xref: /openbmc/linux/drivers/usb/dwc3/dwc3-xilinx.c (revision 77d62fcc)
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/of_platform.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/reset.h>
19 #include <linux/of_address.h>
20 #include <linux/delay.h>
21 #include <linux/firmware/xlnx-zynqmp.h>
22 #include <linux/io.h>
23 
24 #include <linux/phy/phy.h>
25 
26 /* USB phy reset mask register */
27 #define XLNX_USB_PHY_RST_EN			0x001C
28 #define XLNX_PHY_RST_MASK			0x1
29 
30 /* Xilinx USB 3.0 IP Register */
31 #define XLNX_USB_TRAFFIC_ROUTE_CONFIG		0x005C
32 #define XLNX_USB_TRAFFIC_ROUTE_FPD		0x1
33 
34 /* Versal USB Reset ID */
35 #define VERSAL_USB_RESET_ID			0xC104036
36 
37 #define XLNX_USB_FPD_PIPE_CLK			0x7c
38 #define PIPE_CLK_DESELECT			1
39 #define PIPE_CLK_SELECT				0
40 #define XLNX_USB_FPD_POWER_PRSNT		0x80
41 #define FPD_POWER_PRSNT_OPTION			BIT(0)
42 
43 struct dwc3_xlnx {
44 	int				num_clocks;
45 	struct clk_bulk_data		*clks;
46 	struct device			*dev;
47 	void __iomem			*regs;
48 	int				(*pltfm_init)(struct dwc3_xlnx *data);
49 };
50 
51 static void dwc3_xlnx_mask_phy_rst(struct dwc3_xlnx *priv_data, bool mask)
52 {
53 	u32 reg;
54 
55 	/*
56 	 * Enable or disable ULPI PHY reset from USB Controller.
57 	 * This does not actually reset the phy, but just controls
58 	 * whether USB controller can or cannot reset ULPI PHY.
59 	 */
60 	reg = readl(priv_data->regs + XLNX_USB_PHY_RST_EN);
61 
62 	if (mask)
63 		reg &= ~XLNX_PHY_RST_MASK;
64 	else
65 		reg |= XLNX_PHY_RST_MASK;
66 
67 	writel(reg, priv_data->regs + XLNX_USB_PHY_RST_EN);
68 }
69 
70 static int dwc3_xlnx_init_versal(struct dwc3_xlnx *priv_data)
71 {
72 	struct device		*dev = priv_data->dev;
73 	int			ret;
74 
75 	dwc3_xlnx_mask_phy_rst(priv_data, false);
76 
77 	/* Assert and De-assert reset */
78 	ret = zynqmp_pm_reset_assert(VERSAL_USB_RESET_ID,
79 				     PM_RESET_ACTION_ASSERT);
80 	if (ret < 0) {
81 		dev_err_probe(dev, ret, "failed to assert Reset\n");
82 		return ret;
83 	}
84 
85 	ret = zynqmp_pm_reset_assert(VERSAL_USB_RESET_ID,
86 				     PM_RESET_ACTION_RELEASE);
87 	if (ret < 0) {
88 		dev_err_probe(dev, ret, "failed to De-assert Reset\n");
89 		return ret;
90 	}
91 
92 	dwc3_xlnx_mask_phy_rst(priv_data, true);
93 
94 	return 0;
95 }
96 
97 static int dwc3_xlnx_init_zynqmp(struct dwc3_xlnx *priv_data)
98 {
99 	struct device		*dev = priv_data->dev;
100 	struct reset_control	*crst, *hibrst, *apbrst;
101 	struct phy		*usb3_phy;
102 	int			ret;
103 	u32			reg;
104 
105 	usb3_phy = devm_phy_optional_get(dev, "usb3-phy");
106 	if (IS_ERR(usb3_phy)) {
107 		ret = PTR_ERR(usb3_phy);
108 		dev_err_probe(dev, ret,
109 			      "failed to get USB3 PHY\n");
110 		goto err;
111 	}
112 
113 	/*
114 	 * The following core resets are not required unless a USB3 PHY
115 	 * is used, and the subsequent register settings are not required
116 	 * unless a core reset is performed (they should be set properly
117 	 * by the first-stage boot loader, but may be reverted by a core
118 	 * reset). They may also break the configuration if USB3 is actually
119 	 * in use but the usb3-phy entry is missing from the device tree.
120 	 * Therefore, skip these operations in this case.
