/*********************************************************************
 *  The following code is part of the power modelling feature of VTR.
 *
 * For support:
 * http://code.google.com/p/vtr-verilog-to-routing/wiki/Power
 *
 * or email:
 * vtr.power.estimation@gmail.com
 *
 * If you are using power estimation for your researach please cite:
 *
 * Jeffrey Goeders and Steven Wilton.  VersaPower: Power Estimation
 * for Diverse FPGA Architectures.  In International Conference on
 * Field Programmable Technology, 2012.
 *
 ********************************************************************/

/**
 * This is the top-level file for power estimation in VTR
 */

#ifndef __POWER_H__
#define __POWER_H__

/************************* INCLUDES *********************************/
#include <list>

#include "vpr_types.h"
#include "PowerSpicedComponent.h"

/************************* DEFINES ***********************************/
/* Maximum size of logs */
#define MAX_LOGS 10000

/* Default clock behaviour */
#define CLOCK_PROB 0.5
#define CLOCK_DENS 2

/************************* ENUMS ************************************/

/* Return code used by power functions */
typedef enum {
    POWER_RET_CODE_SUCCESS = 0,
    POWER_RET_CODE_ERRORS,
    POWER_RET_CODE_WARNINGS
} e_power_ret_code;

/* Power log types */
typedef enum {
    POWER_LOG_ERROR,
    POWER_LOG_WARNING,
    POWER_LOG_NUM_TYPES
} e_power_log_type;

/* Multiplexer select encoding types */
#if 0
typedef enum {
	ENCODING_ONE_HOT, /* One SRAM bit per mux input */
	ENCODING_DECODER /* Log2(mux_inputs) SRAM bits */
}e_encoding_type;
#endif

/************************* STRUCTS **********************************/
struct t_power_output;
struct t_log;
struct t_power_commonly_used;
struct t_power_mux_volt_inf;
struct t_power_mux_volt_pair;
struct t_power_nmos_leakages;
struct t_power_nmos_leakage_pair;
struct t_power_buffer_sc_levr_inf;
struct t_power_tech;
struct t_transistor_inf;
struct t_transistor_size_inf;
struct t_rr_node_power;
struct t_power_buffer_size_inf;
struct t_power_buffer_strength_inf;
struct t_mux_node;
struct t_mux_arch;
struct t_solution_inf;
struct t_power_nmos_mux_inf;
struct t_power_nmos_leakage_inf;
struct t_power_mux_info;

/* Information on the solution obtained by VPR */
struct t_solution_inf {
    float T_crit;
    int channel_width;
};

/* two types of transisters */
enum e_tx_type {
    NMOS,
    PMOS
};

/* Information for a given transistor size */
struct t_transistor_size_inf {
    float size;

    /* Subthreshold leakage, for Vds = Vdd */
    float leakage_subthreshold;

    /* Gate leakage for Vgd/Vgs = Vdd */
    float leakage_gate;

    /* Gate, Source, Drain capacitance */
    float C_g;
    float C_s;
    float C_d;
};

/**
 * Transistor information
 */
struct t_transistor_inf {
    int num_size_entries;
    t_transistor_size_inf* size_inf;       /* Array of transistor sizes */
    t_transistor_size_inf* long_trans_inf; /* Long transistor (W=1,L=2) */
};

struct t_power_nmos_mux_inf {
    float nmos_size;
    int max_mux_sl_size;
    t_power_mux_volt_inf* mux_voltage_inf;
};

struct t_power_nmos_leakage_inf {
    float nmos_size;
    int num_leakage_pairs;
    t_power_nmos_leakage_pair* leakage_pairs;
};

/* CMOS technology properties, populated from data in xml file */
struct t_power_tech {
    float PN_ratio; /* Ratio of PMOS to NMOS in inverter */
    float Vdd;

    float tech_size;   /* Tech size in nm, for example 90e-9 for 90nm */
    float temperature; /* Temp in C */

    t_transistor_inf NMOS_inf;
    t_transistor_inf PMOS_inf;

    /* Pass Multiplexor Voltage Information */
    int num_nmos_mux_info;
    t_power_nmos_mux_inf* nmos_mux_info;

    /* NMOS Leakage by Vds */
    int num_nmos_leakage_info;
    t_power_nmos_leakage_inf* nmos_leakage_info;

    /* Buffer Info */
    int max_buffer_size;
    t_power_buffer_size_inf* buffer_size_inf;
};

/* Buffer information for a given size (# of stages) */
struct t_power_buffer_size_inf {
    int num_strengths;
    t_power_buffer_strength_inf* strength_inf;
};

