1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * phy-uniphier-usb3hs.c - HS-PHY driver for Socionext UniPhier USB3 controller
4  * Copyright 2015-2018 Socionext Inc.
5  * Author:
6  *      Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
7  * Contributors:
8  *      Motoya Tanigawa <tanigawa.motoya@socionext.com>
9  *      Masami Hiramatsu <masami.hiramatsu@linaro.org>
10  */
11 
12 #include <linux/bitfield.h>
13 #include <linux/bitops.h>
14 #include <linux/clk.h>
15 #include <linux/io.h>
16 #include <linux/module.h>
17 #include <linux/nvmem-consumer.h>
18 #include <linux/of.h>
19 #include <linux/of_platform.h>
20 #include <linux/phy/phy.h>
21 #include <linux/platform_device.h>
22 #include <linux/regulator/consumer.h>
23 #include <linux/reset.h>
24 #include <linux/slab.h>
25 
26 #define HSPHY_CFG0		0x0
27 #define HSPHY_CFG0_HS_I_MASK	GENMASK(31, 28)
28 #define HSPHY_CFG0_HSDISC_MASK	GENMASK(27, 26)
29 #define HSPHY_CFG0_SWING_MASK	GENMASK(17, 16)
30 #define HSPHY_CFG0_SEL_T_MASK	GENMASK(15, 12)
31 #define HSPHY_CFG0_RTERM_MASK	GENMASK(7, 6)
32 #define HSPHY_CFG0_TRIMMASK	(HSPHY_CFG0_HS_I_MASK \
33 				 | HSPHY_CFG0_SEL_T_MASK \
34 				 | HSPHY_CFG0_RTERM_MASK)
35 
36 #define HSPHY_CFG1		0x4
37 #define HSPHY_CFG1_DAT_EN	BIT(29)
38 #define HSPHY_CFG1_ADR_EN	BIT(28)
39 #define HSPHY_CFG1_ADR_MASK	GENMASK(27, 16)
40 #define HSPHY_CFG1_DAT_MASK	GENMASK(23, 16)
41 
42 #define PHY_F(regno, msb, lsb) { (regno), (msb), (lsb) }
43 
44 #define RX_CHK_SYNC	PHY_F(0, 5, 5)	/* RX sync mode */
45 #define RX_SYNC_SEL	PHY_F(1, 1, 0)	/* RX sync length */
46 #define LS_SLEW		PHY_F(10, 6, 6)	/* LS mode slew rate */
47 #define FS_LS_DRV	PHY_F(10, 5, 5)	/* FS/LS slew rate */
48 
49 #define MAX_PHY_PARAMS	4
50 
51 struct uniphier_u3hsphy_param {
52 	struct {
53 		int reg_no;
54 		int msb;
55 		int lsb;
56 	} field;
57 	u8 value;
58 };
59 
60 struct uniphier_u3hsphy_trim_param {
61 	unsigned int rterm;
62 	unsigned int sel_t;
63 	unsigned int hs_i;
64 };
65 
66 #define trim_param_is_valid(p)	((p)->rterm || (p)->sel_t || (p)->hs_i)
67 
68 struct uniphier_u3hsphy_priv {
69 	struct device *dev;
70 	void __iomem *base;
71 	struct clk *clk, *clk_parent, *clk_ext, *clk_parent_gio;
72 	struct reset_control *rst, *rst_parent, *rst_parent_gio;
73 	struct regulator *vbus;
74 	const struct uniphier_u3hsphy_soc_data *data;
75 };
76 
77 struct uniphier_u3hsphy_soc_data {
78 	bool is_legacy;
79 	int nparams;
80 	const struct uniphier_u3hsphy_param param[MAX_PHY_PARAMS];
81 	u32 config0;
82 	u32 config1;
83 	void (*trim_func)(struct uniphier_u3hsphy_priv *priv, u32 *pconfig,
84 			  struct uniphier_u3hsphy_trim_param *pt);
85 };
86 
87 static void uniphier_u3hsphy_trim_ld20(struct uniphier_u3hsphy_priv *priv,
88 				       u32 *pconfig,
89 				       struct uniphier_u3hsphy_trim_param *pt)
90 {
91 	*pconfig &= ~HSPHY_CFG0_RTERM_MASK;
92 	*pconfig |= FIELD_PREP(HSPHY_CFG0_RTERM_MASK, pt->rterm);
93 
94 	*pconfig &= ~HSPHY_CFG0_SEL_T_MASK;
95 	*pconfig |= FIELD_PREP(HSPHY_CFG0_SEL_T_MASK, pt->sel_t);
96 
97 	*pconfig &= ~HSPHY_CFG0_HS_I_MASK;
98 	*pconfig |= FIELD_PREP(HSPHY_CFG0_HS_I_MASK,  pt->hs_i);
99 }
100 
101 static int uniphier_u3hsphy_get_nvparam(struct uniphier_u3hsphy_priv *priv,
102 					const char *name, unsigned int *val)
103 {
104 	struct nvmem_cell *cell;
105 	u8 *buf;
106 
107 	cell = devm_nvmem_cell_get(priv->dev, name);
