o Actually working implementation of context switching.

It is important to remember to update the stack to the task descriptor on every switch!

2 files changed, 107 insertions, 0 deletions

diff --git a/apps/cpp1/CMakeLists.txt b/apps/cpp1/CMakeLists.txt
new file mode 100644
index 0000000..2580535
--- /dev/null
+++ b/apps/cpp1/CMakeLists.txt
@@ -0,0 +1,19 @@
+add_executable(cpp1.elf cpp1.cpp
+        ${STM32F10X_STDPERIPH_LIB}/Libraries/CMSIS/CM3/CoreSupport/core_cm3.c
+        ${STM32F10X_STDPERIPH_LIB}/Libraries/CMSIS/CM3/DeviceSupport/ST/STM32F10x/system_stm32f10x.c
+        ${STM32F10X_STDPERIPH_LIB}/Libraries/STM32F10x_StdPeriph_Driver/src/misc.c
+        ${STM32F10X_STDPERIPH_LIB}/Libraries/STM32F10x_StdPeriph_Driver/src/stm32f10x_rcc.c
+        ${STM32F10X_STDPERIPH_LIB}/Libraries/STM32F10x_StdPeriph_Driver/src/stm32f10x_spi.c
+        ${STM32F10X_STDPERIPH_LIB}/Libraries/STM32F10x_StdPeriph_Driver/src/stm32f10x_gpio.c
+        ${STM32F10X_STDPERIPH_LIB}/Libraries/STM32F10x_StdPeriph_Driver/src/stm32f10x_dma.c
+        $<TARGET_OBJECTS:playground>
+        )
+
+target_include_directories(cpp1.elf PUBLIC
+        $<TARGET_PROPERTY:playground,INTERFACE_INCLUDE_DIRECTORIES>
+        )
+target_compile_definitions(cpp1.elf PUBLIC ${STM32F10X_STDPERIPH_DEFINES})
+target_link_libraries(cpp1.elf tinyprintf)
+
+set_target_properties(cpp1.elf PROPERTIES LINK_FLAGS "-nostartfiles -T${CMAKE_SOURCE_DIR}/cmake/stm32.ld")
+add_extra_commands(cpp1.elf)
diff --git a/apps/cpp1/cpp1.cpp b/apps/cpp1/cpp1.cpp
new file mode 100644
index 0000000..5cea157
--- /dev/null
+++ b/apps/cpp1/cpp1.cpp
@@ -0,0 +1,88 @@
+#include <stdint.h>
+#include <stm32f10x.h>
+
+#include "debug.h"
+#include "tinyprintf.h"
+#include "playground.h"
+
+extern "C"
+__attribute__((naked, used))
+void HardFault_Handler_C(uint32_t *hardfault_args) {
+    dbg_printf("r0  = 0x%08lx (%lu)\n", hardfault_args[0], hardfault_args[0]);
+    dbg_printf("r1  = 0x%08lx (%lu)\n", hardfault_args[1], hardfault_args[1]);
+    dbg_printf("r2  = 0x%08lx (%lu)\n", hardfault_args[2], hardfault_args[2]);
+    dbg_printf("r3  = 0x%08lx (%lu)\n", hardfault_args[3], hardfault_args[3]);
+    dbg_printf("r12 = 0x%08lx (%lu)\n", hardfault_args[4], hardfault_args[4]);
+    dbg_printf("lr  = 0x%08lx (%lu)\n", hardfault_args[5], hardfault_args[5]);
+    dbg_printf("pc  = 0x%08lx (%lu)\n", hardfault_args[6], hardfault_args[6]);
+    dbg_printf("psr = 0x%08lx (%lu)\n", hardfault_args[7], hardfault_args[7]);
+    dbg_printf("\n");
+
+    halt();
+}
+
+volatile bool run = true;
+
+class StaticMyClass {
+public:
+    StaticMyClass(int value) : value(value) {
+        dbg_printf("StaticMyClass::StaticMyClass(%d)\n", value);
+    }
+
+    // Destructors are not supported for classes that are globally allocated.
+//    ~StaticMyClass() {
+//    }
+
+    int value;
+};
+
+class ConstStaticMyClass {
+public:
+    ConstStaticMyClass(int value) : value(value) {
+        dbg_printf("ConstStaticMyClass::ConstStaticMyClass(%d)\n", value);
+    }
+
+    int value;
+};
+
+class MyClass {
+public:
+    MyClass(int value) : value(value) {
+        dbg_printf("MyClass::MyClass(%d)\n", value);
+    }
+
+    ~MyClass() {
+        dbg_printf("MyClass::~MyClass\n");
+    }
+
+    int value;
+};
+
+StaticMyClass staticInstance(1337);
+static const ConstStaticMyClass constStaticInstance(9876);
+
+/*
+ * When we get there the stack pointer is set
+ */
+int main() {
+    SystemInit();
+
+    init_printf(nullptr, dbg_putc);
+
+    dbg_printf("C++ Test #1\n");
+
+    dbg_printf("staticInstance.value=%d\n", staticInstance.value);
+    dbg_printf("constStaticInstance.value=%d\n", constStaticInstance.value);
+
+    {
+        MyClass instance2(1234);
+        dbg_printf("instance2.value=%d\n", instance2.value);
+    }
+
+    dbg_printf("Sleeping..\n");
+    while (run) {
+        __NOP();
+    }
+
+    return 0;
+}