Initial Commit - Forked from PeakRDL-regblock @ a440cc19769069be831d267505da4f3789a26695

docs/props/rhs_props.rst

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+RHS Property References
+=======================
+
+SystemRDL allows some properties to be referenced in the righthand-side of
+property assignment expressions:
+
+    .. code-block:: systemrdl
+
+            some_property = my_reg.my_field -> some_property;
+
+The official SystemRDL spec refers to these as "Ref targets" in Table G1, but
+unfortunately does not describe their semantics in much detail.
+
+The text below describes the interpretations used for this exporter.
+
+--------------------------------------------------------------------------------
+
+Field
+-----
+
+field -> swacc
+^^^^^^^^^^^^^^
+Single-cycle strobe that indicates the field is being accessed by software
+(read or write).
+
+
+field -> swmod
+^^^^^^^^^^^^^^^
+Single-cycle strobe that indicates the field is being modified during a software
+access operation.
+
+
+field -> swwe/swwel
+^^^^^^^^^^^^^^^^^^^
+Represents the signal that controls the field's swwe/swwel behavior.
+
+
+field -> anded/ored/xored
+^^^^^^^^^^^^^^^^^^^^^^^^^
+Represents the current and/or/xor reduction of the field's value.
+
+
+field -> hwclr/hwset
+^^^^^^^^^^^^^^^^^^^^
+|EX|
+
+Represents the signal that controls the field's hwclr/hwset behavior.
+
+
+field -> hwenable/hwmask
+^^^^^^^^^^^^^^^^^^^^^^^^
+Represents the signal that controls the field's hwenable/hwmask behavior.
+
+field -> we/wel
+^^^^^^^^^^^^^^^
+Represents the signal that controls the field's we/wel behavior.
+
+field -> next
+^^^^^^^^^^^^^
+|EX|
+
+field -> reset
+^^^^^^^^^^^^^^
+Represents the value that was assigned to this property.
+
+field -> resetsignal
+^^^^^^^^^^^^^^^^^^^^
+Represents the value that was assigned to this property.
+
+--------------------------------------------------------------------------------
+
+Field Counter Properties
+------------------------
+
+field -> incr
+^^^^^^^^^^^^^
+Represents the signal that controls the field's counter increment control.
+
+
+field -> incrsaturate/saturate
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Represents the internal 1-bit event signal that indicates whether the counter is saturated
+at its saturation value.
+
+.. wavedrom::
+
+    {
+        "signal": [
+            {"name": "clk",            "wave": "p......"},
+            {"name": "hwif_in..decr",  "wave": "0101010"},
+            {"name": "<counter>",      "wave": "=.=....", "data": [1,0]},
+            {"name": "<decrsaturate>", "wave": "0.1...."}
+        ],
+        "foot": {
+            "text": "A 4-bit counter saturating"
+        }
+    }
+
+
+field -> incrthreshold/threshold
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Represents the 1-bit event signal that indicates whether the counter has met or
+exceeded its incrthreshold.
+
+field -> incrvalue
+^^^^^^^^^^^^^^^^^^
+Represents the value that was assigned to this property.
+
+field -> overflow
+^^^^^^^^^^^^^^^^^
+Represents the event signal that is asserted when the counter is about to wrap.
+
+field -> decr
+^^^^^^^^^^^^^
+Represents the signal that controls the field's counter decrement control.
+
+field -> decrsaturate
+^^^^^^^^^^^^^^^^^^^^^
+Represents the internal 1-bit event signal that indicates whether the counter is saturated
+at its saturation value.
+
+.. wavedrom::
+
+    {
+        "signal": [
+            {"name": "clk",            "wave": "p......"},
+            {"name": "hwif_in..incr",  "wave": "0101010"},
+            {"name": "<counter>",      "wave": "=.=....", "data": [14,15]},
+            {"name": "<incrsaturate>", "wave": "0.1...."}
+        ],
+        "foot": {
+            "text": "A 4-bit counter saturating"
+        }
+    }
+
+field -> decrthreshold
+^^^^^^^^^^^^^^^^^^^^^^
+Represents the 1-bit event signal that indicates whether the counter has met or
+exceeded its incrthreshold.
+
+field -> decrvalue
+^^^^^^^^^^^^^^^^^^
+Represents the value that was assigned to this property.
+
+field -> underflow
+^^^^^^^^^^^^^^^^^^
+Represents the event signal that is asserted when the counter is about to wrap.
+
+--------------------------------------------------------------------------------
+
+Field Interrupt Properties
+--------------------------
+
+field -> enable
+^^^^^^^^^^^^^^^
+Represents the value that was assigned to this property.
+
+field -> mask
+^^^^^^^^^^^^^
+Represents the value that was assigned to this property.
+
+field -> haltenable
+^^^^^^^^^^^^^^^^^^^
+Represents the value that was assigned to this property.
+
+field -> haltmask
+^^^^^^^^^^^^^^^^^
+Represents the value that was assigned to this property.
+
+
+--------------------------------------------------------------------------------
+
+Register
+--------
+
+reg -> intr
+^^^^^^^^^^^
+References the register's ``hwif_out..intr`` signal.
+
+reg -> halt
+^^^^^^^^^^^
+References the register's ``hwif_out..halt`` signal.