/* ----------------------------------------------------------------------

   LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator

   http://lammps.sandia.gov, Sandia National Laboratories

   Steve Plimpton, sjplimp@sandia.gov

   Copyright (2003) Sandia Corporation.  Under the terms of Contract

   DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains

   certain rights in this software.  This software is distributed under 

   the GNU General Public License.

   See the README file in the top-level LAMMPS directory.

------------------------------------------------------------------------- */

/* ----------------------------------------------------------------------

   Contributing authors: Mike Brown (ORNL), brownw@ornl.gov

------------------------------------------------------------------------- */

#include <iostream>

#include <cassert>

#include <math.h>

#include "crml_gpu_memory.h"

using namespace std;

static CRML_GPU_Memory<PRECISION,ACC_PRECISION> CRMLMF;

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

// Allocate memory on host and device and copy constants to device

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

bool crml_gpu_init(const int ntypes, double cut_bothsq, double **host_lj1,

                   double **host_lj2, double **host_lj3, double **host_lj4,

                   double **offset, double *special_lj, const int inum,

                   const int nall, const int max_nbors, const int maxspecial,

                   const double cell_size, int &gpu_mode, FILE *screen,

                   double host_cut_ljsq, double host_cut_coulsq,

                   double *host_special_coul, const double qqrd2e,

                   const double g_ewald, const double cut_lj_innersq,

                   const double denom_lj, double **epsilon,

                   double **sigma, const bool mix_arithmetic) {

  CRMLMF.clear();

  gpu_mode=CRMLMF.device->gpu_mode();

  double gpu_split=CRMLMF.device->particle_split();

  int first_gpu=CRMLMF.device->first_device();

  int last_gpu=CRMLMF.device->last_device();

  int world_me=CRMLMF.device->world_me();

  int gpu_rank=CRMLMF.device->gpu_rank();

  int procs_per_gpu=CRMLMF.device->procs_per_gpu();

  CRMLMF.device->init_message(screen,"lj/charmm/coul/long",first_gpu,last_gpu);

  bool message=false;

  if (CRMLMF.device->replica_me()==0 && screen)

    message=true;

  if (message) {

    fprintf(screen,"Initializing GPU and compiling on process 0...");

    fflush(screen);

  }

  if (world_me==0) {

    bool init_ok=CRMLMF.init(ntypes, cut_bothsq, host_lj1, host_lj2, host_lj3,

                             host_lj4, offset, special_lj, inum, nall, 300,

                             maxspecial, cell_size, gpu_split, screen,

                             host_cut_ljsq, host_cut_coulsq, host_special_coul,

                             qqrd2e, g_ewald, cut_lj_innersq, denom_lj,

                             epsilon,sigma,mix_arithmetic);

    if (!init_ok)

      return false;

  }

  CRMLMF.device->world_barrier();

  if (message)

    fprintf(screen,"Done.\n");

  for (int i=0; i<procs_per_gpu; i++) {

    if (message) {

      if (last_gpu-first_gpu==0)

        fprintf(screen,"Initializing GPU %d on core %d...",first_gpu,i);

      else

        fprintf(screen,"Initializing GPUs %d-%d on core %d...",first_gpu,

                last_gpu,i);

      fflush(screen);

    }

    if (gpu_rank==i && world_me!=0) {

      bool init_ok=CRMLMF.init(ntypes, cut_bothsq, host_lj1, host_lj2, host_lj3,

                               host_lj4, offset, special_lj, inum, nall, 300,

                               maxspecial, cell_size, gpu_split,

                               screen, host_cut_ljsq, host_cut_coulsq,

                               host_special_coul, qqrd2e, g_ewald, 

                               cut_lj_innersq, denom_lj, epsilon, sigma,

                               mix_arithmetic);

      if (!init_ok)

        return false;

    }

    CRMLMF.device->gpu_barrier();

    if (message) 

      fprintf(screen,"Done.\n");

  }

  if (message)

    fprintf(screen,"\n");

  return true;

}

void crml_gpu_clear() {

  CRMLMF.clear();

}

int * crml_gpu_compute_n(const int timestep, const int ago, const int inum_full,

                         const int nall, double **host_x, int *host_type,

                         double *boxlo, double *boxhi, int *tag, int **nspecial, 

                         int **special, const bool eflag, const bool vflag,

                         const bool eatom, const bool vatom, int &host_start,

                         const double cpu_time, bool &success, double *host_q) {

  return CRMLMF.compute(timestep, ago, inum_full, nall, host_x, host_type, boxlo,

                        boxhi, tag, nspecial, special, eflag, vflag, eatom,

                        vatom, host_start, cpu_time, success, host_q);

}  

void crml_gpu_compute(const int timestep, const int ago, const int inum_full,

	 	     const int nall, double **host_x, int *host_type,

                     int *ilist, int *numj, int **firstneigh,

		     const bool eflag, const bool vflag, const bool eatom,

                     const bool vatom, int &host_start, const double cpu_time,

                     bool &success, double *host_q) {

  CRMLMF.compute(timestep,ago,inum_full,nall,host_x,host_type,ilist,numj,

                firstneigh,eflag,vflag,eatom,vatom,host_start,cpu_time,success,

                host_q);

}

double crml_gpu_bytes() {

  return CRMLMF.host_memory_usage();

}

/* ----------------------------------------------------------------------

   LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator

   http://lammps.sandia.gov, Sandia National Laboratories

   Steve Plimpton, sjplimp@sandia.gov

   Copyright (2003) Sandia Corporation.  Under the terms of Contract

   DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains

   certain rights in this software.  This software is distributed under 

   the GNU General Public License.

