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
77struct 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
85struct 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
91static 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
114static 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
125static 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
153static 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
169err:
170	b53_srab_release_grant(dev);
171
172	return ret;
173}
174
175static 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
191err:
192	b53_srab_release_grant(dev);
193
194	return ret;
195}
196
197static 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
213err:
214	b53_srab_release_grant(dev);
215
216	return ret;
217}
218
219static 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
236err:
237	b53_srab_release_grant(dev);
238
239	return ret;
240}
241
242static 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
259err:
260	b53_srab_release_grant(dev);
261
262	return ret;
263}
264
265static 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
279err:
280	b53_srab_release_grant(dev);
281
282	return ret;
283}
284
285static 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
300err:
301	b53_srab_release_grant(dev);
302
303	return ret;
304}
305
306static 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
321err:
322	b53_srab_release_grant(dev);
323
324	return ret;
325}
326
327static 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
343err:
344	b53_srab_release_grant(dev);
345
346	return ret;
347}
348
349static 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
365err:
366	b53_srab_release_grant(dev);
367
368	return ret;
369}
370
371static 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
382static 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)
395static 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
414static 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
435static 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
446static void b53_srab_phylink_get_caps(struct b53_device *dev, int port,
447				      struct phylink_config *config)
448{
449	struct b53_srab_priv *priv = dev->priv;
450	struct b53_srab_port_priv *p = &priv->port_intrs[port];
451
452	switch (p->mode) {
453	case PHY_INTERFACE_MODE_SGMII:
454#if IS_ENABLED(CONFIG_B53_SERDES)
455		/* If p->mode indicates SGMII mode, that essentially means we
456		 * are using a serdes. As the serdes for the capabilities.
457		 */
458		b53_serdes_phylink_get_caps(dev, port, config);
459#endif
460		break;
461
462	case PHY_INTERFACE_MODE_NA:
463		break;
464
465	case PHY_INTERFACE_MODE_RGMII:
466		/* If we support RGMII, support all RGMII modes, since
467		 * that dictates the PHY delay settings.
468		 */
469		phy_interface_set_rgmii(config->supported_interfaces);
470		break;
471
472	default:
473		/* Some other mode (e.g. MII, GMII etc) */
474		__set_bit(p->mode, config->supported_interfaces);
475		break;
476	}
477}
478
479static const struct b53_io_ops b53_srab_ops = {
480	.read8 = b53_srab_read8,
481	.read16 = b53_srab_read16,
482	.read32 = b53_srab_read32,
483	.read48 = b53_srab_read48,
484	.read64 = b53_srab_read64,
485	.write8 = b53_srab_write8,
486	.write16 = b53_srab_write16,
487	.write32 = b53_srab_write32,
488	.write48 = b53_srab_write48,
489	.write64 = b53_srab_write64,
490	.irq_enable = b53_srab_irq_enable,
491	.irq_disable = b53_srab_irq_disable,
492	.phylink_get_caps = b53_srab_phylink_get_caps,
493#if IS_ENABLED(CONFIG_B53_SERDES)
494	.phylink_mac_select_pcs = b53_serdes_phylink_mac_select_pcs,
495	.serdes_map_lane = b53_srab_serdes_map_lane,
496	.serdes_link_set = b53_serdes_link_set,
497#endif
498};
499
500static const struct of_device_id b53_srab_of_match[] = {
501	{ .compatible = "brcm,bcm53010-srab" },
502	{ .compatible = "brcm,bcm53011-srab" },
503	{ .compatible = "brcm,bcm53012-srab" },
504	{ .compatible = "brcm,bcm53018-srab" },
505	{ .compatible = "brcm,bcm53019-srab" },
506	{ .compatible = "brcm,bcm5301x-srab" },
507	{ .compatible = "brcm,bcm11360-srab", .data = (void *)BCM583XX_DEVICE_ID },
508	{ .compatible = "brcm,bcm58522-srab", .data = (void *)BCM58XX_DEVICE_ID },
509	{ .compatible = "brcm,bcm58525-srab", .data = (void *)BCM58XX_DEVICE_ID },
510	{ .compatible = "brcm,bcm58535-srab", .data = (void *)BCM58XX_DEVICE_ID },
511	{ .compatible = "brcm,bcm58622-srab", .data = (void *)BCM58XX_DEVICE_ID },
512	{ .compatible = "brcm,bcm58623-srab", .data = (void *)BCM58XX_DEVICE_ID },
513	{ .compatible = "brcm,bcm58625-srab", .data = (void *)BCM58XX_DEVICE_ID },
514	{ .compatible = "brcm,bcm88312-srab", .data = (void *)BCM58XX_DEVICE_ID },
