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forest-all-around/@sampler/Audio_SdFat.latest/output_spdif2.cpp

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/* SPDIF for Teensy 3.X
* Copyright (c) 2015, Frank Bösing, f.boesing@gmx.de,
* Thanks to KPC & Paul Stoffregen!
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice, development funding notice, and this permission
* notice shall be included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
// 2015/08/23: (FB) added mute_PCM() - sets or unsets VALID in VUCP (and adjusts PARITY)
#if defined(__IMXRT1052__) || defined(__IMXRT1062__)
#include <Arduino.h>
#include "output_spdif2.h"
#include "utility/imxrt_hw.h"
audio_block_t * AudioOutputSPDIF2::block_left_1st = NULL;
audio_block_t * AudioOutputSPDIF2::block_right_1st = NULL;
audio_block_t * AudioOutputSPDIF2::block_left_2nd = NULL;
audio_block_t * AudioOutputSPDIF2::block_right_2nd = NULL;
uint16_t AudioOutputSPDIF2::block_left_offset = 0;
uint16_t AudioOutputSPDIF2::block_right_offset = 0;
bool AudioOutputSPDIF2::update_responsibility = false;
DMAChannel AudioOutputSPDIF2::dma(false);
extern uint16_t spdif_bmclookup[256];
DMAMEM __attribute__((aligned(32)))
static uint32_t SPDIF_tx_buffer[AUDIO_BLOCK_SAMPLES * 4]; //2 KB
#define PREAMBLE_B (0xE8) //11101000
#define PREAMBLE_M (0xE2) //11100010
#define PREAMBLE_W (0xE4) //11100100
#define VUCP_VALID ((0xCC) << 24)
#define VUCP_INVALID ((0xD4) << 24)// To mute PCM, set VUCP = invalid.
uint32_t AudioOutputSPDIF2::vucp = VUCP_VALID;
PROGMEM
void AudioOutputSPDIF2::begin(void)
{
dma.begin(true); // Allocate the DMA channel first
block_left_1st = NULL;
block_right_1st = NULL;
// TODO: should we set & clear the I2S_TCSR_SR bit here?
config_SPDIF();
CORE_PIN2_CONFIG = 2; //2:TX_DATA0
const int nbytes_mlno = 2 * 4; // 8 Bytes per minor loop
dma.TCD->SADDR = SPDIF_tx_buffer;
dma.TCD->SOFF = 4;
dma.TCD->ATTR = DMA_TCD_ATTR_SSIZE(2) | DMA_TCD_ATTR_DSIZE(2);
dma.TCD->NBYTES_MLNO = nbytes_mlno;
dma.TCD->SLAST = -sizeof(SPDIF_tx_buffer);
dma.TCD->DADDR = &I2S2_TDR0;
dma.TCD->DOFF = 0;
dma.TCD->CITER_ELINKNO = sizeof(SPDIF_tx_buffer) / nbytes_mlno;
dma.TCD->DLASTSGA = 0;
dma.TCD->BITER_ELINKNO = sizeof(SPDIF_tx_buffer) / nbytes_mlno;
dma.TCD->CSR = DMA_TCD_CSR_INTHALF | DMA_TCD_CSR_INTMAJOR;
dma.triggerAtHardwareEvent(DMAMUX_SOURCE_SAI2_TX);
update_responsibility = update_setup();
dma.enable();
I2S2_TCSR |= I2S_TCSR_TE | I2S_TCSR_BCE | I2S_TCSR_FRDE | I2S_TCSR_FR;
dma.attachInterrupt(isr);
}
/*
http://www.hardwarebook.info/S/PDIF
1. To make it easier and a bit faster, the parity-bit is always the same.
- With a alternating parity we had to adjust the next subframe. Instead, use a bit from the aux-info as parity.
2. The buffer is filled with an offset of 1 byte, so the last parity (which is always 0 now (see 1.) ) is written as first byte.
-> A bit easier and faster to construct both subframes.
