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#define XLNX_USB_FPD_PIPE_CLK			0x7c
36#define PIPE_CLK_DESELECT			1
37#define PIPE_CLK_SELECT				0
38#define XLNX_USB_FPD_POWER_PRSNT		0x80
39#define FPD_POWER_PRSNT_OPTION			BIT(0)
40
41struct dwc3_xlnx {
42	int				num_clocks;
43	struct clk_bulk_data		*clks;
44	struct device			*dev;
45	void __iomem			*regs;
46	int				(*pltfm_init)(struct dwc3_xlnx *data);
47	struct phy			*usb3_phy;
48};
49
50static void dwc3_xlnx_mask_phy_rst(struct dwc3_xlnx *priv_data, bool mask)
51{
52	u32 reg;
53
54	/*
55	 * Enable or disable ULPI PHY reset from USB Controller.
56	 * This does not actually reset the phy, but just controls
57	 * whether USB controller can or cannot reset ULPI PHY.
58	 */
59	reg = readl(priv_data->regs + XLNX_USB_PHY_RST_EN);
60
61	if (mask)
62		reg &= ~XLNX_PHY_RST_MASK;
63	else
64		reg |= XLNX_PHY_RST_MASK;
65
66	writel(reg, priv_data->regs + XLNX_USB_PHY_RST_EN);
67}
68
69static int dwc3_xlnx_init_versal(struct dwc3_xlnx *priv_data)
70{
71	struct device		*dev = priv_data->dev;
72	struct reset_control	*crst;
73	int			ret;
74
75	crst = devm_reset_control_get_exclusive(dev, NULL);
76	if (IS_ERR(crst))
77		return dev_err_probe(dev, PTR_ERR(crst), "failed to get reset signal\n");
78
79	dwc3_xlnx_mask_phy_rst(priv_data, false);
80
81	/* Assert and De-assert reset */
82	ret = reset_control_assert(crst);
83	if (ret < 0) {
84		dev_err_probe(dev, ret, "failed to assert Reset\n");
85		return ret;
86	}
87
88	ret = reset_control_deassert(crst);
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
99static 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		goto skip_usb3_phy;
126
127	crst = devm_reset_control_get_exclusive(dev, "usb_crst");
128	if (IS_ERR(crst)) {
129		ret = PTR_ERR(crst);
130		dev_err_probe(dev, ret,
131			      "failed to get core reset signal\n");
132		goto err;
133	}
134
135	hibrst = devm_reset_control_get_exclusive(dev, "usb_hibrst");
136	if (IS_ERR(hibrst)) {
137		ret = PTR_ERR(hibrst);
138		dev_err_probe(dev, ret,
139			      "failed to get hibernation reset signal\n");
140		goto err;
141	}
142
143	apbrst = devm_reset_control_get_exclusive(dev, "usb_apbrst");
144	if (IS_ERR(apbrst)) {
145		ret = PTR_ERR(apbrst);
146		dev_err_probe(dev, ret,
147			      "failed to get APB reset signal\n");
148		goto err;
149	}
150
151	ret = reset_control_assert(crst);
152	if (ret < 0) {
153		dev_err(dev, "Failed to assert core reset\n");
154		goto err;
155	}
156
157	ret = reset_control_assert(hibrst);
158	if (ret < 0) {
159		dev_err(dev, "Failed to assert hibernation reset\n");
160		goto err;
161	}
162
163	ret = reset_control_assert(apbrst);
164	if (ret < 0) {
165		dev_err(dev, "Failed to assert APB reset\n");
166		goto err;
167	}
168
169	ret = phy_init(priv_data->usb3_phy);
170	if (ret < 0) {
171		phy_exit(priv_data->usb3_phy);
172		goto err;
173	}
174
175	ret = reset_control_deassert(apbrst);
176	if (ret < 0) {
177		dev_err(dev, "Failed to release APB reset\n");
178		goto err;
179	}
180
181	/* Set PIPE Power Present signal in FPD Power Present Register*/
182	writel(FPD_POWER_PRSNT_OPTION, priv_data->regs + XLNX_USB_FPD_POWER_PRSNT);
183
184	/* Set the PIPE Clock Select bit in FPD PIPE Clock register */
185	writel(PIPE_CLK_SELECT, priv_data->regs + XLNX_USB_FPD_PIPE_CLK);
186
187	ret = reset_control_deassert(crst);
188	if (ret < 0) {
189		dev_err(dev, "Failed to release core reset\n");
190		goto err;
191	}
192
193	ret = reset_control_deassert(hibrst);
194	if (ret < 0) {
195		dev_err(dev, "Failed to release hibernation reset\n");
196		goto err;
197	}
198
199	ret = phy_power_on(priv_data->usb3_phy);
200	if (ret < 0) {
201		phy_exit(priv_data->usb3_phy);
202		goto err;
203	}
204
205skip_usb3_phy:
206	/* ulpi reset via gpio-modepin or gpio-framework driver */
207	reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
208	if (IS_ERR(reset_gpio)) {
209		return dev_err_probe(dev, PTR_ERR(reset_gpio),
210				     "Failed to request reset GPIO\n");
211	}
212
213	if (reset_gpio) {
214		/* Toggle ulpi to reset the phy. */
215		gpiod_set_value_cansleep(reset_gpio, 1);
216		usleep_range(5000, 10000);
217		gpiod_set_value_cansleep(reset_gpio, 0);
218		usleep_range(5000, 10000);
219	}
220
221	/*
222	 * This routes the USB DMA traffic to go through FPD path instead
223	 * of reaching DDR directly. This traffic routing is needed to
224	 * make SMMU and CCI work with USB DMA.
