xref: /openbmc/linux/drivers/net/dsa/b53/b53_srab.c (revision 4f6cce39)
1 /*
2  * B53 register access through Switch Register Access Bridge Registers
3  *
4  * Copyright (C) 2013 Hauke Mehrtens <hauke@hauke-m.de>
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/delay.h>
22 #include <linux/platform_device.h>
23 #include <linux/platform_data/b53.h>
24 #include <linux/of.h>
25 
26 #include "b53_priv.h"
27 
28 /* command and status register of the SRAB */
29 #define B53_SRAB_CMDSTAT		0x2c
30 #define  B53_SRAB_CMDSTAT_RST		BIT(2)
31 #define  B53_SRAB_CMDSTAT_WRITE		BIT(1)
32 #define  B53_SRAB_CMDSTAT_GORDYN	BIT(0)
33 #define  B53_SRAB_CMDSTAT_PAGE		24
34 #define  B53_SRAB_CMDSTAT_REG		16
35 
36 /* high order word of write data to switch registe */
37 #define B53_SRAB_WD_H			0x30
38 
39 /* low order word of write data to switch registe */
40 #define B53_SRAB_WD_L			0x34
41 
42 /* high order word of read data from switch register */
43 #define B53_SRAB_RD_H			0x38
44 
45 /* low order word of read data from switch register */
46 #define B53_SRAB_RD_L			0x3c
47 
48 /* command and status register of the SRAB */
49 #define B53_SRAB_CTRLS			0x40
50 #define  B53_SRAB_CTRLS_RCAREQ		BIT(3)
51 #define  B53_SRAB_CTRLS_RCAGNT		BIT(4)
52 #define  B53_SRAB_CTRLS_SW_INIT_DONE	BIT(6)
53 
54 /* the register captures interrupt pulses from the switch */
55 #define B53_SRAB_INTR			0x44
56 #define  B53_SRAB_INTR_P(x)		BIT(x)
57 #define  B53_SRAB_SWITCH_PHY		BIT(8)
58 #define  B53_SRAB_1588_SYNC		BIT(9)
59 #define  B53_SRAB_IMP1_SLEEP_TIMER	BIT(10)
60 #define  B53_SRAB_P7_SLEEP_TIMER	BIT(11)
61 #define  B53_SRAB_IMP0_SLEEP_TIMER	BIT(12)
62 
63 struct b53_srab_priv {
64 	void __iomem *regs;
65 };
66 
67 static int b53_srab_request_grant(struct b53_device *dev)
68 {
69 	struct b53_srab_priv *priv = dev->priv;
70 	u8 __iomem *regs = priv->regs;
71 	u32 ctrls;
72 	int i;
73 
74 	ctrls = readl(regs + B53_SRAB_CTRLS);
75 	ctrls |= B53_SRAB_CTRLS_RCAREQ;
76 	writel(ctrls, regs + B53_SRAB_CTRLS);
77 
78 	for (i = 0; i < 20; i++) {
79 		ctrls = readl(regs + B53_SRAB_CTRLS);
80 		if (ctrls & B53_SRAB_CTRLS_RCAGNT)
81 			break;
82 		usleep_range(10, 100);
83 	}
84 	if (WARN_ON(i == 5))
85 		return -EIO;
86 
87 	return 0;
88 }
89 
90 static void b53_srab_release_grant(struct b53_device *dev)
91 {
92 	struct b53_srab_priv *priv = dev->priv;
93 	u8 __iomem *regs = priv->regs;
94 	u32 ctrls;
95 
96 	ctrls = readl(regs + B53_SRAB_CTRLS);
97 	ctrls &= ~B53_SRAB_CTRLS_RCAREQ;
98 	writel(ctrls, regs + B53_SRAB_CTRLS);
99 }
100 
101 static int b53_srab_op(struct b53_device *dev, u8 page, u8 reg, u32 op)
102 {
103 	struct b53_srab_priv *priv = dev->priv;
104 	u8 __iomem *regs = priv->regs;
105 	int i;
106 	u32 cmdstat;
107 
108 	/* set register address */
109 	cmdstat = (page << B53_SRAB_CMDSTAT_PAGE) |
110 		  (reg << B53_SRAB_CMDSTAT_REG) |
