1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Rockchip PCIE3.0 phy driver
4  *
5  * Copyright (C) 2022 Rockchip Electronics Co., Ltd.
6  */
7 
8 #include <linux/clk.h>
9 #include <linux/delay.h>
10 #include <linux/io.h>
11 #include <linux/iopoll.h>
12 #include <linux/kernel.h>
13 #include <linux/mfd/syscon.h>
14 #include <linux/module.h>
15 #include <linux/of_device.h>
16 #include <linux/phy/pcie.h>
17 #include <linux/phy/phy.h>
18 #include <linux/regmap.h>
19 #include <linux/reset.h>
20 
21 /* Register for RK3568 */
22 #define GRF_PCIE30PHY_CON1			0x4
23 #define GRF_PCIE30PHY_CON6			0x18
24 #define GRF_PCIE30PHY_CON9			0x24
25 #define GRF_PCIE30PHY_DA_OCM			(BIT(15) | BIT(31))
26 #define GRF_PCIE30PHY_STATUS0			0x80
27 #define GRF_PCIE30PHY_WR_EN			(0xf << 16)
28 #define SRAM_INIT_DONE(reg)			(reg & BIT(14))
29 
30 #define RK3568_BIFURCATION_LANE_0_1		BIT(0)
31 
32 /* Register for RK3588 */
33 #define PHP_GRF_PCIESEL_CON			0x100
34 #define RK3588_PCIE3PHY_GRF_CMN_CON0		0x0
35 #define RK3588_PCIE3PHY_GRF_PHY0_STATUS1	0x904
36 #define RK3588_PCIE3PHY_GRF_PHY1_STATUS1	0xa04
37 #define RK3588_SRAM_INIT_DONE(reg)		(reg & BIT(0))
38 
39 #define RK3588_BIFURCATION_LANE_0_1		BIT(0)
40 #define RK3588_BIFURCATION_LANE_2_3		BIT(1)
41 #define RK3588_LANE_AGGREGATION		BIT(2)
42 
43 struct rockchip_p3phy_ops;
44 
45 struct rockchip_p3phy_priv {
46 	const struct rockchip_p3phy_ops *ops;
47 	void __iomem *mmio;
48 	/* mode: RC, EP */
49 	int mode;
50 	/* pcie30_phymode: Aggregation, Bifurcation */
51 	int pcie30_phymode;
52 	struct regmap *phy_grf;
53 	struct regmap *pipe_grf;
54 	struct reset_control *p30phy;
55 	struct phy *phy;
56 	struct clk_bulk_data *clks;
57 	int num_clks;
58 	int num_lanes;
59 	u32 lanes[4];
60 };
61 
62 struct rockchip_p3phy_ops {
63 	int (*phy_init)(struct rockchip_p3phy_priv *priv);
64 };
65 
66 static int rockchip_p3phy_set_mode(struct phy *phy, enum phy_mode mode, int submode)
67 {
68 	struct rockchip_p3phy_priv *priv = phy_get_drvdata(phy);
69 
70 	/* Actually We don't care EP/RC mode, but just record it */
71 	switch (submode) {
72 	case PHY_MODE_PCIE_RC:
73 		priv->mode = PHY_MODE_PCIE_RC;
74 		break;
75 	case PHY_MODE_PCIE_EP:
76 		priv->mode = PHY_MODE_PCIE_EP;
77 		break;
78 	default:
79 		dev_err(&phy->dev, "%s, invalid mode\n", __func__);
80 		return -EINVAL;
81 	}
82 
83 	return 0;
84 }
85 
86 static int rockchip_p3phy_rk3568_init(struct rockchip_p3phy_priv *priv)
87 {
88 	struct phy *phy = priv->phy;
89 	bool bifurcation = false;
90 	int ret;
91 	u32 reg;
92 
93 	/* Deassert PCIe PMA output clamp mode */
94 	regmap_write(priv->phy_grf, GRF_PCIE30PHY_CON9, GRF_PCIE30PHY_DA_OCM);
95 
96 	for (int i = 0; i < priv->num_lanes; i++) {
97 		dev_info(&phy->dev, "lane number %d, val %d\n", i, priv->lanes[i]);
98 		if (priv->lanes[i] > 1)
99 			bifurcation = true;
100 	}
101 
102 	/* Set bifurcation if needed, and it doesn't care RC/EP */
103 	if (bifurcation) {
104 		dev_info(&phy->dev, "bifurcation enabled\n");
105 		regmap_write(priv->phy_grf, GRF_PCIE30PHY_CON6,
106 			     GRF_PCIE30PHY_WR_EN | RK3568_BIFURCATION_LANE_0_1);
107 		regmap_write(priv->phy_grf, GRF_PCIE30PHY_CON1,
108 			     GRF_PCIE30PHY_DA_OCM);
109 	} else {
110 		dev_dbg(&phy->dev, "bifurcation disabled\n");
