xref: /openbmc/linux/drivers/net/dsa/b53/b53_srab.c (revision b38269ec)
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/interrupt.h>
23 #include <linux/platform_device.h>
24 #include <linux/platform_data/b53.h>
25 #include <linux/of.h>
26 
27 #include "b53_priv.h"
28 #include "b53_serdes.h"
29 
30 /* command and status register of the SRAB */
31 #define B53_SRAB_CMDSTAT		0x2c
32 #define  B53_SRAB_CMDSTAT_RST		BIT(2)
33 #define  B53_SRAB_CMDSTAT_WRITE		BIT(1)
34 #define  B53_SRAB_CMDSTAT_GORDYN	BIT(0)
35 #define  B53_SRAB_CMDSTAT_PAGE		24
36 #define  B53_SRAB_CMDSTAT_REG		16
37 
38 /* high order word of write data to switch registe */
39 #define B53_SRAB_WD_H			0x30
40 
41 /* low order word of write data to switch registe */
42 #define B53_SRAB_WD_L			0x34
43 
44 /* high order word of read data from switch register */
45 #define B53_SRAB_RD_H			0x38
46 
47 /* low order word of read data from switch register */
48 #define B53_SRAB_RD_L			0x3c
49 
50 /* command and status register of the SRAB */
51 #define B53_SRAB_CTRLS			0x40
52 #define  B53_SRAB_CTRLS_HOST_INTR	BIT(1)
53 #define  B53_SRAB_CTRLS_RCAREQ		BIT(3)
54 #define  B53_SRAB_CTRLS_RCAGNT		BIT(4)
55 #define  B53_SRAB_CTRLS_SW_INIT_DONE	BIT(6)
56 
57 /* the register captures interrupt pulses from the switch */
58 #define B53_SRAB_INTR			0x44
59 #define  B53_SRAB_INTR_P(x)		BIT(x)
60 #define  B53_SRAB_SWITCH_PHY		BIT(8)
61 #define  B53_SRAB_1588_SYNC		BIT(9)
62 #define  B53_SRAB_IMP1_SLEEP_TIMER	BIT(10)
63 #define  B53_SRAB_P7_SLEEP_TIMER	BIT(11)
64 #define  B53_SRAB_IMP0_SLEEP_TIMER	BIT(12)
65 
66 /* Port mux configuration registers */
67 #define B53_MUX_CONFIG_P5		0x00
68 #define  MUX_CONFIG_SGMII		0
69 #define  MUX_CONFIG_MII_LITE		1
70 #define  MUX_CONFIG_RGMII		2
71 #define  MUX_CONFIG_GMII		3
72 #define  MUX_CONFIG_GPHY		4
73 #define  MUX_CONFIG_INTERNAL		5
74 #define  MUX_CONFIG_MASK		0x7
75 #define B53_MUX_CONFIG_P4		0x04
76 
77 struct b53_srab_port_priv {
78 	int irq;
79 	bool irq_enabled;
80 	struct b53_device *dev;
81 	unsigned int num;
82 	phy_interface_t mode;
83 };
84 
85 struct b53_srab_priv {
86 	void __iomem *regs;
87 	void __iomem *mux_config;
88 	struct b53_srab_port_priv port_intrs[B53_N_PORTS];
89 };
90 
91 static int b53_srab_request_grant(struct b53_device *dev)
92 {
93 	struct b53_srab_priv *priv = dev->priv;
94 	u8 __iomem *regs = priv->regs;
95 	u32 ctrls;
96 	int i;
97 
98 	ctrls = readl(regs + B53_SRAB_CTRLS);
99 	ctrls |= B53_SRAB_CTRLS_RCAREQ;
100 	writel(ctrls, regs + B53_SRAB_CTRLS);
101 
102 	for (i = 0; i < 20; i++) {
103 		ctrls = readl(regs + B53_SRAB_CTRLS);
104 		if (ctrls & B53_SRAB_CTRLS_RCAGNT)
105 			break;
106 		usleep_range(10, 100);
107 	}
108 	if (WARN_ON(i == 5))
109 		return -EIO;
110 
111 	return 0;
112 }
113 
114 static void b53_srab_release_grant(struct b53_device *dev)
115 {
116 	struct b53_srab_priv *priv = dev->priv;
