1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * COMBPHY driver for HiSilicon STB SoCs
4 *
5 * Copyright (C) 2016-2017 HiSilicon Co., Ltd. http://www.hisilicon.com
6 *
7 * Authors: Jianguo Sun <sunjianguo1@huawei.com>
8 */
9
10 #include <linux/clk.h>
11 #include <linux/delay.h>
12 #include <linux/io.h>
13 #include <linux/kernel.h>
14 #include <linux/mfd/syscon.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/phy/phy.h>
18 #include <linux/platform_device.h>
19 #include <linux/regmap.h>
20 #include <linux/reset.h>
21 #include <dt-bindings/phy/phy.h>
22
23 #define COMBPHY_MODE_PCIE 0
24 #define COMBPHY_MODE_USB3 1
25 #define COMBPHY_MODE_SATA 2
26
27 #define COMBPHY_CFG_REG 0x0
28 #define COMBPHY_BYPASS_CODEC BIT(31)
29 #define COMBPHY_TEST_WRITE BIT(24)
30 #define COMBPHY_TEST_DATA_SHIFT 20
31 #define COMBPHY_TEST_DATA_MASK GENMASK(23, 20)
32 #define COMBPHY_TEST_ADDR_SHIFT 12
33 #define COMBPHY_TEST_ADDR_MASK GENMASK(16, 12)
34 #define COMBPHY_CLKREF_OUT_OEN BIT(0)
35
36 struct histb_combphy_mode {
37 int fixed;
38 int select;
39 u32 reg;
40 u32 shift;
41 u32 mask;
42 };
43
44 struct histb_combphy_priv {
45 void __iomem *mmio;
46 struct regmap *syscon;
47 struct reset_control *por_rst;
48 struct clk *ref_clk;
49 struct phy *phy;
50 struct histb_combphy_mode mode;
51 };
52
nano_register_write(struct histb_combphy_priv * priv,u32 addr,u32 data)53 static void nano_register_write(struct histb_combphy_priv *priv,
54 u32 addr, u32 data)
55 {
56 void __iomem *reg = priv->mmio + COMBPHY_CFG_REG;
57 u32 val;
58
59 /* Set up address and data for the write */
60 val = readl(reg);
61 val &= ~COMBPHY_TEST_ADDR_MASK;
62 val |= addr << COMBPHY_TEST_ADDR_SHIFT;
63 val &= ~COMBPHY_TEST_DATA_MASK;
64 val |= data << COMBPHY_TEST_DATA_SHIFT;
65 writel(val, reg);
66
67 /* Flip strobe control to trigger the write */
68 val &= ~COMBPHY_TEST_WRITE;
69 writel(val, reg);
70 val |= COMBPHY_TEST_WRITE;
71 writel(val, reg);
72 }
73
is_mode_fixed(struct histb_combphy_mode * mode)74 static int is_mode_fixed(struct histb_combphy_mode *mode)
75 {
76 return (mode->fixed != PHY_NONE) ? true : false;
77 }
78
histb_combphy_set_mode(struct histb_combphy_priv * priv)79 static int histb_combphy_set_mode(struct histb_combphy_priv *priv)
80 {
81 struct histb_combphy_mode *mode = &priv->mode;
82 struct regmap *syscon = priv->syscon;
83 u32 hw_sel;
84
85 if (is_mode_fixed(mode))
86 return 0;
87
88 switch (mode->select) {
89 case PHY_TYPE_SATA:
90 hw_sel = COMBPHY_MODE_SATA;
91 break;
92 case PHY_TYPE_PCIE:
93 hw_sel = COMBPHY_MODE_PCIE;
94 break;
95 case PHY_TYPE_USB3:
96 hw_sel = COMBPHY_MODE_USB3;
97 break;
98 default:
99 return -EINVAL;
100 }
101
102 return regmap_update_bits(syscon, mode->reg, mode->mask,
103 hw_sel << mode->shift);
104 }
105
histb_combphy_init(struct phy * phy)106 static int histb_combphy_init(struct phy *phy)
107 {
108 struct histb_combphy_priv *priv = phy_get_drvdata(phy);
109 u32 val;
110 int ret;
111
112 ret = histb_combphy_set_mode(priv);
113 if (ret)
114 return ret;
115
116 /* Clear bypass bit to enable encoding/decoding */
117 val = readl(priv->mmio + COMBPHY_CFG_REG);
118 val &= ~COMBPHY_BYPASS_CODEC;
119 writel(val, priv->mmio + COMBPHY_CFG_REG);
120
121 ret = clk_prepare_enable(priv->ref_clk);
122 if (ret)
123 return ret;
124
125 reset_control_deassert(priv->por_rst);
126
127 /* Enable EP clock */
128 val = readl(priv->mmio + COMBPHY_CFG_REG);
129 val |= COMBPHY_CLKREF_OUT_OEN;
130 writel(val, priv->mmio + COMBPHY_CFG_REG);
131
132 /* Need to wait for EP clock stable */
133 mdelay(5);
134
135 /* Configure nano phy registers as suggested by vendor */
136 nano_register_write(priv, 0x1, 0x8);
137 nano_register_write(priv, 0xc, 0x9);
138 nano_register_write(priv, 0x1a, 0x4);
139
140 return 0;
141 }
142
histb_combphy_exit(struct phy * phy)143 static int histb_combphy_exit(struct phy *phy)
144 {
145 struct histb_combphy_priv *priv = phy_get_drvdata(phy);
146 u32 val;
147
148 /* Disable EP clock */
149 val = readl(priv->mmio + COMBPHY_CFG_REG);
