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/*

 *

 *  COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994, 1997.

 *  On-Line Applications Research Corporation (OAR).

 *  All rights assigned to U.S. Government, 1994.

 *

 *  This material may be reproduced by or for the U.S. Government pursuant

 *  to the copyright license under the clause at DFARS 252.227-7013.  This

 *  notice must appear in all copies of this file and its derivatives.

 *

 * $ld:

 */

#include <rtems.h>

#include <assert.h>

#include <stdio.h>

#include <bsp.h>

/*

 * Forced delay to get around timing problems with the UNIVERSE chip.  The

 * two nops are used so that the delay works for varying clock frequencies,

 * up to 66 Mhz, with margin.  Each nop averages about 1 1/2 clock ticks,

 * and since there are 2 nops, this routine takes about 3 clock ticks,

 * which on a worst case 66 Mhz board, is 45 nanosecond. This time period

 * is sufficient to guarantee a work-around to the UNIVERSE chip timing

 * problem.  The problem is that when there are two successive accesses to

 * an UNIVERSE register, without sufficient delay, the second access will

 * not work correctly.

 */

void PCI_bus_delay ()

{

  asm(" nop");

  asm(" nop");

}

/*

 * PCI_bus_write

 */

void PCI_bus_write(

  volatile rtems_unsigned32 * _addr,                  /* IN */

  rtems_unsigned32 _data                              /* IN */

)

{

  _data = Convert_Endian_32( _data );

  *_addr = _data;

}

rtems_unsigned32 PCI_bus_read(

  volatile rtems_unsigned32 *  _addr                  /* IN */

)

{

  rtems_unsigned32 data;

  data = *_addr;

  data = Convert_Endian_32( data );

  return data;

}

/*

 * PCI Configuration Cycle Read/Write Access which is used to access all of

 * devices registers on the PCI bus.  i.e.: Universe, Ethernet & PMC.

 */

rtems_unsigned32 Read_pci_device_register(

  rtems_unsigned32 address

)

{

  rtems_unsigned32 data;

  /*

   * Write the PCI configuration address

   */

   PCI_bus_write( (volatile rtems_unsigned32 *)SCORE603E_PCI_IO_CFG_ADDR, address );

  /*

   *  Delay needed when running out of DRAM

   */

   PCI_bus_delay ();

  /*

   * read data

   */

  data = PCI_bus_read( (volatile rtems_unsigned32 *)SCORE603E_PCI_IO_CFG_DATA );

  return data;

}

void  Write_pci_device_register(

  rtems_unsigned32 address,

  rtems_unsigned32 data

)

{

  /*

   * Write the PCI configuration address

   */

   PCI_bus_write( (volatile rtems_unsigned32 *)SCORE603E_PCI_IO_CFG_ADDR, address );

  /*

   *  Delay needed when running out of DRAM

   */

   PCI_bus_delay ();

  /*

   * write data

   */

  PCI_bus_write( (volatile rtems_unsigned32 *)SCORE603E_PCI_IO_CFG_DATA, data );

}