///////////////////////////////////////
/// 640x480 version!
/// test VGA with hardware video input copy to VGA
// compile with
// gcc pio_test_2.c -o pio2 
///////////////////////////////////////
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/ipc.h> 
#include <sys/shm.h> 
#include <sys/mman.h>
#include <sys/time.h> 
#include <math.h> 

// main bus; PIO
#define FPGA_AXI_BASE 	0xC0000000
#define FPGA_AXI_SPAN   0x00001000
// main axi bus base
void *h2p_virtual_base;
volatile unsigned int * axi_pio_ptr = NULL ;
volatile unsigned int * axi_pio_read_ptr = NULL ;

// lw bus; PIO
#define FPGA_LW_BASE 	0xff200000
#define FPGA_LW_SPAN	0x00001000
// the light weight bus base
void *h2p_lw_virtual_base;
// HPS_to_FPGA FIFO status address = 0
volatile unsigned int * lw_pio_ptr = NULL ;
volatile unsigned int * lw_pio_read_ptr = NULL ;

// read offset is 0x10 for both busses
// remember that eaxh axi master bus needs unique address
#define FPGA_PIO_READ	0x10
#define FPGA_PIO_WRITE	0x00


// /dev/mem file id
int fd;	

// timing vars
// timer variables
struct timeval t1, t2;
double elapsedTime;
	
int main(void)
{

	// Declare volatile pointers to I/O registers (volatile 	
	// means that IO load and store instructions will be used 	
	// to access these pointer locations,  
  
	// === get FPGA addresses ==================
    // Open /dev/mem
	if( ( fd = open( "/dev/mem", ( O_RDWR | O_SYNC ) ) ) == -1 ) 	{
		printf( "ERROR: could not open \"/dev/mem\"...\n" );
		return( 1 );
	}
    
	//============================================
    // get virtual addr that maps to physical
	// for light weight AXI bus
	h2p_lw_virtual_base = mmap( NULL, FPGA_LW_SPAN, ( PROT_READ | PROT_WRITE ), MAP_SHARED, fd, FPGA_LW_BASE );	
	if( h2p_lw_virtual_base == MAP_FAILED ) {
		printf( "ERROR: mmap1() failed...\n" );
		close( fd );
		return(1);
	}
	// Get the addresses that map to the two parallel ports on the light-weight bus
	lw_pio_ptr = (unsigned int *)(h2p_lw_virtual_base);
	lw_pio_read_ptr = (unsigned int *)(h2p_lw_virtual_base + FPGA_PIO_READ);
	
	//============================================
	
	// ===========================================
	// get virtual address for
	// AXI bus addr 
	h2p_virtual_base = mmap( NULL, FPGA_AXI_SPAN, ( PROT_READ | PROT_WRITE ), MAP_SHARED, fd, FPGA_AXI_BASE); 	
	if( h2p_virtual_base == MAP_FAILED ) {
		printf( "ERROR: mmap3() failed...\n" );
		close( fd );
		return(1);
	}
    // Get the addresses that map to the two parallel ports on the AXI bus
	axi_pio_ptr =(unsigned int *)(h2p_virtual_base);
	axi_pio_read_ptr =(unsigned int *)(h2p_virtual_base + FPGA_PIO_READ);
	//============================================
	
	
	while(1) 
	{
		int i, N, pio_read, count ;
		int junk; 
		// input a number of transcations to send
		junk = scanf("%d", &N);
		
		count = 0 ;
		// first the AXI bus
		gettimeofday(&t1, NULL);
		// send it N times
		for (i=0; i<N; i++){
			*(axi_pio_ptr) = count ;
			count = *(axi_pio_read_ptr) ;
		}
		gettimeofday(&t2, NULL);
		elapsedTime = (t2.tv_sec - t1.tv_sec) * 1000000.0;      // sec to us
		elapsedTime += (t2.tv_usec - t1.tv_usec) ;   // us to 
		printf("AXI PIO loopback T=%.0f uSec  n/sec=%2.3e\n\r", elapsedTime, N*1e6/elapsedTime);
		printf("count=%d\n\r", count) ;
		
		// now the light-weight bus
		count = 0 ;
		// first the AXI bus
		gettimeofday(&t1, NULL);
		// send it N times
		for (i=0; i<N; i++){
			*(lw_pio_ptr) = count ;
			count = *(lw_pio_read_ptr) ;
		}
		gettimeofday(&t2, NULL);
		elapsedTime = (t2.tv_sec - t1.tv_sec) * 1000000.0;      // sec to us
		elapsedTime += (t2.tv_usec - t1.tv_usec) ;   // us to 
		printf("light-weight PIO loopback T=%.0f uSec  n/sec=%2.3e\n\r", elapsedTime, N*1e6/elapsedTime);
		printf("count=%d\n\r", count) ;
		
		// now the C control time 
		count = 0 ;
		// first the AXI bus
		gettimeofday(&t1, NULL);
		// send it N times
		for (i=0; i<N; i++){
			count = count + 1;
			//count = *(lw_pio_read_ptr) ;
		}
		gettimeofday(&t2, NULL);
		elapsedTime = (t2.tv_sec - t1.tv_sec) * 1000000.0;      // sec to us
		elapsedTime += (t2.tv_usec - t1.tv_usec) ;   // us to 
		printf("light-weight PIO loopback T=%.0f uSec  n/sec=%2.3e\n\r", elapsedTime, N*1e6/elapsedTime);
		printf("count=%d\n\r", count) ;
		
		
	} // end while(1)
} // end main

/// /// ///////////////////////////////////// 
/// end /////////////////////////////////////