git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@2877 35acf78f-673a-0410-8e92-d51de3d6d3f4

os/ports/GCC/ARMCMx/crt0.c

@@ -0,0 +1,275 @@
+/*
+    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010 Giovanni Di Sirio.
+
+    This file is part of ChibiOS/RT.
+
+    ChibiOS/RT is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    ChibiOS/RT is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+/**
+ * @file    ARMCMx/crt0.c
+ * @brief   Generic ARMvx-M (Cortex-M0/M1/M3/M4) startup file for ChibiOS/RT.
+ *
+ * @addtogroup ARMCMx_CORE
+ * @{
+ */
+
+#include "chtypes.h"
+
+/**
+ * @brief   Control special register initialization value.
+ * @details The system is setup to run in privileged mode using the PSP
+ *          stack (dual stack mode).
+ */
+#if !defined(CRT0_CONTROL_INIT) || defined(__DOXYGEN__)
+#define CRT0_CONTROL_INIT       0x00000002
+#endif
+
+/**
+ * @brief   DATA segment initialization switch.
+ */
+#if !defined(CRT0_INIT_DATA) || defined(__DOXYGEN__)
+#define CRT0_INIT_DATA          TRUE
+#endif
+
+/**
+ * @brief   BSS segment initialization switch.
+ */
+#if !defined(CRT0_INIT_BSS) || defined(__DOXYGEN__)
+#define CRT0_INIT_BSS           TRUE
+#endif
+
+/**
+ * @brief   Constructors invocation switch.
+ */
+#if !defined(CRT0_CALL_CONSTRUCTORS) || defined(__DOXYGEN__)
+#define CRT0_CALL_CONSTRUCTORS  TRUE
+#endif
+
+/**
+ * @brief   Destructors invocation switch.
+ */
+#if !defined(CRT0_CALL_DESTRUCTORS) || defined(__DOXYGEN__)
+#define CRT0_CALL_DESTRUCTORS   TRUE
+#endif
+
+#define SYMVAL(sym) (uint32_t)(((uint8_t *)&(sym)) - ((uint8_t *)0))
+
+/**
+ * @brief   Ram end.
+ * @details This symbol must be exported by the linker script and represents
+ *          the location after the last RAM location.
+ */
+extern uint8_t __ram_end__;
+
+/**
+ * @brief   Main stack size.
+ * @details This symbol must be exported by the linker script and represents
+ *          the main stack size.
+ * @note    The main stack is the stack where interrupts and exceptions are
+ *          processed.
+ */
+extern uint8_t __main_stack_size__;
+
+/**
+ * @brief   Process stack size.
+ * @details This symbol must be exported by the linker script and represents
+ *          the process stack size.
+ * @note    The process stack is the stack used by the @p main() function.
+ */
+extern uint8_t __process_stack_size__;
+
+/**
+ * @brief   ROM image of the data segment start.
+ * @pre     The symbol must be aligned to a 32 bits boundary.
+ */
+extern uint32_t _textdata;
+
+/**
+ * @brief   Data segment start.
+ * @pre     The symbol must be aligned to a 32 bits boundary.
+ */
+extern uint32_t _data;
+
+/**
+ * @brief   Data segment end.
+ * @pre     The symbol must be aligned to a 32 bits boundary.
+ */
+extern uint32_t _edata;
+
+/**
+ * @brief   BSS segment start.
+ * @pre     The symbol must be aligned to a 32 bits boundary.
+ */
+extern uint32_t _bss_start;
+
+/**
+ * @brief   BSS segment end.
+ * @pre     The symbol must be aligned to a 32 bits boundary.
+ */
+extern uint32_t _bss_end;
+
+/**
+ * @brief   Constructors table start.
+ * @pre     The symbol must be aligned to a 32 bits boundary.
+ */
+extern void __init_array_start(void);
+
+/**
+ * @brief   Constructors table end.
+ * @pre     The symbol must be aligned to a 32 bits boundary.
+ */
+extern void __init_array_end(void);
+
+/**
+ * @brief   Destructors table start.
