1/*
2 * phy-ti-pipe3 - PIPE3 PHY driver.
3 *
4 * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * Author: Kishon Vijay Abraham I <kishon@ti.com>
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 *
17 */
18
19#include <linux/module.h>
20#include <linux/platform_device.h>
21#include <linux/slab.h>
22#include <linux/phy/phy.h>
23#include <linux/of.h>
24#include <linux/clk.h>
25#include <linux/err.h>
26#include <linux/io.h>
27#include <linux/pm_runtime.h>
28#include <linux/delay.h>
29#include <linux/phy/omap_control_phy.h>
30#include <linux/of_platform.h>
31#include <linux/spinlock.h>
32
33#define	PLL_STATUS		0x00000004
34#define	PLL_GO			0x00000008
35#define	PLL_CONFIGURATION1	0x0000000C
36#define	PLL_CONFIGURATION2	0x00000010
37#define	PLL_CONFIGURATION3	0x00000014
38#define	PLL_CONFIGURATION4	0x00000020
39
40#define	PLL_REGM_MASK		0x001FFE00
41#define	PLL_REGM_SHIFT		0x9
42#define	PLL_REGM_F_MASK		0x0003FFFF
43#define	PLL_REGM_F_SHIFT	0x0
44#define	PLL_REGN_MASK		0x000001FE
45#define	PLL_REGN_SHIFT		0x1
46#define	PLL_SELFREQDCO_MASK	0x0000000E
47#define	PLL_SELFREQDCO_SHIFT	0x1
48#define	PLL_SD_MASK		0x0003FC00
49#define	PLL_SD_SHIFT		10
50#define	SET_PLL_GO		0x1
51#define PLL_LDOPWDN		BIT(15)
52#define PLL_TICOPWDN		BIT(16)
53#define	PLL_LOCK		0x2
54#define	PLL_IDLE		0x1
55
56/*
57 * This is an Empirical value that works, need to confirm the actual
58 * value required for the PIPE3PHY_PLL_CONFIGURATION2.PLL_IDLE status
59 * to be correctly reflected in the PIPE3PHY_PLL_STATUS register.
60 */
61#define PLL_IDLE_TIME	100	/* in milliseconds */
62#define PLL_LOCK_TIME	100	/* in milliseconds */
63
64struct pipe3_dpll_params {
65	u16	m;
66	u8	n;
67	u8	freq:3;
68	u8	sd;
69	u32	mf;
70};
71
72struct pipe3_dpll_map {
73	unsigned long rate;
74	struct pipe3_dpll_params params;
75};
76
77struct ti_pipe3 {
78	void __iomem		*pll_ctrl_base;
79	struct device		*dev;
80	struct device		*control_dev;
81	struct clk		*wkupclk;
82	struct clk		*sys_clk;
83	struct clk		*refclk;
84	struct clk		*div_clk;
85	struct pipe3_dpll_map	*dpll_map;
86	bool			enabled;
87	spinlock_t		lock;	/* serialize clock enable/disable */
88	/* the below flag is needed specifically for SATA */
89	bool			refclk_enabled;
90};
91
92static struct pipe3_dpll_map dpll_map_usb[] = {
93	{12000000, {1250, 5, 4, 20, 0} },	/* 12 MHz */
94	{16800000, {3125, 20, 4, 20, 0} },	/* 16.8 MHz */
95	{19200000, {1172, 8, 4, 20, 65537} },	/* 19.2 MHz */
96	{20000000, {1000, 7, 4, 10, 0} },	/* 20 MHz */
97	{26000000, {1250, 12, 4, 20, 0} },	/* 26 MHz */
98	{38400000, {3125, 47, 4, 20, 92843} },	/* 38.4 MHz */
99	{ },					/* Terminator */
100};
101
102static struct pipe3_dpll_map dpll_map_sata[] = {
103	{12000000, {1000, 7, 4, 6, 0} },	/* 12 MHz */
104	{16800000, {714, 7, 4, 6, 0} },		/* 16.8 MHz */
105	{19200000, {625, 7, 4, 6, 0} },		/* 19.2 MHz */
106	{20000000, {600, 7, 4, 6, 0} },		/* 20 MHz */
107	{26000000, {461, 7, 4, 6, 0} },		/* 26 MHz */
108	{38400000, {312, 7, 4, 6, 0} },		/* 38.4 MHz */
109	{ },					/* Terminator */
110};
111
112static inline u32 ti_pipe3_readl(void __iomem *addr, unsigned offset)
