src/cpu/exec_context.hh - public/gem5 - Git at Google

 /*
  * Copyright (c) 2014, 2016-2018, 2020-2021 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
  * not be construed as granting a license to any other intellectual
  * property including but not limited to intellectual property relating
  * to a hardware implementation of the functionality of the software
  * licensed hereunder.  You may use the software subject to the license
  * terms below provided that you ensure that this notice is replicated
  * unmodified and in its entirety in all distributions of the software,
  * modified or unmodified, in source code or in binary form.
  *
  * Copyright (c) 2002-2005 The Regents of The University of Michigan
  * Copyright (c) 2015 Advanced Micro Devices, Inc.
  * 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.
  */

 #ifndef __CPU_EXEC_CONTEXT_HH__
 #define __CPU_EXEC_CONTEXT_HH__

 #include "base/types.hh"
 #include "cpu/base.hh"
 #include "cpu/reg_class.hh"
 #include "cpu/static_inst_fwd.hh"
 #include "cpu/translation.hh"
 #include "mem/request.hh"

 namespace gem5
 {

 /**
  * The ExecContext is an abstract base class the provides the
  * interface used by the ISA to manipulate the state of the CPU model.
  *
  * Register accessor methods in this class typically provide the index
  * of the instruction's operand (e.g., 0 or 1), not the architectural
  * register index, to simplify the implementation of register
  * renaming.  The architectural register index can be found by
  * indexing into the instruction's own operand index table.
  *
  * @note The methods in this class typically take a raw pointer to the
  * StaticInst is provided instead of a ref-counted StaticInstPtr to
  * reduce overhead as an argument. This is fine as long as the
  * implementation doesn't copy the pointer into any long-term storage
  * (which is pretty hard to imagine they would have reason to do).
  */
 class ExecContext
 {
   public:

     virtual RegVal getRegOperand(const StaticInst *si, int idx) = 0;
     virtual void getRegOperand(const StaticInst *si, int idx, void *val) = 0;
     virtual void *getWritableRegOperand(const StaticInst *si, int idx) = 0;
     virtual void setRegOperand(const StaticInst *si, int idx, RegVal val) = 0;
     virtual void setRegOperand(const StaticInst *si, int idx,
             const void *val) = 0;

     /**
      * @{
      * @name Misc Register Interfaces
      */
     virtual RegVal readMiscRegOperand(const StaticInst *si, int idx) = 0;
     virtual void setMiscRegOperand(const StaticInst *si,
                                    int idx, RegVal val) = 0;

     /**
      * Reads a miscellaneous register, handling any architectural
      * side effects due to reading that register.
      */
     virtual RegVal readMiscReg(int misc_reg) = 0;

     /**
      * Sets a miscellaneous register, handling any architectural
      * side effects due to writing that register.
      */
     virtual void setMiscReg(int misc_reg, RegVal val) = 0;

     /** @} */

     /**
      * @{
      * @name PC Control
      */
     virtual const PCStateBase &pcState() const = 0;
     virtual void pcState(const PCStateBase &val) = 0;
     /** @} */

     /**
      * @{
      * @name Memory Interface
      */
     /**
      * Perform an atomic memory read operation.  Must be overridden
      * for exec contexts that support atomic memory mode.  Not pure
      * virtual since exec contexts that only support timing memory
      * mode need not override (though in that case this function
      * should never be called).
      */
     virtual Fault
     readMem(Addr addr, uint8_t *data, unsigned int size,
             Request::Flags flags, const std::vector<bool>& byte_enable)
     {
         panic("ExecContext::readMem() should be overridden\n");
     }

     /**
      * Initiate a timing memory read operation.  Must be overridden
      * for exec contexts that support timing memory mode.  Not pure
      * virtual since exec contexts that only support atomic memory
      * mode need not override (though in that case this function
      * should never be called).
      */
     virtual Fault
     initiateMemRead(Addr addr, unsigned int size,
             Request::Flags flags, const std::vector<bool>& byte_enable)
     {
         panic("ExecContext::initiateMemRead() should be overridden\n");
     }

     /**
      * Initiate a memory management command with no valid address.
      * Currently, these instructions need to bypass squashing in the O3 model
      * Examples include HTM commands and TLBI commands.
      * e.g. tell Ruby we're starting/stopping a HTM transaction,
      *      or tell Ruby to issue a TLBI operation
      */
     virtual Fault initiateMemMgmtCmd(Request::Flags flags) = 0;

     /**
      * For atomic-mode contexts, perform an atomic memory write operation.
      * For timing-mode contexts, initiate a timing memory write operation.
      */
     virtual Fault writeMem(uint8_t *data, unsigned int size, Addr addr,
                            Request::Flags flags, uint64_t *res,
                            const std::vector<bool>& byte_enable) = 0;

