/*
 * Copyright 2022 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors: AMD
 *
 */

#include "dml_frl_cap_chk.h"
#include "display_mode_util.h"
#include "lib_frl_cap_check.h"

#define frl_dump_var(fmt, var) {}
#define frl_print(fmt, ...) {}
#include "dcn_calc_math.h"
#define fabs(var) dcn_bw_fabs(var)
#define floor(var) dcn_bw_floor(var)
#define ceil(var) dcn_bw_ceil(var)

#if !defined(TB_BORROWED_MAX)
#define TB_BORROWED_MAX 400
#endif

static const double   EPSILON               = 0.01;
static const double   DBL_EPSILON           = 2.2204460492503131e-16;
static const int      C_FRL_CB              = 510;
static const double   OVERHEAD_M            = 0.003;  /* %   */
static const double   TOLERANCE_PIXEL_CLOCK = 0.005;  /* %   */
static const double   TOLERANCE_AUDIO_CLOCK = 1000;   /* ppm */
static const int      TOLERANCE_FRL_BIT     = 300;    /* ppm */
static const int      ACR_RATE_MAX          = 1500;

static frl_cap_chk_result frl_cap_chk_common(frl_cap_chk_intermediates *inter, frl_cap_chk_params *params)
{
        double   audio_bw_reserve = (params->compressed ? 192000.0 : 0.0);
/*
        if (getenv("DEBUG_FRL_CAP_CHK"))
        {
                printf("frl_cap_chk inputs:\n");
                printf("-------------------\n");
                frl_dump_var("%i", params->lanes);
                frl_dump_var("%le", params->f_pixel_clock_nominal);
                frl_dump_var("%le", params->r_bit_nominal);
                frl_dump_var("%i", params->audio_packet_type);
                frl_dump_var("%le", params->f_audio);
                frl_dump_var("%i", params->h_active);
                frl_dump_var("%i", params->h_blank);
                frl_dump_var("%i", params->bpc);
                frl_dump_var("%i", params->pixel_encoding);
                frl_dump_var("%i", params->compressed);
                frl_dump_var("%i", params->slices);
                frl_dump_var("%i", params->slice_width);
                frl_dump_var("%le", params->bpp_target);
                frl_dump_var("%i", params->layout);
                frl_dump_var("%i", params->acat);
                printf("frl_cap_chk outputs:\n");
                printf("---------------------\n");
        }
*/
        inter->c_frl_sb = 4 * C_FRL_CB + params->lanes;
        inter->overhead_sb = (double) params->lanes / inter->c_frl_sb;
        inter->overhead_rs = 8.0 * 4.0 / inter->c_frl_sb;
        inter->overhead_map = 2.5 / inter->c_frl_sb;
        inter->overhead_min = inter->overhead_sb + inter->overhead_rs + inter->overhead_map;
        inter->overhead_max = inter->overhead_min + OVERHEAD_M;
        inter->f_pixel_clock_max = params->f_pixel_clock_nominal * (1.0 + TOLERANCE_PIXEL_CLOCK);
        inter->t_line = (params->h_active + params->h_blank) / inter->f_pixel_clock_max;
        inter->r_bit_min = params->r_bit_nominal * (1.0 - TOLERANCE_FRL_BIT / 1000000.0);
        inter->r_frl_char_min = inter->r_bit_min / 18.0;
        inter->c_frl_line = floor(inter->t_line * inter->r_frl_char_min * params->lanes);
/*
        if (getenv("DEBUG_FRL_CAP_CHK"))
        {
                frl_dump_var("%i", inter->c_frl_sb);
                frl_dump_var("%le", inter->overhead_sb);
                frl_dump_var("%le", inter->overhead_rs);
                frl_dump_var("%le", inter->overhead_map);
                frl_dump_var("%le", inter->overhead_min);
                frl_dump_var("%le", inter->overhead_max);
                frl_dump_var("%le", inter->f_pixel_clock_max);
                frl_dump_var("%le", inter->t_line);
                frl_dump_var("%le", inter->r_bit_min);
                frl_dump_var("%le", inter->r_frl_char_min);
                frl_dump_var("%le", inter->c_frl_line);
        }
*/
        switch (params->audio_packet_type) {
        case 0x02:
                /* unsupported
        case 0x07:
                */
                if (params->layout == 0)
                        inter->ap = 0.25;
                else if (params->layout == 1)
                        inter->ap = 1.0;
                break;
        case 0x08:
                inter->ap = 0.25;
                break;
        case 0x09:
                /* unsupported
        case 0x0e:
        case 0x0f:
                */
                inter->ap = 1.0;
                break;
                /* unsupported
        case 0x0b:
        case 0x0c:
                if (acat == 0x01)
                        ap = 2.0;
                else if (acat == 0x02)
                        ap = 3.0;
                else if (acat == 0x03)
                        ap = 4.0;
                break;
                */
        case 0x07:
        case 0x0e:
        case 0x0f:
        case 0x0b:
        case 0x0c:
                // Unsupported audio format
                return FRL_CAP_CHK_ERROR_UNSUPPORTED_AUDIO;
        default:
                inter->ap = 0.0;
        }

