xref: /linux/drivers/usb/dwc3/dwc3-xilinx.c (revision 4eee1520ea845a6d6d82e85498d9412419560871)
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 /* USB 2.0 IP Register */
36 #define XLNX_USB2_TRAFFIC_ROUTE_CONFIG		0x0044
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_set_coherency(struct dwc3_xlnx * priv_data,u32 coherency_offset)72 static void dwc3_xlnx_set_coherency(struct dwc3_xlnx *priv_data, u32 coherency_offset)
73 {
74 	struct device		*dev = priv_data->dev;
75 	u32			reg;
76 
77 	/*
78 	 * This routes the USB DMA traffic to go through FPD path instead
79 	 * of reaching DDR directly. This traffic routing is needed to
80 	 * make SMMU and CCI work with USB DMA.
81 	 */
82 	if (of_dma_is_coherent(dev->of_node) || device_iommu_mapped(dev)) {
83 		reg = readl(priv_data->regs + coherency_offset);
84 		reg |= XLNX_USB_TRAFFIC_ROUTE_FPD;
85 		writel(reg, priv_data->regs + coherency_offset);
86 	}
87 }
88 
dwc3_xlnx_init_versal(struct dwc3_xlnx * priv_data)89 static int dwc3_xlnx_init_versal(struct dwc3_xlnx *priv_data)
90 {
91 	struct device		*dev = priv_data->dev;
92 	struct reset_control	*crst;
93 	int			ret;
94 
95 	crst = devm_reset_control_get_exclusive(dev, NULL);
96 	if (IS_ERR(crst))
97 		return dev_err_probe(dev, PTR_ERR(crst), "failed to get reset signal\n");
98 
99 	dwc3_xlnx_mask_phy_rst(priv_data, false);
100 
101 	/* Assert and De-assert reset */
102 	ret = reset_control_assert(crst);
103 	if (ret < 0) {
104 		dev_err_probe(dev, ret, "failed to assert Reset\n");
105 		return ret;
106 	}
107 
108 	ret = reset_control_deassert(crst);
109 	if (ret < 0) {
110 		dev_err_probe(dev, ret, "failed to De-assert Reset\n");
111 		return ret;
112 	}
113 
114 	dwc3_xlnx_mask_phy_rst(priv_data, true);
115 	dwc3_xlnx_set_coherency(priv_data, XLNX_USB2_TRAFFIC_ROUTE_CONFIG);
116 
117 	return 0;
118 }
119 
dwc3_xlnx_init_zynqmp(struct dwc3_xlnx * priv_data)120 static int dwc3_xlnx_init_zynqmp(struct dwc3_xlnx *priv_data)
121 {
122 	struct device		*dev = priv_data->dev;
123 	struct reset_control	*crst, *hibrst, *apbrst;
124 	struct gpio_desc	*reset_gpio;
125 	int			ret = 0;
126 
127 	priv_data->usb3_phy = devm_phy_optional_get(dev, "usb3-phy");
128 	if (IS_ERR(priv_data->usb3_phy)) {
129 		ret = PTR_ERR(priv_data->usb3_phy);
130 		dev_err_probe(dev, ret,
131 			      "failed to get USB3 PHY\n");
132 		goto err;
133 	}
134 
135 	/*
136 	 * The following core resets are not required unless a USB3 PHY
137 	 * is used, and the subsequent register settings are not required
138 	 * unless a core reset is performed (they should be set properly
139 	 * by the first-stage boot loader, but may be reverted by a core
140 	 * reset). They may also break the configuration if USB3 is actually
141 	 * in use but the usb3-phy entry is missing from the device tree.
142 	 * Therefore, skip these operations in this case.
