amiro-blt / Target / Source / ARMCM3_STM32 / GCC / cstart.c @ 31d314a9
History | View | Annotate | Download (3.987 KB)
| 1 | 69661903 | Thomas Schöpping | /************************************************************************************//** |
|---|---|---|---|
| 2 | * \file Source\ARMCM3_STM32\GCC\cstart.c
|
||
| 3 | * \brief Bootloader C startup source file.
|
||
| 4 | * \ingroup Target_ARMCM3_STM32
|
||
| 5 | * \internal
|
||
| 6 | *----------------------------------------------------------------------------------------
|
||
| 7 | * C O P Y R I G H T
|
||
| 8 | *----------------------------------------------------------------------------------------
|
||
| 9 | * Copyright (c) 2011 by Feaser http://www.feaser.com All rights reserved
|
||
| 10 | *
|
||
| 11 | *----------------------------------------------------------------------------------------
|
||
| 12 | * L I C E N S E
|
||
| 13 | *----------------------------------------------------------------------------------------
|
||
| 14 | * This file is part of OpenBLT. OpenBLT is free software: you can redistribute it and/or
|
||
| 15 | * modify it under the terms of the GNU General Public License as published by the Free
|
||
| 16 | * Software Foundation, either version 3 of the License, or (at your option) any later
|
||
| 17 | * version.
|
||
| 18 | *
|
||
| 19 | * OpenBLT is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
|
||
| 20 | * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
|
||
| 21 | * PURPOSE. See the GNU General Public License for more details.
|
||
| 22 | *
|
||
| 23 | * You should have received a copy of the GNU General Public License along with OpenBLT.
|
||
| 24 | * If not, see <http://www.gnu.org/licenses/>.
|
||
| 25 | *
|
||
| 26 | * A special exception to the GPL is included to allow you to distribute a combined work
|
||
| 27 | * that includes OpenBLT without being obliged to provide the source code for any
|
||
| 28 | * proprietary components. The exception text is included at the bottom of the license
|
||
| 29 | * file <license.html>.
|
||
| 30 | *
|
||
| 31 | * \endinternal
|
||
| 32 | ****************************************************************************************/
|
||
| 33 | |||
| 34 | /****************************************************************************************
|
||
| 35 | * Include files
|
||
| 36 | ****************************************************************************************/
|
||
| 37 | #include "boot.h" /* bootloader generic header */ |
||
| 38 | |||
| 39 | |||
| 40 | /****************************************************************************************
|
||
| 41 | * External function protoypes
|
||
| 42 | ****************************************************************************************/
|
||
| 43 | extern int main(void); |
||
| 44 | |||
| 45 | |||
| 46 | /****************************************************************************************
|
||
| 47 | * External data declarations
|
||
| 48 | ****************************************************************************************/
|
||
| 49 | /* these externals are declared by the linker */
|
||
| 50 | extern blt_int32u _etext;
|
||
| 51 | extern blt_int32u _data;
|
||
| 52 | extern blt_int32u _edata;
|
||
| 53 | extern blt_int32u _bss;
|
||
| 54 | extern blt_int32u _ebss;
|
||
| 55 | extern blt_int32u _estack;
|
||
| 56 | |||
| 57 | |||
| 58 | /************************************************************************************//** |
||
| 59 | ** \brief Reset interrupt service routine. Configures the stack, initializes
|
||
| 60 | ** RAM and jumps to function main.
|
||
| 61 | ** \return none.
|
||
| 62 | **
|
||
| 63 | ****************************************************************************************/
|
||
| 64 | void reset_handler(void) |
||
| 65 | {
|
||
| 66 | blt_int32u *pSrc, *pDest; |
||
| 67 | |||
| 68 | /* disable interrupts first */
|
||
| 69 | __asm(" cpsid i");
|
||
| 70 | /* copy the data segment initializers from flash to SRAM */
|
||
| 71 | pSrc = &_etext; |
||
| 72 | for(pDest = &_data; pDest < &_edata; )
|
||
| 73 | {
|
||
| 74 | *pDest++ = *pSrc++; |
||
| 75 | } |
||
| 76 | /* zero fill the bss segment. this is done with inline assembly since this will
|
||
| 77 | * clear the value of pDest if it is not kept in a register.
|
||
| 78 | */
|
||
| 79 | __asm(" ldr r0, =_bss\n"
|
||
| 80 | " ldr r1, =_ebss\n"
|
||
| 81 | " mov r2, #0\n"
|
||
| 82 | " .thumb_func\n"
|
||
| 83 | "zero_loop:\n"
|
||
| 84 | " cmp r0, r1\n"
|
||
| 85 | " it lt\n"
|
||
| 86 | " strlt r2, [r0], #4\n"
|
||
| 87 | " blt zero_loop");
|
||
| 88 | /* start the software application by calling its entry point */
|
||
| 89 | main(); |
||
| 90 | } /*** end of reset_handler ***/
|
||
| 91 | |||
| 92 | |||
| 93 | /************************************ end of cstart.c **********************************/ |