1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * phy-uniphier-pcie.c - PHY driver for UniPhier PCIe controller
4 * Copyright 2018, Socionext Inc.
5 * Author: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
6 */
7
8 #include <linux/bitops.h>
9 #include <linux/bitfield.h>
10 #include <linux/clk.h>
11 #include <linux/iopoll.h>
12 #include <linux/mfd/syscon.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/phy/phy.h>
16 #include <linux/platform_device.h>
17 #include <linux/regmap.h>
18 #include <linux/reset.h>
19 #include <linux/resource.h>
20
21 /* PHY */
22 #define PCL_PHY_CLKCTRL 0x0000
23 #define PORT_SEL_MASK GENMASK(11, 9)
24 #define PORT_SEL_1 FIELD_PREP(PORT_SEL_MASK, 1)
25
26 #define PCL_PHY_TEST_I 0x2000
27 #define TESTI_DAT_MASK GENMASK(13, 6)
28 #define TESTI_ADR_MASK GENMASK(5, 1)
29 #define TESTI_WR_EN BIT(0)
30 #define TESTIO_PHY_SHIFT 16
31
32 #define PCL_PHY_TEST_O 0x2004
33 #define TESTO_DAT_MASK GENMASK(7, 0)
34
35 #define PCL_PHY_RESET 0x200c
36 #define PCL_PHY_RESET_N_MNMODE BIT(8) /* =1:manual */
37 #define PCL_PHY_RESET_N BIT(0) /* =1:deasssert */
38
39 /* SG */
40 #define SG_USBPCIESEL 0x590
41 #define SG_USBPCIESEL_PCIE BIT(0)
42
43 /* SC */
44 #define SC_US3SRCSEL 0x2244
45 #define SC_US3SRCSEL_2LANE GENMASK(9, 8)
46
47 #define PCL_PHY_R00 0
48 #define RX_EQ_ADJ_EN BIT(3) /* enable for EQ adjustment */
49 #define PCL_PHY_R06 6
50 #define RX_EQ_ADJ GENMASK(5, 0) /* EQ adjustment value */
51 #define RX_EQ_ADJ_VAL 0
52 #define PCL_PHY_R26 26
53 #define VCO_CTRL GENMASK(7, 4) /* Tx VCO adjustment value */
54 #define VCO_CTRL_INIT_VAL 5
55 #define PCL_PHY_R28 28
56 #define VCOPLL_CLMP GENMASK(3, 2) /* Tx VCOPLL clamp mode */
57 #define VCOPLL_CLMP_VAL 0
58
59 struct uniphier_pciephy_priv {
60 void __iomem *base;
61 struct device *dev;
62 struct clk *clk, *clk_gio;
63 struct reset_control *rst, *rst_gio;
64 const struct uniphier_pciephy_soc_data *data;
65 };
66
67 struct uniphier_pciephy_soc_data {
68 bool is_legacy;
69 bool is_dual_phy;
70 void (*set_phymode)(struct regmap *regmap);
71 };
72
uniphier_pciephy_testio_write(struct uniphier_pciephy_priv * priv,int id,u32 data)73 static void uniphier_pciephy_testio_write(struct uniphier_pciephy_priv *priv,
74 int id, u32 data)
75 {
76 if (id)
77 data <<= TESTIO_PHY_SHIFT;
78
79 /* need to read TESTO twice after accessing TESTI */
80 writel(data, priv->base + PCL_PHY_TEST_I);
81 readl(priv->base + PCL_PHY_TEST_O);
82 readl(priv->base + PCL_PHY_TEST_O);
83 }
84
uniphier_pciephy_testio_read(struct uniphier_pciephy_priv * priv,int id)85 static u32 uniphier_pciephy_testio_read(struct uniphier_pciephy_priv *priv, int id)
86 {
87 u32 val = readl(priv->base + PCL_PHY_TEST_O);
88
89 if (id)
90 val >>= TESTIO_PHY_SHIFT;
91
92 return val & TESTO_DAT_MASK;
93 }
94
uniphier_pciephy_set_param(struct uniphier_pciephy_priv * priv,int id,u32 reg,u32 mask,u32 param)95 static void uniphier_pciephy_set_param(struct uniphier_pciephy_priv *priv,
96 int id, u32 reg, u32 mask, u32 param)
97 {
98 u32 val;
99
100 /* read previous data */
101 val = FIELD_PREP(TESTI_DAT_MASK, 1);
102 val |= FIELD_PREP(TESTI_ADR_MASK, reg);
103 uniphier_pciephy_testio_write(priv, id, val);
104 val = uniphier_pciephy_testio_read(priv, id);
105
106 /* update value */
107 val &= ~mask;
108 val |= mask & param;
109 val = FIELD_PREP(TESTI_DAT_MASK, val);
110 val |= FIELD_PREP(TESTI_ADR_MASK, reg);
111 uniphier_pciephy_testio_write(priv, id, val);
112 uniphier_pciephy_testio_write(priv, id, val | TESTI_WR_EN);
