1// SPDX-License-Identifier: GPL-2.0
2/* Renesas Ethernet SERDES device driver
3 *
4 * Copyright (C) 2022 Renesas Electronics Corporation
5 */
6
7#include <linux/delay.h>
8#include <linux/err.h>
9#include <linux/iopoll.h>
10#include <linux/kernel.h>
11#include <linux/of.h>
12#include <linux/phy.h>
13#include <linux/phy/phy.h>
14#include <linux/platform_device.h>
15#include <linux/reset.h>
16
17#define R8A779F0_ETH_SERDES_NUM			3
18#define R8A779F0_ETH_SERDES_OFFSET		0x0400
19#define R8A779F0_ETH_SERDES_BANK_SELECT		0x03fc
20#define R8A779F0_ETH_SERDES_TIMEOUT_US		100000
21#define R8A779F0_ETH_SERDES_NUM_RETRY_LINKUP	3
22
23struct r8a779f0_eth_serdes_drv_data;
24struct r8a779f0_eth_serdes_channel {
25	struct r8a779f0_eth_serdes_drv_data *dd;
26	struct phy *phy;
27	void __iomem *addr;
28	phy_interface_t phy_interface;
29	int speed;
30	int index;
31};
32
33struct r8a779f0_eth_serdes_drv_data {
34	void __iomem *addr;
35	struct platform_device *pdev;
36	struct reset_control *reset;
37	struct r8a779f0_eth_serdes_channel channel[R8A779F0_ETH_SERDES_NUM];
38	bool initialized;
39};
40
41/*
42 * The datasheet describes initialization procedure without any information
43 * about registers' name/bits. So, this is all black magic to initialize
44 * the hardware.
45 */
46static void r8a779f0_eth_serdes_write32(void __iomem *addr, u32 offs, u32 bank, u32 data)
47{
48	iowrite32(bank, addr + R8A779F0_ETH_SERDES_BANK_SELECT);
49	iowrite32(data, addr + offs);
50}
51
52static int
53r8a779f0_eth_serdes_reg_wait(struct r8a779f0_eth_serdes_channel *channel,
54			     u32 offs, u32 bank, u32 mask, u32 expected)
55{
56	int ret;
57	u32 val;
58
59	iowrite32(bank, channel->addr + R8A779F0_ETH_SERDES_BANK_SELECT);
60
61	ret = readl_poll_timeout_atomic(channel->addr + offs, val,
62					(val & mask) == expected,
63					1, R8A779F0_ETH_SERDES_TIMEOUT_US);
64	if (ret)
65		dev_dbg(&channel->phy->dev,
66			"%s: index %d, offs %x, bank %x, mask %x, expected %x\n",
67			 __func__, channel->index, offs, bank, mask, expected);
68
69	return ret;
70}
71
72static int
73r8a779f0_eth_serdes_common_init_ram(struct r8a779f0_eth_serdes_drv_data *dd)
74{
75	struct r8a779f0_eth_serdes_channel *channel;
76	int i, ret;
77
78	for (i = 0; i < R8A779F0_ETH_SERDES_NUM; i++) {
79		channel = &dd->channel[i];
80		ret = r8a779f0_eth_serdes_reg_wait(channel, 0x026c, 0x180, BIT(0), 0x01);
81		if (ret)
82			return ret;
83	}
84
85	r8a779f0_eth_serdes_write32(dd->addr, 0x026c, 0x180, 0x03);
86
87	return ret;
88}
89
90static int
91r8a779f0_eth_serdes_common_setting(struct r8a779f0_eth_serdes_channel *channel)
92{
93	struct r8a779f0_eth_serdes_drv_data *dd = channel->dd;
94
95	switch (channel->phy_interface) {
96	case PHY_INTERFACE_MODE_SGMII:
97		r8a779f0_eth_serdes_write32(dd->addr, 0x0244, 0x180, 0x0097);
98		r8a779f0_eth_serdes_write32(dd->addr, 0x01d0, 0x180, 0x0060);
99		r8a779f0_eth_serdes_write32(dd->addr, 0x01d8, 0x180, 0x2200);
100		r8a779f0_eth_serdes_write32(dd->addr, 0x01d4, 0x180, 0x0000);
101		r8a779f0_eth_serdes_write32(dd->addr, 0x01e0, 0x180, 0x003d);
102		return 0;
103	default:
104		return -EOPNOTSUPP;
105	}
106}
107
108static int
