Enable building RP2350 bare-metal and PicoSDK firmwares in RISC-V mode, correct RISC-V CMSIS-DAP uploading

Author: maxgerhardt

builder/frameworks/_bare.py

@@ -22,7 +22,6 @@
 
 env.Append(
     ASFLAGS=[
-        "-mthumb",
     ],
     ASPPFLAGS=[
         "-x", "assembler-with-cpp",
@@ -33,7 +32,6 @@
         "-ffunction-sections",  # place each function in its own section
         "-fdata-sections",
         "-Wall",
-        "-mthumb",
         "-nostdlib"
     ],
 
@@ -49,7 +47,6 @@
     LINKFLAGS=[
         "-Os",
         "-Wl,--gc-sections,--relax",
-        "-mthumb",
         "--specs=nano.specs",
         "--specs=nosys.specs"
     ],
@@ -62,23 +59,28 @@
     mcu = env.BoardConfig().get("build.mcu", "")
     if mcu == "rp2350":
         more_flags = [
+            "-mcpu=%s" % env.BoardConfig().get("build.cpu"),
             "-march=armv8-m.main+fp+dsp",
+            "-mthumb",
             "-mfloat-abi=hard",
             "-mcmse",
         ]
-    if mcu == "rp2350-riscv":
+    elif mcu == "rp2040":
+        more_flags = [
+            "-mcpu=%s" % env.BoardConfig().get("build.cpu"),
+            "-mthumb",
+        ]
+    elif mcu == "rp2350-riscv":
         more_flags = [
+            # special value as supported by our RISC-V toolchain. No -mcpu.
             "-march=rv32imac_zicsr_zifencei_zba_zbb_zbs_zbkb",
             "-mabi=ilp32"
         ]
     env.Append(
-        ASFLAGS=[
-            "-mcpu=%s" % env.BoardConfig().get("build.cpu")
-        ] + more_flags,
-        CCFLAGS=[
-            "-mcpu=%s" % env.BoardConfig().get("build.cpu")
-        ] + more_flags,
-        LINKFLAGS=[
-            "-mcpu=%s" % env.BoardConfig().get("build.cpu")
-        ] + more_flags
+        ASFLAGS=more_flags,
+        CCFLAGS=more_flags,
+        LINKFLAGS=more_flags
     )
+
+    if mcu == "rp2350-riscv":
+        env.Append(LINKFLAGS=["-Wl,--no-warn-rwx-segments"])

builder/frameworks/picosdk.py

@@ -11,8 +11,9 @@
 FRAMEWORK_DIR = platform.get_package_dir("framework-picosdk")
 assert isdir(FRAMEWORK_DIR)
 
-mcu = "rp2350" if board.get('build.mcu') == "rp2350" else "rp2040"
-is_rp2350 = mcu == "rp2350"
+mcu = "rp2350" if "rp2350" in board.get('build.mcu') else "rp2040"
+is_rp2350 = mcu == "rp2350" # could be ARM or RISC-V
+is_riscv = board.get('build.mcu') == "rp2350-riscv"
 rp2_variant_dir = join(FRAMEWORK_DIR, "src", mcu)
 header = "%s.h" % board.get("build.variant")
 # try to find the board header in the common directory
@@ -58,11 +59,9 @@ def gen_config_autogen(target_base_dir, board_hdr):
     #CFLAGS=sorted(list(cflags - ccflags)),
     #CCFLAGS=sorted(list(ccflags)),
     CPPDEFINES=[
-        # BUG: defining PICO_RP2040 in any way will force compilation for 2040 only.
-        # FIX: add RP2350 only if board requested was 2350
-        ("PICO_RP2350" if board.get('build.mcu') == "rp2350" else "PICO_RP2040", 1),
-        ("PICO_RISCV", 0),
-        ("PICO_ARM", 1),
+        ("PICO_RP2350" if is_rp2350 else "PICO_RP2040", 1),
+        ("PICO_RISCV", int(is_riscv)),
+        ("PICO_ARM", int(not is_riscv)),
         ("PICO_CMSIS_DEVICE", "\"%s\"" % mcu.upper()),
         ("PICO_DEFAULT_FLASH_SIZE_BYTES", 2 * 1024 * 1024),
         # default SDK defines for on-hardware build
@@ -112,6 +111,7 @@ def gen_config_autogen(target_base_dir, board_hdr):
         join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_exception", "include"),
         join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_flash", "include"),
         join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_gpio", "include"),
+        join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_hazard3", "include"),
         join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_i2c", "include"),
         join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_interp", "include"),
         join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_irq", "include"),
@@ -120,6 +120,8 @@ def gen_config_autogen(target_base_dir, board_hdr):
         join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_pwm", "include"),
         join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_resets", "include"),
         join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_rcp", "include"),
+        join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_riscv", "include"),
+        join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_riscv_platform_timer", "include"),
         join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_rtc", "include"),
         join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_spi", "include"),
         join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_sync_spin_lock", "include"),
@@ -335,6 +337,11 @@ def configure_printf_impl():
 #     join("$BUILD_DIR", "PicoSDK"),
 #     join(FRAMEWORK_DIR, "src", "rp2_common", "cmsis", "stub", "CMSIS", "Device", "RP2040", "Source")
 # )
+if is_rp2350:
+    pad_checksum_arch = "-a riscv" if is_riscv else "-a arm"
+else:
+    # when calling into the RP2040 version of that script, it actually doesn't take a "-a" argument at all.
+    pad_checksum_arch = ""
 