        inter->r_ap                   = (dml_max(audio_bw_reserve, params->f_audio * inter->ap) + 2 * ACR_RATE_MAX) * (1 + TOLERANCE_AUDIO_CLOCK / 1000000.0);
        inter->avg_audio_packets_line = inter->r_ap * inter->t_line;
        inter->audio_packets_line     = (int)ceil(inter->avg_audio_packets_line);
        inter->blank_audio_min        = 32 + 32 * inter->audio_packets_line; // h_blank_audio_min or hc_blank_audio_min

        params->audio_packets_line = inter->audio_packets_line;
/*
        if (getenv("DEBUG_FRL_CAP_CHK"))
        {
                frl_dump_var("%le", inter->ap);
                frl_dump_var("%le", inter->r_ap);
                frl_dump_var("%le", inter->avg_audio_packets_line);
                frl_dump_var("%i", inter->audio_packets_line);
                frl_dump_var("%i", inter->blank_audio_min);
        }
*/
        return FRL_CAP_CHK_OK;
}


static frl_cap_chk_result frl_cap_chk_uncompressed(frl_cap_chk_params *params, frl_cap_chk_intermediates *inter)
{
        frl_cap_chk_result      res;

        int k_420;
        double k_cd;
        int c_frl_free;
        int c_frl_rc_margin;
        int c_frl_rc_savings;
        int bpp;
        double bytes_line;
        int tb_active;
        int tb_blank ;
        double f_tb_average;
        double t_active_ref;
        double t_blank_ref;
        double t_active_min;
        double t_blank_min;
        double t_borrowed;
        double tb_borrowed;
        int c_frl_actual_payload;
        double utilization;
        double margin;

        res = frl_cap_chk_common(inter, params);
        if (res != FRL_CAP_CHK_OK) {
                return res;
        }

        k_420 = params->pixel_encoding == PIXEL_ENCODING_420 ? 2 : 1;
        k_cd = params->pixel_encoding == PIXEL_ENCODING_422 ? 1.0 : params->bpc / 8.0;
        c_frl_free = (int)dml_max(params->h_blank * k_cd / k_420 - 32 * (1 + inter->audio_packets_line) - 7, 0);
        c_frl_rc_margin = 4;
        c_frl_rc_savings = (int)floor(dml_max(((7.0/8.0) * c_frl_free) - c_frl_rc_margin, 0.0));
        bpp = (int)(24 * k_cd / k_420);
        bytes_line = bpp * params->h_active / 8.0;
        tb_active = (int)ceil(bytes_line / 3);
        tb_blank = (int)ceil(params->h_blank * k_cd / k_420);
/*
        if (getenv("DEBUG_FRL_CAP_CHK"))
        {
                frl_dump_var("%i", k_420);
                frl_dump_var("%le", k_cd);
                frl_dump_var("%i", c_frl_free);
                frl_dump_var("%i", c_frl_rc_margin);
                frl_dump_var("%i", c_frl_rc_savings);
                frl_dump_var("%i", bpp);
                frl_dump_var("%le", bytes_line);
                frl_dump_var("%i", tb_active);
                frl_dump_var("%i", tb_blank);
        }
*/
        if (!(inter->blank_audio_min <= tb_blank)) {
                frl_dump_var("%i", inter->blank_audio_min);
                frl_dump_var("%i", tb_blank);
                return FRL_CAP_CHK_ERROR_AUDIO_BW;
        }

