xref: /openbmc/linux/drivers/net/dsa/b53/b53_mmap.c (revision b830f94f)
1 /*
2  * B53 register access through memory mapped registers
3  *
4  * Copyright (C) 2012-2013 Jonas Gorski <jogo@openwrt.org>
5  *
6  * Permission to use, copy, modify, and/or distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/io.h>
22 #include <linux/platform_device.h>
23 #include <linux/platform_data/b53.h>
24 
25 #include "b53_priv.h"
26 
27 struct b53_mmap_priv {
28 	void __iomem *regs;
29 };
30 
31 static int b53_mmap_read8(struct b53_device *dev, u8 page, u8 reg, u8 *val)
32 {
33 	struct b53_mmap_priv *priv = dev->priv;
34 	void __iomem *regs = priv->regs;
35 
36 	*val = readb(regs + (page << 8) + reg);
37 
38 	return 0;
39 }
40 
41 static int b53_mmap_read16(struct b53_device *dev, u8 page, u8 reg, u16 *val)
42 {
43 	struct b53_mmap_priv *priv = dev->priv;
44 	void __iomem *regs = priv->regs;
45 
46 	if (WARN_ON(reg % 2))
47 		return -EINVAL;
48 
49 	if (dev->pdata && dev->pdata->big_endian)
50 		*val = ioread16be(regs + (page << 8) + reg);
51 	else
52 		*val = readw(regs + (page << 8) + reg);
53 
54 	return 0;
55 }
56 
57 static int b53_mmap_read32(struct b53_device *dev, u8 page, u8 reg, u32 *val)
58 {
59 	struct b53_mmap_priv *priv = dev->priv;
60 	void __iomem *regs = priv->regs;
61 
62 	if (WARN_ON(reg % 4))
63 		return -EINVAL;
64 
65 	if (dev->pdata && dev->pdata->big_endian)
66 		*val = ioread32be(regs + (page << 8) + reg);
67 	else
68 		*val = readl(regs + (page << 8) + reg);
69 
70 	return 0;
71 }
72 
73 static int b53_mmap_read48(struct b53_device *dev, u8 page, u8 reg, u64 *val)
74 {
75 	struct b53_mmap_priv *priv = dev->priv;
76 	void __iomem *regs = priv->regs;
77 
78 	if (WARN_ON(reg % 2))
79 		return -EINVAL;
80 
81 	if (reg % 4) {
82 		u16 lo;
83 		u32 hi;
84 
85 		if (dev->pdata && dev->pdata->big_endian) {
86 			lo = ioread16be(regs + (page << 8) + reg);
87 			hi = ioread32be(regs + (page << 8) + reg + 2);
88 		} else {
89 			lo = readw(regs + (page << 8) + reg);
90 			hi = readl(regs + (page << 8) + reg + 2);
91 		}
92 
93 		*val = ((u64)hi << 16) | lo;
94 	} else {
95 		u32 lo;
96 		u16 hi;
97 
98 		if (dev->pdata && dev->pdata->big_endian) {
99 			lo = ioread32be(regs + (page << 8) + reg);
100 			hi = ioread16be(regs + (page << 8) + reg + 4);
101 		} else {
102 			lo = readl(regs + (page << 8) + reg);
103 			hi = readw(regs + (page << 8) + reg + 4);
104 		}
105 
106 		*val = ((u64)hi << 32) | lo;
107 	}
108 
109 	return 0;
110 }
111 
112 static int b53_mmap_read64(struct b53_device *dev, u8 page, u8 reg, u64 *val)
113 {
114 	struct b53_mmap_priv *priv = dev->priv;
115 	void __iomem *regs = priv->regs;
116 	u32 hi, lo;
117 
118 	if (WARN_ON(reg % 4))
119 		return -EINVAL;
120 
121 	if (dev->pdata && dev->pdata->big_endian) {
122 		lo = ioread32be(regs + (page << 8) + reg);
123 		hi = ioread32be(regs + (page << 8) + reg + 4);
124 	} else {
125 		lo = readl(regs + (page << 8) + reg);
126 		hi = readl(regs + (page << 8) + reg + 4);
127 	}
128 
129 	*val = ((u64)hi << 32) | lo;
130 
131 	return 0;
132 }
133 
134 static int b53_mmap_write8(struct b53_device *dev, u8 page, u8 reg, u8 value)
135 {
136 	struct b53_mmap_priv *priv = dev->priv;
137 	void __iomem *regs = priv->regs;
138 
139 	writeb(value, regs + (page << 8) + reg);
140 
141 	return 0;
142 }
143 
144 static int b53_mmap_write16(struct b53_device *dev, u8 page, u8 reg,
145 			    u16 value)
146 {
147 	struct b53_mmap_priv *priv = dev->priv;
148 	void __iomem *regs = priv->regs;
149 