 gen_boot2_cmd = env.Command(
     join("$BUILD_DIR", "boot2.S"),  # $TARGET
@@ -354,6 +361,7 @@ def configure_printf_impl():
         "-I", "$PROJECT_BUILD_DIR/$PIOENV/generated",
         "-I\"%s\"" % join(rp2_variant_dir, "pico_platform", "include"),
         "-I\"%s\"" % join(FRAMEWORK_DIR, "src", "rp2_common", "pico_platform_compiler", "include"),
+        "-I\"%s\"" % join(FRAMEWORK_DIR, "src", "rp2_common", "hardware_hazard3", "include"),
         "-I\"%s\"" % join(rp2_variant_dir, "hardware_regs", "include"),
         "-I\"%s\"" % join(FRAMEWORK_DIR, "src", "rp2_common", "pico_platform_common", "include"),
         "-I\"%s\"" % join(FRAMEWORK_DIR, "src", "rp2_common", "pico_platform_sections", "include"),
@@ -374,6 +382,7 @@ def configure_printf_impl():
         "$PYTHONEXE",
         join(FRAMEWORK_DIR, "src", mcu, "boot_stage2", "pad_checksum"),
         "-s 0xffffffff",
+        pad_checksum_arch,
         join("$BUILD_DIR", "boot2.bin"),
         join("$BUILD_DIR", "boot2.S"),
     ]), "Generating boot2 $BUILD_DIR/boot2.S")
@@ -468,11 +477,11 @@ def configure_printf_impl():
         src_filter
     )
 
-# Will be crt0_riscv.S for RISC-V builds..
+pico_crt0 = "crt0_riscv.S" if is_riscv else "crt0.S"
 env.BuildSources(
     join("$BUILD_DIR", "PicoSDKCRT0"),
     join(FRAMEWORK_DIR, "src", "rp2_common", "pico_crt0"),
-    "-<*> +<crt0.S>"
+    "-<*> +<%s>" % pico_crt0
 )
 
 default_common_components = [

builder/main.py

@@ -166,7 +166,7 @@ def BeforeUpload(target, source, env):  # pylint: disable=W0613,W0621
         env.TouchSerialPort("$UPLOAD_PORT", 1200)
         # delay a tiny bit in any case
         time.sleep(0.2)
-        max_wait_s = 3.0
+        max_wait_s = 5.0
         while max_wait_s > 0:
             if get_num_rpxxxx_devs(picotool_path) > num_before:
                 print("Device rebooted into BOOTSEL mode successfully.")

examples/picosdk-blink/platformio.ini

@@ -21,4 +21,9 @@ board = pico
 board = rpipico2
 ; explicitly set the board header for all pin definitions if not automatically detected
 ; see <home folder>/.platformio/packages/framework-arduinopico/pico-sdk/src/boards/include/boards
-board_build.picosdk.board_header = pimoroni_tiny2350.h
+board_build.picosdk.board_header = pimoroni_plasma2350.h
+
+[env:pico2-riscv]
+board = rpipico2
+board_build.mcu = rp2350-riscv
+board_build.picosdk.board_header = pimoroni_plasma2350.h

platform.json

@@ -41,6 +41,12 @@
       "owner": "earlephilhower",
       "version": "https://github.com/maxgerhardt/toolchain-dummy/archive/refs/heads/main.zip"
     },
+    "toolchain-riscv-rp2350": {
+      "type": "toolchain",
+      "optional": true,
+      "owner": "platformio",
+      "version": "https://github.com/maxgerhardt/toolchain-dummy/archive/refs/heads/main-riscv.zip"
+    },
     "framework-arduino-mbed": {
       "type": "framework",
       "optional": true,

platform.py

@@ -23,6 +23,22 @@ class RaspberrypiPlatform(PlatformBase):
     def is_embedded(self):
         return True
 
