xref: /openbmc/u-boot/common/miiphyutil.c (revision 2262cfee)
1 /*
2  * (C) Copyright 2001
3  * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
4  *
5  * See file CREDITS for list of people who contributed to this
6  * project.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21  * MA 02111-1307 USA
22  */
23 
24 /*
25  * This provides a bit-banged interface to the ethernet MII management
26  * channel.
27  */
28 
29 #include <common.h>
30 #include <miiphy.h>
31 
32 #if defined(CONFIG_MII) || (CONFIG_COMMANDS & CFG_CMD_MII)
33 
34 /*****************************************************************************
35  *
36  * Read the OUI, manufacture's model number, and revision number.
37  *
38  * OUI:     22 bits (unsigned int)
39  * Model:    6 bits (unsigned char)
40  * Revision: 4 bits (unsigned char)
41  *
42  * Returns:
43  *   0 on success
44  */
45 int miiphy_info (unsigned char addr,
46 		 unsigned int *oui,
47 		 unsigned char *model, unsigned char *rev)
48 {
49 	unsigned int reg = 0;
50 
51 	/*
52 	 * Trick: we are reading two 16 registers into a 32 bit variable
53 	 * so we do a 16 read into the high order bits of the variable (big
54 	 * endian, you know), shift it down 16 bits, and the read the rest.
55 	 */
56 	if (miiphy_read (addr, PHY_PHYIDR2, (unsigned short *) &reg) != 0) {
57 #ifdef DEBUG
58 		printf ("PHY ID register 2 read failed\n");
59 #endif
60 		return (-1);
61 	}
62 	reg >>= 16;
63 
64 #ifdef DEBUG
65 	printf ("PHY_PHYIDR2 @ 0x%x = 0x%04x\n", addr, reg);
66 #endif
67 	if (reg == 0xFFFF) {
68 		/* No physical device present at this address */
69 		return (-1);
70 	}
71 
72 	if (miiphy_read (addr, PHY_PHYIDR1, (unsigned short *) &reg) != 0) {
73 #ifdef DEBUG
74 		printf ("PHY ID register 1 read failed\n");
75 #endif
76 		return (-1);
77 	}
78 #ifdef DEBUG
79 	printf ("PHY_PHYIDR[1,2] @ 0x%x = 0x%08x\n", addr, reg);
80 #endif
81 	*oui   =                 ( reg >> 10);
82 	*model = (unsigned char) ((reg >>  4) & 0x0000003F);
83 	*rev   = (unsigned char) ( reg        & 0x0000000F);
84 	return (0);
85 }
86 
87 
88 /*****************************************************************************
89  *
90  * Reset the PHY.
91  * Returns:
92  *   0 on success
93  */
94 int miiphy_reset (unsigned char addr)
95 {
96 	unsigned short reg;
97 	int loop_cnt;
98 
99 	if (miiphy_write (addr, PHY_BMCR, 0x8000) != 0) {
100 #ifdef DEBUG
101 		printf ("PHY reset failed\n");
102 #endif
103 		return (-1);
104 	}
105 
106 	/*
107 	 * Poll the control register for the reset bit to go to 0 (it is
108 	 * auto-clearing).  This should happen within 0.5 seconds per the
109 	 * IEEE spec.
110 	 */
111 	loop_cnt = 0;
112 	reg = 0x8000;
113 	while (((reg & 0x8000) != 0) && (loop_cnt++ < 1000000)) {
114 		if (miiphy_read (addr, PHY_BMCR, &reg) != 0) {
115 #     ifdef DEBUG
116 			printf ("PHY status read failed\n");
117 #     endif
118 			return (-1);
119 		}
120 	}
121 	if ((reg & 0x8000) == 0) {
122 		return (0);
123 	} else {
124 		printf ("PHY reset timed out\n");
125 		return (-1);
126 	}
127 	return (0);
128 }
129 
130 
131 /*****************************************************************************
132  *
133  * Determine the ethernet speed (10/100).
134  */
135 int miiphy_speed (unsigned char addr)
136 {
137 	unsigned short reg;
138 
139 	if (miiphy_read (addr, PHY_ANLPAR, &reg)) {
140 		printf ("PHY speed1 read failed, assuming 10bT\n");
141 		return (_10BASET);
142 	}
143 
144 	if ((reg & PHY_ANLPAR_100) != 0) {
145 		return (_100BASET);
146 	} else {
147 		return (_10BASET);
148 	}
149 }
150 
151 
152 /*****************************************************************************
153  *
154  * Determine full/half duplex.
155  */
156 int miiphy_duplex (unsigned char addr)
157 {
158 	unsigned short reg;
159 
160 	if (miiphy_read (addr, PHY_ANLPAR, &reg)) {
161 		printf ("PHY duplex read failed, assuming half duplex\n");
162 		return (HALF);
163 	}
164 
165 	if ((reg & (PHY_ANLPAR_10FD | PHY_ANLPAR_TXFD)) != 0) {
166 		return (FULL);
167 	} else {
168 		return (HALF);
169 	}
170 }
171 
172 #endif /* CONFIG_MII || (CONFIG_COMMANDS & CFG_CMD_MII) */
173