98 lines
3.5 KiB
C
98 lines
3.5 KiB
C
/******************************************************************************
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*
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* Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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*
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* Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the
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* distribution.
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*
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* Neither the name of Texas Instruments Incorporated nor the names of
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* its contributors may be used to endorse or promote products derived
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* from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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******************************************************************************/
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#include <stdint.h>
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/******************************************************************************
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*
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* The entry point for the application startup code.
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*
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******************************************************************************/
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extern int main(void);
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/******************************************************************************
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*
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* Reserve space for the system stack.
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*
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******************************************************************************/
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__attribute__ ((section(".stack")))
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static uint32_t stack[100];
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const uint32_t stack_pntr = (uint32_t)stack + sizeof(stack);
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/******************************************************************************
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*
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* The following are constructs created by the linker indicating where the
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* the "bss" and "ebss" segments reside in memory.
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*
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******************************************************************************/
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extern uint32_t _bss;
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extern uint32_t _ebss;
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/******************************************************************************
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*
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* This is the entry point that handles setting the stack within the allowed
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* workspace, initializing the .bss segment, and then jumping to main.
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*
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******************************************************************************/
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__attribute__ ((section(".entry")))
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void entry(void)
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{
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/* Workaround for ITT instructions. */
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__asm(" NOP");
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__asm(" NOP");
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__asm(" NOP");
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__asm(" NOP");
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/* Initialize stack pointer */
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__asm(" ldr sp, =stack_pntr");
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/* Zero fill the bss segment. */
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__asm(" ldr r0, =_bss\n"
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" ldr r1, =_ebss\n"
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" mov r2, #0\n"
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" .thumb_func\n"
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" zero_loop:\n"
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" cmp r0, r1\n"
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" it lt\n"
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" strlt r2, [r0], #4\n"
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" blt zero_loop");
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/* Call the application's entry point. */
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main();
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/* If we ever return, enter an infinite loop */
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while (1)
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;
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}
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