1 /*
2  * Combined Ethernet driver for Motorola MPC8xx and MPC82xx.
3  *
4  * Copyright (c) 2003 Intracom S.A.
5  *  by Pantelis Antoniou <panto@intracom.gr>
6  *
7  * 2005 (c) MontaVista Software, Inc.
8  * Vitaly Bordug <vbordug@ru.mvista.com>
9  *
10  * This file is licensed under the terms of the GNU General Public License
11  * version 2. This program is licensed "as is" without any warranty of any
12  * kind, whether express or implied.
13  */
14 
15 #include <linux/module.h>
16 #include <linux/types.h>
17 #include <linux/kernel.h>
18 #include <linux/string.h>
19 #include <linux/ptrace.h>
20 #include <linux/errno.h>
21 #include <linux/ioport.h>
22 #include <linux/slab.h>
23 #include <linux/interrupt.h>
24 #include <linux/delay.h>
25 #include <linux/netdevice.h>
26 #include <linux/etherdevice.h>
27 #include <linux/skbuff.h>
28 #include <linux/spinlock.h>
29 #include <linux/mii.h>
30 #include <linux/ethtool.h>
31 #include <linux/bitops.h>
32 #include <linux/platform_device.h>
33 #include <linux/of_address.h>
34 #include <linux/of_platform.h>
35 #include <linux/pgtable.h>
36 
37 #include <asm/irq.h>
38 #include <linux/uaccess.h>
39 #include <asm/mpc5xxx.h>
40 
41 #include "fs_enet.h"
42 #include "fec.h"
43 
44 /* Make MII read/write commands for the FEC.
45 */
46 #define mk_mii_read(REG)	(0x60020000 | ((REG & 0x1f) << 18))
47 #define mk_mii_write(REG, VAL)	(0x50020000 | ((REG & 0x1f) << 18) | (VAL & 0xffff))
48 #define mk_mii_end		0
49 
50 #define FEC_MII_LOOPS	10000
51 
52 static int fs_enet_fec_mii_read(struct mii_bus *bus , int phy_id, int location)
53 {
54 	struct fec_info* fec = bus->priv;
55 	struct fec __iomem *fecp = fec->fecp;
56 	int i, ret = -1;
57 
58 	BUG_ON((in_be32(&fecp->fec_r_cntrl) & FEC_RCNTRL_MII_MODE) == 0);
59 
60 	/* Add PHY address to register command.  */
61 	out_be32(&fecp->fec_mii_data, (phy_id << 23) | mk_mii_read(location));
62 
63 	for (i = 0; i < FEC_MII_LOOPS; i++)
64 		if ((in_be32(&fecp->fec_ievent) & FEC_ENET_MII) != 0)
65 			break;
66 
67 	if (i < FEC_MII_LOOPS) {
68 		out_be32(&fecp->fec_ievent, FEC_ENET_MII);
69 		ret = in_be32(&fecp->fec_mii_data) & 0xffff;
70 	}
71 
72 	return ret;
73 }
74 
75 static int fs_enet_fec_mii_write(struct mii_bus *bus, int phy_id, int location, u16 val)
76 {
77 	struct fec_info* fec = bus->priv;
78 	struct fec __iomem *fecp = fec->fecp;
79 	int i;
80 
81 	/* this must never happen */
82 	BUG_ON((in_be32(&fecp->fec_r_cntrl) & FEC_RCNTRL_MII_MODE) == 0);
83 
84 	/* Add PHY address to register command.  */
85 	out_be32(&fecp->fec_mii_data, (phy_id << 23) | mk_mii_write(location, val));
86 
87 	for (i = 0; i < FEC_MII_LOOPS; i++)
88 		if ((in_be32(&fecp->fec_ievent) & FEC_ENET_MII) != 0)
89 			break;
90 
91 	if (i < FEC_MII_LOOPS)
92 		out_be32(&fecp->fec_ievent, FEC_ENET_MII);
93 
94 	return 0;
95 
96 }
97 
98 static const struct of_device_id fs_enet_mdio_fec_match[];
99 static int fs_enet_mdio_probe(struct platform_device *ofdev)
100 {
101 	const struct of_device_id *match;
102 	struct resource res;
103 	struct mii_bus *new_bus;
104 	struct fec_info *fec;
105 	int (*get_bus_freq)(struct device_node *);
