1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Renesas R-Car Gen2 PHY driver
4 *
5 * Copyright (C) 2014 Renesas Solutions Corp.
6 * Copyright (C) 2014 Cogent Embedded, Inc.
7 * Copyright (C) 2019 Renesas Electronics Corp.
8 */
9
10 #include <linux/clk.h>
11 #include <linux/delay.h>
12 #include <linux/io.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/phy/phy.h>
16 #include <linux/platform_device.h>
17 #include <linux/spinlock.h>
18 #include <linux/atomic.h>
19 #include <linux/of_device.h>
20
21 #define USBHS_LPSTS 0x02
22 #define USBHS_UGCTRL 0x80
23 #define USBHS_UGCTRL2 0x84
24 #define USBHS_UGSTS 0x88 /* From technical update */
25
26 /* Low Power Status register (LPSTS) */
27 #define USBHS_LPSTS_SUSPM 0x4000
28
29 /* USB General control register (UGCTRL) */
30 #define USBHS_UGCTRL_CONNECT 0x00000004
31 #define USBHS_UGCTRL_PLLRESET 0x00000001
32
33 /* USB General control register 2 (UGCTRL2) */
34 #define USBHS_UGCTRL2_USB2SEL 0x80000000
35 #define USBHS_UGCTRL2_USB2SEL_PCI 0x00000000
36 #define USBHS_UGCTRL2_USB2SEL_USB30 0x80000000
37 #define USBHS_UGCTRL2_USB0SEL 0x00000030
38 #define USBHS_UGCTRL2_USB0SEL_PCI 0x00000010
39 #define USBHS_UGCTRL2_USB0SEL_HS_USB 0x00000030
40 #define USBHS_UGCTRL2_USB0SEL_USB20 0x00000010
41 #define USBHS_UGCTRL2_USB0SEL_HS_USB20 0x00000020
42
43 /* USB General status register (UGSTS) */
44 #define USBHS_UGSTS_LOCK 0x00000100 /* From technical update */
45
46 #define PHYS_PER_CHANNEL 2
47
48 struct rcar_gen2_phy {
49 struct phy *phy;
50 struct rcar_gen2_channel *channel;
51 int number;
52 u32 select_value;
53 };
54
55 struct rcar_gen2_channel {
56 struct device_node *of_node;
57 struct rcar_gen2_phy_driver *drv;
58 struct rcar_gen2_phy phys[PHYS_PER_CHANNEL];
59 int selected_phy;
60 u32 select_mask;
61 };
62
63 struct rcar_gen2_phy_driver {
64 void __iomem *base;
65 struct clk *clk;
66 spinlock_t lock;
67 int num_channels;
68 struct rcar_gen2_channel *channels;
69 };
70
71 struct rcar_gen2_phy_data {
72 const struct phy_ops *gen2_phy_ops;
73 const u32 (*select_value)[PHYS_PER_CHANNEL];
74 const u32 num_channels;
75 };
76
rcar_gen2_phy_init(struct phy * p)77 static int rcar_gen2_phy_init(struct phy *p)
78 {
79 struct rcar_gen2_phy *phy = phy_get_drvdata(p);
80 struct rcar_gen2_channel *channel = phy->channel;
81 struct rcar_gen2_phy_driver *drv = channel->drv;
82 unsigned long flags;
83 u32 ugctrl2;
84
85 /*
86 * Try to acquire exclusive access to PHY. The first driver calling
87 * phy_init() on a given channel wins, and all attempts to use another
88 * PHY on this channel will fail until phy_exit() is called by the first
89 * driver. Achieving this with cmpxcgh() should be SMP-safe.