/* Set of I/O Voltages for a single-level multiplexer */
struct t_power_mux_volt_inf {
    int num_voltage_pairs;
    t_power_mux_volt_pair* mux_voltage_pairs;
};

/* Single I/O voltage for a single-level multiplexer */
struct t_power_mux_volt_pair {
    float v_in;
    float v_out_min;
    float v_out_max;
};

/* Buffer information for a given buffer stength */
struct t_power_buffer_strength_inf {
    float stage_gain;

    /* Short circuit factor - no level restorer */
    float sc_no_levr;

    /* Short circuit factors - level restorers */
    int num_levr_entries;
    t_power_buffer_sc_levr_inf* sc_levr_inf;
};

/* Buffer short-circuit information for a given input mux size */
struct t_power_buffer_sc_levr_inf {
    int mux_size;

    /* Short circuit factor */
    float sc_levr;
};

/* Vds/Ids subthreshold leakage pair */
struct t_power_nmos_leakage_pair {
    float v_ds;
    float i_ds;
};

/* Output details of the power estimation */
struct t_power_output {
    FILE* out;
    t_log* logs;
    int num_logs;
};

struct t_log {
    char* name;
    char** messages;
    int num_messages;
};

struct t_power_mux_info {
    /* Mux architecture information for 0..mux_arch_max_size */
    int mux_arch_max_size;
    t_mux_arch* mux_arch;
};

/**
 * Commonly used values that are cached here instead of recalculting each time,
 * also includes statistics.
 */
struct t_power_commonly_used {
    /* Capacitances */
    float NMOS_1X_C_g;
    float NMOS_1X_C_d;
    float NMOS_1X_C_s;

    float PMOS_1X_C_g;
    float PMOS_1X_C_d;
    float PMOS_1X_C_s;

    float INV_1X_C_in;
    float INV_1X_C;
    float INV_2X_C;

    /* Component Callibrations Array [0..POWER_COMPONENT_MAX_NUM-1] */
    PowerSpicedComponent** component_callibration;

    /* Subthreshold leakages */
    float NMOS_1X_st_leakage;
    float NMOS_2X_st_leakage;
    float PMOS_1X_st_leakage;
    float PMOS_2X_st_leakage;

    std::map<float, t_power_mux_info*> mux_info;

    /* Routing stats */
    int max_routing_mux_size;
    int max_IPIN_fanin;
    int max_seg_fanout;
    int max_seg_to_IPIN_fanout;
    int max_seg_to_seg_fanout;

    /* Physical length of a tile (meters) */
    float tile_length;

    /* Size of switch and connection box buffers */
    int num_sb_buffers;
    float total_sb_buffer_size;

    int num_cb_buffers;
    float total_cb_buffer_size;
};

/* 1-to-1 data structure with t_rr_node
 */
struct t_rr_node_power {
    float* in_dens;             /* Switching density of inputs */
    float* in_prob;             /* Static probability of inputs */
    ClusterNetId net_num;       /* Net number using the associated rr_node */
    t_edge_size num_inputs;     /* Number of inputs */
    t_edge_size selected_input; /* Input index that is selected */
    short driver_switch_type;   /* Switch type that drives this resource */
    bool visited;               /* When traversing netlist, need to track whether the node has been processed */
};

/* Architecture information for a multiplexer.
 * This is used to specify transistor sizes, encoding, etc.
 */
struct t_mux_arch {
    int levels;
    int num_inputs;
    float transistor_size;
    //enum e_encoding_type * encoding_types;
    t_mux_node* mux_graph_head;
};

/* A single-level multiplexer data structure.
 * These are combined in a hierarchy to represent
 * multi-level multiplexers
 */
struct t_mux_node {
    int num_inputs;       /* Number of inputs */
    t_mux_node* children; /* Multiplexers that drive the inputs [0..num_inputs-1] */
    int starting_pin_idx; /* Applicable to level 0 only, the overall mux primary input index */
    int level;            /* Level in the full multilevel mux - 0 = primary inputs to mux */
    bool level_restorer;  /* Whether the output of this mux is level restored */
};

/************************* FUNCTION DECLARATIONS ********************/

/* Call before using power module */
bool power_init(const char* power_out_filepath,
                const char* cmos_tech_behavior_filepath,
                const t_arch* arch,
                const t_det_routing_arch* routing_arch);

bool power_uninit();

/* Top-Level Function */
e_power_ret_code power_total(float* run_time_s, const t_vpr_setup& vpr_setup, const t_arch* arch, const t_det_routing_arch* routing_arch);

#endif /* __POWER_H__ */