metroboy

#include "GateBoySPU.h"

#include "GateBoy.h"

#ifdef SIM_AUDIO

#define DELTA_AB ((phase_new & 7) == 1)
#define DELTA_BC ((phase_new & 7) == 2)
#define DELTA_CD ((phase_new & 7) == 3)
#define DELTA_DE ((phase_new & 7) == 4)
#define DELTA_EF ((phase_new & 7) == 5)
#define DELTA_FG ((phase_new & 7) == 6)
#define DELTA_GH ((phase_new & 7) == 7)
#define DELTA_HA ((phase_new & 7) == 0)

sample_t ch4_audio_out_fast(const SpuChannel4& ch4) {

  ///*_p09.EDEK*/ wire EDEK_NR52_DBG_APUp = not1(reg_new.spu.FERO_NR52_DBG_APUp.qn_any());
  ///*_p20.DYRY*/ wire DYRY_DBG = and2(ch4.CUNY_NR44_LEN_ENp.qp_old(), EDEK_NR52_DBG_APUp);
  /*_p20.DYRY*/ wire DYRY_DBG = 0;

  /*_p20.GAME*/ wire GAME_LFSR_OUT = and2(ch4.GENA_CH4_ACTIVEp.qp_any(), ch4.HEZU_LFSR_15.qp_any());

  // ignoring debug thing on the audio out here
  wire FEME_LFSR_CLKp_new = 0;

  /*_p20.EZUL*/ wire EZUL_CH4_BIT_MUX = mux2p(DYRY_DBG, FEME_LFSR_CLKp_new, GAME_LFSR_OUT);

  ///*_p20.CEPY*/ wire CEPY_NR44_STOPn = not1(ch4.CUNY_NR44_LEN_ENp.qp_old());
  ///*_p20.COTE*/ wire COTE_DBG_CH4_MUTE = and2(CEPY_NR44_STOPn, EDEK_NR52_DBG_APUp);
  /*_p20.COTE*/ wire COTE_DBG_CH4_MUTE = 0;
  /*_p20.DATO*/ wire DATO_CH4_RAW_BIT = or2(EZUL_CH4_BIT_MUX, COTE_DBG_CH4_MUTE);

  /*#p20.AKOF*/ wire AKOF_CH4_DAC0 = and2(ch4.FEKO_CH4_VOL0.qp_any(), DATO_CH4_RAW_BIT);
  /*#p20.BYZY*/ wire BYZY_CH4_DAC1 = and2(ch4.FATY_CH4_VOL1.qp_any(), DATO_CH4_RAW_BIT);
  /*#p20.APYR*/ wire APYR_CH4_DAC2 = and2(ch4.FERU_CH4_VOL2.qp_any(), DATO_CH4_RAW_BIT);
  /*#p20.BOZA*/ wire BOZA_CH4_DAC3 = and2(ch4.FYRO_CH4_VOL3.qp_any(), DATO_CH4_RAW_BIT);

  return ((AKOF_CH4_DAC0 & 1) << 0) |
    ((BYZY_CH4_DAC1 & 1) << 1) |
    ((APYR_CH4_DAC2 & 1) << 2) |
    ((BOZA_CH4_DAC3 & 1) << 3);
}

//------------------------------------------------------------------------------

#pragma optimize("", off)
void tick_ch4_fast(
  uint64_t phase_new,
  int64_t spu_phase_new,

  const GateBoyCpuDBus& cpu_dbus_old,
  const GateBoySPU& spu_old,
  const SpuChannel4& ch4_old,
  const GateBoyWaveBus& wave_dbus_old,
  const GateBoyCpuABus& cpu_abus_new,

  GateBoyCpuDBus& cpu_dbus_new,
  GateBoySPU& spu_new,
  SpuChannel4& ch4_new,
  GateBoyWaveBus& wave_dbus_new,

  wire AFER_SYS_RSTp,
  wire ASOL_POR_DONEn,
  wire SIG_CPU_CLKREQ,
  wire AVET_AxCxExGx,
  wire AFUR_ABCDxxxx_qn,
  wire APUK_xxCDEFxx_qn,
  wire ALEF_xBCDExxx,
  wire SIG_IN_CPU_RDp,
  wire SIG_IN_CPU_WRp,
  wire TEDO_CPU_RDp,
  wire TAPU_CPU_WRp,
  wire SIG_IN_CPU_DBUS_FREE,

  uint8_t* wave_ram
)
{
  auto addr = bit_pack(cpu_abus_new);
  auto dbus_old = bit_pack(cpu_dbus_old);
  auto dbus_new = bit_pack(cpu_dbus_new);
  bool apu_rst = bit(or3(AFER_SYS_RSTp, ASOL_POR_DONEn, spu_new.HADA_NR52_ALL_SOUND_ON.qn_any()));

