andrewm@0: /*
andrewm@0:  * PRU.cpp
andrewm@0:  *
andrewm@0:  * Code for communicating with the Programmable Realtime Unit (PRU)
andrewm@0:  * on the BeagleBone AM335x series processors. The PRU loads and runs
andrewm@0:  * a separate code image compiled from an assembly file. Here it is
andrewm@0:  * used to handle audio and SPI ADC/DAC data.
andrewm@0:  *
andrewm@0:  * This code is specific to the PRU code in the assembly file; for example,
andrewm@0:  * it uses certain GPIO resources that correspond to that image.
andrewm@0:  *
andrewm@0:  *  Created on: May 27, 2014
andrewm@0:  *      Author: andrewm
andrewm@0:  */
andrewm@0: 
andrewm@0: #include "../include/PRU.h"
andrewm@0: #include "../include/prussdrv.h"
andrewm@0: #include "../include/pruss_intc_mapping.h"
giuliomoro@19: #include "../include/digital_gpio_mapping.h"
andrewm@0: #include "../include/GPIOcontrol.h"
andrewm@45: #include "../include/BeagleRT.h"
andrewm@15: #include "../include/pru_rtaudio_bin.h"
andrewm@0: 
andrewm@0: #include <iostream>
andrewm@0: #include <stdlib.h>
andrewm@0: #include <cstdio>
andrewm@0: #include <cerrno>
andrewm@0: #include <fcntl.h>
andrewm@0: #include <sys/mman.h>
giuliomoro@16: #include <unistd.h>
andrewm@0: 
andrewm@0: // Xenomai-specific includes
andrewm@0: #include <sys/mman.h>
andrewm@0: #include <native/task.h>
andrewm@0: #include <native/timer.h>
andrewm@0: #include <rtdk.h>
andrewm@0: 
andrewm@0: using namespace std;
andrewm@0: 
andrewm@0: #define PRU_MEM_MCASP_OFFSET 0x2000  // Offset within PRU-SHARED RAM
andrewm@253: #define PRU_MEM_MCASP_LENGTH 0x1000  // Length of McASP memory, in bytes
andrewm@0: #define PRU_MEM_DAC_OFFSET 0x0     // Offset within PRU0 RAM
andrewm@0: #define PRU_MEM_DAC_LENGTH 0x2000  // Length of ADC+DAC memory, in bytes
andrewm@0: #define PRU_MEM_COMM_OFFSET 0x0    // Offset within PRU-SHARED RAM
giuliomoro@19: #define PRU_MEM_DIGITAL_OFFSET 0x1000 //Offset within PRU-SHARED RAM
giuliomoro@19: #define MEM_DIGITAL_BUFFER1_OFFSET 0x400 //Start pointer to DIGITAL_BUFFER1, which is 256 words.
giuliomoro@16: 											// 256 is the maximum number of frames allowed
andrewm@0: #define PRU_SHOULD_STOP 	0
andrewm@0: #define PRU_CURRENT_BUFFER  1
andrewm@0: #define PRU_BUFFER_FRAMES   2
andrewm@0: #define PRU_SHOULD_SYNC     3
andrewm@0: #define PRU_SYNC_ADDRESS    4
andrewm@0: #define PRU_SYNC_PIN_MASK   5
andrewm@253: #define PRU_LED_ADDRESS	     6
andrewm@253: #define PRU_LED_PIN_MASK     7
andrewm@253: #define PRU_FRAME_COUNT      8
andrewm@253: #define PRU_USE_SPI          9
andrewm@12: #define PRU_SPI_NUM_CHANNELS 10
andrewm@253: #define PRU_USE_DIGITAL      11
andrewm@253: #define PRU_PRU_NUMBER       12
giuliomoro@16: 
giuliomoro@19: short int digitalPins[NUM_DIGITALS]={
giuliomoro@16: 		GPIO_NO_BIT_0,
giuliomoro@16: 		GPIO_NO_BIT_1,
giuliomoro@16: 		GPIO_NO_BIT_2,
giuliomoro@16: 		GPIO_NO_BIT_3,
giuliomoro@16: 		GPIO_NO_BIT_4,
giuliomoro@16: 		GPIO_NO_BIT_5,
giuliomoro@16: 		GPIO_NO_BIT_6,
giuliomoro@16: 		GPIO_NO_BIT_7,
giuliomoro@16: 		GPIO_NO_BIT_8,
giuliomoro@16: 		GPIO_NO_BIT_9,
giuliomoro@16: 		GPIO_NO_BIT_10,
giuliomoro@16: 		GPIO_NO_BIT_11,
giuliomoro@16: 		GPIO_NO_BIT_12,
giuliomoro@16: 		GPIO_NO_BIT_13,
giuliomoro@16: 		GPIO_NO_BIT_14,
giuliomoro@16: 		GPIO_NO_BIT_15,
giuliomoro@16: };
andrewm@0: 
andrewm@12: #define PRU_SAMPLE_INTERVAL_NS 11338	// 88200Hz per SPI sample = 11.338us
andrewm@0: 
andrewm@0: #define GPIO0_ADDRESS 		0x44E07000
andrewm@0: #define GPIO1_ADDRESS 		0x4804C000
andrewm@0: #define GPIO_SIZE			0x198
andrewm@0: #define GPIO_CLEARDATAOUT 	(0x190 / 4)
andrewm@0: #define GPIO_SETDATAOUT 	(0x194 / 4)
andrewm@0: 
andrewm@0: #define TEST_PIN_GPIO_BASE	GPIO0_ADDRESS	// Use GPIO0(31) for debugging
andrewm@0: #define TEST_PIN_MASK		(1 << 31)
andrewm@0: #define TEST_PIN2_MASK		(1 << 26)
andrewm@0: 
andrewm@0: #define USERLED3_GPIO_BASE  GPIO1_ADDRESS // GPIO1(24) is user LED 3