117 	u8 __iomem *regs = priv->regs;
118 	u32 ctrls;
119 
120 	ctrls = readl(regs + B53_SRAB_CTRLS);
121 	ctrls &= ~B53_SRAB_CTRLS_RCAREQ;
122 	writel(ctrls, regs + B53_SRAB_CTRLS);
123 }
124 
125 static int b53_srab_op(struct b53_device *dev, u8 page, u8 reg, u32 op)
126 {
127 	struct b53_srab_priv *priv = dev->priv;
128 	u8 __iomem *regs = priv->regs;
129 	int i;
130 	u32 cmdstat;
131 
132 	/* set register address */
133 	cmdstat = (page << B53_SRAB_CMDSTAT_PAGE) |
134 		  (reg << B53_SRAB_CMDSTAT_REG) |
135 		  B53_SRAB_CMDSTAT_GORDYN |
136 		  op;
137 	writel(cmdstat, regs + B53_SRAB_CMDSTAT);
138 
139 	/* check if operation completed */
140 	for (i = 0; i < 5; ++i) {
141 		cmdstat = readl(regs + B53_SRAB_CMDSTAT);
142 		if (!(cmdstat & B53_SRAB_CMDSTAT_GORDYN))
143 			break;
144 		usleep_range(10, 100);
145 	}
146 
147 	if (WARN_ON(i == 5))
148 		return -EIO;
149 
150 	return 0;
151 }
152 
153 static int b53_srab_read8(struct b53_device *dev, u8 page, u8 reg, u8 *val)
154 {
155 	struct b53_srab_priv *priv = dev->priv;
156 	u8 __iomem *regs = priv->regs;
157 	int ret = 0;
158 
159 	ret = b53_srab_request_grant(dev);
160 	if (ret)
161 		goto err;
162 
163 	ret = b53_srab_op(dev, page, reg, 0);
164 	if (ret)
165 		goto err;
166 
167 	*val = readl(regs + B53_SRAB_RD_L) & 0xff;
168 
169 err:
170 	b53_srab_release_grant(dev);
171 
172 	return ret;
173 }
174 
175 static int b53_srab_read16(struct b53_device *dev, u8 page, u8 reg, u16 *val)
176 {
177 	struct b53_srab_priv *priv = dev->priv;
178 	u8 __iomem *regs = priv->regs;
179 	int ret = 0;
180 
181 	ret = b53_srab_request_grant(dev);
182 	if (ret)
183 		goto err;
184 
185 	ret = b53_srab_op(dev, page, reg, 0);
186 	if (ret)
187 		goto err;
188 
189 	*val = readl(regs + B53_SRAB_RD_L) & 0xffff;
190 
191 err:
192 	b53_srab_release_grant(dev);
193 
194 	return ret;
195 }
196 
197 static int b53_srab_read32(struct b53_device *dev, u8 page, u8 reg, u32 *val)
198 {
199 	struct b53_srab_priv *priv = dev->priv;
200 	u8 __iomem *regs = priv->regs;
201 	int ret = 0;
202 
203 	ret = b53_srab_request_grant(dev);
204 	if (ret)
205 		goto err;
206 
207 	ret = b53_srab_op(dev, page, reg, 0);
208 	if (ret)
209 		goto err;
210 
211 	*val = readl(regs + B53_SRAB_RD_L);
212 
213 err:
214 	b53_srab_release_grant(dev);
215 
216 	return ret;
217 }
218 
219 static int b53_srab_read48(struct b53_device *dev, u8 page, u8 reg, u64 *val)
220 {
221 	struct b53_srab_priv *priv = dev->priv;
222 	u8 __iomem *regs = priv->regs;
223 	int ret = 0;
224 
225 	ret = b53_srab_request_grant(dev);
226 	if (ret)
227 		goto err;
228 
229 	ret = b53_srab_op(dev, page, reg, 0);
230 	if (ret)
231 		goto err;
232 
233 	*val = readl(regs + B53_SRAB_RD_L);
234 	*val += ((u64)readl(regs + B53_SRAB_RD_H) & 0xffff) << 32;
235 
236 err:
237 	b53_srab_release_grant(dev);
238 
239 	return ret;
240 }
241 
