[FLYWOOF411] add board documentation

[inav/snaewe.git] / src / main / blackbox / blackbox_io.c

/*
 * This file is part of Cleanflight.
 *
 * Cleanflight 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 3 of the License, or
 * (at your option) any later version.
 *
 * Cleanflight is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Cleanflight.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdlib.h>
#include <stdarg.h>
#include <string.h>

#include "platform.h"

#ifdef USE_BLACKBOX

#include "blackbox.h"
#include "blackbox_io.h"

#include "common/axis.h"
#include "common/encoding.h"
#include "common/maths.h"
#include "common/printf.h"
#include "common/typeconversion.h"

#include "config/parameter_group.h"
#include "config/parameter_group_ids.h"

#include "io/asyncfatfs/asyncfatfs.h"
#include "io/flashfs.h"
#include "io/serial.h"

#include "msp/msp_serial.h"

#include "sensors/gyro.h"

#define BLACKBOX_SERIAL_PORT_MODE MODE_TX

// How many bytes can we transmit per loop iteration when writing headers?
static uint8_t blackboxMaxHeaderBytesPerIteration;

// How many bytes can we write *this* iteration without overflowing transmit buffers or overstressing the OpenLog?
int32_t blackboxHeaderBudget;

STATIC_UNIT_TESTED serialPort_t *blackboxPort = NULL;
#ifndef UNIT_TEST
static portSharing_e blackboxPortSharing;
#endif // UNIT_TEST

#ifdef USE_SDCARD

static struct {
    afatfsFilePtr_t logFile;
    afatfsFilePtr_t logDirectory;
    afatfsFinder_t logDirectoryFinder;
    uint32_t largestLogFileNumber;

    enum {
        BLACKBOX_SDCARD_INITIAL,
        BLACKBOX_SDCARD_WAITING,
        BLACKBOX_SDCARD_ENUMERATE_FILES,
        BLACKBOX_SDCARD_CHANGE_INTO_LOG_DIRECTORY,
        BLACKBOX_SDCARD_READY_TO_CREATE_LOG,
        BLACKBOX_SDCARD_READY_TO_LOG
    } state;
} blackboxSDCard;

#endif

#ifndef UNIT_TEST
void blackboxOpen(void)
{
    serialPort_t *sharedBlackboxAndMspPort = findSharedSerialPort(FUNCTION_BLACKBOX, FUNCTION_MSP);
    if (sharedBlackboxAndMspPort) {
        mspSerialReleasePortIfAllocated(sharedBlackboxAndMspPort);
    }
}
#endif // UNIT_TEST

void blackboxWrite(uint8_t value)
{
    switch (blackboxConfig()->device) {
#ifdef USE_FLASHFS
    case BLACKBOX_DEVICE_FLASH:
        flashfsWriteByte(value); // Write byte asynchronously
        break;
#endif
#ifdef USE_SDCARD
    case BLACKBOX_DEVICE_SDCARD:
        afatfs_fputc(blackboxSDCard.logFile, value);
        break;
#endif
    case BLACKBOX_DEVICE_SERIAL:
    default:
        serialWrite(blackboxPort, value);
        break;
    }
}

// Print the null-terminated string 's' to the blackbox device and return the number of bytes written
int blackboxPrint(const char *s)
{
    int length;
    const uint8_t *pos;

    switch (blackboxConfig()->device) {

#ifdef USE_FLASHFS
    case BLACKBOX_DEVICE_FLASH:
        length = strlen(s);
        flashfsWrite((const uint8_t*) s, length, false); // Write asynchronously
        break;
#endif

