xref: /openbmc/linux/drivers/usb/dwc3/dwc3-xilinx.c (revision 16f6ccde74a6f8538c62f127f17207c75f4dba7a)
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_platform.h>
18 #include <linux/pm_runtime.h>
19 #include <linux/reset.h>
20 #include <linux/of_address.h>
21 #include <linux/delay.h>
22 #include <linux/firmware/xlnx-zynqmp.h>
23 #include <linux/io.h>
24 
25 #include <linux/phy/phy.h>
26 
27 /* USB phy reset mask register */
28 #define XLNX_USB_PHY_RST_EN			0x001C
29 #define XLNX_PHY_RST_MASK			0x1
30 
31 /* Xilinx USB 3.0 IP Register */
32 #define XLNX_USB_TRAFFIC_ROUTE_CONFIG		0x005C
33 #define XLNX_USB_TRAFFIC_ROUTE_FPD		0x1
34 
35 /* Versal USB Reset ID */
36 #define VERSAL_USB_RESET_ID			0xC104036
37 
38 #define XLNX_USB_FPD_PIPE_CLK			0x7c
39 #define PIPE_CLK_DESELECT			1
40 #define PIPE_CLK_SELECT				0
41 #define XLNX_USB_FPD_POWER_PRSNT		0x80
42 #define FPD_POWER_PRSNT_OPTION			BIT(0)
43 
44 struct dwc3_xlnx {
45 	int				num_clocks;
46 	struct clk_bulk_data		*clks;
47 	struct device			*dev;
48 	void __iomem			*regs;
49 	int				(*pltfm_init)(struct dwc3_xlnx *data);
50 	struct phy			*usb3_phy;
51 };
52 
dwc3_xlnx_mask_phy_rst(struct dwc3_xlnx * priv_data,bool mask)53 static void dwc3_xlnx_mask_phy_rst(struct dwc3_xlnx *priv_data, bool mask)
54 {
55 	u32 reg;
56 
57 	/*
58 	 * Enable or disable ULPI PHY reset from USB Controller.
59 	 * This does not actually reset the phy, but just controls
60 	 * whether USB controller can or cannot reset ULPI PHY.
61 	 */
62 	reg = readl(priv_data->regs + XLNX_USB_PHY_RST_EN);
63 
64 	if (mask)
65 		reg &= ~XLNX_PHY_RST_MASK;
66 	else
67 		reg |= XLNX_PHY_RST_MASK;
68 
69 	writel(reg, priv_data->regs + XLNX_USB_PHY_RST_EN);
70 }
71 
dwc3_xlnx_init_versal(struct dwc3_xlnx * priv_data)72 static int dwc3_xlnx_init_versal(struct dwc3_xlnx *priv_data)
73 {
74 	struct device		*dev = priv_data->dev;
75 	int			ret;
76 
77 	dwc3_xlnx_mask_phy_rst(priv_data, false);
78 
79 	/* Assert and De-assert reset */
80 	ret = zynqmp_pm_reset_assert(VERSAL_USB_RESET_ID,
81 				     PM_RESET_ACTION_ASSERT);
82 	if (ret < 0) {
83 		dev_err_probe(dev, ret, "failed to assert Reset\n");
84 		return ret;
85 	}
86 
87 	ret = zynqmp_pm_reset_assert(VERSAL_USB_RESET_ID,
88 				     PM_RESET_ACTION_RELEASE);
89 	if (ret < 0) {
90 		dev_err_probe(dev, ret, "failed to De-assert Reset\n");
91 		return ret;
92 	}
93 
94 	dwc3_xlnx_mask_phy_rst(priv_data, true);
95 
96 	return 0;
97 }
98 
dwc3_xlnx_init_zynqmp(struct dwc3_xlnx * priv_data)99 static int dwc3_xlnx_init_zynqmp(struct dwc3_xlnx *priv_data)
100 {
101 	struct device		*dev = priv_data->dev;
102 	struct reset_control	*crst, *hibrst, *apbrst;
103 	struct gpio_desc	*reset_gpio;
104 	int			ret = 0;
105 	u32			reg;
106 
107 	priv_data->usb3_phy = devm_phy_optional_get(dev, "usb3-phy");
108 	if (IS_ERR(priv_data->usb3_phy)) {
109 		ret = PTR_ERR(priv_data->usb3_phy);
110 		dev_err_probe(dev, ret,
111 			      "failed to get USB3 PHY\n");
112 		goto err;
113 	}
114 
115 	/*
116 	 * The following core resets are not required unless a USB3 PHY
117 	 * is used, and the subsequent register settings are not required
118 	 * unless a core reset is performed (they should be set properly
119 	 * by the first-stage boot loader, but may be reverted by a core
120 	 * reset). They may also break the configuration if USB3 is actually
121 	 * in use but the usb3-phy entry is missing from the device tree.