90 */
91 if (cmpxchg(&channel->selected_phy, -1, phy->number) != -1)
92 return -EBUSY;
93
94 clk_prepare_enable(drv->clk);
95
96 spin_lock_irqsave(&drv->lock, flags);
97 ugctrl2 = readl(drv->base + USBHS_UGCTRL2);
98 ugctrl2 &= ~channel->select_mask;
99 ugctrl2 |= phy->select_value;
100 writel(ugctrl2, drv->base + USBHS_UGCTRL2);
101 spin_unlock_irqrestore(&drv->lock, flags);
102 return 0;
103 }
104
rcar_gen2_phy_exit(struct phy * p)105 static int rcar_gen2_phy_exit(struct phy *p)
106 {
107 struct rcar_gen2_phy *phy = phy_get_drvdata(p);
108 struct rcar_gen2_channel *channel = phy->channel;
109
110 clk_disable_unprepare(channel->drv->clk);
111
112 channel->selected_phy = -1;
113
114 return 0;
115 }
116
rcar_gen2_phy_power_on(struct phy * p)117 static int rcar_gen2_phy_power_on(struct phy *p)
118 {
119 struct rcar_gen2_phy *phy = phy_get_drvdata(p);
120 struct rcar_gen2_phy_driver *drv = phy->channel->drv;
121 void __iomem *base = drv->base;
122 unsigned long flags;
123 u32 value;
124 int err = 0, i;
125
126 /* Skip if it's not USBHS */
127 if (phy->select_value != USBHS_UGCTRL2_USB0SEL_HS_USB)
128 return 0;
129
130 spin_lock_irqsave(&drv->lock, flags);
131
132 /* Power on USBHS PHY */
133 value = readl(base + USBHS_UGCTRL);
134 value &= ~USBHS_UGCTRL_PLLRESET;
135 writel(value, base + USBHS_UGCTRL);
136
137 value = readw(base + USBHS_LPSTS);
138 value |= USBHS_LPSTS_SUSPM;
139 writew(value, base + USBHS_LPSTS);
140
141 for (i = 0; i < 20; i++) {
142 value = readl(base + USBHS_UGSTS);
143 if ((value & USBHS_UGSTS_LOCK) == USBHS_UGSTS_LOCK) {
144 value = readl(base + USBHS_UGCTRL);
145 value |= USBHS_UGCTRL_CONNECT;
146 writel(value, base + USBHS_UGCTRL);
147 goto out;
148 }
149 udelay(1);
150 }
151
152 /* Timed out waiting for the PLL lock */
153 err = -ETIMEDOUT;
154
155 out:
156 spin_unlock_irqrestore(&drv->lock, flags);
157
158 return err;
159 }
160
rcar_gen2_phy_power_off(struct phy * p)161 static int rcar_gen2_phy_power_off(struct phy *p)
162 {
163 struct rcar_gen2_phy *phy = phy_get_drvdata(p);
164 struct rcar_gen2_phy_driver *drv = phy->channel->drv;
165 void __iomem *base = drv->base;
166 unsigned long flags;
167 u32 value;
168
169 /* Skip if it's not USBHS */
170 if (phy->select_value != USBHS_UGCTRL2_USB0SEL_HS_USB)
171 return 0;
172
173 spin_lock_irqsave(&drv->lock, flags);
174
175 /* Power off USBHS PHY */
176 value = readl(base + USBHS_UGCTRL);
177 value &= ~USBHS_UGCTRL_CONNECT;
178 writel(value, base + USBHS_UGCTRL);
179
180 value = readw(base + USBHS_LPSTS);
181 value &= ~USBHS_LPSTS_SUSPM;
182 writew(value, base + USBHS_LPSTS);
183
184 value = readl(base + USBHS_UGCTRL);
185 value |= USBHS_UGCTRL_PLLRESET;
186 writel(value, base + USBHS_UGCTRL);
187
188 spin_unlock_irqrestore(&drv->lock, flags);
189
190 return 0;
191 }
192
rz_g1c_phy_power_on(struct phy * p)193 static int rz_g1c_phy_power_on(struct phy *p)
194 {
195 struct rcar_gen2_phy *phy = phy_get_drvdata(p);
196 struct rcar_gen2_phy_driver *drv = phy->channel->drv;
197 void __iomem *base = drv->base;
198 unsigned long flags;
199 u32 value;
200
201 spin_lock_irqsave(&drv->lock, flags);
202
203 /* Power on USBHS PHY */
204 value = readl(base + USBHS_UGCTRL);
205 value &= ~USBHS_UGCTRL_PLLRESET;
206 writel(value, base + USBHS_UGCTRL);
207