143 	 */
144 	if (!priv_data->usb3_phy) {
145 		/* Deselect the PIPE Clock Select bit in FPD PIPE Clock register */
146 		writel(PIPE_CLK_DESELECT, priv_data->regs + XLNX_USB_FPD_PIPE_CLK);
147 		goto skip_usb3_phy;
148 	}
149 
150 	crst = devm_reset_control_get_exclusive(dev, "usb_crst");
151 	if (IS_ERR(crst)) {
152 		ret = PTR_ERR(crst);
153 		dev_err_probe(dev, ret,
154 			      "failed to get core reset signal\n");
155 		goto err;
156 	}
157 
158 	hibrst = devm_reset_control_get_exclusive(dev, "usb_hibrst");
159 	if (IS_ERR(hibrst)) {
160 		ret = PTR_ERR(hibrst);
161 		dev_err_probe(dev, ret,
162 			      "failed to get hibernation reset signal\n");
163 		goto err;
164 	}
165 
166 	apbrst = devm_reset_control_get_exclusive(dev, "usb_apbrst");
167 	if (IS_ERR(apbrst)) {
168 		ret = PTR_ERR(apbrst);
169 		dev_err_probe(dev, ret,
170 			      "failed to get APB reset signal\n");
171 		goto err;
172 	}
173 
174 	ret = reset_control_assert(crst);
175 	if (ret < 0) {
176 		dev_err(dev, "Failed to assert core reset\n");
177 		goto err;
178 	}
179 
180 	ret = reset_control_assert(hibrst);
181 	if (ret < 0) {
182 		dev_err(dev, "Failed to assert hibernation reset\n");
183 		goto err;
184 	}
185 
186 	ret = reset_control_assert(apbrst);
187 	if (ret < 0) {
188 		dev_err(dev, "Failed to assert APB reset\n");
189 		goto err;
190 	}
191 
192 	ret = phy_init(priv_data->usb3_phy);
193 	if (ret < 0) {
194 		phy_exit(priv_data->usb3_phy);
195 		goto err;
196 	}
197 
198 	ret = reset_control_deassert(apbrst);
199 	if (ret < 0) {
200 		dev_err(dev, "Failed to release APB reset\n");
201 		goto err;
202 	}
203 
204 	/* Set PIPE Power Present signal in FPD Power Present Register*/
205 	writel(FPD_POWER_PRSNT_OPTION, priv_data->regs + XLNX_USB_FPD_POWER_PRSNT);
206 
207 	/* Set the PIPE Clock Select bit in FPD PIPE Clock register */
208 	writel(PIPE_CLK_SELECT, priv_data->regs + XLNX_USB_FPD_PIPE_CLK);
209 
210 	ret = reset_control_deassert(crst);
211 	if (ret < 0) {
212 		dev_err(dev, "Failed to release core reset\n");
213 		goto err;
214 	}
215 
216 	ret = reset_control_deassert(hibrst);
217 	if (ret < 0) {
218 		dev_err(dev, "Failed to release hibernation reset\n");
219 		goto err;
220 	}
221 
222 	ret = phy_power_on(priv_data->usb3_phy);
223 	if (ret < 0) {
224 		phy_exit(priv_data->usb3_phy);
225 		goto err;
226 	}
227 
228 skip_usb3_phy:
229 	/* ulpi reset via gpio-modepin or gpio-framework driver */
230 	reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
231 	if (IS_ERR(reset_gpio)) {
232 		return dev_err_probe(dev, PTR_ERR(reset_gpio),
233 				     "Failed to request reset GPIO\n");
234 	}
235 
236 	if (reset_gpio) {
237 		usleep_range(5000, 10000);
238 		gpiod_set_value_cansleep(reset_gpio, 0);
239 		usleep_range(5000, 10000);
240 	}
241 
242 	dwc3_xlnx_set_coherency(priv_data, XLNX_USB_TRAFFIC_ROUTE_CONFIG);
243 err:
244 	return ret;
245 }
246 
247 static const struct of_device_id dwc3_xlnx_of_match[] = {
