HLS Core Stalling During DMA Operation on Eclypse Z7

[Julii]

Hello Digilent Community,

I am currently developing a project on the Eclypse Z7 and am integrating several HLS components. I would appreciate any insights or suggestions you could provide regarding my implementation.

Project Overview

I am using Vitis HLS 2023.1 for synthesizing the FPGA components. The project includes data streaming operations where input data is processed and sent to different output channels, as described in the HLS code below.

HLS Code

Here's the HLS code for handling data streams:

#include "main.h"

void read_in(
    data_stream_type& indatastream,
	internal_stream_data_type& internal_stream
) {

    data_stream_t data_in_struct;
    internal_stream_data_t internal_struct;

    static int call_count = 0;  // Static variable to track the number of times the function is called

    PROCESSING_LOOP: for (int ii = 0; ii < N_INPUT; ii+=2) {
        // Read data from the input stream
        data_in_struct = indatastream.read();

		ap_uint<32> data = data_in_struct.data;


		internal_struct.data = data;
        internal_struct.last = (ii == N_INPUT-2 && call_count == N_STEPS-1) ? 1 : 0;

		internal_stream.write(internal_struct);
   }
   call_count++;  // Increment call count after processing each call
   if (call_count >= N_STEPS) call_count = 0;  // Reset after processing all steps

}

void stream_to_ps(
		internal_stream_data_type& internal_stream,
		data_stream_type& to_ps) {

    data_stream_t to_ps_struct;
    internal_stream_data_t internal_struct;

    TO_PS_LOOP: for (int ii = 0; ii < N_INPUT; ii+=2) {
    	internal_struct = internal_stream.read();

    	to_ps_struct.data = internal_struct.data;
    	to_ps_struct.last = internal_struct.last;

    	to_ps.write(to_ps_struct);

    }

}


void stream_out(
		data_stream_type& outdatastream) {

    data_stream_t data_out_struct;
    static int call_count = 1;  // Static variable to track the number of times the function is called

	ap_uint<16> result_16_1 = (ap_uint<16>) 30000/call_count;
	ap_uint<16> result_16_2 = (ap_uint<16>) 123;

	// Correctly pack result_16 and out_val into a single ap_uint<32> variable
	ap_uint<32> combined = (static_cast<ap_uint<32>>(result_16_1) << 16) | static_cast<ap_uint<16>>(result_16_2);

	data_out_struct.data = combined;
	outdatastream.write(data_out_struct);
    call_count++;
    if (call_count >= N_STEPS+1) call_count = 1;  // Reset after processing all steps


}

void episode_processing(
		data_stream_type& indatastream,
		data_stream_type& outdatastream,
		data_stream_type& to_ps) {

	READING_LOOP: for (int i = 0; i < N_STEPS; i++) {
		#pragma HLS DATAFLOW
		internal_stream_data_type internal_stream;
		#pragma HLS STREAM variable=internal_stream depth=2004

		read_in(indatastream, internal_stream);
		stream_to_ps(internal_stream, to_ps);
		stream_out(outdatastream);
	}
	ap_uint<16> result_16_1 = (ap_uint<16>) 0;
	ap_uint<16> result_16_2 = (ap_uint<16>) 0;

	// Correctly pack result_16 and out_val into a single ap_uint<32> variable
	ap_uint<32> combined = (static_cast<ap_uint<32>>(result_16_1) << 16) | static_cast<ap_uint<16>>(result_16_2);
    data_stream_t data_out_struct;

	data_out_struct.data = combined;
	outdatastream.write(data_out_struct);


}


ap_uint<1> level_1_HLS_stream_simplified(
		data_stream_type& indatastream,
		data_stream_type& outdatastream,
		data_stream_type& to_ps,
		out_data_t th,
		ap_uint<1> sinitdoneadc,
		ap_uint<1> sinitdonedac,
		ap_uint<1> sinitdonerelay) {


	#pragma HLS INTERFACE axis port=indatastream
	#pragma HLS INTERFACE axis port=outdatastream
	#pragma HLS INTERFACE axis port=to_ps

