#!/bin/sh

# simulator builder script
#
# warning: this MUST NOT be called directly by the user
#
# bsc invokes
#   bsc_build_vsim_... detect
# to detect whether this simulator can be built (exit status 0 = yes)
#
# bsc invokes
#   bsc_build_vsim_... link outexe topmod clibpath clibs linkopts vdirs vdefs vopts vfiles ofiles
# where
#   outexe   - the name of the simulator executable to create
#   topmod   - the toplevel module to simulate
#   clibpath - where to find external C libraries
#   clibs    - which external C libraries to link in
#   linkopts - other options passed to C/C++ linker
#   vdirs    - -y directories to search for Verilog files
#   vdefs    - -D macro definitions
#   vopts    - other options passed to Verilog
#   vfiles   - the Verilog files to simulate
#   ofiles   - any VPI object files to link in
# exits with status 0 if it successfully built the simulator, 1 otherwise

# tested on ISE 11.3

BSC_COMMAND=$1           # "detect" or "link"

if [ "$BSC_COMMAND" = "detect" ]; then
# detect whether the commands "xvlog", "xvhdl", and "xelab" are in the path
  SIM_NAME=xsim
  hash xvlog 2> /dev/null
  if [ "$?" != "0" ]; then
      echo "$SIM_NAME was not found"
      exit 1
  fi
  hash xvhdl 2> /dev/null
  if [ "$?" != "0" ]; then
      echo "$SIM_NAME was not found"
      exit 1
  fi
  hash xelab 2> /dev/null
  if [ "$?" != "0" ]; then
      echo "$SIM_NAME was not found"
      exit 1
  fi
  FOUND_CMD=`which xelab`
  echo "$SIM_NAME was found at $FOUND_CMD"
  exit 0
fi

# the only remaining command is "link"
if [ "$BSC_COMMAND" != "link" ]; then
  echo "ERROR: unknown command: $BSC_COMMAND" >&2
  exit 1
fi

BSC_SIM_EXECUTABLE=$2    # output executable filename
BSC_TOPLEVEL_MODULE=$3   # toplevel module to simulate

shift 3
BSC_VERILOG_FILES=""     # Verilog files to link
BSC_VHDL_FILES=""        # VHDL files to link
BSC_VERILOG_DIRS=""      # Verilog directories to link
BSC_VPI_FILES=""         # VPI object files to link in
BSC_C_LIB_PATH=""        # where to find C libraries for linking
BSC_C_LIBS=""            # which C files to link in
BSC_CLINK_OPTS=""        # C/C++ link options specified with -Xl in bsc
BSC_VERILOG_DEFS=""      # -D macro and -D macro=val to be passed to Verilog
BSC_VERILOG_OPTS=""      # Verilog link options specified with -Xv in bsc
BSC_OTHER_ARGUMENTS=""

VERBOSE="no"

USEDPI="no"

while [ $# -gt 0 ]; do
  if [ "${1%%.v}" != "$1" ]; then
    BSC_VERILOG_FILES="$BSC_VERILOG_FILES $1"
  elif [ "${1%%.V}" != "$1" ]; then
    BSC_VERILOG_FILES="$BSC_VERILOG_FILES $1"
  elif [ "${1%%.sv}" != "$1" ]; then
    BSC_VERILOG_FILES="$BSC_VERILOG_FILES $1"
  elif [ "${1%%.vhd}" != "$1" ]; then
    BSC_VHDL_FILES="$BSC_VHDL_FILES $1"
  elif [ "${1%%.vhdl}" != "$1" ]; then
    BSC_VHDL_FILES="$BSC_VHDL_FILES $1"
  elif [ "${1%%.o}" != "$1" ]; then
    BSC_VPI_FILES="$BSC_VPI_FILES $1"
  elif [ "$1" = "-L" ]; then
    shift 1
    BSC_C_LIB_PATH="$BSC_C_LIB_PATH -L$1"
  elif [ "$1" = "-y" ]; then
    shift 1
    BSC_VERILOG_DIRS="$BSC_VERILOG_DIRS -sourcelibdir $1"
  elif [ "$1" = "-l" ]; then
    shift 1
    BSC_C_LIBS="$BSC_C_LIBS -l$1"
  elif [ "$1" = "-Xl" ]; then
    shift 1
    BSC_CLINK_OPTS="$BSC_CLINK_OPTS $1"
  elif [ "$1" = "-D" ]; then
    shift 1
    BSC_VERILOG_DEFS="$BSC_VERILOG_DEFS -d $1"
  elif [ "$1" = "-Xv" ]; then
    shift 1
    BSC_VERILOG_OPTS="$BSC_VERILOG_OPTS $1"
  elif [ "$1" = "-verbose" ]; then
    VERBOSE="yes"
  elif [ "$1" = "-dpi" ]; then
    USEDPI="yes"
  else
    BSC_OTHER_ARGUMENTS="$BSC_OTHER_ARGUMENTS $1";
  fi
  shift 1
done