*/
void AudioOutputSPDIF2::isr(void)
{
static uint16_t frame = 0;
const int16_t *src;
int32_t *end, *dest;
audio_block_t *block;
uint32_t saddr, offset;
uint16_t sample, lo, hi, aux;
saddr = (uint32_t)(dma.TCD->SADDR);
dma.clearInterrupt();
if (saddr < (uint32_t)SPDIF_tx_buffer + sizeof(SPDIF_tx_buffer) / 2) {
// DMA is transmitting the first half of the buffer
// so we must fill the second half
dest = (int32_t *)&SPDIF_tx_buffer[AUDIO_BLOCK_SAMPLES * 4/2];
end = (int32_t *)&SPDIF_tx_buffer[AUDIO_BLOCK_SAMPLES * 4];
if (AudioOutputSPDIF2::update_responsibility) AudioStream::update_all();
} else {
// DMA is transmitting the second half of the buffer
// so we must fill the first half
dest = (int32_t *)SPDIF_tx_buffer;
end = (int32_t *)&SPDIF_tx_buffer[AUDIO_BLOCK_SAMPLES * 4/2];
}
block = AudioOutputSPDIF2::block_left_1st;
if (block) {
offset = AudioOutputSPDIF2::block_left_offset;
src = &block->data[offset];
do {
sample = *src++;
//Subframe Channel 1
hi = spdif_bmclookup[(uint8_t)(sample >> 8)];
lo = spdif_bmclookup[(uint8_t) sample];
lo ^= (~((int16_t)hi) >> 16);
// 16 Bit sample:
*(dest+1) = ((uint32_t)lo << 16) | hi;
// 4 Bit Auxillary-audio-databits, the first used as parity
aux = (0xB333 ^ (((uint32_t)((int16_t)lo)) >> 17));
if (++frame > 191) {
// VUCP-Bits ("Valid, Subcode, Channelstatus, Parity) = 0 (0xcc) | Preamble (depends on Framno.) | Auxillary
*(dest+0) = vucp | (PREAMBLE_B << 16 ) | aux; //special preamble for one of 192 frames
frame = 0;
} else {
*(dest+0) = vucp | (PREAMBLE_M << 16 ) | aux;
}
dest += 4;
} while (dest < end);
offset += AUDIO_BLOCK_SAMPLES/2;
if (offset < AUDIO_BLOCK_SAMPLES) {
AudioOutputSPDIF2::block_left_offset = offset;
} else {
AudioOutputSPDIF2::block_left_offset = 0;
AudioStream::release(block);
AudioOutputSPDIF2::block_left_1st = AudioOutputSPDIF2::block_left_2nd;
AudioOutputSPDIF2::block_left_2nd = NULL;
}
} else {
do {
if ( ++frame > 191 ) {
*(dest+0) = vucp | 0x00e8cccc;
frame = 0;
} else {
*(dest+0) = vucp | 0x00e2cccc;
}
*(dest+1) = 0xccccccccUL;
dest +=4;
} while (dest < end);
}
dest -= AUDIO_BLOCK_SAMPLES * 4/2 - 4/2;
block = AudioOutputSPDIF2::block_right_1st;
if (block) {
offset = AudioOutputSPDIF2::block_right_offset;
src = &block->data[offset];
do {
sample = *src++;
//Subframe Channel 2
hi = spdif_bmclookup[(uint8_t)(sample >> 8)];
lo = spdif_bmclookup[(uint8_t)sample];
lo ^= (~((int16_t)hi) >> 16);
*(dest+1) = ( ((uint32_t)lo << 16) | hi );
aux = (0xB333 ^ (((uint32_t)((int16_t)lo)) >> 17));
*(dest+0) = vucp | (PREAMBLE_W << 16 ) | aux;
dest += 4;
} while (dest < end);
offset += AUDIO_BLOCK_SAMPLES/2;
if (offset < AUDIO_BLOCK_SAMPLES) {
AudioOutputSPDIF2::block_right_offset = offset;
} else {
AudioOutputSPDIF2::block_right_offset = 0;
AudioStream::release(block);
AudioOutputSPDIF2::block_right_1st = AudioOutputSPDIF2::block_right_2nd;
