1 /*
2
3 mii.c: MII interface library
4
5 Ported to gPXE by Daniel Verkamp <daniel@drv.nu>
6 from Linux drivers/net/mii.c
7
8 Maintained by Jeff Garzik <jgarzik@pobox.com>
9 Copyright 2001,2002 Jeff Garzik
10
11 Various code came from myson803.c and other files by
12 Donald Becker. Copyright:
13
14 Written 1998-2002 by Donald Becker.
15
16 This software may be used and distributed according
17 to the terms of the GNU General Public License (GPL),
18 incorporated herein by reference. Drivers based on
19 or derived from this code fall under the GPL and must
20 retain the authorship, copyright and license notice.
21 This file is not a complete program and may only be
22 used when the entire operating system is licensed
23 under the GPL.
24
25 The author may be reached as becker@scyld.com, or C/O
26 Scyld Computing Corporation
27 410 Severn Ave., Suite 210
28 Annapolis MD 21403
29
30 */
31
32 #include <mii.h>
33
34 /**
35 * mii_link_ok - is link status up/ok
36 * @mii: the MII interface
37 *
38 * Returns 1 if the MII reports link status up/ok, 0 otherwise.
39 */
40 int
mii_link_ok(struct mii_if_info * mii)41 mii_link_ok ( struct mii_if_info *mii )
42 {
43 /* first, a dummy read, needed to latch some MII phys */
44 mii->mdio_read ( mii->dev, mii->phy_id, MII_BMSR );
45 if ( mii->mdio_read ( mii->dev, mii->phy_id, MII_BMSR ) & BMSR_LSTATUS )
46 return 1;
47 return 0;
48 }
49
50 /**
51 * mii_check_link - check MII link status
52 * @mii: MII interface
53 *
54 * If the link status changed (previous != current), call
55 * netif_carrier_on() if current link status is Up or call
56 * netif_carrier_off() if current link status is Down.
57 */
58 void
mii_check_link(struct mii_if_info * mii)59 mii_check_link ( struct mii_if_info *mii )
60 {
61 int cur_link = mii_link_ok ( mii );
62 int prev_link = netdev_link_ok ( mii->dev );
63
64 if ( cur_link && !prev_link )
65 netdev_link_up ( mii->dev );
66 else if (prev_link && !cur_link)
67 netdev_link_down ( mii->dev );
68 }
69
70
71 /**
72 * mii_check_media - check the MII interface for a duplex change
73 * @mii: the MII interface
74 * @ok_to_print: OK to print link up/down messages
75 * @init_media: OK to save duplex mode in @mii
76 *
77 * Returns 1 if the duplex mode changed, 0 if not.
78 * If the media type is forced, always returns 0.
79 */
80 unsigned int
mii_check_media(struct mii_if_info * mii,unsigned int ok_to_print,unsigned int init_media)81 mii_check_media ( struct mii_if_info *mii,
82 unsigned int ok_to_print,
83 unsigned int init_media )
84 {
85 unsigned int old_carrier, new_carrier;
86 int advertise, lpa, media, duplex;
87 int lpa2 = 0;
88
89 /* if forced media, go no further */
90 if (mii->force_media)
91 return 0; /* duplex did not change */
92
93 /* check current and old link status */
94 old_carrier = netdev_link_ok ( mii->dev ) ? 1 : 0;
95 new_carrier = (unsigned int) mii_link_ok ( mii );
96
97 /* if carrier state did not change, this is a "bounce",
98 * just exit as everything is already set correctly
99 */
100 if ( ( ! init_media ) && ( old_carrier == new_carrier ) )
101 return 0; /* duplex did not change */
102
103 /* no carrier, nothing much to do */
104 if ( ! new_carrier ) {
105 netdev_link_down ( mii->dev );
106 if ( ok_to_print )
107 DBG ( "%s: link down\n", mii->dev->name);
108 return 0; /* duplex did not change */
109 }
110
111 /*
112 * we have carrier, see who's on the other end
113 */
114 netdev_link_up ( mii->dev );
115
116 /* get MII advertise and LPA values */
117 if ( ( ! init_media ) && ( mii->advertising ) ) {
118 advertise = mii->advertising;
119 } else {
120 advertise = mii->mdio_read ( mii->dev, mii->phy_id, MII_ADVERTISE );
121 mii->advertising = advertise;
122 }
123 lpa = mii->mdio_read ( mii->dev, mii->phy_id, MII_LPA );
124 if ( mii->supports_gmii )
125 lpa2 = mii->mdio_read ( mii->dev, mii->phy_id, MII_STAT1000 );
126
127 /* figure out media and duplex from advertise and LPA values */
128 media = mii_nway_result ( lpa & advertise );
129 duplex = ( media & ADVERTISE_FULL ) ? 1 : 0;
130 if ( lpa2 & LPA_1000FULL )
131 duplex = 1;
132
133 if ( ok_to_print )
134 DBG ( "%s: link up, %sMbps, %s-duplex, lpa 0x%04X\n",
135 mii->dev->name,
136 lpa2 & ( LPA_1000FULL | LPA_1000HALF ) ? "1000" :
137 media & ( ADVERTISE_100FULL | ADVERTISE_100HALF ) ? "100" : "10",
138 duplex ? "full" : "half",
139 lpa);
140
141 if ( ( init_media ) || ( mii->full_duplex != duplex ) ) {
142 mii->full_duplex = duplex;
143 return 1; /* duplex changed */
144 }
145
146 return 0; /* duplex did not change */
147 }
148