Expand sbrk to allocate memory from two regions

pull/9944/head
Marcus Chang 2019-01-19 21:42:16 -08:00 committed by Deepika
parent 6dbc00dd8a
commit 7c0714132c
2 changed files with 85 additions and 3 deletions

View File

@ -16,7 +16,7 @@ M_CRASH_DATA_RAM_SIZE = 0x100;
/* Linker script to configure memory regions. */
MEMORY
{
{
FLASH (rx) : ORIGIN = MBED_APP_START, LENGTH = MBED_APP_SIZE
SRAM2 (rwx) : ORIGIN = 0x10000188, LENGTH = 32k - 0x188
SRAM1 (rwx) : ORIGIN = 0x20000000, LENGTH = 96k
@ -26,7 +26,7 @@ MEMORY
* with other linker script that defines memory regions FLASH and RAM.
* It references following symbols, which must be defined in code:
* Reset_Handler : Entry of reset handler
*
*
* It defines following symbols, which code can use without definition:
* __exidx_start
* __exidx_end
@ -93,7 +93,7 @@ SECTIONS
__etext = .;
_sidata = .;
.crash_data_ram :
{
. = ALIGN(8);
@ -173,6 +173,10 @@ SECTIONS
.stack_dummy (COPY):
{
*(.stack*)
. += (ORIGIN(SRAM2) + STACK_SIZE - .);
__mbed_sbrk_start_0 = .;
. += (ORIGIN(SRAM2) + LENGTH(SRAM2) - .);
__mbed_krbs_start_0 = .;
} > SRAM2
/* Set stack top to end of RAM, and stack limit move down by

View File

@ -0,0 +1,78 @@
/**
******************************************************************************
* @file l4_retarget.c
* @author MCD Application Team
* @brief CMSIS Cortex-M4 Core Peripheral Access Layer Source File for STM32L475xG
******************************************************************************
* @attention
*
* <h2><center>&copy; 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) && !defined(__ARMCC_VERSION))
#include <stdbool.h>
#include <errno.h>
#include "stm32l4xx.h"
extern uint32_t __mbed_sbrk_start;
extern uint32_t __mbed_krbs_start;
extern uint32_t __mbed_sbrk_start_0;
extern uint32_t __mbed_krbs_start_0;
/**
* The default implementation of _sbrk() (in platform/mbed_retarget.cpp) for GCC_ARM only supports one region.
* This implementation supports two regions by continuing the allocation to the second region after the first
* one is full.
* 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_0;
static bool once = true;
uint32_t heap_ind_old = heap_ind;
uint32_t heap_ind_new = heap_ind_old + incr;
/**
* If the new address is outside the first region, start allocating from the second region.
*/
if (once && (heap_ind_new >= (uint32_t)&__mbed_krbs_start_0)) {
once = false;
heap_ind_old = (uint32_t)&__mbed_sbrk_start;
heap_ind_new = heap_ind_old + incr;
/**
* If the new address is outside the second region, return out-of-memory.
*/
} else if (heap_ind_new >= (uint32_t)&__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*/