113 uniphier_pciephy_testio_write(priv, id, val);
114
115 /* read current data as dummy */
116 val = FIELD_PREP(TESTI_DAT_MASK, 1);
117 val |= FIELD_PREP(TESTI_ADR_MASK, reg);
118 uniphier_pciephy_testio_write(priv, id, val);
119 uniphier_pciephy_testio_read(priv, id);
120 }
121
uniphier_pciephy_assert(struct uniphier_pciephy_priv * priv)122 static void uniphier_pciephy_assert(struct uniphier_pciephy_priv *priv)
123 {
124 u32 val;
125
126 val = readl(priv->base + PCL_PHY_RESET);
127 val &= ~PCL_PHY_RESET_N;
128 val |= PCL_PHY_RESET_N_MNMODE;
129 writel(val, priv->base + PCL_PHY_RESET);
130 }
131
uniphier_pciephy_deassert(struct uniphier_pciephy_priv * priv)132 static void uniphier_pciephy_deassert(struct uniphier_pciephy_priv *priv)
133 {
134 u32 val;
135
136 val = readl(priv->base + PCL_PHY_RESET);
137 val |= PCL_PHY_RESET_N_MNMODE | PCL_PHY_RESET_N;
138 writel(val, priv->base + PCL_PHY_RESET);
139 }
140
uniphier_pciephy_init(struct phy * phy)141 static int uniphier_pciephy_init(struct phy *phy)
142 {
143 struct uniphier_pciephy_priv *priv = phy_get_drvdata(phy);
144 u32 val;
145 int ret, id;
146
147 ret = clk_prepare_enable(priv->clk);
148 if (ret)
149 return ret;
150
151 ret = clk_prepare_enable(priv->clk_gio);
152 if (ret)
153 goto out_clk_disable;
154
155 ret = reset_control_deassert(priv->rst);
156 if (ret)
157 goto out_clk_gio_disable;
158
159 ret = reset_control_deassert(priv->rst_gio);
160 if (ret)
161 goto out_rst_assert;
162
163 /* support only 1 port */
164 val = readl(priv->base + PCL_PHY_CLKCTRL);
165 val &= ~PORT_SEL_MASK;
166 val |= PORT_SEL_1;
167 writel(val, priv->base + PCL_PHY_CLKCTRL);
168
169 /* legacy controller doesn't have phy_reset and parameters */
170 if (priv->data->is_legacy)
171 return 0;
172
173 for (id = 0; id < (priv->data->is_dual_phy ? 2 : 1); id++) {
174 uniphier_pciephy_set_param(priv, id, PCL_PHY_R00,
175 RX_EQ_ADJ_EN, RX_EQ_ADJ_EN);
176 uniphier_pciephy_set_param(priv, id, PCL_PHY_R06, RX_EQ_ADJ,
177 FIELD_PREP(RX_EQ_ADJ, RX_EQ_ADJ_VAL));
178 uniphier_pciephy_set_param(priv, id, PCL_PHY_R26, VCO_CTRL,
179 FIELD_PREP(VCO_CTRL, VCO_CTRL_INIT_VAL));
180 uniphier_pciephy_set_param(priv, id, PCL_PHY_R28, VCOPLL_CLMP,
181 FIELD_PREP(VCOPLL_CLMP, VCOPLL_CLMP_VAL));
182 }
183 usleep_range(1, 10);
184
185 uniphier_pciephy_deassert(priv);
186 usleep_range(1, 10);
187
188 return 0;
189
190 out_rst_assert:
191 reset_control_assert(priv->rst);
192 out_clk_gio_disable:
193 clk_disable_unprepare(priv->clk_gio);
194 out_clk_disable:
195 clk_disable_unprepare(priv->clk);
196
197 return ret;
198 }
199
uniphier_pciephy_exit(struct phy * phy)200 static int uniphier_pciephy_exit(struct phy *phy)
201 {
202 struct uniphier_pciephy_priv *priv = phy_get_drvdata(phy);
203
204 if (!priv->data->is_legacy)
205 uniphier_pciephy_assert(priv);
206 reset_control_assert(priv->rst_gio);
207 reset_control_assert(priv->rst);
208 clk_disable_unprepare(priv->clk_gio);
209 clk_disable_unprepare(priv->clk);
210
211 return 0;
212 }
213
214 static const struct phy_ops uniphier_pciephy_ops = {
215 .init = uniphier_pciephy_init,
216 .exit = uniphier_pciephy_exit,
217 .owner = THIS_MODULE,
218 };
219
uniphier_pciephy_probe(struct platform_device * pdev)220 static int uniphier_pciephy_probe(struct platform_device *pdev)
221 {
222 struct uniphier_pciephy_priv *priv;
223 struct phy_provider *phy_provider;
224 struct device *dev = &pdev->dev;
225 struct regmap *regmap;
226 struct phy *phy;
227
228 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
229 if (!priv)