andrewm@0: #define USERLED3_PIN_MASK   (1 << 24)
andrewm@0: 
andrewm@0: const unsigned int PRU::kPruGPIODACSyncPin = 5;	// GPIO0(5); P9-17
andrewm@0: const unsigned int PRU::kPruGPIOADCSyncPin = 48; // GPIO1(16); P9-15
andrewm@0: 
andrewm@0: const unsigned int PRU::kPruGPIOTestPin = 60;	// GPIO1(28); P9-12
andrewm@0: const unsigned int PRU::kPruGPIOTestPin2 = 31;	// GPIO0(31); P9-13
andrewm@0: const unsigned int PRU::kPruGPIOTestPin3 = 26;	// GPIO0(26); P8-14
andrewm@0: 
giuliomoro@231: extern int gShouldStop;
andrewm@0: extern int gRTAudioVerbose;
andrewm@0: 
andrewm@0: // Constructor: specify a PRU number (0 or 1)
andrewm@45: PRU::PRU(BeagleRTContext *input_context)
andrewm@45: : context(input_context), pru_number(0), running(false), analog_enabled(false),
andrewm@45:   digital_enabled(false), gpio_enabled(false), led_enabled(false),
andrewm@45:   gpio_test_pin_enabled(false),
andrewm@45:   pru_buffer_comm(0), pru_buffer_spi_dac(0), pru_buffer_spi_adc(0),
andrewm@45:   pru_buffer_digital(0), pru_buffer_audio_dac(0), pru_buffer_audio_adc(0),
andrewm@45:   xenomai_gpio_fd(-1), xenomai_gpio(0)
andrewm@0: {
andrewm@0: 
andrewm@0: }
andrewm@0: 
andrewm@0: // Destructor
andrewm@0: PRU::~PRU()
andrewm@0: {
andrewm@0: 	if(running)
andrewm@0: 		disable();
andrewm@0: 	if(gpio_enabled)
andrewm@0: 		cleanupGPIO();
andrewm@0: 	if(xenomai_gpio_fd >= 0)
andrewm@0: 		close(xenomai_gpio_fd);
andrewm@0: }
andrewm@0: 
andrewm@0: // Prepare the GPIO pins needed for the PRU
andrewm@0: // If include_test_pin is set, the GPIO output
andrewm@0: // is also prepared for an output which can be
andrewm@0: // viewed on a scope. If include_led is set,
andrewm@0: // user LED 3 on the BBB is taken over by the PRU
andrewm@0: // to indicate activity
andrewm@45: int PRU::prepareGPIO(int include_test_pin, int include_led)
andrewm@0: {
andrewm@45: 	if(context->analogFrames != 0) {
andrewm@0: 		// Prepare DAC CS/ pin: output, high to begin
andrewm@0: 		if(gpio_export(kPruGPIODACSyncPin)) {
andrewm@0: 			if(gRTAudioVerbose)
andrewm@0: 				cout << "Warning: couldn't export DAC sync pin\n";
andrewm@0: 		}
andrewm@0: 		if(gpio_set_dir(kPruGPIODACSyncPin, OUTPUT_PIN)) {
andrewm@0: 			if(gRTAudioVerbose)
andrewm@0: 				cout << "Couldn't set direction on DAC sync pin\n";
andrewm@0: 			return -1;
andrewm@0: 		}
andrewm@0: 		if(gpio_set_value(kPruGPIODACSyncPin, HIGH)) {
andrewm@0: 			if(gRTAudioVerbose)
andrewm@0: 				cout << "Couldn't set value on DAC sync pin\n";
andrewm@0: 			return -1;
andrewm@0: 		}
andrewm@0: 
andrewm@0: 		// Prepare ADC CS/ pin: output, high to begin
andrewm@0: 		if(gpio_export(kPruGPIOADCSyncPin)) {
andrewm@0: 			if(gRTAudioVerbose)
andrewm@0: 				cout << "Warning: couldn't export ADC sync pin\n";
andrewm@0: 		}
andrewm@0: 		if(gpio_set_dir(kPruGPIOADCSyncPin, OUTPUT_PIN)) {
andrewm@0: 			if(gRTAudioVerbose)
andrewm@0: 				cout << "Couldn't set direction on ADC sync pin\n";
andrewm@0: 			return -1;
andrewm@0: 		}
andrewm@0: 		if(gpio_set_value(kPruGPIOADCSyncPin, HIGH)) {
andrewm@0: 			if(gRTAudioVerbose)
andrewm@0: 				cout << "Couldn't set value on ADC sync pin\n";
andrewm@0: 			return -1;
andrewm@0: 		}
andrewm@0: 
andrewm@45: 		analog_enabled = true;
andrewm@0: 	}
andrewm@0: 
andrewm@45: 	if(context->digitalFrames != 0){
andrewm@45: 		for(unsigned int i = 0; i < context->digitalChannels; i++){
giuliomoro@19: 			if(gpio_export(digitalPins[i])) {
giuliomoro@16: 				if(gRTAudioVerbose)
giuliomoro@38: 					cerr << "Warning: couldn't export digital GPIO pin " << digitalPins[i] << "\n"; // this is left as a warning because if the pin has been exported by somebody else, can still be used
giuliomoro@16: 			}
giuliomoro@38: 			if(gpio_set_dir(digitalPins[i], INPUT_PIN)) {
giuliomoro@16: 				if(gRTAudioVerbose)
giuliomoro@38: 					cerr << "Error: Couldn't set direction on digital GPIO pin " << digitalPins[i] << "\n";
