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small clarifications + cleanup [skip ci]

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abejgonzalez
2019-09-20 12:22:39 -07:00
parent 37b934236a
commit edaf99ca9a
9 changed files with 36 additions and 59 deletions
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54
docs/Customization/Heterogeneous-SoCs.rst
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@@ -12,18 +12,10 @@ Both BOOM and Rocket have mixins labelled ``WithNBoomCores(X)`` and ``WithNBigCo
When used together you can create a heterogeneous system.
The following example shows a dual core BOOM with a single core Rocket.
.. code-block:: scala
class DualBoomAndOneRocketConfig extends Config(
new WithTop ++
new WithBootROM ++
new boom.system.WithRenumberHarts ++
new boom.common.WithRVC ++
new boom.common.LargeBoomConfig ++
new boom.system.WithNBoomCores(2) ++
new freechips.rocketchip.subsystem.WithoutTLMonitors ++
new freechips.rocketchip.subsystem.WithNBigCores(1) ++
new freechips.rocketchip.system.BaseConfig)
.. literalinclude:: ../../generators/example/src/main/scala/HeteroConfigs.scala
:language: scala
:start-after: DOC include start: DualBoomAndRocket
:end-before: DOC include end: DualBoomAndRocket
In this example, the ``WithNBoomCores`` and ``WithNBigCores`` mixins set up the default parameters for the multiple BOOM and Rocket cores, respectively.
However, for BOOM, an extra mixin called ``LargeBoomConfig`` is added to override the default parameters with a different set of more common default parameters.
@@ -75,19 +67,10 @@ Adding Hwachas
Adding a Hwacha accelerator is as easy as adding the ``DefaultHwachaConfig`` so that it can setup the Hwacha parameters and add itself to the ``BuildRoCC`` parameter.
An example of adding a Hwacha to all tiles in the system is below.
.. code-block:: scala
class DualBoomAndRocketWithHwachasConfig extends Config(
new WithTop ++
new WithBootROM ++
new hwacha.DefaultHwachaConfig ++
new boom.system.WithRenumberHarts ++
new boom.common.WithRVC ++
new boom.common.LargeBoomConfig ++
new boom.system.WithNBoomCores(2) ++
new freechips.rocketchip.subsystem.WithoutTLMonitors ++
new freechips.rocketchip.subsystem.WithNBigCores(1) ++
new freechips.rocketchip.system.BaseConfig)
.. literalinclude:: ../../generators/example/src/main/scala/HeteroConfigs.scala
:language: scala
:start-after: DOC include start: BoomAndRocketWithHwacha
:end-before: DOC include end: BoomAndRocketWithHwacha
In this example, Hwachas are added to both BOOM tiles and to the Rocket tile.
All with the same Hwacha parameters.
@@ -100,24 +83,13 @@ Named ``MultiRoCCKey``, this key allows you to attach RoCC accelerators based on
For example, using this allows you to create a 8 tile system with a RoCC accelerator on only a subset of the tiles.
An example is shown below with two BOOM cores, and one Rocket tile with a RoCC accelerator (Hwacha) attached.
.. code-block:: scala
class DualBoomAndOneHwachaRocketConfig extends Config(
new WithTop ++
new WithBootROM ++
new WithMultiRoCC ++
new WithMultiRoCCHwacha(0) ++ // put Hwacha just on hart0 which was renumbered to Rocket
new boom.system.WithRenumberHarts(rocketFirst = true) ++
new hwacha.DefaultHwachaConfig ++
new boom.common.WithRVC ++
new boom.common.LargeBoomConfig ++
new boom.system.WithNBoomCores(2) ++
new freechips.rocketchip.subsystem.WithoutTLMonitors ++
new freechips.rocketchip.subsystem.WithNBigCores(1) ++
new freechips.rocketchip.system.BaseConfig)
.. literalinclude:: ../../generators/example/src/main/scala/HeteroConfigs.scala
:language: scala
:start-after: DOC include start: DualBoomAndRocketOneHwacha
:end-before: DOC include end: DualBoomAndRocketOneHwacha
In this example, the ``WithRenumberHarts`` relabels the ``hartId``'s of all the BOOM/Rocket cores.
Then after that is applied to the parameters, the ``WithMultiRoCCHwacha(0)`` is used to assign to ``hartId`` zero a Hwacha (in this case ``hartId`` zero is Rocket).
Then after that is applied to the parameters, the ``WithMultiRoCCHwacha`` is used to assign to a Hwacha accelerator to a particular ``hartId`` (in this case the ``hartId`` corresponding to Rocket).
Finally, the ``WithMultiRoCC`` mixin is called.
This mixin sets the ``BuildRoCC`` key to use the ``MultiRoCCKey`` instead of the default.
This must be used after all the RoCC parameters are set because it needs to override the ``BuildRoCC`` parameter.