109r8a779f0_eth_serdes_chan_setting(struct r8a779f0_eth_serdes_channel *channel)
110{
111	int ret;
112
113	switch (channel->phy_interface) {
114	case PHY_INTERFACE_MODE_SGMII:
115		r8a779f0_eth_serdes_write32(channel->addr, 0x0000, 0x380, 0x2000);
116		r8a779f0_eth_serdes_write32(channel->addr, 0x01c0, 0x180, 0x0011);
117		r8a779f0_eth_serdes_write32(channel->addr, 0x0248, 0x180, 0x0540);
118		r8a779f0_eth_serdes_write32(channel->addr, 0x0258, 0x180, 0x0015);
119		r8a779f0_eth_serdes_write32(channel->addr, 0x0144, 0x180, 0x0100);
120		r8a779f0_eth_serdes_write32(channel->addr, 0x01a0, 0x180, 0x0000);
121		r8a779f0_eth_serdes_write32(channel->addr, 0x00d0, 0x180, 0x0002);
122		r8a779f0_eth_serdes_write32(channel->addr, 0x0150, 0x180, 0x0003);
123		r8a779f0_eth_serdes_write32(channel->addr, 0x00c8, 0x180, 0x0100);
124		r8a779f0_eth_serdes_write32(channel->addr, 0x0148, 0x180, 0x0100);
125		r8a779f0_eth_serdes_write32(channel->addr, 0x0174, 0x180, 0x0000);
126		r8a779f0_eth_serdes_write32(channel->addr, 0x0160, 0x180, 0x0007);
127		r8a779f0_eth_serdes_write32(channel->addr, 0x01ac, 0x180, 0x0000);
128		r8a779f0_eth_serdes_write32(channel->addr, 0x00c4, 0x180, 0x0310);
129		r8a779f0_eth_serdes_write32(channel->addr, 0x00c8, 0x180, 0x0101);
130		ret = r8a779f0_eth_serdes_reg_wait(channel, 0x00c8, 0x0180, BIT(0), 0);
131		if (ret)
132			return ret;
133
134		r8a779f0_eth_serdes_write32(channel->addr, 0x0148, 0x180, 0x0101);
135		ret = r8a779f0_eth_serdes_reg_wait(channel, 0x0148, 0x0180, BIT(0), 0);
136		if (ret)
137			return ret;
138
139		r8a779f0_eth_serdes_write32(channel->addr, 0x00c4, 0x180, 0x1310);
140		r8a779f0_eth_serdes_write32(channel->addr, 0x00d8, 0x180, 0x1800);
141		r8a779f0_eth_serdes_write32(channel->addr, 0x00dc, 0x180, 0x0000);
142		r8a779f0_eth_serdes_write32(channel->addr, 0x001c, 0x300, 0x0001);
143		r8a779f0_eth_serdes_write32(channel->addr, 0x0000, 0x380, 0x2100);
144		ret = r8a779f0_eth_serdes_reg_wait(channel, 0x0000, 0x0380, BIT(8), 0);
145		if (ret)
146			return ret;
147
148		if (channel->speed == 1000)
149			r8a779f0_eth_serdes_write32(channel->addr, 0x0000, 0x1f00, 0x0140);
150		else if (channel->speed == 100)
151			r8a779f0_eth_serdes_write32(channel->addr, 0x0000, 0x1f00, 0x2100);
152
153		/* For AN_ON */
154		r8a779f0_eth_serdes_write32(channel->addr, 0x0004, 0x1f80, 0x0005);
155		r8a779f0_eth_serdes_write32(channel->addr, 0x0028, 0x1f80, 0x07a1);
156		r8a779f0_eth_serdes_write32(channel->addr, 0x0000, 0x1f80, 0x0208);
157		break;
158	default:
159		return -EOPNOTSUPP;
160	}
161
162	return 0;
163}
164
165static int
166r8a779f0_eth_serdes_chan_speed(struct r8a779f0_eth_serdes_channel *channel)
167{
168	int ret;
169
170	switch (channel->phy_interface) {
171	case PHY_INTERFACE_MODE_SGMII:
172		/* For AN_ON */
173		if (channel->speed == 1000)
174			r8a779f0_eth_serdes_write32(channel->addr, 0x0000, 0x1f00, 0x1140);
175		else if (channel->speed == 100)
176			r8a779f0_eth_serdes_write32(channel->addr, 0x0000, 0x1f00, 0x3100);
177		ret = r8a779f0_eth_serdes_reg_wait(channel, 0x0008, 0x1f80, BIT(0), 1);
178		if (ret)
179			return ret;
180		r8a779f0_eth_serdes_write32(channel->addr, 0x0008, 0x1f80, 0x0000);
181		break;
182	default:
183		return -EOPNOTSUPP;