108 	if (IS_ERR(cell))
109 		return PTR_ERR(cell);
110 
111 	buf = nvmem_cell_read(cell, NULL);
112 	if (IS_ERR(buf))
113 		return PTR_ERR(buf);
114 
115 	*val = *buf;
116 
117 	kfree(buf);
118 
119 	return 0;
120 }
121 
122 static int uniphier_u3hsphy_get_nvparams(struct uniphier_u3hsphy_priv *priv,
123 					 struct uniphier_u3hsphy_trim_param *pt)
124 {
125 	int ret;
126 
127 	ret = uniphier_u3hsphy_get_nvparam(priv, "rterm", &pt->rterm);
128 	if (ret)
129 		return ret;
130 
131 	ret = uniphier_u3hsphy_get_nvparam(priv, "sel_t", &pt->sel_t);
132 	if (ret)
133 		return ret;
134 
135 	ret = uniphier_u3hsphy_get_nvparam(priv, "hs_i", &pt->hs_i);
136 	if (ret)
137 		return ret;
138 
139 	return 0;
140 }
141 
142 static int uniphier_u3hsphy_update_config(struct uniphier_u3hsphy_priv *priv,
143 					  u32 *pconfig)
144 {
145 	struct uniphier_u3hsphy_trim_param trim;
146 	int ret, trimmed = 0;
147 
148 	if (priv->data->trim_func) {
149 		ret = uniphier_u3hsphy_get_nvparams(priv, &trim);
150 		if (ret == -EPROBE_DEFER)
151 			return ret;
152 
153 		/*
154 		 * call trim_func only when trimming parameters that aren't
155 		 * all-zero can be acquired. All-zero parameters mean nothing
156 		 * has been written to nvmem.
157 		 */
158 		if (!ret && trim_param_is_valid(&trim)) {
159 			priv->data->trim_func(priv, pconfig, &trim);
160 			trimmed = 1;
161 		} else {
162 			dev_dbg(priv->dev, "can't get parameter from nvmem\n");
163 		}
164 	}
165 
166 	/* use default parameters without trimming values */
167 	if (!trimmed) {
168 		*pconfig &= ~HSPHY_CFG0_HSDISC_MASK;
169 		*pconfig |= FIELD_PREP(HSPHY_CFG0_HSDISC_MASK, 3);
170 	}
171 
172 	return 0;
173 }
174 
175 static void uniphier_u3hsphy_set_param(struct uniphier_u3hsphy_priv *priv,
176 				       const struct uniphier_u3hsphy_param *p)
177 {
178 	u32 val;
179 	u32 field_mask = GENMASK(p->field.msb, p->field.lsb);
180 	u8 data;
181 
182 	val = readl(priv->base + HSPHY_CFG1);
183 	val &= ~HSPHY_CFG1_ADR_MASK;
184 	val |= FIELD_PREP(HSPHY_CFG1_ADR_MASK, p->field.reg_no)
185 		| HSPHY_CFG1_ADR_EN;
186 	writel(val, priv->base + HSPHY_CFG1);
187 
188 	val = readl(priv->base + HSPHY_CFG1);
189 	val &= ~HSPHY_CFG1_ADR_EN;
190 	writel(val, priv->base + HSPHY_CFG1);
191 
192 	val = readl(priv->base + HSPHY_CFG1);
193 	val &= ~FIELD_PREP(HSPHY_CFG1_DAT_MASK, field_mask);
194 	data = field_mask & (p->value << p->field.lsb);
195 	val |=  FIELD_PREP(HSPHY_CFG1_DAT_MASK, data) | HSPHY_CFG1_DAT_EN;
196 	writel(val, priv->base + HSPHY_CFG1);
197 
198 	val = readl(priv->base + HSPHY_CFG1);
199 	val &= ~HSPHY_CFG1_DAT_EN;
200 	writel(val, priv->base + HSPHY_CFG1);
201 }
202 
203 static int uniphier_u3hsphy_power_on(struct phy *phy)
204 {
205 	struct uniphier_u3hsphy_priv *priv = phy_get_drvdata(phy);
206 	int ret;
207 
208 	ret = clk_prepare_enable(priv->clk_ext);
209 	if (ret)
210 		return ret;
211 
212 	ret = clk_prepare_enable(priv->clk);
213 	if (ret)
214 		goto out_clk_ext_disable;
215 
216 	ret = reset_control_deassert(priv->rst);
217 	if (ret)
218 		goto out_clk_disable;
219 
220 	if (priv->vbus) {
221 		ret = regulator_enable(priv->vbus);
222 		if (ret)
223 			goto out_rst_assert;
224 	}
225 
226 	return 0;
227 
228 out_rst_assert:
229 	reset_control_assert(priv->rst);
230 out_clk_disable:
231 	clk_disable_unprepare(priv->clk);