giuliomoro@16: 				return -1;
giuliomoro@16: 			}
giuliomoro@16: 		}
andrewm@45: 		digital_enabled = true;
giuliomoro@16: 	}
giuliomoro@16: 
andrewm@0: 	if(include_test_pin) {
andrewm@0: 		// Prepare GPIO test output (for debugging), low to begin
andrewm@0: 		if(gpio_export(kPruGPIOTestPin)) {
andrewm@0: 			if(gRTAudioVerbose)
andrewm@0: 				cout << "Warning: couldn't export GPIO test pin\n";
andrewm@0: 		}
andrewm@0: 		if(gpio_set_dir(kPruGPIOTestPin, OUTPUT_PIN)) {
andrewm@0: 			if(gRTAudioVerbose)
andrewm@0: 				cout << "Couldn't set direction on GPIO test pin\n";
andrewm@0: 			return -1;
andrewm@0: 		}
andrewm@0: 		if(gpio_set_value(kPruGPIOTestPin, LOW)) {
andrewm@0: 			if(gRTAudioVerbose)
andrewm@0: 				cout << "Couldn't set value on GPIO test pin\n";
andrewm@0: 			return -1;
andrewm@0: 		}
andrewm@0: 
andrewm@0: 		if(gpio_export(kPruGPIOTestPin2)) {
andrewm@0: 			if(gRTAudioVerbose)
andrewm@0: 				cout << "Warning: couldn't export GPIO test pin 2\n";
andrewm@0: 		}
andrewm@0: 		if(gpio_set_dir(kPruGPIOTestPin2, OUTPUT_PIN)) {
andrewm@0: 			if(gRTAudioVerbose)
andrewm@0: 				cout << "Couldn't set direction on GPIO test pin 2\n";
andrewm@0: 			return -1;
andrewm@0: 		}
andrewm@0: 		if(gpio_set_value(kPruGPIOTestPin2, LOW)) {
andrewm@0: 			if(gRTAudioVerbose)
andrewm@0: 				cout << "Couldn't set value on GPIO test pin 2\n";
andrewm@0: 			return -1;
andrewm@0: 		}
andrewm@0: 
andrewm@0: 		if(gpio_export(kPruGPIOTestPin3)) {
andrewm@0: 			if(gRTAudioVerbose)
andrewm@0: 				cout << "Warning: couldn't export GPIO test pin 3\n";
andrewm@0: 		}
andrewm@0: 		if(gpio_set_dir(kPruGPIOTestPin3, OUTPUT_PIN)) {
andrewm@0: 			if(gRTAudioVerbose)
andrewm@0: 				cout << "Couldn't set direction on GPIO test pin 3\n";
andrewm@0: 			return -1;
andrewm@0: 		}
andrewm@0: 		if(gpio_set_value(kPruGPIOTestPin3, LOW)) {
andrewm@0: 			if(gRTAudioVerbose)
andrewm@0: 				cout << "Couldn't set value on GPIO test pin 3\n";
andrewm@0: 			return -1;
andrewm@0: 		}
andrewm@0: 		gpio_test_pin_enabled = true;
andrewm@0: 	}
andrewm@0: 
andrewm@0: 	if(include_led) {
andrewm@0: 		// Turn off system function for LED3 so it can be reused by PRU
andrewm@0: 		led_set_trigger(3, "none");
andrewm@0: 		led_enabled = true;
andrewm@0: 	}
andrewm@0: 
andrewm@0: 	gpio_enabled = true;
andrewm@0: 
andrewm@0: 	return 0;
andrewm@0: }
andrewm@0: 
andrewm@0: // Clean up the GPIO at the end
andrewm@0: void PRU::cleanupGPIO()
andrewm@0: {
andrewm@0: 	if(!gpio_enabled)
andrewm@0: 		return;
andrewm@45: 	if(analog_enabled) {
andrewm@0: 		gpio_unexport(kPruGPIODACSyncPin);
andrewm@0: 		gpio_unexport(kPruGPIOADCSyncPin);
andrewm@0: 	}
giuliomoro@19: 	if(digital_enabled){
andrewm@45: 		for(unsigned int i = 0; i < context->digitalChannels; i++){
giuliomoro@19: 			gpio_unexport(digitalPins[i]);
giuliomoro@16: 		}
giuliomoro@16: 	}
andrewm@0: 	if(gpio_test_pin_enabled) {
andrewm@0: 		gpio_unexport(kPruGPIOTestPin);
andrewm@0: 		gpio_unexport(kPruGPIOTestPin2);
andrewm@0: 		gpio_unexport(kPruGPIOTestPin3);
andrewm@0: 	}
andrewm@0: 	if(led_enabled) {
andrewm@0: 		// Set LED back to default eMMC status
andrewm@0: 		// TODO: make it go back to its actual value before this program,
andrewm@0: 		// rather than the system default
andrewm@0: 		led_set_trigger(3, "mmc1");
andrewm@0: 	}
andrewm@0: 	gpio_enabled = gpio_test_pin_enabled = false;
andrewm@0: }
andrewm@0: 
andrewm@0: // Initialise and open the PRU
andrewm@12: int PRU::initialise(int pru_num, int frames_per_buffer, int spi_channels, bool xenomai_test_pin)
andrewm@0: {
andrewm@0: 	uint32_t *pruMem = 0;
andrewm@0: 
andrewm@0: 	if(!gpio_enabled) {
andrewm@0: 		rt_printf("initialise() called before GPIO enabled\n");
andrewm@0: 		return 1;
andrewm@0: 	}
andrewm@0: 
andrewm@0: 	pru_number = pru_num;
andrewm@0: 
andrewm@0:     /* Initialize structure used by prussdrv_pruintc_intc   */
