From 1f80b2dcd5b889875ac40a11bf15b88b0dffc330 Mon Sep 17 00:00:00 2001 From: Daniel Verkamp Date: Wed, 10 Dec 2008 02:35:02 -0600 Subject: [PATCH] [ethernet] Add MII link status functions from Linux Signed-off-by: Michael Brown --- src/include/mii.h | 59 +++++++++++++++++++ src/net/mii.c | 147 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 206 insertions(+) create mode 100644 src/net/mii.c diff --git a/src/include/mii.h b/src/include/mii.h index 05c54f09..3b735d99 100755 --- a/src/include/mii.h +++ b/src/include/mii.h @@ -157,4 +157,63 @@ struct mii_if_info { void (*mdio_write) (struct net_device *dev, int phy_id, int location, int val); }; + +extern int mii_link_ok (struct mii_if_info *mii); +extern void mii_check_link (struct mii_if_info *mii); +extern unsigned int mii_check_media (struct mii_if_info *mii, + unsigned int ok_to_print, + unsigned int init_media); + + +/** + * mii_nway_result + * @negotiated: value of MII ANAR and'd with ANLPAR + * + * Given a set of MII abilities, check each bit and returns the + * currently supported media, in the priority order defined by + * IEEE 802.3u. We use LPA_xxx constants but note this is not the + * value of LPA solely, as described above. + * + * The one exception to IEEE 802.3u is that 100baseT4 is placed + * between 100T-full and 100T-half. If your phy does not support + * 100T4 this is fine. If your phy places 100T4 elsewhere in the + * priority order, you will need to roll your own function. + */ +static inline unsigned int mii_nway_result (unsigned int negotiated) +{ + unsigned int ret; + + if (negotiated & LPA_100FULL) + ret = LPA_100FULL; + else if (negotiated & LPA_100BASE4) + ret = LPA_100BASE4; + else if (negotiated & LPA_100HALF) + ret = LPA_100HALF; + else if (negotiated & LPA_10FULL) + ret = LPA_10FULL; + else + ret = LPA_10HALF; + + return ret; +} + +/** + * mii_duplex + * @duplex_lock: Non-zero if duplex is locked at full + * @negotiated: value of MII ANAR and'd with ANLPAR + * + * A small helper function for a common case. Returns one + * if the media is operating or locked at full duplex, and + * returns zero otherwise. + */ +static inline unsigned int mii_duplex (unsigned int duplex_lock, + unsigned int negotiated) +{ + if (duplex_lock) + return 1; + if (mii_nway_result(negotiated) & LPA_DUPLEX) + return 1; + return 0; +} + #endif diff --git a/src/net/mii.c b/src/net/mii.c new file mode 100644 index 00000000..0de64428 --- /dev/null +++ b/src/net/mii.c @@ -0,0 +1,147 @@ +/* + + mii.c: MII interface library + + Ported to gPXE by Daniel Verkamp + from Linux drivers/net/mii.c + + Maintained by Jeff Garzik + Copyright 2001,2002 Jeff Garzik + + Various code came from myson803.c and other files by + Donald Becker. Copyright: + + Written 1998-2002 by Donald Becker. + + This software may be used and distributed according + to the terms of the GNU General Public License (GPL), + incorporated herein by reference. Drivers based on + or derived from this code fall under the GPL and must + retain the authorship, copyright and license notice. + This file is not a complete program and may only be + used when the entire operating system is licensed + under the GPL. + + The author may be reached as becker@scyld.com, or C/O + Scyld Computing Corporation + 410 Severn Ave., Suite 210 + Annapolis MD 21403 + +*/ + +#include + +/** + * mii_link_ok - is link status up/ok + * @mii: the MII interface + * + * Returns 1 if the MII reports link status up/ok, 0 otherwise. + */ +int +mii_link_ok ( struct mii_if_info *mii ) +{ + /* first, a dummy read, needed to latch some MII phys */ + mii->mdio_read ( mii->dev, mii->phy_id, MII_BMSR ); + if ( mii->mdio_read ( mii->dev, mii->phy_id, MII_BMSR ) & BMSR_LSTATUS ) + return 1; + return 0; +} + +/** + * mii_check_link - check MII link status + * @mii: MII interface + * + * If the link status changed (previous != current), call + * netif_carrier_on() if current link status is Up or call + * netif_carrier_off() if current link status is Down. + */ +void +mii_check_link ( struct mii_if_info *mii ) +{ + int cur_link = mii_link_ok ( mii ); + int prev_link = netdev_link_ok ( mii->dev ); + + if ( cur_link && !prev_link ) + netdev_link_up ( mii->dev ); + else if (prev_link && !cur_link) + netdev_link_down ( mii->dev ); +} + + +/** + * mii_check_media - check the MII interface for a duplex change + * @mii: the MII interface + * @ok_to_print: OK to print link up/down messages + * @init_media: OK to save duplex mode in @mii + * + * Returns 1 if the duplex mode changed, 0 if not. + * If the media type is forced, always returns 0. + */ +unsigned int +mii_check_media ( struct mii_if_info *mii, + unsigned int ok_to_print, + unsigned int init_media ) +{ + unsigned int old_carrier, new_carrier; + int advertise, lpa, media, duplex; + int lpa2 = 0; + + /* if forced media, go no further */ + if (mii->force_media) + return 0; /* duplex did not change */ + + /* check current and old link status */ + old_carrier = netdev_link_ok ( mii->dev ) ? 1 : 0; + new_carrier = (unsigned int) mii_link_ok ( mii ); + + /* if carrier state did not change, this is a "bounce", + * just exit as everything is already set correctly + */ + if ( ( ! init_media ) && ( old_carrier == new_carrier ) ) + return 0; /* duplex did not change */ + + /* no carrier, nothing much to do */ + if ( ! new_carrier ) { + netdev_link_down ( mii->dev ); + if ( ok_to_print ) + DBG ( "%s: link down\n", mii->dev->name); + return 0; /* duplex did not change */ + } + + /* + * we have carrier, see who's on the other end + */ + netdev_link_up ( mii->dev ); + + /* get MII advertise and LPA values */ + if ( ( ! init_media ) && ( mii->advertising ) ) { + advertise = mii->advertising; + } else { + advertise = mii->mdio_read ( mii->dev, mii->phy_id, MII_ADVERTISE ); + mii->advertising = advertise; + } + lpa = mii->mdio_read ( mii->dev, mii->phy_id, MII_LPA ); + if ( mii->supports_gmii ) + lpa2 = mii->mdio_read ( mii->dev, mii->phy_id, MII_STAT1000 ); + + /* figure out media and duplex from advertise and LPA values */ + media = mii_nway_result ( lpa & advertise ); + duplex = ( media & ADVERTISE_FULL ) ? 1 : 0; + if ( lpa2 & LPA_1000FULL ) + duplex = 1; + + if ( ok_to_print ) + DBG ( "%s: link up, %sMbps, %s-duplex, lpa 0x%04X\n", + mii->dev->name, + lpa2 & ( LPA_1000FULL | LPA_1000HALF ) ? "1000" : + media & ( ADVERTISE_100FULL | ADVERTISE_100HALF ) ? "100" : "10", + duplex ? "full" : "half", + lpa); + + if ( ( init_media ) || ( mii->full_duplex != duplex ) ) { + mii->full_duplex = duplex; + return 1; /* duplex changed */ + } + + return 0; /* duplex did not change */ +}