	#pragma HLS INTERFACE s_axilite port=th
	#pragma HLS INTERFACE s_axilite port=return

	#pragma HLS INTERFACE ap_none port=sinitdoneadc
	#pragma HLS INTERFACE ap_none port=sinitdonedac
	#pragma HLS INTERFACE ap_none port=sinitdonerelay

	bool done = false;
    data_stream_t data_in_struct;

    if (sinitdoneadc && sinitdonedac && sinitdonerelay) {
    	while(!done) {
    		// Read data from the input stream
    		data_in_struct = indatastream.read();

			// Unpack the data
			ap_uint<32> data = data_in_struct.data;
			ap_int<16> sample1 = data.range(31, 16); // First sample
			ap_int<16> sample2 = data.range(15, 0);   // Second sample

    		if ((sample1 >= th) || (sample2 >= th)) {
    			episode_processing(indatastream, outdatastream, to_ps);
    			done = true;
    		}
    	}
	}

    return (ap_uint<1>) 1;
}

and the following is the main.h: 

#ifndef MLP_TOP_H
#define MLP_TOP_H

#include <hls_stream.h>
#include <ap_int.h>
#include <ap_axi_sdata.h>
#include "hls_half.h"

typedef ap_int<16> out_data_t;
typedef ap_int<8> in_data_t;

typedef ap_axiu<32, 0, 0, 0> data_stream_t;
typedef hls::stream<data_stream_t> data_stream_type;

typedef struct {
	ap_uint<32> data;
    ap_uint<1> last;
} internal_stream_data_t;
typedef hls::stream<internal_stream_data_t> internal_stream_data_type;


#define N_INPUT 2000

#define N_STEPS 2


ap_uint<1> level_1_HLS_stream_simplified(
		data_stream_type& indatastream, data_stream_type& outdatastream,
		data_stream_type& to_ps, out_data_t th,
		ap_uint<1> sinitdoneadc, ap_uint<1> sinitdonedac, ap_uint<1> sinitdonerelay);


#endif // MLP_TOP_H

This is my Vivado block diagram: 

And this is the IDE code: 

#include <stdio.h>
#include "xil_printf.h"
#include "xaxidma.h"
#include "xparameters.h"
#include "xlevel_1_hls_stream_simplified.h"

XAxiDma AxiDma;
const int AXI_DMA_ID = XPAR_AXI_DMA_0_DEVICE_ID;
const int DEV_ID = XPAR_LEVEL_1_HLS_STREAM_S_0_DEVICE_ID;

#define N_STEPS 2
#define MAX_VAL 32767 // Which corresponds to 5V
#define TH 1000
#define N_INPUT 2000
#define N_RUNS 20

typedef u32 out_data_t;
u32 recv_buffer[N_STEPS*N_INPUT/2];

int InitializeDMA() {
    XAxiDma_Config *CfgPtr;
    int Status;

    CfgPtr = XAxiDma_LookupConfig(AXI_DMA_ID);
    if (!CfgPtr) {
        xil_printf("No config found for DMA %d\r\n", AXI_DMA_ID);
        return XST_FAILURE;
    }

    Status = XAxiDma_CfgInitialize(&AxiDma, CfgPtr);
    if (Status != XST_SUCCESS) {
        xil_printf("DMA Initialization failed %d\r\n", Status);
        return XST_FAILURE;
    }

    if (XAxiDma_HasSg(&AxiDma)) {
        xil_printf("Device configured as SG mode \r\n");
        return XST_FAILURE;
    }

    XAxiDma_Reset(&AxiDma);
    XAxiDma_IntrDisable(&AxiDma, XAXIDMA_IRQ_ALL_MASK, XAXIDMA_DEVICE_TO_DMA);
    XAxiDma_IntrDisable(&AxiDma, XAXIDMA_IRQ_ALL_MASK, XAXIDMA_DMA_TO_DEVICE);

    return XST_SUCCESS;
}

int main() {
    XLevel_1_hls_stream_simplified Instance;
    XLevel_1_hls_stream_simplified_Config *ConfigPtr;
    int status;
    u32 th;
    u32 *DataBufferPtr = (u32 *)recv_buffer;

    xil_printf("Let's start!\n\r");

