main.c

arm嵌入式开发实例

//=============================================================================
// Filename:     main.c
//
// Description:  A sample driver application for the bootloader.
//
// Copyright (C) 2000 - 2002 Texas Instruments Incorporated
//
//============================================================================


#include "arm_boot.h"
#include "dsp_proj_code.h"
#include "dsp_proj_data.h"
#include <stdio.h>

// ---------------------- Interrupt Setup --------------------------------
#define SWI_CMD_SETSTK         1
#define SWI_MODE_FIQ           0x11
#define SWI_MODE_IRQ           0x12
#define SWI_MODE_SVC           0x13
#define SWI_CMD_SETCPSR        2
#define SWI_MASK_IRQ           0x80
#define SWI_IRQENABLE          0x00

#define ENABLE_IRQ_INTERRUPTS  SWI_Command(SWI_CMD_SETCPSR,    \
                                           SWI_MASK_IRQ,       \
                                           SWI_IRQENABLE)

int SWI_cmd, SWI_arg1, SWI_arg2;

static void SWI_Command(int cmd, unsigned long arg1, unsigned long arg2)
{
    SWI_cmd = cmd;
    SWI_arg1 = arg1;
    SWI_arg2 = arg2;
    asm(" SWIAL #0");
}

// ---------------------- Stack Setup -------------------------------
#define SVC_STACK_SIZE  128      
#define IRQ_STACK_SIZE  128      
#define FIQ_STACK_SIZE  128      

static unsigned long _svc_stack[SVC_STACK_SIZE];
static unsigned long _irq_stack[IRQ_STACK_SIZE];
static unsigned long _fiq_stack[FIQ_STACK_SIZE];

static void setupstacks()
{
    SWI_Command(SWI_CMD_SETSTK, SWI_MODE_SVC, 
                (unsigned long) _svc_stack + SVC_STACK_SIZE);
    SWI_Command(SWI_CMD_SETSTK, SWI_MODE_IRQ, 
                (unsigned long) _irq_stack + IRQ_STACK_SIZE);
    SWI_Command(SWI_CMD_SETSTK, SWI_MODE_FIQ, 
                (unsigned long) _fiq_stack + FIQ_STACK_SIZE);
} 

// ---------------------- Clock Setup --------------------------------
#define DSPCLK_ENABLE      0x00004000
#define MCLK_ENABLE        0x00008000

#define KBDIO_IO		   ((unsigned long *)0xFFFF2900)
#define KBDIO_CIO		   ((unsigned long *)0xFFFF2904)
#define KBDIO_EN  		   ((unsigned long *)0xFFFF2914)
#define KBDIO_IO1		   0x00000002



static unsigned long nandgpio( unsigned long *addr, unsigned long Data )
{
    unsigned long readback;
    
    readback = *addr;
   
    readback &= ~(Data);
    *addr = readback;

    return( readback );
}

static void EnableDSPCLK(void)
{  
    nandgpio(KBDIO_EN, DSPCLK_ENABLE);
}

static void EnableMCLK(void)
{  
    nandgpio(KBDIO_EN, MCLK_ENABLE);
}




// ---------------------- Main Driver --------------------------------



// set up a structure to represent the DSP program and data to be loaded
#define PMST 0xFF88

static dsp_app_struct test_dsp_app = 
                           {dsp_proj_program, dsp_proj_data, PMST};

main()
{
    resetinterrupts();
    setupstacks();

    pll_init(44, 100);  // setup arm and dsp PLLs
    EnableMCLK();       // enable external arm clock
    EnableDSPCLK();     // enable dsp clkout

    // enable DSP_XF output on KBGPIO1
    nandgpio(KBDIO_CIO, KBDIO_IO1);
    nandgpio(KBDIO_EN, KBDIO_IO1);

    // load the DSP with the program and data
    if (dsp_load(&test_dsp_app) != LOAD_OK) {
        while (1) {
        }
    }

    ENABLE_IRQ_INTERRUPTS;

    // set ILR__IRQ_15 to edge sensitive interrupt
    *((long *)0xffff2d58) = 0x00000020;
    
    // start the DSP
    dsp_start() ;

    // loop infinitely
    while (1) {
    }
}