External Transactron (#758)

.github/workflows/benchmark.yml

@@ -36,9 +36,6 @@ jobs:
           # https://github.com/actions/runner/issues/2033
           chown -R $(id -u):$(id -g) $PWD
 
-      - name: Checkout submodules
-        run: git submodule update --init --recursive amaranth-stubs
-
       - name: Set up Python
         uses: actions/setup-python@v5
         with:
@@ -114,9 +111,6 @@ jobs:
           # https://github.com/actions/runner/issues/2033
           chown -R $(id -u):$(id -g) $PWD
 
-      - name: Checkout submodules
-        run: git submodule update --init --recursive amaranth-stubs
-
       - name: Set up Python
         uses: actions/setup-python@v5
         with:
@@ -165,9 +159,6 @@ jobs:
           # https://github.com/actions/runner/issues/2033
           chown -R $(id -u):$(id -g) $PWD
 
-      - name: Checkout submodules
-        run: git submodule update --init --recursive amaranth-stubs
-
       - name: Set up Python
         uses: actions/setup-python@v5
         with:

.github/workflows/deploy_gh_pages.yml

@@ -23,9 +23,6 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
 
-      - name: Checkout submodules
-        run: git submodule update --init --recursive amaranth-stubs
-
       - name: Set up Python
         uses: actions/setup-python@v5
         with:

.github/workflows/main.yml

@@ -20,9 +20,6 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
 
-      - name: Checkout submodules
-        run: git submodule update --init --recursive amaranth-stubs
-
       - name: Set up Python
         uses: actions/setup-python@v5
         with:
@@ -153,9 +150,6 @@ jobs:
           git config --global --add safe.directory /__w/coreblocks/coreblocks
           git submodule > .gitmodules-hash
 
-      - name: Checkout submodules
-        run: git submodule update --init --recursive amaranth-stubs
-
       - name: Set up Python
         uses: actions/setup-python@v5
         with:
@@ -263,9 +257,6 @@ jobs:
           git config --global --add safe.directory /__w/coreblocks/coreblocks
           git submodule > .gitmodules-hash
 
-      - name: Checkout submodules
-        run: git submodule update --init --recursive amaranth-stubs
-
       - name: Set up Python
         uses: actions/setup-python@v5
         with:
@@ -318,9 +309,6 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
 
-      - name: Checkout submodules
-        run: git submodule update --init --recursive amaranth-stubs
-
       - name: Set up Python
         uses: actions/setup-python@v5
         with:
@@ -353,9 +341,6 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
 
-      - name: Checkout submodules
-        run: git submodule update --init --recursive amaranth-stubs
-
       - name: Set up Python
         uses: actions/setup-python@v5
         with:

.gitmodules

@@ -8,6 +8,3 @@
 [submodule "test/external/riscof/riscv-arch-test"]
 	path = test/external/riscof/riscv-arch-test
 	url = https://github.com/riscv-non-isa/riscv-arch-test.git
-[submodule "amaranth-stubs"]
-	path = amaranth-stubs
-	url = https://github.com/kuznia-rdzeni/amaranth-stubs.git

README.md

@@ -9,7 +9,7 @@ Coreblocks is an experimental, modular out-of-order [RISC-V](https://riscv.org/s
  * Simplicity. Coreblocks is an academic project, accessible to students.
    It should be suitable for teaching essentials of out-of-order architectures.
  * Modularity. We want to be able to easily experiment with the core by adding, replacing and modifying modules without changing the source too much.
-   For this goal, we designed a [transaction system](https://kuznia-rdzeni.github.io/coreblocks/Transactions.html) inspired by [Bluespec](http://wiki.bluespec.com/).
+   For this goal, we designed a transaction system called [Transactron](https://github.com/kuznia-rdzeni/transactron), which is inspired by [Bluespec](http://wiki.bluespec.com/).
  * Fine-grained testing. Outside of the integration tests for the full core, modules are tested individually.
    This is to support an agile style of development.
 
@@ -25,9 +25,6 @@ The core currently supports the full RV32I instruction set and several extension
 Exceptions and some of machine-mode CSRs are supported, the support for interrupts is currently rudimentary and incompatible with the RISC-V spec.
 Coreblocks can be used with [LiteX](https://github.com/enjoy-digital/litex) (currently using a [patched version](https://github.com/kuznia-rdzeni/litex/tree/coreblocks)).
 
-The transaction system we use as the foundation for the core is well-tested and usable.
-We plan to make it available as a separate Python package.
-
 ## Documentation
 
 The [documentation for our project](https://kuznia-rdzeni.github.io/coreblocks/) is automatically generated using [Sphinx](https://www.sphinx-doc.org/).

coreblocks/core.py

@@ -136,8 +136,9 @@ def elaborate(self, platform):
 
         m.submodules.exception_information_register = self.exception_information_register
 
-        if self.connections.dependency_provided(FetchResumeKey()):
-            fetch_resume_fb, fetch_resume_unifiers = self.connections.get_dependency(FetchResumeKey())
+        fetch_resume = self.connections.get_optional_dependency(FetchResumeKey())
+        if fetch_resume is not None:
+            fetch_resume_fb, fetch_resume_unifiers = fetch_resume
             m.submodules.fetch_resume_unifiers = ModuleConnector(**fetch_resume_unifiers)
 
             m.submodules.fetch_resume_connector = ConnectTrans(fetch_resume_fb, self.frontend.resume_from_unsafe)

coreblocks/frontend/fetch/fetch.py

@@ -403,8 +403,9 @@ def _():
             expect_unstall_unsafe = Signal()
             prev_stalled_unsafe = Signal()
             dependencies = DependencyContext.get()
-            if dependencies.dependency_provided(FetchResumeKey()):
-                unifier_ready = DependencyContext.get().get_dependency(FetchResumeKey())[0].ready
+            fetch_resume = dependencies.get_optional_dependency(FetchResumeKey())
+            if fetch_resume is not None:
+                unifier_ready = fetch_resume[0].ready
             else:
                 unifier_ready = C(0)
 

docs/api.md

@@ -2,5 +2,4 @@
 
 ```{eval-rst}
 .. include:: modules-coreblocks.rst
-.. include:: modules-transactron.rst
 ```

docs/index.md

@@ -8,7 +8,6 @@ maxdepth: 3
 home.md
 assumptions.md
 development-environment.md
-transactions.md
 scheduler/overview.md
 shared-structs/implementation/rs-impl.md
 shared-structs/rs.md