2018-09-12 20:00:13 -04:00

99 lines
3.2 KiB
C

/**************************************************************************//**
* @file boot.c
* @brief Functions for booting another application
* @author Silicon Labs
* @version 1.03
******************************************************************************
* @section License
* <b>(C) Copyright 2014 Silicon Labs, http://www.silabs.com</b>
*******************************************************************************
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*
* DISCLAIMER OF WARRANTY/LIMITATION OF REMEDIES: Silicon Labs has no
* obligation to support this Software. Silicon Labs is providing the
* Software "AS IS", with no express or implied warranties of any kind,
* including, but not limited to, any implied warranties of merchantability
* or fitness for any particular purpose or warranties against infringement
* of any proprietary rights of a third party.
*
* Silicon Labs will not be liable for any consequential, incidental, or
* special damages, or any other relief, or for any claim by any third party,
* arising from your use of this Software.
*
******************************************************************************/
#include "em_device.h"
#include "em_gpio.h"
#include "em_cmu.h"
#include "app.h"
/******************************************************************************
* This function sets up the Cortex-M3 with a new SP and PC.
*****************************************************************************/
#if defined ( __CC_ARM )
__asm void BOOT_jump(uint32_t sp, uint32_t pc)
{
/* Set new MSP, PSP based on SP (r0)*/
msr msp, r0
msr psp, r0
/* Jump to PC (r1)*/
bx r1
}
#else
void __attribute__((optimize("O0"))) BOOT_jump(uint32_t sp, uint32_t pc)
{
(void) sp;
(void) pc;
/* Set new MSP, PSP based on SP (r0)*/
__asm("msr msp, r0");
__asm("msr psp, r0");
/* Jump to PC (r1)*/
__asm("mov pc, r1");
}
#endif
/* Resets any peripherals that have been in use by
* the bootloader before booting the appliation */
static void resetPeripherals(void)
{
}
/******************************************************************************
* Boots the firmware. This function will activate the vector table
* of the firmware application and set the PC and SP from this table.
*****************************************************************************/
void __attribute__((optimize("O0"))) BOOT_boot(void)
{
uint32_t pc, sp;
uint32_t *bootAddress = (uint32_t *)(JUMP_LOC);
resetPeripherals();
/* Set new vector table */
SCB->VTOR = (uint32_t)bootAddress;
/* Read new SP and PC from vector table */
sp = bootAddress[0];
pc = bootAddress[1];
/* Do a jump by loading the PC and SP into the CPU registers */
BOOT_jump(sp, pc);
}