    ConfigPtr = XLevel_1_hls_stream_simplified_LookupConfig(DEV_ID);
    status = XLevel_1_hls_stream_simplified_CfgInitialize(&Instance, ConfigPtr);
    if (status == XST_SUCCESS) {
        xil_printf("Successfully configured HLS core.\n\r");
    }

    status = InitializeDMA();
    if (status != XST_SUCCESS) {
        xil_printf("Data DMA In Initialization Failed\r\n");
        return XST_FAILURE;
    }

    XLevel_1_hls_stream_simplified_InterruptGlobalDisable(&Instance);
    XLevel_1_hls_stream_simplified_Set_th(&Instance, TH);
    th = XLevel_1_hls_stream_simplified_Get_th(&Instance);
    xil_printf("TH set to: %lu\n\r", th);

    u32 bytes_to_read = N_STEPS * N_INPUT * sizeof(u32) / 2;
    xil_printf("Bytes to read: %d\n\r", bytes_to_read);

    Xil_DCacheFlushRange((UINTPTR)DataBufferPtr, bytes_to_read + 16);
    status = XAxiDma_SimpleTransfer(&AxiDma, (UINTPTR)DataBufferPtr, bytes_to_read, XAXIDMA_DEVICE_TO_DMA);

    if (status != XST_SUCCESS) {
        xil_printf("Failed to start DMA transfer\r\n");
        xil_printf("Status %d", status);
        return XST_FAILURE;
    }

    XLevel_1_hls_stream_simplified_Start(&Instance);
    xil_printf("Ready to go\n\r");

    while (XAxiDma_Busy(&AxiDma, XAXIDMA_DEVICE_TO_DMA));
    xil_printf("DMA is done. \n\r");

    while (!XLevel_1_hls_stream_simplified_IsDone(&Instance));
    xil_printf("HLS is done. \n\r");

    Xil_DCacheInvalidateRange((UINTPTR)DataBufferPtr, bytes_to_read + 16);
    xil_printf("Received data: ");
    for (int i = 0; i < N_STEPS * N_INPUT / 2; i++) {
        if (i > 0) xil_printf(", ");
        if (i % 1000 == 0) xil_printf("%d", DataBufferPtr[i]);
    }
    xil_printf("\n\r");

    return 0;
}

The HLS code functions correctly as confirmed by C/RTL simulations. The DMA is configured with a Width of Buffer Length Register set to 26 bits, and the FIFO depth is set at 8192.

When executing the XLevel_1_hls_stream_simplified_Start(&Instance); command, the HLS core initiates correctly. This is evident from the DAC output, which reaches approximately 5V for 10 microseconds, then drops to 2.5V for another 10 microseconds before falling to zero. However, the execution gets consistently stuck at while (XAxiDma_Busy(&AxiDma, XAXIDMA_DEVICE_TO_DMA));, indicating that the DMA remains busy.

I've verified with an Integrated Logic Analyzer (ILA) that the tlast signal transitions to 1 as expected. Despite this, the issue persists, leaving me searching for further troubleshooting steps or insights.

This is the waveform I get from the ILA connected to the to_ps AXIS interface of the HLS core: 
start:

and end: 

 

Thank you in advance for any assistance you can provide!

 

 

Edited April 29 by Julii

[artvvb]

Hi @Julii

 

 

If I understand correctly: The HLS IP reads data from the ZmodScopeController until either of the two channels exceeds a threshold. Once that occurs, it sends a pulse to the ZmodAWGController. It also forwards the next 2000 samples from the input to the PS via DMA. The data to be forwarded is buffered inside the HLS IP in a 2000-or-so-word-deep FIFO, which is used to ensure that backpressure from the DMA doesn't cause samples to drop. Is that accurate? I don't quite follow why functions called in episode_processing are called N_STEPS times.