     /**
      * For atomic-mode contexts, perform an atomic AMO (a.k.a., Atomic
      * Read-Modify-Write Memory Operation)
      */
     virtual Fault
     amoMem(Addr addr, uint8_t *data, unsigned int size,
             Request::Flags flags, AtomicOpFunctorPtr amo_op)
     {
         panic("ExecContext::amoMem() should be overridden\n");
     }

     /**
      * For timing-mode contexts, initiate an atomic AMO (atomic
      * read-modify-write memory operation)
      */
     virtual Fault
     initiateMemAMO(Addr addr, unsigned int size, Request::Flags flags,
             AtomicOpFunctorPtr amo_op)
     {
         panic("ExecContext::initiateMemAMO() should be overridden\n");
     }

     /**
      * Sets the number of consecutive store conditional failures.
      */
     virtual void setStCondFailures(unsigned int sc_failures) = 0;

     /**
      * Returns the number of consecutive store conditional failures.
      */
     virtual unsigned int readStCondFailures() const = 0;

     /** @} */

     /** Returns a pointer to the ThreadContext. */
     virtual ThreadContext *tcBase() const = 0;

     /**
      * @{
      * @name ARM-Specific Interfaces
      */

     virtual bool readPredicate() const = 0;
     virtual void setPredicate(bool val) = 0;
     virtual bool readMemAccPredicate() const = 0;
     virtual void setMemAccPredicate(bool val) = 0;

     // hardware transactional memory
     virtual uint64_t newHtmTransactionUid() const = 0;
     virtual uint64_t getHtmTransactionUid() const = 0;
     virtual bool inHtmTransactionalState() const = 0;
     virtual uint64_t getHtmTransactionalDepth() const = 0;

     /** @} */

     /**
      * @{
      * @name X86-Specific Interfaces
      */

     /**
      * Invalidate a page in the DTLB <i>and</i> ITLB.
      */
     virtual void demapPage(Addr vaddr, uint64_t asn) = 0;
     virtual void armMonitor(Addr address) = 0;
     virtual bool mwait(PacketPtr pkt) = 0;
     virtual void mwaitAtomic(ThreadContext *tc) = 0;
     virtual AddressMonitor *getAddrMonitor() = 0;

     /** @} */
 };

 } // namespace gem5

 #endif // __CPU_EXEC_CONTEXT_HH__
	/*
	* Copyright (c) 2014, 2016-2018, 2020-2021 ARM Limited
	* All rights reserved
	*
	* The license below extends only to copyright in the software and shall
	* not be construed as granting a license to any other intellectual
	* property including but not limited to intellectual property relating
	* to a hardware implementation of the functionality of the software
	* licensed hereunder. You may use the software subject to the license
	* terms below provided that you ensure that this notice is replicated
	* unmodified and in its entirety in all distributions of the software,
	* modified or unmodified, in source code or in binary form.
	*
	* Copyright (c) 2002-2005 The Regents of The University of Michigan
	* Copyright (c) 2015 Advanced Micro Devices, Inc.
	* 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.
	*/

	#ifndef __CPU_EXEC_CONTEXT_HH__
	#define __CPU_EXEC_CONTEXT_HH__

	#include "base/types.hh"
	#include "cpu/base.hh"
	#include "cpu/reg_class.hh"
	#include "cpu/static_inst_fwd.hh"
	#include "cpu/translation.hh"
	#include "mem/request.hh"

	namespace gem5
	{

	/**
	* The ExecContext is an abstract base class the provides the
	* interface used by the ISA to manipulate the state of the CPU model.
	*
	* Register accessor methods in this class typically provide the index
	* of the instruction's operand (e.g., 0 or 1), not the architectural
	* register index, to simplify the implementation of register
	* renaming. The architectural register index can be found by
	* indexing into the instruction's own operand index table.
	*
	* @note The methods in this class typically take a raw pointer to the
	* StaticInst is provided instead of a ref-counted StaticInstPtr to
	* reduce overhead as an argument. This is fine as long as the
	* implementation doesn't copy the pointer into any long-term storage
	* (which is pretty hard to imagine they would have reason to do).
	*/
	class ExecContext
	{
	public:

	virtual RegVal getRegOperand(const StaticInst *si, int idx) = 0;
	virtual void getRegOperand(const StaticInst si, int idx, void val) = 0;
	virtual void getWritableRegOperand(const StaticInst si, int idx) = 0;
	virtual void setRegOperand(const StaticInst *si, int idx, RegVal val) = 0;
	virtual void setRegOperand(const StaticInst *si, int idx,
	const void *val) = 0;

	/**
	* @{
	* @name Misc Register Interfaces
	*/
	virtual RegVal readMiscRegOperand(const StaticInst *si, int idx) = 0;
	virtual void setMiscRegOperand(const StaticInst *si,
	int idx, RegVal val) = 0;