150 	if (WARN_ON(reg % 2))
151 		return -EINVAL;
152 
153 	if (dev->pdata && dev->pdata->big_endian)
154 		iowrite16be(value, regs + (page << 8) + reg);
155 	else
156 		writew(value, regs + (page << 8) + reg);
157 
158 	return 0;
159 }
160 
161 static int b53_mmap_write32(struct b53_device *dev, u8 page, u8 reg,
162 			    u32 value)
163 {
164 	struct b53_mmap_priv *priv = dev->priv;
165 	void __iomem *regs = priv->regs;
166 
167 	if (WARN_ON(reg % 4))
168 		return -EINVAL;
169 
170 	if (dev->pdata && dev->pdata->big_endian)
171 		iowrite32be(value, regs + (page << 8) + reg);
172 	else
173 		writel(value, regs + (page << 8) + reg);
174 
175 	return 0;
176 }
177 
178 static int b53_mmap_write48(struct b53_device *dev, u8 page, u8 reg,
179 			    u64 value)
180 {
181 	if (WARN_ON(reg % 2))
182 		return -EINVAL;
183 
184 	if (reg % 4) {
185 		u32 hi = (u32)(value >> 16);
186 		u16 lo = (u16)value;
187 
188 		b53_mmap_write16(dev, page, reg, lo);
189 		b53_mmap_write32(dev, page, reg + 2, hi);
190 	} else {
191 		u16 hi = (u16)(value >> 32);
192 		u32 lo = (u32)value;
193 
194 		b53_mmap_write32(dev, page, reg, lo);
195 		b53_mmap_write16(dev, page, reg + 4, hi);
196 	}
197 
198 	return 0;
199 }
200 
201 static int b53_mmap_write64(struct b53_device *dev, u8 page, u8 reg,
202 			    u64 value)
203 {
204 	u32 hi, lo;
205 
206 	hi = upper_32_bits(value);
207 	lo = lower_32_bits(value);
208 
209 	if (WARN_ON(reg % 4))
210 		return -EINVAL;
211 
212 	b53_mmap_write32(dev, page, reg, lo);
213 	b53_mmap_write32(dev, page, reg + 4, hi);
214 
215 	return 0;
216 }
217 
218 static const struct b53_io_ops b53_mmap_ops = {
219 	.read8 = b53_mmap_read8,
220 	.read16 = b53_mmap_read16,
221 	.read32 = b53_mmap_read32,
222 	.read48 = b53_mmap_read48,
223 	.read64 = b53_mmap_read64,
224 	.write8 = b53_mmap_write8,
225 	.write16 = b53_mmap_write16,
226 	.write32 = b53_mmap_write32,
227 	.write48 = b53_mmap_write48,
228 	.write64 = b53_mmap_write64,
229 };
230 
231 static int b53_mmap_probe(struct platform_device *pdev)
232 {
233 	struct b53_platform_data *pdata = pdev->dev.platform_data;
234 	struct b53_mmap_priv *priv;
235 	struct b53_device *dev;
236 
237 	if (!pdata)
238 		return -EINVAL;
239 
240 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
241 	if (!priv)
242 		return -ENOMEM;
243 
244 	priv->regs = pdata->regs;
245 
246 	dev = b53_switch_alloc(&pdev->dev, &b53_mmap_ops, priv);
247 	if (!dev)
248 		return -ENOMEM;
249 
250 	dev->pdata = pdata;
251 
252 	platform_set_drvdata(pdev, dev);
253 
254 	return b53_switch_register(dev);
255 }
256 
257 static int b53_mmap_remove(struct platform_device *pdev)
258 {
259 	struct b53_device *dev = platform_get_drvdata(pdev);
260 
261 	if (dev)
262 		b53_switch_remove(dev);
263 
264 	return 0;
265 }
266 
267 static const struct of_device_id b53_mmap_of_table[] = {
268 	{ .compatible = "brcm,bcm3384-switch" },
269 	{ .compatible = "brcm,bcm6328-switch" },
270 	{ .compatible = "brcm,bcm6368-switch" },
271 	{ .compatible = "brcm,bcm63xx-switch" },
272 	{ /* sentinel */ },
273 };
274 MODULE_DEVICE_TABLE(of, b53_mmap_of_table);
275 
276 static struct platform_driver b53_mmap_driver = {
277 	.probe = b53_mmap_probe,
278 	.remove = b53_mmap_remove,
279 	.driver = {
280 		.name = "b53-switch",
281 		.of_match_table = b53_mmap_of_table,
282 	},
283 };
284 
285 module_platform_driver(b53_mmap_driver);
286 MODULE_AUTHOR("Jonas Gorski <jogo@openwrt.org>");
287 MODULE_DESCRIPTION("B53 MMAP access driver");
288 MODULE_LICENSE("Dual BSD/GPL");
289