208 /* As per the data sheet wait 340 micro sec for power stable */
209 udelay(340);
210
211 if (phy->select_value == USBHS_UGCTRL2_USB0SEL_HS_USB20) {
212 value = readw(base + USBHS_LPSTS);
213 value |= USBHS_LPSTS_SUSPM;
214 writew(value, base + USBHS_LPSTS);
215 }
216
217 spin_unlock_irqrestore(&drv->lock, flags);
218
219 return 0;
220 }
221
rz_g1c_phy_power_off(struct phy * p)222 static int rz_g1c_phy_power_off(struct phy *p)
223 {
224 struct rcar_gen2_phy *phy = phy_get_drvdata(p);
225 struct rcar_gen2_phy_driver *drv = phy->channel->drv;
226 void __iomem *base = drv->base;
227 unsigned long flags;
228 u32 value;
229
230 spin_lock_irqsave(&drv->lock, flags);
231 /* Power off USBHS PHY */
232 if (phy->select_value == USBHS_UGCTRL2_USB0SEL_HS_USB20) {
233 value = readw(base + USBHS_LPSTS);
234 value &= ~USBHS_LPSTS_SUSPM;
235 writew(value, base + USBHS_LPSTS);
236 }
237
238 value = readl(base + USBHS_UGCTRL);
239 value |= USBHS_UGCTRL_PLLRESET;
240 writel(value, base + USBHS_UGCTRL);
241
242 spin_unlock_irqrestore(&drv->lock, flags);
243
244 return 0;
245 }
246
247 static const struct phy_ops rcar_gen2_phy_ops = {
248 .init = rcar_gen2_phy_init,
249 .exit = rcar_gen2_phy_exit,
250 .power_on = rcar_gen2_phy_power_on,
251 .power_off = rcar_gen2_phy_power_off,
252 .owner = THIS_MODULE,
253 };
254
255 static const struct phy_ops rz_g1c_phy_ops = {
256 .init = rcar_gen2_phy_init,
257 .exit = rcar_gen2_phy_exit,
258 .power_on = rz_g1c_phy_power_on,
259 .power_off = rz_g1c_phy_power_off,
260 .owner = THIS_MODULE,
261 };
262
263 static const u32 pci_select_value[][PHYS_PER_CHANNEL] = {
264 [0] = { USBHS_UGCTRL2_USB0SEL_PCI, USBHS_UGCTRL2_USB0SEL_HS_USB },
265 [2] = { USBHS_UGCTRL2_USB2SEL_PCI, USBHS_UGCTRL2_USB2SEL_USB30 },
266 };
267
268 static const u32 usb20_select_value[][PHYS_PER_CHANNEL] = {
269 { USBHS_UGCTRL2_USB0SEL_USB20, USBHS_UGCTRL2_USB0SEL_HS_USB20 },
270 };
271
272 static const struct rcar_gen2_phy_data rcar_gen2_usb_phy_data = {
273 .gen2_phy_ops = &rcar_gen2_phy_ops,
274 .select_value = pci_select_value,
275 .num_channels = ARRAY_SIZE(pci_select_value),
276 };
277
278 static const struct rcar_gen2_phy_data rz_g1c_usb_phy_data = {
279 .gen2_phy_ops = &rz_g1c_phy_ops,
280 .select_value = usb20_select_value,
281 .num_channels = ARRAY_SIZE(usb20_select_value),
282 };
283
284 static const struct of_device_id rcar_gen2_phy_match_table[] = {
285 {
286 .compatible = "renesas,usb-phy-r8a77470",
287 .data = &rz_g1c_usb_phy_data,
288 },
289 {
290 .compatible = "renesas,usb-phy-r8a7790",
291 .data = &rcar_gen2_usb_phy_data,
292 },
293 {
294 .compatible = "renesas,usb-phy-r8a7791",
295 .data = &rcar_gen2_usb_phy_data,
296 },
297 {
298 .compatible = "renesas,usb-phy-r8a7794",
299 .data = &rcar_gen2_usb_phy_data,
300 },
301 {
302 .compatible = "renesas,rcar-gen2-usb-phy",
303 .data = &rcar_gen2_usb_phy_data,
304 },
305 { /* sentinel */ },
306 };
307 MODULE_DEVICE_TABLE(of, rcar_gen2_phy_match_table);
308
rcar_gen2_phy_xlate(struct device * dev,struct of_phandle_args * args)309 static struct phy *rcar_gen2_phy_xlate(struct device *dev,
310 struct of_phandle_args *args)
311 {
312 struct rcar_gen2_phy_driver *drv;
313 struct device_node *np = args->np;
314 int i;
315
316 drv = dev_get_drvdata(dev);
317 if (!drv)
