fpga.c

一个开放源码

/* $Id: fpga.c,v 1.2 2000/11/15 17:44:54 apc Exp $ */
/* Copyright 2000  AG Electronics Ltd. */
/* This code is distributed without warranty under the GPL v2 (see COPYING) */

#include <stdio.h>
#include "fpgadata.h"

#define FPGA_INIT 8
#define FPGA_PROG 4
#define FPGA_DONE 2
#define FPGA_BUSY 1

#ifdef DEBUG_FPGA
#define DBG_printf(x) printf x
#else
#define DBG_printf(x)
#endif

int program_fpga (void)
{
    volatile char *fpga = (volatile char *) 0xff300000;
    int i, count;
    volatile unsigned char *fpgactrl = (volatile unsigned char *)0xff000003;
    
    printf("Loading interrupt controller FPGA\n");
    if ((*fpgactrl & FPGA_INIT) != 0)
	DBG_printf (("INIT is presently asserted\n"));
    else
	DBG_printf (("INIT is presently deasserted\n"));


    DBG_printf (("asserting PROGRAM\n"));
    *fpgactrl = FPGA_PROG;

    for (i = 0; i < 100; i++)
	(void) *fpgactrl;

    DBG_printf (("deasserting PROGRAM\n"));
    *fpgactrl = 0;

    if ((*fpgactrl & FPGA_INIT) == 0)
        DBG_printf(("INIT deasserted early\n"));
    DBG_printf (("waiting for INIT to deassert\n"));
    i = 0;
    while ((*fpgactrl & FPGA_INIT) != 0 && i < 100)
	i++;
    if ((*fpgactrl & FPGA_INIT) != 0)
    {
        printf("Failure: FPGA INIT did not deassert\n");
        return -1;
    }
  
    
    DBG_printf (("checking that DONE is deasserted\n"));
    if ((*fpgactrl & FPGA_DONE) != 0)
    {
	printf ("Failure: found FPGA DONE asserted before programming.\n");
        return -1;
    }

    /* do programming */
    DBG_printf (("programming %d bytes...\n",sizeof(fpga_data)));

    count = 0;
    for (i = 0; i < sizeof(fpga_data); i ++)
    {
	if ((count % 4096) == 0)
	    DBG_printf (("%d bytes\n", count));
	count++;

	if ((*fpgactrl & FPGA_DONE) != 0)
	{
	    DBG_printf (("DONE asserted after %d bytes\n", count));
	    break;
	}

	if ((*fpgactrl & FPGA_INIT) != 0)
	    DBG_printf (("INIT asserted after %d bytes.\n", count));

       *fpga = fpga_data[count];
    }
    
    if ((*fpgactrl & FPGA_DONE) == 0)
    {
	DBG_printf (("waiting for DONE assertion\n"));

	while ((*fpgactrl & FPGA_DONE) == 0)
            ;
    }

    DBG_printf (("Done.\n"));
    
    if (fpga[0] == 0xe4 && fpga[1] == 0xfa)
        printf("Interrupt controller loaded, version %d.%d\n",
                fpga[2], fpga[3]);
    else
    {
        printf("Interrupt controller load failed, signature 0x%02x%02x\n",
                fpga[0], fpga[1]);
        return -1;
    }
    
    return 0;
}