# name of xsim work directory
work_dir="work_$BSC_TOPLEVEL_MODULE"

if [ -z "$BSC_SIM_EXECUTABLE" ]; then
  echo "ERROR: simulator executable filename not specified"
  exit 1
fi

if [ -z "$BSC_TOPLEVEL_MODULE" ]; then
  echo "ERROR: no top-level module specified" >&2
  exit 1
fi

if [ -z "$BSC_VERILOG_FILES" ]; then
  echo "ERROR: no Verilog files to link" >&2
  exit 1
fi

if [ -n "$BSC_OTHER_ARGUMENTS" ]; then
  echo "ERROR: unrecognized arguments '$BSC_OTHER_ARGUMENTS'" >&2
  exit 1
fi

# XSIM doesn't support VPI
if [ -n "$BSC_VPI_FILES" ]; then
  echo "ERROR: XSim linking does not yet support VPI/DPI."
  echo "       Designs using foreign functions cannot use XSim linking."
  exit 1
fi

# path to Verilog files
VSIM_PATH_FLAGS="$BSC_VERILOG_DIRS -sourcelibext .v"

# generate a project file
TEMPFILE=`mktemp -t xsim.prj.XXXXXX` || exit 1
for file in $BSC_VERILOG_FILES; do
    abs_file=`readlink -m "$file"`
    echo "verilog $work_dir $abs_file" >> $TEMPFILE
done
for file in $BSC_VHDL_FILES; do
    abs_file=`readlink -m "$file"`
    echo "vhdl    $work_dir $abs_file" >> $TEMPFILE
done
# add glbl.v so that UNISIM models work
if [ -r $XILINX/verilog/src/glbl.v ]; then
    abs_file=`readlink -m "$XILINX/verilog/src/glbl.v"`
    echo "verilog $work_dir $abs_file" >> $TEMPFILE
    UNISIM_FLAGS="-L unisims_ver -t $work_dir.glbl"
else
    UNISIM_FLAGS=""
fi

# run xelab to build a simulation executable
XELAB_DEBUG="-debug typical" # the default debug level is "off" which does not allow VCD dumping.  See UG900 xelab opts
if [ "$VERBOSE" = "yes" ]; then
  XELAB_VERBOSE="-v 2"
  echo "exec: xelab $XELAB_VERBOSE $XELAB_DEBUG -s $BSC_SIM_EXECUTABLE.xsim -prj $TEMPFILE $VSIM_PATH_FLAGS $BSC_VSIM_FLAGS -d TOP=$BSC_TOPLEVEL_MODULE $BSC_VERILOG_DEFS $UNISIM_FLAGS -t $work_dir.main $BSC_VERILOG_OPTS"
else
  XELAB_VERBOSE="-v 0"
fi
xelab $XELAB_VERBOSE $XELAB_DEBUG -s $BSC_SIM_EXECUTABLE.xsim -prj $TEMPFILE $VSIM_PATH_FLAGS $BSC_VSIM_FLAGS -d TOP=$BSC_TOPLEVEL_MODULE $BSC_VERILOG_DEFS $UNISIM_FLAGS -t $work_dir.main $BSC_VERILOG_OPTS
status=$?
if [ "$status" != "0" ]; then
  echo "ERROR: cannot compile HDL files" >&2
  exit $status
fi

# create a TCL command file to run the simulation
echo "run all" > $BSC_SIM_EXECUTABLE.xsim.tcl
echo "quit" >> $BSC_SIM_EXECUTABLE.xsim.tcl

# create a "simulator executable" shell script
rm -f $BSC_SIM_EXECUTABLE
status=$?
if [ "$status" != "0" ]; then
  echo "ERROR: cannot create $BSC_SIM_EXECUTABLE" >&2
  exit $status
fi
echo '#!/bin/sh' > $BSC_SIM_EXECUTABLE
echo "xsim $BSC_SIM_EXECUTABLE.xsim -tclbatch $BSC_SIM_EXECUTABLE.xsim.tcl \$*" >> $BSC_SIM_EXECUTABLE
echo 'status=$?' >> $BSC_SIM_EXECUTABLE
echo 'if [ "$status" != "0" ]; then' >> $BSC_SIM_EXECUTABLE
echo '    echo "ERROR: cannot simulate design" >&2' >> $BSC_SIM_EXECUTABLE
echo '    exit $status' >> $BSC_SIM_EXECUTABLE
echo 'fi' >> $BSC_SIM_EXECUTABLE
chmod +x $BSC_SIM_EXECUTABLE

# cleanup by removing the xsim.prj.XXXXXX file
rm -f $TEMPFILE