///*****************************************************************************
//
// startup.c - Boot code for Stellaris.
//
// Copyright (c) 2005,2006 Luminary Micro, Inc.  All rights reserved.
//
// Software License Agreement
//
// Luminary Micro, Inc. (LMI) is supplying this software for use solely and
// exclusively on LMI's Stellaris Family of microcontroller products.
//
// The software is owned by LMI and/or its suppliers, and is protected under
// applicable copyright laws.  All rights are reserved.  Any use in violation
// of the foregoing restrictions may subject the user to criminal sanctions
// under applicable laws, as well as to civil liability for the breach of the
// terms and conditions of this license.
//
// THIS SOFTWARE IS PROVIDED "AS IS".  NO WARRANTIES, WHETHER EXPRESS, IMPLIED
// OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE.
// LMI SHALL NOT, IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR
// CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
//
//*****************************************************************************

//*****************************************************************************
//
// Forward declaration of the default fault handlers.
//
//*****************************************************************************
void ResetISR(void);
static void NmiSR(void);
static void FaultISR(void);
extern void SysTick_irq_handler(void);

//*****************************************************************************
//
// The entry point for the application.
//
//*****************************************************************************
extern void entry(void);

//*****************************************************************************
//
// Reserve space for the system stack.
//
//*****************************************************************************
#ifndef STACK_SIZE
#define STACK_SIZE                              64
#endif
static unsigned long pulStack[STACK_SIZE];

//*****************************************************************************
//
// The minimal vector table for a Cortex M3.  Note that the proper constructs
// must be placed on this to ensure that it ends up at physical address
// 0x0000.0000.
//
//*****************************************************************************
__attribute__ ((section("vectors")))
void (* const g_pfnVectors[])(void) =
{
    (void (*)(void))((unsigned long)pulStack + sizeof(pulStack)),
    ResetISR,
    NmiSR,
    FaultISR,
    0,                                      // The MPU fault handler
    0,                                      // The bus fault handler
    0,                                      // The usage fault handler
    0,                                      // Reserved
    0,                                      // Reserved
    0,                                      // Reserved
    0,                                      // Reserved
    0,                                      // SVCall handler
    0,                                      // Debug monitor handler
    0,                                      // Reserved
    0,                                      // The PendSV handler
    SysTick_irq_handler                     // The SysTick handler
};

//*****************************************************************************
//
// The following are constructs created by the linker, indicating where the
// the "data" and "bss" segments reside in memory.  The initializers for the
// for the "data" segment resides immediately following the "text" segment.
//
//*****************************************************************************
extern unsigned long _etext;
extern unsigned long _data;
extern unsigned long _edata;
extern unsigned long _bss;
extern unsigned long _ebss;

//*****************************************************************************
//
// Variable used for indexing when zeroing ZI section
// (so it doesn't zero itself)
//
//*****************************************************************************
static unsigned long *g_pulDest = (unsigned long*)4;

//*****************************************************************************
//
// Handler for the "reset" interrupt.
//
// This is the code that gets called when the processor first starts execution
// following a reset event.  Only the absolutely necessary set is performed,
// after which the application supplied entry() routine is called.  Any fancy
// actions (such as making decisions based on the reset cause register, and
// resetting the bits in that register) are left solely in the hands of the
// application.
//
//*****************************************************************************
void
ResetISR(void)
{
    unsigned long *pulSrc, *pulDest;

#if 1
    //
    // Copy the data segment initializers from FLASH to SRAM.
    //
    pulSrc = &_etext;
    for(pulDest = &_data; pulDest < &_edata; )
    {
        *pulDest++ = *pulSrc++;
    }

    //
    // Zero fill the bss segment.
    //
    for(g_pulDest = &_bss; g_pulDest < &_ebss; )
    {
        *g_pulDest++ = 0;
    }
#endif

    //
    // Call the application's entry point.
    //
    entry();
}

//*****************************************************************************
//
// Handler for the "nmi" interrupt.
//
// This is the code that gets called when the processor receives a NMI.  At
// present, this simply enters an infinite loop, preserving the system state
// for examination by a debugger.
//
//*****************************************************************************
static void
NmiSR(void)
{
    //
    // For now, enter an infinite loop.  This preserves the state of the system
    // so it can be examined via a debugger.
    //
    while(1)
    {
    }
}

//*****************************************************************************
//
// Handler for the "fault" interrupt.
//
// This is the code that gets called when the processor receives a fault
// interrupt.  At present, this simply enters an infinite loop, preserving the
// system state for examination by a debugger.
//
//*****************************************************************************
static void
FaultISR(void)
{
    //
    // For now, enter an infinite loop.  This preserves the state of the system
    // so it can be examined via a debugger.
    //
    while(1)
    {
    }
}