+ * @pre     The symbol must be aligned to a 32 bits boundary.
+ */
+extern void __fini_array_start(void);
+
+/**
+ * @brief   Destructors table end.
+ * @pre     The symbol must be aligned to a 32 bits boundary.
+ */
+extern void __fini_array_end(void);
+
+/**
+ * @brief   Application @p main() function.
+ *
+ * @param[in] argc      Number of arguments, always zero.
+ * @param[in] argv      Pointer to an array of arguments, always @p NULL.
+ */
+extern void main(int argc, char **argv);
+
+/**
+ * @brief   Default initialization hook 0.
+ * @details This hook is invoked immediately after the stack initialization
+ *          and before the DATA and BSS segments initialization. The
+ *          default behavior is to do nothing.
+ * @note    This function is a weak symbol.
+ */
+#if !defined(__DOXYGEN__)
+__attribute__((weak))
+#endif
+void hwinit0(void) {}
+
+/**
+ * @brief   Default initialization hook 1.
+ * @details This hook is invoked immediately after the DATA and BSS segments
+ *          initialization and before entering the @p main() function. The
+ *          default behavior is to do nothing.
+ * @note    This function is a weak symbol.
+ */
+#if !defined(__DOXYGEN__)
+__attribute__((weak))
+#endif
+void hwinit1(void) {}
+
+/**
+ * @brief   Default @p main() function exit handler.
+ * @details This handler is invoked or the @p main() function exit. The
+ *          default behavior is to enter an infinite loop.
+ * @note    This function is a weak symbol.
+ */
+#if !defined(__DOXYGEN__)
+__attribute__((weak, naked))
+#endif
+void _main_exit_handler(void) {
+  while (1)
+    ;
+}
+
+/**
+ * @brief   Reset vector.
+ */
+#if !defined(__DOXYGEN__)
+__attribute__((naked))
+#endif
+void ResetHandler(void) {
+  uint32_t sz, ctl;
+
+  /* Process Stack initialization, it is allocated below the main stack. The
+     main stack is assumed to be allocated starting from @p __ram_end__
+     extending downward.*/
+  asm volatile ("cpsid   i");
+  sz = SYMVAL(__ram_end__) - SYMVAL(__main_stack_size__);
+  asm volatile ("msr     PSP, %0" : : "r" (sz));
+
+  ctl = CRT0_CONTROL_INIT;
+  asm volatile ("msr     CONTROL, %0" : : "r" (ctl));
+  asm volatile ("isb");
+
+  /* Initialization hook 0 invocation.*/
+  hwinit0();
+
+#if CRT0_INIT_DATA
+  /* DATA segment initialization.*/
+  {
+    uint32_t *tp, *dp;
+
+    tp = &_textdata;
+    dp = &_data;
+    while (dp < &_edata)
+      *dp++ = *tp++;
+  }
+#endif
+
+#if CRT0_INIT_BSS
+  /* BSS segment initialization.*/
+  {
+    uint32_t *bp;
+
+    bp = &_bss_start;
+    while (bp < &_bss_end)
+      *bp++ = 0;
+  }
+#endif
+
+  /* Initialization hook 1 invocation.*/
+  hwinit1();
+
+#if CRT0_CALL_CONSTRUCTORS
+  /* Constructors invocation.*/
+  {
+    void (*dpp)(void);
+
+    dpp = &__init_array_start;
+    while (dpp < &__init_array_end) {
+      (*dpp)();
+      dpp++;
+    }
+  }
+#endif
+
+  /* Invoking application main() function.*/
+  main(0, 0);
+
+#if CRT0_CALL_DESTRUCTORS
+  /* Destructors invocation.*/
+  {
+    void (*dpp)(void);
+
+    dpp = &__fini_array_start;
+    while (dpp < &__fini_array_end) {
+      (*dpp)();
+      dpp++;
+    }
+  }
+#endif
+
+  /* Invoking the main() exit handler.*/
+  asm volatile ("b       _main_exit_handler");
+}
+
+/** @} */