Add types and test for implementing ringbuffer abstractions in rust

bittide-instances/tests/Wishbone/ScatterGather.hs

@@ -73,5 +73,31 @@ case_scatter_gather_c_test = do
  where
   msg = "Received the following from the CPU over UART:\n" <> simResultC
 
+-- Aligned ringbuffer test simulation
+simAlignedRingbuffer :: IO ()
+simAlignedRingbuffer = putStr simResultAlignedRingbuffer
+
+simResultAlignedRingbuffer :: (HasCallStack) => String
+simResultAlignedRingbuffer = chr . fromIntegral <$> catMaybes uartStream
+ where
+  uartStream = sampleC def{timeoutAfter = 200_000} dutNoMM
+
+  dutNoMM :: (HasCallStack) => Circuit () (Df System (BitVector 8))
+  dutNoMM = circuit $ do
+    mm <- ignoreMM
+    uartTx <-
+      withClockResetEnable clockGen (resetGenN d2) enableGen
+        $ (dutWithBinary "aligned_ringbuffer_test")
+        -< mm
+    idC -< uartTx
+
+case_aligned_ringbuffer_test :: Assertion
+case_aligned_ringbuffer_test = do
+  assertBool
+    msg
+    ("*** ALL TESTS PASSED ***" `isInfixOf` simResultAlignedRingbuffer)
+ where
+  msg = "Received the following from the CPU over UART:\n" <> simResultAlignedRingbuffer
+
 tests :: TestTree
 tests = $(testGroupGenerator)

firmware-binaries/Cargo.toml

@@ -16,6 +16,7 @@ members = [
   "examples/c_hello",
   "examples/smoltcp_client",
 
+  "sim-tests/aligned_ringbuffer_test",
   "sim-tests/axi_stream_self_test",
   "sim-tests/registerwb_test",
   "sim-tests/capture_ugn_test",

firmware-binaries/sim-tests/aligned_ringbuffer_test/Cargo.toml

@@ -0,0 +1,21 @@
+# SPDX-FileCopyrightText: 2025 Google LLC
+#
+# SPDX-License-Identifier: CC0-1.0
+
+[package]
+name = "aligned_ringbuffer_test"
+version = "0.1.0"
+edition = "2021"
+license = "Apache-2.0"
+authors = ["Google LLC"]
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+riscv-rt = "0.11.0"
+bittide-sys = { path = "../../../firmware-support/bittide-sys" }
+bittide-hal = { path = "../../../firmware-support/bittide-hal" }
+ufmt = "0.2.0"
+
+[build-dependencies]
+memmap-generate = { path = "../../../firmware-support/memmap-generate" }

firmware-binaries/sim-tests/aligned_ringbuffer_test/build.rs

@@ -0,0 +1,10 @@
+// SPDX-FileCopyrightText: 2025 Google LLC
+//
+// SPDX-License-Identifier: Apache-2.0
+
+use memmap_generate::build_utils::standard_memmap_build;
+
+fn main() {
+    standard_memmap_build("ScatterGatherPe.json", "DataMemory", "InstructionMemory");
+    println!("cargo:rerun-if-changed=build.rs");
+}

firmware-binaries/sim-tests/aligned_ringbuffer_test/memory.x

@@ -0,0 +1,18 @@
+/*
+SPDX-FileCopyrightText: 2025 Google LLC
+
+SPDX-License-Identifier: CC0-1.0
+*/
+
+MEMORY
+{
+  IMEM : ORIGIN = 0x80000000, LENGTH = 64K
+  DMEM : ORIGIN = 0x20000000, LENGTH = 32K
+}
+
+REGION_ALIAS("REGION_TEXT", IMEM);
+REGION_ALIAS("REGION_RODATA", DMEM);
+REGION_ALIAS("REGION_DATA", DMEM);
+REGION_ALIAS("REGION_BSS", DMEM);
+REGION_ALIAS("REGION_HEAP", DMEM);
+REGION_ALIAS("REGION_STACK", DMEM);