|  |  | @@ -0,0 +1,270 @@ | 
		
	
		
			
			|  |  |  | /* Hardware-SPDIF for Teensy 4 | 
		
	
		
			
			|  |  |  | * Copyright (c) 2019, Frank Bösing, f.boesing@gmx.de | 
		
	
		
			
			|  |  |  | * | 
		
	
		
			
			|  |  |  | * 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. | 
		
	
		
			
			|  |  |  | */ | 
		
	
		
			
			|  |  |  | /* | 
		
	
		
			
			|  |  |  | http://www.hardwarebook.info/S/PDIF | 
		
	
		
			
			|  |  |  | https://www.mikrocontroller.net/articles/S/PDIF | 
		
	
		
			
			|  |  |  | https://en.wikipedia.org/wiki/S/PDIF | 
		
	
		
			
			|  |  |  | */ | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | #if defined(__IMXRT1052__) || defined(__IMXRT1062__) | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | #include <Arduino.h> | 
		
	
		
			
			|  |  |  | #include "output_spdif3.h" | 
		
	
		
			
			|  |  |  | #include "utility/imxrt_hw.h" | 
		
	
		
			
			|  |  |  | #include "memcpy_audio.h" | 
		
	
		
			
			|  |  |  | #include <math.h> | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | audio_block_t * AudioOutputSPDIF3::block_left_1st = nullptr; | 
		
	
		
			
			|  |  |  | audio_block_t * AudioOutputSPDIF3::block_right_1st = nullptr; | 
		
	
		
			
			|  |  |  | audio_block_t * AudioOutputSPDIF3::block_left_2nd = nullptr; | 
		
	
		
			
			|  |  |  | audio_block_t * AudioOutputSPDIF3::block_right_2nd = nullptr; | 
		
	
		
			
			|  |  |  | bool AudioOutputSPDIF3::update_responsibility = false; | 
		
	
		
			
			|  |  |  | DMAChannel AudioOutputSPDIF3::dma(false); | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | DMAMEM  __attribute__((aligned(32))) | 
		
	
		
			
			|  |  |  | static int32_t SPDIF_tx_buffer[AUDIO_BLOCK_SAMPLES * 4]; | 
		
	
		
			
			|  |  |  | DMAMEM  __attribute__((aligned(32))) | 
		
	
		
			
			|  |  |  | audio_block_t AudioOutputSPDIF3::block_silent; | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | PROGMEM | 
		
	
		
			
			|  |  |  | void AudioOutputSPDIF3::begin(void) | 
		
	
		
			
			|  |  |  | { | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | dma.begin(true); // Allocate the DMA channel first | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | block_left_1st = nullptr; | 
		
	
		
			
			|  |  |  | block_right_1st = nullptr; | 
		
	
		
			
			|  |  |  | memset(&block_silent, 0, sizeof(block_silent)); | 
		
	
		
			
			|  |  |  | uint32_t fs = AUDIO_SAMPLE_RATE_EXACT; | 
		
	
		
			
			|  |  |  | // PLL between 27*24 = 648MHz und 54*24=1296MHz | 
		
	
		
			
			|  |  |  | // n1, n2 choosen for compatibility with I2S (same PLL frequency) : | 
		
	
		
			
			|  |  |  | 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); | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | double pllclock = (c0 + (double)c1 / c2) * 24000000; //677376000 Hz | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | //use new pred/podf values | 
		
	
		
			
			|  |  |  | n1 = 7; //0: divide by 1 (do not use with high input frequencies), 1:/2, 2: /3, 7:/8 | 
		
	
		
			
			|  |  |  | n2 = 0; //0: divide by 1, 7: divide by 8 | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | uint32_t clock = pllclock / (1 + n1) / (1 + n2); | 
		
	
		
			
			|  |  |  | uint32_t clkdiv = clock / (fs * 64); // 1 .. 128 | 
		
	
		
			
			|  |  |  | uint32_t mod = clock % (fs * 64); | 
		
	
		
			
			|  |  |  | if (mod > ((fs * 64) / 2)) clkdiv += 1; //nearest divider | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | CCM_CCGR5 &= ~CCM_CCGR5_SPDIF(CCM_CCGR_ON); //Clock gate off | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | CCM_CDCDR = (CCM_CDCDR & ~(CCM_CDCDR_SPDIF0_CLK_SEL_MASK | CCM_CDCDR_SPDIF0_CLK_PRED_MASK | CCM_CDCDR_SPDIF0_CLK_PODF_MASK)) | 
		