	/**
	* Reads a miscellaneous register, handling any architectural
	* side effects due to reading that register.
	*/
	virtual RegVal readMiscReg(int misc_reg) = 0;

	/**
	* Sets a miscellaneous register, handling any architectural
	* side effects due to writing that register.
	*/
	virtual void setMiscReg(int misc_reg, RegVal val) = 0;

	/** @} */

	/**
	* @{
	* @name PC Control
	*/
	virtual const PCStateBase &pcState() const = 0;
	virtual void pcState(const PCStateBase &val) = 0;
	/** @} */

	/**
	* @{
	* @name Memory Interface
	*/
	/**
	* Perform an atomic memory read operation. Must be overridden
	* for exec contexts that support atomic memory mode. Not pure
	* virtual since exec contexts that only support timing memory
	* mode need not override (though in that case this function
	* should never be called).
	*/
	virtual Fault
	readMem(Addr addr, uint8_t *data, unsigned int size,
	Request::Flags flags, const std::vector<bool>& byte_enable)
	{
	panic("ExecContext::readMem() should be overridden\n");
	}

	/**
	* Initiate a timing memory read operation. Must be overridden
	* for exec contexts that support timing memory mode. Not pure
	* virtual since exec contexts that only support atomic memory
	* mode need not override (though in that case this function
	* should never be called).
	*/
	virtual Fault
	initiateMemRead(Addr addr, unsigned int size,
	Request::Flags flags, const std::vector<bool>& byte_enable)
	{
	panic("ExecContext::initiateMemRead() should be overridden\n");
	}

	/**
	* Initiate a memory management command with no valid address.
	* Currently, these instructions need to bypass squashing in the O3 model
	* Examples include HTM commands and TLBI commands.
	* e.g. tell Ruby we're starting/stopping a HTM transaction,
	* or tell Ruby to issue a TLBI operation
	*/
	virtual Fault initiateMemMgmtCmd(Request::Flags flags) = 0;

	/**
	* For atomic-mode contexts, perform an atomic memory write operation.
	* For timing-mode contexts, initiate a timing memory write operation.
	*/
	virtual Fault writeMem(uint8_t *data, unsigned int size, Addr addr,
	Request::Flags flags, uint64_t *res,
	const std::vector<bool>& byte_enable) = 0;

	/**
	* For atomic-mode contexts, perform an atomic AMO (a.k.a., Atomic
	* Read-Modify-Write Memory Operation)
	*/
	virtual Fault
	amoMem(Addr addr, uint8_t *data, unsigned int size,
	Request::Flags flags, AtomicOpFunctorPtr amo_op)
	{
	panic("ExecContext::amoMem() should be overridden\n");
	}

	/**
	* For timing-mode contexts, initiate an atomic AMO (atomic
	* read-modify-write memory operation)
	*/
	virtual Fault
	initiateMemAMO(Addr addr, unsigned int size, Request::Flags flags,
	AtomicOpFunctorPtr amo_op)
	{
	panic("ExecContext::initiateMemAMO() should be overridden\n");
	}

	/**
	* Sets the number of consecutive store conditional failures.
	*/
	virtual void setStCondFailures(unsigned int sc_failures) = 0;

	/**
	* Returns the number of consecutive store conditional failures.
	*/
	virtual unsigned int readStCondFailures() const = 0;

	/** @} */

	/** Returns a pointer to the ThreadContext. */
	virtual ThreadContext *tcBase() const = 0;

	/**
	* @{
	* @name ARM-Specific Interfaces
	*/

	virtual bool readPredicate() const = 0;
	virtual void setPredicate(bool val) = 0;
	virtual bool readMemAccPredicate() const = 0;
	virtual void setMemAccPredicate(bool val) = 0;

	// hardware transactional memory
	virtual uint64_t newHtmTransactionUid() const = 0;
	virtual uint64_t getHtmTransactionUid() const = 0;
	virtual bool inHtmTransactionalState() const = 0;
	virtual uint64_t getHtmTransactionalDepth() const = 0;

	/** @} */

	/**
	* @{
	* @name X86-Specific Interfaces
	*/

	/**
	* Invalidate a page in the DTLB <i>and</i> ITLB.
	*/
	virtual void demapPage(Addr vaddr, uint64_t asn) = 0;
	virtual void armMonitor(Addr address) = 0;
	virtual bool mwait(PacketPtr pkt) = 0;
	virtual void mwaitAtomic(ThreadContext *tc) = 0;
	virtual AddressMonitor *getAddrMonitor() = 0;

	/** @} */
	};

	} // namespace gem5

	#endif // __CPU_EXEC_CONTEXT_HH__