230 return -ENOMEM;
231
232 priv->data = of_device_get_match_data(dev);
233 if (WARN_ON(!priv->data))
234 return -EINVAL;
235
236 priv->dev = dev;
237
238 priv->base = devm_platform_ioremap_resource(pdev, 0);
239 if (IS_ERR(priv->base))
240 return PTR_ERR(priv->base);
241
242 if (priv->data->is_legacy) {
243 priv->clk_gio = devm_clk_get(dev, "gio");
244 if (IS_ERR(priv->clk_gio))
245 return PTR_ERR(priv->clk_gio);
246
247 priv->rst_gio =
248 devm_reset_control_get_shared(dev, "gio");
249 if (IS_ERR(priv->rst_gio))
250 return PTR_ERR(priv->rst_gio);
251
252 priv->clk = devm_clk_get(dev, "link");
253 if (IS_ERR(priv->clk))
254 return PTR_ERR(priv->clk);
255
256 priv->rst = devm_reset_control_get_shared(dev, "link");
257 if (IS_ERR(priv->rst))
258 return PTR_ERR(priv->rst);
259 } else {
260 priv->clk = devm_clk_get(dev, NULL);
261 if (IS_ERR(priv->clk))
262 return PTR_ERR(priv->clk);
263
264 priv->rst = devm_reset_control_get_shared(dev, NULL);
265 if (IS_ERR(priv->rst))
266 return PTR_ERR(priv->rst);
267 }
268
269 phy = devm_phy_create(dev, dev->of_node, &uniphier_pciephy_ops);
270 if (IS_ERR(phy))
271 return PTR_ERR(phy);
272
273 regmap = syscon_regmap_lookup_by_phandle(dev->of_node,
274 "socionext,syscon");
275 if (!IS_ERR(regmap) && priv->data->set_phymode)
276 priv->data->set_phymode(regmap);
277
278 phy_set_drvdata(phy, priv);
279 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
280
281 return PTR_ERR_OR_ZERO(phy_provider);
282 }
283
uniphier_pciephy_ld20_setmode(struct regmap * regmap)284 static void uniphier_pciephy_ld20_setmode(struct regmap *regmap)
285 {
286 regmap_update_bits(regmap, SG_USBPCIESEL,
287 SG_USBPCIESEL_PCIE, SG_USBPCIESEL_PCIE);
288 }
289
uniphier_pciephy_nx1_setmode(struct regmap * regmap)290 static void uniphier_pciephy_nx1_setmode(struct regmap *regmap)
291 {
292 regmap_update_bits(regmap, SC_US3SRCSEL,
293 SC_US3SRCSEL_2LANE, SC_US3SRCSEL_2LANE);
294 }
295
296 static const struct uniphier_pciephy_soc_data uniphier_pro5_data = {
297 .is_legacy = true,
298 };
299
300 static const struct uniphier_pciephy_soc_data uniphier_ld20_data = {
301 .is_legacy = false,
302 .is_dual_phy = false,
303 .set_phymode = uniphier_pciephy_ld20_setmode,
304 };
305
306 static const struct uniphier_pciephy_soc_data uniphier_pxs3_data = {
307 .is_legacy = false,
308 .is_dual_phy = false,
309 };
310
311 static const struct uniphier_pciephy_soc_data uniphier_nx1_data = {
312 .is_legacy = false,
313 .is_dual_phy = true,
314 .set_phymode = uniphier_pciephy_nx1_setmode,
315 };
316
317 static const struct of_device_id uniphier_pciephy_match[] = {
318 {
319 .compatible = "socionext,uniphier-pro5-pcie-phy",
320 .data = &uniphier_pro5_data,
321 },
322 {
323 .compatible = "socionext,uniphier-ld20-pcie-phy",
324 .data = &uniphier_ld20_data,
325 },
326 {
327 .compatible = "socionext,uniphier-pxs3-pcie-phy",
328 .data = &uniphier_pxs3_data,
329 },
330 {
331 .compatible = "socionext,uniphier-nx1-pcie-phy",
332 .data = &uniphier_nx1_data,
333 },
334 { /* sentinel */ },
335 };
336 MODULE_DEVICE_TABLE(of, uniphier_pciephy_match);
337
338 static struct platform_driver uniphier_pciephy_driver = {
339 .probe = uniphier_pciephy_probe,
340 .driver = {
341 .name = "uniphier-pcie-phy",
342 .of_match_table = uniphier_pciephy_match,
343 },
344 };
345 module_platform_driver(uniphier_pciephy_driver);
346
347 MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
348 MODULE_DESCRIPTION("UniPhier PHY driver for PCIe controller");
349 MODULE_LICENSE("GPL v2");
350