/* Ethernet Physical Receiver model.

   Copyright (C) 2010-2018 Free Software Foundation, Inc.

   Contributed by Analog Devices, Inc.

   This file is part of simulators.

   This program is free software; you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include "config.h"

#include "sim-main.h"

#include "devices.h"

#if defined (HAVE_LINUX_MII_H) && defined (HAVE_LINUX_TYPES_H)

/* Workaround old/broken linux headers.  */

#include <linux/types.h>

#include <linux/mii.h>

#define REG_PHY_SIZE 0x20

struct eth_phy

{

  bu32 base;

  bu16 regs[REG_PHY_SIZE];

};

#define reg_base()      offsetof(struct eth_phy, regs[0])

#define reg_offset(reg) (offsetof(struct eth_phy, reg) - reg_base())

#define reg_idx(reg)    (reg_offset (reg) / 4)

static const char * const reg_names[] =

{

  [MII_BMCR       ] = "MII_BMCR",

  [MII_BMSR       ] = "MII_BMSR",

  [MII_PHYSID1    ] = "MII_PHYSID1",

  [MII_PHYSID2    ] = "MII_PHYSID2",

  [MII_ADVERTISE  ] = "MII_ADVERTISE",

  [MII_LPA        ] = "MII_LPA",

  [MII_EXPANSION  ] = "MII_EXPANSION",

#ifdef MII_CTRL1000

  [MII_CTRL1000   ] = "MII_CTRL1000",

#endif

#ifdef MII_STAT1000

  [MII_STAT1000   ] = "MII_STAT1000",

#endif

#ifdef MII_ESTATUS

  [MII_ESTATUS    ] = "MII_ESTATUS",

#endif

  [MII_DCOUNTER   ] = "MII_DCOUNTER",

  [MII_FCSCOUNTER ] = "MII_FCSCOUNTER",

  [MII_NWAYTEST   ] = "MII_NWAYTEST",

  [MII_RERRCOUNTER] = "MII_RERRCOUNTER",

  [MII_SREVISION  ] = "MII_SREVISION",

  [MII_RESV1      ] = "MII_RESV1",

  [MII_LBRERROR   ] = "MII_LBRERROR",

  [MII_PHYADDR    ] = "MII_PHYADDR",

  [MII_RESV2      ] = "MII_RESV2",

  [MII_TPISTATUS  ] = "MII_TPISTATUS",

  [MII_NCONFIG    ] = "MII_NCONFIG",

};

#define mmr_name(off) (reg_names[off] ? : "<INV>")

#define mmr_off reg_off

static unsigned

eth_phy_io_write_buffer (struct hw *me, const void *source,

			 int space, address_word addr, unsigned nr_bytes)

{

  struct eth_phy *phy = hw_data (me);

  bu16 reg_off;

  bu16 value;

  bu16 *valuep;

  value = dv_load_2 (source);

  reg_off = addr - phy->base;

  valuep = (void *)((unsigned long)phy + reg_base() + reg_off);

  HW_TRACE_WRITE ();

  switch (reg_off)

    {

    case MII_BMCR:

      *valuep = value;

      break;

    case MII_PHYSID1:

    case MII_PHYSID2:

      /* Discard writes to these.  */

      break;

    default:

      /* XXX: Discard writes to unknown regs ?  */

      *valuep = value;

      break;

    }

  return nr_bytes;

}

static unsigned

eth_phy_io_read_buffer (struct hw *me, void *dest,

			int space, address_word addr, unsigned nr_bytes)

{

  struct eth_phy *phy = hw_data (me);

  bu16 reg_off;

  bu16 *valuep;

  reg_off = addr - phy->base;

  valuep = (void *)((unsigned long)phy + reg_base() + reg_off);

  HW_TRACE_READ ();

  switch (reg_off)

    {

    case MII_BMCR:

      dv_store_2 (dest, *valuep);

      break;

    case MII_BMSR:

      /* XXX: Let people control this ?  */

      *valuep = BMSR_100FULL | BMSR_100HALF | BMSR_10FULL | BMSR_10HALF |

		BMSR_ANEGCOMPLETE | BMSR_ANEGCAPABLE | BMSR_LSTATUS;

      dv_store_2 (dest, *valuep);

      break;

    case MII_LPA:

      /* XXX: Let people control this ?  */

      *valuep = LPA_100FULL | LPA_100HALF | LPA_10FULL | LPA_10HALF;

      dv_store_2 (dest, *valuep);

      break;

    default:

      dv_store_2 (dest, *valuep);

      break;

    }

  return nr_bytes;

}

static void

attach_eth_phy_regs (struct hw *me, struct eth_phy *phy)

{

  address_word attach_address;

  int attach_space;

  unsigned attach_size;

  reg_property_spec reg;

  if (hw_find_property (me, "reg") == NULL)

    hw_abort (me, "Missing \"reg\" property");

  if (!hw_find_reg_array_property (me, "reg", 0, &reg))

    hw_abort (me, "\"reg\" property must contain three addr/size entries");

  hw_unit_address_to_attach_address (hw_parent (me),

				     &reg.address,

				     &attach_space, &attach_address, me);

  hw_unit_size_to_attach_size (hw_parent (me), &reg.size, &attach_size, me);

  if (attach_size != REG_PHY_SIZE)

    hw_abort (me, "\"reg\" size must be %#x", REG_PHY_SIZE);

  hw_attach_address (hw_parent (me),

		     0, attach_space, attach_address, attach_size, me);

  phy->base = attach_address;

}

static void

eth_phy_finish (struct hw *me)

{

  struct eth_phy *phy;

  phy = HW_ZALLOC (me, struct eth_phy);

  set_hw_data (me, phy);

  set_hw_io_read_buffer (me, eth_phy_io_read_buffer);

  set_hw_io_write_buffer (me, eth_phy_io_write_buffer);

  attach_eth_phy_regs (me, phy);

  /* Initialize the PHY.  */

  phy->regs[MII_PHYSID1] = 0;    /* Unassigned Vendor */

  phy->regs[MII_PHYSID2] = 0xAD; /* Product */

}

#else

static void

eth_phy_finish (struct hw *me)

{

  HW_TRACE ((me, "No linux/mii.h support found"));

}

#endif

const struct hw_descriptor dv_eth_phy_descriptor[] =

{

  {"eth_phy", eth_phy_finish,},

  {NULL, NULL},

};