248 	{
249 		.compatible = "xlnx,zynqmp-dwc3",
250 		.data = &dwc3_xlnx_init_zynqmp,
251 	},
252 	{
253 		.compatible = "xlnx,versal-dwc3",
254 		.data = &dwc3_xlnx_init_versal,
255 	},
256 	{ /* Sentinel */ }
257 };
258 MODULE_DEVICE_TABLE(of, dwc3_xlnx_of_match);
259 
dwc3_set_swnode(struct device * dev)260 static int dwc3_set_swnode(struct device *dev)
261 {
262 	struct device_node *np = dev->of_node, *dwc3_np;
263 	struct property_entry props[2];
264 	int prop_idx = 0, ret = 0;
265 
266 	dwc3_np = of_get_compatible_child(np, "snps,dwc3");
267 	if (!dwc3_np) {
268 		ret = -ENODEV;
269 		dev_err(dev, "failed to find dwc3 core child\n");
270 		return ret;
271 	}
272 
273 	memset(props, 0, sizeof(struct property_entry) * ARRAY_SIZE(props));
274 	if (of_dma_is_coherent(dwc3_np))
275 		props[prop_idx++] = PROPERTY_ENTRY_U16("snps,gsbuscfg0-reqinfo",
276 						       0xffff);
277 	of_node_put(dwc3_np);
278 
279 	if (prop_idx)
280 		ret = device_create_managed_software_node(dev, props, NULL);
281 
282 	return ret;
283 }
284 
dwc3_xlnx_probe(struct platform_device * pdev)285 static int dwc3_xlnx_probe(struct platform_device *pdev)
286 {
287 	struct dwc3_xlnx		*priv_data;
288 	struct device			*dev = &pdev->dev;
289 	struct device_node		*np = dev->of_node;
290 	const struct of_device_id	*match;
291 	void __iomem			*regs;
292 	int				ret;
293 
294 	priv_data = devm_kzalloc(dev, sizeof(*priv_data), GFP_KERNEL);
295 	if (!priv_data)
296 		return -ENOMEM;
297 
298 	regs = devm_platform_ioremap_resource(pdev, 0);
299 	if (IS_ERR(regs))
300 		return dev_err_probe(dev, PTR_ERR(regs), "failed to map registers\n");
301 
302 	match = of_match_node(dwc3_xlnx_of_match, pdev->dev.of_node);
303 
304 	priv_data->pltfm_init = match->data;
305 	priv_data->regs = regs;
306 	priv_data->dev = dev;
307 
308 	platform_set_drvdata(pdev, priv_data);
309 
310 	ret = devm_clk_bulk_get_all(priv_data->dev, &priv_data->clks);
311 	if (ret < 0)
312 		return ret;
313 
314 	priv_data->num_clocks = ret;
315 
316 	ret = clk_bulk_prepare_enable(priv_data->num_clocks, priv_data->clks);
317 	if (ret)
318 		return ret;
319 
320 	ret = priv_data->pltfm_init(priv_data);
321 	if (ret)
322 		goto err_clk_put;
323 
324 	ret = dwc3_set_swnode(dev);
325 	if (ret)
326 		goto err_clk_put;
327 
328 	ret = of_platform_populate(np, NULL, NULL, dev);
329 	if (ret)
330 		goto err_clk_put;
331 
332 	pm_runtime_set_active(dev);
333 	ret = devm_pm_runtime_enable(dev);
334 	if (ret < 0)
335 		goto err_pm_set_suspended;
336 
337 	pm_suspend_ignore_children(dev, false);
338 	ret = pm_runtime_resume_and_get(dev);
339 	if (ret < 0)
340 		goto err_pm_set_suspended;
341 
342 	return 0;
343 
344 err_pm_set_suspended:
345 	of_platform_depopulate(dev);
346 	pm_runtime_set_suspended(dev);
347 
348 err_clk_put:
349 	clk_bulk_disable_unprepare(priv_data->num_clocks, priv_data->clks);
350 
351 	return ret;
352 }
353 
