xref: /openbmc/linux/drivers/net/dsa/b53/b53_mmap.c (revision 75020f2d)
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/bits.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/io.h>
23 #include <linux/platform_device.h>
24 #include <linux/platform_data/b53.h>
25 
26 #include "b53_priv.h"
27 
28 struct b53_mmap_priv {
29 	void __iomem *regs;
30 };
31 
32 static int b53_mmap_read8(struct b53_device *dev, u8 page, u8 reg, u8 *val)
33 {
34 	struct b53_mmap_priv *priv = dev->priv;
35 	void __iomem *regs = priv->regs;
36 
37 	*val = readb(regs + (page << 8) + reg);
38 
39 	return 0;
40 }
41 
42 static int b53_mmap_read16(struct b53_device *dev, u8 page, u8 reg, u16 *val)
43 {
44 	struct b53_mmap_priv *priv = dev->priv;
45 	void __iomem *regs = priv->regs;
46 
47 	if (WARN_ON(reg % 2))
48 		return -EINVAL;
49 
50 	if (dev->pdata && dev->pdata->big_endian)
51 		*val = ioread16be(regs + (page << 8) + reg);
52 	else
53 		*val = readw(regs + (page << 8) + reg);
54 
55 	return 0;
56 }
57 
58 static int b53_mmap_read32(struct b53_device *dev, u8 page, u8 reg, u32 *val)
59 {
60 	struct b53_mmap_priv *priv = dev->priv;
61 	void __iomem *regs = priv->regs;
62 
63 	if (WARN_ON(reg % 4))
64 		return -EINVAL;
65 
66 	if (dev->pdata && dev->pdata->big_endian)
67 		*val = ioread32be(regs + (page << 8) + reg);
68 	else
69 		*val = readl(regs + (page << 8) + reg);
70 
71 	return 0;
72 }
73 
74 static int b53_mmap_read48(struct b53_device *dev, u8 page, u8 reg, u64 *val)
75 {
76 	struct b53_mmap_priv *priv = dev->priv;
77 	void __iomem *regs = priv->regs;
78 
79 	if (WARN_ON(reg % 2))
80 		return -EINVAL;
81 
82 	if (reg % 4) {
83 		u16 lo;
84 		u32 hi;
85 
86 		if (dev->pdata && dev->pdata->big_endian) {
87 			lo = ioread16be(regs + (page << 8) + reg);
88 			hi = ioread32be(regs + (page << 8) + reg + 2);
89 		} else {
90 			lo = readw(regs + (page << 8) + reg);
91 			hi = readl(regs + (page << 8) + reg + 2);
92 		}
93 
94 		*val = ((u64)hi << 16) | lo;
95 	} else {
96 		u32 lo;
97 		u16 hi;
98 
99 		if (dev->pdata && dev->pdata->big_endian) {
100 			lo = ioread32be(regs + (page << 8) + reg);
101 			hi = ioread16be(regs + (page << 8) + reg + 4);
102 		} else {
103 			lo = readl(regs + (page << 8) + reg);
104 			hi = readw(regs + (page << 8) + reg + 4);
105 		}
106 
107 		*val = ((u64)hi << 32) | lo;
108 	}
109 
110 	return 0;
111 }
112 
113 static int b53_mmap_read64(struct b53_device *dev, u8 page, u8 reg, u64 *val)
114 {
115 	struct b53_mmap_priv *priv = dev->priv;
116 	void __iomem *regs = priv->regs;
117 	u32 hi, lo;
118 
119 	if (WARN_ON(reg % 4))
120 		return -EINVAL;
121 
122 	if (dev->pdata && dev->pdata->big_endian) {
123 		lo = ioread32be(regs + (page << 8) + reg);
124 		hi = ioread32be(regs + (page << 8) + reg + 4);
125 	} else {
126 		lo = readl(regs + (page << 8) + reg);
127 		hi = readl(regs + (page << 8) + reg + 4);
128 	}
129 
130 	*val = ((u64)hi << 32) | lo;
131 
132 	return 0;
133 }
134 
135 static int b53_mmap_write8(struct b53_device *dev, u8 page, u8 reg, u8 value)
136 {
137 	struct b53_mmap_priv *priv = dev->priv;
138 	void __iomem *regs = priv->regs;
139 
140 	writeb(value, regs + (page << 8) + reg);
141 
142 	return 0;
143 }
144 
145 static int b53_mmap_write16(struct b53_device *dev, u8 page, u8 reg,
146 			    u16 value)
147 {
148 	struct b53_mmap_priv *priv = dev->priv;
149 	void __iomem *regs = priv->regs;
150 
151 	if (WARN_ON(reg % 2))
152 		return -EINVAL;
153 
154 	if (dev->pdata && dev->pdata->big_endian)
155 		iowrite16be(value, regs + (page << 8) + reg);
156 	else
157 		writew(value, regs + (page << 8) + reg);
158 
159 	return 0;
160 }
161 
162 static int b53_mmap_write32(struct b53_device *dev, u8 page, u8 reg,
163 			    u32 value)
164 {
165 	struct b53_mmap_priv *priv = dev->priv;
166 	void __iomem *regs = priv->regs;
167 
168 	if (WARN_ON(reg % 4))
169 		return -EINVAL;
170 
171 	if (dev->pdata && dev->pdata->big_endian)
172 		iowrite32be(value, regs + (page << 8) + reg);
173 	else
174 		writel(value, regs + (page << 8) + reg);
175 
176 	return 0;
177 }
178 
179 static int b53_mmap_write48(struct b53_device *dev, u8 page, u8 reg,
180 			    u64 value)
181 {
