riscv-openocd/contrib/loaders/flash/cc26xx/startup.c

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/******************************************************************************
*
* Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 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.
*
* Neither the name of Texas Instruments Incorporated 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
* OWNER 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.
*
******************************************************************************/
#include <stdint.h>
/******************************************************************************
*
* The entry point for the application startup code.
*
******************************************************************************/
extern int main(void);
/******************************************************************************
*
* Reserve space for the system stack.
*
******************************************************************************/
__attribute__ ((section(".stack")))
static uint32_t stack[100];
const uint32_t stack_pntr = (uint32_t)stack + sizeof(stack);
/******************************************************************************
*
* The following are constructs created by the linker indicating where the
* the "bss" and "ebss" segments reside in memory.
*
******************************************************************************/
extern uint32_t _bss;
extern uint32_t _ebss;
/******************************************************************************
*
* This is the entry point that handles setting the stack within the allowed
* workspace, initializing the .bss segment, and then jumping to main.
*
******************************************************************************/
__attribute__ ((section(".entry")))
void entry(void)
{
/* Workaround for ITT instructions. */
__asm(" NOP");
__asm(" NOP");
__asm(" NOP");
__asm(" NOP");
/* Initialize stack pointer */
__asm(" ldr sp, =stack_pntr");
/* Zero fill the bss segment. */
__asm(" ldr r0, =_bss\n"
" ldr r1, =_ebss\n"
" mov r2, #0\n"
" .thumb_func\n"
" zero_loop:\n"
" cmp r0, r1\n"
" it lt\n"
" strlt r2, [r0], #4\n"
" blt zero_loop");
/* Call the application's entry point. */
main();
/* If we ever return, enter an infinite loop */
while (1)
;
}