225	 */
226	if (of_dma_is_coherent(dev->of_node) || device_iommu_mapped(dev)) {
227		reg = readl(priv_data->regs + XLNX_USB_TRAFFIC_ROUTE_CONFIG);
228		reg |= XLNX_USB_TRAFFIC_ROUTE_FPD;
229		writel(reg, priv_data->regs + XLNX_USB_TRAFFIC_ROUTE_CONFIG);
230	}
231
232err:
233	return ret;
234}
235
236static const struct of_device_id dwc3_xlnx_of_match[] = {
237	{
238		.compatible = "xlnx,zynqmp-dwc3",
239		.data = &dwc3_xlnx_init_zynqmp,
240	},
241	{
242		.compatible = "xlnx,versal-dwc3",
243		.data = &dwc3_xlnx_init_versal,
244	},
245	{ /* Sentinel */ }
246};
247MODULE_DEVICE_TABLE(of, dwc3_xlnx_of_match);
248
249static int dwc3_xlnx_probe(struct platform_device *pdev)
250{
251	struct dwc3_xlnx		*priv_data;
252	struct device			*dev = &pdev->dev;
253	struct device_node		*np = dev->of_node;
254	const struct of_device_id	*match;
255	void __iomem			*regs;
256	int				ret;
257
258	priv_data = devm_kzalloc(dev, sizeof(*priv_data), GFP_KERNEL);
259	if (!priv_data)
260		return -ENOMEM;
261
262	regs = devm_platform_ioremap_resource(pdev, 0);
263	if (IS_ERR(regs)) {
264		ret = PTR_ERR(regs);
265		dev_err_probe(dev, ret, "failed to map registers\n");
266		return ret;
267	}
268
269	match = of_match_node(dwc3_xlnx_of_match, pdev->dev.of_node);
270
271	priv_data->pltfm_init = match->data;
272	priv_data->regs = regs;
273	priv_data->dev = dev;
274
275	platform_set_drvdata(pdev, priv_data);
276
277	ret = devm_clk_bulk_get_all(priv_data->dev, &priv_data->clks);
278	if (ret < 0)
279		return ret;
280
281	priv_data->num_clocks = ret;
282
283	ret = clk_bulk_prepare_enable(priv_data->num_clocks, priv_data->clks);
284	if (ret)
285		return ret;
286
287	ret = priv_data->pltfm_init(priv_data);
288	if (ret)
289		goto err_clk_put;
290
291	ret = of_platform_populate(np, NULL, NULL, dev);
292	if (ret)
293		goto err_clk_put;
294
295	pm_runtime_set_active(dev);
296	ret = devm_pm_runtime_enable(dev);
297	if (ret < 0)
298		goto err_pm_set_suspended;
299
300	pm_suspend_ignore_children(dev, false);
301	return pm_runtime_resume_and_get(dev);
302
303err_pm_set_suspended:
304	pm_runtime_set_suspended(dev);
305
306err_clk_put:
307	clk_bulk_disable_unprepare(priv_data->num_clocks, priv_data->clks);
308
309	return ret;
310}
311
312static void dwc3_xlnx_remove(struct platform_device *pdev)
313{
314	struct dwc3_xlnx	*priv_data = platform_get_drvdata(pdev);
315	struct device		*dev = &pdev->dev;
316
317	of_platform_depopulate(dev);
318
319	clk_bulk_disable_unprepare(priv_data->num_clocks, priv_data->clks);
320	priv_data->num_clocks = 0;
321
322	pm_runtime_put_noidle(dev);
323	pm_runtime_set_suspended(dev);
324}
325
326static 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
335static 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
342static 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
350static 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
362static 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
384static 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
390static 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
400module_platform_driver(dwc3_xlnx_driver);
401
402MODULE_LICENSE("GPL v2");
403MODULE_DESCRIPTION("Xilinx DWC3 controller specific glue driver");
404MODULE_AUTHOR("Manish Narani <manish.narani@xilinx.com>");
405MODULE_AUTHOR("Anurag Kumar Vulisha <anurag.kumar.vulisha@xilinx.com>");
406