andrewm@0:     /* PRUSS_INTC_INITDATA is found in pruss_intc_mapping.h */
andrewm@0:     tpruss_intc_initdata pruss_intc_initdata = PRUSS_INTC_INITDATA;
andrewm@0: 
andrewm@0:     /* Allocate and initialize memory */
andrewm@0:     prussdrv_init();
andrewm@45:     if(prussdrv_open(PRU_EVTOUT_0)) {
andrewm@0:     	rt_printf("Failed to open PRU driver\n");
andrewm@0:     	return 1;
andrewm@0:     }
andrewm@0: 
andrewm@0:     /* Map PRU's INTC */
andrewm@0:     prussdrv_pruintc_init(&pruss_intc_initdata);
andrewm@0: 
andrewm@0:     /* Map PRU memory to pointers */
andrewm@0: 	prussdrv_map_prumem (PRUSS0_SHARED_DATARAM, (void **)&pruMem);
andrewm@0:     pru_buffer_comm = (uint32_t *)&pruMem[PRU_MEM_COMM_OFFSET/sizeof(uint32_t)];
andrewm@0: 	pru_buffer_audio_dac = (int16_t *)&pruMem[PRU_MEM_MCASP_OFFSET/sizeof(uint32_t)];
andrewm@0: 
andrewm@12: 	/* ADC memory starts 2(ch)*2(buffers)*bufsize samples later */
andrewm@45: 	pru_buffer_audio_adc = &pru_buffer_audio_dac[4 * context->audioFrames];
andrewm@0: 
andrewm@45: 	if(analog_enabled) {
andrewm@0: 		prussdrv_map_prumem (pru_number == 0 ? PRUSS0_PRU0_DATARAM : PRUSS0_PRU1_DATARAM, (void **)&pruMem);
andrewm@0: 		pru_buffer_spi_dac = (uint16_t *)&pruMem[PRU_MEM_DAC_OFFSET/sizeof(uint32_t)];
andrewm@0: 
andrewm@12: 		/* ADC memory starts after N(ch)*2(buffers)*bufsize samples */
andrewm@45: 		pru_buffer_spi_adc = &pru_buffer_spi_dac[2 * context->analogChannels * context->analogFrames];
andrewm@0: 	}
andrewm@0: 	else {
andrewm@0: 		pru_buffer_spi_dac = pru_buffer_spi_adc = 0;
andrewm@0: 	}
andrewm@0: 
giuliomoro@19: 	if(digital_enabled) {
giuliomoro@16: 		prussdrv_map_prumem (PRUSS0_SHARED_DATARAM, (void **)&pruMem);
giuliomoro@19: 		pru_buffer_digital = (uint32_t *)&pruMem[PRU_MEM_DIGITAL_OFFSET/sizeof(uint32_t)];
giuliomoro@16: 	}
giuliomoro@16: 	else {
giuliomoro@19: 		pru_buffer_digital = 0;
giuliomoro@16: 	}
andrewm@45: 
andrewm@0:     /* Set up flags */
andrewm@0:     pru_buffer_comm[PRU_SHOULD_STOP] = 0;
andrewm@0:     pru_buffer_comm[PRU_CURRENT_BUFFER] = 0;
andrewm@45:     pru_buffer_comm[PRU_BUFFER_FRAMES] = context->analogFrames;
andrewm@0:     pru_buffer_comm[PRU_SHOULD_SYNC] = 0;
andrewm@0:     pru_buffer_comm[PRU_SYNC_ADDRESS] = 0;
andrewm@0:     pru_buffer_comm[PRU_SYNC_PIN_MASK] = 0;
andrewm@253:     pru_buffer_comm[PRU_PRU_NUMBER] = pru_number;
andrewm@0:     if(led_enabled) {
andrewm@0:     	pru_buffer_comm[PRU_LED_ADDRESS] = USERLED3_GPIO_BASE;
andrewm@0:     	pru_buffer_comm[PRU_LED_PIN_MASK] = USERLED3_PIN_MASK;
andrewm@0:     }
andrewm@0:     else {
andrewm@0:     	pru_buffer_comm[PRU_LED_ADDRESS] = 0;
andrewm@0:     	pru_buffer_comm[PRU_LED_PIN_MASK] = 0;
andrewm@0:     }
andrewm@45:     if(analog_enabled) {
andrewm@0:     	pru_buffer_comm[PRU_USE_SPI] = 1;
andrewm@45:     	pru_buffer_comm[PRU_SPI_NUM_CHANNELS] = context->analogChannels;
andrewm@0:     }
andrewm@0:     else {
andrewm@0:     	pru_buffer_comm[PRU_USE_SPI] = 0;
andrewm@12:     	pru_buffer_comm[PRU_SPI_NUM_CHANNELS] = 0;
andrewm@0:     }
giuliomoro@19:     if(digital_enabled) {
giuliomoro@38:     	pru_buffer_comm[PRU_USE_DIGITAL] = 1;
giuliomoro@38: //TODO: add mask
giuliomoro@16:     }
giuliomoro@16:     else {
giuliomoro@38:     	pru_buffer_comm[PRU_USE_DIGITAL] = 0;
giuliomoro@38: 
giuliomoro@16:     }
andrewm@0: 
giuliomoro@38:     /* Clear ADC and DAC memory.*/
giuliomoro@38:     //TODO: this initialisation should only address the memory effectively used by these buffers, i.e.:depend on the number of frames
giuliomoro@38:     //  (otherwise might cause issues if we move memory locations later on)
andrewm@45:     if(analog_enabled) {
andrewm@0: 		for(int i = 0; i < PRU_MEM_DAC_LENGTH / 2; i++)
andrewm@0: 			pru_buffer_spi_dac[i] = 0;
giuliomoro@38: 		if(digital_enabled){
giuliomoro@38: 			for(int i = 0; i < PRU_MEM_DIGITAL_OFFSET*2; i++)