113{
114	return __raw_readl(addr + offset);
115}
116
117static inline void ti_pipe3_writel(void __iomem *addr, unsigned offset,
118	u32 data)
119{
120	__raw_writel(data, addr + offset);
121}
122
123static struct pipe3_dpll_params *ti_pipe3_get_dpll_params(struct ti_pipe3 *phy)
124{
125	unsigned long rate;
126	struct pipe3_dpll_map *dpll_map = phy->dpll_map;
127
128	rate = clk_get_rate(phy->sys_clk);
129
130	for (; dpll_map->rate; dpll_map++) {
131		if (rate == dpll_map->rate)
132			return &dpll_map->params;
133	}
134
135	dev_err(phy->dev, "No DPLL configuration for %lu Hz SYS CLK\n", rate);
136
137	return NULL;
138}
139
140static int ti_pipe3_power_off(struct phy *x)
141{
142	struct ti_pipe3 *phy = phy_get_drvdata(x);
143
144	omap_control_phy_power(phy->control_dev, 0);
145
146	return 0;
147}
148
149static int ti_pipe3_power_on(struct phy *x)
150{
151	struct ti_pipe3 *phy = phy_get_drvdata(x);
152
153	omap_control_phy_power(phy->control_dev, 1);
154
155	return 0;
156}
157
158static int ti_pipe3_dpll_wait_lock(struct ti_pipe3 *phy)
159{
160	u32		val;
161	unsigned long	timeout;
162
163	timeout = jiffies + msecs_to_jiffies(PLL_LOCK_TIME);
164	do {
165		cpu_relax();
166		val = ti_pipe3_readl(phy->pll_ctrl_base, PLL_STATUS);
167		if (val & PLL_LOCK)
168			return 0;
169	} while (!time_after(jiffies, timeout));
170
171	dev_err(phy->dev, "DPLL failed to lock\n");
172	return -EBUSY;
173}
174
175static int ti_pipe3_dpll_program(struct ti_pipe3 *phy)
176{
177	u32			val;
178	struct pipe3_dpll_params *dpll_params;
179
180	dpll_params = ti_pipe3_get_dpll_params(phy);
181	if (!dpll_params)
182		return -EINVAL;
183
184	val = ti_pipe3_readl(phy->pll_ctrl_base, PLL_CONFIGURATION1);
185	val &= ~PLL_REGN_MASK;
186	val |= dpll_params->n << PLL_REGN_SHIFT;
187	ti_pipe3_writel(phy->pll_ctrl_base, PLL_CONFIGURATION1, val);
188
189	val = ti_pipe3_readl(phy->pll_ctrl_base, PLL_CONFIGURATION2);
190	val &= ~PLL_SELFREQDCO_MASK;
191	val |= dpll_params->freq << PLL_SELFREQDCO_SHIFT;
192	ti_pipe3_writel(phy->pll_ctrl_base, PLL_CONFIGURATION2, val);
193
194	val = ti_pipe3_readl(phy->pll_ctrl_base, PLL_CONFIGURATION1);
195	val &= ~PLL_REGM_MASK;
196	val |= dpll_params->m << PLL_REGM_SHIFT;
197	ti_pipe3_writel(phy->pll_ctrl_base, PLL_CONFIGURATION1, val);
198
199	val = ti_pipe3_readl(phy->pll_ctrl_base, PLL_CONFIGURATION4);
200	val &= ~PLL_REGM_F_MASK;
201	val |= dpll_params->mf << PLL_REGM_F_SHIFT;
202	ti_pipe3_writel(phy->pll_ctrl_base, PLL_CONFIGURATION4, val);
203
204	val = ti_pipe3_readl(phy->pll_ctrl_base, PLL_CONFIGURATION3);
205	val &= ~PLL_SD_MASK;
206	val |= dpll_params->sd << PLL_SD_SHIFT;
207	ti_pipe3_writel(phy->pll_ctrl_base, PLL_CONFIGURATION3, val);
208
209	ti_pipe3_writel(phy->pll_ctrl_base, PLL_GO, SET_PLL_GO);
210
211	return ti_pipe3_dpll_wait_lock(phy);
212}
213
214static int ti_pipe3_init(struct phy *x)
215{
216	struct ti_pipe3 *phy = phy_get_drvdata(x);
217	u32 val;
218	int ret = 0;
219
220	/*
221	 * Set pcie_pcs register to 0x96 for proper functioning of phy
222	 * as recommended in AM572x TRM SPRUHZ6, section 18.5.2.2, table
223	 * 18-1804.