   See the README file in the top-level LAMMPS directory.

------------------------------------------------------------------------- */

/* ----------------------------------------------------------------------

   Contributing authors: Mike Brown (ORNL), brownw@ornl.gov

------------------------------------------------------------------------- */

#ifdef USE_OPENCL

#include "crml_gpu_cl.h"

#else

#include "crml_gpu_ptx.h"

#endif

#include "crml_gpu_memory.h"

#include <cassert>

#define CRML_GPU_MemoryT CRML_GPU_Memory<numtyp, acctyp>

extern PairGPUDevice<PRECISION,ACC_PRECISION> pair_gpu_device;

template <class numtyp, class acctyp>

CRML_GPU_MemoryT::CRML_GPU_Memory() : ChargeGPUMemory<numtyp,acctyp>(),

                                    _allocated(false) {

}

template <class numtyp, class acctyp>

CRML_GPU_MemoryT::~CRML_GPU_Memory() {

  clear();

}

template <class numtyp, class acctyp>

int CRML_GPU_MemoryT::bytes_per_atom(const int max_nbors) const {

  return this->bytes_per_atom_atomic(max_nbors);

}

template <class numtyp, class acctyp>

bool CRML_GPU_MemoryT::init(const int ntypes,

                           double host_cut_bothsq, double **host_lj1, 

                           double **host_lj2, double **host_lj3, 

                           double **host_lj4, double **host_offset, 

                           double *host_special_lj, const int nlocal,

                           const int nall, const int max_nbors,

                           const int maxspecial, const double cell_size,

                           const double gpu_split, FILE *_screen,

                           double host_cut_ljsq, const double host_cut_coulsq,

                           double *host_special_coul, const double qqrd2e,

                           const double g_ewald, const double cut_lj_innersq,

                           const double denom_lj, double **epsilon,

                           double **sigma, const bool mix_arithmetic) {

  this->init_atomic(nlocal,nall,max_nbors,maxspecial,cell_size,gpu_split,

                    _screen,crml_gpu_kernel);

  // If atom type constants fit in shared memory use fast kernel

  int lj_types=ntypes;

  shared_types=false;

  if (this->_block_size>=64 && mix_arithmetic)

    shared_types=true;

  _lj_types=lj_types;

  // Allocate a host write buffer for data initialization

  int h_size=lj_types*lj_types;

  if (h_size<MAX_BIO_SHARED_TYPES)

    h_size=MAX_BIO_SHARED_TYPES;

  UCL_H_Vec<numtyp> host_write(h_size*32,*(this->ucl_device),

                               UCL_WRITE_OPTIMIZED);

  for (int i=0; i<h_size*32; i++)

    host_write[i]=0.0;

  lj1.alloc(lj_types*lj_types,*(this->ucl_device),UCL_READ_ONLY);

  this->atom->type_pack4(ntypes,lj_types,lj1,host_write,host_lj1,host_lj2,

                         host_lj3,host_lj4);

  ljd.alloc(MAX_BIO_SHARED_TYPES,*(this->ucl_device),UCL_READ_ONLY);

  this->atom->self_pack2(ntypes,ljd,host_write,epsilon,sigma);

  sp_lj.alloc(8,*(this->ucl_device),UCL_READ_ONLY);

  for (int i=0; i<4; i++) {

    host_write[i]=host_special_lj[i];

    host_write[i+4]=host_special_coul[i];

  }

  ucl_copy(sp_lj,host_write,8,false);

  _cut_bothsq = host_cut_bothsq;

  _cut_coulsq = host_cut_coulsq;

  _cut_ljsq = host_cut_ljsq;

  _cut_lj_innersq = cut_lj_innersq;

  _qqrd2e=qqrd2e;

  _g_ewald=g_ewald;

  _denom_lj=denom_lj;

  _allocated=true;

  this->_max_bytes=lj1.row_bytes()+ljd.row_bytes()+sp_lj.row_bytes();

  return true;

}

template <class numtyp, class acctyp>

void CRML_GPU_MemoryT::clear() {

  if (!_allocated)

    return;

  _allocated=false;

  lj1.clear();

  ljd.clear();

  sp_lj.clear();

  this->clear_atomic();

}

template <class numtyp, class acctyp>

double CRML_GPU_MemoryT::host_memory_usage() const {

  return this->host_memory_usage_atomic()+sizeof(CRML_GPU_Memory<numtyp,acctyp>);