184	}
185
186	return 0;
187}
188
189
190static int r8a779f0_eth_serdes_monitor_linkup(struct r8a779f0_eth_serdes_channel *channel)
191{
192	int i, ret;
193
194	for (i = 0; i < R8A779F0_ETH_SERDES_NUM_RETRY_LINKUP; i++) {
195		ret = r8a779f0_eth_serdes_reg_wait(channel, 0x0004, 0x300,
196						   BIT(2), BIT(2));
197		if (!ret)
198			break;
199
200		/* restart */
201		r8a779f0_eth_serdes_write32(channel->addr, 0x0144, 0x180, 0x0100);
202		udelay(1);
203		r8a779f0_eth_serdes_write32(channel->addr, 0x0144, 0x180, 0x0000);
204	}
205
206	return ret;
207}
208
209static int r8a779f0_eth_serdes_hw_init(struct r8a779f0_eth_serdes_channel *channel)
210{
211	struct r8a779f0_eth_serdes_drv_data *dd = channel->dd;
212	int i, ret;
213
214	if (dd->initialized)
215		return 0;
216
217	reset_control_reset(dd->reset);
218
219	usleep_range(1000, 2000);
220
221	ret = r8a779f0_eth_serdes_common_init_ram(dd);
222	if (ret)
223		return ret;
224
225	for (i = 0; i < R8A779F0_ETH_SERDES_NUM; i++) {
226		ret = r8a779f0_eth_serdes_reg_wait(&dd->channel[i], 0x0000,
227						   0x300, BIT(15), 0);
228		if (ret)
229			return ret;
230	}
231
232	for (i = 0; i < R8A779F0_ETH_SERDES_NUM; i++)
233		r8a779f0_eth_serdes_write32(dd->channel[i].addr, 0x03d4, 0x380, 0x0443);
234
235	ret = r8a779f0_eth_serdes_common_setting(channel);
236	if (ret)
237		return ret;
238
239	for (i = 0; i < R8A779F0_ETH_SERDES_NUM; i++)
240		r8a779f0_eth_serdes_write32(dd->channel[i].addr, 0x03d0, 0x380, 0x0001);
241
242
243	r8a779f0_eth_serdes_write32(dd->addr, 0x0000, 0x380, 0x8000);
244
245	ret = r8a779f0_eth_serdes_common_init_ram(dd);
246	if (ret)
247		return ret;
248
249	return r8a779f0_eth_serdes_reg_wait(&dd->channel[0], 0x0000, 0x380, BIT(15), 0);
250}
251
252static int r8a779f0_eth_serdes_init(struct phy *p)
253{
254	struct r8a779f0_eth_serdes_channel *channel = phy_get_drvdata(p);
255	int ret;
256
257	ret = r8a779f0_eth_serdes_hw_init(channel);
258	if (!ret)
259		channel->dd->initialized = true;
260
261	return ret;
262}
263
264static int r8a779f0_eth_serdes_exit(struct phy *p)
265{
266	struct r8a779f0_eth_serdes_channel *channel = phy_get_drvdata(p);
267
268	channel->dd->initialized = false;
269
270	return 0;
271}
272
273static int r8a779f0_eth_serdes_hw_init_late(struct r8a779f0_eth_serdes_channel
274*channel)
275{
276	int ret;
277
278	ret = r8a779f0_eth_serdes_chan_setting(channel);
279	if (ret)
280		return ret;
281
282	ret = r8a779f0_eth_serdes_chan_speed(channel);
283	if (ret)
284		return ret;
285
286	r8a779f0_eth_serdes_write32(channel->addr, 0x03c0, 0x380, 0x0000);
287
288	r8a779f0_eth_serdes_write32(channel->addr, 0x03d0, 0x380, 0x0000);
289
290	return r8a779f0_eth_serdes_monitor_linkup(channel);
291}
292
293static int r8a779f0_eth_serdes_power_on(struct phy *p)
294{
295	struct r8a779f0_eth_serdes_channel *channel = phy_get_drvdata(p);
296
297	return r8a779f0_eth_serdes_hw_init_late(channel);
298}
299
300static int r8a779f0_eth_serdes_set_mode(struct phy *p, enum phy_mode mode,
301					int submode)
302{
303	struct r8a779f0_eth_serdes_channel *channel = phy_get_drvdata(p);
304
305	if (mode != PHY_MODE_ETHERNET)
306		return -EOPNOTSUPP;
307
308	switch (submode) {