  /*#p01.BUDE*/ wire BUDE_xxxxEFGH = and2(AFUR_ABCDxxxx_qn, SIG_CPU_CLKREQ);
  /*_p01.DOVA*/ wire DOVA_ABCDxxxx = not1(BUDE_xxxxEFGH);


  //wire HAMA_CLK_512K_old = not1(spu_old.JESO_CLK_512K.qp_any());
  wire HAMA_CLK_512K_new = not1(spu_new.JESO_CLK_512K.qp_any());

  wire BUFY_CLK_256_old = not1(spu_old.CARU_CLK_256.qp_any());
  //wire BYFE_CLK_128_old = not1(spu_old.BYLU_CLK_128.qp_any());

  wire HORU_CLK_512_new = spu_new.BARA_CLK_512.qp_any();
  wire BUFY_CLK_256_new = not1(spu_new.CARU_CLK_256.qp_any());
  wire BYFE_CLK_128_new = not1(spu_new.BYLU_CLK_128.qp_any());

  /*#p20.ABEL*/ ch4_new.ABEL_CLK_64.dff17(not1(BYFE_CLK_128_new), !apu_rst, ch4_old.ABEL_CLK_64.qn_any());

  auto clk64_old = bit(ch4_old.ABEL_CLK_64.state);
  auto clk64_new = bit(ch4_new.ABEL_CLK_64.state);


  auto nr42 = bit_pack(&ch4_new.EMOK_NR42_ENV_DELAY0p, 8);
  auto nr43 = bit_pack(&ch4_new.JARE_NR43_DIV0p, 8);

  if (apu_rst) {
    nr42 = 0;
    nr43 = 0;
    ch4_new.GYSU_CH4_TRIG.dff17(DOVA_ABCDxxxx, 0, ch4_old.HOGA_NR44_TRIGp.qp_any());
    ch4_new.GONE_CH4_TRIGp.dff17_clk(HAMA_CLK_512K_new, ch4_old.HAZO_CH4_TRIGn.qn_any());
    ch4_new.GORA_CH4_TRIGp.dff17(HAMA_CLK_512K_new, 0, ch4_old.GONE_CH4_TRIGp.qp_any());
    ch4_new.GATY_CH4_TRIGp.dff17(HAMA_CLK_512K_new, 0, ch4_old.GORA_CH4_TRIGp.qp_any());
    ch4_new.GONE_CH4_TRIGp.dff17_rst(0);
    ch4_new.HAZO_CH4_TRIGn.state = 1;
    ch4_new.CUNY_NR44_LEN_ENp.state = 0;
    ch4_new.HOGA_NR44_TRIGp.state = 0;
  }
  else {
    ch4_new.GYSU_CH4_TRIG.dff17(DOVA_ABCDxxxx, 1, ch4_old.HOGA_NR44_TRIGp.qp_any());
    ch4_new.GONE_CH4_TRIGp.dff17_clk(HAMA_CLK_512K_new, ch4_old.HAZO_CH4_TRIGn.qn_any());
    ch4_new.GORA_CH4_TRIGp.dff17(HAMA_CLK_512K_new, 1, ch4_old.GONE_CH4_TRIGp.qp_any());
    ch4_new.GATY_CH4_TRIGp.dff17(HAMA_CLK_512K_new, 1, ch4_old.GORA_CH4_TRIGp.qp_any());
    ch4_new.GONE_CH4_TRIGp.dff17_rst(~ch4_new.GORA_CH4_TRIGp.qp_any());
    ch4_new.HAZO_CH4_TRIGn.nor_latch(ch4_new.GORA_CH4_TRIGp.qp_any(), ch4_new.GYSU_CH4_TRIG.qp_any());

    if (DELTA_GH && SIG_IN_CPU_WRp && SIG_IN_CPU_DBUS_FREE) {
      if (addr == 0xFF21) nr42 = dbus_old;
      if (addr == 0xFF22) nr43 = dbus_old;
      if (addr == 0xFF23) {
        ch4_new.CUNY_NR44_LEN_ENp.state = cpu_dbus_old.BUS_CPU_D06p.qp_any();
        ch4_new.HOGA_NR44_TRIGp.state = cpu_dbus_old.BUS_CPU_D07p.qp_any();
      }
    }
  }

