1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2016-2018 Broadcom
4 */
5
6#include <linux/delay.h>
7#include <linux/io.h>
8#include <linux/iopoll.h>
9#include <linux/module.h>
10#include <linux/of.h>
11#include <linux/phy/phy.h>
12#include <linux/platform_device.h>
13
14enum bcm_usb_phy_version {
15	BCM_SR_USB_COMBO_PHY,
16	BCM_SR_USB_HS_PHY,
17};
18
19enum bcm_usb_phy_reg {
20	PLL_CTRL,
21	PHY_CTRL,
22	PHY_PLL_CTRL,
23};
24
25/* USB PHY registers */
26
27static const u8 bcm_usb_combo_phy_ss[] = {
28	[PLL_CTRL]		= 0x18,
29	[PHY_CTRL]		= 0x14,
30};
31
32static const u8 bcm_usb_combo_phy_hs[] = {
33	[PLL_CTRL]	= 0x0c,
34	[PHY_CTRL]	= 0x10,
35};
36
37static const u8 bcm_usb_hs_phy[] = {
38	[PLL_CTRL]	= 0x8,
39	[PHY_CTRL]	= 0xc,
40};
41
42enum pll_ctrl_bits {
43	PLL_RESETB,
44	SSPLL_SUSPEND_EN,
45	PLL_SEQ_START,
46	PLL_LOCK,
47};
48
49static const u8 u3pll_ctrl[] = {
50	[PLL_RESETB]		= 0,
51	[SSPLL_SUSPEND_EN]	= 1,
52	[PLL_SEQ_START]		= 2,
53	[PLL_LOCK]		= 3,
54};
55
56#define HSPLL_PDIV_MASK		0xF
57#define HSPLL_PDIV_VAL		0x1
58
59static const u8 u2pll_ctrl[] = {
60	[PLL_RESETB]	= 5,
61	[PLL_LOCK]	= 6,
62};
63
64enum bcm_usb_phy_ctrl_bits {
65	CORERDY,
66	PHY_RESETB,
67	PHY_PCTL,
68};
69
70#define PHY_PCTL_MASK	0xffff
71#define SSPHY_PCTL_VAL	0x0006
72
73static const u8 u3phy_ctrl[] = {
74	[PHY_RESETB]	= 1,
75	[PHY_PCTL]	= 2,
76};
77
78static const u8 u2phy_ctrl[] = {
79	[CORERDY]		= 0,
80	[PHY_RESETB]		= 5,
81	[PHY_PCTL]		= 6,
82};
83
84struct bcm_usb_phy_cfg {
85	uint32_t type;
86	uint32_t version;
87	void __iomem *regs;
88	struct phy *phy;
89	const u8 *offset;
90};
91
92#define PLL_LOCK_RETRY_COUNT	1000
93
94enum bcm_usb_phy_type {
95	USB_HS_PHY,
96	USB_SS_PHY,
97};
98
99#define NUM_BCM_SR_USB_COMBO_PHYS	2
100
101static inline void bcm_usb_reg32_clrbits(void __iomem *addr, uint32_t clear)
102{
103	writel(readl(addr) & ~clear, addr);
104}
105
106static inline void bcm_usb_reg32_setbits(void __iomem *addr, uint32_t set)
107{
108	writel(readl(addr) | set, addr);
109}
110
111static int bcm_usb_pll_lock_check(void __iomem *addr, u32 bit)
112{
113	u32 data;
114	int ret;
115
116	ret = readl_poll_timeout_atomic(addr, data, (data & bit), 1,
117					PLL_LOCK_RETRY_COUNT);
118	if (ret)
119		pr_err("%s: FAIL\n", __func__);
120
121	return ret;
122}
123
124static int bcm_usb_ss_phy_init(struct bcm_usb_phy_cfg *phy_cfg)
125{
126	int ret = 0;
127	void __iomem *regs = phy_cfg->regs;
128	const u8 *offset;
129	u32 rd_data;
130
131	offset = phy_cfg->offset;
132
133	/* Set pctl with mode and soft reset */
134	rd_data = readl(regs + offset[PHY_CTRL]);
135	rd_data &= ~(PHY_PCTL_MASK << u3phy_ctrl[PHY_PCTL]);
136	rd_data |= (SSPHY_PCTL_VAL << u3phy_ctrl[PHY_PCTL]);
137	writel(rd_data, regs + offset[PHY_CTRL]);
