Use two versions of openocd.

openocd-vexriscv is required because openocd-riscv does not allow the CPU to be reset while openocd is connected. This is unfortunately required for the current state of swCcTopologyTest and is non-trivial to fix.

We intend to at some point remove this test case and get rid of the custom openocd version in favor of the "official" riscv version.

bittide-instances/data/openocd/start.sh

@@ -17,6 +17,6 @@ mkdir -p "${stderr_dir}"
 OPENOCD_STDERR_LOG="$(realpath ${OPENOCD_STDERR_LOG})"
 
 cd $(dirname $0)
-exec openocd-riscv -f ports.tcl -f sipeed.tcl -f vexriscv_init.tcl $@ \
+exec ${OPENOCD_BIN} -f ports.tcl -f sipeed.tcl -f vexriscv_init.tcl $@ \
   > >(tee "${OPENOCD_STDOUT_LOG}") \
   2> >(tee "${OPENOCD_STDERR_LOG}" >&2)

bittide-instances/src/Bittide/Instances/Hitl/Driver/SwCcTopologies.hs

@@ -86,7 +86,10 @@ driverFunc testName targets = do
       putStrLn "Starting OpenOCD..."
       (ocd, ocdPh, ocdClean1) <-
         startOpenOcdWithEnv
-          [("OPENOCD_STDOUT_LOG", ocdStdout), ("OPENOCD_STDERR_LOG", ocdStderr)]
+          [ ("OPENOCD_STDOUT_LOG", ocdStdout)
+          , ("OPENOCD_STDERR_LOG", ocdStderr)
+          , ("OPENOCD_BIN", "openocd-vexriscv")
+          ]
           d.usbAdapterLocation
           gdbPort
           tclPort

bittide-instances/src/Bittide/Instances/Hitl/Utils/Program.hs

@@ -101,7 +101,13 @@ startOpenOcdWithEnv ::
   -- | Telnet port
   Int ->
   IO (ProcessStdIoHandles, ProcessHandle, IO ())
-startOpenOcdWithEnv extraEnv usbLoc gdbPort tclPort telnetPort = do
+startOpenOcdWithEnv extraEnv0 usbLoc gdbPort tclPort telnetPort = do
+  -- Check if OPENOCD_BIN is set. If not, append ("OPENOCD_BIN", "openocd") to the environment.
+  -- This is necessary because swCcTopologiesTest relies on the custom OpenOCD binary.
+  let extraEnv1
+        | any ((== "OPENOCD_BIN") . fst) extraEnv0 = extraEnv0
+        | otherwise = ("OPENOCD_BIN", "openocd") : extraEnv0
+
   startOpenOcdPath <- getOpenOcdStartPath
   currentEnv <- getEnvironment
   let
@@ -113,7 +119,7 @@ startOpenOcdWithEnv extraEnv usbLoc gdbPort tclPort telnetPort = do
         , env =
             Just
               ( currentEnv
-                  <> extraEnv
+                  <> extraEnv1
                   <> [ ("USB_DEVICE", usbLoc)
                      , ("GDB_PORT", show gdbPort)
                      , ("TCL_PORT", show tclPort)

nix/bin/install-openocd-vexriscv-udev

@@ -42,5 +42,6 @@ if [ -f "${UDEV_RULES_D}/${UDEV_RULES_BASENAME}" ]; then
   echo "'${UDEV_RULES_D}/${UDEV_RULES_BASENAME}' already exists, doing nothing"
 else
   exec_print sudo cp "$OPENOCD_DIST/share/openocd/contrib/${UDEV_RULES_BASENAME}" "${UDEV_RULES_D}"
+  exec_print sudo cp "$VEXOPENOCD_DIST/share/openocd/contrib/${UDEV_RULES_BASENAME}" "${UDEV_RULES_D}"
   exec_print sudo udevadm control --reload-rules
 fi

nix/nixpkgs.nix

@@ -8,6 +8,7 @@ let
 
     verilog-ethernet = import ./verilog-ethernet.nix { inherit (nixpkgs) pkgs; };
     mc = import ./mc.nix { inherit (nixpkgs) pkgs; };
+    openocd-vexriscv = import ./openocd-vexriscv.nix { inherit (nixpkgs) pkgs; };
     openocd-riscv = import ./openocd-riscv.nix { inherit (nixpkgs) pkgs; };
 
     # Haskell overrides

nix/openocd-vexriscv.nix

@@ -0,0 +1,38 @@
+{ pkgs ? import ./nixpkgs.nix {} }:
+
+pkgs.stdenv.mkDerivation rec {
+  name = "openocd-vexriscv";
+
+  buildInputs = [
+    pkgs.autoconf
+    pkgs.automake
+    pkgs.coreutils
+    pkgs.git
+    pkgs.libtool
+    pkgs.libusb1
+    pkgs.libyaml
+    pkgs.pkg-config
+    pkgs.texinfo
+    pkgs.which
+  ];
+
+  src = pkgs.fetchgit {
+    url = "https://github.com/SpinalHDL/openocd_riscv.git";
+    rev = "058dfa50d625893bee9fecf8d604141911fac125";
+    sha256 = "sha256-UuX4Zfr9DiJx60nvBAv+9xCbWXExrk5KNSC5V5e4rsw=";
+    fetchSubmodules = true;
+    deepClone = true;
+    postFetch = ''
+      # See: https://github.com/NixOS/nixpkgs/issues/8567#issuecomment-1846499599
+      find "$out/" -type d -name '.git' | xargs rm -rf
+    '';
+  };
+
+  installPhase = ''
+    SKIP_SUBMODULE=1 ./bootstrap
+    ./configure --enable-ftdi --enable-dummy --prefix=$out
+    make -j $(nproc)
+    make install
+    mv $out/bin/openocd $out/bin/openocd-vexriscv
+  '';
+}

shell.nix

@@ -55,6 +55,7 @@ pkgs.mkShell {
       pkgs.pcre
 
       # VexRiscv OpenOCD
+      pkgs.openocd-vexriscv
       pkgs.openocd-riscv
       pkgs.gdb
 
@@ -78,7 +79,10 @@ pkgs.mkShell {
     # Prevents Perl warnings
     export LC_ALL="C.UTF-8";
     export VERILOG_ETHERNET_SRC="${pkgs.verilog-ethernet}"
+
+    # TODO: Get rid of custom OpenOCD build for sWCcTopologyTest
     export OPENOCD_DIST="${pkgs.openocd-riscv}"
+    export VEXOPENOCD_DIST="${pkgs.openocd-vexriscv}"
 
     # We use unstable features (floating point), we don't want to hear about it
     # every time we build.