        f_tb_average = (inter->f_pixel_clock_max / (params->h_active + params->h_blank)) * (tb_active + tb_blank);
        t_active_ref = inter->t_line * ((double) params->h_active / (params->h_active + params->h_blank));
        t_blank_ref  = inter->t_line * ((double) params->h_blank / (params->h_active + params->h_blank));
        t_active_min = (3.0 / 2.0) * tb_active / (params->lanes * inter->r_frl_char_min * (1.0 - inter->overhead_max));
        t_blank_min  = tb_blank / (params->lanes * inter->r_frl_char_min * (1.0 - inter->overhead_max));
/*
        if (getenv("DEBUG_FRL_CAP_CHK"))
        {
                frl_dump_var("%le", f_tb_average);
                frl_dump_var("%le", t_active_ref);
                frl_dump_var("%le", t_blank_ref);
                frl_dump_var("%le", t_active_min);
                frl_dump_var("%le", t_blank_min);
        }
*/
        if ((t_active_ref >= t_active_min) && (t_blank_ref >= t_blank_min)) {
                t_borrowed = 0;
                params->borrow_mode = BORROW_MODE_NONE;
        } else if ((t_active_ref < t_active_min) && (t_blank_ref >= t_blank_min)) {
                t_borrowed = t_active_min - t_active_ref;
                params->borrow_mode = BORROW_MODE_FROM_BLANK;
        } else
                return FRL_CAP_CHK_ERROR_BORROW;

        tb_borrowed = ceil(t_borrowed * f_tb_average);
/*
        if (getenv("DEBUG_FRL_CAP_CHK"))
        {
                frl_dump_var("%le", tb_borrowed);
                frl_dump_var("%i", params->borrow_mode);
}
*/
        if (!(tb_borrowed <= TB_BORROWED_MAX))
                return FRL_CAP_CHK_ERROR_MAX_BORROW;

        c_frl_actual_payload = (int)ceil((3.0/2.0) * tb_active) + tb_blank - c_frl_rc_savings;
        utilization          = c_frl_actual_payload / inter->c_frl_line;
        margin               = 1.0 - (utilization + inter->overhead_max);
/*
        if (getenv("DEBUG_FRL_CAP_CHK"))
        {
                frl_dump_var("%i",  c_frl_actual_payload);
                frl_dump_var("%le", utilization);
                frl_dump_var("%le", margin);
        }
*/
        if (margin < 0 && fabs(margin) > EPSILON)
                return FRL_CAP_CHK_ERROR_MARGIN;

        return FRL_CAP_CHK_OK;
}



static frl_cap_chk_result frl_cap_chk_compressed(frl_cap_chk_params *params, frl_cap_chk_intermediates *inter)
{
        frl_cap_chk_result          res;

        int      c_frl_available;
        int      c_frl_active_available;
        int      c_frl_blank_available;
        int      bytes_target;
        int      hc_active_target;
        int      hc_blank_target_est1;
        int      hc_blank_target_est2;
        int      hc_blank_target;
        double   f_tb_average;
        double   t_active_ref;
        double   t_blank_ref;
        double   t_active_target;
        double   t_blank_target;
        double   tb_borrowed;
        int      c_frl_actual_target_payload;
        double   utilization_targeted;
        double   margin_target;

        res = frl_cap_chk_common(inter, params);
        if (res != FRL_CAP_CHK_OK)
                return res;

        c_frl_available        = (int)floor((1 - inter->overhead_max) * inter->c_frl_line);
        c_frl_active_available = (int)floor(c_frl_available * ((double) params->h_active / (params->h_active + params->h_blank)));
        (void) c_frl_active_available;
        c_frl_blank_available  = (int)floor(c_frl_available * ((double) params->h_blank / (params->h_active + params->h_blank)));
        (void) c_frl_blank_available;
        bytes_target           = params->slices * (int)ceil(params->bpp_target * params->slice_width / 8.0);

        if (!params->bypass_hc_target_calc)
                hc_active_target = (int)ceil(bytes_target / 3.0);
        else
                hc_active_target = params->hc_active_target;

        hc_blank_target_est1   = (int)ceil(hc_active_target * ((double) params->h_blank / params->h_active));
        hc_blank_target_est2   = (int)dml_max(hc_blank_target_est1, inter->blank_audio_min);

