basic framework

peakrdl/regblock/signals.py

@@ -0,0 +1,90 @@
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from systemrdl import SignalNode
+
+class SignalBase:
+
+    @property
+    def is_async(self) -> bool:
+        raise NotImplementedError()
+
+    @property
+    def is_activehigh(self) -> bool:
+        raise NotImplementedError()
+
+    @property
+    def width(self) -> int:
+        raise NotImplementedError()
+
+    @property
+    def identifier(self) -> str:
+        raise NotImplementedError()
+
+    @property
+    def activehigh_identifier(self) -> str:
+        """
+        Normalizes the identifier reference to be active-high logic
+        """
+        if not self.is_activehigh:
+            return "~%s" % self.identifier
+        return self.identifier
+
+    @property
+    def port_declaration(self) -> str:
+        """
+        Returns the port delcaration text for this signal.
+        In the context of this exporter, all signal objects happen to be inputs.
+        """
+        if self.width > 1:
+            return "input wire [%d:0] %s" % (self.width - 1, self.identifier)
+        return "input wire %s" % self.identifier
+
+
+class RDLSignal(SignalBase):
+    """
+    Wrapper around a SystemRDL signal object
+    """
+    def __init__(self, rdl_signal:'SignalNode'):
+        self.rdl_signal = rdl_signal
+
+    @property
+    def is_async(self) -> bool:
+        return self.rdl_signal.get_property("async")
+
+    @property
+    def is_activehigh(self) -> bool:
+        return self.rdl_signal.get_property("activehigh")
+
+    @property
+    def width(self) -> int:
+        return self.rdl_signal.width
+
+    @property
+    def identifier(self) -> str:
+        # TODO: uniquify this somehow
+        # TODO: Deal with different hierarchies
+        return "TODO_%s" % self.rdl_signal.inst_name
+
+
+class InferredSignal(SignalBase):
+    def __init__(self, identifier:str, width:int=1, is_async:bool=False):
+        self._identifier = identifier
+        self._width = width
+        self._is_async = is_async
+
+    @property
+    def is_async(self) -> bool:
+        return self._is_async
+
+    @property
+    def is_activehigh(self) -> bool:
+        return True
+
+    @property
+    def width(self) -> int:
+        return self._width
+
+    @property
+    def identifier(self) -> str:
+        return self._identifier