122 	 * Therefore, skip these operations in this case.
123 	 */
124 	if (!priv_data->usb3_phy) {
125 		/* Deselect the PIPE Clock Select bit in FPD PIPE Clock register */
126 		writel(PIPE_CLK_DESELECT, priv_data->regs + XLNX_USB_FPD_PIPE_CLK);
127 		goto skip_usb3_phy;
128 	}
129 
130 	crst = devm_reset_control_get_exclusive(dev, "usb_crst");
131 	if (IS_ERR(crst)) {
132 		ret = PTR_ERR(crst);
133 		dev_err_probe(dev, ret,
134 			      "failed to get core reset signal\n");
135 		goto err;
136 	}
137 
138 	hibrst = devm_reset_control_get_exclusive(dev, "usb_hibrst");
139 	if (IS_ERR(hibrst)) {
140 		ret = PTR_ERR(hibrst);
141 		dev_err_probe(dev, ret,
142 			      "failed to get hibernation reset signal\n");
143 		goto err;
144 	}
145 
146 	apbrst = devm_reset_control_get_exclusive(dev, "usb_apbrst");
147 	if (IS_ERR(apbrst)) {
148 		ret = PTR_ERR(apbrst);
149 		dev_err_probe(dev, ret,
150 			      "failed to get APB reset signal\n");
151 		goto err;
152 	}
153 
154 	ret = reset_control_assert(crst);
155 	if (ret < 0) {
156 		dev_err(dev, "Failed to assert core reset\n");
157 		goto err;
158 	}
159 
160 	ret = reset_control_assert(hibrst);
161 	if (ret < 0) {
162 		dev_err(dev, "Failed to assert hibernation reset\n");
163 		goto err;
164 	}
165 
166 	ret = reset_control_assert(apbrst);
167 	if (ret < 0) {
168 		dev_err(dev, "Failed to assert APB reset\n");
169 		goto err;
170 	}
171 
172 	ret = phy_init(priv_data->usb3_phy);
173 	if (ret < 0) {
174 		phy_exit(priv_data->usb3_phy);
175 		goto err;
176 	}
177 
178 	ret = reset_control_deassert(apbrst);
179 	if (ret < 0) {
180 		dev_err(dev, "Failed to release APB reset\n");
181 		goto err;
182 	}
183 
184 	/* Set PIPE Power Present signal in FPD Power Present Register*/
185 	writel(FPD_POWER_PRSNT_OPTION, priv_data->regs + XLNX_USB_FPD_POWER_PRSNT);
186 
187 	/* Set the PIPE Clock Select bit in FPD PIPE Clock register */
188 	writel(PIPE_CLK_SELECT, priv_data->regs + XLNX_USB_FPD_PIPE_CLK);
189 
190 	ret = reset_control_deassert(crst);
191 	if (ret < 0) {
192 		dev_err(dev, "Failed to release core reset\n");
193 		goto err;
194 	}
195 
196 	ret = reset_control_deassert(hibrst);
197 	if (ret < 0) {
198 		dev_err(dev, "Failed to release hibernation reset\n");
199 		goto err;
200 	}
201 
202 	ret = phy_power_on(priv_data->usb3_phy);
203 	if (ret < 0) {
204 		phy_exit(priv_data->usb3_phy);
205 		goto err;
206 	}
207 
208 skip_usb3_phy:
209 	/* ulpi reset via gpio-modepin or gpio-framework driver */
210 	reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
211 	if (IS_ERR(reset_gpio)) {
212 		return dev_err_probe(dev, PTR_ERR(reset_gpio),
213 				     "Failed to request reset GPIO\n");
214 	}
215 
216 	if (reset_gpio) {
217 		/* Toggle ulpi to reset the phy. */
218 		gpiod_set_value_cansleep(reset_gpio, 1);
219 		usleep_range(5000, 10000);
220 		gpiod_set_value_cansleep(reset_gpio, 0);
221 		usleep_range(5000, 10000);
222 	}
223 
224 	/*
225 	 * This routes the USB DMA traffic to go through FPD path instead
226 	 * of reaching DDR directly. This traffic routing is needed to
227 	 * make SMMU and CCI work with USB DMA.
