Support for FlexPRET platform

.github/workflows/ci.yml

@@ -55,6 +55,14 @@ jobs:
       compiler-ref: ${{ needs.fetch-lf.outputs.ref }}
     if: ${{ !github.event.pull_request.draft ||contains( github.event.pull_request.labels.*.name, 'zephyr') }}
 
+  lf-default-flexpret:
+    needs: [fetch-lf]
+    uses: lf-lang/lingua-franca/.github/workflows/c-flexpret-tests.yml@master
+    with:
+      runtime-ref: ${{ github.ref }}
+      compiler-ref: ${{ needs.fetch-lf.outputs.ref }}
+    if: ${{ !github.event.pull_request.draft ||contains( github.event.pull_request.labels.*.name, 'flexpret') }}
+
   lf-default:
     needs: [fetch-lf]
     uses: lf-lang/lingua-franca/.github/workflows/c-tests.yml@master

core/threaded/reactor_threaded.c

@@ -1072,8 +1072,13 @@ int lf_reactor_c_main(int argc, const char* argv[]) {
 
   LF_PRINT_DEBUG("Start time: " PRINTF_TIME "ns", start_time);
   struct timespec physical_time_timespec = {start_time / BILLION, start_time % BILLION};
+
+#ifdef NO_TTY
+  lf_print("---- Start execution ----");
+#else
   lf_print("---- Start execution at time %s---- plus %ld nanoseconds", ctime(&physical_time_timespec.tv_sec),
            physical_time_timespec.tv_nsec);
+#endif // NO_TTY
 
   // Create and initialize the environments for each enclave
   lf_create_environments();

core/utils/util.c

@@ -33,12 +33,26 @@ THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include "util.h"
 
+#if !defined(PLATFORM_FLEXPRET)
+#include <stdio.h>
+#else
+/**
+ * For FlexPRET specifically, a small footprint version of printf is used
+ */
+#include <printf/printf.h>
+/**
+ * Also, fflush and stdout are not provided so we just implement stubs
+ * 
+ */
+#define stdout (void *)(1)
+int fflush(void *stream) { (void) stream; return 0; }
+#endif // PLATFORM_FLEXPRET
+
 #ifndef STANDALONE_RTI
 #include "environment.h"
 #endif
 
 #include <errno.h>
-#include <stdio.h>
 #include <stdlib.h>
 #include <assert.h>
 #include <string.h> // Defines memcpy()

include/core/tracepoint.h

@@ -31,7 +31,9 @@
 #define TRACEPOINT_H
 
 #include "lf_types.h"
+#if !defined(PLATFORM_FLEXPRET)
 #include <stdio.h>
+#endif
 
 #ifdef FEDERATED
 #include "net_common.h"

low_level_platform/api/CMakeLists.txt

@@ -9,4 +9,7 @@ elseif(${CMAKE_SYSTEM_NAME} STREQUAL "Zephyr")
     target_compile_definitions(lf-low-level-platform-api INTERFACE PLATFORM_ZEPHYR)
 elseif(${CMAKE_SYSTEM_NAME} STREQUAL "Rp2040")
     target_compile_definitions(lf-low-level-platform-api INTERFACE PLATFORM_RP2040)
+elseif(${CMAKE_SYSTEM_NAME} STREQUAL "FlexPRET")
+    target_compile_definitions(lf-low-level-platform-api INTERFACE PLATFORM_FLEXPRET)
+    target_link_libraries(lf-low-level-platform-api INTERFACE fp-sdk)
 endif()

low_level_platform/api/low_level_platform.h

@@ -50,6 +50,8 @@ int lf_critical_section_exit(environment_t* env);
 #include "platform/lf_nrf52_support.h"
 #elif defined(PLATFORM_RP2040)
 #include "platform/lf_rp2040_support.h"
+#elif defined(PLATFORM_FLEXPRET)
+#include "platform/lf_flexpret_support.h"
 #elif defined(WIN32) || defined(_WIN32) || defined(__WIN32__) || defined(__NT__)
 // Windows platforms
 #include "platform/lf_windows_support.h"