242 static int b53_srab_read64(struct b53_device *dev, u8 page, u8 reg, u64 *val)
243 {
244 	struct b53_srab_priv *priv = dev->priv;
245 	u8 __iomem *regs = priv->regs;
246 	int ret = 0;
247 
248 	ret = b53_srab_request_grant(dev);
249 	if (ret)
250 		goto err;
251 
252 	ret = b53_srab_op(dev, page, reg, 0);
253 	if (ret)
254 		goto err;
255 
256 	*val = readl(regs + B53_SRAB_RD_L);
257 	*val += (u64)readl(regs + B53_SRAB_RD_H) << 32;
258 
259 err:
260 	b53_srab_release_grant(dev);
261 
262 	return ret;
263 }
264 
265 static int b53_srab_write8(struct b53_device *dev, u8 page, u8 reg, u8 value)
266 {
267 	struct b53_srab_priv *priv = dev->priv;
268 	u8 __iomem *regs = priv->regs;
269 	int ret = 0;
270 
271 	ret = b53_srab_request_grant(dev);
272 	if (ret)
273 		goto err;
274 
275 	writel(value, regs + B53_SRAB_WD_L);
276 
277 	ret = b53_srab_op(dev, page, reg, B53_SRAB_CMDSTAT_WRITE);
278 
279 err:
280 	b53_srab_release_grant(dev);
281 
282 	return ret;
283 }
284 
285 static int b53_srab_write16(struct b53_device *dev, u8 page, u8 reg,
286 			    u16 value)
287 {
288 	struct b53_srab_priv *priv = dev->priv;
289 	u8 __iomem *regs = priv->regs;
290 	int ret = 0;
291 
292 	ret = b53_srab_request_grant(dev);
293 	if (ret)
294 		goto err;
295 
296 	writel(value, regs + B53_SRAB_WD_L);
297 
298 	ret = b53_srab_op(dev, page, reg, B53_SRAB_CMDSTAT_WRITE);
299 
300 err:
301 	b53_srab_release_grant(dev);
302 
303 	return ret;
304 }
305 
306 static int b53_srab_write32(struct b53_device *dev, u8 page, u8 reg,
307 			    u32 value)
308 {
309 	struct b53_srab_priv *priv = dev->priv;
310 	u8 __iomem *regs = priv->regs;
311 	int ret = 0;
312 
313 	ret = b53_srab_request_grant(dev);
314 	if (ret)
315 		goto err;
316 
317 	writel(value, regs + B53_SRAB_WD_L);
318 
319 	ret = b53_srab_op(dev, page, reg, B53_SRAB_CMDSTAT_WRITE);
320 
321 err:
322 	b53_srab_release_grant(dev);
323 
324 	return ret;
325 }
326 
327 static int b53_srab_write48(struct b53_device *dev, u8 page, u8 reg,
328 			    u64 value)
329 {
330 	struct b53_srab_priv *priv = dev->priv;
331 	u8 __iomem *regs = priv->regs;
332 	int ret = 0;
333 
334 	ret = b53_srab_request_grant(dev);
335 	if (ret)
336 		goto err;
337 
338 	writel((u32)value, regs + B53_SRAB_WD_L);
339 	writel((u16)(value >> 32), regs + B53_SRAB_WD_H);
340 
341 	ret = b53_srab_op(dev, page, reg, B53_SRAB_CMDSTAT_WRITE);
342 
343 err:
344 	b53_srab_release_grant(dev);
345 
346 	return ret;
347 }
348 
349 static int b53_srab_write64(struct b53_device *dev, u8 page, u8 reg,
350 			    u64 value)
351 {
352 	struct b53_srab_priv *priv = dev->priv;
353 	u8 __iomem *regs = priv->regs;
354 	int ret = 0;
355 
356 	ret = b53_srab_request_grant(dev);
357 	if (ret)
358 		goto err;
359 
360 	writel((u32)value, regs + B53_SRAB_WD_L);
361 	writel((u32)(value >> 32), regs + B53_SRAB_WD_H);
362 
363 	ret = b53_srab_op(dev, page, reg, B53_SRAB_CMDSTAT_WRITE);