515	{ .compatible = "brcm,cygnus-srab", .data = (void *)BCM583XX_DEVICE_ID },
516	{ .compatible = "brcm,nsp-srab", .data = (void *)BCM58XX_DEVICE_ID },
517	{ .compatible = "brcm,omega-srab", .data = (void *)BCM583XX_DEVICE_ID },
518	{ /* sentinel */ },
519};
520MODULE_DEVICE_TABLE(of, b53_srab_of_match);
521
522static void b53_srab_intr_set(struct b53_srab_priv *priv, bool set)
523{
524	u32 reg;
525
526	reg = readl(priv->regs + B53_SRAB_CTRLS);
527	if (set)
528		reg |= B53_SRAB_CTRLS_HOST_INTR;
529	else
530		reg &= ~B53_SRAB_CTRLS_HOST_INTR;
531	writel(reg, priv->regs + B53_SRAB_CTRLS);
532}
533
534static void b53_srab_prepare_irq(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 *port;
539	unsigned int i;
540	char *name;
541
542	/* Clear all pending interrupts */
543	writel(0xffffffff, priv->regs + B53_SRAB_INTR);
544
545	for (i = 0; i < B53_N_PORTS; i++) {
546		port = &priv->port_intrs[i];
547
548		/* There is no port 6 */
549		if (i == 6)
550			continue;
551
552		name = kasprintf(GFP_KERNEL, "link_state_p%d", i);
553		if (!name)
554			return;
555
556		port->num = i;
557		port->dev = dev;
558		port->irq = platform_get_irq_byname_optional(pdev, name);
559		kfree(name);
560	}
561
562	b53_srab_intr_set(priv, true);
563}
564
565static void b53_srab_mux_init(struct platform_device *pdev)
566{
567	struct b53_device *dev = platform_get_drvdata(pdev);
568	struct b53_srab_priv *priv = dev->priv;
569	struct b53_srab_port_priv *p;
570	unsigned int port;
571	u32 reg, off = 0;
572	int ret;
573
574	if (dev->pdata && dev->pdata->chip_id != BCM58XX_DEVICE_ID)
575		return;
576
577	priv->mux_config = devm_platform_ioremap_resource(pdev, 1);
578	if (IS_ERR(priv->mux_config))
579		return;
580
581	/* Obtain the port mux configuration so we know which lanes
582	 * actually map to SerDes lanes
583	 */
584	for (port = 5; port > 3; port--, off += 4) {
585		p = &priv->port_intrs[port];
586
587		reg = readl(priv->mux_config + B53_MUX_CONFIG_P5 + off);
588		switch (reg & MUX_CONFIG_MASK) {
589		case MUX_CONFIG_SGMII:
590			p->mode = PHY_INTERFACE_MODE_SGMII;
591			ret = b53_serdes_init(dev, port);
592			if (ret)
593				continue;
594			break;
595		case MUX_CONFIG_MII_LITE:
596			p->mode = PHY_INTERFACE_MODE_MII;
597			break;
598		case MUX_CONFIG_GMII:
599			p->mode = PHY_INTERFACE_MODE_GMII;
600			break;
601		case MUX_CONFIG_RGMII:
602			p->mode = PHY_INTERFACE_MODE_RGMII;
603			break;
604		case MUX_CONFIG_INTERNAL:
605			p->mode = PHY_INTERFACE_MODE_INTERNAL;
606			break;
607		default:
608			p->mode = PHY_INTERFACE_MODE_NA;
609			break;
610		}
611
612		if (p->mode != PHY_INTERFACE_MODE_NA)
613			dev_info(&pdev->dev, "Port %d mode: %s\n",
614				 port, phy_modes(p->mode));
615	}
616}
617
618static int b53_srab_probe(struct platform_device *pdev)
619{
620	struct b53_platform_data *pdata = pdev->dev.platform_data;
621	struct device_node *dn = pdev->dev.of_node;
622	const struct of_device_id *of_id = NULL;
623	struct b53_srab_priv *priv;
624	struct b53_device *dev;
625
626	if (dn)
627		of_id = of_match_node(b53_srab_of_match, dn);
628
629	if (of_id) {
630		pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
631		if (!pdata)
632			return -ENOMEM;
633
634		pdata->chip_id = (u32)(unsigned long)of_id->data;
635	}
636
637	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
638	if (!priv)
639		return -ENOMEM;
640
641	priv->regs = devm_platform_ioremap_resource(pdev, 0);
642	if (IS_ERR(priv->regs))
643		return PTR_ERR(priv->regs);
644
645	dev = b53_switch_alloc(&pdev->dev, &b53_srab_ops, priv);
646	if (!dev)
647		return -ENOMEM;
648
649	if (pdata)
650		dev->pdata = pdata;
651
652	platform_set_drvdata(pdev, dev);
653
654	b53_srab_prepare_irq(pdev);
655	b53_srab_mux_init(pdev);
656
657	return b53_switch_register(dev);
658}
659
660static void b53_srab_remove(struct platform_device *pdev)
661{
662	struct b53_device *dev = platform_get_drvdata(pdev);
663
664	if (!dev)
665		return;
666
667	b53_srab_intr_set(dev->priv, false);
668	b53_switch_remove(dev);
669}
670
671static void b53_srab_shutdown(struct platform_device *pdev)
672{
673	struct b53_device *dev = platform_get_drvdata(pdev);
674
675	if (!dev)
676		return;
677
678	b53_switch_shutdown(dev);
679
680	platform_set_drvdata(pdev, NULL);
681}
682
683static struct platform_driver b53_srab_driver = {
684	.probe = b53_srab_probe,
685	.remove_new = b53_srab_remove,
686	.shutdown = b53_srab_shutdown,
687	.driver = {
688		.name = "b53-srab-switch",
689		.of_match_table = b53_srab_of_match,
690	},
691};
692
693module_platform_driver(b53_srab_driver);
694MODULE_AUTHOR("Hauke Mehrtens <hauke@hauke-m.de>");
695MODULE_DESCRIPTION("B53 Switch Register Access Bridge Registers (SRAB) access driver");
696MODULE_LICENSE("Dual BSD/GPL");
697