1 /*
2 * Driver for the MPC5200 Fast Ethernet Controller - MDIO bus driver
3 *
4 * Copyright (C) 2007 Domen Puncer, Telargo, Inc.
5 * Copyright (C) 2008 Wolfram Sang, Pengutronix
6 *
7 * This file is licensed under the terms of the GNU General Public License
8 * version 2. This program is licensed "as is" without any warranty of any
9 * kind, whether express or implied.
10 */
11
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/netdevice.h>
15 #include <linux/phy.h>
16 #include <linux/slab.h>
17 #include <linux/of.h>
18 #include <linux/of_address.h>
19 #include <linux/of_mdio.h>
20 #include <linux/platform_device.h>
21 #include <asm/io.h>
22 #include <asm/mpc52xx.h>
23 #include "fec_mpc52xx.h"
24
25 struct mpc52xx_fec_mdio_priv {
26 struct mpc52xx_fec __iomem *regs;
27 };
28
mpc52xx_fec_mdio_transfer(struct mii_bus * bus,int phy_id,int reg,u32 value)29 static int mpc52xx_fec_mdio_transfer(struct mii_bus *bus, int phy_id,
30 int reg, u32 value)
31 {
32 struct mpc52xx_fec_mdio_priv *priv = bus->priv;
33 struct mpc52xx_fec __iomem *fec = priv->regs;
34 int tries = 3;
35
36 value |= (phy_id << FEC_MII_DATA_PA_SHIFT) & FEC_MII_DATA_PA_MSK;
37 value |= (reg << FEC_MII_DATA_RA_SHIFT) & FEC_MII_DATA_RA_MSK;
38
39 out_be32(&fec->ievent, FEC_IEVENT_MII);
40 out_be32(&fec->mii_data, value);
41
42 /* wait for it to finish, this takes about 23 us on lite5200b */
43 while (!(in_be32(&fec->ievent) & FEC_IEVENT_MII) && --tries)
44 msleep(1);
45
46 if (!tries)
47 return -ETIMEDOUT;
48
49 return value & FEC_MII_DATA_OP_RD ?
50 in_be32(&fec->mii_data) & FEC_MII_DATA_DATAMSK : 0;
51 }
52
mpc52xx_fec_mdio_read(struct mii_bus * bus,int phy_id,int reg)53 static int mpc52xx_fec_mdio_read(struct mii_bus *bus, int phy_id, int reg)
54 {
55 return mpc52xx_fec_mdio_transfer(bus, phy_id, reg, FEC_MII_READ_FRAME);
56 }
57
mpc52xx_fec_mdio_write(struct mii_bus * bus,int phy_id,int reg,u16 data)58 static int mpc52xx_fec_mdio_write(struct mii_bus *bus, int phy_id, int reg,
59 u16 data)
60 {
61 return mpc52xx_fec_mdio_transfer(bus, phy_id, reg,
62 data | FEC_MII_WRITE_FRAME);
63 }
64
mpc52xx_fec_mdio_probe(struct platform_device * of)65 static int mpc52xx_fec_mdio_probe(struct platform_device *of)
66 {
67 struct device *dev = &of->dev;
68 struct device_node *np = of->dev.of_node;
69 struct mii_bus *bus;
70 struct mpc52xx_fec_mdio_priv *priv;
71 struct resource res;
72 int err;
73
74 bus = mdiobus_alloc();
75 if (bus == NULL)
76 return -ENOMEM;
77 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
78 if (priv == NULL) {
79 err = -ENOMEM;
80 goto out_free;
81 }
82
83 bus->name = "mpc52xx MII bus";
84 bus->read = mpc52xx_fec_mdio_read;
85 bus->write = mpc52xx_fec_mdio_write;
86
87 /* setup registers */
88 err = of_address_to_resource(np, 0, &res);
89 if (err)
90 goto out_free;
91 priv->regs = ioremap(res.start, resource_size(&res));
92 if (priv->regs == NULL) {
93 err = -ENOMEM;
94 goto out_free;
95 }
96
97 snprintf(bus->id, MII_BUS_ID_SIZE, "%pa", &res.start);
98 bus->priv = priv;
99
100 bus->parent = dev;
101 dev_set_drvdata(dev, bus);
102
103 /* set MII speed */
104 out_be32(&priv->regs->mii_speed, ((mpc5xxx_get_bus_frequency(dev) >> 20) / 5) << 1);
105
106 err = of_mdiobus_register(bus, np);
107 if (err)
108 goto out_unmap;
109
110 return 0;
111
112 out_unmap:
113 iounmap(priv->regs);
114 out_free:
115 kfree(priv);
116 mdiobus_free(bus);
117
118 return err;
119 }
120
mpc52xx_fec_mdio_remove(struct platform_device * of)121 static void mpc52xx_fec_mdio_remove(struct platform_device *of)
122 {
123 struct mii_bus *bus = platform_get_drvdata(of);
124 struct mpc52xx_fec_mdio_priv *priv = bus->priv;
125
126 mdiobus_unregister(bus);
127 iounmap(priv->regs);
128 kfree(priv);
129 mdiobus_free(bus);
130 }
131
132 static const struct of_device_id mpc52xx_fec_mdio_match[] = {
133 { .compatible = "fsl,mpc5200b-mdio", },
134 { .compatible = "fsl,mpc5200-mdio", },
135 { .compatible = "mpc5200b-fec-phy", },
136 {}
137 };
138 MODULE_DEVICE_TABLE(of, mpc52xx_fec_mdio_match);
139
140 struct platform_driver mpc52xx_fec_mdio_driver = {
141 .driver = {
142 .name = "mpc5200b-fec-phy",
143 .owner = THIS_MODULE,
144 .of_match_table = mpc52xx_fec_mdio_match,
145 },
146 .probe = mpc52xx_fec_mdio_probe,
147 .remove_new = mpc52xx_fec_mdio_remove,
148 };
149
150 /* let fec driver call it, since this has to be registered before it */
151 EXPORT_SYMBOL_GPL(mpc52xx_fec_mdio_driver);
152
153 MODULE_LICENSE("Dual BSD/GPL");
154