i2s_audio_test.c

来自「eCos操作系统源码」· C语言 代码 · 共 233 行

//==========================================================================
//
//        i2s_audio_test.c
//
//        Cirrus CL7209 eval board CS4340 audio test
//
//==========================================================================
//####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
//
// eCos is free software; you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free
// Software Foundation; either version 2 or (at your option) any later version.
//
// eCos 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.  See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License along
// with eCos; if not, write to the Free Software Foundation, Inc.,
// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
//
// As a special exception, if other files instantiate templates or use macros
// or inline functions from this file, or you compile this file and link it
// with other works to produce a work based on this file, this file does not
// by itself cause the resulting work to be covered by the GNU General Public
// License. However the source code for this file must still be made available
// in accordance with section (3) of the GNU General Public License.
//
// This exception does not invalidate any other reasons why a work based on
// this file might be covered by the GNU General Public License.
//
// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
// at http://sources.redhat.com/ecos/ecos-license/
// -------------------------------------------
//####ECOSGPLCOPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):     gthomas
// Contributors:  gthomas
// Date:          2000-01-03
// Description:   Tool used to test AUDIO interface
//####DESCRIPTIONEND####

#include <pkgconf/kernel.h>   // Configuration header
#include <cyg/kernel/kapi.h>
#include <cyg/infra/diag.h>

#include <cyg/hal/hal_edb7xxx.h>  // Board definitions

#include <cyg/hal/hal_io.h>             // IO macros
#include <cyg/hal/hal_arch.h>           // Register state info
#include <cyg/hal/hal_diag.h>
#include <cyg/hal/hal_intr.h>           // HAL interrupt macros
#include <cyg/hal/drv_api.h>            // HAL ISR support

#if 1
#include "long_audio_left.h"
#include "long_audio_right.h"
#else
#include "short_audio_left.h"
#include "short_audio_right.h"
#endif

extern void i2s_FIQ(void);  // Actually the FIQ handler

// Number of data samples to play
#define NUM_PCM_SAMPLES (sizeof(left_channel)/sizeof(left_channel[0]))
// Play the data in 8 "chunks", truncated to multiple of 4 samples
#define CHUNK_LENGTH (((NUM_PCM_SAMPLES/8)/4)*4)

// This structure is used by the assembly coded interrupt routine
struct audio_buf {
    void *left_chan_ptr;
    void *right_chan_ptr;
    int   length;
};
volatile struct audio_buf cur_buf;
volatile struct audio_buf next_buf;

#ifndef FALSE
#define FALSE 0
#define TRUE  1
#endif

#define STACK_SIZE 4096
static char stack[STACK_SIZE];
static cyg_thread thread_data;
static cyg_handle_t thread_handle;

// FUNCTIONS

static void
cyg_test_exit(void)
{
    while (TRUE) ;
}

static void
I2Sreset(void)
{
    // Enable i2s interface instead of SSI#2
    *(volatile cyg_uint32 *)SYSCON3 |= SYSCON3_I2SSEL | 0x200;

    // Configure the i2s audio interface
    //   External clock, interrupt on right channel FIFO needs service
    *(volatile cyg_uint32 *)I2S_CTL = I2S_CTL_FLAG | I2S_CTL_ECS | I2S_CTL_RCTM;

    // Clear out status register
    *(volatile cyg_uint32 *)I2S_STAT = 0xFFFFFFFF;  // 1's reset

    // Now enable the interface
    *(volatile cyg_uint32 *)I2S_CTL |= I2S_CTL_EN;