+    picosdk_toolchain_riscv = {
+        # Windows
+        "windows_amd64": "https://github.com/maxgerhardt/toolchain-riscv-rp2350/releases/download/15.1.0/pio-riscv-toolchain-15-x64-win.zip",
+        #"windows_x86": ""
+        # No Windows x86, ARM64 or ARM32 builds.
+        # Linux
+        "linux_x86_64": "https://github.com/maxgerhardt/toolchain-riscv-rp2350/releases/download/15.1.0/toolchain-riscv-rp2350-linux_x86_64-1.150100.250822.tar.gz",
+        #"linux_i686": "",
+        "linux_aarch64": "https://github.com/maxgerhardt/toolchain-riscv-rp2350/releases/download/15.1.0/toolchain-riscv-rp2350-linux_aarch64-1.150100.250822.tar.gz",
+        #"linux_armv7l": "",
+        #"linux_armv6l": "",
+        # Mac (Intel and ARM are the separate)
+        "darwin_x86_64": "https://github.com/maxgerhardt/toolchain-riscv-rp2350/releases/download/15.1.0/toolchain-riscv-rp2350-darwin_x86_64-1.150100.250822.tar.gz",
+        "darwin_arm64": "https://github.com/maxgerhardt/toolchain-riscv-rp2350/releases/download/15.1.0/toolchain-riscv-rp2350-darwin_arm64-1.150100.250822.tar.gz"
+    }
+
     earle_toolchain_arm = {
         # Windows
         "windows_amd64": "https://github.com/earlephilhower/pico-quick-toolchain/releases/download/4.1.0/x86_64-w64-mingw32.arm-none-eabi-1aec55e.250530.zip",
@@ -87,11 +103,15 @@ def is_embedded(self):
         "darwin_arm64": "https://github.com/earlephilhower/pico-quick-toolchain/releases/download/4.1.0/aarch64-apple-darwin20.4.picotool-c56c005.250530.tar.gz"
     }
 
+    last_board_is_riscv = False
+
     def configure_default_packages(self, variables, targets):
         #print("System type: %s" % (util.get_systype()))
         # configure arduino core package.
         # select the right one based on the build.core, disable other one.
         board = variables.get("board")
+        # workaround: remember this for upload logic
+        self.last_board_is_riscv = variables.get("board_build.mcu", "").endswith("-riscv")
         board_config = self.board_config(board)
         chip = variables.get("board_build.mcu", board_config.get("build.mcu"))
         build_core = variables.get(
@@ -128,7 +148,13 @@ def configure_default_packages(self, variables, targets):
                 sys.stderr.write(
                     "Error! Unknown build.core value '%s'. Don't know which Arduino core package to use." % build_core)
                 env.Exit(1)
-
+        else:
+            # this is a pico-sdk or baremetal project. if it's for a rp2350-riscv, we need the RISC-V toolchain.
+            if chip == "rp2350-riscv":
+                self.packages["toolchain-riscv-rp2350"]["optional"] = False
+                self.packages["toolchain-riscv-rp2350"]["version"] = RaspberrypiPlatform.picosdk_toolchain_riscv[sys_type]
+                self.packages.pop("toolchain-gccarmnoneeabi", None)
+            # rest is okay for ARM-based RP2040/RP2350.
         # if we want to build a filesystem, we need the tools.
         if "buildfs" in targets:
             self.packages["tool-mklittlefs-rp2040-earlephilhower"]["optional"] = False
@@ -208,6 +234,8 @@ def _add_default_debug_tools(self, board):
                 }
             else:
                 openocd_target = debug.get("openocd_target")
+                if self.last_board_is_riscv:
+                    openocd_target = "rp2350-riscv.cfg"
                 assert openocd_target, ("Missing target configuration for %s" %
                                         board.id)
                 debug["tools"][link] = {