Couple ideas for debugging:

1. Inspect the DMA status register while it's sitting in the loop - maybe there's an error bit set. I'd use an expression in the debugger dereferencing a pointer to the register address for this. The Memory view could also work but has some bugs with the DMA.

2. Confirm that the HLS IP doesn't start until after the DMA is ready to receive - the ready signal is not enough to rely on, as it's asserted when the DMA comes out of reset.

3. Get software access to all of the AWG and scope controller status pins - reading sDataOverflow could give some more info about stream pressure in the system for example.

I would also consider having the HLS IP read from the input stream from the scope continuously - waiting until the AWG controller is also ready means that if the AWG comes up later, the scope controller's internal fifo will overflow.

Thanks,

ARthur

 

 

[Julii]

Hi @artvvb

 

Thanks for your reply. 

12 hours ago, artvvb said:

[...]If I understand correctly: The HLS IP reads data from the ZmodScopeController until either of the two channels exceeds a threshold. Once that occurs, it sends a pulse to the ZmodAWGController. It also forwards the next 2000 samples from the input to the PS via DMA. The data to be forwarded is buffered inside the HLS IP in a 2000-or-so-word-deep FIFO, which is used to ensure that backpressure from the DMA doesn't cause samples to drop. Is that accurate? I don't quite follow why functions called in episode_processing are called N_STEPS times.

Indeed, you've got the core concept correct. The HLS IP continuously reads data from the ZmodScopeController until a signal on one of the two channels surpasses a predefined threshold. Once this condition is met, it triggers the episode_processing function to execute N_STEPS times. In each iteration, the HLS IP sends a distinct pulse to the ZmodAWGController and forwards the next 2000 samples from the input to the Processing System (PS) via DMA. The use of the internal stream was just a desperate attempt (😁) to make it work, same for the external FIFO. Do they make sense? 

The repetition of episode_processing N_STEPS times is only related to this simplified version I'm using for debugging. In reality, the IP conducts specific data processing on the inputs received from the ADC. It then determines the appropriate outputs to send to the DAC based on this analysis. Each of these operations must occur sequentially, directly after the preceding one, upon exceeding the threshold, hence the multiple iterations.
 

12 hours ago, artvvb said:

[...]
Couple ideas for debugging:

1. Inspect the DMA status register while it's sitting in the loop - maybe there's an error bit set. I'd use an expression in the debugger dereferencing a pointer to the register address for this. The Memory view could also work but has some bugs with the DMA.

2. Confirm that the HLS IP doesn't start until after the DMA is ready to receive - the ready signal is not enough to rely on, as it's asserted when the DMA comes out of reset.

3. Get software access to all of the AWG and scope controller status pins - reading sDataOverflow could give some more info about stream pressure in the system for example.

I would also consider having the HLS IP read from the input stream from the scope continuously - waiting until the AWG controller is also ready means that if the AWG comes up later, the scope controller's internal fifo will overflow.

[...]

 

 

Not sure I got everything here, I've implemented this function to try to check the DMA register, is this what you meant? 

/ -----------------------------------------------
// DMA Base Address
#define DMA_BASE_ADDR XPAR_AXI_DMA_0_BASEADDR

// DMA Register Offsets
#define S2MM_DMACR_OFFSET 0x30  // Control Register
#define S2MM_DMASR_OFFSET 0x34  // Status Register

// DMA Status Register Bit Masks
#define HALTED_MASK         0b00000000000000000000000000000001
#define IDLE_MASK           0b00000000000000000000000000000010
#define DMA_INT_ERROR_MASK  0b00000000000000000000000000010000
#define DMA_SLV_ERROR_MASK  0b00000000000000000000000000100000
#define DMA_DEC_ERROR_MASK  0b00000000000000000000000001000000
#define SG_INT_ERROR_MASK   0b00000000000000000000000100000000
#define SG_SLV_ERROR_MASK   0b00000000000000000000001000000000
#define SG_DEC_ERROR_MASK   0b00000000000000000000010000000000
#define IOC_IRQ_MASK        0b00000000000000000001000000000000
#define DLY_IRQ_MASK        0b00000000000000000010000000000000
#define ERR_IRQ_MASK        0b00000000000000000100000000000000