    // Turn on the FIFOs
    while ((*(volatile cyg_uint32 *)I2S_STAT & I2S_STAT_FIFO) == 0) ;  // Wait   
    *(volatile cyg_uint32 *)I2S_STAT = I2S_STAT_FIFO;  // Reset flag
    *(volatile cyg_uint32 *)I2S_FIFO_CTL = I2S_FIFO_CTL_RIGHT_ENABLE;
    while ((*(volatile cyg_uint32 *)I2S_STAT & I2S_STAT_FIFO) == 0) ;  // Wait   
    *(volatile cyg_uint32 *)I2S_STAT = I2S_STAT_FIFO;  // Reset flag
    *(volatile cyg_uint32 *)I2S_FIFO_CTL = I2S_FIFO_CTL_LEFT_ENABLE;
    while ((*(volatile cyg_uint32 *)I2S_STAT & I2S_STAT_FIFO) == 0) ;  // Wait   
    *(volatile cyg_uint32 *)I2S_STAT = I2S_STAT_FIFO;  // Reset flag

    // Clear out status register
    *(volatile cyg_uint32 *)I2S_STAT = 0xFFFFFFFF;  // 1's reset

    // Enable interrupt
    *(volatile cyg_uint32 *)INTMR3 |= INTSR3_I2SINT;
}

static void
I2Sdisable(void)
{
    // Turn off the FIFOs
    while ((*(volatile cyg_uint32 *)I2S_STAT & I2S_STAT_FIFO) == 0) ;  // Wait   
    *(volatile cyg_uint32 *)I2S_STAT = I2S_STAT_FIFO;  // Reset flag
    *(volatile cyg_uint32 *)I2S_FIFO_CTL = I2S_FIFO_CTL_RIGHT_DISABLE;
    while ((*(volatile cyg_uint32 *)I2S_STAT & I2S_STAT_FIFO) == 0) ;  // Wait   
    *(volatile cyg_uint32 *)I2S_STAT = I2S_STAT_FIFO;  // Reset flag
    *(volatile cyg_uint32 *)I2S_FIFO_CTL = I2S_FIFO_CTL_LEFT_DISABLE;
    while ((*(volatile cyg_uint32 *)I2S_STAT & I2S_STAT_FIFO) == 0) ;  // Wait   
    *(volatile cyg_uint32 *)I2S_STAT = I2S_STAT_FIFO;  // Reset flag

    // Disable interrupt
    *(volatile cyg_uint32 *)INTMR3 &= ~INTSR3_I2SINT;

    // Disable the interface
    *(volatile cyg_uint32 *)I2S_CTL = 0;
}

static void
idle(void)
{
    // Do nothing
}

static void
audio_exercise(cyg_addrword_t p)
{
    int sample, len;
    bool started;

    diag_printf("AUDIO test here!\n");

    // Enable my special FIQ handler
    HAL_VSR_SET(CYGNUM_HAL_VECTOR_FIQ, i2s_FIQ, NULL);

    while (TRUE) {
        diag_printf("... Starting over\n");

        // Set up pointers
        cur_buf.length = 0;
        next_buf.length = 0;
        sample = 0;
        started = false;

        // Send out the data
        while (sample != NUM_PCM_SAMPLES) {
            if (next_buf.length == 0) {
                // Move some data into the "next" buffer
                next_buf.left_chan_ptr = &left_channel[sample];
                next_buf.right_chan_ptr = &right_channel[sample];
                len = NUM_PCM_SAMPLES - sample;
                if (len > CHUNK_LENGTH) len = CHUNK_LENGTH;
                next_buf.length = len;

                idle();

                if (!started) {
                    started = true;
                    // Initialize audio interface
                    I2Sreset();
                }
                sample += len;
            }
        }

        // Wait for all data to be sent
        while (cur_buf.length != 0) {
        }
        
        // Shut off audio interface
        I2Sdisable();
    }

    diag_printf("All done!\n");
    cyg_test_exit();
}

externC void
cyg_start( void )
{
    // Create a main thread, so we can run the scheduler and have time 'pass'
    cyg_thread_create(11,                // Priority - just a number
                      audio_exercise,    // entry
                      0,                 // initial parameter
                      "AUDIO_thread",    // Name
                      &stack[0],         // Stack
                      STACK_SIZE,        // Size
                      &thread_handle,    // Handle
                      &thread_data       // Thread data structure
            );
    cyg_thread_resume(thread_handle);  // Start it
    // Let 'em fly...
    cyg_scheduler_start();
} // cyg_package_start()