121 	 */
122 	if (!usb3_phy)
123 		goto skip_usb3_phy;
124 
125 	crst = devm_reset_control_get_exclusive(dev, "usb_crst");
126 	if (IS_ERR(crst)) {
127 		ret = PTR_ERR(crst);
128 		dev_err_probe(dev, ret,
129 			      "failed to get core reset signal\n");
130 		goto err;
131 	}
132 
133 	hibrst = devm_reset_control_get_exclusive(dev, "usb_hibrst");
134 	if (IS_ERR(hibrst)) {
135 		ret = PTR_ERR(hibrst);
136 		dev_err_probe(dev, ret,
137 			      "failed to get hibernation reset signal\n");
138 		goto err;
139 	}
140 
141 	apbrst = devm_reset_control_get_exclusive(dev, "usb_apbrst");
142 	if (IS_ERR(apbrst)) {
143 		ret = PTR_ERR(apbrst);
144 		dev_err_probe(dev, ret,
145 			      "failed to get APB reset signal\n");
146 		goto err;
147 	}
148 
149 	ret = reset_control_assert(crst);
150 	if (ret < 0) {
151 		dev_err(dev, "Failed to assert core reset\n");
152 		goto err;
153 	}
154 
155 	ret = reset_control_assert(hibrst);
156 	if (ret < 0) {
157 		dev_err(dev, "Failed to assert hibernation reset\n");
158 		goto err;
159 	}
160 
161 	ret = reset_control_assert(apbrst);
162 	if (ret < 0) {
163 		dev_err(dev, "Failed to assert APB reset\n");
164 		goto err;
165 	}
166 
167 	ret = phy_init(usb3_phy);
168 	if (ret < 0) {
169 		phy_exit(usb3_phy);
170 		goto err;
171 	}
172 
173 	ret = reset_control_deassert(apbrst);
174 	if (ret < 0) {
175 		dev_err(dev, "Failed to release APB reset\n");
176 		goto err;
177 	}
178 
179 	/* Set PIPE Power Present signal in FPD Power Present Register*/
180 	writel(FPD_POWER_PRSNT_OPTION, priv_data->regs + XLNX_USB_FPD_POWER_PRSNT);
181 
182 	/* Set the PIPE Clock Select bit in FPD PIPE Clock register */
183 	writel(PIPE_CLK_SELECT, priv_data->regs + XLNX_USB_FPD_PIPE_CLK);
184 
185 	ret = reset_control_deassert(crst);
186 	if (ret < 0) {
187 		dev_err(dev, "Failed to release core reset\n");
188 		goto err;
189 	}
190 
191 	ret = reset_control_deassert(hibrst);
192 	if (ret < 0) {
193 		dev_err(dev, "Failed to release hibernation reset\n");
194 		goto err;
195 	}
196 
197 	ret = phy_power_on(usb3_phy);
198 	if (ret < 0) {
199 		phy_exit(usb3_phy);
200 		goto err;
201 	}
202 
203 skip_usb3_phy:
204 	/*
205 	 * This routes the USB DMA traffic to go through FPD path instead
206 	 * of reaching DDR directly. This traffic routing is needed to
207 	 * make SMMU and CCI work with USB DMA.
