//-----------------------------------------------------------------------------
// Jonathan Westhues, April 2006
// iZsh <izsh at fail0verflow.com>, 2014
//
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
// at your option, any later version. See the LICENSE.txt file for the text of
// the license.
//-----------------------------------------------------------------------------
// Routines to load the FPGA image, and then to configure the FPGA's major
// mode once it is configured.
//-----------------------------------------------------------------------------
#include "fpgaloader.h"


// remember which version of the bitstream we have already downloaded to the FPGA
static int downloaded_bitstream = 0;

// this is where the bitstreams are located in memory:
extern uint8_t _binary_obj_fpga_all_bit_z_start, _binary_obj_fpga_all_bit_z_end;

static uint8_t *fpga_image_ptr = NULL;
static uint32_t uncompressed_bytes_cnt;

#define OUTPUT_BUFFER_LEN 80

//-----------------------------------------------------------------------------
// Set up the Serial Peripheral Interface as master
// Used to write the FPGA config word
// May also be used to write to other SPI attached devices like an LCD
//-----------------------------------------------------------------------------
static void DisableSpi(void) {
    //* Reset all the Chip Select register
    AT91C_BASE_SPI->SPI_CSR[0] = 0;
    AT91C_BASE_SPI->SPI_CSR[1] = 0;
    AT91C_BASE_SPI->SPI_CSR[2] = 0;
    AT91C_BASE_SPI->SPI_CSR[3] = 0;

    // Reset the SPI mode
    AT91C_BASE_SPI->SPI_MR = 0;

    // Disable all interrupts
    AT91C_BASE_SPI->SPI_IDR = 0xFFFFFFFF;

    // SPI disable
    AT91C_BASE_SPI->SPI_CR = AT91C_SPI_SPIDIS;
}

void SetupSpi(int mode) {
    // PA1  -> SPI_NCS3 chip select (MEM)
    // PA10 -> SPI_NCS2 chip select (LCD)
    // PA11 -> SPI_NCS0 chip select (FPGA)
    // PA12 -> SPI_MISO Master-In Slave-Out
    // PA13 -> SPI_MOSI Master-Out Slave-In
    // PA14 -> SPI_SPCK Serial Clock

    // Disable PIO control of the following pins, allows use by the SPI peripheral
    AT91C_BASE_PIOA->PIO_PDR = GPIO_NCS0 | GPIO_MISO | GPIO_MOSI | GPIO_SPCK;

    // Peripheral A
    AT91C_BASE_PIOA->PIO_ASR = GPIO_NCS0 | GPIO_MISO | GPIO_MOSI | GPIO_SPCK;

    // Peripheral B
    //AT91C_BASE_PIOA->PIO_BSR |= GPIO_NCS2;

    //enable the SPI Peripheral clock
    AT91C_BASE_PMC->PMC_PCER = (1 << AT91C_ID_SPI);
    // Enable SPI
    AT91C_BASE_SPI->SPI_CR = AT91C_SPI_SPIEN;

    switch (mode) {
        case SPI_FPGA_MODE:
            AT91C_BASE_SPI->SPI_MR =
                (0 << 24)          |  // Delay between chip selects (take default: 6 MCK periods)
                (0xE << 16)         | // Peripheral Chip Select (selects FPGA SPI_NCS0 or PA11)
                (0 << 7)           |  // Local Loopback Disabled
                AT91C_SPI_MODFDIS   | // Mode Fault Detection disabled
                (0 << 2)           |  // Chip selects connected directly to peripheral
                AT91C_SPI_PS_FIXED  | // Fixed Peripheral Select
                AT91C_SPI_MSTR;       // Master Mode

            AT91C_BASE_SPI->SPI_CSR[0] =
                (1 << 24)          |  // Delay between Consecutive Transfers (32 MCK periods)
                (1 << 16)          |  // Delay Before SPCK (1 MCK period)
                (6 << 8)           |  // Serial Clock Baud Rate (baudrate = MCK/6 = 24Mhz/6 = 4M baud
                AT91C_SPI_BITS_16   | // Bits per Transfer (16 bits)
                (0 << 3)           |  // Chip Select inactive after transfer
                AT91C_SPI_NCPHA     | // Clock Phase data captured on leading edge, changes on following edge
                (0 << 0);             // Clock Polarity inactive state is logic 0
            break;
        /*
                    case SPI_LCD_MODE:
                    AT91C_BASE_SPI->SPI_MR =
                        ( 0 << 24)          | // Delay between chip selects (take default: 6 MCK periods)
                        (0xB << 16)         | // Peripheral Chip Select (selects LCD SPI_NCS2 or PA10)
                        ( 0 << 7)           | // Local Loopback Disabled
                        ( 1 << 4)           | // Mode Fault Detection disabled
                        ( 0 << 2)           | // Chip selects connected directly to peripheral
                        ( 0 << 1)           | // Fixed Peripheral Select
                        ( 1 << 0);            // Master Mode