224	 */
225	if (of_device_is_compatible(phy->dev->of_node, "ti,phy-pipe3-pcie")) {
226		omap_control_pcie_pcs(phy->control_dev, 0x96);
227		return 0;
228	}
229
230	/* Bring it out of IDLE if it is IDLE */
231	val = ti_pipe3_readl(phy->pll_ctrl_base, PLL_CONFIGURATION2);
232	if (val & PLL_IDLE) {
233		val &= ~PLL_IDLE;
234		ti_pipe3_writel(phy->pll_ctrl_base, PLL_CONFIGURATION2, val);
235		ret = ti_pipe3_dpll_wait_lock(phy);
236	}
237
238	/* Program the DPLL only if not locked */
239	val = ti_pipe3_readl(phy->pll_ctrl_base, PLL_STATUS);
240	if (!(val & PLL_LOCK))
241		if (ti_pipe3_dpll_program(phy))
242			return -EINVAL;
243
244	return ret;
245}
246
247static int ti_pipe3_exit(struct phy *x)
248{
249	struct ti_pipe3 *phy = phy_get_drvdata(x);
250	u32 val;
251	unsigned long timeout;
252
253	/* SATA DPLL can't be powered down due to Errata i783 and PCIe
254	 * does not have internal DPLL
255	 */
256	if (of_device_is_compatible(phy->dev->of_node, "ti,phy-pipe3-sata") ||
257	    of_device_is_compatible(phy->dev->of_node, "ti,phy-pipe3-pcie"))
258		return 0;
259
260	/* Put DPLL in IDLE mode */
261	val = ti_pipe3_readl(phy->pll_ctrl_base, PLL_CONFIGURATION2);
262	val |= PLL_IDLE;
263	ti_pipe3_writel(phy->pll_ctrl_base, PLL_CONFIGURATION2, val);
264
265	/* wait for LDO and Oscillator to power down */
266	timeout = jiffies + msecs_to_jiffies(PLL_IDLE_TIME);
267	do {
268		cpu_relax();
269		val = ti_pipe3_readl(phy->pll_ctrl_base, PLL_STATUS);
270		if ((val & PLL_TICOPWDN) && (val & PLL_LDOPWDN))
271			break;
272	} while (!time_after(jiffies, timeout));
273
274	if (!(val & PLL_TICOPWDN) || !(val & PLL_LDOPWDN)) {
275		dev_err(phy->dev, "Failed to power down: PLL_STATUS 0x%x\n",
276			val);
277		return -EBUSY;
278	}
279
280	return 0;
281}
282static struct phy_ops ops = {
283	.init		= ti_pipe3_init,
284	.exit		= ti_pipe3_exit,
285	.power_on	= ti_pipe3_power_on,
286	.power_off	= ti_pipe3_power_off,
287	.owner		= THIS_MODULE,
288};
289
290static const struct of_device_id ti_pipe3_id_table[];
291
292static int ti_pipe3_probe(struct platform_device *pdev)
293{
294	struct ti_pipe3 *phy;
295	struct phy *generic_phy;
296	struct phy_provider *phy_provider;
297	struct resource *res;
298	struct device_node *node = pdev->dev.of_node;
299	struct device_node *control_node;
300	struct platform_device *control_pdev;
301	const struct of_device_id *match;
302	struct clk *clk;
303
304	phy = devm_kzalloc(&pdev->dev, sizeof(*phy), GFP_KERNEL);
305	if (!phy)
306		return -ENOMEM;
307
308	phy->dev		= &pdev->dev;
309	spin_lock_init(&phy->lock);
310
311	if (!of_device_is_compatible(node, "ti,phy-pipe3-pcie")) {
312		match = of_match_device(ti_pipe3_id_table, &pdev->dev);
313		if (!match)
314			return -EINVAL;
315
316		phy->dpll_map = (struct pipe3_dpll_map *)match->data;
317		if (!phy->dpll_map) {
318			dev_err(&pdev->dev, "no DPLL data\n");
319			return -EINVAL;
320		}
321
322		res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
323						   "pll_ctrl");
324		phy->pll_ctrl_base = devm_ioremap_resource(&pdev->dev, res);
325		if (IS_ERR(phy->pll_ctrl_base))
326			return PTR_ERR(phy->pll_ctrl_base);
327
328		phy->sys_clk = devm_clk_get(phy->dev, "sysclk");
329		if (IS_ERR(phy->sys_clk)) {
330			dev_err(&pdev->dev, "unable to get sysclk\n");
331			return -EINVAL;
332		}
333	}
334
335	phy->refclk = devm_clk_get(phy->dev, "refclk");
336	if (IS_ERR(phy->refclk)) {
337		dev_err(&pdev->dev, "unable to get refclk\n");
338		/* older DTBs have missing refclk in SATA PHY
339		 * so don't bail out in case of SATA PHY.