318 return ERR_PTR(-EINVAL);
319
320 for (i = 0; i < drv->num_channels; i++) {
321 if (np == drv->channels[i].of_node)
322 break;
323 }
324
325 if (i >= drv->num_channels || args->args[0] >= 2)
326 return ERR_PTR(-ENODEV);
327
328 return drv->channels[i].phys[args->args[0]].phy;
329 }
330
331 static const u32 select_mask[] = {
332 [0] = USBHS_UGCTRL2_USB0SEL,
333 [2] = USBHS_UGCTRL2_USB2SEL,
334 };
335
rcar_gen2_phy_probe(struct platform_device * pdev)336 static int rcar_gen2_phy_probe(struct platform_device *pdev)
337 {
338 struct device *dev = &pdev->dev;
339 struct rcar_gen2_phy_driver *drv;
340 struct phy_provider *provider;
341 struct device_node *np;
342 void __iomem *base;
343 struct clk *clk;
344 const struct rcar_gen2_phy_data *data;
345 int i = 0;
346
347 if (!dev->of_node) {
348 dev_err(dev,
349 "This driver is required to be instantiated from device tree\n");
350 return -EINVAL;
351 }
352
353 clk = devm_clk_get(dev, "usbhs");
354 if (IS_ERR(clk)) {
355 dev_err(dev, "Can't get USBHS clock\n");
356 return PTR_ERR(clk);
357 }
358
359 base = devm_platform_ioremap_resource(pdev, 0);
360 if (IS_ERR(base))
361 return PTR_ERR(base);
362
363 drv = devm_kzalloc(dev, sizeof(*drv), GFP_KERNEL);
364 if (!drv)
365 return -ENOMEM;
366
367 spin_lock_init(&drv->lock);
368
369 drv->clk = clk;
370 drv->base = base;
371
372 data = of_device_get_match_data(dev);
373 if (!data)
374 return -EINVAL;
375
376 drv->num_channels = of_get_child_count(dev->of_node);
377 drv->channels = devm_kcalloc(dev, drv->num_channels,
378 sizeof(struct rcar_gen2_channel),
379 GFP_KERNEL);
380 if (!drv->channels)
381 return -ENOMEM;
382
383 for_each_child_of_node(dev->of_node, np) {
384 struct rcar_gen2_channel *channel = drv->channels + i;
385 u32 channel_num;
386 int error, n;
387
388 channel->of_node = np;
389 channel->drv = drv;
390 channel->selected_phy = -1;
391
392 error = of_property_read_u32(np, "reg", &channel_num);
393 if (error || channel_num >= data->num_channels) {
394 dev_err(dev, "Invalid \"reg\" property\n");
395 of_node_put(np);
396 return error;
397 }
398 channel->select_mask = select_mask[channel_num];
399
400 for (n = 0; n < PHYS_PER_CHANNEL; n++) {
401 struct rcar_gen2_phy *phy = &channel->phys[n];
402
403 phy->channel = channel;
404 phy->number = n;
405 phy->select_value = data->select_value[channel_num][n];
406
407 phy->phy = devm_phy_create(dev, NULL,
408 data->gen2_phy_ops);
409 if (IS_ERR(phy->phy)) {
410 dev_err(dev, "Failed to create PHY\n");
411 of_node_put(np);
412 return PTR_ERR(phy->phy);
413 }
414 phy_set_drvdata(phy->phy, phy);
415 }
416
417 i++;
418 }
419
420 provider = devm_of_phy_provider_register(dev, rcar_gen2_phy_xlate);
421 if (IS_ERR(provider)) {
422 dev_err(dev, "Failed to register PHY provider\n");
423 return PTR_ERR(provider);
424 }
425
426 dev_set_drvdata(dev, drv);
427
428 return 0;
429 }
430
431 static struct platform_driver rcar_gen2_phy_driver = {
432 .driver = {
433 .name = "phy_rcar_gen2",
434 .of_match_table = rcar_gen2_phy_match_table,
435 },
436 .probe = rcar_gen2_phy_probe,
437 };
438
439 module_platform_driver(rcar_gen2_phy_driver);
440
441 MODULE_LICENSE("GPL v2");
442 MODULE_DESCRIPTION("Renesas R-Car Gen2 PHY");
443 MODULE_AUTHOR("Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>");
444