208 	 */
209 	if (of_dma_is_coherent(dev->of_node) || device_iommu_mapped(dev)) {
210 		reg = readl(priv_data->regs + XLNX_USB_TRAFFIC_ROUTE_CONFIG);
211 		reg |= XLNX_USB_TRAFFIC_ROUTE_FPD;
212 		writel(reg, priv_data->regs + XLNX_USB_TRAFFIC_ROUTE_CONFIG);
213 	}
214 
215 err:
216 	return ret;
217 }
218 
219 static const struct of_device_id dwc3_xlnx_of_match[] = {
220 	{
221 		.compatible = "xlnx,zynqmp-dwc3",
222 		.data = &dwc3_xlnx_init_zynqmp,
223 	},
224 	{
225 		.compatible = "xlnx,versal-dwc3",
226 		.data = &dwc3_xlnx_init_versal,
227 	},
228 	{ /* Sentinel */ }
229 };
230 MODULE_DEVICE_TABLE(of, dwc3_xlnx_of_match);
231 
232 static int dwc3_xlnx_probe(struct platform_device *pdev)
233 {
234 	struct dwc3_xlnx		*priv_data;
235 	struct device			*dev = &pdev->dev;
236 	struct device_node		*np = dev->of_node;
237 	const struct of_device_id	*match;
238 	void __iomem			*regs;
239 	int				ret;
240 
241 	priv_data = devm_kzalloc(dev, sizeof(*priv_data), GFP_KERNEL);
242 	if (!priv_data)
243 		return -ENOMEM;
244 
245 	regs = devm_platform_ioremap_resource(pdev, 0);
246 	if (IS_ERR(regs)) {
247 		ret = PTR_ERR(regs);
248 		dev_err_probe(dev, ret, "failed to map registers\n");
249 		return ret;
250 	}
251 
252 	match = of_match_node(dwc3_xlnx_of_match, pdev->dev.of_node);
253 
254 	priv_data->pltfm_init = match->data;
255 	priv_data->regs = regs;
256 	priv_data->dev = dev;
257 
258 	platform_set_drvdata(pdev, priv_data);
259 
260 	ret = devm_clk_bulk_get_all(priv_data->dev, &priv_data->clks);
261 	if (ret < 0)
262 		return ret;
263 
264 	priv_data->num_clocks = ret;
265 
266 	ret = clk_bulk_prepare_enable(priv_data->num_clocks, priv_data->clks);
267 	if (ret)
268 		return ret;
269 
270 	ret = priv_data->pltfm_init(priv_data);
271 	if (ret)
272 		goto err_clk_put;
273 
274 	ret = of_platform_populate(np, NULL, NULL, dev);
275 	if (ret)
276 		goto err_clk_put;
277 
278 	pm_runtime_set_active(dev);
279 	pm_runtime_enable(dev);
280 	pm_suspend_ignore_children(dev, false);
281 	pm_runtime_get_sync(dev);
282 
283 	return 0;
284 
285 err_clk_put:
286 	clk_bulk_disable_unprepare(priv_data->num_clocks, priv_data->clks);
287 
288 	return ret;
289 }
290 
291 static int dwc3_xlnx_remove(struct platform_device *pdev)
292 {
293 	struct dwc3_xlnx	*priv_data = platform_get_drvdata(pdev);
294 	struct device		*dev = &pdev->dev;
295 
296 	of_platform_depopulate(dev);
297 
298 	clk_bulk_disable_unprepare(priv_data->num_clocks, priv_data->clks);
299 	priv_data->num_clocks = 0;
300 
301 	pm_runtime_disable(dev);
302 	pm_runtime_put_noidle(dev);
303 	pm_runtime_set_suspended(dev);
304 
305 	return 0;
306 }
307 
308 static int __maybe_unused dwc3_xlnx_suspend_common(struct device *dev)
309 {
310 	struct dwc3_xlnx *priv_data = dev_get_drvdata(dev);
311 
312 	clk_bulk_disable(priv_data->num_clocks, priv_data->clks);
313 
314 	return 0;
315 }
316 
317 static int __maybe_unused dwc3_xlnx_resume_common(struct device *dev)
318 {
319 	struct dwc3_xlnx *priv_data = dev_get_drvdata(dev);
320 
321 	return clk_bulk_enable(priv_data->num_clocks, priv_data->clks);
322 }
323 
324 static int __maybe_unused dwc3_xlnx_runtime_idle(struct device *dev)
325 {
326 	pm_runtime_mark_last_busy(dev);
327 	pm_runtime_autosuspend(dev);
328 
329 	return 0;
330 }
331 
332 static UNIVERSAL_DEV_PM_OPS(dwc3_xlnx_dev_pm_ops, dwc3_xlnx_suspend_common,
333 			    dwc3_xlnx_resume_common, dwc3_xlnx_runtime_idle);
334 
335 static struct platform_driver dwc3_xlnx_driver = {
336 	.probe		= dwc3_xlnx_probe,
337 	.remove		= dwc3_xlnx_remove,
338 	.driver		= {
339 		.name		= "dwc3-xilinx",
340 		.of_match_table	= dwc3_xlnx_of_match,
341 		.pm		= &dwc3_xlnx_dev_pm_ops,
342 	},
343 };
344 
345 module_platform_driver(dwc3_xlnx_driver);
346 
347 MODULE_LICENSE("GPL v2");
348 MODULE_DESCRIPTION("Xilinx DWC3 controller specific glue driver");
349 MODULE_AUTHOR("Manish Narani <manish.narani@xilinx.com>");
350 MODULE_AUTHOR("Anurag Kumar Vulisha <anurag.kumar.vulisha@xilinx.com>");
351