doc update for packable XML syntax in VPR
@@ -10,10 +10,18 @@ Models, Complex blocks and Physical Tiles
Each ``<pb_type>`` should contain a ``<mode>`` that describe the physical implementation of the ``<pb_type>``. Note that this is fully compatible to the VPR architecture XML syntax.
-``<model>`` should include the models that describe the primitive ``<pb_type>`` in physical mode.
+.. note:: ``<model>`` should include the models that describe the primitive ``<pb_type>`` in physical mode.
.. note:: Currently, OpenFPGA only supports 1 ``<equivalent_sites>`` to be defined under each ``<tile>``
+.. option:: <mode packable="<bool">/>
+
+ OpenFPGA allows users to define it a mode is packable for VPR.
+ By default, the packable is set to ``true``.
+ This is mainly used for the mode that describes the physical implementation, which is typically not packable. Disable it in the packing and signficantly accelerate the packing runtime.
+
+ .. note:: Once a mode is set to unpackable, its child modes will be unpackable as well.
+
Layout
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