                    AT91C_BASE_SPI->SPI_CSR[2] =
                        ( 1 << 24)          | // Delay between Consecutive Transfers (32 MCK periods)
                        ( 1 << 16)          | // Delay Before SPCK (1 MCK period)
                        ( 6 << 8)           | // Serial Clock Baud Rate (baudrate = MCK/6 = 24Mhz/6 = 4M baud
                        AT91C_SPI_BITS_9    | // Bits per Transfer (9 bits)
                        ( 0 << 3)           | // Chip Select inactive after transfer
                        ( 1 << 1)           | // Clock Phase data captured on leading edge, changes on following edge
                        ( 0 << 0);            // Clock Polarity inactive state is logic 0
                    break;
        */
        default:
            DisableSpi();
            break;
    }
}

//-----------------------------------------------------------------------------
// Set up the synchronous serial port, with the one set of options that we
// always use when we are talking to the FPGA. Both RX and TX are enabled.
//-----------------------------------------------------------------------------
void FpgaSetupSsc(void) {
    // First configure the GPIOs, and get ourselves a clock.
    AT91C_BASE_PIOA->PIO_ASR =
        GPIO_SSC_FRAME  |
        GPIO_SSC_DIN    |
        GPIO_SSC_DOUT   |
        GPIO_SSC_CLK;
    AT91C_BASE_PIOA->PIO_PDR = GPIO_SSC_DOUT;

    AT91C_BASE_PMC->PMC_PCER = (1 << AT91C_ID_SSC);

    // Now set up the SSC proper, starting from a known state.
    AT91C_BASE_SSC->SSC_CR = AT91C_SSC_SWRST;

    // RX clock comes from TX clock, RX starts when TX starts, data changes
    // on RX clock rising edge, sampled on falling edge
    AT91C_BASE_SSC->SSC_RCMR = SSC_CLOCK_MODE_SELECT(1) | SSC_CLOCK_MODE_START(1);

    // 8 bits per transfer, no loopback, MSB first, 1 transfer per sync
    // pulse, no output sync
    AT91C_BASE_SSC->SSC_RFMR = SSC_FRAME_MODE_BITS_IN_WORD(8) | AT91C_SSC_MSBF | SSC_FRAME_MODE_WORDS_PER_TRANSFER(0);

    // clock comes from TK pin, no clock output, outputs change on falling
    // edge of TK, sample on rising edge of TK, start on positive-going edge of sync
    AT91C_BASE_SSC->SSC_TCMR = SSC_CLOCK_MODE_SELECT(2) | SSC_CLOCK_MODE_START(5);

    // tx framing is the same as the rx framing
    AT91C_BASE_SSC->SSC_TFMR = AT91C_BASE_SSC->SSC_RFMR;

    AT91C_BASE_SSC->SSC_CR = AT91C_SSC_RXEN | AT91C_SSC_TXEN;
}

//-----------------------------------------------------------------------------
// Set up DMA to receive samples from the FPGA. We will use the PDC, with
// a single buffer as a circular buffer (so that we just chain back to
// ourselves, not to another buffer). The stuff to manipulate those buffers
// is in apps.h, because it should be inlined, for speed.
//-----------------------------------------------------------------------------
bool FpgaSetupSscDma(uint8_t *buf, int len) {
    if (buf == NULL) return false;

    FpgaDisableSscDma();
    AT91C_BASE_PDC_SSC->PDC_RPR = (uint32_t) buf;  // transfer to this memory address
    AT91C_BASE_PDC_SSC->PDC_RCR = len;             // transfer this many bytes
    AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) buf; // next transfer to same memory address
    AT91C_BASE_PDC_SSC->PDC_RNCR = len;            // ... with same number of bytes
    FpgaEnableSscDma();
    return true;
}