giuliomoro@38: 				pru_buffer_digital[i] = 0x0000ffff; // set to all inputs, to avoid unexpected spikes
giuliomoro@38: 		}
andrewm@0:     }
andrewm@0: 	for(int i = 0; i < PRU_MEM_MCASP_LENGTH / 2; i++)
andrewm@0: 		pru_buffer_audio_dac[i] = 0;
andrewm@45: 
andrewm@0: 	/* If using GPIO test pin for Xenomai (for debugging), initialise the pointer now */
andrewm@0: 	if(xenomai_test_pin && xenomai_gpio_fd < 0) {
andrewm@0: 		xenomai_gpio_fd = open("/dev/mem", O_RDWR);
andrewm@0: 		if(xenomai_gpio_fd < 0)
andrewm@0: 			rt_printf("Unable to open /dev/mem for GPIO test pin\n");
andrewm@0: 		else {
andrewm@0: 			xenomai_gpio = (uint32_t *)mmap(0, GPIO_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, xenomai_gpio_fd, TEST_PIN_GPIO_BASE);
andrewm@0: 			if(xenomai_gpio == MAP_FAILED) {
andrewm@0: 				rt_printf("Unable to map GPIO address for test pin\n");
andrewm@0: 				xenomai_gpio = 0;
andrewm@0: 				close(xenomai_gpio_fd);
andrewm@0: 				xenomai_gpio_fd = -1;
andrewm@0: 			}
andrewm@0: 		}
andrewm@0: 	}
andrewm@0: 
andrewm@81: 	// Allocate audio buffers
andrewm@81: 	context->audioIn = (float *)malloc(2 * context->audioFrames * sizeof(float));
andrewm@81: 	context->audioOut = (float *)malloc(2 * context->audioFrames * sizeof(float));
andrewm@81: 	if(context->audioIn == 0 || context->audioOut == 0) {
andrewm@81: 		rt_printf("Error: couldn't allocate audio buffers\n");
andrewm@81: 		return 1;
andrewm@81: 	}
andrewm@81: 
andrewm@81: 	// Allocate analog buffers
andrewm@81: 	if(analog_enabled) {
andrewm@81: 		context->analogIn = (float *)malloc(context->analogChannels * context->analogFrames * sizeof(float));
andrewm@81: 		context->analogOut = (float *)malloc(context->analogChannels * context->analogFrames * sizeof(float));
andrewm@81: 		last_analog_out_frame = (float *)malloc(context->analogChannels * sizeof(float));
andrewm@81: 
andrewm@81: 		if(context->analogIn == 0 || context->analogOut == 0 || last_analog_out_frame == 0) {
andrewm@81: 			rt_printf("Error: couldn't allocate analog buffers\n");
andrewm@81: 			return 1;
andrewm@81: 		}
andrewm@81: 
andrewm@81: 		memset(last_analog_out_frame, 0, context->analogChannels * sizeof(float));
andrewm@81: 	}
andrewm@81: 
andrewm@81: 	// Allocate digital buffers
andrewm@81: 	digital_buffer0 = pru_buffer_digital;
andrewm@81: 	digital_buffer1 = pru_buffer_digital + MEM_DIGITAL_BUFFER1_OFFSET / sizeof(uint32_t);
andrewm@81: 	if(digital_enabled) {
andrewm@81: 		last_digital_buffer = (uint32_t *)malloc(context->digitalFrames * sizeof(uint32_t)); //temp buffer to hold previous states
andrewm@81: 		if(last_digital_buffer == 0) {
andrewm@81: 			rt_printf("Error: couldn't allocate digital buffers\n");
andrewm@81: 			return 1;
andrewm@81: 		}
andrewm@81: 
andrewm@81: 		for(unsigned int n = 0; n < context->digitalFrames; n++){
andrewm@81: 			// Initialize lastDigitalFrames to all inputs
andrewm@81: 			last_digital_buffer[n] = 0x0000ffff;
andrewm@81: 		}
andrewm@81: 	}
andrewm@81: 
andrewm@81: 	context->digital = digital_buffer0;
andrewm@81: 
andrewm@0: 	return 0;
andrewm@0: }
andrewm@0: 
andrewm@0: // Run the code image in the specified file
giuliomoro@16: int PRU::start(char * const filename)
andrewm@0: {
andrewm@0: 	/* Clear any old interrupt */
andrewm@45: 	prussdrv_pru_clear_event(PRU_EVTOUT_0, PRU0_ARM_INTERRUPT);
andrewm@45: 
giuliomoro@16: 	/* Load and execute binary on PRU */
giuliomoro@16: 	if(filename[0] == '\0') { //if the string is empty, load the embedded code
giuliomoro@16: 		if(gRTAudioVerbose)
giuliomoro@16: 			rt_printf("Using embedded PRU code\n");
giuliomoro@16: 		if(prussdrv_exec_code(pru_number, PRUcode, sizeof(PRUcode))) {
giuliomoro@16: 			rt_printf("Failed to execute PRU code\n");
giuliomoro@16: 			return 1;
giuliomoro@16: 		}
giuliomoro@16: 	} else {
giuliomoro@16: 		if(gRTAudioVerbose)
giuliomoro@16: 			rt_printf("Using PRU code from %s\n",filename);