364 
365 err:
366 	b53_srab_release_grant(dev);
367 
368 	return ret;
369 }
370 
371 static irqreturn_t b53_srab_port_thread(int irq, void *dev_id)
372 {
373 	struct b53_srab_port_priv *port = dev_id;
374 	struct b53_device *dev = port->dev;
375 
376 	if (port->mode == PHY_INTERFACE_MODE_SGMII)
377 		b53_port_event(dev->ds, port->num);
378 
379 	return IRQ_HANDLED;
380 }
381 
382 static irqreturn_t b53_srab_port_isr(int irq, void *dev_id)
383 {
384 	struct b53_srab_port_priv *port = dev_id;
385 	struct b53_device *dev = port->dev;
386 	struct b53_srab_priv *priv = dev->priv;
387 
388 	/* Acknowledge the interrupt */
389 	writel(BIT(port->num), priv->regs + B53_SRAB_INTR);
390 
391 	return IRQ_WAKE_THREAD;
392 }
393 
394 #if IS_ENABLED(CONFIG_B53_SERDES)
395 static u8 b53_srab_serdes_map_lane(struct b53_device *dev, int port)
396 {
397 	struct b53_srab_priv *priv = dev->priv;
398 	struct b53_srab_port_priv *p = &priv->port_intrs[port];
399 
400 	if (p->mode != PHY_INTERFACE_MODE_SGMII)
401 		return B53_INVALID_LANE;
402 
403 	switch (port) {
404 	case 5:
405 		return 0;
406 	case 4:
407 		return 1;
408 	default:
409 		return B53_INVALID_LANE;
410 	}
411 }
412 #endif
413 
414 static int b53_srab_irq_enable(struct b53_device *dev, int port)
415 {
416 	struct b53_srab_priv *priv = dev->priv;
417 	struct b53_srab_port_priv *p = &priv->port_intrs[port];
418 	int ret = 0;
419 
420 	/* Interrupt is optional and was not specified, do not make
421 	 * this fatal
422 	 */
423 	if (p->irq == -ENXIO)
424 		return ret;
425 
426 	ret = request_threaded_irq(p->irq, b53_srab_port_isr,
427 				   b53_srab_port_thread, 0,
428 				   dev_name(dev->dev), p);
429 	if (!ret)
430 		p->irq_enabled = true;
431 
432 	return ret;
433 }
434 
435 static void b53_srab_irq_disable(struct b53_device *dev, int port)
436 {
437 	struct b53_srab_priv *priv = dev->priv;
438 	struct b53_srab_port_priv *p = &priv->port_intrs[port];
439 
440 	if (p->irq_enabled) {
441 		free_irq(p->irq, p);
442 		p->irq_enabled = false;
443 	}
444 }
445 
446 static const struct b53_io_ops b53_srab_ops = {
447 	.read8 = b53_srab_read8,
448 	.read16 = b53_srab_read16,
449 	.read32 = b53_srab_read32,
450 	.read48 = b53_srab_read48,
451 	.read64 = b53_srab_read64,
452 	.write8 = b53_srab_write8,
453 	.write16 = b53_srab_write16,
454 	.write32 = b53_srab_write32,
455 	.write48 = b53_srab_write48,
456 	.write64 = b53_srab_write64,
457 	.irq_enable = b53_srab_irq_enable,
458 	.irq_disable = b53_srab_irq_disable,
459 #if IS_ENABLED(CONFIG_B53_SERDES)
460 	.serdes_map_lane = b53_srab_serdes_map_lane,
461 	.serdes_link_state = b53_serdes_link_state,
462 	.serdes_config = b53_serdes_config,
463 	.serdes_an_restart = b53_serdes_an_restart,
464 	.serdes_link_set = b53_serdes_link_set,
465 	.serdes_phylink_validate = b53_serdes_phylink_validate,
466 #endif
