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#include "../ns_pdm.h"
#include "am_bsp.h"
#include "am_mcu_apollo.h"
#include "am_util.h"
#include "ns_audio.h"
#include "ns_core.h"

static void *pvPDMHandle;

#ifdef NS_PDM1TO3_PRESENT
static const IRQn_Type g_ePdmInterrupts[] = {PDM0_IRQn, PDM1_IRQn, PDM2_IRQn, PDM3_IRQn};
#else
static const IRQn_Type g_ePdmInterrupts[] = {PDM0_IRQn};
#endif

ns_pdm_cfg_t ns_pdm_default = {
    .clock = NS_CLKSEL_PLL,
    .clock_freq = NS_AUDIO_PDM_CLK_750KHZ,
    .mic = NS_AUDIO_PDM_MICBOARD_0,
    .numBytes = NS_AUDIO_PDM_SAMPLE_16BIT,
    .left_gain = AM_HAL_PDM_GAIN_0DB,
    .right_gain = AM_HAL_PDM_GAIN_0DB,
};

void pdm_trigger_dma(ns_audio_config_t *config) {

    // Configure DMA and target address.
    config->sTransfer.ui32TotalCount =
        (config->numSamples * config->numChannels * config->pdm_config->numBytes * 2);
    config->sTransfer.ui32TargetAddr = (uint32_t)(((uint32_t)config->sampleBuffer + 3) & ~0xF);
    config->sTransfer.ui32TargetAddrReverse =
        config->sTransfer.ui32TargetAddr + config->sTransfer.ui32TotalCount;

    // Start the data transfer.
    am_hal_pdm_dma_start(pvPDMHandle, &(config->sTransfer));
}

uint32_t pdm_init(ns_audio_config_t *config) {
    ns_pdm_cfg_t *cfg = config->pdm_config;

    // Common PDM Configuration
    am_hal_pdm_config_t pdmConfig = {
        .eStepSize = AM_HAL_PDM_GAIN_STEP_0_13DB,
        .bHighPassEnable = AM_HAL_PDM_HIGH_PASS_ENABLE,
        .ui32HighPassCutoff = 0x3,
        .eLeftGain = AM_HAL_PDM_GAIN_0DB,
        .eRightGain = AM_HAL_PDM_GAIN_0DB,
        .bDataPacking = 1,
        .bPDMSampleDelay = AM_HAL_PDM_CLKOUT_PHSDLY_NONE,
        .ui32GainChangeDelay = AM_HAL_PDM_CLKOUT_DELAY_NONE,
        .bSoftMute = 0,
        .bLRSwap = 0,
    };
    // PDM Gain Config
    pdmConfig.eLeftGain = cfg->left_gain;
    pdmConfig.eRightGain = cfg->right_gain;
    // am_hal_pdm_config_t g_sPdmConfig =
    // {
    //     //
    //     // Example setting:
    //     //  1.536 MHz PDM CLK OUT:
    //     //      PDM_CLK_OUT = ePDMClkSpeed / (eClkDivider + 1) / (ePDMAClkOutDivder + 1)
    //     //  16 kHz 24bit Sampling:
    //     //      DecimationRate = 48
    //     //      SAMPLEING_FREQ = PDM_CLK_OUT / (ui32DecimationRate * 2)
    //     //
    //     #if (CLOCK_SOURCE == HFRC)
    //         .eClkDivider         = AM_HAL_PDM_MCLKDIV_1,
    //         .ePDMAClkOutDivder   = AM_HAL_PDM_PDMA_CLKO_DIV7,
    //         .ePDMClkSpeed        = AM_HAL_PDM_CLK_HFRC_24MHZ,
    //     #elif (CLOCK_SOURCE == PLL)
    //         // .eClkDivider         = AM_HAL_PDM_MCLKDIV_1,
    //         // .ePDMAClkOutDivder   = AM_HAL_PDM_PDMA_CLKO_DIV3,
    //         // .ePDMClkSpeed        = AM_HAL_PDM_CLK_PLL,
    //     #elif (CLOCK_SOURCE == HF2ADJ)
    //         .eClkDivider         = AM_HAL_PDM_MCLKDIV_1,

    //         #if defined(AM_PART_APOLLO5A)
    //             .ePDMAClkOutDivder   = AM_HAL_PDM_PDMA_CLKO_DIV15,
    //         #elif defined(AM_PART_APOLLO5B)
    //             .ePDMAClkOutDivder   = AM_HAL_PDM_PDMA_CLKO_DIV7,
    //         #endif