giuliomoro@16: 		if(prussdrv_exec_program(pru_number, filename)) {
giuliomoro@16: 			rt_printf("Failed to execute PRU code from %s\n", filename);
giuliomoro@16: 			return 1;
giuliomoro@16: 		}
giuliomoro@16: 	}
andrewm@0: 
andrewm@0:     running = true;
andrewm@0:     return 0;
andrewm@0: }
andrewm@0: 
andrewm@0: // Main loop to read and write data from/to PRU
andrewm@45: void PRU::loop(RT_INTR *pru_interrupt, void *userData)
andrewm@0: {
andrewm@50: #ifdef BEAGLERT_USE_XENOMAI_INTERRUPTS
andrewm@50: 	RTIME irqTimeout = PRU_SAMPLE_INTERVAL_NS * 1024;	// Timeout for PRU interrupt: about 10ms, much longer than any expected period
andrewm@50: #else
andrewm@0: 	// Polling interval is 1/4 of the period
andrewm@50: 	RTIME sleepTime = PRU_SAMPLE_INTERVAL_NS * (context->analogChannels / 2) * context->analogFrames / 4;
andrewm@50: #endif
andrewm@45: 
andrewm@45: 	uint32_t pru_audio_offset, pru_spi_offset;
andrewm@0: 
andrewm@81: 	// Before starting, look at the last state of the analog and digital outputs which might
andrewm@81: 	// have been changed by the user during the setup() function. This lets us start with pin
andrewm@81: 	// directions and output values at something other than defaults.
andrewm@81: 
andrewm@81: 	if(analog_enabled) {
andrewm@81: 		if(context->flags & BEAGLERT_FLAG_ANALOG_OUTPUTS_PERSIST) {
andrewm@81: 			// Remember the content of the last_analog_out_frame
andrewm@81: 			for(unsigned int ch = 0; ch < context->analogChannels; ch++){
andrewm@81: 				last_analog_out_frame[ch] = context->analogOut[context->analogChannels * (context->analogFrames - 1) + ch];
andrewm@81: 			}
andrewm@81: 		}
andrewm@0: 	}
andrewm@45: 
andrewm@45: 	if(digital_enabled) {
andrewm@45: 		for(unsigned int n = 0; n < context->digitalFrames; n++){
andrewm@81: 			last_digital_buffer[n] = context->digital[n];
andrewm@45: 		}
giuliomoro@38: 	}
andrewm@45: 
andrewm@45: 	// TESTING
andrewm@50: 	// uint32_t testCount = 0;
andrewm@45: 	// RTIME startTime = rt_timer_read();
andrewm@45: 
andrewm@56: #ifdef BEAGLERT_USE_XENOMAI_INTERRUPTS
andrewm@56: 	int result;
andrewm@56: #else
andrewm@50: 	// Which buffer the PRU was last processing
andrewm@50: 	uint32_t lastPRUBuffer = 0;
andrewm@50: #endif
andrewm@50: 
andrewm@0: 	while(!gShouldStop) {
andrewm@50: #ifdef BEAGLERT_USE_XENOMAI_INTERRUPTS
andrewm@45: 		// Wait for PRU to move to change buffers;
andrewm@45: 		// PRU will send an interrupts which we wait for
andrewm@45: 		rt_intr_enable(pru_interrupt);
andrewm@45: 		while(!gShouldStop) {
andrewm@45: 			result = rt_intr_wait(pru_interrupt, irqTimeout);
andrewm@45: 			if(result >= 0)
andrewm@45: 				break;
andrewm@45: 			else if(result == -ETIMEDOUT)
andrewm@45: 				rt_printf("Warning: PRU timeout!\n");
andrewm@45: 			else {
andrewm@45: 				rt_printf("Error: wait for interrupt failed (%d)\n", result);
andrewm@45: 				gShouldStop = 1;
andrewm@45: 			}
andrewm@0: 		}
andrewm@45: 
andrewm@45: 		// Clear pending PRU interrupt
andrewm@45: 		prussdrv_pru_clear_event(PRU_EVTOUT_1, PRU1_ARM_INTERRUPT);
andrewm@50: #else
andrewm@50: 		// Poll
andrewm@50: 		while(pru_buffer_comm[PRU_CURRENT_BUFFER] == lastPRUBuffer && !gShouldStop) {
andrewm@50: 			rt_task_sleep(sleepTime);
andrewm@50: 		}
andrewm@50: 
andrewm@50: 		lastPRUBuffer = pru_buffer_comm[PRU_CURRENT_BUFFER];
andrewm@50: #endif
andrewm@45: 
andrewm@0: 		if(gShouldStop)
andrewm@0: 			break;
andrewm@0: 
andrewm@45: 		// Check which buffer we're on-- will have been set right
andrewm@45: 		// before the interrupt was asserted
andrewm@45: 		if(pru_buffer_comm[PRU_CURRENT_BUFFER] == 1) {
andrewm@45: 			// PRU is on buffer 1. We read and write to buffer 0
andrewm@45: 			pru_audio_offset = 0;
andrewm@45: 			pru_spi_offset = 0;
andrewm@45: 			if(digital_enabled)
andrewm@81: 				context->digital = digital_buffer0;
andrewm@45: 		}
andrewm@45: 		else {
andrewm@45: 			// PRU is on buffer 0. We read and write to buffer 1
