boot_stub.S

/* {{{1 License
    FreeRTOS V8.2.0 - Copyright (C) 2015 Real Time Engineers Ltd.
    All rights reserved

    VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.

    This file is part of the FreeRTOS distribution.

    FreeRTOS is free software; you can redistribute it and/or modify it under
    the terms of the GNU General Public License (version 2) as published by the
    Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception.

	***************************************************************************
    >>!   NOTE: The modification to the GPL is included to allow you to     !<<
    >>!   distribute a combined work that includes FreeRTOS without being   !<<
    >>!   obliged to provide the source code for proprietary components     !<<
    >>!   outside of the FreeRTOS kernel.                                   !<<
	***************************************************************************

    FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
    WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
    FOR A PARTICULAR PURPOSE.  Full license text is available on the following
    link: http://www.freertos.org/a00114.html

    ***************************************************************************
     *                                                                       *
     *    FreeRTOS provides completely free yet professionally developed,    *
     *    robust, strictly quality controlled, supported, and cross          *
     *    platform software that is more than just the market leader, it     *
     *    is the industry's de facto standard.                               *
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     *    Help yourself get started quickly while simultaneously helping     *
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     *    tutorial book, reference manual, or both:                          *
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    ***************************************************************************

    http://www.FreeRTOS.org/FAQHelp.html - Having a problem?  Start by reading
	the FAQ page "My application does not run, what could be wrong?".  Have you
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    http://www.SafeRTOS.com - High Integrity Systems also provide a safety
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    1 tab == 4 spaces!

    Author:
      Dr. Johann Pfefferl <johann.pfefferl@siemens.com>
      Siemens AG
}}} */

.arm
.extern inmate_main

.set SYS_MODE,	0x1f
.set SVC_MODE,	0x13
.set IRQ_MODE,	0x12
.set MODE_MASK,	0x1f

.section ".boot", "ax"
.global vectors
.align 5
vectors:
	b	vector_reset
	b	vector_undef
	b	vector_svc
	b	vector_pabt
	b	vector_dabt
	b	vector_unused
	b	vector_irq
	b	vector_fiq

.macro vector, name
	.weak vector_\name
	vector_\name:
	b	.
.endm
	vector undef
	vector svc
	vector pabt
	vector dabt
	vector unused
	vector irq
	vector fiq

vector_reset:
	ldr	r0, =vectors
	mcr	p15, 0, r0, c12, c0, 0	@ VBAR

	bl	_install_irq_stack
	ldr	sp, =stack_top /* setup stack for application */

	b	inmate_main

_install_irq_stack:
      mrs     r0, cpsr          /* Switch to IRQ mode */
      and     r1, r0, #MODE_MASK/* Save old mode in r1 */
      bic     r0, r0, r1        /* Clear mode bits */
      orr     r0, r0, #IRQ_MODE /* Enter IRQ mode */
      msr     cpsr, r0
      ldr     sp, =irq_stack_top   /* Set irq stack */
      mrs     r0, cpsr          /* Switch back to old mode */
      bic     r0, r0, #MODE_MASK
      orr     r0, r0, r1        /* Restore old mode from r1 */
      msr     cpsr, r0
      bx      lr

	.ltorg