111 		regmap_write(priv->phy_grf, GRF_PCIE30PHY_CON6,
112 			     GRF_PCIE30PHY_WR_EN & ~RK3568_BIFURCATION_LANE_0_1);
113 	}
114 
115 	reset_control_deassert(priv->p30phy);
116 
117 	ret = regmap_read_poll_timeout(priv->phy_grf,
118 				       GRF_PCIE30PHY_STATUS0,
119 				       reg, SRAM_INIT_DONE(reg),
120 				       0, 500);
121 	if (ret)
122 		dev_err(&priv->phy->dev, "%s: lock failed 0x%x, check input refclk and power supply\n",
123 		       __func__, reg);
124 	return ret;
125 }
126 
127 static const struct rockchip_p3phy_ops rk3568_ops = {
128 	.phy_init = rockchip_p3phy_rk3568_init,
129 };
130 
131 static int rockchip_p3phy_rk3588_init(struct rockchip_p3phy_priv *priv)
132 {
133 	u32 reg = 0;
134 	u8 mode = 0;
135 	int ret;
136 
137 	/* Deassert PCIe PMA output clamp mode */
138 	regmap_write(priv->phy_grf, RK3588_PCIE3PHY_GRF_CMN_CON0, BIT(8) | BIT(24));
139 
140 	/* Set bifurcation if needed */
141 	for (int i = 0; i < priv->num_lanes; i++) {
142 		if (!priv->lanes[i])
143 			mode |= (BIT(i) << 3);
144 
145 		if (priv->lanes[i] > 1)
146 			mode |= (BIT(i) >> 1);
147 	}
148 
149 	if (!mode)
150 		reg = RK3588_LANE_AGGREGATION;
151 	else {
152 		if (mode & (BIT(0) | BIT(1)))
153 			reg |= RK3588_BIFURCATION_LANE_0_1;
154 
155 		if (mode & (BIT(2) | BIT(3)))
156 			reg |= RK3588_BIFURCATION_LANE_2_3;
157 	}
158 
159 	regmap_write(priv->phy_grf, RK3588_PCIE3PHY_GRF_CMN_CON0, (0x7<<16) | reg);
160 
161 	/* Set pcie1ln_sel in PHP_GRF_PCIESEL_CON */
162 	if (!IS_ERR(priv->pipe_grf)) {
163 		reg = (mode & (BIT(6) | BIT(7))) >> 6;
164 		if (reg)
165 			regmap_write(priv->pipe_grf, PHP_GRF_PCIESEL_CON,
166 				     (reg << 16) | reg);
167 	}
168 
169 	reset_control_deassert(priv->p30phy);
170 
171 	ret = regmap_read_poll_timeout(priv->phy_grf,
172 				       RK3588_PCIE3PHY_GRF_PHY0_STATUS1,
173 				       reg, RK3588_SRAM_INIT_DONE(reg),
174 				       0, 500);
175 	ret |= regmap_read_poll_timeout(priv->phy_grf,
176 					RK3588_PCIE3PHY_GRF_PHY1_STATUS1,
177 					reg, RK3588_SRAM_INIT_DONE(reg),
178 					0, 500);
179 	if (ret)
180 		dev_err(&priv->phy->dev, "lock failed 0x%x, check input refclk and power supply\n",
181 			reg);
182 	return ret;
183 }
184 
185 static const struct rockchip_p3phy_ops rk3588_ops = {
186 	.phy_init = rockchip_p3phy_rk3588_init,
187 };
188 
189 static int rochchip_p3phy_init(struct phy *phy)
190 {
191 	struct rockchip_p3phy_priv *priv = phy_get_drvdata(phy);
192 	int ret;
193 
194 	ret = clk_bulk_prepare_enable(priv->num_clks, priv->clks);
195 	if (ret) {
196 		dev_err(&priv->phy->dev, "failed to enable PCIe bulk clks %d\n", ret);
197 		return ret;
198 	}
199 
200 	reset_control_assert(priv->p30phy);
201 	udelay(1);
202 
203 	if (priv->ops->phy_init) {
204 		ret = priv->ops->phy_init(priv);
205 		if (ret)
206 			clk_bulk_disable_unprepare(priv->num_clks, priv->clks);
207 	}
208 
209 	return ret;
210 }
211 
212 static int rochchip_p3phy_exit(struct phy *phy)
213 {
214 	struct rockchip_p3phy_priv *priv = phy_get_drvdata(phy);
215 
216 	clk_bulk_disable_unprepare(priv->num_clks, priv->clks);
217 	reset_control_assert(priv->p30phy);
218 	return 0;
219 }
220 
221 static const struct phy_ops rochchip_p3phy_ops = {
222 	.init = rochchip_p3phy_init,
223 	.exit = rochchip_p3phy_exit,