232 out_clk_ext_disable:
233 	clk_disable_unprepare(priv->clk_ext);
234 
235 	return ret;
236 }
237 
238 static int uniphier_u3hsphy_power_off(struct phy *phy)
239 {
240 	struct uniphier_u3hsphy_priv *priv = phy_get_drvdata(phy);
241 
242 	if (priv->vbus)
243 		regulator_disable(priv->vbus);
244 
245 	reset_control_assert(priv->rst);
246 	clk_disable_unprepare(priv->clk);
247 	clk_disable_unprepare(priv->clk_ext);
248 
249 	return 0;
250 }
251 
252 static int uniphier_u3hsphy_init(struct phy *phy)
253 {
254 	struct uniphier_u3hsphy_priv *priv = phy_get_drvdata(phy);
255 	u32 config0, config1;
256 	int i, ret;
257 
258 	ret = clk_prepare_enable(priv->clk_parent);
259 	if (ret)
260 		return ret;
261 
262 	ret = clk_prepare_enable(priv->clk_parent_gio);
263 	if (ret)
264 		goto out_clk_disable;
265 
266 	ret = reset_control_deassert(priv->rst_parent);
267 	if (ret)
268 		goto out_clk_gio_disable;
269 
270 	ret = reset_control_deassert(priv->rst_parent_gio);
271 	if (ret)
272 		goto out_rst_assert;
273 
274 	if ((priv->data->is_legacy)
275 	    || (!priv->data->config0 && !priv->data->config1))
276 		return 0;
277 
278 	config0 = priv->data->config0;
279 	config1 = priv->data->config1;
280 
281 	ret = uniphier_u3hsphy_update_config(priv, &config0);
282 	if (ret)
283 		goto out_rst_assert;
284 
285 	writel(config0, priv->base + HSPHY_CFG0);
286 	writel(config1, priv->base + HSPHY_CFG1);
287 
288 	for (i = 0; i < priv->data->nparams; i++)
289 		uniphier_u3hsphy_set_param(priv, &priv->data->param[i]);
290 
291 	return 0;
292 
293 out_rst_assert:
294 	reset_control_assert(priv->rst_parent);
295 out_clk_gio_disable:
296 	clk_disable_unprepare(priv->clk_parent_gio);
297 out_clk_disable:
298 	clk_disable_unprepare(priv->clk_parent);
299 
300 	return ret;
301 }
302 
303 static int uniphier_u3hsphy_exit(struct phy *phy)
304 {
305 	struct uniphier_u3hsphy_priv *priv = phy_get_drvdata(phy);
306 
307 	reset_control_assert(priv->rst_parent_gio);
308 	reset_control_assert(priv->rst_parent);
309 	clk_disable_unprepare(priv->clk_parent_gio);
310 	clk_disable_unprepare(priv->clk_parent);
311 
312 	return 0;
313 }
314 
315 static const struct phy_ops uniphier_u3hsphy_ops = {
316 	.init           = uniphier_u3hsphy_init,
317 	.exit           = uniphier_u3hsphy_exit,
318 	.power_on       = uniphier_u3hsphy_power_on,
319 	.power_off      = uniphier_u3hsphy_power_off,
320 	.owner          = THIS_MODULE,
321 };
322 
323 static int uniphier_u3hsphy_probe(struct platform_device *pdev)
324 {
325 	struct device *dev = &pdev->dev;
326 	struct uniphier_u3hsphy_priv *priv;
327 	struct phy_provider *phy_provider;
328 	struct phy *phy;
329 
330 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
331 	if (!priv)
332 		return -ENOMEM;
333 
334 	priv->dev = dev;
335 	priv->data = of_device_get_match_data(dev);
336 	if (WARN_ON(!priv->data ||
337 		    priv->data->nparams > MAX_PHY_PARAMS))
338 		return -EINVAL;
339 
340 	priv->base = devm_platform_ioremap_resource(pdev, 0);
341 	if (IS_ERR(priv->base))
342 		return PTR_ERR(priv->base);
343 
344 	if (!priv->data->is_legacy) {
345 		priv->clk = devm_clk_get(dev, "phy");
346 		if (IS_ERR(priv->clk))
347 			return PTR_ERR(priv->clk);
348 
349 		priv->clk_ext = devm_clk_get_optional(dev, "phy-ext");
350 		if (IS_ERR(priv->clk_ext))
351 			return PTR_ERR(priv->clk_ext);
352 