AudioOutputSPDIF2::block_right_2nd = NULL;
}
} else {
do {
*dest = vucp | 0x00e4ccccUL;
*(dest+1) = 0xccccccccUL;
dest += 4 ;
} while (dest < end);
}
#if IMXRT_CACHE_ENABLED >= 2
dest -= AUDIO_BLOCK_SAMPLES * 4/2 + 4/2;
arm_dcache_flush_delete(dest, sizeof(SPDIF_tx_buffer) / 2 );
#endif
}
void AudioOutputSPDIF2::mute_PCM(const bool mute)
{
vucp = mute?VUCP_INVALID:VUCP_VALID;
}
void AudioOutputSPDIF2::update(void)
{
audio_block_t *block;
block = receiveReadOnly(0); // input 0 = left channel
if (block) {
__disable_irq();
if (block_left_1st == NULL) {
block_left_1st = block;
block_left_offset = 0;
__enable_irq();
} else if (block_left_2nd == NULL) {
block_left_2nd = block;
__enable_irq();
} else {
audio_block_t *tmp = block_left_1st;
block_left_1st = block_left_2nd;
block_left_2nd = block;
block_left_offset = 0;
__enable_irq();
release(tmp);
}
}
block = receiveReadOnly(1); // input 1 = right channel
if (block) {
__disable_irq();
if (block_right_1st == NULL) {
block_right_1st = block;
block_right_offset = 0;
__enable_irq();
} else if (block_right_2nd == NULL) {
block_right_2nd = block;
__enable_irq();
} else {
audio_block_t *tmp = block_right_1st;
block_right_1st = block_right_2nd;
block_right_2nd = block;
block_right_offset = 0;
__enable_irq();
release(tmp);
}
}
}
PROGMEM
void AudioOutputSPDIF2::config_SPDIF(void)
{
CCM_CCGR5 |= CCM_CCGR5_SAI2(CCM_CCGR_ON);
//PLL:
int fs = AUDIO_SAMPLE_RATE_EXACT;
// PLL between 27*24 = 648MHz und 54*24=1296MHz
int n1 = 4; //SAI prescaler 4 => (n1*n2) = multiple of 4
int n2 = 1 + (24000000 * 27) / (fs * 256 * n1);
double C = ((double)fs * 256 * n1 * n2) / 24000000;
int c0 = C;
int c2 = 10000;
int c1 = C * c2 - (c0 * c2);
set_audioClock(c0, c1, c2);
CCM_CSCMR1 = (CCM_CSCMR1 & ~(CCM_CSCMR1_SAI2_CLK_SEL_MASK))
| CCM_CSCMR1_SAI2_CLK_SEL(2); // &0x03 // (0,1,2): PLL3PFD0, PLL5, PLL4,
CCM_CS2CDR = (CCM_CS2CDR & ~(CCM_CS2CDR_SAI2_CLK_PRED_MASK | CCM_CS2CDR_SAI2_CLK_PODF_MASK))
| CCM_CS2CDR_SAI2_CLK_PRED(n1-1)
| CCM_CS2CDR_SAI2_CLK_PODF(n2-1);
IOMUXC_GPR_GPR1 = (IOMUXC_GPR_GPR1 & ~(IOMUXC_GPR_GPR1_SAI2_MCLK3_SEL_MASK))
| (IOMUXC_GPR_GPR1_SAI2_MCLK_DIR | IOMUXC_GPR_GPR1_SAI2_MCLK3_SEL(0)); //Select MCLK
// configure transmitter
I2S2_TMR = 0;
I2S2_TCR1 = I2S_TCR1_RFW(0); // watermark
I2S2_TCR2 = I2S_TCR2_SYNC(0) | I2S_TCR2_MSEL(1) | I2S_TCR2_BCD | I2S_TCR2_DIV(0);
I2S2_TCR3 = I2S_TCR3_TCE;
//4 Words per Frame 32 Bit Word-Length -> 128 Bit Frame-Length, MSB First:
I2S2_TCR4 = I2S_TCR4_FRSZ(3) | I2S_TCR4_SYWD(0) | I2S_TCR4_MF | I2S_TCR4_FSP | I2S_TCR4_FSD;
I2S2_TCR5 = I2S_TCR5_WNW(31) | I2S_TCR5_W0W(31) | I2S_TCR5_FBT(31);
#if 0
//debug only:
CORE_PIN5_CONFIG = 2; //2:MCLK 11.43MHz
CORE_PIN4_CONFIG = 2; //2:TX_BCLK 5 MHz
CORE_PIN3_CONFIG = 2; //2:TX_SYNC 44.1 KHz
#endif
}
#endif
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