xref: /openbmc/linux/drivers/usb/dwc3/dwc3-xilinx.c (revision 31d5f934)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * dwc3-xilinx.c - Xilinx DWC3 controller specific glue driver
4  *
5  * Authors: Manish Narani <manish.narani@xilinx.com>
6  *          Anurag Kumar Vulisha <anurag.kumar.vulisha@xilinx.com>
7  */
8 
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <linux/slab.h>
12 #include <linux/clk.h>
13 #include <linux/of.h>
14 #include <linux/platform_device.h>
15 #include <linux/dma-mapping.h>
16 #include <linux/gpio/consumer.h>
17 #include <linux/of_gpio.h>
18 #include <linux/of_platform.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/reset.h>
21 #include <linux/of_address.h>
22 #include <linux/delay.h>
23 #include <linux/firmware/xlnx-zynqmp.h>
24 #include <linux/io.h>
25 
26 #include <linux/phy/phy.h>
27 
28 /* USB phy reset mask register */
29 #define XLNX_USB_PHY_RST_EN			0x001C
30 #define XLNX_PHY_RST_MASK			0x1
31 
32 /* Xilinx USB 3.0 IP Register */
33 #define XLNX_USB_TRAFFIC_ROUTE_CONFIG		0x005C
34 #define XLNX_USB_TRAFFIC_ROUTE_FPD		0x1
35 
36 /* Versal USB Reset ID */
37 #define VERSAL_USB_RESET_ID			0xC104036
38 
39 #define XLNX_USB_FPD_PIPE_CLK			0x7c
40 #define PIPE_CLK_DESELECT			1
41 #define PIPE_CLK_SELECT				0
42 #define XLNX_USB_FPD_POWER_PRSNT		0x80
43 #define FPD_POWER_PRSNT_OPTION			BIT(0)
44 
45 struct dwc3_xlnx {
46 	int				num_clocks;
47 	struct clk_bulk_data		*clks;
48 	struct device			*dev;
49 	void __iomem			*regs;
50 	int				(*pltfm_init)(struct dwc3_xlnx *data);
51 	struct phy			*usb3_phy;
52 };
53 
54 static void dwc3_xlnx_mask_phy_rst(struct dwc3_xlnx *priv_data, bool mask)
55 {
56 	u32 reg;
57 
58 	/*
59 	 * Enable or disable ULPI PHY reset from USB Controller.
60 	 * This does not actually reset the phy, but just controls
61 	 * whether USB controller can or cannot reset ULPI PHY.
62 	 */
63 	reg = readl(priv_data->regs + XLNX_USB_PHY_RST_EN);
64 
65 	if (mask)
66 		reg &= ~XLNX_PHY_RST_MASK;
67 	else
68 		reg |= XLNX_PHY_RST_MASK;
69 
70 	writel(reg, priv_data->regs + XLNX_USB_PHY_RST_EN);
71 }
72 
73 static int dwc3_xlnx_init_versal(struct dwc3_xlnx *priv_data)
74 {
75 	struct device		*dev = priv_data->dev;
76 	int			ret;
77 
78 	dwc3_xlnx_mask_phy_rst(priv_data, false);
79 
80 	/* Assert and De-assert reset */
81 	ret = zynqmp_pm_reset_assert(VERSAL_USB_RESET_ID,
82 				     PM_RESET_ACTION_ASSERT);
83 	if (ret < 0) {
84 		dev_err_probe(dev, ret, "failed to assert Reset\n");
85 		return ret;
86 	}
87 
88 	ret = zynqmp_pm_reset_assert(VERSAL_USB_RESET_ID,
89 				     PM_RESET_ACTION_RELEASE);
90 	if (ret < 0) {
91 		dev_err_probe(dev, ret, "failed to De-assert Reset\n");
92 		return ret;
93 	}
94 
95 	dwc3_xlnx_mask_phy_rst(priv_data, true);
96 
97 	return 0;
98 }
99 
100 static int dwc3_xlnx_init_zynqmp(struct dwc3_xlnx *priv_data)
101 {
102 	struct device		*dev = priv_data->dev;
103 	struct reset_control	*crst, *hibrst, *apbrst;
104 	struct gpio_desc	*reset_gpio;
105 	int			ret = 0;
106 	u32			reg;
107 
108 	priv_data->usb3_phy = devm_phy_optional_get(dev, "usb3-phy");
109 	if (IS_ERR(priv_data->usb3_phy)) {
110 		ret = PTR_ERR(priv_data->usb3_phy);
111 		dev_err_probe(dev, ret,
112 			      "failed to get USB3 PHY\n");
113 		goto err;
114 	}
115 
116 	/*
117 	 * The following core resets are not required unless a USB3 PHY
118 	 * is used, and the subsequent register settings are not required
119 	 * unless a core reset is performed (they should be set properly
120 	 * by the first-stage boot loader, but may be reverted by a core
121 	 * reset). They may also break the configuration if USB3 is actually
122 	 * in use but the usb3-phy entry is missing from the device tree.
