rockbox/firmware/target/arm/s3c2440/gigabeat-fx/pcm-meg-fx.c

255 lines
6.3 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2006 by Michael Sevakis
*
* This program 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
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include <stdlib.h>
#include "system.h"
#include "kernel.h"
#include "logf.h"
#include "audio.h"
#include "sound.h"
#include "file.h"
#include "pcm-internal.h"
/* PCM interrupt routine lockout */
static struct
{
int locked;
unsigned long state;
} dma_play_lock =
{
.locked = 0,
.state = 0,
};
#define FIFO_COUNT ((IISFCON >> 6) & 0x3F)
/* Setup for the DMA controller */
#define DMA_CONTROL_SETUP ((1<<31) | (1<<29) | (1<<23) | (1<<22) | (1<<20))
/* DMA count has hit zero - no more data */
/* Get more data from the callback and top off the FIFO */
void fiq_handler(void) __attribute__((interrupt ("FIQ")));
/* Mask the DMA interrupt */
void pcm_play_lock(void)
{
if (++dma_play_lock.locked == 1)
bitset32(&INTMSK, DMA2_MASK);
}
/* Unmask the DMA interrupt if enabled */
void pcm_play_unlock(void)
{
if (--dma_play_lock.locked == 0)
bitclr32(&INTMSK, dma_play_lock.state);
}
void pcm_play_dma_init(void)
{
/* There seem to be problems when changing the IIS interface configuration
* when a clock is not present.
*/
bitset32(&CLKCON, 1<<17);
/* slave, transmit mode, 16 bit samples - MCLK 384fs - use 16.9344Mhz -
BCLK 32fs */
IISMOD = (1<<9) | (1<<8) | (2<<6) | (1<<3) | (1<<2) | (1<<0);
/* RX,TX off,on */
IISCON |= (1<<3) | (1<<2);
bitclr32(&CLKCON, 1<<17);
audiohw_init();
/* init GPIO */
GPCCON = (GPCCON & ~(3<<14)) | (1<<14);
GPCDAT |= (1<<7);
/* GPE4=I2SDO, GPE3=I2SDI, GPE2=CDCLK, GPE1=I2SSCLK, GPE0=I2SLRCK */
GPECON = (GPECON & ~0x3ff) | 0x2aa;
/* Do not service DMA requests, yet */
/* clear any pending int and mask it */
bitset32(&INTMSK, DMA2_MASK);
SRCPND = DMA2_MASK;
/* connect to FIQ */
bitset32(&INTMOD, DMA2_MASK);
}
void pcm_postinit(void)
{
audiohw_postinit();
}
void pcm_dma_apply_settings(void)
{
audiohw_set_frequency(pcm_fsel);
}
/* Connect the DMA and start filling the FIFO */
static void play_start_pcm(void)
{
/* clear pending DMA interrupt */
SRCPND = DMA2_MASK;
/* Flush any pending writes */
clean_dcache_range((char*)DISRC2-0x30000000, (DCON2 & 0xFFFFF) * 2);
/* unmask DMA interrupt when unlocking */
dma_play_lock.state = DMA2_MASK;
/* turn on the request */
IISCON |= (1<<5);
/* Activate the channel */
DMASKTRIG2 = 0x2;
/* turn off the idle */
IISCON &= ~(1<<3);
/* start the IIS */
IISCON |= (1<<0);
}
/* Disconnect the DMA and wait for the FIFO to clear */
static void play_stop_pcm(void)
{
/* Mask DMA interrupt */
bitset32(&INTMSK, DMA2_MASK);
/* De-Activate the DMA channel */
DMASKTRIG2 = 0x4;
/* are we playing? wait for the chunk to finish */
if (dma_play_lock.state != 0)
{
/* wait for the FIFO to empty and DMA to stop */
while ((IISCON & (1<<7)) || (DMASKTRIG2 & 0x2));
}
/* Keep interrupt masked when unlocking */
dma_play_lock.state = 0;
/* turn off the request */
IISCON &= ~(1<<5);
/* turn on the idle */
IISCON |= (1<<3);
/* stop the IIS */
IISCON &= ~(1<<0);
}
void pcm_play_dma_start(const void *addr, size_t size)
{
/* Enable the IIS clock */
bitset32(&CLKCON, 1<<17);
/* stop any DMA in progress - idle IIS */
play_stop_pcm();
/* connect DMA to the FIFO and enable the FIFO */
IISFCON = (1<<15) | (1<<13);
/* set DMA dest */
DIDST2 = (unsigned int)&IISFIFO;
/* IIS is on the APB bus, INT when TC reaches 0, fixed dest addr */
DIDSTC2 = 0x03;
/* set DMA source and options */
DISRC2 = (unsigned int)addr + 0x30000000;
/* How many transfers to make - we transfer half-word at a time = 2 bytes */
/* DMA control: CURR_TC int, single service mode, I2SSDO int, HW trig */
/* no auto-reload, half-word (16bit) */
DCON2 = DMA_CONTROL_SETUP | (size / 2);
DISRCC2 = 0x00; /* memory is on AHB bus, increment addresses */
play_start_pcm();
}
/* Promptly stop DMA transfers and stop IIS */
void pcm_play_dma_stop(void)
{
play_stop_pcm();
/* Disconnect the IIS clock */
bitclr32(&CLKCON, 1<<17);
}
void pcm_play_dma_pause(bool pause)
{
if (pause)
{
/* pause playback on current buffer */
play_stop_pcm();
}
else
{
/* restart playback on current buffer */
/* make sure we're aligned on left channel - skip any right
channel sample left waiting */
DISRC2 = (DCSRC2 + 2) & ~0x3;
DCON2 = DMA_CONTROL_SETUP | (DSTAT2 & 0xFFFFE);
play_start_pcm();
}
}
void fiq_handler(void)
{
static void *start;
static size_t size;
/* clear any pending interrupt */
SRCPND = DMA2_MASK;
/* Buffer empty. Try to get more. */
pcm_play_get_more_callback(&start, &size);
if (size == 0)
return;
/* Flush any pending cache writes */
clean_dcache_range(start, size);
/* set the new DMA values */
DCON2 = DMA_CONTROL_SETUP | (size >> 1);
DISRC2 = (unsigned int)start + 0x30000000;
/* Re-Activate the channel */
DMASKTRIG2 = 0x2;
pcm_play_dma_started_callback();
}
size_t pcm_get_bytes_waiting(void)
{
/* lie a little and only return full pairs */
return (DSTAT2 & 0xFFFFE) * 2;
}
const void * pcm_play_dma_get_peak_buffer(int *count)
{
unsigned long addr = DCSRC2;
int cnt = DSTAT2;
*count = (cnt & 0xFFFFF) >> 1;
return (void *)((addr + 2) & ~3);
}