	
		
			
			|  |  |  | | CCM_CDCDR_SPDIF0_CLK_SEL(0) // 0 PLL4, 1 PLL3 PFD2, 2 PLL5, 3 pll3_sw_clk | 
		
	
		
			
			|  |  |  | | CCM_CDCDR_SPDIF0_CLK_PRED(n1) | 
		
	
		
			
			|  |  |  | | CCM_CDCDR_SPDIF0_CLK_PODF(n2); | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | CCM_CCGR5 |= CCM_CCGR5_SPDIF(CCM_CCGR_ON); //Clock gate on | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | if ((SPDIF_SCR & 0x400) != 0) {			//If default value: | 
		
	
		
			
			|  |  |  | SPDIF_SCR = SPDIF_SCR_SOFT_RESET;		//Reset SPDIF | 
		
	
		
			
			|  |  |  | while (SPDIF_SCR & SPDIF_SCR_SOFT_RESET) {;}	//Wait for Reset (takes 8 cycles) | 
		
	
		
			
			|  |  |  | SPDIF_SCR = 0; | 
		
	
		
			
			|  |  |  | } | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | SPDIF_SCR |= | 
		
	
		
			
			|  |  |  | SPDIF_SCR_RXFIFOFULL_SEL(0) |// Full interrupt if at least 1 sample in Rx left and right FIFOs | 
		
	
		
			
			|  |  |  | SPDIF_SCR_RXAUTOSYNC | | 
		
	
		
			
			|  |  |  | SPDIF_SCR_TXAUTOSYNC | | 
		
	
		
			
			|  |  |  | SPDIF_SCR_TXFIFOEMPTY_SEL(3) | // Empty interrupt if at most 4 sample in Tx left and right FIFOs | 
		
	
		
			
			|  |  |  | SPDIF_SCR_TXFIFO_CTRL(1) | // 0:Send zeros 1: normal operation | 
		
	
		
			
			|  |  |  | SPDIF_SCR_DMA_TX_EN | | 
		
	
		
			
			|  |  |  | //SPDIF_SCR_VALCTRL | // Outgoing Validity always clear | 
		
	
		
			
			|  |  |  | SPDIF_SCR_TXSEL(5) | //0:off and output 0, 1:Feed-though SPDIFIN, 5:Tx Normal operation | 
		
	
		
			
			|  |  |  | SPDIF_SCR_USRC_SEL(3); // No embedded U channel | 
		
	
		
			
			|  |  |  | SPDIF_SRCD = 0; | 
		
	
		
			
			|  |  |  | SPDIF_STCSCH = 0; | 
		
	
		
			
			|  |  |  | SPDIF_STCSCL = 0; | 
		
	
		
			
			|  |  |  |  | 
		
	
		
			
			|  |  |  | SPDIF_SRCD = 0; | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | SPDIF_STC = SPDIF_STC_TXCLK_SOURCE(1) //tx_clk input (from SPDIF0_CLK_ROOT) | 
		
	
		
			
			|  |  |  | | SPDIF_STC_SYSCLK_DF(0) | 
		
	
		
			
			|  |  |  | | SPDIF_STC_TXCLK_DF(clkdiv - 1); | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | 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 = DMA_TCD_NBYTES_MLOFFYES_NBYTES(nbytes_mlno) | DMA_TCD_NBYTES_DMLOE | | 
		
	
		
			
			|  |  |  | DMA_TCD_NBYTES_MLOFFYES_MLOFF(-8); | 
		
	
		
			
			|  |  |  | dma.TCD->SLAST = -sizeof(SPDIF_tx_buffer); | 
		
	
		
			
			|  |  |  | dma.TCD->DADDR = &SPDIF_STL; | 
		
	
		
			
			|  |  |  | dma.TCD->DOFF = 4; | 
		
	
		
			
			|  |  |  | dma.TCD->DLASTSGA = -8; | 
		
	
		
			
			|  |  |  | //dma.TCD->ATTR_DST = ((31 - __builtin_clz(8)) << 3); | 
		
	
		
			
			|  |  |  | dma.TCD->CITER_ELINKNO = sizeof(SPDIF_tx_buffer) / nbytes_mlno; | 
		
	
		
			
			|  |  |  | 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_SPDIF_TX); | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | update_responsibility = update_setup(); | 
		
	
		
			
			|  |  |  | dma.enable(); | 
		
	
		
			
			|  |  |  | dma.attachInterrupt(isr); | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | CORE_PIN14_CONFIG = 3;  //3:SPDIF_OUT | 
		