    //         .ePDMClkSpeed        = AM_HAL_PDM_CLK_HFRC2_31MHZ,
    //     #endif
    //     // .ui32DecimationRate  = 48,
    //     // .eLeftGain           = AM_HAL_PDM_GAIN_0DB,
    //     // .eRightGain          = AM_HAL_PDM_GAIN_0DB,
    //     // .eStepSize           = AM_HAL_PDM_GAIN_STEP_0_13DB,
    //     // .bHighPassEnable     = AM_HAL_PDM_HIGH_PASS_ENABLE,
    //     // .ui32HighPassCutoff  = 0x3,
    //     // .bDataPacking        = 1,
    //     // .ePCMChannels        = AM_HAL_PDM_CHANNEL_LEFT,
    //     // .bPDMSampleDelay     = AM_HAL_PDM_CLKOUT_PHSDLY_NONE,
    //     // .ui32GainChangeDelay = AM_HAL_PDM_CLKOUT_DELAY_NONE,
    //     // .bSoftMute           = 0,
    //     // .bLRSwap             = 0,
    // };
    // ns_lp_printf("PDM Init clock src %d\n", cfg->clock);

    // PDM Clock Config
    switch (cfg->clock) {
    case NS_CLKSEL_PLL:
        pdmConfig.ePDMClkSpeed = AM_HAL_PDM_CLK_PLL;
        pdmConfig.eClkDivider = AM_HAL_PDM_MCLKDIV_1;
        break;
    case NS_CLKSEL_HFRC:
        pdmConfig.ePDMClkSpeed = AM_HAL_PDM_CLK_HFRC_24MHZ;
        pdmConfig.eClkDivider = AM_HAL_PDM_MCLKDIV_1;
        // if (cfg->clock_freq == NS_AUDIO_PDM_CLK_750KHZ) {
        //     pdmConfig.ePDMAClkOutDivder = AM_HAL_PDM_PDMA_CLKO_DIV15;
        //     pdmConfig.ui32DecimationRate = 24;
        // } else {
        //     pdmConfig.ePDMAClkOutDivder = AM_HAL_PDM_PDMA_CLKO_DIV7;
        //     pdmConfig.ui32DecimationRate = 48;
        // }
        break;
    case NS_CLKSEL_HFRC2_ADJ:
        pdmConfig.ePDMClkSpeed = AM_HAL_PDM_CLK_HFRC2_31MHZ;
        pdmConfig.eClkDivider = AM_HAL_PDM_MCLKDIV_1;
        break;
    case NS_CLKSEL_HFXTAL:
        pdmConfig.ePDMClkSpeed = AM_HAL_PDM_CLK_HFXTAL;
        pdmConfig.eClkDivider = AM_HAL_PDM_MCLKDIV_3;
        break;
    case NS_CLKSEL_XTHS:
    case NS_CLKSEL_HFRC2:
        ns_lp_printf("Clock not supported by PDM\n");
        return NS_STATUS_INVALID_CONFIG;
    }

    // PDM Frequency Config
    if ((cfg->clock == NS_CLKSEL_HFRC2_ADJ) || (cfg->clock == NS_CLKSEL_HFRC)) {
        switch (cfg->clock_freq) {
        case NS_AUDIO_PDM_CLK_750KHZ:
            pdmConfig.ePDMAClkOutDivder = AM_HAL_PDM_PDMA_CLKO_DIV15;
            pdmConfig.ui32DecimationRate = 24;
            break;
        case NS_AUDIO_PDM_CLK_1_5MHZ:
            pdmConfig.ePDMAClkOutDivder = AM_HAL_PDM_PDMA_CLKO_DIV7;
            pdmConfig.ui32DecimationRate = 48;
            break;
        }
    } if (cfg->clock == NS_CLKSEL_PLL) {
        pdmConfig.ePDMAClkOutDivder = AM_HAL_PDM_PDMA_CLKO_DIV3;
        pdmConfig.ui32DecimationRate = 48;
    } else {
        pdmConfig.ePDMAClkOutDivder = AM_HAL_PDM_PDMA_CLKO_DIV14;
        pdmConfig.ui32DecimationRate = 24;
    }

    // PDM Channel Config
    if (config->numChannels == 2) {
        pdmConfig.ePCMChannels = AM_HAL_PDM_CHANNEL_STEREO;
    } else {
        pdmConfig.ePCMChannels = AM_HAL_PDM_CHANNEL_LEFT;
    }

    if (cfg->clock == NS_CLKSEL_PLL)
    {
        am_hal_clkmgr_clock_config(AM_HAL_CLKMGR_CLK_ID_SYSPLL, 12288000, NULL);
    }
    else if (cfg->clock == NS_CLKSEL_HFRC)
    {
        #if defined(AM_PART_APOLLO5A)
        // Start the 32MHz crystal rapidly used to adjust HFRC2.
        am_hal_mcuctrl_control(AM_HAL_MCUCTRL_CONTROL_EXTCLK32M_KICK_START, false);
        am_util_delay_us(1500);

        // Enable HFRC2 adjustment.
        am_hal_clkgen_control(AM_HAL_CLKGEN_CONTROL_HF2ADJ_ENABLE, false);
        am_util_delay_us(500);
        #elif defined(AM_PART_APOLLO5B)
        am_hal_clkmgr_clock_config(AM_HAL_CLKMGR_CLK_ID_HFRC2, AM_HAL_CLKMGR_HFRC2_FREQ_ADJ_196P608MHZ, NULL);
        #endif
    }