353 		priv->rst = devm_reset_control_get_shared(dev, "phy");
354 		if (IS_ERR(priv->rst))
355 			return PTR_ERR(priv->rst);
356 
357 	} else {
358 		priv->clk_parent_gio = devm_clk_get(dev, "gio");
359 		if (IS_ERR(priv->clk_parent_gio))
360 			return PTR_ERR(priv->clk_parent_gio);
361 
362 		priv->rst_parent_gio =
363 			devm_reset_control_get_shared(dev, "gio");
364 		if (IS_ERR(priv->rst_parent_gio))
365 			return PTR_ERR(priv->rst_parent_gio);
366 	}
367 
368 	priv->clk_parent = devm_clk_get(dev, "link");
369 	if (IS_ERR(priv->clk_parent))
370 		return PTR_ERR(priv->clk_parent);
371 
372 	priv->rst_parent = devm_reset_control_get_shared(dev, "link");
373 	if (IS_ERR(priv->rst_parent))
374 		return PTR_ERR(priv->rst_parent);
375 
376 	priv->vbus = devm_regulator_get_optional(dev, "vbus");
377 	if (IS_ERR(priv->vbus)) {
378 		if (PTR_ERR(priv->vbus) == -EPROBE_DEFER)
379 			return PTR_ERR(priv->vbus);
380 		priv->vbus = NULL;
381 	}
382 
383 	phy = devm_phy_create(dev, dev->of_node, &uniphier_u3hsphy_ops);
384 	if (IS_ERR(phy))
385 		return PTR_ERR(phy);
386 
387 	phy_set_drvdata(phy, priv);
388 	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
389 
390 	return PTR_ERR_OR_ZERO(phy_provider);
391 }
392 
393 static const struct uniphier_u3hsphy_soc_data uniphier_pro5_data = {
394 	.is_legacy = true,
395 	.nparams = 0,
396 };
397 
398 static const struct uniphier_u3hsphy_soc_data uniphier_pxs2_data = {
399 	.is_legacy = false,
400 	.nparams = 2,
401 	.param = {
402 		{ RX_CHK_SYNC, 1 },
403 		{ RX_SYNC_SEL, 1 },
404 	},
405 };
406 
407 static const struct uniphier_u3hsphy_soc_data uniphier_ld20_data = {
408 	.is_legacy = false,
409 	.nparams = 4,
410 	.param = {
411 		{ RX_CHK_SYNC, 1 },
412 		{ RX_SYNC_SEL, 1 },
413 		{ LS_SLEW, 1 },
414 		{ FS_LS_DRV, 1 },
415 	},
416 	.trim_func = uniphier_u3hsphy_trim_ld20,
417 	.config0 = 0x92316680,
418 	.config1 = 0x00000106,
419 };
420 
421 static const struct uniphier_u3hsphy_soc_data uniphier_pxs3_data = {
422 	.is_legacy = false,
423 	.nparams = 2,
424 	.param = {
425 		{ RX_CHK_SYNC, 1 },
426 		{ RX_SYNC_SEL, 1 },
427 	},
428 	.trim_func = uniphier_u3hsphy_trim_ld20,
429 	.config0 = 0x92316680,
430 	.config1 = 0x00000106,
431 };
432 
433 static const struct of_device_id uniphier_u3hsphy_match[] = {
434 	{
435 		.compatible = "socionext,uniphier-pro5-usb3-hsphy",
436 		.data = &uniphier_pro5_data,
437 	},
438 	{
439 		.compatible = "socionext,uniphier-pxs2-usb3-hsphy",
440 		.data = &uniphier_pxs2_data,
441 	},
442 	{
443 		.compatible = "socionext,uniphier-ld20-usb3-hsphy",
444 		.data = &uniphier_ld20_data,
445 	},
446 	{
447 		.compatible = "socionext,uniphier-pxs3-usb3-hsphy",
448 		.data = &uniphier_pxs3_data,
449 	},
450 	{
451 		.compatible = "socionext,uniphier-nx1-usb3-hsphy",
452 		.data = &uniphier_pxs3_data,
453 	},
454 	{ /* sentinel */ }
455 };
456 MODULE_DEVICE_TABLE(of, uniphier_u3hsphy_match);
457 
458 static struct platform_driver uniphier_u3hsphy_driver = {
459 	.probe = uniphier_u3hsphy_probe,
460 	.driver	= {
461 		.name = "uniphier-usb3-hsphy",
462 		.of_match_table	= uniphier_u3hsphy_match,
463 	},
464 };
465 
466 module_platform_driver(uniphier_u3hsphy_driver);
467 
468 MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
469 MODULE_DESCRIPTION("UniPhier HS-PHY driver for USB3 controller");
470 MODULE_LICENSE("GPL v2");
471