340		 */
341		if (!of_device_is_compatible(node, "ti,phy-pipe3-sata"))
342			return PTR_ERR(phy->refclk);
343	}
344
345	if (!of_device_is_compatible(node, "ti,phy-pipe3-sata")) {
346		phy->wkupclk = devm_clk_get(phy->dev, "wkupclk");
347		if (IS_ERR(phy->wkupclk)) {
348			dev_err(&pdev->dev, "unable to get wkupclk\n");
349			return PTR_ERR(phy->wkupclk);
350		}
351	} else {
352		phy->wkupclk = ERR_PTR(-ENODEV);
353	}
354
355	if (of_device_is_compatible(node, "ti,phy-pipe3-pcie")) {
356
357		clk = devm_clk_get(phy->dev, "dpll_ref");
358		if (IS_ERR(clk)) {
359			dev_err(&pdev->dev, "unable to get dpll ref clk\n");
360			return PTR_ERR(clk);
361		}
362		clk_set_rate(clk, 1500000000);
363
364		clk = devm_clk_get(phy->dev, "dpll_ref_m2");
365		if (IS_ERR(clk)) {
366			dev_err(&pdev->dev, "unable to get dpll ref m2 clk\n");
367			return PTR_ERR(clk);
368		}
369		clk_set_rate(clk, 100000000);
370
371		clk = devm_clk_get(phy->dev, "phy-div");
372		if (IS_ERR(clk)) {
373			dev_err(&pdev->dev, "unable to get phy-div clk\n");
374			return PTR_ERR(clk);
375		}
376		clk_set_rate(clk, 100000000);
377
378		phy->div_clk = devm_clk_get(phy->dev, "div-clk");
379		if (IS_ERR(phy->div_clk)) {
380			dev_err(&pdev->dev, "unable to get div-clk\n");
381			return PTR_ERR(phy->div_clk);
382		}
383	} else {
384		phy->div_clk = ERR_PTR(-ENODEV);
385	}
386
387	control_node = of_parse_phandle(node, "ctrl-module", 0);
388	if (!control_node) {
389		dev_err(&pdev->dev, "Failed to get control device phandle\n");
390		return -EINVAL;
391	}
392
393	control_pdev = of_find_device_by_node(control_node);
394	if (!control_pdev) {
395		dev_err(&pdev->dev, "Failed to get control device\n");
396		return -EINVAL;
397	}
398
399	phy->control_dev = &control_pdev->dev;
400
401	omap_control_phy_power(phy->control_dev, 0);
402
403	platform_set_drvdata(pdev, phy);
404	pm_runtime_enable(phy->dev);
405
406	generic_phy = devm_phy_create(phy->dev, NULL, &ops);
407	if (IS_ERR(generic_phy))
408		return PTR_ERR(generic_phy);
409
410	phy_set_drvdata(generic_phy, phy);
411	phy_provider = devm_of_phy_provider_register(phy->dev,
412			of_phy_simple_xlate);
413	if (IS_ERR(phy_provider))
414		return PTR_ERR(phy_provider);
415
416	pm_runtime_get(&pdev->dev);
417
418	return 0;
419}
420
421static int ti_pipe3_remove(struct platform_device *pdev)
422{
423	if (!pm_runtime_suspended(&pdev->dev))
424		pm_runtime_put(&pdev->dev);
425	pm_runtime_disable(&pdev->dev);
426
427	return 0;
428}
429
430#ifdef CONFIG_PM
431static int ti_pipe3_enable_refclk(struct ti_pipe3 *phy)
432{
433	if (!IS_ERR(phy->refclk) && !phy->refclk_enabled) {
434		int ret;
435
436		ret = clk_prepare_enable(phy->refclk);
437		if (ret) {
438			dev_err(phy->dev, "Failed to enable refclk %d\n", ret);
439			return ret;
440		}
441		phy->refclk_enabled = true;
442	}
443
444	return 0;
445}
446
447static void ti_pipe3_disable_refclk(struct ti_pipe3 *phy)
448{
449	if (!IS_ERR(phy->refclk))
450		clk_disable_unprepare(phy->refclk);
451
452	phy->refclk_enabled = false;
453}
454
455static int ti_pipe3_enable_clocks(struct ti_pipe3 *phy)
456{
457	int ret = 0;
458	unsigned long flags;
459
460	spin_lock_irqsave(&phy->lock, flags);
461	if (phy->enabled)
462		goto err1;
463
464	ret = ti_pipe3_enable_refclk(phy);
465	if (ret)
466		goto err1;
467
468	if (!IS_ERR(phy->wkupclk)) {