111 		  B53_SRAB_CMDSTAT_GORDYN |
112 		  op;
113 	writel(cmdstat, regs + B53_SRAB_CMDSTAT);
114 
115 	/* check if operation completed */
116 	for (i = 0; i < 5; ++i) {
117 		cmdstat = readl(regs + B53_SRAB_CMDSTAT);
118 		if (!(cmdstat & B53_SRAB_CMDSTAT_GORDYN))
119 			break;
120 		usleep_range(10, 100);
121 	}
122 
123 	if (WARN_ON(i == 5))
124 		return -EIO;
125 
126 	return 0;
127 }
128 
129 static int b53_srab_read8(struct b53_device *dev, u8 page, u8 reg, u8 *val)
130 {
131 	struct b53_srab_priv *priv = dev->priv;
132 	u8 __iomem *regs = priv->regs;
133 	int ret = 0;
134 
135 	ret = b53_srab_request_grant(dev);
136 	if (ret)
137 		goto err;
138 
139 	ret = b53_srab_op(dev, page, reg, 0);
140 	if (ret)
141 		goto err;
142 
143 	*val = readl(regs + B53_SRAB_RD_L) & 0xff;
144 
145 err:
146 	b53_srab_release_grant(dev);
147 
148 	return ret;
149 }
150 
151 static int b53_srab_read16(struct b53_device *dev, u8 page, u8 reg, u16 *val)
152 {
153 	struct b53_srab_priv *priv = dev->priv;
154 	u8 __iomem *regs = priv->regs;
155 	int ret = 0;
156 
157 	ret = b53_srab_request_grant(dev);
158 	if (ret)
159 		goto err;
160 
161 	ret = b53_srab_op(dev, page, reg, 0);
162 	if (ret)
163 		goto err;
164 
165 	*val = readl(regs + B53_SRAB_RD_L) & 0xffff;
166 
167 err:
168 	b53_srab_release_grant(dev);
169 
170 	return ret;
171 }
172 
173 static int b53_srab_read32(struct b53_device *dev, u8 page, u8 reg, u32 *val)
174 {
175 	struct b53_srab_priv *priv = dev->priv;
176 	u8 __iomem *regs = priv->regs;
177 	int ret = 0;
178 
179 	ret = b53_srab_request_grant(dev);
180 	if (ret)
181 		goto err;
182 
183 	ret = b53_srab_op(dev, page, reg, 0);
184 	if (ret)
185 		goto err;
186 
187 	*val = readl(regs + B53_SRAB_RD_L);
188 
189 err:
190 	b53_srab_release_grant(dev);
191 
192 	return ret;
193 }
194 
195 static int b53_srab_read48(struct b53_device *dev, u8 page, u8 reg, u64 *val)
196 {
197 	struct b53_srab_priv *priv = dev->priv;
198 	u8 __iomem *regs = priv->regs;
199 	int ret = 0;
200 
201 	ret = b53_srab_request_grant(dev);
202 	if (ret)
203 		goto err;
204 
205 	ret = b53_srab_op(dev, page, reg, 0);
206 	if (ret)
207 		goto err;
208 
209 	*val = readl(regs + B53_SRAB_RD_L);
210 	*val += ((u64)readl(regs + B53_SRAB_RD_H) & 0xffff) << 32;
211 
212 err:
213 	b53_srab_release_grant(dev);
214 
215 	return ret;
216 }
217 
218 static int b53_srab_read64(struct b53_device *dev, u8 page, u8 reg, u64 *val)
219 {
220 	struct b53_srab_priv *priv = dev->priv;
221 	u8 __iomem *regs = priv->regs;
222 	int ret = 0;
223 
224 	ret = b53_srab_request_grant(dev);
225 	if (ret)
226 		goto err;
227 
228 	ret = b53_srab_op(dev, page, reg, 0);
229 	if (ret)
230 		goto err;
231 
232 	*val = readl(regs + B53_SRAB_RD_L);
233 	*val += (u64)readl(regs + B53_SRAB_RD_H) << 32;
234 
235 err:
236 	b53_srab_release_grant(dev);
237 