// Define macros for accessing registers
#define DMA_S2MM_DMACR (*((volatile unsigned int*)(DMA_BASE_ADDR + S2MM_DMACR_OFFSET)))
#define DMA_S2MM_DMASR (*((volatile unsigned int*)(DMA_BASE_ADDR + S2MM_DMASR_OFFSET)))

void check_dma_status() {
    volatile unsigned int status = DMA_S2MM_DMASR;

    xil_printf("Checking DMA Status...\r\n");
    xil_printf("DMA Status Register: 0x%X\r\n", status);

    // Check if the DMA is halted
    if (status & HALTED_MASK) {
        xil_printf("DMA is halted.\r\n");
    } else {
        xil_printf("DMA is running.\r\n");
    }

    // Check if the DMA is idle
    if (status & IDLE_MASK) {
        xil_printf("DMA is idle.\r\n");
    } else {
        xil_printf("DMA is active.\r\n");
    }

    // Check for different types of errors
    if (status & DMA_INT_ERROR_MASK) {
        xil_printf("DMA Internal Error detected.\r\n");
    }
    if (status & DMA_SLV_ERROR_MASK) {
        xil_printf("DMA Slave Error detected.\r\n");
    }
    if (status & DMA_DEC_ERROR_MASK) {
        xil_printf("DMA Decode Error detected.\r\n");
    }
    if (status & SG_INT_ERROR_MASK) {
        xil_printf("SG Internal Error detected.\r\n");
    }
    if (status & SG_SLV_ERROR_MASK) {
        xil_printf("SG Slave Error detected.\r\n");
    }
    if (status & SG_DEC_ERROR_MASK) {
        xil_printf("SG Decode Error detected.\r\n");
    }

    // Check for interrupts
    if (status & IOC_IRQ_MASK) {
        xil_printf("Interrupt on Complete detected.\r\n");
    }
    if (status & DLY_IRQ_MASK) {
        xil_printf("Interrupt on Delay detected.\r\n");
    }
    if (status & ERR_IRQ_MASK) {
        xil_printf("Error Interrupt detected.\r\n");
    }
}

And also, I introduced a GPIO IP to check the control signals of the ADC and DAC. This it the full code: 
 

#include <stdio.h>
#include "xil_printf.h"
#include "xaxidma.h"
#include "xparameters.h"
#include "xlevel_1_hls_stream_simplified.h"
#include "xgpio.h"

// Define GPIO Device instance
XGpio Gpio;
u32 Data;

#define GPIO_DEVICE_ID XPAR_GPIO_0_DEVICE_ID


XAxiDma AxiDma;
const int AXI_DMA_ID = XPAR_AXI_DMA_0_DEVICE_ID;
const int DEV_ID = XPAR_LEVEL_1_HLS_STREAM_S_0_DEVICE_ID;

#define N_STEPS 1
#define MAX_VAL 32767 // Which corresponds to 5V
#define TH 500
#define N_INPUT 8
#define N_RUNS 20

#define RX_BUFFER XPAR_PS7_DDR_0_S_AXI_BASEADDR

typedef u32 out_data_t;
u32 recv_buffer[ N_STEPS*N_INPUT/2 ] __attribute__((aligned(4)));

// -----------------------------------------------
// DMA Base Address
#define DMA_BASE_ADDR XPAR_AXI_DMA_0_BASEADDR

// DMA Register Offsets
#define S2MM_DMACR_OFFSET 0x30  // Control Register
#define S2MM_DMASR_OFFSET 0x34  // Status Register