//----------------------------------------------------------------------------
// Uncompress (inflate) the FPGA data. Returns one decompressed byte with
// each call.
//----------------------------------------------------------------------------
static int get_from_fpga_combined_stream(z_streamp compressed_fpga_stream, uint8_t *output_buffer) {
    if (fpga_image_ptr == compressed_fpga_stream->next_out) { // need more data
        compressed_fpga_stream->next_out = output_buffer;
        compressed_fpga_stream->avail_out = OUTPUT_BUFFER_LEN;
        fpga_image_ptr = output_buffer;
        int res = inflate(compressed_fpga_stream, Z_SYNC_FLUSH);

        if (res != Z_OK)
            Dbprintf("inflate returned: %d, %s", res, compressed_fpga_stream->msg);

        if (res < 0)
            return res;
    }
    uncompressed_bytes_cnt++;
    return *fpga_image_ptr++;
}

//----------------------------------------------------------------------------
// Undo the interleaving of several FPGA config files. FPGA config files
// are combined into one big file:
// 288 bytes from FPGA file 1, followed by 288 bytes from FGPA file 2, etc.
//----------------------------------------------------------------------------
static int get_from_fpga_stream(int bitstream_version, z_streamp compressed_fpga_stream, uint8_t *output_buffer) {
    while ((uncompressed_bytes_cnt / FPGA_INTERLEAVE_SIZE) % fpga_bitstream_num != (bitstream_version - 1)) {
        // skip undesired data belonging to other bitstream_versions
        get_from_fpga_combined_stream(compressed_fpga_stream, output_buffer);
    }

    return get_from_fpga_combined_stream(compressed_fpga_stream, output_buffer);
}

static voidpf fpga_inflate_malloc(voidpf opaque, uInt items, uInt size) {
    return BigBuf_malloc(items * size);
}

// free eventually allocated BigBuf memory
static void fpga_inflate_free(voidpf opaque, voidpf address) {
    BigBuf_free();
    BigBuf_Clear_ext(false);
}

//----------------------------------------------------------------------------
// Initialize decompression of the respective (HF or LF) FPGA stream
//----------------------------------------------------------------------------
static bool reset_fpga_stream(int bitstream_version, z_streamp compressed_fpga_stream, uint8_t *output_buffer) {
    uint8_t header[FPGA_BITSTREAM_FIXED_HEADER_SIZE];

    uncompressed_bytes_cnt = 0;

    // initialize z_stream structure for inflate:
    compressed_fpga_stream->next_in = &_binary_obj_fpga_all_bit_z_start;
    compressed_fpga_stream->avail_in = &_binary_obj_fpga_all_bit_z_end - &_binary_obj_fpga_all_bit_z_start;
    compressed_fpga_stream->next_out = output_buffer;
    compressed_fpga_stream->avail_out = OUTPUT_BUFFER_LEN;
    compressed_fpga_stream->zalloc = &fpga_inflate_malloc;
    compressed_fpga_stream->zfree = &fpga_inflate_free;

    int res = inflateInit2(compressed_fpga_stream, 0);
    if (res < 0)
        return false;

    fpga_image_ptr = output_buffer;

    for (uint16_t i = 0; i < FPGA_BITSTREAM_FIXED_HEADER_SIZE; i++)
        header[i] = get_from_fpga_stream(bitstream_version, compressed_fpga_stream, output_buffer);

    // Check for a valid .bit file (starts with bitparse_fixed_header)
    if (memcmp(bitparse_fixed_header, header, FPGA_BITSTREAM_FIXED_HEADER_SIZE) == 0)
        return true;

    return false;
}

static void DownloadFPGA_byte(uint8_t w) {
#define SEND_BIT(x) { if(w & (1<<x) ) HIGH(GPIO_FPGA_DIN); else LOW(GPIO_FPGA_DIN); HIGH(GPIO_FPGA_CCLK); LOW(GPIO_FPGA_CCLK); }
    SEND_BIT(7);
    SEND_BIT(6);
    SEND_BIT(5);
    SEND_BIT(4);
    SEND_BIT(3);
    SEND_BIT(2);
    SEND_BIT(1);
    SEND_BIT(0);
}

// Download the fpga image starting at current stream position with length FpgaImageLen bytes
static void DownloadFPGA(int bitstream_version, int FpgaImageLen, z_streamp compressed_fpga_stream, uint8_t *output_buffer) {
    int i = 0;

    AT91C_BASE_PIOA->PIO_OER = GPIO_FPGA_ON;
    AT91C_BASE_PIOA->PIO_PER = GPIO_FPGA_ON;
    HIGH(GPIO_FPGA_ON);  // ensure everything is powered on

    SpinDelay(50);

    LED_D_ON();