  if (bit(ch4_new.GYSU_CH4_TRIG.qp_any())) {
    ch4_new.HOGA_NR44_TRIGp.state = 0;
  }

  bit_unpack(&ch4_new.EMOK_NR42_ENV_DELAY0p, 8, nr42);
  bit_unpack(&ch4_new.JARE_NR43_DIV0p,       8, nr43);

  auto freq_delay_old = bit_pack(&ch4_old.JYCO_FREQ_DELAY0, 3);

  if (DELTA_AB) {
    ch4_new.GARY_FREQ_GATEp.state = freq_delay_old == 7;
  }

  if (!bit(nor2(apu_rst, ch4_new.GONE_CH4_TRIGp.qp_any()))) {
    ch4_new.GARY_FREQ_GATEp.state = 0;
  }

  auto freq_old = bit_pack(&ch4_old.CEXO_FREQ_00, 14);
  auto freq_new = bit_pack(&ch4_new.CEXO_FREQ_00, 14);

  if (DELTA_EF && bit(ch4_new.GARY_FREQ_GATEp.qp_any())) {
    freq_new++;
  }

  if (apu_rst) {
    freq_new = 0;
  }

  bit_unpack(&ch4_new.CEXO_FREQ_00, 14, freq_new);

  auto freq_mux_old = bit_pack(&ch4_old.FETA_NR43_FREQ0p, 4);
  auto freq_mux_new = bit_pack(&ch4_new.FETA_NR43_FREQ0p, 4);

  auto lfsr_clk_old = bit(freq_old, freq_mux_old);
  auto lfsr_clk_new = bit(freq_new, freq_mux_new);












  auto len_old = bit_pack(&ch4_new.DANO_NR41_LEN0p, 6);
  auto len_new = len_old;

  // fugo old cycle break
  wire CUWA_LEN_CLKa_old = or3(ch4_old.FUGO_CH4_LEN_DONEp.qp_any(), BUFY_CLK_256_old, ch4_old.CUNY_NR44_LEN_ENp.qn_any());
  wire CUWA_LEN_CLKa_new = or3(ch4_old.FUGO_CH4_LEN_DONEp.qp_any(), BUFY_CLK_256_new, ch4_new.CUNY_NR44_LEN_ENp.qn_any());

  if (negedge(CUWA_LEN_CLKa_old, CUWA_LEN_CLKa_new)) {
    len_new = (len_new + 1) % 64;
  }

  if (bit(and2(TAPU_CPU_WRp, addr == 0xFF20))) {
    len_new = dbus_new & 63;
  }

  wire GAPY_LEN_DONE_RSTn = nor3(and2(TAPU_CPU_WRp, addr == 0xFF20), apu_rst, ch4_new.GONE_CH4_TRIGp.qp_any());
  ch4_new.FUGO_CH4_LEN_DONEp.dff17(~bit(len_new, 5), GAPY_LEN_DONE_RSTn, ch4_old.FUGO_CH4_LEN_DONEp.qn_any());

  wire CUWA_LEN_CLKa2_new = or3(ch4_new.FUGO_CH4_LEN_DONEp.qp_any(), BUFY_CLK_256_new, ch4_new.CUNY_NR44_LEN_ENp.qn_any());

  auto len_new_bak = len_new;

  if (negedge(CUWA_LEN_CLKa_new, CUWA_LEN_CLKa2_new)) {
    len_new = (len_new + 1) % 64;
  }

  if (bit(and2(TAPU_CPU_WRp, addr == 0xFF20))) {
    len_new = dbus_new & 63;
  }

  if (len_new_bak != len_new) {
    //printf("?");
  }


  bit_unpack(&ch4_new.DANO_NR41_LEN0p, 6, len_new);








  wire GEVY_CH4_AMP_ENn = nor5(
    ch4_new.GEKY_NR42_ENV_DIRp.qp_any(),
    ch4_new.GARU_NR42_VOL0p.qp_any(),
    ch4_new.GOKY_NR42_VOL1p.qp_any(),
    ch4_new.GOZO_NR42_VOL2p.qp_any(),
    ch4_new.GEDU_NR42_VOL3p.qp_any());