// DMA Status Register Bit Masks
#define HALTED_MASK         0b00000000000000000000000000000001
#define IDLE_MASK           0b00000000000000000000000000000010
#define DMA_INT_ERROR_MASK  0b00000000000000000000000000010000
#define DMA_SLV_ERROR_MASK  0b00000000000000000000000000100000
#define DMA_DEC_ERROR_MASK  0b00000000000000000000000001000000
#define SG_INT_ERROR_MASK   0b00000000000000000000000100000000
#define SG_SLV_ERROR_MASK   0b00000000000000000000001000000000
#define SG_DEC_ERROR_MASK   0b00000000000000000000010000000000
#define IOC_IRQ_MASK        0b00000000000000000001000000000000
#define DLY_IRQ_MASK        0b00000000000000000010000000000000
#define ERR_IRQ_MASK        0b00000000000000000100000000000000

// Define macros for accessing registers
#define DMA_S2MM_DMACR (*((volatile unsigned int*)(DMA_BASE_ADDR + S2MM_DMACR_OFFSET)))
#define DMA_S2MM_DMASR (*((volatile unsigned int*)(DMA_BASE_ADDR + S2MM_DMASR_OFFSET)))

void check_dma_status() {
    volatile unsigned int status = DMA_S2MM_DMASR;

    xil_printf("Checking DMA Status...\r\n");
    xil_printf("DMA Status Register: 0x%X\r\n", status);

    // Check if the DMA is halted
    if (status & HALTED_MASK) {
        xil_printf("DMA is halted.\r\n");
    } else {
        xil_printf("DMA is running.\r\n");
    }

    // Check if the DMA is idle
    if (status & IDLE_MASK) {
        xil_printf("DMA is idle.\r\n");
    } else {
        xil_printf("DMA is active.\r\n");
    }

    // Check for different types of errors
    if (status & DMA_INT_ERROR_MASK) {
        xil_printf("DMA Internal Error detected.\r\n");
    }
    if (status & DMA_SLV_ERROR_MASK) {
        xil_printf("DMA Slave Error detected.\r\n");
    }
    if (status & DMA_DEC_ERROR_MASK) {
        xil_printf("DMA Decode Error detected.\r\n");
    }
    if (status & SG_INT_ERROR_MASK) {
        xil_printf("SG Internal Error detected.\r\n");
    }
    if (status & SG_SLV_ERROR_MASK) {
        xil_printf("SG Slave Error detected.\r\n");
    }
    if (status & SG_DEC_ERROR_MASK) {
        xil_printf("SG Decode Error detected.\r\n");
    }

    // Check for interrupts
    if (status & IOC_IRQ_MASK) {
        xil_printf("Interrupt on Complete detected.\r\n");
    }
    if (status & DLY_IRQ_MASK) {
        xil_printf("Interrupt on Delay detected.\r\n");
    }
    if (status & ERR_IRQ_MASK) {
        xil_printf("Error Interrupt detected.\r\n");
    }
}

int InitializeDMA() {
    XAxiDma_Config *CfgPtr;
    int Status;

    CfgPtr = XAxiDma_LookupConfig(AXI_DMA_ID);
    if (!CfgPtr) {
        xil_printf("No config found for DMA %d\r\n", AXI_DMA_ID);
        return XST_FAILURE;
    }

    Status = XAxiDma_CfgInitialize(&AxiDma, CfgPtr);
    if (Status != XST_SUCCESS) {
        xil_printf("DMA Initialization failed %d\r\n", Status);
        return XST_FAILURE;
    }

    if (XAxiDma_HasSg(&AxiDma)) {
        xil_printf("Device configured as SG mode \r\n");
        return XST_FAILURE;
    }

    XAxiDma_Reset(&AxiDma);
    XAxiDma_IntrDisable(&AxiDma, XAXIDMA_IRQ_ALL_MASK, XAXIDMA_DEVICE_TO_DMA);
    XAxiDma_IntrDisable(&AxiDma, XAXIDMA_IRQ_ALL_MASK, XAXIDMA_DMA_TO_DEVICE);

    return XST_SUCCESS;
}

int main() {
    XLevel_1_hls_stream_simplified Instance;
    XLevel_1_hls_stream_simplified_Config *ConfigPtr;
    int status;
    u32 th;
    u32 *DataBufferPtr = (u32 *)recv_buffer;

    xil_printf("Let's start!\n\r");

