xref: /openbmc/linux/drivers/net/dsa/b53/b53_mmap.c (revision 2d96b44f)
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 	u8 __iomem *regs = dev->priv;
34 
35 	*val = readb(regs + (page << 8) + reg);
36 
37 	return 0;
38 }
39 
40 static int b53_mmap_read16(struct b53_device *dev, u8 page, u8 reg, u16 *val)
41 {
42 	u8 __iomem *regs = dev->priv;
43 
44 	if (WARN_ON(reg % 2))
45 		return -EINVAL;
46 
47 	if (dev->pdata && dev->pdata->big_endian)
48 		*val = ioread16be(regs + (page << 8) + reg);
49 	else
50 		*val = readw(regs + (page << 8) + reg);
51 
52 	return 0;
53 }
54 
55 static int b53_mmap_read32(struct b53_device *dev, u8 page, u8 reg, u32 *val)
56 {
57 	u8 __iomem *regs = dev->priv;
58 
59 	if (WARN_ON(reg % 4))
60 		return -EINVAL;
61 
62 	if (dev->pdata && dev->pdata->big_endian)
63 		*val = ioread32be(regs + (page << 8) + reg);
64 	else
65 		*val = readl(regs + (page << 8) + reg);
66 
67 	return 0;
68 }
69 
70 static int b53_mmap_read48(struct b53_device *dev, u8 page, u8 reg, u64 *val)
71 {
72 	u8 __iomem *regs = dev->priv;
73 
74 	if (WARN_ON(reg % 2))
75 		return -EINVAL;
76 
77 	if (reg % 4) {
78 		u16 lo;
79 		u32 hi;
80 
81 		if (dev->pdata && dev->pdata->big_endian) {
82 			lo = ioread16be(regs + (page << 8) + reg);
83 			hi = ioread32be(regs + (page << 8) + reg + 2);
84 		} else {
85 			lo = readw(regs + (page << 8) + reg);
86 			hi = readl(regs + (page << 8) + reg + 2);
87 		}
88 
89 		*val = ((u64)hi << 16) | lo;
90 	} else {
91 		u32 lo;
92 		u16 hi;
93 
94 		if (dev->pdata && dev->pdata->big_endian) {
95 			lo = ioread32be(regs + (page << 8) + reg);
96 			hi = ioread16be(regs + (page << 8) + reg + 4);
97 		} else {
98 			lo = readl(regs + (page << 8) + reg);
99 			hi = readw(regs + (page << 8) + reg + 4);
100 		}
101 
102 		*val = ((u64)hi << 32) | lo;
103 	}
104 
105 	return 0;
106 }
107 
108 static int b53_mmap_read64(struct b53_device *dev, u8 page, u8 reg, u64 *val)
109 {
110 	u8 __iomem *regs = dev->priv;
111 	u32 hi, lo;
112 
113 	if (WARN_ON(reg % 4))
114 		return -EINVAL;
115 
116 	if (dev->pdata && dev->pdata->big_endian) {
117 		lo = ioread32be(regs + (page << 8) + reg);
118 		hi = ioread32be(regs + (page << 8) + reg + 4);
119 	} else {
120 		lo = readl(regs + (page << 8) + reg);
121 		hi = readl(regs + (page << 8) + reg + 4);
122 	}
123 
124 	*val = ((u64)hi << 32) | lo;
125 
126 	return 0;
127 }
128 
129 static int b53_mmap_write8(struct b53_device *dev, u8 page, u8 reg, u8 value)
130 {
131 	u8 __iomem *regs = dev->priv;
132 
133 	writeb(value, regs + (page << 8) + reg);
134 
135 	return 0;
136 }
137 
138 static int b53_mmap_write16(struct b53_device *dev, u8 page, u8 reg,
139 			    u16 value)
140 {
141 	u8 __iomem *regs = dev->priv;
142 
143 	if (WARN_ON(reg % 2))
144 		return -EINVAL;
145 
146 	if (dev->pdata && dev->pdata->big_endian)
147 		iowrite16be(value, regs + (page << 8) + reg);
148 	else
149 		writew(value, regs + (page << 8) + reg);
150 
151 	return 0;
152 }
153 