123 	 * Therefore, skip these operations in this case.
124 	 */
125 	if (!priv_data->usb3_phy)
126 		goto skip_usb3_phy;
127 
128 	crst = devm_reset_control_get_exclusive(dev, "usb_crst");
129 	if (IS_ERR(crst)) {
130 		ret = PTR_ERR(crst);
131 		dev_err_probe(dev, ret,
132 			      "failed to get core reset signal\n");
133 		goto err;
134 	}
135 
136 	hibrst = devm_reset_control_get_exclusive(dev, "usb_hibrst");
137 	if (IS_ERR(hibrst)) {
138 		ret = PTR_ERR(hibrst);
139 		dev_err_probe(dev, ret,
140 			      "failed to get hibernation reset signal\n");
141 		goto err;
142 	}
143 
144 	apbrst = devm_reset_control_get_exclusive(dev, "usb_apbrst");
145 	if (IS_ERR(apbrst)) {
146 		ret = PTR_ERR(apbrst);
147 		dev_err_probe(dev, ret,
148 			      "failed to get APB reset signal\n");
149 		goto err;
150 	}
151 
152 	ret = reset_control_assert(crst);
153 	if (ret < 0) {
154 		dev_err(dev, "Failed to assert core reset\n");
155 		goto err;
156 	}
157 
158 	ret = reset_control_assert(hibrst);
159 	if (ret < 0) {
160 		dev_err(dev, "Failed to assert hibernation reset\n");
161 		goto err;
162 	}
163 
164 	ret = reset_control_assert(apbrst);
165 	if (ret < 0) {
166 		dev_err(dev, "Failed to assert APB reset\n");
167 		goto err;
168 	}
169 
170 	ret = phy_init(priv_data->usb3_phy);
171 	if (ret < 0) {
172 		phy_exit(priv_data->usb3_phy);
173 		goto err;
174 	}
175 
176 	ret = reset_control_deassert(apbrst);
177 	if (ret < 0) {
178 		dev_err(dev, "Failed to release APB reset\n");
179 		goto err;
180 	}
181 
182 	/* Set PIPE Power Present signal in FPD Power Present Register*/
183 	writel(FPD_POWER_PRSNT_OPTION, priv_data->regs + XLNX_USB_FPD_POWER_PRSNT);
184 
185 	/* Set the PIPE Clock Select bit in FPD PIPE Clock register */
186 	writel(PIPE_CLK_SELECT, priv_data->regs + XLNX_USB_FPD_PIPE_CLK);
187 
188 	ret = reset_control_deassert(crst);
189 	if (ret < 0) {
190 		dev_err(dev, "Failed to release core reset\n");
191 		goto err;
192 	}
193 
194 	ret = reset_control_deassert(hibrst);
195 	if (ret < 0) {
196 		dev_err(dev, "Failed to release hibernation reset\n");
197 		goto err;
198 	}
199 
200 	ret = phy_power_on(priv_data->usb3_phy);
201 	if (ret < 0) {
202 		phy_exit(priv_data->usb3_phy);
203 		goto err;
204 	}
205 
206 skip_usb3_phy:
207 	/* ulpi reset via gpio-modepin or gpio-framework driver */
208 	reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
209 	if (IS_ERR(reset_gpio)) {
210 		return dev_err_probe(dev, PTR_ERR(reset_gpio),
211 				     "Failed to request reset GPIO\n");
212 	}
213 
214 	if (reset_gpio) {
215 		/* Toggle ulpi to reset the phy. */
216 		gpiod_set_value_cansleep(reset_gpio, 1);
217 		usleep_range(5000, 10000);
218 		gpiod_set_value_cansleep(reset_gpio, 0);
219 		usleep_range(5000, 10000);
220 	}
221 
222 	/*
223 	 * This routes the USB DMA traffic to go through FPD path instead
224 	 * of reaching DDR directly. This traffic routing is needed to
225 	 * make SMMU and CCI work with USB DMA.