        if (!params->bypass_hc_target_calc) {
                hc_blank_target = 4 * (int)floor(dml_min(hc_blank_target_est2, c_frl_available - 3.0/2.0 * hc_active_target) / 4.0);

                params->hc_active_target = hc_active_target;
                params->hc_blank_target = hc_blank_target;
        } else {
                hc_blank_target  = params->hc_blank_target;
        }
/*
        if (getenv("DEBUG_FRL_CAP_CHK"))
        {
                frl_dump_var("%i", c_frl_available);
                frl_dump_var("%i", c_frl_active_available);
                frl_dump_var("%i", c_frl_blank_available);
                frl_dump_var("%i", bytes_target);
                frl_dump_var("%i", hc_active_target);
                frl_dump_var("%i", hc_blank_target_est1);
                frl_dump_var("%i", hc_blank_target_est2);
                frl_dump_var("%i", hc_blank_target);
        }
*/
        if (!(inter->blank_audio_min <= hc_blank_target)) {
                frl_dump_var("%i", inter->blank_audio_min);
                frl_dump_var("%i", hc_blank_target);
                return FRL_CAP_CHK_ERROR_AUDIO_BW;
        }

        f_tb_average    = inter->f_pixel_clock_max / (params->h_active + params->h_blank) * (hc_active_target + hc_blank_target);
        t_active_ref    = inter->t_line * ((double) params->h_active / (params->h_active + params->h_blank));
        t_blank_ref     = inter->t_line - t_active_ref; // * ((double) params->h_blank / (params->h_active + params->h_blank));
        t_active_target = dml_max((hc_active_target / f_tb_average), (3.0/2.0 * hc_active_target)/(params->lanes * inter->r_frl_char_min * (1.0 - inter->overhead_max)));
        t_blank_target  = inter->t_line - t_active_target;

        tb_borrowed     = t_active_target * f_tb_average - hc_active_target;
/*
        if (getenv("DEBUG_FRL_CAP_CHK"))
        {
                frl_dump_var("%le", f_tb_average);
                frl_dump_var("%le", t_active_ref);
                frl_dump_var("%le", t_blank_ref);
                frl_dump_var("%le", t_active_target);
                frl_dump_var("%le", t_blank_target);
                frl_dump_var("%le", tb_delta);
        }
*/
        if (t_blank_target - t_blank_ref > DBL_EPSILON) {
                params->borrow_mode = BORROW_MODE_FROM_ACTIVE;
        } else if (t_active_target - t_active_ref > DBL_EPSILON) {
                params->borrow_mode = BORROW_MODE_FROM_BLANK;
        } else {
                params->borrow_mode = BORROW_MODE_NONE;
        }

/*
        if (getenv("DEBUG_FRL_CAP_CHK"))
        {
                frl_dump_var("%le", tb_delta_limit);
                frl_dump_var("%le", tb_borrowed);
                frl_dump_var("%i", params->borrow_mode);
                frl_dump_var("%i", tb_worst);
        }
*/
        if (!(tb_borrowed <= TB_BORROWED_MAX))
                return FRL_CAP_CHK_ERROR_MAX_BORROW;

        c_frl_actual_target_payload = (int)ceil(3.0/2.0 * hc_active_target) + hc_blank_target;
        utilization_targeted        = c_frl_actual_target_payload / inter->c_frl_line;
        margin_target               = 1.0 - (utilization_targeted + inter->overhead_max);
/*
        if (getenv("DEBUG_FRL_CAP_CHK"))
        {
                frl_dump_var("%i", c_frl_actual_target_payload);
                frl_dump_var("%le", utilization_targeted);
                frl_dump_var("%le", margin_target);
        }
*/
        // oversubscribed bandwidth relative to margin
        if (margin_target < 0 && fabs(margin_target) > EPSILON)
                return FRL_CAP_CHK_ERROR_MARGIN;

        return FRL_CAP_CHK_OK;
}

frl_cap_chk_result frl_cap_chk(frl_cap_chk_params *params)
{
        frl_cap_chk_intermediates   inter;
        return frl_cap_chk_inter(params, &inter);
}

frl_cap_chk_result frl_cap_chk_inter(frl_cap_chk_params *params, frl_cap_chk_intermediates *inter)
{
        if (params->compressed)
                return frl_cap_chk_compressed(params, inter);
        return frl_cap_chk_uncompressed(params, inter);
}