Commit | Line | Data |
---|---|---|
ddc24ae1 AP |
1 | /* |
2 | * Copyright (C) 2015 Broadcom Corporation | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public License as | |
6 | * published by the Free Software Foundation version 2. | |
7 | * | |
8 | * This program is distributed "as is" WITHOUT ANY WARRANTY of any | |
9 | * kind, whether express or implied; without even the implied warranty | |
10 | * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
11 | * GNU General Public License for more details. | |
12 | */ | |
13 | ||
14 | #include <linux/delay.h> | |
15 | #include <linux/io.h> | |
16 | #include <linux/kernel.h> | |
17 | #include <linux/module.h> | |
18 | #include <linux/of.h> | |
19 | #include <linux/of_platform.h> | |
20 | #include <linux/of_mdio.h> | |
21 | #include <linux/phy.h> | |
22 | #include <linux/platform_device.h> | |
23 | #include <linux/sched.h> | |
24 | ||
25 | #define IPROC_GPHY_MDCDIV 0x1a | |
26 | ||
27 | #define MII_CTRL_OFFSET 0x000 | |
28 | ||
29 | #define MII_CTRL_DIV_SHIFT 0 | |
30 | #define MII_CTRL_PRE_SHIFT 7 | |
31 | #define MII_CTRL_BUSY_SHIFT 8 | |
32 | ||
33 | #define MII_DATA_OFFSET 0x004 | |
34 | #define MII_DATA_MASK 0xffff | |
35 | #define MII_DATA_TA_SHIFT 16 | |
36 | #define MII_DATA_TA_VAL 2 | |
37 | #define MII_DATA_RA_SHIFT 18 | |
38 | #define MII_DATA_PA_SHIFT 23 | |
39 | #define MII_DATA_OP_SHIFT 28 | |
40 | #define MII_DATA_OP_WRITE 1 | |
41 | #define MII_DATA_OP_READ 2 | |
42 | #define MII_DATA_SB_SHIFT 30 | |
43 | ||
44 | struct iproc_mdio_priv { | |
45 | struct mii_bus *mii_bus; | |
46 | void __iomem *base; | |
47 | }; | |
48 | ||
49 | static inline int iproc_mdio_wait_for_idle(void __iomem *base) | |
50 | { | |
51 | u32 val; | |
52 | unsigned int timeout = 1000; /* loop for 1s */ | |
53 | ||
54 | do { | |
55 | val = readl(base + MII_CTRL_OFFSET); | |
56 | if ((val & BIT(MII_CTRL_BUSY_SHIFT)) == 0) | |
57 | return 0; | |
58 | ||
59 | usleep_range(1000, 2000); | |
60 | } while (timeout--); | |
61 | ||
62 | return -ETIMEDOUT; | |
63 | } | |
64 | ||
65 | static inline void iproc_mdio_config_clk(void __iomem *base) | |
66 | { | |
67 | u32 val; | |
68 | ||
69 | val = (IPROC_GPHY_MDCDIV << MII_CTRL_DIV_SHIFT) | | |
70 | BIT(MII_CTRL_PRE_SHIFT); | |
71 | writel(val, base + MII_CTRL_OFFSET); | |
72 | } | |
73 | ||
74 | static int iproc_mdio_read(struct mii_bus *bus, int phy_id, int reg) | |
75 | { | |
76 | struct iproc_mdio_priv *priv = bus->priv; | |
77 | u32 cmd; | |
78 | int rc; | |
79 | ||
80 | rc = iproc_mdio_wait_for_idle(priv->base); | |
81 | if (rc) | |
82 | return rc; | |
83 | ||
84 | iproc_mdio_config_clk(priv->base); | |
85 | ||
86 | /* Prepare the read operation */ | |
87 | cmd = (MII_DATA_TA_VAL << MII_DATA_TA_SHIFT) | | |
88 | (reg << MII_DATA_RA_SHIFT) | | |
89 | (phy_id << MII_DATA_PA_SHIFT) | | |
90 | BIT(MII_DATA_SB_SHIFT) | | |
91 | (MII_DATA_OP_READ << MII_DATA_OP_SHIFT); | |
92 | ||
93 | writel(cmd, priv->base + MII_DATA_OFFSET); | |
94 | ||
95 | rc = iproc_mdio_wait_for_idle(priv->base); | |
96 | if (rc) | |
97 | return rc; | |
98 | ||
99 | cmd = readl(priv->base + MII_DATA_OFFSET) & MII_DATA_MASK; | |
100 | ||
101 | return cmd; | |
102 | } | |
103 | ||
104 | static int iproc_mdio_write(struct mii_bus *bus, int phy_id, | |
105 | int reg, u16 val) | |
106 | { | |
107 | struct iproc_mdio_priv *priv = bus->priv; | |