}

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

// Calculate energies, forces, and torques

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

template <class numtyp, class acctyp>

void CRML_GPU_MemoryT::loop(const bool _eflag, const bool _vflag) {

  // Compute the block size and grid size to keep all cores busy

  const int BX=this->block_size();

  int eflag, vflag;

  if (_eflag)

    eflag=1;

  else

    eflag=0;

  if (_vflag)

    vflag=1;

  else

    vflag=0;

  int GX=static_cast<int>(ceil(static_cast<double>(this->atom->inum())/BX));

  int ainum=this->atom->inum();

  int anall=this->atom->nall();

  int nbor_pitch=this->nbor->nbor_pitch();

  this->time_pair.start();

  if (shared_types) {

    this->k_pair_fast.set_size(GX,BX);

    this->k_pair_fast.run(&this->atom->dev_x.begin(), &ljd.begin(),

                          &sp_lj.begin(), &this->nbor->dev_nbor.begin(),

                          &this->atom->dev_ans.begin(),

                          &this->atom->dev_engv.begin(), &eflag, &vflag,

                          &ainum, &anall, &nbor_pitch,

                          &this->atom->dev_q.begin(), &_cut_coulsq,

                          &_qqrd2e, &_g_ewald, &_denom_lj, &_cut_bothsq,

                          &_cut_ljsq, &_cut_lj_innersq);

  } else {

    this->k_pair.set_size(GX,BX);

    this->k_pair.run(&this->atom->dev_x.begin(), &lj1.begin(),

                     &_lj_types, &sp_lj.begin(), &this->nbor->dev_nbor.begin(),

                     &this->atom->dev_ans.begin(),

                     &this->atom->dev_engv.begin(), &eflag, &vflag, &ainum,

                     &anall, &nbor_pitch, &this->atom->dev_q.begin(),

                     &_cut_coulsq, &_qqrd2e, &_g_ewald, &_denom_lj,

                     &_cut_bothsq, &_cut_ljsq, &_cut_lj_innersq);

  }

  this->time_pair.stop();

}

template class CRML_GPU_Memory<PRECISION,ACC_PRECISION>;

/* ----------------------------------------------------------------------

   LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator

   http://lammps.sandia.gov, Sandia National Laboratories

   Steve Plimpton, sjplimp@sandia.gov

   Copyright (2003) Sandia Corporation.  Under the terms of Contract

   DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains

   certain rights in this software.  This software is distributed under 

   the GNU General Public License.

   See the README file in the top-level LAMMPS directory.

------------------------------------------------------------------------- */

/* ----------------------------------------------------------------------

   Contributing authors: Mike Brown (ORNL), brownw@ornl.gov

------------------------------------------------------------------------- */

#ifndef CRML_GPU_MEMORY_H

#define CRML_GPU_MEMORY_H

#include "charge_gpu_memory.h"

template <class numtyp, class acctyp>

class CRML_GPU_Memory : public ChargeGPUMemory<numtyp, acctyp> {

 public:

  CRML_GPU_Memory();

  ~CRML_GPU_Memory();

  /// Clear any previous data and set up for a new LAMMPS run

  /** \param max_nbors initial number of rows in the neighbor matrix

    * \param cell_size cutoff + skin

    * \param gpu_split fraction of particles handled by device **/

  bool init(const int ntypes, double host_cut_bothsq,

            double **host_lj1, double **host_lj2, double **host_lj3,

            double **host_lj4, double **host_offset, double *host_special_lj,

            const int nlocal, const int nall, const int max_nbors, 

            const int maxspecial, const double cell_size, 

            const double gpu_split, FILE *screen, double host_cut_ljsq,

            const double host_cut_coulsq, double *host_special_coul,

            const double qqrd2e, const double g_ewald,

            const double cut_lj_innersq, const double denom_lj, 

            double **epsilon, double **sigma, const bool mix_arithmetic);

  /// Clear all host and device data

  /** \note This is called at the beginning of the init() routine **/

  void clear();

  /// Returns memory usage on device per atom

  int bytes_per_atom(const int max_nbors) const;

  /// Total host memory used by library for pair style

  double host_memory_usage() const;

  // --------------------------- TYPE DATA --------------------------

  /// x = lj1, y = lj2, z = lj3, w = lj4

  UCL_D_Vec<numtyp4> lj1;

  /// x = epsilon, y = sigma

  UCL_D_Vec<numtyp2> ljd;

  /// Special LJ values [0-3] and Special Coul values [4-7]

  UCL_D_Vec<numtyp> sp_lj;

  /// If atom type constants fit in shared memory, use fast kernels

  bool shared_types;

  /// Number of atom types 

  int _lj_types;

  numtyp _qqrd2e, _g_ewald, _denom_lj;

  numtyp _cut_coulsq, _cut_bothsq, _cut_ljsq, _cut_lj_innersq;

 private:

  bool _allocated;

  void loop(const bool _eflag, const bool _vflag);

};

#endif