dwc3_xlnx_remove(struct platform_device * pdev)354 static void dwc3_xlnx_remove(struct platform_device *pdev)
355 {
356 	struct dwc3_xlnx	*priv_data = platform_get_drvdata(pdev);
357 	struct device		*dev = &pdev->dev;
358 
359 	of_platform_depopulate(dev);
360 
361 	clk_bulk_disable_unprepare(priv_data->num_clocks, priv_data->clks);
362 	priv_data->num_clocks = 0;
363 
364 	pm_runtime_put_noidle(dev);
365 	pm_runtime_set_suspended(dev);
366 }
367 
dwc3_xlnx_runtime_suspend(struct device * dev)368 static int __maybe_unused dwc3_xlnx_runtime_suspend(struct device *dev)
369 {
370 	struct dwc3_xlnx *priv_data = dev_get_drvdata(dev);
371 
372 	clk_bulk_disable(priv_data->num_clocks, priv_data->clks);
373 
374 	return 0;
375 }
376 
dwc3_xlnx_runtime_resume(struct device * dev)377 static int __maybe_unused dwc3_xlnx_runtime_resume(struct device *dev)
378 {
379 	struct dwc3_xlnx *priv_data = dev_get_drvdata(dev);
380 
381 	return clk_bulk_enable(priv_data->num_clocks, priv_data->clks);
382 }
383 
dwc3_xlnx_runtime_idle(struct device * dev)384 static int __maybe_unused dwc3_xlnx_runtime_idle(struct device *dev)
385 {
386 	pm_runtime_mark_last_busy(dev);
387 	pm_runtime_autosuspend(dev);
388 
389 	return 0;
390 }
391 
dwc3_xlnx_suspend(struct device * dev)392 static int __maybe_unused dwc3_xlnx_suspend(struct device *dev)
393 {
394 	struct dwc3_xlnx *priv_data = dev_get_drvdata(dev);
395 
396 	phy_exit(priv_data->usb3_phy);
397 
398 	/* Disable the clocks */
399 	clk_bulk_disable(priv_data->num_clocks, priv_data->clks);
400 
401 	return 0;
402 }
403 
dwc3_xlnx_resume(struct device * dev)404 static int __maybe_unused dwc3_xlnx_resume(struct device *dev)
405 {
406 	struct dwc3_xlnx *priv_data = dev_get_drvdata(dev);
407 	int ret;
408 
409 	ret = clk_bulk_enable(priv_data->num_clocks, priv_data->clks);
410 	if (ret)
411 		return ret;
412 
413 	ret = phy_init(priv_data->usb3_phy);
414 	if (ret < 0)
415 		return ret;
416 
417 	ret = phy_power_on(priv_data->usb3_phy);
418 	if (ret < 0) {
419 		phy_exit(priv_data->usb3_phy);
420 		return ret;
421 	}
422 
423 	return 0;
424 }
425 
426 static const struct dev_pm_ops dwc3_xlnx_dev_pm_ops = {
427 	SET_SYSTEM_SLEEP_PM_OPS(dwc3_xlnx_suspend, dwc3_xlnx_resume)
428 	SET_RUNTIME_PM_OPS(dwc3_xlnx_runtime_suspend,
429 			   dwc3_xlnx_runtime_resume, dwc3_xlnx_runtime_idle)
430 };
431 
432 static struct platform_driver dwc3_xlnx_driver = {
433 	.probe		= dwc3_xlnx_probe,
434 	.remove		= dwc3_xlnx_remove,
435 	.shutdown	= dwc3_xlnx_remove,
436 	.driver		= {
437 		.name		= "dwc3-xilinx",
438 		.of_match_table	= dwc3_xlnx_of_match,
439 		.pm		= &dwc3_xlnx_dev_pm_ops,
440 	},
441 };
442 
443 module_platform_driver(dwc3_xlnx_driver);
444 
445 MODULE_LICENSE("GPL v2");
446 MODULE_DESCRIPTION("Xilinx DWC3 controller specific glue driver");
447 MODULE_AUTHOR("Manish Narani <manish.narani@xilinx.com>");
448 MODULE_AUTHOR("Anurag Kumar Vulisha <anurag.kumar.vulisha@xilinx.com>");
449