1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Broadcom Northstar USB 3.0 PHY Driver
4 *
5 * Copyright (C) 2016 Rafał Miłecki <rafal@milecki.pl>
6 * Copyright (C) 2016 Broadcom
7 *
8 * All magic values used for initialization (and related comments) were obtained
9 * from Broadcom's SDK:
10 * Copyright (c) Broadcom Corp, 2012
11 */
12
13#include <linux/bcma/bcma.h>
14#include <linux/delay.h>
15#include <linux/err.h>
16#include <linux/iopoll.h>
17#include <linux/mdio.h>
18#include <linux/module.h>
19#include <linux/of_address.h>
20#include <linux/of_platform.h>
21#include <linux/platform_device.h>
22#include <linux/phy/phy.h>
23#include <linux/slab.h>
24
25#define BCM_NS_USB3_MII_MNG_TIMEOUT_US	1000	/* usecs */
26
27#define BCM_NS_USB3_PHY_BASE_ADDR_REG	0x1f
28#define BCM_NS_USB3_PHY_PLL30_BLOCK	0x8000
29#define BCM_NS_USB3_PHY_TX_PMD_BLOCK	0x8040
30#define BCM_NS_USB3_PHY_PIPE_BLOCK	0x8060
31
32/* Registers of PLL30 block */
33#define BCM_NS_USB3_PLL_CONTROL		0x01
34#define BCM_NS_USB3_PLLA_CONTROL0	0x0a
35#define BCM_NS_USB3_PLLA_CONTROL1	0x0b
36
37/* Registers of TX PMD block */
38#define BCM_NS_USB3_TX_PMD_CONTROL1	0x01
39
40/* Registers of PIPE block */
41#define BCM_NS_USB3_LFPS_CMP		0x02
42#define BCM_NS_USB3_LFPS_DEGLITCH	0x03
43
44enum bcm_ns_family {
45	BCM_NS_UNKNOWN,
46	BCM_NS_AX,
47	BCM_NS_BX,
48};
49
50struct bcm_ns_usb3 {
51	struct device *dev;
52	enum bcm_ns_family family;
53	void __iomem *dmp;
54	void __iomem *ccb_mii;
55	struct mdio_device *mdiodev;
56	struct phy *phy;
57
58	int (*phy_write)(struct bcm_ns_usb3 *usb3, u16 reg, u16 value);
59};
60
61static const struct of_device_id bcm_ns_usb3_id_table[] = {
62	{
63		.compatible = "brcm,ns-ax-usb3-phy",
64		.data = (int *)BCM_NS_AX,
65	},
66	{
67		.compatible = "brcm,ns-bx-usb3-phy",
68		.data = (int *)BCM_NS_BX,
69	},
70	{},
71};
72MODULE_DEVICE_TABLE(of, bcm_ns_usb3_id_table);
73
74static int bcm_ns_usb3_mdio_phy_write(struct bcm_ns_usb3 *usb3, u16 reg,
75				      u16 value)
76{
77	return usb3->phy_write(usb3, reg, value);
78}
79
80static int bcm_ns_usb3_phy_init_ns_bx(struct bcm_ns_usb3 *usb3)
81{
82	int err;
83
84	/* USB3 PLL Block */
85	err = bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_PHY_BASE_ADDR_REG,
86					 BCM_NS_USB3_PHY_PLL30_BLOCK);
87	if (err < 0)
88		return err;
89
90	/* Assert Ana_Pllseq start */
91	bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_PLL_CONTROL, 0x1000);
92
93	/* Assert CML Divider ratio to 26 */
94	bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_PLLA_CONTROL0, 0x6400);
95
96	/* Asserting PLL Reset */
97	bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_PLLA_CONTROL1, 0xc000);
98
99	/* Deaaserting PLL Reset */
100	bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_PLLA_CONTROL1, 0x8000);
101
102	/* Deasserting USB3 system reset */
103	writel(0, usb3->dmp + BCMA_RESET_CTL);
104
105	/* PLL frequency monitor enable */
106	bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_PLL_CONTROL, 0x9000);
107
108	/* PIPE Block */
109	bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_PHY_BASE_ADDR_REG,
110				   BCM_NS_USB3_PHY_PIPE_BLOCK);
111
112	/* CMPMAX & CMPMINTH setting */
113	bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_LFPS_CMP, 0xf30d);
114
115	/* DEGLITCH MIN & MAX setting */
116	bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_LFPS_DEGLITCH, 0x6302);
117
118	/* TXPMD block */
119	bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_PHY_BASE_ADDR_REG,
120				   BCM_NS_USB3_PHY_TX_PMD_BLOCK);
121
122	/* Enabling SSC */
123	bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_TX_PMD_CONTROL1, 0x1003);
124
125	return 0;
126}
127
128static int bcm_ns_usb3_phy_init_ns_ax(struct bcm_ns_usb3 *usb3)