    // Initialize GPIO device
	int Status = XGpio_Initialize(&Gpio, GPIO_DEVICE_ID);
	if (Status != XST_SUCCESS) {
		return XST_FAILURE;
	}
	// Set all pins as input (for 7 signals use 0b1111111 which is 0x7F in hexadecimal)
	XGpio_SetDataDirection(&Gpio, 1, 0x7F);

	// Read the state of the input pins
	Data = XGpio_DiscreteRead(&Gpio, 1);

	// Print the states of each signal
    xil_printf("Control signals Before initializing the HLS ip.\n\r");
	printf("Control Signals State:\n");
	printf("sInitDoneDAC: %lu\n", (Data >> 0) & 0x1);
	printf("sConfigError: %lu\n", (Data >> 1) & 0x1);
	printf("sRstBusy: %lu\n", (Data >> 2) & 0x1);
	printf("sInitDoneADC: %lu\n", (Data >> 3) & 0x1);
	printf("sConfigError: %lu\n", (Data >> 4) & 0x1);
	printf("sInitDoneRelay: %lu\n", (Data >> 5) & 0x1);
	printf("sDataOverflow: %lu\n", (Data >> 6) & 0x1);
	check_dma_status();
    xil_printf("-----------------------------------.\n\r");


    ConfigPtr = XLevel_1_hls_stream_simplified_LookupConfig(DEV_ID);
    status = XLevel_1_hls_stream_simplified_CfgInitialize(&Instance, ConfigPtr);
    if (status == XST_SUCCESS) {
        xil_printf("Successfully configured HLS core.\n\r");
    }

    status = InitializeDMA();
    if (status != XST_SUCCESS) {
        xil_printf("Data DMA In Initialization Failed\r\n");
        return XST_FAILURE;
    }

    XLevel_1_hls_stream_simplified_InterruptGlobalDisable(&Instance);
    XLevel_1_hls_stream_simplified_Set_th(&Instance, TH);
    th = XLevel_1_hls_stream_simplified_Get_th(&Instance);
    xil_printf("TH set to: %lu\n\r", th);

	// Read the state of the input pins
	Data = XGpio_DiscreteRead(&Gpio, 1);

	// Print the states of each signal
    xil_printf("Control signals Before Starting the HLS ip.\n\r");
	printf("Control Signals State:\n");
	printf("sInitDoneDAC: %lu\n", (Data >> 0) & 0x1);
	printf("sConfigError: %lu\n", (Data >> 1) & 0x1);
	printf("sRstBusy: %lu\n", (Data >> 2) & 0x1);
	printf("sInitDoneADC: %lu\n", (Data >> 3) & 0x1);
	printf("sConfigError: %lu\n", (Data >> 4) & 0x1);
	printf("sInitDoneRelay: %lu\n", (Data >> 5) & 0x1);
	printf("sDataOverflow: %lu\n", (Data >> 6) & 0x1);
	check_dma_status();
    xil_printf("-----------------------------------.\n\r");


    u32 bytes_to_read = N_STEPS * N_INPUT * sizeof(u32) / 2;
    xil_printf("Bytes to read: %d\n\r", bytes_to_read);


    XLevel_1_hls_stream_simplified_Start(&Instance);
    xil_printf("Ready to go\n\r");

	// Read the state of the input pins
	Data = XGpio_DiscreteRead(&Gpio, 1);

	// Print the states of each signal
    xil_printf("Control signals After Starting the HLS ip.\n\r");
	printf("Control Signals State:\n");
	printf("sInitDoneDAC: %lu\n", (Data >> 0) & 0x1);
	printf("sConfigError: %lu\n", (Data >> 1) & 0x1);
	printf("sRstBusy: %lu\n", (Data >> 2) & 0x1);
	printf("sInitDoneADC: %lu\n", (Data >> 3) & 0x1);
	printf("sConfigError: %lu\n", (Data >> 4) & 0x1);
	printf("sInitDoneRelay: %lu\n", (Data >> 5) & 0x1);
	printf("sDataOverflow: %lu\n", (Data >> 6) & 0x1);
	check_dma_status();
    xil_printf("-----------------------------------.\n\r");