108 | u32 cmd; | |
109 | int rc; | |
110 | ||
111 | rc = iproc_mdio_wait_for_idle(priv->base); | |
112 | if (rc) | |
113 | return rc; | |
114 | ||
115 | iproc_mdio_config_clk(priv->base); | |
116 | ||
117 | /* Prepare the write operation */ | |
118 | cmd = (MII_DATA_TA_VAL << MII_DATA_TA_SHIFT) | | |
119 | (reg << MII_DATA_RA_SHIFT) | | |
120 | (phy_id << MII_DATA_PA_SHIFT) | | |
121 | BIT(MII_DATA_SB_SHIFT) | | |
122 | (MII_DATA_OP_WRITE << MII_DATA_OP_SHIFT) | | |
123 | ((u32)(val) & MII_DATA_MASK); | |
124 | ||
125 | writel(cmd, priv->base + MII_DATA_OFFSET); | |
126 | ||
127 | rc = iproc_mdio_wait_for_idle(priv->base); | |
128 | if (rc) | |
129 | return rc; | |
130 | ||
131 | return 0; | |
132 | } | |
133 | ||
134 | static int iproc_mdio_probe(struct platform_device *pdev) | |
135 | { | |
136 | struct iproc_mdio_priv *priv; | |
137 | struct mii_bus *bus; | |
138 | struct resource *res; | |
139 | int rc; | |
140 | ||
141 | priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); | |
142 | if (!priv) | |
143 | return -ENOMEM; | |
144 | ||
145 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
146 | priv->base = devm_ioremap_resource(&pdev->dev, res); | |
147 | if (IS_ERR(priv->base)) { | |
148 | dev_err(&pdev->dev, "failed to ioremap register\n"); | |
149 | return PTR_ERR(priv->base); | |
150 | } | |
151 | ||
152 | priv->mii_bus = mdiobus_alloc(); | |
153 | if (!priv->mii_bus) { | |
154 | dev_err(&pdev->dev, "MDIO bus alloc failed\n"); | |
155 | return -ENOMEM; | |
156 | } | |
157 | ||
158 | bus = priv->mii_bus; | |
159 | bus->priv = priv; | |
160 | bus->name = "iProc MDIO bus"; | |
161 | snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d", pdev->name, pdev->id); | |
162 | bus->parent = &pdev->dev; | |
163 | bus->read = iproc_mdio_read; | |
164 | bus->write = iproc_mdio_write; | |
165 | ||
166 | rc = of_mdiobus_register(bus, pdev->dev.of_node); | |
167 | if (rc) { | |
168 | dev_err(&pdev->dev, "MDIO bus registration failed\n"); | |
169 | goto err_iproc_mdio; | |
170 | } | |
171 | ||
172 | platform_set_drvdata(pdev, priv); | |
173 | ||
174 | dev_info(&pdev->dev, "Broadcom iProc MDIO bus at 0x%p\n", priv->base); | |
175 | ||
176 | return 0; | |
177 | ||
178 | err_iproc_mdio: | |
179 | mdiobus_free(bus); | |
180 | return rc; | |
181 | } | |
182 | ||
183 | static int iproc_mdio_remove(struct platform_device *pdev) | |
184 | { | |
185 | struct iproc_mdio_priv *priv = platform_get_drvdata(pdev); | |
186 | ||
187 | mdiobus_unregister(priv->mii_bus); | |
188 | mdiobus_free(priv->mii_bus); | |
189 | ||
190 | return 0; | |
191 | } | |
192 | ||
193 | static const struct of_device_id iproc_mdio_of_match[] = { | |
194 | { .compatible = "brcm,iproc-mdio", }, | |
195 | { /* sentinel */ }, | |
196 | }; | |
197 | MODULE_DEVICE_TABLE(of, iproc_mdio_of_match); | |
198 | ||
199 | static struct platform_driver iproc_mdio_driver = { | |
200 | .driver = { | |
201 | .name = "iproc-mdio", | |
202 | .of_match_table = iproc_mdio_of_match, | |
203 | }, | |
204 | .probe = iproc_mdio_probe, | |
205 | .remove = iproc_mdio_remove, | |
206 | }; | |
207 | ||
208 | module_platform_driver(iproc_mdio_driver); | |
209 | ||
210 | MODULE_AUTHOR("Broadcom Corporation"); | |
211 | MODULE_DESCRIPTION("Broadcom iProc MDIO bus controller"); | |
212 | MODULE_LICENSE("GPL v2"); | |
213 | MODULE_ALIAS("platform:iproc-mdio"); |