#ifdef USE_SDCARD
    case BLACKBOX_DEVICE_SDCARD:
        length = strlen(s);
        afatfs_fwrite(blackboxSDCard.logFile, (const uint8_t*) s, length); // Ignore failures due to buffers filling up
        break;
#endif

    case BLACKBOX_DEVICE_SERIAL:
    default:
        pos = (uint8_t*) s;
        while (*pos) {
            serialWrite(blackboxPort, *pos);
            pos++;
        }

        length = pos - (uint8_t*) s;
        break;
    }

    return length;
}

/**
 * If there is data waiting to be written to the blackbox device, attempt to write (a portion of) that now.
 *
 * Intended to be called regularly for the blackbox device to perform housekeeping.
 */
void blackboxDeviceFlush(void)
{
    switch (blackboxConfig()->device) {
#ifdef USE_FLASHFS
        /*
         * This is our only output device which requires us to call flush() in order for it to write anything. The other
         * devices will progressively write in the background without Blackbox calling anything.
         */
    case BLACKBOX_DEVICE_FLASH:
        flashfsFlushAsync();
        break;
#endif

    default:
        ;
    }
}

/**
 * If there is data waiting to be written to the blackbox device, attempt to write (a portion of) that now.
 *
 * Returns true if all data has been written to the device.
 */
bool blackboxDeviceFlushForce(void)
{
    switch (blackboxConfig()->device) {
    case BLACKBOX_DEVICE_SERIAL:
        // Nothing to speed up flushing on serial, as serial is continuously being drained out of its buffer
        return isSerialTransmitBufferEmpty(blackboxPort);

#ifdef USE_FLASHFS
    case BLACKBOX_DEVICE_FLASH:
        return flashfsFlushAsync();
#endif

#ifdef USE_SDCARD
    case BLACKBOX_DEVICE_SDCARD:
        /* SD card will flush itself without us calling it, but we need to call flush manually in order to check
         * if it's done yet or not!
         */
        return afatfs_flush();
#endif

    default:
        return false;
    }
}

/**
 * Attempt to open the logging device. Returns true if successful.
 */
#ifndef UNIT_TEST
bool blackboxDeviceOpen(void)
{
    switch (blackboxConfig()->device) {
    case BLACKBOX_DEVICE_SERIAL:
        {
            serialPortConfig_t *portConfig = findSerialPortConfig(FUNCTION_BLACKBOX);
            baudRate_e baudRateIndex;
            portOptions_t portOptions = SERIAL_PARITY_NO | SERIAL_NOT_INVERTED;

            if (!portConfig) {
                return false;
            }

            blackboxPortSharing = determinePortSharing(portConfig, FUNCTION_BLACKBOX);
            baudRateIndex = portConfig->peripheral_baudrateIndex;

            if (baudRates[baudRateIndex] == 230400) {
                /*
                 * OpenLog's 230400 baud rate is very inaccurate, so it requires a larger inter-character gap in
                 * order to maintain synchronization.
                 */
                portOptions |= SERIAL_STOPBITS_2;
            } else {
                portOptions |= SERIAL_STOPBITS_1;
            }

            blackboxPort = openSerialPort(portConfig->identifier, FUNCTION_BLACKBOX, NULL, NULL, baudRates[baudRateIndex],
                BLACKBOX_SERIAL_PORT_MODE, portOptions);

            /*
             * The slowest MicroSD cards have a write latency approaching 150ms. The OpenLog's buffer is about 900
             * bytes. In order for its buffer to be able to absorb this latency we must write slower than 6000 B/s.
             *
             * So:
             *     Bytes per loop iteration = floor((looptime_ns / 1000000.0) * 6000)
             *                              = floor((looptime_ns * 6000) / 1000000.0)
             *                              = floor((looptime_ns * 3) / 500.0)
             *                              = (looptime_ns * 3) / 500
             */
            blackboxMaxHeaderBytesPerIteration = constrain((gyro.targetLooptime * 3) / 500, 1, BLACKBOX_TARGET_HEADER_BUDGET_PER_ITERATION);

            return blackboxPort != NULL;
        }
        break;
#ifdef USE_FLASHFS
    case BLACKBOX_DEVICE_FLASH:
        if (flashfsGetSize() == 0 || isBlackboxDeviceFull()) {
            return false;
        }

        blackboxMaxHeaderBytesPerIteration = BLACKBOX_TARGET_HEADER_BUDGET_PER_ITERATION;

