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Dependents: STM32_F103-C8T6basecanblink_led
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Diff: targets/TARGET_STM/TARGET_STM32L4/l4_retarget.c
- Revision:
- 183:a56a73fd2a6f
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/TARGET_STM/TARGET_STM32L4/l4_retarget.c Tue Mar 20 16:56:18 2018 +0000 @@ -0,0 +1,66 @@ +/** + ****************************************************************************** + * @file l4_retarget.c + * @author MCD Application Team + * @brief CMSIS Cortex-M4 Core Peripheral Access Layer Source File for STM32L475xG + ****************************************************************************** + * @attention + * + * <h2><center>© COPYRIGHT(c) 2018 STMicroelectronics</center></h2> + * + * 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. + * 3. Neither the name of STMicroelectronics nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * 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. + * + ****************************************************************************** + */ +#if (defined(TWO_RAM_REGIONS) && defined(__GNUC__) && !defined(__CC_ARM)) +#include <errno.h> +#include "stm32l4xx.h" +extern uint32_t __mbed_sbrk_start; +extern uint32_t __mbed_krbs_start; + +#define STM32L4_HEAP_ALIGN 32 +#define STM32L4_ALIGN_UP(X, ALIGN) (((X) + (ALIGN) - 1) & ~((ALIGN) - 1)) +/** + * The default implementation of _sbrk() (in platform/mbed_retarget.cpp) for GCC_ARM requires one-region model (heap and + * stack share one region), which doesn't fit two-region model (heap and stack are two distinct regions), for example, + * STM32L475xG locates heap on SRAM1 and stack on SRAM2. + * Define __wrap__sbrk() to override the default _sbrk(). It is expected to get called through gcc + * hooking mechanism ('-Wl,--wrap,_sbrk') or in _sbrk(). + */ +void *__wrap__sbrk(int incr) +{ + static uint32_t heap_ind = (uint32_t) &__mbed_sbrk_start; + uint32_t heap_ind_old = STM32L4_ALIGN_UP(heap_ind, STM32L4_HEAP_ALIGN); + uint32_t heap_ind_new = STM32L4_ALIGN_UP(heap_ind_old + incr, STM32L4_HEAP_ALIGN); + + if (heap_ind_new > &__mbed_krbs_start) { + errno = ENOMEM; + return (void *) -1; + } + + heap_ind = heap_ind_new; + + return (void *) heap_ind_old; +} +#endif /* GCC_ARM toolchain && TWO_RAM_REGIONS*/ +