a pointer to the CPU boot cpu */
BaseCPU *cpu;
public:
typedef AlphaBackdoorParams Params;
AlphaBackdoor(const Params *p);
const Params *
params() const
{
return dynamic_cast<const Params *>(_params);
}
virtual void startup();
/**
* memory mapped reads and writes
*/
virtual Tick read(PacketPtr pkt);
virtual Tick write(PacketPtr pkt);
/**
* standard serialization routines for checkpointing
*/
virtual void serialize(std::ostream &os);
virtual void unserialize(Checkpoint *cp, const std::string &section);
};
#endif // __DEV_ALPHA_BACKDOOR_HH__