#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <time.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <string.h>
#include <unistd.h>


#define XAXICDMA_CR_OFFSET       0x00000000  /**< Control register */
#define XAXICDMA_SR_OFFSET       0x00000004  /**< Status register */

#define XAXICDMA_SRCADDR_OFFSET 0x00000018  /**< Source address register */
#define XAXICDMA_DSTADDR_OFFSET 0x00000020  /**< Destination address register */
#define XAXICDMA_BTT_OFFSET     0x00000028  /**< Bytes to transfer */

                                        
#define XAXICDMA_XR_IRQ_IOC_MASK 0x00001000 /**< Completion interrupt */
#define XAXICDMA_XR_IRQ_DELAY_MASK  0x00002000 /**< Delay interrupt */
#define XAXICDMA_XR_IRQ_ERROR_MASK  0x00004000 /**< Error interrupt */
#define XAXICDMA_XR_IRQ_ALL_MASK 0x00007000 /**< All interrupts */
#define XAXICDMA_XR_IRQ_SIMPLE_ALL_MASK   0x00005000 /**< All interrupts for
                                                        simple only mode */

                                          
#define BUFFER_BYTESIZE     1024 // Length of the buffers for DMA transfer from DDR to BRAM
#define MAP_SIZE 4096

#define DDR_MAP_SIZE 0x10000
#define DDR_MAP_MASK (DDR_MAP_SIZE - 1)

typedef unsigned int u64;

unsigned int dma_set(unsigned int* dma_virtual_address, int offset, unsigned int value) {
    dma_virtual_address[offset>>2] = value;
}

unsigned int dma_get(unsigned int* dma_virtual_address, int offset) {
    return dma_virtual_address[offset>>2];
}

int main()
{

   int fd, count = 0;
   u64 *vadd_bram, *vadd_psddr, *vadd_cdma;
   off_t BRAM_pbase = 0xA0000000;
   off_t PSDDR_pbase = 0x4000000;
   off_t CDMA_pbase = 0x400000000;
   
   fd = open("/dev/mem", O_RDWR | O_SYNC);
   if (fd == -1)
   {
      printf("Can't open /dev/mem.\n");
      exit(0);
   }
   printf("/dev/mem opened.\n");

   vadd_bram = (u64 *)mmap(0, MAP_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd, BRAM_pbase);
   if(vadd_bram == (u64 *) -1)
   {
      printf("Can't map the BRAM memory to user space.\n");
      exit(0);
   }
   printf("BRAM Memory mapped at address %p.\n", vadd_bram);

   vadd_psddr = (u64 *)mmap(0, DDR_MAP_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd, PSDDR_pbase);
   if(vadd_psddr == (u64 *) -1) 
   {
      printf("Can't map the PSDDR memory to user space.\n");
        exit(0);
    }
   printf("PSDDR Memory mapped at address %p.\n", vadd_psddr);

   vadd_cdma = (u64 *)mmap(0, MAP_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd, CDMA_pbase);
   if(vadd_cdma == (u64 *) -1)  
   {
      printf("Can't map the CDMA memory to user space.\n");
        exit(0);
    }
    printf("CDMA Memory mapped at address %p.\n", vadd_cdma);
   
      for(int i = 0; i < 100; i++)
      {
         vadd_psddr[i] = i;
         printf("Input : value in PSDDR %d : value in BRAM %d\r\n", vadd_psddr[i], vadd_bram[i]);
      }

    unsigned int reg = dma_get(vadd_cdma, XAXICDMA_CR_OFFSET);
    unsigned int status = dma_get(vadd_cdma, XAXICDMA_SR_OFFSET);
    printf("control reg:0x%08x\n", reg);
    printf("status reg:0x%08x\n", status);

     
    printf("all interrupts masked...\n");
    dma_set(vadd_cdma, XAXICDMA_CR_OFFSET, XAXICDMA_XR_IRQ_SIMPLE_ALL_MASK);
    reg = dma_get(vadd_cdma, XAXICDMA_CR_OFFSET);
    status = dma_get(vadd_cdma, XAXICDMA_SR_OFFSET);
    printf("control reg:0x%08x\n", reg);
    printf("status reg:0x%08x\n", status); 
      

    printf("Writing source address\n");
    dma_set(vadd_cdma, XAXICDMA_SRCADDR_OFFSET, PSDDR_pbase);
 
    reg = dma_get(vadd_cdma, XAXICDMA_SRCADDR_OFFSET);
    status = dma_get(vadd_cdma, XAXICDMA_SR_OFFSET);
    printf("Source addr reg:0x%08x\n", reg);
    printf("status reg:0x%08x\n", status);

    printf("Writing destination address\n");
    dma_set(vadd_cdma, XAXICDMA_DSTADDR_OFFSET, BRAM_pbase);

    reg = dma_get(vadd_cdma, XAXICDMA_DSTADDR_OFFSET);
    status = dma_get(vadd_cdma, XAXICDMA_SR_OFFSET);
    printf("Dest addr reg:0x%08x\n", reg);
    printf("status reg:0x%08x\n", status);

    printf("Writing transfer length...\n");
    dma_set(vadd_cdma, XAXICDMA_BTT_OFFSET, 0x190); // write length register
   
   while(1)
   {
      status = dma_get(vadd_cdma, XAXICDMA_SR_OFFSET);
      if(status & (1 << 12))
      {
         printf("DMA transfer is completed \n");
         break;
      }
       
   }
    reg = dma_get(vadd_cdma, XAXICDMA_BTT_OFFSET);
    status = dma_get(vadd_cdma, XAXICDMA_SR_OFFSET);
    printf("length reg:0x%08x\n", reg);
    printf("status reg:0x%08x\n", status);
   
    for(int i = 0; i < 100; i++)
    {
         printf("Output : value in PSDDR %d : value in BRAM %d \r\n", vadd_psddr[i], vadd_bram[i]);
         if(vadd_psddr[i] != vadd_bram[i])
         {
              count++;
         }
    }

   if(!count)
   {
      printf("Transmitted Data successfully\n");
   }
   else
   {
      printf("Transmitted data Mismatched : %d\n", count);
   }
 
}