238 	return ret;
239 }
240 
241 static int b53_srab_write8(struct b53_device *dev, u8 page, u8 reg, u8 value)
242 {
243 	struct b53_srab_priv *priv = dev->priv;
244 	u8 __iomem *regs = priv->regs;
245 	int ret = 0;
246 
247 	ret = b53_srab_request_grant(dev);
248 	if (ret)
249 		goto err;
250 
251 	writel(value, regs + B53_SRAB_WD_L);
252 
253 	ret = b53_srab_op(dev, page, reg, B53_SRAB_CMDSTAT_WRITE);
254 
255 err:
256 	b53_srab_release_grant(dev);
257 
258 	return ret;
259 }
260 
261 static int b53_srab_write16(struct b53_device *dev, u8 page, u8 reg,
262 			    u16 value)
263 {
264 	struct b53_srab_priv *priv = dev->priv;
265 	u8 __iomem *regs = priv->regs;
266 	int ret = 0;
267 
268 	ret = b53_srab_request_grant(dev);
269 	if (ret)
270 		goto err;
271 
272 	writel(value, regs + B53_SRAB_WD_L);
273 
274 	ret = b53_srab_op(dev, page, reg, B53_SRAB_CMDSTAT_WRITE);
275 
276 err:
277 	b53_srab_release_grant(dev);
278 
279 	return ret;
280 }
281 
282 static int b53_srab_write32(struct b53_device *dev, u8 page, u8 reg,
283 			    u32 value)
284 {
285 	struct b53_srab_priv *priv = dev->priv;
286 	u8 __iomem *regs = priv->regs;
287 	int ret = 0;
288 
289 	ret = b53_srab_request_grant(dev);
290 	if (ret)
291 		goto err;
292 
293 	writel(value, regs + B53_SRAB_WD_L);
294 
295 	ret = b53_srab_op(dev, page, reg, B53_SRAB_CMDSTAT_WRITE);
296 
297 err:
298 	b53_srab_release_grant(dev);
299 
300 	return ret;
301 }
302 
303 static int b53_srab_write48(struct b53_device *dev, u8 page, u8 reg,
304 			    u64 value)
305 {
306 	struct b53_srab_priv *priv = dev->priv;
307 	u8 __iomem *regs = priv->regs;
308 	int ret = 0;
309 
310 	ret = b53_srab_request_grant(dev);
311 	if (ret)
312 		goto err;
313 
314 	writel((u32)value, regs + B53_SRAB_WD_L);
315 	writel((u16)(value >> 32), regs + B53_SRAB_WD_H);
316 
317 	ret = b53_srab_op(dev, page, reg, B53_SRAB_CMDSTAT_WRITE);
318 
319 err:
320 	b53_srab_release_grant(dev);
321 
322 	return ret;
323 }
324 
325 static int b53_srab_write64(struct b53_device *dev, u8 page, u8 reg,
326 			    u64 value)
327 {
328 	struct b53_srab_priv *priv = dev->priv;
329 	u8 __iomem *regs = priv->regs;
330 	int ret = 0;
331 
332 	ret = b53_srab_request_grant(dev);
333 	if (ret)
334 		goto err;
335 
336 	writel((u32)value, regs + B53_SRAB_WD_L);
337 	writel((u32)(value >> 32), regs + B53_SRAB_WD_H);
338 
339 	ret = b53_srab_op(dev, page, reg, B53_SRAB_CMDSTAT_WRITE);
340 
341 err:
342 	b53_srab_release_grant(dev);
343 
344 	return ret;
345 }
346 
347 static const struct b53_io_ops b53_srab_ops = {
348 	.read8 = b53_srab_read8,
349 	.read16 = b53_srab_read16,
350 	.read32 = b53_srab_read32,
351 	.read48 = b53_srab_read48,
352 	.read64 = b53_srab_read64,
353 	.write8 = b53_srab_write8,
354 	.write16 = b53_srab_write16,
355 	.write32 = b53_srab_write32,
356 	.write48 = b53_srab_write48,