129{
130	int err;
131
132	/* PLL30 block */
133	err = bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_PHY_BASE_ADDR_REG,
134					 BCM_NS_USB3_PHY_PLL30_BLOCK);
135	if (err < 0)
136		return err;
137
138	bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_PLLA_CONTROL0, 0x6400);
139
140	bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_PHY_BASE_ADDR_REG, 0x80e0);
141
142	bcm_ns_usb3_mdio_phy_write(usb3, 0x02, 0x009c);
143
144	/* Enable SSC */
145	bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_PHY_BASE_ADDR_REG,
146				   BCM_NS_USB3_PHY_TX_PMD_BLOCK);
147
148	bcm_ns_usb3_mdio_phy_write(usb3, 0x02, 0x21d3);
149
150	bcm_ns_usb3_mdio_phy_write(usb3, BCM_NS_USB3_TX_PMD_CONTROL1, 0x1003);
151
152	/* Deasserting USB3 system reset */
153	writel(0, usb3->dmp + BCMA_RESET_CTL);
154
155	return 0;
156}
157
158static int bcm_ns_usb3_phy_init(struct phy *phy)
159{
160	struct bcm_ns_usb3 *usb3 = phy_get_drvdata(phy);
161	int err;
162
163	/* Perform USB3 system soft reset */
164	writel(BCMA_RESET_CTL_RESET, usb3->dmp + BCMA_RESET_CTL);
165
166	switch (usb3->family) {
167	case BCM_NS_AX:
168		err = bcm_ns_usb3_phy_init_ns_ax(usb3);
169		break;
170	case BCM_NS_BX:
171		err = bcm_ns_usb3_phy_init_ns_bx(usb3);
172		break;
173	default:
174		WARN_ON(1);
175		err = -ENOTSUPP;
176	}
177
178	return err;
179}
180
181static const struct phy_ops ops = {
182	.init		= bcm_ns_usb3_phy_init,
183	.owner		= THIS_MODULE,
184};
185
186/**************************************************
187 * MDIO driver code
188 **************************************************/
189
190static int bcm_ns_usb3_mdiodev_phy_write(struct bcm_ns_usb3 *usb3, u16 reg,
191					 u16 value)
192{
193	struct mdio_device *mdiodev = usb3->mdiodev;
194
195	return mdiobus_write(mdiodev->bus, mdiodev->addr, reg, value);
196}
197
198static int bcm_ns_usb3_mdio_probe(struct mdio_device *mdiodev)
199{
200	struct device *dev = &mdiodev->dev;
201	const struct of_device_id *of_id;
202	struct phy_provider *phy_provider;
203	struct device_node *syscon_np;
204	struct bcm_ns_usb3 *usb3;
205	struct resource res;
206	int err;
207
208	usb3 = devm_kzalloc(dev, sizeof(*usb3), GFP_KERNEL);
209	if (!usb3)
210		return -ENOMEM;
211
212	usb3->dev = dev;
213	usb3->mdiodev = mdiodev;
214
215	of_id = of_match_device(bcm_ns_usb3_id_table, dev);
216	if (!of_id)
217		return -EINVAL;
218	usb3->family = (enum bcm_ns_family)of_id->data;
219
220	syscon_np = of_parse_phandle(dev->of_node, "usb3-dmp-syscon", 0);
221	err = of_address_to_resource(syscon_np, 0, &res);
222	of_node_put(syscon_np);
223	if (err)
224		return err;
225
226	usb3->dmp = devm_ioremap_resource(dev, &res);
227	if (IS_ERR(usb3->dmp)) {
228		dev_err(dev, "Failed to map DMP regs\n");
229		return PTR_ERR(usb3->dmp);
230	}
231
232	usb3->phy_write = bcm_ns_usb3_mdiodev_phy_write;
233
234	usb3->phy = devm_phy_create(dev, NULL, &ops);
235	if (IS_ERR(usb3->phy)) {
236		dev_err(dev, "Failed to create PHY\n");
237		return PTR_ERR(usb3->phy);
238	}
239
240	phy_set_drvdata(usb3->phy, usb3);
241
242	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
243
244	return PTR_ERR_OR_ZERO(phy_provider);
245}
246
247static struct mdio_driver bcm_ns_usb3_mdio_driver = {
248	.mdiodrv = {
249		.driver = {
250			.name = "bcm_ns_mdio_usb3",
251			.of_match_table = bcm_ns_usb3_id_table,
252		},
253	},
254	.probe = bcm_ns_usb3_mdio_probe,
255};
256
257/**************************************************
258 * Platform driver code
259 **************************************************/
260
261static int bcm_ns_usb3_wait_reg(struct bcm_ns_usb3 *usb3, void __iomem *addr,
262				u32 mask, u32 value, int usec)
263{
264	u32 val;
265	int ret;
266
267	ret = readl_poll_timeout_atomic(addr, val, ((val & mask) == value),
