/*!
 \file A_extension.h
 \brief Implement A extensions part of the RISC-V
 \author Màrius Montón
 \date December 2018
 */
// SPDX-License-Identifier: GPL-3.0-or-later

#ifndef A_EXTENSION__H
#define A_EXTENSION__H

#include "systemc"

#include <unordered_set>

#include "Log.h"
#include "Registers.h"
#include "MemoryInterface.h"
#include "extension_base.h"

typedef enum {
	OP_A_LR,
	OP_A_SC,
	OP_A_AMOSWAP,
	OP_A_AMOADD,
	OP_A_AMOXOR,
	OP_A_AMOAND,
	OP_A_AMOOR,
	OP_A_AMOMIN,
	OP_A_AMOMAX,
	OP_A_AMOMINU,
	OP_A_AMOMAXU,

	OP_A_ERROR
} op_A_Codes;

typedef enum {
	A_LR = 0b00010,
	A_SC = 0b00011,
	A_AMOSWAP = 0b00001,
	A_AMOADD = 0b00000,
	A_AMOXOR = 0b00100,
	A_AMOAND = 0b01100,
	A_AMOOR = 0b01000,
	A_AMOMIN = 0b10000,
	A_AMOMAX = 0b10100,
	A_AMOMINU = 0b11000,
	A_AMOMAXU = 0b11100,
} A_Codes;

/**
 * @brief Instruction decoding and fields access
 */
class A_extension: public extension_base {
public:

	/**
	 * @brief Constructor, same as base class
	 */
	using extension_base::extension_base;

	/**
	 * @brief Access to opcode field
	 * @return return opcode field
	 */
	inline int32_t opcode() const override {
		return m_instr.range(31, 27);
	}

	/**
	 * @brief Access to rd field
	 * @return rd field
	 */
	inline int32_t get_rd() const override {
		return m_instr.range(11, 7);
	}

	inline void set_rd(int32_t value) override {
		m_instr.range(11, 7) = value;
	}

	/**
	 * @brief Access to rs1 field
	 * @return rs1 field
	 */
	inline int32_t get_rs1() const override {
		return m_instr.range(19, 15);
	}

	inline void set_rs1(int32_t value) override {
		m_instr.range(19, 15) = value;
	}

	/**
	 * @brief Access to rs2 field
	 * @return rs2 field
	 */
	inline int32_t get_rs2() const override {
		return m_instr.range(24, 20);
	}

	inline void set_rs2(int32_t value) override {
		m_instr.range(24, 20) = value;
	}

	inline int32_t get_funct3() const override {
		return m_instr.range(14, 12);
	}

	inline void set_funct3(int32_t value) override {
		m_instr.range(14, 12) = value;
	}

	/**
	 * @brief Decodes opcode of instruction
	 * @return opcode of instruction
	 */
	op_A_Codes decode() const;

	inline void dump() const override {
		std::cout << std::hex << "0x" << m_instr << std::dec << std::endl;
	}

	bool Exec_A_LR();
	bool Exec_A_SC();
	bool Exec_A_AMOSWAP() const;
	bool Exec_A_AMOADD() const;
	bool Exec_A_AMOXOR() const;
	bool Exec_A_AMOAND() const;
	bool Exec_A_AMOOR() const;
	bool Exec_A_AMOMIN() const;
	bool Exec_A_AMOMAX() const;
	bool Exec_A_AMOMINU() const;
	bool Exec_A_AMOMAXU() const;

	bool process_instruction(Instruction *inst);

	void TLB_reserve(uint32_t address);
	bool TLB_reserved(uint32_t address);

private:
	std::unordered_set<uint32_t> TLB_A_Entries;
};

#endif