226 	 */
227 	if (of_dma_is_coherent(dev->of_node) || device_iommu_mapped(dev)) {
228 		reg = readl(priv_data->regs + XLNX_USB_TRAFFIC_ROUTE_CONFIG);
229 		reg |= XLNX_USB_TRAFFIC_ROUTE_FPD;
230 		writel(reg, priv_data->regs + XLNX_USB_TRAFFIC_ROUTE_CONFIG);
231 	}
232 
233 err:
234 	return ret;
235 }
236 
237 static const struct of_device_id dwc3_xlnx_of_match[] = {
238 	{
239 		.compatible = "xlnx,zynqmp-dwc3",
240 		.data = &dwc3_xlnx_init_zynqmp,
241 	},
242 	{
243 		.compatible = "xlnx,versal-dwc3",
244 		.data = &dwc3_xlnx_init_versal,
245 	},
246 	{ /* Sentinel */ }
247 };
248 MODULE_DEVICE_TABLE(of, dwc3_xlnx_of_match);
249 
250 static int dwc3_xlnx_probe(struct platform_device *pdev)
251 {
252 	struct dwc3_xlnx		*priv_data;
253 	struct device			*dev = &pdev->dev;
254 	struct device_node		*np = dev->of_node;
255 	const struct of_device_id	*match;
256 	void __iomem			*regs;
257 	int				ret;
258 
259 	priv_data = devm_kzalloc(dev, sizeof(*priv_data), GFP_KERNEL);
260 	if (!priv_data)
261 		return -ENOMEM;
262 
263 	regs = devm_platform_ioremap_resource(pdev, 0);
264 	if (IS_ERR(regs)) {
265 		ret = PTR_ERR(regs);
266 		dev_err_probe(dev, ret, "failed to map registers\n");
267 		return ret;
268 	}
269 
270 	match = of_match_node(dwc3_xlnx_of_match, pdev->dev.of_node);
271 
272 	priv_data->pltfm_init = match->data;
273 	priv_data->regs = regs;
274 	priv_data->dev = dev;
275 
276 	platform_set_drvdata(pdev, priv_data);
277 
278 	ret = devm_clk_bulk_get_all(priv_data->dev, &priv_data->clks);
279 	if (ret < 0)
280 		return ret;
281 
282 	priv_data->num_clocks = ret;
283 
284 	ret = clk_bulk_prepare_enable(priv_data->num_clocks, priv_data->clks);
285 	if (ret)
286 		return ret;
287 
288 	ret = priv_data->pltfm_init(priv_data);
289 	if (ret)
290 		goto err_clk_put;
291 
292 	ret = of_platform_populate(np, NULL, NULL, dev);
293 	if (ret)
294 		goto err_clk_put;
295 
296 	pm_runtime_set_active(dev);
297 	pm_runtime_enable(dev);
298 	pm_suspend_ignore_children(dev, false);
299 	pm_runtime_get_sync(dev);
300 
301 	return 0;
302 
303 err_clk_put:
304 	clk_bulk_disable_unprepare(priv_data->num_clocks, priv_data->clks);
305 
306 	return ret;
307 }
308 
309 static int dwc3_xlnx_remove(struct platform_device *pdev)
310 {
311 	struct dwc3_xlnx	*priv_data = platform_get_drvdata(pdev);
312 	struct device		*dev = &pdev->dev;
313 
314 	of_platform_depopulate(dev);
315 
316 	clk_bulk_disable_unprepare(priv_data->num_clocks, priv_data->clks);