268					10, usec);
269	if (ret)
270		dev_err(usb3->dev, "Timeout waiting for register %p\n", addr);
271
272	return ret;
273}
274
275static inline int bcm_ns_usb3_mii_mng_wait_idle(struct bcm_ns_usb3 *usb3)
276{
277	return bcm_ns_usb3_wait_reg(usb3, usb3->ccb_mii + BCMA_CCB_MII_MNG_CTL,
278				    0x0100, 0x0000,
279				    BCM_NS_USB3_MII_MNG_TIMEOUT_US);
280}
281
282static int bcm_ns_usb3_platform_phy_write(struct bcm_ns_usb3 *usb3, u16 reg,
283					  u16 value)
284{
285	u32 tmp = 0;
286	int err;
287
288	err = bcm_ns_usb3_mii_mng_wait_idle(usb3);
289	if (err < 0) {
290		dev_err(usb3->dev, "Couldn't write 0x%08x value\n", value);
291		return err;
292	}
293
294	/* TODO: Use a proper MDIO bus layer */
295	tmp |= 0x58020000; /* Magic value for MDIO PHY write */
296	tmp |= reg << 18;
297	tmp |= value;
298	writel(tmp, usb3->ccb_mii + BCMA_CCB_MII_MNG_CMD_DATA);
299
300	return bcm_ns_usb3_mii_mng_wait_idle(usb3);
301}
302
303static int bcm_ns_usb3_probe(struct platform_device *pdev)
304{
305	struct device *dev = &pdev->dev;
306	const struct of_device_id *of_id;
307	struct bcm_ns_usb3 *usb3;
308	struct resource *res;
309	struct phy_provider *phy_provider;
310
311	usb3 = devm_kzalloc(dev, sizeof(*usb3), GFP_KERNEL);
312	if (!usb3)
313		return -ENOMEM;
314
315	usb3->dev = dev;
316
317	of_id = of_match_device(bcm_ns_usb3_id_table, dev);
318	if (!of_id)
319		return -EINVAL;
320	usb3->family = (enum bcm_ns_family)of_id->data;
321
322	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dmp");
323	usb3->dmp = devm_ioremap_resource(dev, res);
324	if (IS_ERR(usb3->dmp)) {
325		dev_err(dev, "Failed to map DMP regs\n");
326		return PTR_ERR(usb3->dmp);
327	}
328
329	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ccb-mii");
330	usb3->ccb_mii = devm_ioremap_resource(dev, res);
331	if (IS_ERR(usb3->ccb_mii)) {
332		dev_err(dev, "Failed to map ChipCommon B MII regs\n");
333		return PTR_ERR(usb3->ccb_mii);
334	}
335
336	/* Enable MDIO. Setting MDCDIV as 26  */
337	writel(0x0000009a, usb3->ccb_mii + BCMA_CCB_MII_MNG_CTL);
338
339	/* Wait for MDIO? */
340	udelay(2);
341
342	usb3->phy_write = bcm_ns_usb3_platform_phy_write;
343
344	usb3->phy = devm_phy_create(dev, NULL, &ops);
345	if (IS_ERR(usb3->phy)) {
346		dev_err(dev, "Failed to create PHY\n");
347		return PTR_ERR(usb3->phy);
348	}
349
350	phy_set_drvdata(usb3->phy, usb3);
351	platform_set_drvdata(pdev, usb3);
352
353	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
354	if (!IS_ERR(phy_provider))
355		dev_info(dev, "Registered Broadcom Northstar USB 3.0 PHY driver\n");
356
357	return PTR_ERR_OR_ZERO(phy_provider);
358}
359
360static struct platform_driver bcm_ns_usb3_driver = {
361	.probe		= bcm_ns_usb3_probe,
362	.driver = {
363		.name = "bcm_ns_usb3",
364		.of_match_table = bcm_ns_usb3_id_table,
365	},
366};
367
368static int __init bcm_ns_usb3_module_init(void)
369{
370	int err;
371
372	/*
373	 * For backward compatibility we register as MDIO and platform driver.
374	 * After getting MDIO binding commonly used (e.g. switching all DT files
375	 * to use it) we should deprecate the old binding and eventually drop
376	 * support for it.
377	 */
378
379	err = mdio_driver_register(&bcm_ns_usb3_mdio_driver);
380	if (err)
381		return err;
382
383	err = platform_driver_register(&bcm_ns_usb3_driver);
384	if (err)
385		mdio_driver_unregister(&bcm_ns_usb3_mdio_driver);
386
387	return err;
388}
389module_init(bcm_ns_usb3_module_init);
390
391static void __exit bcm_ns_usb3_module_exit(void)
392{
393	platform_driver_unregister(&bcm_ns_usb3_driver);
394	mdio_driver_unregister(&bcm_ns_usb3_mdio_driver);
395}
396module_exit(bcm_ns_usb3_module_exit)
397
398MODULE_LICENSE("GPL v2");
399