andrewm@45: 			pru_audio_offset = context->audioFrames * 2;
andrewm@45: 			pru_spi_offset = context->analogFrames * context->analogChannels;
andrewm@45: 			if(digital_enabled)
andrewm@81: 				context->digital = digital_buffer1;
andrewm@45: 		}
andrewm@45: 
andrewm@45: 		// FIXME: some sort of margin is needed here to prevent the audio
andrewm@45: 		// code from completely eating the Linux system
andrewm@50: 		// testCount++;
andrewm@45: 		//rt_task_sleep(sleepTime*4);
andrewm@45: 		//rt_task_sleep(sleepTime/4);
andrewm@45: 
andrewm@0: 		if(xenomai_gpio != 0) {
andrewm@0: 			// Set the test pin high
andrewm@0: 			xenomai_gpio[GPIO_SETDATAOUT] = TEST_PIN_MASK;
andrewm@0: 		}
andrewm@0: 
andrewm@45: 		// Convert short (16-bit) samples to float
andrewm@45: 		// TODO: NEON
andrewm@45: 		for(unsigned int n = 0; n < 2 * context->audioFrames; n++)
giuliomoro@231: 			context->audioIn[n] = (float)pru_buffer_audio_adc[n + pru_audio_offset] / 32768.0f;
andrewm@0: 
andrewm@45: 		if(analog_enabled) {
andrewm@45: 			// TODO: NEON
andrewm@45: 			for(unsigned int n = 0; n < context->analogChannels * context->analogFrames; n++)
giuliomoro@231: 				context->analogIn[n] = (float)pru_buffer_spi_adc[n + pru_spi_offset] / 65536.0f;
andrewm@45: 
andrewm@45: 			if(context->flags & BEAGLERT_FLAG_ANALOG_OUTPUTS_PERSIST) {
andrewm@45: 				// Initialize the output buffer with the values that were in the last frame of the previous output
andrewm@45: 				for(unsigned int ch = 0; ch < context->analogChannels; ch++){
andrewm@45: 					for(unsigned int n = 0; n < context->analogFrames; n++){
andrewm@81: 						context->analogOut[n * context->analogChannels + ch] = last_analog_out_frame[ch];
andrewm@45: 					}
giuliomoro@23: 				}
giuliomoro@23: 			}
andrewm@45: 			else {
andrewm@45: 				// Outputs are 0 unless set otherwise
andrewm@45: 				memset(context->analogOut, 0, context->analogChannels * context->analogFrames * sizeof(float));
giuliomoro@23: 			}
andrewm@45: 		}
andrewm@45: 
andrewm@45:         if(digital_enabled){
andrewm@45: 			// Use past digital values to initialize the array properly.
andrewm@45: 			// For each frame:
andrewm@45: 			// - pins previously set as outputs will keep the output value they had in the last frame of the previous buffer,
andrewm@45: 			// - pins previously set as inputs will carry the newly read input value
andrewm@45: 
andrewm@45: 			for(unsigned int n = 0; n < context->digitalFrames; n++){
andrewm@81: 				uint16_t inputs = last_digital_buffer[n] & 0xffff; // half-word, has 1 for inputs and 0 for outputs
andrewm@45: 
andrewm@45: 				uint16_t outputs = ~inputs; // half-word has 1 for outputs and 0 for inputs;
andrewm@81: 				context->digital[n] = (last_digital_buffer[context->digitalFrames - 1] & (outputs << 16)) | // keep output values set in the last frame of the previous buffer
andrewm@45: 									   (context->digital[n] & (inputs << 16))   | // inputs from current context->digital[n];
andrewm@81: 									   (last_digital_buffer[n] & (inputs));     // keep pin configuration from previous context->digital[n]
andrewm@45: //                    context->digital[n]=digitalBufferTemp[n]; //ignores inputs
andrewm@45: 			}
andrewm@45: 		}
andrewm@45: 
andrewm@45: 		// Call user render function
andrewm@45:         // ***********************
andrewm@45: 		render(context, userData);
andrewm@45: 		// ***********************
andrewm@45: 
andrewm@45: 		if(analog_enabled) {
andrewm@45: 			if(context->flags & BEAGLERT_FLAG_ANALOG_OUTPUTS_PERSIST) {
andrewm@81: 				// Remember the content of the last_analog_out_frame
andrewm@45: 				for(unsigned int ch = 0; ch < context->analogChannels; ch++){
andrewm@81: 					last_analog_out_frame[ch] = context->analogOut[context->analogChannels * (context->analogFrames - 1) + ch];
andrewm@45: 				}
andrewm@45: 			}
andrewm@45: 
andrewm@45: 			// Convert float back to short for SPI output