        return true;
        break;
#endif
#ifdef USE_SDCARD
    case BLACKBOX_DEVICE_SDCARD:
        if (afatfs_getFilesystemState() == AFATFS_FILESYSTEM_STATE_FATAL || afatfs_getFilesystemState() == AFATFS_FILESYSTEM_STATE_UNKNOWN || afatfs_isFull()) {
            return false;
        }

        blackboxMaxHeaderBytesPerIteration = BLACKBOX_TARGET_HEADER_BUDGET_PER_ITERATION;

        return true;
        break;
#endif
    default:
        return false;
    }
}
#endif // UNIT_TEST

/**
 * Close the Blackbox logging device immediately without attempting to flush any remaining data.
 */
#ifndef UNIT_TEST
void blackboxDeviceClose(void)
{
    switch (blackboxConfig()->device) {
    case BLACKBOX_DEVICE_SERIAL:
        // Since the serial port could be shared with other processes, we have to give it back here
        closeSerialPort(blackboxPort);
        blackboxPort = NULL;

        /*
         * Normally this would be handled by mw.c, but since we take an unknown amount
         * of time to shut down asynchronously, we're the only ones that know when to call it.
         */
        if (blackboxPortSharing == PORTSHARING_SHARED) {
            mspSerialAllocatePorts();
        }
        break;
    default:
        ;
    }
}
#endif // UNIT_TEST

#ifdef USE_SDCARD

static void blackboxLogDirCreated(afatfsFilePtr_t directory)
{
    if (directory) {
        blackboxSDCard.logDirectory = directory;

        afatfs_findFirst(blackboxSDCard.logDirectory, &blackboxSDCard.logDirectoryFinder);

        blackboxSDCard.state = BLACKBOX_SDCARD_ENUMERATE_FILES;
    } else {
        // Retry
        blackboxSDCard.state = BLACKBOX_SDCARD_INITIAL;
    }
}

static void blackboxLogFileCreated(afatfsFilePtr_t file)
{
    if (file) {
        blackboxSDCard.logFile = file;

        blackboxSDCard.largestLogFileNumber++;

        blackboxSDCard.state = BLACKBOX_SDCARD_READY_TO_LOG;
    } else {
        // Retry
        blackboxSDCard.state = BLACKBOX_SDCARD_READY_TO_CREATE_LOG;
    }
}

static void blackboxCreateLogFile(void)
{
    uint32_t remainder = blackboxSDCard.largestLogFileNumber + 1;

    char filename[13];

    filename[0] = 'L';
    filename[1] = 'O';
    filename[2] = 'G';

    for (int i = 7; i >= 3; i--) {
        filename[i] = (remainder % 10) + '0';
        remainder /= 10;
    }

    filename[8] = '.';
    filename[9] = 'T';
    filename[10] = 'X';
    filename[11] = 'T';
    filename[12] = 0;

    blackboxSDCard.state = BLACKBOX_SDCARD_WAITING;

    afatfs_fopen(filename, "as", blackboxLogFileCreated);
}

/**
 * Begin a new log on the SDCard.
 *
 * Keep calling until the function returns true (open is complete).
 */
static bool blackboxSDCardBeginLog(void)
{
    fatDirectoryEntry_t *directoryEntry;

    doMore:
    switch (blackboxSDCard.state) {
    case BLACKBOX_SDCARD_INITIAL:
        if (afatfs_getFilesystemState() == AFATFS_FILESYSTEM_STATE_READY) {
            blackboxSDCard.state = BLACKBOX_SDCARD_WAITING;

            afatfs_mkdir("logs", blackboxLogDirCreated);
        }
        break;

    case BLACKBOX_SDCARD_WAITING:
        // Waiting for directory entry to be created
        break;