low_level_platform/api/platform/lf_flexpret_support.h

@@ -0,0 +1,74 @@
+/* FlexPRET API support for the C target of Lingua Franca. */
+
+/*************
+Copyright (c) 2021, The University of California at Berkeley.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice,
+   this list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+***************/
+
+/**
+ * FlexPRET API support for the C target of Lingua Franca.
+ *
+ * @author{Magnus Mæhlum <[email protected]>}
+ */
+
+#ifndef LF_FLEXPRET_SUPPORT_H
+#define LF_FLEXPRET_SUPPORT_H
+
+#include <flexpret/flexpret.h>
+
+/**
+ * Like nRF52, for FlexPRET, each mutex will control an interrupt.
+ *
+ * The mutex holds the interrupt number.
+ * For example, a mutex might be defined for the GPIOTE peripheral interrupt number
+ *
+ * When initialized, the interrupt is inserted into a global linked list
+ * for disabling and enabling all interrupts during sleep functions.
+ * - All interrupts are disabled by default after initialization
+ * - Priority levels are restricted between (0-7)
+ *
+ */
+
+#include <inttypes.h> // Needed to define PRId64 and PRIu32
+#define PRINTF_TIME "%" PRId64
+#define PRINTF_MICROSTEP "%" PRIu32
+
+// For convenience, the following string can be inserted in a printf
+// format for printing both time and microstep as follows:
+//     printf("Tag is " PRINTF_TAG "\n", time_value, microstep);
+#define PRINTF_TAG "(%" PRId64 ", %" PRIu32 ")"
+
+#if !defined(LF_SINGLE_THREADED)
+typedef fp_lock_t lf_mutex_t;
+typedef fp_thread_t lf_thread_t;
+typedef fp_cond_t lf_cond_t;
+#endif
+
+// FlexPRET has no tty
+#define NO_TTY
+
+// Likewise, fprintf is used to print to `stderr`, but FlexPRET has no `stderr`
+// We instead redirect its output to normal printf
+#define fprintf(stream, fmt, ...) printf(fmt, ##__VA_ARGS__)
+#define vfprintf(fp, fmt, args) vprintf(fmt, args)
+
+#endif // LF_FLEXPRET_SUPPORT_H

low_level_platform/impl/CMakeLists.txt

@@ -39,8 +39,13 @@ elseif(${CMAKE_SYSTEM_NAME} STREQUAL "Rp2040")
         ${CMAKE_CURRENT_LIST_DIR}/src/lf_rp2040_support.c
         ${CMAKE_CURRENT_LIST_DIR}/src/lf_atomic_irq.c
     )
+elseif(${CMAKE_SYSTEM_NAME} STREQUAL "FlexPRET")
+    set(LF_LOW_LEVEL_PLATFORM_FILES
+        ${CMAKE_CURRENT_LIST_DIR}/src/lf_flexpret_support.c
+        ${CMAKE_CURRENT_LIST_DIR}/src/lf_atomic_irq.c
+    )
 else()
-    message(FATAL_ERROR "Your platform is not supported! The C target supports Linux, MacOS, Windows, Zephyr, Nrf52 and RP2040.")
+    message(FATAL_ERROR "Your platform is not supported! The C target supports FlexPRET, Linux, MacOS, Nrf52, RP2040, Windows, and Zephyr.")
 endif()
 
 list(APPEND LF_LOW_LEVEL_PLATFORM_FILES ${CMAKE_CURRENT_LIST_DIR}/src/lf_platform_util.c)
@@ -54,6 +59,32 @@ if(${CMAKE_SYSTEM_NAME} STREQUAL "Zephyr")
     zephyr_library_named(lf-low-level-platform-impl)
     zephyr_library_sources(${LF_LOW_LEVEL_PLATFORM_FILES})
     zephyr_library_link_libraries(kernel)
+elseif(${CMAKE_SYSTEM_NAME} STREQUAL "FlexPRET")
+    add_library(lf-low-level-platform-impl STATIC ${LF_LOW_LEVEL_PLATFORM_FILES})
+    target_link_libraries(lf-low-level-platform-impl PRIVATE fp-sdk)
+
+    if (DEFINED NUMBER_OF_WORKERS)
+        # Verify that FlexPRET has the number of requested workers
+        # That information is available in the SDK's hwconfig
+        include($ENV{FP_SDK_PATH}/flexpret/hwconfig.cmake)
+        if (NOT DEFINED THREADS)
+            message(FATAL_ERROR
+                "Missing FlexPRET hardware configuration; check that FlexPRET has \
+                been installed to the SDK."
+            )
+        endif()
+
+        math(EXPR FLEXPRET_AVAILABLE_WORKERS "${THREADS} - 1")
+
+        if (${NUMBER_OF_WORKERS} GREATER ${FLEXPRET_AVAILABLE_WORKERS})
+            message(FATAL_ERROR
+                "Number of requested workers (${NUMBER_OF_WORKERS}) is higher \
+                than FlexPRET's number of available workers \
+                (${FLEXPRET_AVAILABLE_WORKERS}). Note that FlexPRET uses \
+                hardware threads, not the usual software threads"
+            )
+        endif()
+    endif()
 else()
     add_library(lf-low-level-platform-impl STATIC ${LF_LOW_LEVEL_PLATFORM_FILES})
     # Link the platform to a threading library

low_level_platform/impl/src/lf_atomic_irq.c

@@ -1,4 +1,5 @@
-#if defined(PLATFORM_ARDUINO) || defined(PLATFORM_NRF52) || defined(PLATFORM_ZEPHYR) || defined(PLATFORM_RP2040)
+#if defined(PLATFORM_ARDUINO) || defined(PLATFORM_NRF52) || defined(PLATFORM_ZEPHYR) || defined(PLATFORM_RP2040) ||    \
+    defined(PLATFORM_FLEXPRET)
 /**
  * @author Erling Rennemo Jellum
  * @copyright (c) 2023