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Docs: Shorten cmd:ref

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Krystine Sherwin 2024-05-03 13:16:48 +12:00
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docs/source/using_yosys/synthesis/memory.rst
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@ -1,11 +1,11 @@
Memory handling
===============
The :cmd:ref:`memory` command
The `memory` command
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
In the RTL netlist, memory reads and writes are individual cells. This makes
consolidating the number of ports for a memory easier. The :cmd:ref:`memory`
consolidating the number of ports for a memory easier. The `memory`
pass transforms memories to an implementation. Per default that is logic for
address decoders and registers. It also is a macro command that calls the other
common ``memory_*`` passes in a sensible order:
@ -13,19 +13,19 @@ common ``memory_*`` passes in a sensible order:
.. literalinclude:: /code_examples/macro_commands/memory.ys
:language: yoscrypt
:start-after: #end:
:caption: Passes called by :cmd:ref:`memory`
:caption: Passes called by `memory`
.. todo:: Make ``memory_*`` notes less quick
Some quick notes:
- :cmd:ref:`memory_dff` merges registers into the memory read- and write cells.
- :cmd:ref:`memory_collect` collects all read and write cells for a memory and
- `memory_dff` merges registers into the memory read- and write cells.
- `memory_collect` collects all read and write cells for a memory and
transforms them into one multi-port memory cell.
- :cmd:ref:`memory_map` takes the multi-port memory cell and transforms it to
- `memory_map` takes the multi-port memory cell and transforms it to
address decoder logic and registers.
For more information about :cmd:ref:`memory`, such as disabling certain sub
For more information about `memory`, such as disabling certain sub
commands, see :doc:`/cmd/memory`.
Example
@ -75,22 +75,22 @@ For example:
techmap -map my_memory_map.v
memory_map
:cmd:ref:`memory_libmap` attempts to convert memory cells (`$mem_v2` etc) into
`memory_libmap` attempts to convert memory cells (`$mem_v2` etc) into
hardware supported memory using a provided library (:file:`my_memory_map.txt` in the
example above). Where necessary, emulation logic is added to ensure functional
equivalence before and after this conversion. :yoscrypt:`techmap -map
my_memory_map.v` then uses :cmd:ref:`techmap` to map to hardware primitives. Any
my_memory_map.v` then uses `techmap` to map to hardware primitives. Any
leftover memory cells unable to be converted are then picked up by
:cmd:ref:`memory_map` and mapped to DFFs and address decoders.
`memory_map` and mapped to DFFs and address decoders.
.. note::
More information about what mapping options are available and associated
costs of each can be found by enabling debug outputs. This can be done with
the :cmd:ref:`debug` command, or by using the ``-g`` flag when calling Yosys
the `debug` command, or by using the ``-g`` flag when calling Yosys
to globally enable debug messages.
For more on the lib format for :cmd:ref:`memory_libmap`, see
For more on the lib format for `memory_libmap`, see
`passes/memory/memlib.md
<https://github.com/YosysHQ/yosys/blob/main/passes/memory/memlib.md>`_