    // These pins are inputs
    AT91C_BASE_PIOA->PIO_ODR =
        GPIO_FPGA_NINIT |
        GPIO_FPGA_DONE;
    // PIO controls the following pins
    AT91C_BASE_PIOA->PIO_PER =
        GPIO_FPGA_NINIT |
        GPIO_FPGA_DONE;
    // Enable pull-ups
    AT91C_BASE_PIOA->PIO_PPUER =
        GPIO_FPGA_NINIT |
        GPIO_FPGA_DONE;

    // setup initial logic state
    HIGH(GPIO_FPGA_NPROGRAM);
    LOW(GPIO_FPGA_CCLK);
    LOW(GPIO_FPGA_DIN);
    // These pins are outputs
    AT91C_BASE_PIOA->PIO_OER =
        GPIO_FPGA_NPROGRAM |
        GPIO_FPGA_CCLK     |
        GPIO_FPGA_DIN;

    // enter FPGA configuration mode
    LOW(GPIO_FPGA_NPROGRAM);
    SpinDelay(50);
    HIGH(GPIO_FPGA_NPROGRAM);

    i = 100000;
    // wait for FPGA ready to accept data signal
    while ((i) && (!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_FPGA_NINIT))) {
        i--;
    }

    // crude error indicator, leave both red LEDs on and return
    if (i == 0) {
        LED_C_ON();
        LED_D_ON();
        return;
    }

    for (i = 0; i < FpgaImageLen; i++) {
        int b = get_from_fpga_stream(bitstream_version, compressed_fpga_stream, output_buffer);
        if (b < 0) {
            Dbprintf("Error %d during FpgaDownload", b);
            break;
        }
        DownloadFPGA_byte(b);
    }

    // continue to clock FPGA until ready signal goes high
    i = 100000;
    while ((i--) && (!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_FPGA_DONE))) {
        HIGH(GPIO_FPGA_CCLK);
        LOW(GPIO_FPGA_CCLK);
    }
    // crude error indicator, leave both red LEDs on and return
    if (i == 0) {
        LED_C_ON();
        LED_D_ON();
        return;
    }
    LED_D_OFF();
}

/* Simple Xilinx .bit parser. The file starts with the fixed opaque byte sequence
 * 00 09 0f f0 0f f0 0f f0 0f f0 00 00 01
 * After that the format is 1 byte section type (ASCII character), 2 byte length
 * (big endian), <length> bytes content. Except for section 'e' which has 4 bytes
 * length.
 */
static int bitparse_find_section(int bitstream_version, char section_name, uint32_t *section_length, z_streamp compressed_fpga_stream, uint8_t *output_buffer) {
    int result = 0;
#define MAX_FPGA_BIT_STREAM_HEADER_SEARCH 100  // maximum number of bytes to search for the requested section
    uint16_t numbytes = 0;
    while (numbytes < MAX_FPGA_BIT_STREAM_HEADER_SEARCH) {
        char current_name = get_from_fpga_stream(bitstream_version, compressed_fpga_stream, output_buffer);
        numbytes++;
        uint32_t current_length = 0;
        if (current_name < 'a' || current_name > 'e') {
            /* Strange section name, abort */
            break;
        }
        current_length = 0;
        switch (current_name) {
            case 'e':
                /* Four byte length field */
                current_length += get_from_fpga_stream(bitstream_version, compressed_fpga_stream, output_buffer) << 24;
                current_length += get_from_fpga_stream(bitstream_version, compressed_fpga_stream, output_buffer) << 16;
                numbytes += 2;
            default: /* Fall through, two byte length field */
                current_length += get_from_fpga_stream(bitstream_version, compressed_fpga_stream, output_buffer) << 8;
                current_length += get_from_fpga_stream(bitstream_version, compressed_fpga_stream, output_buffer) << 0;
                numbytes += 2;
        }

        if (current_name != 'e' && current_length > 255) {
            /* Maybe a parse error */
            break;
        }

        if (current_name == section_name) {
            /* Found it */
            *section_length = current_length;
            result = 1;
            break;
        }

        for (uint16_t i = 0; i < current_length && numbytes < MAX_FPGA_BIT_STREAM_HEADER_SEARCH; i++) {
            get_from_fpga_stream(bitstream_version, compressed_fpga_stream, output_buffer);
            numbytes++;
        }
    }
    return result;
}

//----------------------------------------------------------------------------
// Check which FPGA image is currently loaded (if any). If necessary
// decompress and load the correct (HF or LF) image to the FPGA
//----------------------------------------------------------------------------
void FpgaDownloadAndGo(int bitstream_version) {

