Feb2021 GPU Package Update - GPU Package Files

lib/gpu/lal_charmm.h

@@ -0,0 +1,89 @@
+/***************************************************************************
+                                charmm.h
+                             -------------------
+                            W. Michael Brown (ORNL)
+
+  Class for acceleration of the charmm/coul pair style.
+
+ __________________________________________________________________________
+    This file is part of the LAMMPS Accelerator Library (LAMMPS_AL)
+ __________________________________________________________________________
+
+    begin                :
+    email                : brownw@ornl.gov
+ ***************************************************************************/
+
+#ifndef LAL_CHARMM_
+#define LAL_CHARMM_
+
+#include "lal_base_charge.h"
+
+namespace LAMMPS_AL {
+
+template <class numtyp, class acctyp>
+class CHARMM : public BaseCharge<numtyp, acctyp> {
+ public:
+  CHARMM();
+  ~CHARMM();
+
+  /// 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
+    *
+    * Returns:
+    * -  0 if successfull
+    * - -1 if fix gpu not found
+    * - -3 if there is an out of memory error
+    * - -4 if the GPU library was not compiled for GPU
+    * - -5 Double precision is not supported on card **/
+  int init(const int ntypes, double host_cut_bothsq,
+           double **host_lj1, double **host_lj2, double **host_lj3,
+           double **host_lj4, 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 cut_lj_innersq,
+           const double cut_coul_innersq, const double denom_lj,
+           const double denom_coul, 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, _denom_lj, _denom_coul;
+
+  numtyp _cut_coulsq, _cut_bothsq, _cut_ljsq, _cut_lj_innersq;
+  numtyp _cut_coul_innersq;
+
+ private:
+  bool _allocated;
+  int loop(const int eflag, const int vflag);
+};
+
+}
+
+#endif