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rockbox/firmware/target/arm/as3525/pcm-as3525.c
Mihail Zenkov e7550a4f6e AMS: Change DMA transfer size for audio. 
Slightly reduces power consumption due to DMA overhead.

Change-Id: I8576e9e243ce13a71cde710c3a726dce19bafb97
2015-06-01 18:23:57 +02:00

427 lines
11 KiB
C
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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright © 2008-2009 Rafaël Carré
*
* 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 "system.h"
#include "audio.h"
#include "string.h"
#include "as3525.h"
#include "pl081.h"
#include "dma-target.h"
#include "clock-target.h"
#include "panic.h"
#include "as3514.h"
#include "audiohw.h"
#include "mmu-arm.h"
#include "pcm-internal.h"
#define MAX_TRANSFER (4*((1<<11)-1)) /* maximum data we can transfer via DMA
* i.e. 32 bits at once (size of I2SO_DATA)
* and the number of 32bits words has to
* fit in 11 bits of DMA register */
static const void *dma_start_addr; /* Pointer to callback buffer */
static size_t dma_start_size; /* Size of callback buffer */
static const void *dma_sub_addr; /* Pointer to sub buffer */
static size_t dma_rem_size; /* Remaining size - in 4*32 bits */
static size_t play_sub_size; /* size of current subtransfer */
static void dma_callback(void);
static int locked = 0;
static bool volatile is_playing = false;
static bool play_callback_pending = false;
#ifdef HAVE_RECORDING
/* Stopping playback gates clock if not recording */
static bool volatile is_recording = false;
#endif
/* Mask the DMA interrupt */
void pcm_play_lock(void)
{
++locked;
}
/* Unmask the DMA interrupt if enabled */
void pcm_play_unlock(void)
{
if(--locked == 0 && is_playing)
{
int old = disable_irq_save();
if(play_callback_pending)
{
play_callback_pending = false;
dma_callback();
}
restore_irq(old);
}
}
static void play_start_pcm(void)
{
const void *addr = dma_sub_addr;
size_t size = dma_rem_size;
if(size > MAX_TRANSFER)
size = MAX_TRANSFER;
play_sub_size = size;
dma_enable_channel(0, (void*)addr, (void*)I2SOUT_DATA, DMA_PERI_I2SOUT,
DMAC_FLOWCTRL_DMAC_MEM_TO_PERI, true, false, size >> 2,
DMA_S16, dma_callback);
}
static void dma_callback(void)
{
dma_sub_addr += play_sub_size;
dma_rem_size -= play_sub_size;
play_sub_size = 0; /* Might get called again if locked */
if(locked)
{
play_callback_pending = is_playing;
return;
}
if(!dma_rem_size)
{
if(!pcm_play_dma_complete_callback(PCM_DMAST_OK, &dma_start_addr,
&dma_start_size))
return;
dma_sub_addr = dma_start_addr;
dma_rem_size = dma_start_size;
/* force writeback */
commit_dcache_range(dma_start_addr, dma_start_size);
play_start_pcm();
pcm_play_dma_status_callback(PCM_DMAST_STARTED);
}
else
{
play_start_pcm();
}
}
void pcm_play_dma_start(const void *addr, size_t size)
{
is_playing = true;
dma_start_addr = addr;
dma_start_size = size;
dma_sub_addr = dma_start_addr;
dma_rem_size = size;
dma_retain();
/* force writeback */
commit_dcache_range(dma_start_addr, dma_start_size);
play_start_pcm();
}
void pcm_play_dma_stop(void)
{