309	case PHY_INTERFACE_MODE_GMII:
310	case PHY_INTERFACE_MODE_SGMII:
311	case PHY_INTERFACE_MODE_USXGMII:
312		channel->phy_interface = submode;
313		return 0;
314	default:
315		return -EOPNOTSUPP;
316	}
317}
318
319static int r8a779f0_eth_serdes_set_speed(struct phy *p, int speed)
320{
321	struct r8a779f0_eth_serdes_channel *channel = phy_get_drvdata(p);
322
323	channel->speed = speed;
324
325	return 0;
326}
327
328static const struct phy_ops r8a779f0_eth_serdes_ops = {
329	.init		= r8a779f0_eth_serdes_init,
330	.exit		= r8a779f0_eth_serdes_exit,
331	.power_on	= r8a779f0_eth_serdes_power_on,
332	.set_mode	= r8a779f0_eth_serdes_set_mode,
333	.set_speed	= r8a779f0_eth_serdes_set_speed,
334};
335
336static struct phy *r8a779f0_eth_serdes_xlate(struct device *dev,
337					     const struct of_phandle_args *args)
338{
339	struct r8a779f0_eth_serdes_drv_data *dd = dev_get_drvdata(dev);
340
341	if (args->args[0] >= R8A779F0_ETH_SERDES_NUM)
342		return ERR_PTR(-ENODEV);
343
344	return dd->channel[args->args[0]].phy;
345}
346
347static const struct of_device_id r8a779f0_eth_serdes_of_table[] = {
348	{ .compatible = "renesas,r8a779f0-ether-serdes", },
349	{ }
350};
351MODULE_DEVICE_TABLE(of, r8a779f0_eth_serdes_of_table);
352
353static int r8a779f0_eth_serdes_probe(struct platform_device *pdev)
354{
355	struct r8a779f0_eth_serdes_drv_data *dd;
356	struct phy_provider *provider;
357	int i;
358
359	dd = devm_kzalloc(&pdev->dev, sizeof(*dd), GFP_KERNEL);
360	if (!dd)
361		return -ENOMEM;
362
363	platform_set_drvdata(pdev, dd);
364	dd->pdev = pdev;
365	dd->addr = devm_platform_ioremap_resource(pdev, 0);
366	if (IS_ERR(dd->addr))
367		return PTR_ERR(dd->addr);
368
369	dd->reset = devm_reset_control_get(&pdev->dev, NULL);
370	if (IS_ERR(dd->reset))
371		return PTR_ERR(dd->reset);
372
373	for (i = 0; i < R8A779F0_ETH_SERDES_NUM; i++) {
374		struct r8a779f0_eth_serdes_channel *channel = &dd->channel[i];
375
376		channel->phy = devm_phy_create(&pdev->dev, NULL,
377					       &r8a779f0_eth_serdes_ops);
378		if (IS_ERR(channel->phy))
379			return PTR_ERR(channel->phy);
380		channel->addr = dd->addr + R8A779F0_ETH_SERDES_OFFSET * i;
381		channel->dd = dd;
382		channel->index = i;
383		phy_set_drvdata(channel->phy, channel);
384	}
385
386	provider = devm_of_phy_provider_register(&pdev->dev,
387						 r8a779f0_eth_serdes_xlate);
388	if (IS_ERR(provider))
389		return PTR_ERR(provider);
390
391	pm_runtime_enable(&pdev->dev);
392	pm_runtime_get_sync(&pdev->dev);
393
394	return 0;
395}
396
397static void r8a779f0_eth_serdes_remove(struct platform_device *pdev)
398{
399	pm_runtime_put(&pdev->dev);
400	pm_runtime_disable(&pdev->dev);
401
402	platform_set_drvdata(pdev, NULL);
403}
404
405static struct platform_driver r8a779f0_eth_serdes_driver_platform = {
406	.probe = r8a779f0_eth_serdes_probe,
407	.remove_new = r8a779f0_eth_serdes_remove,
408	.driver = {
409		.name = "r8a779f0_eth_serdes",
410		.of_match_table = r8a779f0_eth_serdes_of_table,
411	}
412};
413module_platform_driver(r8a779f0_eth_serdes_driver_platform);
414MODULE_AUTHOR("Yoshihiro Shimoda");
415MODULE_DESCRIPTION("Renesas Ethernet SERDES device driver");
416MODULE_LICENSE("GPL");
417