467 };
468 
469 static const struct of_device_id b53_srab_of_match[] = {
470 	{ .compatible = "brcm,bcm53010-srab" },
471 	{ .compatible = "brcm,bcm53011-srab" },
472 	{ .compatible = "brcm,bcm53012-srab" },
473 	{ .compatible = "brcm,bcm53018-srab" },
474 	{ .compatible = "brcm,bcm53019-srab" },
475 	{ .compatible = "brcm,bcm5301x-srab" },
476 	{ .compatible = "brcm,bcm11360-srab", .data = (void *)BCM583XX_DEVICE_ID },
477 	{ .compatible = "brcm,bcm58522-srab", .data = (void *)BCM58XX_DEVICE_ID },
478 	{ .compatible = "brcm,bcm58525-srab", .data = (void *)BCM58XX_DEVICE_ID },
479 	{ .compatible = "brcm,bcm58535-srab", .data = (void *)BCM58XX_DEVICE_ID },
480 	{ .compatible = "brcm,bcm58622-srab", .data = (void *)BCM58XX_DEVICE_ID },
481 	{ .compatible = "brcm,bcm58623-srab", .data = (void *)BCM58XX_DEVICE_ID },
482 	{ .compatible = "brcm,bcm58625-srab", .data = (void *)BCM58XX_DEVICE_ID },
483 	{ .compatible = "brcm,bcm88312-srab", .data = (void *)BCM58XX_DEVICE_ID },
484 	{ .compatible = "brcm,cygnus-srab", .data = (void *)BCM583XX_DEVICE_ID },
485 	{ .compatible = "brcm,nsp-srab", .data = (void *)BCM58XX_DEVICE_ID },
486 	{ .compatible = "brcm,omega-srab", .data = (void *)BCM583XX_DEVICE_ID },
487 	{ /* sentinel */ },
488 };
489 MODULE_DEVICE_TABLE(of, b53_srab_of_match);
490 
491 static void b53_srab_intr_set(struct b53_srab_priv *priv, bool set)
492 {
493 	u32 reg;
494 
495 	reg = readl(priv->regs + B53_SRAB_CTRLS);
496 	if (set)
497 		reg |= B53_SRAB_CTRLS_HOST_INTR;
498 	else
499 		reg &= ~B53_SRAB_CTRLS_HOST_INTR;
500 	writel(reg, priv->regs + B53_SRAB_CTRLS);
501 }
502 
503 static void b53_srab_prepare_irq(struct platform_device *pdev)
504 {
505 	struct b53_device *dev = platform_get_drvdata(pdev);
506 	struct b53_srab_priv *priv = dev->priv;
507 	struct b53_srab_port_priv *port;
508 	unsigned int i;
509 	char *name;
510 
511 	/* Clear all pending interrupts */
512 	writel(0xffffffff, priv->regs + B53_SRAB_INTR);
513 
514 	for (i = 0; i < B53_N_PORTS; i++) {
515 		port = &priv->port_intrs[i];
516 
517 		/* There is no port 6 */
518 		if (i == 6)
519 			continue;
520 
521 		name = kasprintf(GFP_KERNEL, "link_state_p%d", i);
522 		if (!name)
523 			return;
524 
525 		port->num = i;
526 		port->dev = dev;
527 		port->irq = platform_get_irq_byname_optional(pdev, name);
528 		kfree(name);
529 	}
530 
531 	b53_srab_intr_set(priv, true);
532 }
533 
534 static void b53_srab_mux_init(struct platform_device *pdev)
535 {
536 	struct b53_device *dev = platform_get_drvdata(pdev);
537 	struct b53_srab_priv *priv = dev->priv;
538 	struct b53_srab_port_priv *p;
539 	unsigned int port;
540 	u32 reg, off = 0;
541 	int ret;
542 
543 	if (dev->pdata && dev->pdata->chip_id != BCM58XX_DEVICE_ID)
544 		return;
545 
546 	priv->mux_config = devm_platform_ioremap_resource(pdev, 1);
547 	if (IS_ERR(priv->mux_config))
548 		return;
549 