    case BLACKBOX_SDCARD_ENUMERATE_FILES:
        while (afatfs_findNext(blackboxSDCard.logDirectory, &blackboxSDCard.logDirectoryFinder, &directoryEntry) == AFATFS_OPERATION_SUCCESS) {
            if (directoryEntry && !fat_isDirectoryEntryTerminator(directoryEntry)) {
                // If this is a log file, parse the log number from the filename
                if (
                    directoryEntry->filename[0] == 'L' && directoryEntry->filename[1] == 'O' && directoryEntry->filename[2] == 'G'
                    && directoryEntry->filename[8] == 'T' && directoryEntry->filename[9] == 'X' && directoryEntry->filename[10] == 'T'
                ) {
                    char logSequenceNumberString[6];

                    memcpy(logSequenceNumberString, directoryEntry->filename + 3, 5);
                    logSequenceNumberString[5] = '\0';

                    blackboxSDCard.largestLogFileNumber = MAX((uint32_t) fastA2I(logSequenceNumberString), blackboxSDCard.largestLogFileNumber);
                }
            } else {
                // We're done checking all the files on the card, now we can create a new log file
                afatfs_findLast(blackboxSDCard.logDirectory);

                blackboxSDCard.state = BLACKBOX_SDCARD_CHANGE_INTO_LOG_DIRECTORY;
                goto doMore;
            }
        }
        break;

    case BLACKBOX_SDCARD_CHANGE_INTO_LOG_DIRECTORY:
        // Change into the log directory:
        if (afatfs_chdir(blackboxSDCard.logDirectory)) {
            // We no longer need our open handle on the log directory
            afatfs_fclose(blackboxSDCard.logDirectory, NULL);
            blackboxSDCard.logDirectory = NULL;

            blackboxSDCard.state = BLACKBOX_SDCARD_READY_TO_CREATE_LOG;
            goto doMore;
        }
        break;

    case BLACKBOX_SDCARD_READY_TO_CREATE_LOG:
        blackboxCreateLogFile();
        break;

    case BLACKBOX_SDCARD_READY_TO_LOG:
        return true; // Log has been created!
    }

    // Not finished init yet
    return false;
}

#endif

/**
 * Begin a new log (for devices which support separations between the logs of multiple flights).
 *
 * Keep calling until the function returns true (open is complete).
 */
bool blackboxDeviceBeginLog(void)
{
    switch (blackboxConfig()->device) {
#ifdef USE_SDCARD
    case BLACKBOX_DEVICE_SDCARD:
        return blackboxSDCardBeginLog();
#endif
    default:
        return true;
    }

}

/**
 * Terminate the current log (for devices which support separations between the logs of multiple flights).
 *
 * retainLog - Pass true if the log should be kept, or false if the log should be discarded (if supported).
 *
 * Keep calling until this returns true
 */
bool blackboxDeviceEndLog(bool retainLog)
{
#ifndef USE_SDCARD
    (void) retainLog;
#endif

    switch (blackboxConfig()->device) {
#ifdef USE_SDCARD
    case BLACKBOX_DEVICE_SDCARD:
        // Keep retrying until the close operation queues
        if (
            (retainLog && afatfs_fclose(blackboxSDCard.logFile, NULL))
            || (!retainLog && afatfs_funlink(blackboxSDCard.logFile, NULL))
        ) {
            // Don't bother waiting the for the close to complete, it's queued now and will complete eventually
            blackboxSDCard.logFile = NULL;
            blackboxSDCard.state = BLACKBOX_SDCARD_READY_TO_CREATE_LOG;
            return true;
        }
        return false;
#endif
    default:
        return true;
    }
}

bool isBlackboxDeviceFull(void)
{
    switch (blackboxConfig()->device) {
    case BLACKBOX_DEVICE_SERIAL:
        return false;

#ifdef USE_FLASHFS
    case BLACKBOX_DEVICE_FLASH:
        return flashfsIsEOF();
#endif