106 	int ret = -ENOMEM, clock, speed;
107 
108 	match = of_match_device(fs_enet_mdio_fec_match, &ofdev->dev);
109 	if (!match)
110 		return -EINVAL;
111 	get_bus_freq = match->data;
112 
113 	new_bus = mdiobus_alloc();
114 	if (!new_bus)
115 		goto out;
116 
117 	fec = kzalloc(sizeof(struct fec_info), GFP_KERNEL);
118 	if (!fec)
119 		goto out_mii;
120 
121 	new_bus->priv = fec;
122 	new_bus->name = "FEC MII Bus";
123 	new_bus->read = &fs_enet_fec_mii_read;
124 	new_bus->write = &fs_enet_fec_mii_write;
125 
126 	ret = of_address_to_resource(ofdev->dev.of_node, 0, &res);
127 	if (ret)
128 		goto out_res;
129 
130 	snprintf(new_bus->id, MII_BUS_ID_SIZE, "%x", res.start);
131 
132 	fec->fecp = ioremap(res.start, resource_size(&res));
133 	if (!fec->fecp) {
134 		ret = -ENOMEM;
135 		goto out_fec;
136 	}
137 
138 	if (get_bus_freq) {
139 		clock = get_bus_freq(ofdev->dev.of_node);
140 		if (!clock) {
141 			/* Use maximum divider if clock is unknown */
142 			dev_warn(&ofdev->dev, "could not determine IPS clock\n");
143 			clock = 0x3F * 5000000;
144 		}
145 	} else
146 		clock = ppc_proc_freq;
147 
148 	/*
149 	 * Scale for a MII clock <= 2.5 MHz
150 	 * Note that only 6 bits (25:30) are available for MII speed.
151 	 */
152 	speed = (clock + 4999999) / 5000000;
153 	if (speed > 0x3F) {
154 		speed = 0x3F;
155 		dev_err(&ofdev->dev,
156 			"MII clock (%d Hz) exceeds max (2.5 MHz)\n",
157 			clock / speed);
158 	}
159 
160 	fec->mii_speed = speed << 1;
161 
162 	setbits32(&fec->fecp->fec_r_cntrl, FEC_RCNTRL_MII_MODE);
163 	setbits32(&fec->fecp->fec_ecntrl, FEC_ECNTRL_PINMUX |
164 	                                  FEC_ECNTRL_ETHER_EN);
165 	out_be32(&fec->fecp->fec_ievent, FEC_ENET_MII);
166 	clrsetbits_be32(&fec->fecp->fec_mii_speed, 0x7E, fec->mii_speed);
167 
168 	new_bus->phy_mask = ~0;
169 
170 	new_bus->parent = &ofdev->dev;
171 	platform_set_drvdata(ofdev, new_bus);
172 
173 	ret = of_mdiobus_register(new_bus, ofdev->dev.of_node);
174 	if (ret)
175 		goto out_unmap_regs;
176 
177 	return 0;
178 
179 out_unmap_regs:
180 	iounmap(fec->fecp);
181 out_res:
182 out_fec:
183 	kfree(fec);
184 out_mii:
185 	mdiobus_free(new_bus);
186 out:
187 	return ret;
188 }
189 
190 static int fs_enet_mdio_remove(struct platform_device *ofdev)
191 {
192 	struct mii_bus *bus = platform_get_drvdata(ofdev);
193 	struct fec_info *fec = bus->priv;
194 
195 	mdiobus_unregister(bus);
196 	iounmap(fec->fecp);
197 	kfree(fec);
198 	mdiobus_free(bus);
199 
200 	return 0;
201 }
202 
203 static const struct of_device_id fs_enet_mdio_fec_match[] = {
204 	{
205 		.compatible = "fsl,pq1-fec-mdio",
206 	},
207 #if defined(CONFIG_PPC_MPC512x)
208 	{
209 		.compatible = "fsl,mpc5121-fec-mdio",
210 		.data = mpc5xxx_get_bus_frequency,
211 	},
212 #endif
213 	{},
214 };
215 MODULE_DEVICE_TABLE(of, fs_enet_mdio_fec_match);
216 
217 static struct platform_driver fs_enet_fec_mdio_driver = {
218 	.driver = {
219 		.name = "fsl-fec-mdio",
220 		.of_match_table = fs_enet_mdio_fec_match,
221 	},
222 	.probe = fs_enet_mdio_probe,
223 	.remove = fs_enet_mdio_remove,
224 };
225 
226 module_platform_driver(fs_enet_fec_mdio_driver);
227