154 static int b53_mmap_write32(struct b53_device *dev, u8 page, u8 reg,
155 			    u32 value)
156 {
157 	u8 __iomem *regs = dev->priv;
158 
159 	if (WARN_ON(reg % 4))
160 		return -EINVAL;
161 
162 	if (dev->pdata && dev->pdata->big_endian)
163 		iowrite32be(value, regs + (page << 8) + reg);
164 	else
165 		writel(value, regs + (page << 8) + reg);
166 
167 	return 0;
168 }
169 
170 static int b53_mmap_write48(struct b53_device *dev, u8 page, u8 reg,
171 			    u64 value)
172 {
173 	if (WARN_ON(reg % 2))
174 		return -EINVAL;
175 
176 	if (reg % 4) {
177 		u32 hi = (u32)(value >> 16);
178 		u16 lo = (u16)value;
179 
180 		b53_mmap_write16(dev, page, reg, lo);
181 		b53_mmap_write32(dev, page, reg + 2, hi);
182 	} else {
183 		u16 hi = (u16)(value >> 32);
184 		u32 lo = (u32)value;
185 
186 		b53_mmap_write32(dev, page, reg, lo);
187 		b53_mmap_write16(dev, page, reg + 4, hi);
188 	}
189 
190 	return 0;
191 }
192 
193 static int b53_mmap_write64(struct b53_device *dev, u8 page, u8 reg,
194 			    u64 value)
195 {
196 	u32 hi, lo;
197 
198 	hi = upper_32_bits(value);
199 	lo = lower_32_bits(value);
200 
201 	if (WARN_ON(reg % 4))
202 		return -EINVAL;
203 
204 	b53_mmap_write32(dev, page, reg, lo);
205 	b53_mmap_write32(dev, page, reg + 4, hi);
206 
207 	return 0;
208 }
209 
210 static const struct b53_io_ops b53_mmap_ops = {
211 	.read8 = b53_mmap_read8,
212 	.read16 = b53_mmap_read16,
213 	.read32 = b53_mmap_read32,
214 	.read48 = b53_mmap_read48,
215 	.read64 = b53_mmap_read64,
216 	.write8 = b53_mmap_write8,
217 	.write16 = b53_mmap_write16,
218 	.write32 = b53_mmap_write32,
219 	.write48 = b53_mmap_write48,
220 	.write64 = b53_mmap_write64,
221 };
222 
223 static int b53_mmap_probe(struct platform_device *pdev)
224 {
225 	struct b53_platform_data *pdata = pdev->dev.platform_data;
226 	struct b53_device *dev;
227 
228 	if (!pdata)
229 		return -EINVAL;
230 
231 	dev = b53_switch_alloc(&pdev->dev, &b53_mmap_ops, pdata->regs);
232 	if (!dev)
233 		return -ENOMEM;
234 
235 	dev->pdata = pdata;
236 
237 	platform_set_drvdata(pdev, dev);
238 
239 	return b53_switch_register(dev);
240 }
241 
242 static int b53_mmap_remove(struct platform_device *pdev)
243 {
244 	struct b53_device *dev = platform_get_drvdata(pdev);
245 
246 	if (dev)
247 		b53_switch_remove(dev);
248 
249 	return 0;
250 }
251 
252 static const struct of_device_id b53_mmap_of_table[] = {
253 	{ .compatible = "brcm,bcm3384-switch" },
254 	{ .compatible = "brcm,bcm6328-switch" },
255 	{ .compatible = "brcm,bcm6368-switch" },
256 	{ .compatible = "brcm,bcm63xx-switch" },
257 	{ /* sentinel */ },
258 };
259 
260 static struct platform_driver b53_mmap_driver = {
261 	.probe = b53_mmap_probe,
262 	.remove = b53_mmap_remove,
263 	.driver = {
264 		.name = "b53-switch",
265 		.of_match_table = b53_mmap_of_table,
266 	},
267 };
268 
269 module_platform_driver(b53_mmap_driver);
270 MODULE_AUTHOR("Jonas Gorski <jogo@openwrt.org>");
271 MODULE_DESCRIPTION("B53 MMAP access driver");
272 MODULE_LICENSE("Dual BSD/GPL");
273