228 	 */
229 	if (of_dma_is_coherent(dev->of_node) || device_iommu_mapped(dev)) {
230 		reg = readl(priv_data->regs + XLNX_USB_TRAFFIC_ROUTE_CONFIG);
231 		reg |= XLNX_USB_TRAFFIC_ROUTE_FPD;
232 		writel(reg, priv_data->regs + XLNX_USB_TRAFFIC_ROUTE_CONFIG);
233 	}
234 
235 err:
236 	return ret;
237 }
238 
239 static const struct of_device_id dwc3_xlnx_of_match[] = {
240 	{
241 		.compatible = "xlnx,zynqmp-dwc3",
242 		.data = &dwc3_xlnx_init_zynqmp,
243 	},
244 	{
245 		.compatible = "xlnx,versal-dwc3",
246 		.data = &dwc3_xlnx_init_versal,
247 	},
248 	{ /* Sentinel */ }
249 };
250 MODULE_DEVICE_TABLE(of, dwc3_xlnx_of_match);
251 
dwc3_xlnx_probe(struct platform_device * pdev)252 static int dwc3_xlnx_probe(struct platform_device *pdev)
253 {
254 	struct dwc3_xlnx		*priv_data;
255 	struct device			*dev = &pdev->dev;
256 	struct device_node		*np = dev->of_node;
257 	const struct of_device_id	*match;
258 	void __iomem			*regs;
259 	int				ret;
260 
261 	priv_data = devm_kzalloc(dev, sizeof(*priv_data), GFP_KERNEL);
262 	if (!priv_data)
263 		return -ENOMEM;
264 
265 	regs = devm_platform_ioremap_resource(pdev, 0);
266 	if (IS_ERR(regs)) {
267 		ret = PTR_ERR(regs);
268 		dev_err_probe(dev, ret, "failed to map registers\n");
269 		return ret;
270 	}
271 
272 	match = of_match_node(dwc3_xlnx_of_match, pdev->dev.of_node);
273 
274 	priv_data->pltfm_init = match->data;
275 	priv_data->regs = regs;
276 	priv_data->dev = dev;
277 
278 	platform_set_drvdata(pdev, priv_data);
279 
280 	ret = devm_clk_bulk_get_all(priv_data->dev, &priv_data->clks);
281 	if (ret < 0)
282 		return ret;
283 
284 	priv_data->num_clocks = ret;
285 
286 	ret = clk_bulk_prepare_enable(priv_data->num_clocks, priv_data->clks);
287 	if (ret)
288 		return ret;
289 
290 	ret = priv_data->pltfm_init(priv_data);
291 	if (ret)
292 		goto err_clk_put;
293 
294 	ret = of_platform_populate(np, NULL, NULL, dev);
295 	if (ret)
296 		goto err_clk_put;
297 
298 	pm_runtime_set_active(dev);
299 	pm_runtime_enable(dev);
300 	pm_suspend_ignore_children(dev, false);
301 	pm_runtime_get_sync(dev);
302 
303 	return 0;
304 
305 err_clk_put:
306 	clk_bulk_disable_unprepare(priv_data->num_clocks, priv_data->clks);
307 
308 	return ret;
309 }
310 
dwc3_xlnx_remove(struct platform_device * pdev)311 static void dwc3_xlnx_remove(struct platform_device *pdev)
312 {
313 	struct dwc3_xlnx	*priv_data = platform_get_drvdata(pdev);
314 	struct device		*dev = &pdev->dev;
315 
316 	of_platform_depopulate(dev);
317 
318 	clk_bulk_disable_unprepare(priv_data->num_clocks, priv_data->clks);
319 	priv_data->num_clocks = 0;
320 
321 	pm_runtime_disable(dev);
322 	pm_runtime_put_noidle(dev);
323 	pm_runtime_set_suspended(dev);
324 }
325 
dwc3_xlnx_runtime_suspend(struct device * dev)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 
dwc3_xlnx_runtime_resume(struct device * dev)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 
dwc3_xlnx_runtime_idle(struct device * dev)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 
dwc3_xlnx_suspend(struct device * dev)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 
dwc3_xlnx_resume(struct device * dev)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_new	= 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