550 	/* Obtain the port mux configuration so we know which lanes
551 	 * actually map to SerDes lanes
552 	 */
553 	for (port = 5; port > 3; port--, off += 4) {
554 		p = &priv->port_intrs[port];
555 
556 		reg = readl(priv->mux_config + B53_MUX_CONFIG_P5 + off);
557 		switch (reg & MUX_CONFIG_MASK) {
558 		case MUX_CONFIG_SGMII:
559 			p->mode = PHY_INTERFACE_MODE_SGMII;
560 			ret = b53_serdes_init(dev, port);
561 			if (ret)
562 				continue;
563 			break;
564 		case MUX_CONFIG_MII_LITE:
565 			p->mode = PHY_INTERFACE_MODE_MII;
566 			break;
567 		case MUX_CONFIG_GMII:
568 			p->mode = PHY_INTERFACE_MODE_GMII;
569 			break;
570 		case MUX_CONFIG_RGMII:
571 			p->mode = PHY_INTERFACE_MODE_RGMII;
572 			break;
573 		case MUX_CONFIG_INTERNAL:
574 			p->mode = PHY_INTERFACE_MODE_INTERNAL;
575 			break;
576 		default:
577 			p->mode = PHY_INTERFACE_MODE_NA;
578 			break;
579 		}
580 
581 		if (p->mode != PHY_INTERFACE_MODE_NA)
582 			dev_info(&pdev->dev, "Port %d mode: %s\n",
583 				 port, phy_modes(p->mode));
584 	}
585 }
586 
587 static int b53_srab_probe(struct platform_device *pdev)
588 {
589 	struct b53_platform_data *pdata = pdev->dev.platform_data;
590 	struct device_node *dn = pdev->dev.of_node;
591 	const struct of_device_id *of_id = NULL;
592 	struct b53_srab_priv *priv;
593 	struct b53_device *dev;
594 
595 	if (dn)
596 		of_id = of_match_node(b53_srab_of_match, dn);
597 
598 	if (of_id) {
599 		pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
600 		if (!pdata)
601 			return -ENOMEM;
602 
603 		pdata->chip_id = (u32)(unsigned long)of_id->data;
604 	}
605 
606 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
607 	if (!priv)
608 		return -ENOMEM;
609 
610 	priv->regs = devm_platform_ioremap_resource(pdev, 0);
611 	if (IS_ERR(priv->regs))
612 		return PTR_ERR(priv->regs);
613 
614 	dev = b53_switch_alloc(&pdev->dev, &b53_srab_ops, priv);
615 	if (!dev)
616 		return -ENOMEM;
617 
618 	if (pdata)
619 		dev->pdata = pdata;
620 
621 	platform_set_drvdata(pdev, dev);
622 
623 	b53_srab_prepare_irq(pdev);
624 	b53_srab_mux_init(pdev);
625 
626 	return b53_switch_register(dev);
627 }
628 
629 static int b53_srab_remove(struct platform_device *pdev)
630 {
631 	struct b53_device *dev = platform_get_drvdata(pdev);
632 	struct b53_srab_priv *priv = dev->priv;
633 
634 	b53_srab_intr_set(priv, false);
635 	b53_switch_remove(dev);
636 
637 	return 0;
638 }
639 
640 static struct platform_driver b53_srab_driver = {
641 	.probe = b53_srab_probe,
642 	.remove = b53_srab_remove,
643 	.driver = {
644 		.name = "b53-srab-switch",
645 		.of_match_table = b53_srab_of_match,
646 	},
647 };
648 
649 module_platform_driver(b53_srab_driver);
650 MODULE_AUTHOR("Hauke Mehrtens <hauke@hauke-m.de>");
651 MODULE_DESCRIPTION("B53 Switch Register Access Bridge Registers (SRAB) access driver");
652 MODULE_LICENSE("Dual BSD/GPL");
653