	
		
			
			|  |  |  | SPDIF_STC |= SPDIF_STC_TX_ALL_CLK_EN; | 
		
	
		
			
			|  |  |  | //	pinMode(13, OUTPUT); | 
		
	
		
			
			|  |  |  | } | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | void AudioOutputSPDIF3::isr(void) | 
		
	
		
			
			|  |  |  | { | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | const int16_t *src_left, *src_right; | 
		
	
		
			
			|  |  |  | const int32_t *end; | 
		
	
		
			
			|  |  |  | int32_t *dest; | 
		
	
		
			
			|  |  |  | audio_block_t *block_left, *block_right; | 
		
	
		
			
			|  |  |  | uint32_t saddr; | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | 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 = SPDIF_tx_buffer + AUDIO_BLOCK_SAMPLES*2; | 
		
	
		
			
			|  |  |  | end = SPDIF_tx_buffer + AUDIO_BLOCK_SAMPLES*4; | 
		
	
		
			
			|  |  |  | } else { | 
		
	
		
			
			|  |  |  | // DMA is transmitting the second half of the buffer | 
		
	
		
			
			|  |  |  | // so we must fill the first half | 
		
	
		
			
			|  |  |  | dest = SPDIF_tx_buffer; | 
		
	
		
			
			|  |  |  | end = SPDIF_tx_buffer + AUDIO_BLOCK_SAMPLES*2; | 
		
	
		
			
			|  |  |  | } | 
		
	
		
			
			|  |  |  | block_left = block_left_1st; | 
		
	
		
			
			|  |  |  | if (!block_left) block_left = &block_silent; | 
		
	
		
			
			|  |  |  | block_right = block_right_1st; | 
		
	
		
			
			|  |  |  | if (!block_right) block_right = &block_silent; | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | src_left = (const int16_t *)(block_left->data); | 
		
	
		
			
			|  |  |  | src_right = (const int16_t *)(block_right->data); | 
		
	
		
			
			|  |  |  |  | 
		
	
		
			
			|  |  |  | do { | 
		
	
		
			
			|  |  |  |  | 
		
	
		
			
			|  |  |  | *dest++ = (*src_left++) << 8; | 
		
	
		
			
			|  |  |  | *dest++ = (*src_right++) << 8; | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | *dest++ = (*src_left++) << 8; | 
		
	
		
			
			|  |  |  | *dest++ = (*src_right++) << 8; | 
		
	
		
			
			|  |  |  |  | 
		
	
		
			
			|  |  |  | *dest++ = (*src_left++) << 8; | 
		
	
		
			
			|  |  |  | *dest++ = (*src_right++) << 8; | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | *dest++ = (*src_left++) << 8; | 
		
	
		
			
			|  |  |  | *dest++ = (*src_right++) << 8; | 
		
	
		
			
			|  |  |  |  | 
		
	
		
			
			|  |  |  | #if IMXRT_CACHE_ENABLED >= 2 | 
		
	
		
			
			|  |  |  | SCB_CACHE_DCCIMVAC = (uint32_t) dest - 32; | 
		
	
		
			
			|  |  |  | #endif | 
		
	
		
			
			|  |  |  |  | 
		
	
		
			
			|  |  |  | } while (dest < end); | 
		
	
		
			
			|  |  |  |  | 
		
	
		
			
			|  |  |  | if (block_left != &block_silent) { | 
		
	
		
			
			|  |  |  | release(block_left); | 
		
	
		
			
			|  |  |  | #if IMXRT_CACHE_ENABLED > 0 | 
		
	
		
			
			|  |  |  | SCB_CACHE_DCCIMVAC = (uint32_t)block_left; | 
		
	
		
			
			|  |  |  | #endif | 
		
	
		
			
			|  |  |  | block_left_1st = block_left_2nd; | 
		
	
		
			
			|  |  |  | block_left_2nd = nullptr; | 
		
	
		
			
			|  |  |  | } | 
		
	
		
			
			|  |  |  | if (block_right != &block_silent) { | 
		
	
		
			
			|  |  |  | release(block_right); | 
		
	
		
			
			|  |  |  | #if IMXRT_CACHE_ENABLED > 0 | 
		
	
		
			
			|  |  |  | SCB_CACHE_DCCIMVAC = (uint32_t)block_right; | 
		
	
		
			
			|  |  |  | #endif | 
		
	
		
			
			|  |  |  | block_right_1st = block_right_2nd; | 
		
	
		
			
			|  |  |  | block_right_2nd = nullptr; | 
		
	
		
			
			|  |  |  | } | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | if (update_responsibility) update_all(); | 
		