357 	.write64 = b53_srab_write64,
358 };
359 
360 static const struct of_device_id b53_srab_of_match[] = {
361 	{ .compatible = "brcm,bcm53010-srab" },
362 	{ .compatible = "brcm,bcm53011-srab" },
363 	{ .compatible = "brcm,bcm53012-srab" },
364 	{ .compatible = "brcm,bcm53018-srab" },
365 	{ .compatible = "brcm,bcm53019-srab" },
366 	{ .compatible = "brcm,bcm5301x-srab" },
367 	{ .compatible = "brcm,bcm58522-srab", .data = (void *)BCM58XX_DEVICE_ID },
368 	{ .compatible = "brcm,bcm58525-srab", .data = (void *)BCM58XX_DEVICE_ID },
369 	{ .compatible = "brcm,bcm58535-srab", .data = (void *)BCM58XX_DEVICE_ID },
370 	{ .compatible = "brcm,bcm58622-srab", .data = (void *)BCM58XX_DEVICE_ID },
371 	{ .compatible = "brcm,bcm58623-srab", .data = (void *)BCM58XX_DEVICE_ID },
372 	{ .compatible = "brcm,bcm58625-srab", .data = (void *)BCM58XX_DEVICE_ID },
373 	{ .compatible = "brcm,bcm88312-srab", .data = (void *)BCM58XX_DEVICE_ID },
374 	{ .compatible = "brcm,nsp-srab", .data = (void *)BCM58XX_DEVICE_ID },
375 	{ /* sentinel */ },
376 };
377 MODULE_DEVICE_TABLE(of, b53_srab_of_match);
378 
379 static int b53_srab_probe(struct platform_device *pdev)
380 {
381 	struct b53_platform_data *pdata = pdev->dev.platform_data;
382 	struct device_node *dn = pdev->dev.of_node;
383 	const struct of_device_id *of_id = NULL;
384 	struct b53_srab_priv *priv;
385 	struct b53_device *dev;
386 	struct resource *r;
387 
388 	if (dn)
389 		of_id = of_match_node(b53_srab_of_match, dn);
390 
391 	if (of_id) {
392 		pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
393 		if (!pdata)
394 			return -ENOMEM;
395 
396 		pdata->chip_id = (u32)(unsigned long)of_id->data;
397 	}
398 
399 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
400 	if (!priv)
401 		return -ENOMEM;
402 
403 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
404 	priv->regs = devm_ioremap_resource(&pdev->dev, r);
405 	if (IS_ERR(priv->regs))
406 		return -ENOMEM;
407 
408 	dev = b53_switch_alloc(&pdev->dev, &b53_srab_ops, priv);
409 	if (!dev)
410 		return -ENOMEM;
411 
412 	if (pdata)
413 		dev->pdata = pdata;
414 
415 	platform_set_drvdata(pdev, dev);
416 
417 	return b53_switch_register(dev);
418 }
419 
420 static int b53_srab_remove(struct platform_device *pdev)
421 {
422 	struct b53_device *dev = platform_get_drvdata(pdev);
423 
424 	if (dev)
425 		b53_switch_remove(dev);
426 
427 	return 0;
428 }
429 
430 static struct platform_driver b53_srab_driver = {
431 	.probe = b53_srab_probe,
432 	.remove = b53_srab_remove,
433 	.driver = {
434 		.name = "b53-srab-switch",
435 		.of_match_table = b53_srab_of_match,
436 	},
437 };
438 
439 module_platform_driver(b53_srab_driver);
440 MODULE_AUTHOR("Hauke Mehrtens <hauke@hauke-m.de>");
441 MODULE_DESCRIPTION("B53 Switch Register Access Bridge Registers (SRAB) access driver");
442 MODULE_LICENSE("Dual BSD/GPL");
443