[VERILOG] VPI RAM controler to access python memory.

include/tvm/runtime/c_runtime_api.h

@@ -38,6 +38,13 @@
 TVM_EXTERN_C {
 /*! \brief type of array index. */
 typedef int64_t tvm_index_t;
+
+/*! \brief Extension device types in TVM */
+typedef enum {
+  /*! \brief Simulated on board RAM */
+  kVPI = 9
+} TVMDeviceExtType;
+
 /*!
  * \brief The type code in TVMType
  * \note TVMType is used in two places.

include/tvm/runtime/packed_func.h

@@ -274,6 +274,7 @@ class TVMArgValue : public TVMPODValue_ {
     return value_.v_type;
   }
   operator PackedFunc() const {
+    if (type_code_ == kNull) return PackedFunc();
     TVM_CHECK_TYPE_CODE(type_code_, kFuncHandle);
     return *ptr<PackedFunc>();
   }
@@ -350,6 +351,7 @@ class TVMRetValue : public TVMPODValue_ {
     return value_.v_type;
   }
   operator PackedFunc() const {
+    if (type_code_ == kNull) return PackedFunc();
     TVM_CHECK_TYPE_CODE(type_code_, kFuncHandle);
     return *ptr<PackedFunc>();
   }

python/tvm/__init__.py

@@ -15,7 +15,7 @@
 from . import module
 
 from . import ndarray as nd
-from .ndarray import cpu, gpu, opencl, cl
+from .ndarray import cpu, gpu, opencl, cl, vpi
 
 from ._base import TVMError
 from .api import *

python/tvm/_ctypes/_ndarray.py

@@ -18,7 +18,8 @@ class TVMContext(ctypes.Structure):
     MASK2STR = {
         1 : 'cpu',
         2 : 'gpu',
-        4 : 'opencl'
+        4 : 'opencl',
+        9 : 'vpi'
     }
     def __init__(self, device_id, device_type):
         super(TVMContext, self).__init__()
@@ -76,6 +77,16 @@ def opencl(dev_id=0):
     """
     return TVMContext(dev_id, 4)
 
+def vpi(dev_id=0):
+    """Construct a VPI simulated device
+
+    Parameters
+    ----------
+    dev_id : int, optional
+        The integer device id
+    """
+    return TVMContext(dev_id, 9)
+
 
 def numpyasarray(np_data):
     """Return a TVMArray representation of a numpy array.

python/tvm/addon/verilog.py

@@ -17,6 +17,7 @@ def __init__(self, handle):
         super(VPISession, self).__init__(handle)
         self.proc = None
         self.execpath = None
+        self.yield_callbacks = []
 
     def __del__(self):
         self.proc.kill()
@@ -47,6 +48,8 @@ def __getattr__(self, name):
 
     def yield_until_posedge(self):
         """Yield until next posedge"""
+        for f in self.yield_callbacks:
+            f()
         return _api_internal._vpi_SessYield(self)
 
     def shutdown(self):
@@ -222,7 +225,16 @@ def session(file_name):
     env['TVM_HREAD_PIPE'] = str(read_host)
     env['TVM_HWRITE_PIPE'] = str(write_host)
 
-    proc = subprocess.Popen(cmd, env=env, close_fds=False)
+    try:
+        # close_fds does not work well for all python3
+        # Use pass_fds instead.
+        # pylint: disable=unexpected-keyword-arg
+        pass_fds = (read_device, write_device, read_host, write_host)
+        proc = subprocess.Popen(cmd, pass_fds=pass_fds, env=env)
+    except TypeError:
+        # This is effective for python2
+        proc = subprocess.Popen(cmd, close_fds=False, env=env)
+
     # close device side pipe
     os.close(read_device)
     os.close(write_device)

python/tvm/ndarray.py

@@ -7,7 +7,7 @@
 import numpy as _np
 
 from ._ctypes._ndarray import TVMContext, TVMType, NDArrayBase
-from ._ctypes._ndarray import cpu, gpu, opencl, empty, sync
+from ._ctypes._ndarray import cpu, gpu, opencl, vpi, empty, sync
 from ._ctypes._ndarray import _init_ndarray_module
 from ._ctypes._function import Function