is_playing = false;
dma_disable_channel(0);
/* Ensure byte counts read back 0 */
DMAC_CH_SRC_ADDR(0) = 0;
dma_start_addr = NULL;
dma_start_size = 0;
dma_rem_size = 0;
dma_release();
play_callback_pending = false;
}
void pcm_play_dma_pause(bool pause)
{
is_playing = !pause;
if(pause)
{
dma_pause_channel(0);
/* if producer's buffer finished, upper layer starts anew */
if (dma_rem_size == 0)
play_callback_pending = false;
}
else
{
if (play_sub_size != 0)
dma_resume_channel(0);
/* else unlock calls the callback if sub buffers remain */
}
}
void pcm_play_dma_init(void)
{
bitset32(&CGU_PERI, CGU_I2SOUT_APB_CLOCK_ENABLE);
I2SOUT_CONTROL = (1<<6) | (1<<3); /* enable dma, stereo */
audiohw_preinit();
pcm_dma_apply_settings();
}
void pcm_play_dma_postinit(void)
{
audiohw_postinit();
}
/* divider is 9 bits but the highest one (for 8kHz) fit in 8 bits */
static const unsigned char divider[SAMPR_NUM_FREQ] = {
[HW_FREQ_96] = ((AS3525_MCLK_FREQ/128 + SAMPR_96/2) / SAMPR_96) - 1,
[HW_FREQ_88] = ((AS3525_MCLK_FREQ/128 + SAMPR_88/2) / SAMPR_88) - 1,
[HW_FREQ_64] = ((AS3525_MCLK_FREQ/128 + SAMPR_64/2) / SAMPR_64) - 1,
[HW_FREQ_48] = ((AS3525_MCLK_FREQ/128 + SAMPR_48/2) / SAMPR_48) - 1,
[HW_FREQ_44] = ((AS3525_MCLK_FREQ/128 + SAMPR_44/2) / SAMPR_44) - 1,
[HW_FREQ_32] = ((AS3525_MCLK_FREQ/128 + SAMPR_32/2) / SAMPR_32) - 1,
[HW_FREQ_24] = ((AS3525_MCLK_FREQ/128 + SAMPR_24/2) / SAMPR_24) - 1,
[HW_FREQ_22] = ((AS3525_MCLK_FREQ/128 + SAMPR_22/2) / SAMPR_22) - 1,
[HW_FREQ_16] = ((AS3525_MCLK_FREQ/128 + SAMPR_16/2) / SAMPR_16) - 1,
[HW_FREQ_12] = ((AS3525_MCLK_FREQ/128 + SAMPR_12/2) / SAMPR_12) - 1,
[HW_FREQ_11] = ((AS3525_MCLK_FREQ/128 + SAMPR_11/2) / SAMPR_11) - 1,
[HW_FREQ_8 ] = ((AS3525_MCLK_FREQ/128 + SAMPR_8 /2) / SAMPR_8 ) - 1,
};
static inline unsigned char mclk_divider(void)
{
return divider[pcm_fsel];
}
void pcm_dma_apply_settings(void)
{
bitmod32(&CGU_AUDIO,
(0<<24) | /* I2SI_MCLK2PAD_EN = disabled */
(0<<23) | /* I2SI_MCLK_EN = disabled */
(0<<14) | /* I2SI_MCLK_DIV_SEL = unused */
(0<<12) | /* I2SI_MCLK_SEL = clk_main */
(1<<11) | /* I2SO_MCLK_EN */
(mclk_divider() << 2) | /* I2SO_MCLK_DIV_SEL */
(AS3525_MCLK_SEL << 0), /* I2SO_MCLK_SEL */
0x01ffffff);
}
size_t pcm_get_bytes_waiting(void)
{
int oldstatus = disable_irq_save();
size_t addr = DMAC_CH_SRC_ADDR(0);
size_t start_addr = (size_t)dma_start_addr;
size_t start_size = dma_start_size;
restore_interrupt(oldstatus);
return start_size - addr + start_addr;
}
const void * pcm_play_dma_get_peak_buffer(int *count)
{
int oldstatus = disable_irq_save();
size_t addr = DMAC_CH_SRC_ADDR(0);
size_t start_addr = (size_t)dma_start_addr;
size_t start_size = dma_start_size;
restore_interrupt(oldstatus);
*count = (start_size - addr + start_addr) >> 2;
return (void*)AS3525_UNCACHED_ADDR(addr);
}
#ifdef HAVE_PCM_DMA_ADDRESS
void * pcm_dma_addr(void *addr)
{
if (addr != NULL)
addr = AS3525_UNCACHED_ADDR(addr);
return addr;
}
#endif
/****************************************************************************
** Recording DMA transfer
**/
#ifdef HAVE_RECORDING