182 	if (WARN_ON(reg % 2))
183 		return -EINVAL;
184 
185 	if (reg % 4) {
186 		u32 hi = (u32)(value >> 16);
187 		u16 lo = (u16)value;
188 
189 		b53_mmap_write16(dev, page, reg, lo);
190 		b53_mmap_write32(dev, page, reg + 2, hi);
191 	} else {
192 		u16 hi = (u16)(value >> 32);
193 		u32 lo = (u32)value;
194 
195 		b53_mmap_write32(dev, page, reg, lo);
196 		b53_mmap_write16(dev, page, reg + 4, hi);
197 	}
198 
199 	return 0;
200 }
201 
202 static int b53_mmap_write64(struct b53_device *dev, u8 page, u8 reg,
203 			    u64 value)
204 {
205 	u32 hi, lo;
206 
207 	hi = upper_32_bits(value);
208 	lo = lower_32_bits(value);
209 
210 	if (WARN_ON(reg % 4))
211 		return -EINVAL;
212 
213 	b53_mmap_write32(dev, page, reg, lo);
214 	b53_mmap_write32(dev, page, reg + 4, hi);
215 
216 	return 0;
217 }
218 
219 static const struct b53_io_ops b53_mmap_ops = {
220 	.read8 = b53_mmap_read8,
221 	.read16 = b53_mmap_read16,
222 	.read32 = b53_mmap_read32,
223 	.read48 = b53_mmap_read48,
224 	.read64 = b53_mmap_read64,
225 	.write8 = b53_mmap_write8,
226 	.write16 = b53_mmap_write16,
227 	.write32 = b53_mmap_write32,
228 	.write48 = b53_mmap_write48,
229 	.write64 = b53_mmap_write64,
230 };
231 
232 static int b53_mmap_probe_of(struct platform_device *pdev,
233 			     struct b53_platform_data **ppdata)
234 {
235 	struct device_node *np = pdev->dev.of_node;
236 	struct device_node *of_ports, *of_port;
237 	struct device *dev = &pdev->dev;
238 	struct b53_platform_data *pdata;
239 	void __iomem *mem;
240 
241 	mem = devm_platform_ioremap_resource(pdev, 0);
242 	if (IS_ERR(mem))
243 		return PTR_ERR(mem);
244 
245 	pdata = devm_kzalloc(dev, sizeof(struct b53_platform_data),
246 			     GFP_KERNEL);
247 	if (!pdata)
248 		return -ENOMEM;
249 
250 	pdata->regs = mem;
251 	pdata->chip_id = BCM63XX_DEVICE_ID;
252 	pdata->big_endian = of_property_read_bool(np, "big-endian");
253 
254 	of_ports = of_get_child_by_name(np, "ports");
255 	if (!of_ports) {
256 		dev_err(dev, "no ports child node found\n");
257 		return -EINVAL;
258 	}
259 
260 	for_each_available_child_of_node(of_ports, of_port) {
261 		u32 reg;
262 
263 		if (of_property_read_u32(of_port, "reg", &reg))
264 			continue;
265 
266 		if (reg < B53_CPU_PORT)
267 			pdata->enabled_ports |= BIT(reg);
268 	}
269 
270 	of_node_put(of_ports);
271 	*ppdata = pdata;
272 
273 	return 0;
274 }
275 
276 static int b53_mmap_probe(struct platform_device *pdev)
277 {
278 	struct device_node *np = pdev->dev.of_node;
279 	struct b53_platform_data *pdata = pdev->dev.platform_data;
280 	struct b53_mmap_priv *priv;
281 	struct b53_device *dev;
282 	int ret;
283 
284 	if (!pdata && np) {
285 		ret = b53_mmap_probe_of(pdev, &pdata);
286 		if (ret) {
287 			dev_err(&pdev->dev, "OF probe error\n");
288 			return ret;
289 		}
290 	}
291 
292 	if (!pdata)
293 		return -EINVAL;
294 
295 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
296 	if (!priv)
297 		return -ENOMEM;
298 
299 	priv->regs = pdata->regs;
300 
301 	dev = b53_switch_alloc(&pdev->dev, &b53_mmap_ops, priv);
302 	if (!dev)
303 		return -ENOMEM;
304 
305 	dev->pdata = pdata;
306 
307 	platform_set_drvdata(pdev, dev);
308 
309 	return b53_switch_register(dev);
310 }
311 
312 static int b53_mmap_remove(struct platform_device *pdev)
313 {
314 	struct b53_device *dev = platform_get_drvdata(pdev);
315 
316 	if (dev)
317 		b53_switch_remove(dev);
318 
319 	return 0;
320 }
321 
322 static const struct of_device_id b53_mmap_of_table[] = {
323 	{ .compatible = "brcm,bcm3384-switch" },
324 	{ .compatible = "brcm,bcm6328-switch" },
325 	{ .compatible = "brcm,bcm6368-switch" },
326 	{ .compatible = "brcm,bcm63xx-switch" },
327 	{ /* sentinel */ },
328 };
329 MODULE_DEVICE_TABLE(of, b53_mmap_of_table);
330 
331 static struct platform_driver b53_mmap_driver = {
332 	.probe = b53_mmap_probe,
333 	.remove = b53_mmap_remove,
334 	.driver = {
335 		.name = "b53-switch",
336 		.of_match_table = b53_mmap_of_table,
337 	},
338 };
339 
340 module_platform_driver(b53_mmap_driver);
341 MODULE_AUTHOR("Jonas Gorski <jogo@openwrt.org>");
342 MODULE_DESCRIPTION("B53 MMAP access driver");
343 MODULE_LICENSE("Dual BSD/GPL");
344