	
		
			
			|  |  |  | //digitalWriteFast(13,!digitalReadFast(13)); | 
		
	
		
			
			|  |  |  | } | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | void AudioOutputSPDIF3::update(void) | 
		
	
		
			
			|  |  |  | { | 
		
	
		
			
			|  |  |  | audio_block_t *block_left, *block_right; | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | block_left = receiveReadOnly(0);  // input 0 | 
		
	
		
			
			|  |  |  | block_right = receiveReadOnly(1); // input 1 | 
		
	
		
			
			|  |  |  | __disable_irq(); | 
		
	
		
			
			|  |  |  | if (block_left) { | 
		
	
		
			
			|  |  |  | if (block_left_1st == nullptr) { | 
		
	
		
			
			|  |  |  | block_left_1st = block_left; | 
		
	
		
			
			|  |  |  | block_left = nullptr; | 
		
	
		
			
			|  |  |  | } else if (block_left_2nd == nullptr) { | 
		
	
		
			
			|  |  |  | block_left_2nd = block_left; | 
		
	
		
			
			|  |  |  | block_left = nullptr; | 
		
	
		
			
			|  |  |  | } else { | 
		
	
		
			
			|  |  |  | audio_block_t *tmp = block_left_1st; | 
		
	
		
			
			|  |  |  | block_left_1st = block_left_2nd; | 
		
	
		
			
			|  |  |  | block_left_2nd = block_left; | 
		
	
		
			
			|  |  |  | block_left = tmp; | 
		
	
		
			
			|  |  |  | } | 
		
	
		
			
			|  |  |  | } | 
		
	
		
			
			|  |  |  | if (block_right) { | 
		
	
		
			
			|  |  |  | if (block_right_1st == nullptr) { | 
		
	
		
			
			|  |  |  | block_right_1st = block_right; | 
		
	
		
			
			|  |  |  | block_right = nullptr; | 
		
	
		
			
			|  |  |  | } else if (block_right_2nd == nullptr) { | 
		
	
		
			
			|  |  |  | block_right_2nd = block_right; | 
		
	
		
			
			|  |  |  | block_right = nullptr; | 
		
	
		
			
			|  |  |  | } else { | 
		
	
		
			
			|  |  |  | audio_block_t *tmp = block_right_1st; | 
		
	
		
			
			|  |  |  | block_right_1st = block_right_2nd; | 
		
	
		
			
			|  |  |  | block_right_2nd = block_right; | 
		
	
		
			
			|  |  |  | block_right = tmp; | 
		
	
		
			
			|  |  |  | } | 
		
	
		
			
			|  |  |  | } | 
		
	
		
			
			|  |  |  | __enable_irq(); | 
		
	
		
			
			|  |  |  | if (block_left) { | 
		
	
		
			
			|  |  |  | release(block_left); | 
		
	
		
			
			|  |  |  | #if IMXRT_CACHE_ENABLED > 0 | 
		
	
		
			
			|  |  |  | SCB_CACHE_DCCIMVAC = (uint32_t)block_left; | 
		
	
		
			
			|  |  |  | #endif | 
		
	
		
			
			|  |  |  | } | 
		
	
		
			
			|  |  |  | if (block_right) { | 
		
	
		
			
			|  |  |  | release(block_right); | 
		
	
		
			
			|  |  |  | #if IMXRT_CACHE_ENABLED > 0 | 
		
	
		
			
			|  |  |  | SCB_CACHE_DCCIMVAC = (uint32_t)block_right; | 
		
	
		
			
			|  |  |  | #endif | 
		
	
		
			
			|  |  |  | } | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | } | 
		
	
		
			
			|  |  |  | 
 | 
		
	
		
			
			|  |  |  | void AudioOutputSPDIF3::mute_PCM(const bool mute) | 
		
	
		
			
			|  |  |  | { | 
		
	
		
			
			|  |  |  | if (mute) | 
		
	
		
			
			|  |  |  | SPDIF_SCR |= SPDIF_SCR_VALCTRL; | 
		
	
		
			
			|  |  |  | else | 
		
	
		
			
			|  |  |  | SPDIF_SCR &= ~SPDIF_SCR_VALCTRL; | 
		
	
		
			
			|  |  |  | } | 
		
	
		
			
			|  |  |  | #endif |