andrewm@45: 			for(unsigned int n = 0; n < context->analogChannels * context->analogFrames; n++) {
giuliomoro@231: 				int out = context->analogOut[n] * 65536.0f;
giuliomoro@16: 				if(out < 0) out = 0;
giuliomoro@16: 				else if(out > 65535) out = 65535;
andrewm@45: 				pru_buffer_spi_dac[n + pru_spi_offset] = (uint16_t)out;
giuliomoro@16: 			}
giuliomoro@16: 		}
andrewm@45: 
andrewm@45: 		if(digital_enabled) { // keep track of past digital values
andrewm@45: 			for(unsigned int n = 0; n < context->digitalFrames; n++){
andrewm@81: 				last_digital_buffer[n] = context->digital[n];
andrewm@45: 			}
andrewm@45: 		}
andrewm@45: 
andrewm@45:         // Convert float back to short for audio
andrewm@45: 		// TODO: NEON
andrewm@45: 		for(unsigned int n = 0; n < 2 * context->audioFrames; n++) {
giuliomoro@231: 			int out = context->audioOut[n] * 32768.0f;
andrewm@0: 			if(out < -32768) out = -32768;
andrewm@0: 			else if(out > 32767) out = 32767;
andrewm@45: 			pru_buffer_audio_dac[n + pru_audio_offset] = (int16_t)out;
andrewm@0: 		}
andrewm@0: 
andrewm@52: 		// Increment total number of samples that have elapsed
andrewm@52: 		context->audioSampleCount += context->audioFrames;
andrewm@52: 
andrewm@0: 		if(xenomai_gpio != 0) {
andrewm@0: 			// Set the test pin high
andrewm@0: 			xenomai_gpio[GPIO_CLEARDATAOUT] = TEST_PIN_MASK;
andrewm@0: 		}
andrewm@0: 
andrewm@45: 		// FIXME: TESTING!!
andrewm@50: 		// if(testCount > 100000)
andrewm@50: 		//	break;
andrewm@45: 	}
andrewm@0: 
andrewm@50: #ifdef BEAGLERT_USE_XENOMAI_INTERRUPTS
andrewm@45: 	// Turn off the interrupt for the PRU if it isn't already off
andrewm@45: 	rt_intr_disable(pru_interrupt);
andrewm@50: #endif
andrewm@0: 
andrewm@45: 	// FIXME: TESTING
andrewm@45: 	// RTIME endTime = rt_timer_read();
andrewm@45: 	// RTIME diffTime = endTime - startTime;
andrewm@45: 	// rt_printf("%d blocks elapsed in %f seconds, %f Hz block rate\n", testCount, ((float)diffTime / 1.0e9), (float)testCount / ((float)diffTime / 1.0e9));
andrewm@0: 
andrewm@0: 	// Tell PRU to stop
andrewm@0: 	pru_buffer_comm[PRU_SHOULD_STOP] = 1;
andrewm@0: 
andrewm@45: 	// Wait two buffer lengths for the PRU to finish
andrewm@45: 	rt_task_sleep(PRU_SAMPLE_INTERVAL_NS * context->analogFrames * 4 * 2);
andrewm@45: 
andrewm@45: 	// Clean up after ourselves
andrewm@45: 	free(context->audioIn);
andrewm@45: 	free(context->audioOut);
andrewm@45: 
andrewm@45: 	if(analog_enabled) {
andrewm@45: 		free(context->analogIn);
andrewm@45: 		free(context->analogOut);
andrewm@81: 		free(last_analog_out_frame);
andrewm@45: 	}
andrewm@45: 
andrewm@45: 	if(digital_enabled) {
andrewm@81: 		free(last_digital_buffer);
andrewm@45: 	}
andrewm@45: 
andrewm@45: 	context->audioIn = context->audioOut = 0;
andrewm@45: 	context->analogIn = context->analogOut = 0;
andrewm@45: 	context->digital = 0;
andrewm@0: }
andrewm@0: 
andrewm@0: // Wait for an interrupt from the PRU indicate it is finished
andrewm@0: void PRU::waitForFinish()
andrewm@0: {
andrewm@0: 	if(!running)
andrewm@0: 		return;
andrewm@45:     prussdrv_pru_wait_event (PRU_EVTOUT_0);
andrewm@45: 	prussdrv_pru_clear_event(PRU_EVTOUT_0, PRU0_ARM_INTERRUPT);
andrewm@0: }
andrewm@0: 
andrewm@0: // Turn off the PRU when done
andrewm@0: void PRU::disable()
andrewm@0: {
andrewm@0:     /* Disable PRU and close memory mapping*/
andrewm@0:     prussdrv_pru_disable(pru_number);
andrewm@0:     prussdrv_exit();
andrewm@0: 	running = false;
andrewm@0: }
andrewm@0: 
andrewm@0: // Debugging
andrewm@0: void PRU::setGPIOTestPin()
andrewm@0: {
andrewm@0: 	if(!xenomai_gpio)
andrewm@0: 		return;
andrewm@0: 	xenomai_gpio[GPIO_SETDATAOUT] = TEST_PIN2_MASK;
andrewm@0: }
andrewm@0: 
andrewm@0: void PRU::clearGPIOTestPin()
andrewm@0: {
andrewm@0: 	if(!xenomai_gpio)
andrewm@0: 		return;
andrewm@0: 	xenomai_gpio[GPIO_CLEARDATAOUT] = TEST_PIN2_MASK;
andrewm@0: }