  {

    if (bit(ch4_new.GONE_CH4_TRIGp.qp_any())) {
      ch4_new.GENA_CH4_ACTIVEp.state = 1;
    }

    wire EFOT_CH4_STOPp = and2(ch4_new.CUNY_NR44_LEN_ENp.qp_any(), ch4_new.FUGO_CH4_LEN_DONEp.qp_any());
    if (bit(or3(apu_rst, EFOT_CH4_STOPp, GEVY_CH4_AMP_ENn))) {
      ch4_new.GENA_CH4_ACTIVEp.state = 0;
    }
  }

  {
    /*#p20.JERY*/ ch4_new.JERY_FREQ_GATE.nand_latch(nor2(GEVY_CH4_AMP_ENn, apu_rst), not1(ch4_new.GATY_CH4_TRIGp.qp_any()));
  }

  {
    /*#p20.KANU*/ wire KANU_DIV_CLKa = or2(ch4_new.JERY_FREQ_GATE.qp_any(), spu_new.JESO_CLK_512K.qp_any());
    /*#p20.HUCE*/ wire HUCE_DIV_LOADp = or2(ch4_new.GONE_CH4_TRIGp.qp_any(), ch4_new.GARY_FREQ_GATEp.qp_any());

    /*#p20.JYCO*/ ch4_new.JYCO_FREQ_DELAY0.dff20(KANU_DIV_CLKa,                     HUCE_DIV_LOADp, ch4_new.JARE_NR43_DIV0p.qn_any());
    /*#p20.JYRE*/ ch4_new.JYRE_FREQ_DELAY1.dff20(ch4_new.JYCO_FREQ_DELAY0.qp_any(), HUCE_DIV_LOADp, ch4_new.JERO_NR43_DIV1p.qn_any());
    /*_p20.JYFU*/ ch4_new.JYFU_FREQ_DELAY2.dff20(ch4_new.JYRE_FREQ_DELAY1.qp_any(), HUCE_DIV_LOADp, ch4_new.JAKY_NR43_DIV2p.qn_any());
  }


  //----------
  // The actual LFSR

  auto lfsr = bit_pack(&ch4_new.JOTO_LFSR_00, 16);

  if (or2(ch4_new.GONE_CH4_TRIGp.qp_any(), apu_rst) & 1) {
    bit_unpack(&ch4_new.JOTO_LFSR_00, 16, 0);
  } else if (negedge(lfsr_clk_old, lfsr_clk_new)) {
    ch4_new.JOTO_LFSR_00.state = xnor2(ch4_old.HEZU_LFSR_15.qp_any(), ch4_old.HYRO_LFSR_14.qp_any());
  } else if (posedge(lfsr_clk_old, lfsr_clk_new)) {
    if (bit(ch4_old.JAMY_NR43_MODEp.qp_any())) lfsr = (lfsr & ~0x100) | (bit(lfsr, 0) << 8);
    bit_unpack(&ch4_new.KOMU_LFSR_01, 15, lfsr);
  }

  //----------
  // Env

  auto env_timer_old = bit_pack(&ch4_old.CUNA_ENV_TIMER0n, 3) ^ 7;
  //auto env_delay_old = bit_pack(&ch4_old.EMOK_NR42_ENV_DELAY0p, 3);
  auto env_delay_new = bit_pack(&ch4_new.EMOK_NR42_ENV_DELAY0p, 3);

  ch4_new.FOSY_ENV_CLKp.dff17_clk(HORU_CLK_512_new, env_timer_old != 7);

  if (bit(and2(~HORU_CLK_512_new, ch4_new.FOSY_ENV_CLKp.qp_any())) || (env_delay_new == 0) || bit(ch4_new.GONE_CH4_TRIGp.qp_any()) || apu_rst) {
    ch4_new.FOSY_ENV_CLKp.state &= ~1;
  }

  {
    if (negedge(clk64_old, clk64_new)) {
      auto timer = bit_pack(&ch4_new.CUNA_ENV_TIMER0n, 3);
      timer++;
      bit_unpack(&ch4_new.CUNA_ENV_TIMER0n, 3, timer);
    }

    if (bit(or2(ch4_new.GONE_CH4_TRIGp.qp_any(), ch4_new.FOSY_ENV_CLKp.qp_any()))) {
      auto delay = bit_pack(&ch4_new.EMOK_NR42_ENV_DELAY0p, 3);
      bit_unpack(&ch4_new.CUNA_ENV_TIMER0n, 3, ~delay);
    }
  }