317 	priv_data->num_clocks = 0;
318 
319 	pm_runtime_disable(dev);
320 	pm_runtime_put_noidle(dev);
321 	pm_runtime_set_suspended(dev);
322 
323 	return 0;
324 }
325 
326 static int __maybe_unused dwc3_xlnx_runtime_suspend(struct device *dev)
327 {
328 	struct dwc3_xlnx *priv_data = dev_get_drvdata(dev);
329 
330 	clk_bulk_disable(priv_data->num_clocks, priv_data->clks);
331 
332 	return 0;
333 }
334 
335 static int __maybe_unused dwc3_xlnx_runtime_resume(struct device *dev)
336 {
337 	struct dwc3_xlnx *priv_data = dev_get_drvdata(dev);
338 
339 	return clk_bulk_enable(priv_data->num_clocks, priv_data->clks);
340 }
341 
342 static int __maybe_unused dwc3_xlnx_runtime_idle(struct device *dev)
343 {
344 	pm_runtime_mark_last_busy(dev);
345 	pm_runtime_autosuspend(dev);
346 
347 	return 0;
348 }
349 
350 static int __maybe_unused dwc3_xlnx_suspend(struct device *dev)
351 {
352 	struct dwc3_xlnx *priv_data = dev_get_drvdata(dev);
353 
354 	phy_exit(priv_data->usb3_phy);
355 
356 	/* Disable the clocks */
357 	clk_bulk_disable(priv_data->num_clocks, priv_data->clks);
358 
359 	return 0;
360 }
361 
362 static int __maybe_unused dwc3_xlnx_resume(struct device *dev)
363 {
364 	struct dwc3_xlnx *priv_data = dev_get_drvdata(dev);
365 	int ret;
366 
367 	ret = clk_bulk_enable(priv_data->num_clocks, priv_data->clks);
368 	if (ret)
369 		return ret;
370 
371 	ret = phy_init(priv_data->usb3_phy);
372 	if (ret < 0)
373 		return ret;
374 
375 	ret = phy_power_on(priv_data->usb3_phy);
376 	if (ret < 0) {
377 		phy_exit(priv_data->usb3_phy);
378 		return ret;
379 	}
380 
381 	return 0;
382 }
383 
384 static const struct dev_pm_ops dwc3_xlnx_dev_pm_ops = {
385 	SET_SYSTEM_SLEEP_PM_OPS(dwc3_xlnx_suspend, dwc3_xlnx_resume)
386 	SET_RUNTIME_PM_OPS(dwc3_xlnx_runtime_suspend,
387 			   dwc3_xlnx_runtime_resume, dwc3_xlnx_runtime_idle)
388 };
389 
390 static struct platform_driver dwc3_xlnx_driver = {
391 	.probe		= dwc3_xlnx_probe,
392 	.remove		= dwc3_xlnx_remove,
393 	.driver		= {
394 		.name		= "dwc3-xilinx",
395 		.of_match_table	= dwc3_xlnx_of_match,
396 		.pm		= &dwc3_xlnx_dev_pm_ops,
397 	},
398 };
399 
400 module_platform_driver(dwc3_xlnx_driver);
401 
402 MODULE_LICENSE("GPL v2");
403 MODULE_DESCRIPTION("Xilinx DWC3 controller specific glue driver");
404 MODULE_AUTHOR("Manish Narani <manish.narani@xilinx.com>");
405 MODULE_AUTHOR("Anurag Kumar Vulisha <anurag.kumar.vulisha@xilinx.com>");
406