    Xil_DCacheFlushRange((UINTPTR)DataBufferPtr, bytes_to_read);
    status = XAxiDma_SimpleTransfer(&AxiDma, (UINTPTR)DataBufferPtr, bytes_to_read, XAXIDMA_DEVICE_TO_DMA);

    if (status != XST_SUCCESS) {
        xil_printf("Failed to start DMA transfer\r\n");
        xil_printf("Status %d", status);
        return XST_FAILURE;
    }

    while (!XLevel_1_hls_stream_simplified_IsDone(&Instance));
    xil_printf("HLS is done. \n\r");

	// Read the state of the input pins
	Data = XGpio_DiscreteRead(&Gpio, 1);

	// Print the states of each signal
    xil_printf("Control signals After the HLS ip is done.\n\r");
	printf("Control Signals State:\n");
	printf("sInitDoneDAC: %lu\n", (Data >> 0) & 0x1);
	printf("sConfigError: %lu\n", (Data >> 1) & 0x1);
	printf("sRstBusy: %lu\n", (Data >> 2) & 0x1);
	printf("sInitDoneADC: %lu\n", (Data >> 3) & 0x1);
	printf("sConfigError: %lu\n", (Data >> 4) & 0x1);
	printf("sInitDoneRelay: %lu\n", (Data >> 5) & 0x1);
	printf("sDataOverflow: %lu\n", (Data >> 6) & 0x1);
	check_dma_status();
    xil_printf("-----------------------------------.\n\r");

    while (XAxiDma_Busy(&AxiDma, XAXIDMA_DEVICE_TO_DMA));
    xil_printf("DMA is done. \n\r");

    Xil_DCacheInvalidateRange((UINTPTR)DataBufferPtr, bytes_to_read);
    xil_printf("Received data: ");
    for (int i = 0; i < N_STEPS * N_INPUT / 2; i++) {
        if (i > 0) xil_printf(", ");
        if (i % 1000 == 0) xil_printf("%d", DataBufferPtr[i]);
    }
    xil_printf("\n\r");

    return 0;
}

And this is what I see as output: 

Let's start!
Control signals Before initializing the HLS ip.
Control Signals State:
sInitDoneDAC: 1
sConfigError: 0
sRstBusy: 0
sInitDoneADC: 1
sConfigError: 0
sInitDoneRelay: 1
sDataOverflow: 1
Checking DMA Status...
DMA Status Register: 0x1
DMA is halted.
DMA is active.
-----------------------------------.
Successfully configured HLS core.
TH set to: 500
Control signals Before Starting the HLS ip.
Control Signals State:
sInitDoneDAC: 1
sConfigError: 0
sRstBusy: 0
sInitDoneADC: 1
sConfigError: 0
sInitDoneRelay: 1
sDataOverflow: 1
Checking DMA Status...
DMA Status Register: 0x1
DMA is halted.
DMA is active.
-----------------------------------.
Bytes to read: 16
Ready to go
Control signals After Starting the HLS ip.
Control Signals State:
sInitDoneDAC: 1
sConfigError: 0
sRstBusy: 0
sInitDoneADC: 1
sConfigError: 0
sInitDoneRelay: 1
sDataOverflow: 1
Checking DMA Status...
DMA Status Register: 0x1
DMA is halted.
DMA is active.
-----------------------------------.
HLS is done. 
Control signals After the HLS ip is done.
Control Signals State:
sInitDoneDAC: 1
sConfigError: 0
sRstBusy: 0
sInitDoneADC: 1
sConfigError: 0
sInitDoneRelay: 1
sDataOverflow: 1
Checking DMA Status...
DMA Status Register: 0x0
DMA is running.
DMA is active.
-----------------------------------.

The ADC is indeed overflowing and the DMA status register is initially halted and keeps being 'running' after I started the HLS IP. But I'm not sure this is the expected behavior or not. 

Any insights or further recommendations you could provide would be greatly appreciated!