138
139	bcm_usb_reg32_clrbits(regs + offset[PLL_CTRL],
140			      BIT(u3pll_ctrl[SSPLL_SUSPEND_EN]));
141	bcm_usb_reg32_setbits(regs + offset[PLL_CTRL],
142			      BIT(u3pll_ctrl[PLL_SEQ_START]));
143	bcm_usb_reg32_setbits(regs + offset[PLL_CTRL],
144			      BIT(u3pll_ctrl[PLL_RESETB]));
145
146	/* Maximum timeout for PLL reset done */
147	msleep(30);
148
149	ret = bcm_usb_pll_lock_check(regs + offset[PLL_CTRL],
150				     BIT(u3pll_ctrl[PLL_LOCK]));
151
152	return ret;
153}
154
155static int bcm_usb_hs_phy_init(struct bcm_usb_phy_cfg *phy_cfg)
156{
157	int ret = 0;
158	void __iomem *regs = phy_cfg->regs;
159	const u8 *offset;
160
161	offset = phy_cfg->offset;
162
163	bcm_usb_reg32_clrbits(regs + offset[PLL_CTRL],
164			      BIT(u2pll_ctrl[PLL_RESETB]));
165	bcm_usb_reg32_setbits(regs + offset[PLL_CTRL],
166			      BIT(u2pll_ctrl[PLL_RESETB]));
167
168	ret = bcm_usb_pll_lock_check(regs + offset[PLL_CTRL],
169				     BIT(u2pll_ctrl[PLL_LOCK]));
170
171	return ret;
172}
173
174static int bcm_usb_phy_reset(struct phy *phy)
175{
176	struct bcm_usb_phy_cfg *phy_cfg = phy_get_drvdata(phy);
177	void __iomem *regs = phy_cfg->regs;
178	const u8 *offset;
179
180	offset = phy_cfg->offset;
181
182	if (phy_cfg->type == USB_HS_PHY) {
183		bcm_usb_reg32_clrbits(regs + offset[PHY_CTRL],
184				      BIT(u2phy_ctrl[CORERDY]));
185		bcm_usb_reg32_setbits(regs + offset[PHY_CTRL],
186				      BIT(u2phy_ctrl[CORERDY]));
187	}
188
189	return 0;
190}
191
192static int bcm_usb_phy_init(struct phy *phy)
193{
194	struct bcm_usb_phy_cfg *phy_cfg = phy_get_drvdata(phy);
195	int ret = -EINVAL;
196
197	if (phy_cfg->type == USB_SS_PHY)
198		ret = bcm_usb_ss_phy_init(phy_cfg);
199	else if (phy_cfg->type == USB_HS_PHY)
200		ret = bcm_usb_hs_phy_init(phy_cfg);
201
202	return ret;
203}
204
205static const struct phy_ops sr_phy_ops = {
206	.init		= bcm_usb_phy_init,
207	.reset		= bcm_usb_phy_reset,
208	.owner		= THIS_MODULE,
209};
210
211static struct phy *bcm_usb_phy_xlate(struct device *dev,
212				     const struct of_phandle_args *args)
213{
214	struct bcm_usb_phy_cfg *phy_cfg;
215	int phy_idx;
216
217	phy_cfg = dev_get_drvdata(dev);
218	if (!phy_cfg)
219		return ERR_PTR(-EINVAL);
220
221	if (phy_cfg->version == BCM_SR_USB_COMBO_PHY) {
222		phy_idx = args->args[0];
223
224		if (WARN_ON(phy_idx > 1))
225			return ERR_PTR(-ENODEV);
226
227		return phy_cfg[phy_idx].phy;
228	} else
229		return phy_cfg->phy;
230}
231
232static int bcm_usb_phy_create(struct device *dev, struct device_node *node,
233			      void __iomem *regs, uint32_t version)
234{
235	struct bcm_usb_phy_cfg *phy_cfg;
236	int idx;
237
238	if (version == BCM_SR_USB_COMBO_PHY) {
239		phy_cfg = devm_kzalloc(dev, NUM_BCM_SR_USB_COMBO_PHYS *