469		ret = clk_prepare_enable(phy->wkupclk);
470		if (ret) {
471			dev_err(phy->dev, "Failed to enable wkupclk %d\n", ret);
472			goto err2;
473		}
474	}
475
476	if (!IS_ERR(phy->div_clk)) {
477		ret = clk_prepare_enable(phy->div_clk);
478		if (ret) {
479			dev_err(phy->dev, "Failed to enable div_clk %d\n", ret);
480			goto err3;
481		}
482	}
483
484	phy->enabled = true;
485	spin_unlock_irqrestore(&phy->lock, flags);
486	return 0;
487
488err3:
489	if (!IS_ERR(phy->wkupclk))
490		clk_disable_unprepare(phy->wkupclk);
491
492err2:
493	if (!IS_ERR(phy->refclk))
494		clk_disable_unprepare(phy->refclk);
495
496	ti_pipe3_disable_refclk(phy);
497err1:
498	spin_unlock_irqrestore(&phy->lock, flags);
499	return ret;
500}
501
502static void ti_pipe3_disable_clocks(struct ti_pipe3 *phy)
503{
504	unsigned long flags;
505
506	spin_lock_irqsave(&phy->lock, flags);
507	if (!phy->enabled) {
508		spin_unlock_irqrestore(&phy->lock, flags);
509		return;
510	}
511
512	if (!IS_ERR(phy->wkupclk))
513		clk_disable_unprepare(phy->wkupclk);
514	/* Don't disable refclk for SATA PHY due to Errata i783 */
515	if (!of_device_is_compatible(phy->dev->of_node, "ti,phy-pipe3-sata"))
516		ti_pipe3_disable_refclk(phy);
517	if (!IS_ERR(phy->div_clk))
518		clk_disable_unprepare(phy->div_clk);
519	phy->enabled = false;
520	spin_unlock_irqrestore(&phy->lock, flags);
521}
522
523static int ti_pipe3_runtime_suspend(struct device *dev)
524{
525	struct ti_pipe3	*phy = dev_get_drvdata(dev);
526
527	ti_pipe3_disable_clocks(phy);
528	return 0;
529}
530
531static int ti_pipe3_runtime_resume(struct device *dev)
532{
533	struct ti_pipe3	*phy = dev_get_drvdata(dev);
534	int ret = 0;
535
536	ret = ti_pipe3_enable_clocks(phy);
537	return ret;
538}
539
540static int ti_pipe3_suspend(struct device *dev)
541{
542	struct ti_pipe3	*phy = dev_get_drvdata(dev);
543
544	ti_pipe3_disable_clocks(phy);
545	return 0;
546}
547
548static int ti_pipe3_resume(struct device *dev)
549{
550	struct ti_pipe3	*phy = dev_get_drvdata(dev);
551	int ret;
552
553	ret = ti_pipe3_enable_clocks(phy);
554	if (ret)
555		return ret;
556
557	pm_runtime_disable(dev);
558	pm_runtime_set_active(dev);
559	pm_runtime_enable(dev);
560	return 0;
561}
562#endif
563
564static const struct dev_pm_ops ti_pipe3_pm_ops = {
565	SET_RUNTIME_PM_OPS(ti_pipe3_runtime_suspend,
566			   ti_pipe3_runtime_resume, NULL)
567	SET_SYSTEM_SLEEP_PM_OPS(ti_pipe3_suspend, ti_pipe3_resume)
568};
569
570static const struct of_device_id ti_pipe3_id_table[] = {
571	{
572		.compatible = "ti,phy-usb3",
573		.data = dpll_map_usb,
574	},
575	{
576		.compatible = "ti,omap-usb3",
577		.data = dpll_map_usb,
578	},
579	{
580		.compatible = "ti,phy-pipe3-sata",
581		.data = dpll_map_sata,
582	},
583	{
584		.compatible = "ti,phy-pipe3-pcie",
585	},
586	{}
587};
588MODULE_DEVICE_TABLE(of, ti_pipe3_id_table);
589
590static struct platform_driver ti_pipe3_driver = {
591	.probe		= ti_pipe3_probe,
592	.remove		= ti_pipe3_remove,
593	.driver		= {
594		.name	= "ti-pipe3",
595		.pm	= &ti_pipe3_pm_ops,
596		.of_match_table = ti_pipe3_id_table,
597	},
598};
599
600module_platform_driver(ti_pipe3_driver);
601
602MODULE_ALIAS("platform:ti_pipe3");
603MODULE_AUTHOR("Texas Instruments Inc.");
604MODULE_DESCRIPTION("TI PIPE3 phy driver");
605MODULE_LICENSE("GPL v2");
606