    // Initialize, power-up, and configure the PDM.
    am_bsp_pdm_pins_enable(cfg->mic);
    am_hal_pdm_initialize(cfg->mic, &pvPDMHandle);
    am_hal_pdm_power_control(pvPDMHandle, AM_HAL_PDM_POWER_ON, false);
    am_hal_pdm_configure(pvPDMHandle, &pdmConfig);

    am_hal_pdm_fifo_threshold_setup(pvPDMHandle, 16);


    am_hal_pdm_fifo_flush(pvPDMHandle);

    // Configure and enable PDM interrupts (set up to trigger on DMA
    // completion).
    am_hal_pdm_interrupt_enable(
        pvPDMHandle,
        (AM_HAL_PDM_INT_DERR | AM_HAL_PDM_INT_DCMP | AM_HAL_PDM_INT_UNDFL | AM_HAL_PDM_INT_OVF));

    // NVIC_SetPriority(g_ePdmInterrupts[cfg->mic],AM_IRQ_PRIORITY_DEFAULT);
    NVIC_SetPriority(g_ePdmInterrupts[cfg->mic], 7);
    NVIC_EnableIRQ(g_ePdmInterrupts[cfg->mic]);

    am_hal_pdm_enable(pvPDMHandle);
    pdm_trigger_dma(config);
    return NS_STATUS_SUCCESS;
}

void pdm_deinit(ns_audio_config_t *config) {
    ns_pdm_cfg_t * cfg = config->pdm_config;
    am_hal_pdm_interrupt_clear(cfg, (AM_HAL_PDM_INT_DERR  |\
                                         AM_HAL_PDM_INT_DCMP  |\
                                         AM_HAL_PDM_INT_UNDFL |\
                                         AM_HAL_PDM_INT_OVF));

    am_hal_pdm_interrupt_disable(cfg, (AM_HAL_PDM_INT_DERR  |\
                                           AM_HAL_PDM_INT_DCMP  |\
                                           AM_HAL_PDM_INT_UNDFL |\
                                           AM_HAL_PDM_INT_OVF));

    NVIC_DisableIRQ(g_ePdmInterrupts[cfg->mic]);


    am_hal_pdm_disable(cfg);
    am_hal_pdm_power_control(cfg, AM_HAL_PDM_POWER_OFF, false);
    am_hal_pdm_deinitialize(cfg);
}

// PDM Interrupt Service Routine (ISR)
void am_pdm_isr_common(uint8_t pdmNumber) {
    uint32_t ui32Status;

#if configUSE_SYSVIEWER
    traceISR_ENTER();
#endif // configUSE_SYSVIEWER

    if (pdmNumber != g_ns_audio_config->pdm_config->mic) {
        return;
    }
    // Read the interrupt status.
    am_hal_pdm_interrupt_status_get(pvPDMHandle, &ui32Status, true);
    am_hal_pdm_interrupt_clear(pvPDMHandle, ui32Status);
        am_hal_pdm_interrupt_service(pvPDMHandle, ui32Status, &(g_ns_audio_config->sTransfer));

    if (ui32Status & AM_HAL_PDM_INT_DCMP) {
    // ns_lp_printf("PDM ISR %d\n", ui32Status);


        uint32_t *ui32PDMDatabuffer = (uint32_t *)am_hal_pdm_dma_get_buffer(pvPDMHandle);

        g_ns_audio_config->callback(g_ns_audio_config, 0);

        // Re-arrange data
        uint8_t *temp1 = (uint8_t *)g_ns_audio_config->audioBuffer;
        for (uint32_t i = 0; i < g_ns_audio_config->numSamples * g_ns_audio_config->numChannels;
             i++) {
            temp1[2 * i] = (ui32PDMDatabuffer[i] & 0xFF00) >> 8U;
            temp1[2 * i + 1] = (ui32PDMDatabuffer[i] & 0xFF0000) >> 16U;
        }

    } else if (ui32Status & (AM_HAL_PDM_INT_UNDFL | AM_HAL_PDM_INT_OVF)) {
        uint32_t count = am_hal_pdm_fifo_count_get(pvPDMHandle);
        #ifdef __GNUC__
        #pragma GCC diagnostic push
        #pragma GCC diagnostic ignored "-Wunused-but-set-variable"
                volatile uint32_t ui32FifoDummy;
                for ( uint8_t i = 0; i < count; i++ )
                {
                    ui32FifoDummy = PDMn(g_ns_audio_config->pdm_config->mic)->FIFOREAD;
                }
        #pragma GCC diagnostic pop
        #endif
        am_hal_pdm_fifo_flush(pvPDMHandle);
        // ns_lp_printf("am_hal_pdm_fifo_flush() %d\n", ui32Status);
    }

#if configUSE_SYSVIEWER
    traceISR_EXIT(); // Should be comment out when it is Apollo 3
#endif               // configUSE_SYSVIEWER
}

void am_pdm0_isr(void) { am_pdm_isr_common(0); }
#ifdef NS_PDM1TO3_PRESENT
void am_pdm1_isr(void) { am_pdm_isr_common(1); }
void am_pdm2_isr(void) { am_pdm_isr_common(2); }
#endif