  {
    auto vol_old = bit_pack(&ch4_old.FEKO_CH4_VOL0, 4);

    if (bit(ch4_old.GEKY_NR42_ENV_DIRp.qp_any())) {
      ch4_new.FYNO_VOL_MAXp.dff17(ch4_new.FOSY_ENV_CLKp.qp_any(), 1, vol_old == 15);
    } else {
      ch4_new.FYNO_VOL_MAXp.dff17(ch4_new.FOSY_ENV_CLKp.qp_any(), 1, vol_old == 0);
    }


    if (bit(or2(ch4_new.GONE_CH4_TRIGp.qp_any(), apu_rst))) {
      ch4_new.FYNO_VOL_MAXp.state &= ~1;
    }
  }


  if (bit(ch4_new.FYNO_VOL_MAXp.qp_any())) {
    ch4_new.EROX_ENV_RUNNINGn.state = 1;
  }
  if (bit(or2(apu_rst, ch4_new.GONE_CH4_TRIGp.qp_any()))) {
    ch4_new.EROX_ENV_RUNNINGn.state = 0;
  }


  ///*#p20.FELO*/ wire FELO_ENV_CLK_old = bit(or3(ch4_old.FOSY_ENV_CLKp.qp_any(), env_delay_old == 0, ch4_old.EROX_ENV_RUNNINGn.qp_any()));
  /*#p20.FELO*/ wire FELO_ENV_CLK_new = bit(or3(ch4_new.FOSY_ENV_CLKp.qp_any(), env_delay_new == 0, ch4_new.EROX_ENV_RUNNINGn.qp_any()));

  // If GEKY_NR42_ENV_DIRp changes while the env clock is running, the volume can end up in a weird state...

  // This is a race condition - GEKY and FELO change at the same time, and the resulting state is indeterminate.

  if (bit(ch4_new.GEKY_NR42_ENV_DIRp.qp_any())) {
    /*#p20.FEKO*/ ch4_new.FEKO_CH4_VOL0.dff20(FELO_ENV_CLK_new,               ch4_new.GONE_CH4_TRIGp.qp_any(), ch4_new.GARU_NR42_VOL0p.qp_any());
    /*#p20.FATY*/ ch4_new.FATY_CH4_VOL1.dff20(ch4_new.FEKO_CH4_VOL0.qp_any(), ch4_new.GONE_CH4_TRIGp.qp_any(), ch4_new.GOKY_NR42_VOL1p.qp_any());
    /*#p20.FERU*/ ch4_new.FERU_CH4_VOL2.dff20(ch4_new.FATY_CH4_VOL1.qp_any(), ch4_new.GONE_CH4_TRIGp.qp_any(), ch4_new.GOZO_NR42_VOL2p.qp_any());
    /*#p20.FYRO*/ ch4_new.FYRO_CH4_VOL3.dff20(ch4_new.FERU_CH4_VOL2.qp_any(), ch4_new.GONE_CH4_TRIGp.qp_any(), ch4_new.GEDU_NR42_VOL3p.qp_any());

  }
  else {
    /*#p20.FEKO*/ ch4_new.FEKO_CH4_VOL0.dff20(FELO_ENV_CLK_new,               ch4_new.GONE_CH4_TRIGp.qp_any(), ch4_new.GARU_NR42_VOL0p.qp_any());
    /*#p20.FATY*/ ch4_new.FATY_CH4_VOL1.dff20(ch4_new.FEKO_CH4_VOL0.qn_any(), ch4_new.GONE_CH4_TRIGp.qp_any(), ch4_new.GOKY_NR42_VOL1p.qp_any());
    /*#p20.FERU*/ ch4_new.FERU_CH4_VOL2.dff20(ch4_new.FATY_CH4_VOL1.qn_any(), ch4_new.GONE_CH4_TRIGp.qp_any(), ch4_new.GOZO_NR42_VOL2p.qp_any());
    /*#p20.FYRO*/ ch4_new.FYRO_CH4_VOL3.dff20(ch4_new.FERU_CH4_VOL2.qn_any(), ch4_new.GONE_CH4_TRIGp.qp_any(), ch4_new.GEDU_NR42_VOL3p.qp_any());
  }

  if (SIG_IN_CPU_RDp) {
    if (addr == 0xFF21) bit_unpack(cpu_dbus_new, bit_pack(&ch4_new.EMOK_NR42_ENV_DELAY0p, 8));
    if (addr == 0xFF22) bit_unpack(cpu_dbus_new, bit_pack(&ch4_new.JARE_NR43_DIV0p, 8));
    if (addr == 0xFF23) cpu_dbus_new.BUS_CPU_D06p.state = ch4_new.CUNY_NR44_LEN_ENp.qp_any();
  }
}

#endif