150 val &= ~COMBPHY_CLKREF_OUT_OEN;
151 writel(val, priv->mmio + COMBPHY_CFG_REG);
152
153 reset_control_assert(priv->por_rst);
154 clk_disable_unprepare(priv->ref_clk);
155
156 return 0;
157 }
158
159 static const struct phy_ops histb_combphy_ops = {
160 .init = histb_combphy_init,
161 .exit = histb_combphy_exit,
162 .owner = THIS_MODULE,
163 };
164
histb_combphy_xlate(struct device * dev,struct of_phandle_args * args)165 static struct phy *histb_combphy_xlate(struct device *dev,
166 struct of_phandle_args *args)
167 {
168 struct histb_combphy_priv *priv = dev_get_drvdata(dev);
169 struct histb_combphy_mode *mode = &priv->mode;
170
171 if (args->args_count < 1) {
172 dev_err(dev, "invalid number of arguments\n");
173 return ERR_PTR(-EINVAL);
174 }
175
176 mode->select = args->args[0];
177
178 if (mode->select < PHY_TYPE_SATA || mode->select > PHY_TYPE_USB3) {
179 dev_err(dev, "invalid phy mode select argument\n");
180 return ERR_PTR(-EINVAL);
181 }
182
183 if (is_mode_fixed(mode) && mode->select != mode->fixed) {
184 dev_err(dev, "mode select %d mismatch fixed phy mode %d\n",
185 mode->select, mode->fixed);
186 return ERR_PTR(-EINVAL);
187 }
188
189 return priv->phy;
190 }
191
histb_combphy_probe(struct platform_device * pdev)192 static int histb_combphy_probe(struct platform_device *pdev)
193 {
194 struct phy_provider *phy_provider;
195 struct device *dev = &pdev->dev;
196 struct histb_combphy_priv *priv;
197 struct device_node *np = dev->of_node;
198 struct histb_combphy_mode *mode;
199 u32 vals[3];
200 int ret;
201
202 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
203 if (!priv)
204 return -ENOMEM;
205
206 priv->mmio = devm_platform_ioremap_resource(pdev, 0);
207 if (IS_ERR(priv->mmio)) {
208 ret = PTR_ERR(priv->mmio);
209 return ret;
210 }
211
212 priv->syscon = syscon_node_to_regmap(np->parent);
213 if (IS_ERR(priv->syscon)) {
214 dev_err(dev, "failed to find peri_ctrl syscon regmap\n");
215 return PTR_ERR(priv->syscon);
216 }
217
218 mode = &priv->mode;
219 mode->fixed = PHY_NONE;
220
221 ret = of_property_read_u32(np, "hisilicon,fixed-mode", &mode->fixed);
222 if (ret == 0)
223 dev_dbg(dev, "found fixed phy mode %d\n", mode->fixed);
224
225 ret = of_property_read_u32_array(np, "hisilicon,mode-select-bits",
226 vals, ARRAY_SIZE(vals));
227 if (ret == 0) {
228 if (is_mode_fixed(mode)) {
229 dev_err(dev, "found select bits for fixed mode phy\n");
230 return -EINVAL;
231 }
232
233 mode->reg = vals[0];
234 mode->shift = vals[1];
235 mode->mask = vals[2];
236 dev_dbg(dev, "found mode select bits\n");
237 } else {
238 if (!is_mode_fixed(mode)) {
239 dev_err(dev, "no valid select bits found for non-fixed phy\n");
240 return -ENODEV;
241 }
242 }
243
244 priv->ref_clk = devm_clk_get(dev, NULL);
245 if (IS_ERR(priv->ref_clk)) {
246 dev_err(dev, "failed to find ref clock\n");
247 return PTR_ERR(priv->ref_clk);
248 }
249
250 priv->por_rst = devm_reset_control_get(dev, NULL);
251 if (IS_ERR(priv->por_rst)) {
252 dev_err(dev, "failed to get poweron reset\n");
253 return PTR_ERR(priv->por_rst);
254 }
255
256 priv->phy = devm_phy_create(dev, NULL, &histb_combphy_ops);
257 if (IS_ERR(priv->phy)) {
258 dev_err(dev, "failed to create combphy\n");
259 return PTR_ERR(priv->phy);
260 }
261
262 dev_set_drvdata(dev, priv);
263 phy_set_drvdata(priv->phy, priv);
264
265 phy_provider = devm_of_phy_provider_register(dev, histb_combphy_xlate);
266 return PTR_ERR_OR_ZERO(phy_provider);
267 }
268
269 static const struct of_device_id histb_combphy_of_match[] = {
270 { .compatible = "hisilicon,hi3798cv200-combphy" },
271 { },
272 };
273 MODULE_DEVICE_TABLE(of, histb_combphy_of_match);
274
275 static struct platform_driver histb_combphy_driver = {
276 .probe = histb_combphy_probe,
277 .driver = {
278 .name = "combphy",
279 .of_match_table = histb_combphy_of_match,
280 },
281 };
282 module_platform_driver(histb_combphy_driver);
283
284 MODULE_DESCRIPTION("HiSilicon STB COMBPHY driver");
285 MODULE_LICENSE("GPL v2");
286