/*
* Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>.
*
* 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 2 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, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
* You can also choose to distribute this program under the terms of
* the Unmodified Binary Distribution Licence (as given in the file
* COPYING.UBDL), provided that you have satisfied its requirements.
*/
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <ipxe/mii.h>
/** @file
*
* Media Independent Interface
*
*/
/**
* Restart autonegotiation
*
* @v mii MII device
* @ret rc Return status code
*/
int mii_restart ( struct mii_device *mii ) {
int bmcr;
int rc;
/* Read BMCR */
bmcr = mii_read ( mii, MII_BMCR );
if ( bmcr < 0 ) {
rc = bmcr;
DBGC ( mii, "MII %p could not read BMCR: %s\n",
mii, strerror ( rc ) );
return rc;
}
/* Enable and restart autonegotiation */
bmcr |= ( BMCR_ANENABLE | BMCR_ANRESTART );
if ( ( rc = mii_write ( mii, MII_BMCR, bmcr ) ) != 0 ) {
DBGC ( mii, "MII %p could not write BMCR: %s\n",
mii, strerror ( rc ) );
return rc;
}
DBGC ( mii, "MII %p restarted autonegotiation\n", mii );
return 0;
}
/**
* Reset MII device
*
* @v mii MII device
* @ret rc Return status code
*/
int mii_reset ( struct mii_device *mii ) {
unsigned int i;
int bmcr;
int rc;
/* Power-up, enable autonegotiation and initiate reset */
if ( ( rc = mii_write ( mii, MII_BMCR,
( BMCR_RESET | BMCR_ANENABLE ) ) ) != 0 ) {
DBGC ( mii, "MII %p could not write BMCR: %s\n",
mii, strerror ( rc ) );
return rc;
}
/* Wait for reset to complete */
for ( i = 0 ; i < MII_RESET_MAX_WAIT_MS ; i++ ) {
/* Check if reset has completed */
bmcr = mii_read ( mii, MII_BMCR );
if ( bmcr < 0 ) {
rc = bmcr;
DBGC ( mii, "MII %p could not read BMCR: %s\n",
mii, strerror ( rc ) );
return rc;
}
/* If reset is not complete, delay 1ms and retry */
if ( bmcr & BMCR_RESET ) {
mdelay ( 1 );
continue;
}
/* Force autonegotation on again, in case it was
* cleared by the reset.
*/
if ( ( rc = mii_restart ( mii ) ) != 0 )
return rc;
DBGC ( mii, "MII %p reset after %dms\n", mii, i );
return 0;
}
DBGC ( mii, "MII %p timed out waiting for reset\n", mii );
return -ETIMEDOUT;
}
/**
* Update link status via MII
*
* @v mii MII device
* @v netdev Network device
* @ret rc Return status code
*/
int mii_check_link ( struct mii_device *mii, struct net_device *netdev ) {
int bmsr;
int link;
int rc;
/* Read BMSR */
bmsr = mii_read ( mii, MII_BMSR );
if ( bmsr < 0 ) {
rc = bmsr;
return rc;
}
/* Report link status */
link = ( bmsr & BMSR_LSTATUS );
DBGC ( mii, "MII %p link %s (BMSR %#04x)\n",
mii, ( link ? "up" : "down" ), bmsr );
if ( link ) {
netdev_link_up ( netdev );
} else {
netdev_link_down ( netdev );
}
return 0;
}
/**
* Find PHY address
*
* @v mii MII device
* @ret rc Return status code
*/
int mii_find ( struct mii_device *mii ) {
unsigned int address;
int id;
/* Try all possible PHY addresses */
for ( address = 0 ; address <= MII_MAX_PHY_ADDRESS ; address++ ) {
mii->address = address;
id = mii_read ( mii, MII_PHYSID1 );
if ( ( id > 0x0000 ) && ( id < 0xffff ) ) {
DBGC ( mii, "MII %p found PHY at address %d\n",
mii, address );
return 0;
}
}
DBGC ( mii, "MII %p failed to find an address\n", mii );
return -ENOENT;
}