static int rec_locked = 0;
static uint32_t *rec_dma_addr;
static size_t rec_dma_size;
static int keep_sample = 0; /* In nonzero, keep the sample; else, discard it */
void pcm_rec_lock(void)
{
int oldlevel = disable_irq_save();
if (++rec_locked == 1)
{
bitset32(&CGU_PERI, CGU_I2SIN_APB_CLOCK_ENABLE);
VIC_INT_EN_CLEAR = INTERRUPT_I2SIN;
I2SIN_MASK = 0; /* disables all interrupts */
}
restore_irq(oldlevel);
}
void pcm_rec_unlock(void)
{
int oldlevel = disable_irq_save();
if (--rec_locked == 0 && is_recording)
{
VIC_INT_ENABLE = INTERRUPT_I2SIN;
I2SIN_MASK = (1<<2); /* I2SIN_MASK_POAF */
}
restore_irq(oldlevel);
}
void INT_I2SIN(void)
{
#if CONFIG_CPU == AS3525
if (audio_channels == 1)
{
/* RX is left-channel-only mono */
while (rec_dma_size > 0)
{
if (I2SIN_RAW_STATUS & (1<<5))
return; /* empty */
uint32_t value = *I2SIN_DATA;
/* Discard every other sample since ADC clock is 1/2 LRCK */
keep_sample ^= 1;
if (keep_sample)
{
/* Data is in left channel only - copy to right channel
14-bit => 16-bit samples */
value = (uint16_t)(value << 2) | (value << 18);
if (audio_output_source != AUDIO_SRC_PLAYBACK && !is_playing)
{
/* In this case, loopback is manual so that both output
channels have audio */
if (I2SOUT_RAW_STATUS & (1<<5))
{
/* Sync output fifo so it goes empty not before input is
filled */
for (unsigned i = 0; i < 4; i++)
*I2SOUT_DATA = 0;
}
*I2SOUT_DATA = value;
*I2SOUT_DATA = value;
}
*rec_dma_addr++ = value;
rec_dma_size -= 4;
}
}
}
else
#endif /* CONFIG_CPU == AS3525 */
{
/* RX is stereo */
while (rec_dma_size > 0)
{
if (I2SIN_RAW_STATUS & (1<<5))
return; /* empty */
uint32_t value = *I2SIN_DATA;
/* Discard every other sample since ADC clock is 1/2 LRCK */
keep_sample ^= 1;
if (keep_sample)
{
/* Loopback is in I2S hardware */
/* 14-bit => 16-bit samples */
*rec_dma_addr++ = (value << 2) & ~0x00030000;
rec_dma_size -= 4;
}
}
}
/* Inform middle layer */
if (pcm_rec_dma_complete_callback(PCM_DMAST_OK, (void **)&rec_dma_addr,
&rec_dma_size))
{
pcm_rec_dma_status_callback(PCM_DMAST_STARTED);
}
}
void pcm_rec_dma_stop(void)
{
is_recording = false;
VIC_INT_EN_CLEAR = INTERRUPT_I2SIN;
I2SIN_MASK = 0; /* disables all interrupts */
rec_dma_addr = NULL;
rec_dma_size = 0;
bitclr32(&CGU_PERI, CGU_I2SIN_APB_CLOCK_ENABLE);
}
void pcm_rec_dma_start(void *addr, size_t size)
{
is_recording = true;
rec_dma_addr = addr;
rec_dma_size = size;
keep_sample = 0;
/* ensure empty FIFO */
while (!(I2SIN_RAW_STATUS & (1<<5)))
*I2SIN_DATA;
I2SIN_CLEAR = (1<<6) | (1<<0); /* push error, pop error */
}
void pcm_rec_dma_close(void)
{
bitset32(&CGU_PERI, CGU_I2SIN_APB_CLOCK_ENABLE);
pcm_rec_dma_stop();
}
void pcm_rec_dma_init(void)
{
bitset32(&CGU_PERI, CGU_I2SIN_APB_CLOCK_ENABLE);
I2SIN_MASK = 0; /* disables all interrupts */
/* 14 bits samples, i2c clk src = I2SOUTIF, sdata src = AFE,
* data valid at positive edge of SCLK */
I2SIN_CONTROL = (1<<5) | (1<<2);
}
const void * pcm_rec_dma_get_peak_buffer(void)
{
return rec_dma_addr;
}
#endif /* HAVE_RECORDING */
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