    // check whether or not the bitstream is already loaded
    if (downloaded_bitstream == bitstream_version)
        return;

    z_stream compressed_fpga_stream;
    uint8_t output_buffer[OUTPUT_BUFFER_LEN] = {0x00};

    bool verbose = (MF_DBGLEVEL > 3);

    // make sure that we have enough memory to decompress
    BigBuf_free();
    BigBuf_Clear_ext(verbose);

    if (!reset_fpga_stream(bitstream_version, &compressed_fpga_stream, output_buffer))
        return;

    uint32_t bitstream_length;
    if (bitparse_find_section(bitstream_version, 'e', &bitstream_length, &compressed_fpga_stream, output_buffer)) {
        DownloadFPGA(bitstream_version, bitstream_length, &compressed_fpga_stream, output_buffer);
        downloaded_bitstream = bitstream_version;
    }

    inflateEnd(&compressed_fpga_stream);

    // turn off antenna
    FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

    // free eventually allocated BigBuf memory
    BigBuf_free();
    BigBuf_Clear_ext(false);
}

//-----------------------------------------------------------------------------
// Send a 16 bit command/data pair to the FPGA.
// The bit format is:  C3 C2 C1 C0 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
// where C is the 4 bit command and D is the 12 bit data
//-----------------------------------------------------------------------------
void FpgaSendCommand(uint16_t cmd, uint16_t v) {
    SetupSpi(SPI_FPGA_MODE);
    while ((AT91C_BASE_SPI->SPI_SR & AT91C_SPI_TXEMPTY) == 0); // wait for the transfer to complete
    AT91C_BASE_SPI->SPI_TDR = AT91C_SPI_LASTXFER | cmd | v;    // send the data
    while (!(AT91C_BASE_SPI->SPI_SR & AT91C_SPI_RDRF)) {};     // wait till transfer is complete
}
//-----------------------------------------------------------------------------
// Write the FPGA setup word (that determines what mode the logic is in, read
// vs. clone vs. etc.). This is now a special case of FpgaSendCommand() to
// avoid changing this function's occurence everywhere in the source code.
//-----------------------------------------------------------------------------
void FpgaWriteConfWord(uint8_t v) {
    FpgaSendCommand(FPGA_CMD_SET_CONFREG, v);
}

//-----------------------------------------------------------------------------
// Set up the CMOS switches that mux the ADC: four switches, independently
// closable, but should only close one at a time. Not an FPGA thing, but
// the samples from the ADC always flow through the FPGA.
//-----------------------------------------------------------------------------
void SetAdcMuxFor(uint32_t whichGpio) {

#ifndef WITH_FPC
    // When compiled without FPC support
    AT91C_BASE_PIOA->PIO_OER =
        GPIO_MUXSEL_HIPKD |
        GPIO_MUXSEL_LOPKD |
        GPIO_MUXSEL_LORAW |
        GPIO_MUXSEL_HIRAW;

    AT91C_BASE_PIOA->PIO_PER =
        GPIO_MUXSEL_HIPKD |
        GPIO_MUXSEL_LOPKD |
        GPIO_MUXSEL_LORAW |
        GPIO_MUXSEL_HIRAW;

    LOW(GPIO_MUXSEL_HIPKD);
    LOW(GPIO_MUXSEL_LOPKD);
    LOW(GPIO_MUXSEL_HIRAW);
    LOW(GPIO_MUXSEL_LORAW);

#else
    // FPC serial uses HIRAW/LOWRAW pins, so they are excluded here.
    AT91C_BASE_PIOA->PIO_OER = GPIO_MUXSEL_HIPKD | GPIO_MUXSEL_LOPKD;
    AT91C_BASE_PIOA->PIO_PER = GPIO_MUXSEL_HIPKD | GPIO_MUXSEL_LOPKD;
    LOW(GPIO_MUXSEL_HIPKD);
    LOW(GPIO_MUXSEL_LOPKD);
#endif

    HIGH(whichGpio);
}

void Fpga_print_status(void) {
    Dbprintf("Currently loaded FPGA image");
    Dbprintf("  mode....................%s", fpga_version_information[downloaded_bitstream - 1]);
}

int FpgaGetCurrent(void) {
    return downloaded_bitstream;
}

// Turns off the antenna,
// log message
// if HF,  Disable SSC DMA
// turn off trace and leds off.
void switch_off(void) {
    if (MF_DBGLEVEL > 3) Dbprintf("switch_off");
    FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
    if (downloaded_bitstream == FPGA_BITSTREAM_HF)
        FpgaDisableSscDma();
    set_tracing(false);
    LEDsoff();
}