#ifdef USE_SDCARD
    case BLACKBOX_DEVICE_SDCARD:
        return afatfs_isFull();
#endif

    default:
        return false;
    }
}

/**
 * Call once every loop iteration in order to maintain the global blackboxHeaderBudget with the number of bytes we can
 * transmit this iteration.
 */
void blackboxReplenishHeaderBudget(void)
{
    int32_t freeSpace;

    switch (blackboxConfig()->device) {
    case BLACKBOX_DEVICE_SERIAL:
        freeSpace = serialTxBytesFree(blackboxPort);
        break;
#ifdef USE_FLASHFS
    case BLACKBOX_DEVICE_FLASH:
        freeSpace = flashfsGetWriteBufferFreeSpace();
        break;
#endif
#ifdef USE_SDCARD
    case BLACKBOX_DEVICE_SDCARD:
        freeSpace = afatfs_getFreeBufferSpace();
        break;
#endif
    default:
        freeSpace = 0;
    }

    blackboxHeaderBudget = MIN(MIN(freeSpace, blackboxHeaderBudget + blackboxMaxHeaderBytesPerIteration), BLACKBOX_MAX_ACCUMULATED_HEADER_BUDGET);
}

/**
 * You must call this function before attempting to write Blackbox header bytes to ensure that the write will not
 * cause buffers to overflow. The number of bytes you can write is capped by the blackboxHeaderBudget. Calling this
 * reservation function doesn't decrease blackboxHeaderBudget, so you must manually decrement that variable by the
 * number of bytes you actually wrote.
 *
 * When the Blackbox device is FlashFS, a successful return code guarantees that no data will be lost if you write that
 * many bytes to the device (i.e. FlashFS's buffers won't overflow).
 *
 * When the device is a serial port, a successful return code guarantees that Cleanflight's serial Tx buffer will not
 * overflow, and the outgoing bandwidth is likely to be small enough to give the OpenLog time to absorb MicroSD card
 * latency. However the OpenLog could still end up silently dropping data.
 *
 * Returns:
 *  BLACKBOX_RESERVE_SUCCESS - Upon success
 *  BLACKBOX_RESERVE_TEMPORARY_FAILURE - The buffer is currently too full to service the request, try again later
 *  BLACKBOX_RESERVE_PERMANENT_FAILURE - The buffer is too small to ever service this request
 */
blackboxBufferReserveStatus_e blackboxDeviceReserveBufferSpace(int32_t bytes)
{
    if (bytes <= blackboxHeaderBudget) {
        return BLACKBOX_RESERVE_SUCCESS;
    }

    // Handle failure:
    switch (blackboxConfig()->device) {
    case BLACKBOX_DEVICE_SERIAL:
        /*
         * One byte of the tx buffer isn't available for user data (due to its circular list implementation),
         * hence the -1. Note that the USB VCP implementation doesn't use a buffer and has txBufferSize set to zero.
         */
        if (blackboxPort->txBufferSize && bytes > (int32_t) blackboxPort->txBufferSize - 1) {
            return BLACKBOX_RESERVE_PERMANENT_FAILURE;
        }

        return BLACKBOX_RESERVE_TEMPORARY_FAILURE;

#ifdef USE_FLASHFS
    case BLACKBOX_DEVICE_FLASH:
        if (bytes > (int32_t) flashfsGetWriteBufferSize()) {
            return BLACKBOX_RESERVE_PERMANENT_FAILURE;
        }

        if (bytes > (int32_t) flashfsGetWriteBufferFreeSpace()) {
            /*
             * The write doesn't currently fit in the buffer, so try to make room for it. Our flushing here means
             * that the Blackbox header writing code doesn't have to guess about the best time to ask flashfs to
             * flush, and doesn't stall waiting for a flush that would otherwise not automatically be called.
             */
            flashfsFlushAsync();
        }

        return BLACKBOX_RESERVE_TEMPORARY_FAILURE;
#endif

#ifdef USE_SDCARD
    case BLACKBOX_DEVICE_SDCARD:
        // Assume that all writes will fit in the SDCard's buffers
        return BLACKBOX_RESERVE_TEMPORARY_FAILURE;
#endif

    default:
        return BLACKBOX_RESERVE_PERMANENT_FAILURE;
    }
}

#endif