240				       sizeof(struct bcm_usb_phy_cfg),
241				       GFP_KERNEL);
242		if (!phy_cfg)
243			return -ENOMEM;
244
245		for (idx = 0; idx < NUM_BCM_SR_USB_COMBO_PHYS; idx++) {
246			phy_cfg[idx].regs = regs;
247			phy_cfg[idx].version = version;
248			if (idx == 0) {
249				phy_cfg[idx].offset = bcm_usb_combo_phy_hs;
250				phy_cfg[idx].type = USB_HS_PHY;
251			} else {
252				phy_cfg[idx].offset = bcm_usb_combo_phy_ss;
253				phy_cfg[idx].type = USB_SS_PHY;
254			}
255			phy_cfg[idx].phy = devm_phy_create(dev, node,
256							   &sr_phy_ops);
257			if (IS_ERR(phy_cfg[idx].phy))
258				return PTR_ERR(phy_cfg[idx].phy);
259
260			phy_set_drvdata(phy_cfg[idx].phy, &phy_cfg[idx]);
261		}
262	} else if (version == BCM_SR_USB_HS_PHY) {
263		phy_cfg = devm_kzalloc(dev, sizeof(struct bcm_usb_phy_cfg),
264				       GFP_KERNEL);
265		if (!phy_cfg)
266			return -ENOMEM;
267
268		phy_cfg->regs = regs;
269		phy_cfg->version = version;
270		phy_cfg->offset = bcm_usb_hs_phy;
271		phy_cfg->type = USB_HS_PHY;
272		phy_cfg->phy = devm_phy_create(dev, node, &sr_phy_ops);
273		if (IS_ERR(phy_cfg->phy))
274			return PTR_ERR(phy_cfg->phy);
275
276		phy_set_drvdata(phy_cfg->phy, phy_cfg);
277	} else
278		return -ENODEV;
279
280	dev_set_drvdata(dev, phy_cfg);
281
282	return 0;
283}
284
285static const struct of_device_id bcm_usb_phy_of_match[] = {
286	{
287		.compatible = "brcm,sr-usb-combo-phy",
288		.data = (void *)BCM_SR_USB_COMBO_PHY,
289	},
290	{
291		.compatible = "brcm,sr-usb-hs-phy",
292		.data = (void *)BCM_SR_USB_HS_PHY,
293	},
294	{ /* sentinel */ },
295};
296MODULE_DEVICE_TABLE(of, bcm_usb_phy_of_match);
297
298static int bcm_usb_phy_probe(struct platform_device *pdev)
299{
300	struct device *dev = &pdev->dev;
301	struct device_node *dn = dev->of_node;
302	const struct of_device_id *of_id;
303	void __iomem *regs;
304	int ret;
305	enum bcm_usb_phy_version version;
306	struct phy_provider *phy_provider;
307
308	regs = devm_platform_ioremap_resource(pdev, 0);
309	if (IS_ERR(regs))
310		return PTR_ERR(regs);
311
312	of_id = of_match_node(bcm_usb_phy_of_match, dn);
313	if (of_id)
314		version = (uintptr_t)of_id->data;
315	else
316		return -ENODEV;
317
318	ret = bcm_usb_phy_create(dev, dn, regs, version);
319	if (ret)
320		return ret;
321
322	phy_provider = devm_of_phy_provider_register(dev, bcm_usb_phy_xlate);
323
324	return PTR_ERR_OR_ZERO(phy_provider);
325}
326
327static struct platform_driver bcm_usb_phy_driver = {
328	.driver = {
329		.name = "phy-bcm-sr-usb",
330		.of_match_table = bcm_usb_phy_of_match,
331	},
332	.probe = bcm_usb_phy_probe,
333};
334module_platform_driver(bcm_usb_phy_driver);
335
336MODULE_AUTHOR("Broadcom");
337MODULE_DESCRIPTION("Broadcom stingray USB Phy driver");
338MODULE_LICENSE("GPL v2");
339