224 	.set_mode = rockchip_p3phy_set_mode,
225 	.owner = THIS_MODULE,
226 };
227 
228 static int rockchip_p3phy_probe(struct platform_device *pdev)
229 {
230 	struct phy_provider *phy_provider;
231 	struct device *dev = &pdev->dev;
232 	struct rockchip_p3phy_priv *priv;
233 	struct device_node *np = dev->of_node;
234 	int ret;
235 
236 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
237 	if (!priv)
238 		return -ENOMEM;
239 
240 	priv->mmio = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
241 	if (IS_ERR(priv->mmio)) {
242 		ret = PTR_ERR(priv->mmio);
243 		return ret;
244 	}
245 
246 	priv->ops = of_device_get_match_data(&pdev->dev);
247 	if (!priv->ops) {
248 		dev_err(dev, "no of match data provided\n");
249 		return -EINVAL;
250 	}
251 
252 	priv->phy_grf = syscon_regmap_lookup_by_phandle(np, "rockchip,phy-grf");
253 	if (IS_ERR(priv->phy_grf)) {
254 		dev_err(dev, "failed to find rockchip,phy_grf regmap\n");
255 		return PTR_ERR(priv->phy_grf);
256 	}
257 
258 	if (of_device_is_compatible(np, "rockchip,rk3588-pcie3-phy")) {
259 		priv->pipe_grf =
260 			syscon_regmap_lookup_by_phandle(dev->of_node,
261 							"rockchip,pipe-grf");
262 		if (IS_ERR(priv->pipe_grf))
263 			dev_info(dev, "failed to find rockchip,pipe_grf regmap\n");
264 	} else {
265 		priv->pipe_grf = NULL;
266 	}
267 
268 	priv->num_lanes = of_property_read_variable_u32_array(dev->of_node, "data-lanes",
269 							     priv->lanes, 2,
270 							     ARRAY_SIZE(priv->lanes));
271 
272 	/* if no data-lanes assume aggregation */
273 	if (priv->num_lanes == -EINVAL) {
274 		dev_dbg(dev, "no data-lanes property found\n");
275 		priv->num_lanes = 1;
276 		priv->lanes[0] = 1;
277 	} else if (priv->num_lanes < 0) {
278 		dev_err(dev, "failed to read data-lanes property %d\n", priv->num_lanes);
279 		return priv->num_lanes;
280 	}
281 
282 	priv->phy = devm_phy_create(dev, NULL, &rochchip_p3phy_ops);
283 	if (IS_ERR(priv->phy)) {
284 		dev_err(dev, "failed to create combphy\n");
285 		return PTR_ERR(priv->phy);
286 	}
287 
288 	priv->p30phy = devm_reset_control_get_optional_exclusive(dev, "phy");
289 	if (IS_ERR(priv->p30phy)) {
290 		return dev_err_probe(dev, PTR_ERR(priv->p30phy),
291 				     "failed to get phy reset control\n");
292 	}
293 	if (!priv->p30phy)
294 		dev_info(dev, "no phy reset control specified\n");
295 
296 	priv->num_clks = devm_clk_bulk_get_all(dev, &priv->clks);
297 	if (priv->num_clks < 1)
298 		return -ENODEV;
299 
300 	dev_set_drvdata(dev, priv);
301 	phy_set_drvdata(priv->phy, priv);
302 	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
303 	return PTR_ERR_OR_ZERO(phy_provider);
304 }
305 
306 static const struct of_device_id rockchip_p3phy_of_match[] = {
307 	{ .compatible = "rockchip,rk3568-pcie3-phy", .data = &rk3568_ops },
308 	{ .compatible = "rockchip,rk3588-pcie3-phy", .data = &rk3588_ops },
309 	{ },
310 };
311 MODULE_DEVICE_TABLE(of, rockchip_p3phy_of_match);
312 
313 static struct platform_driver rockchip_p3phy_driver = {
314 	.probe	= rockchip_p3phy_probe,
315 	.driver = {
316 		.name = "rockchip-snps-pcie3-phy",
317 		.of_match_table = rockchip_p3phy_of_match,
318 	},
319 };
320 module_platform_driver(rockchip_p3phy_driver);
321 MODULE_DESCRIPTION("Rockchip Synopsys PCIe 3.0 PHY driver");
322 MODULE_LICENSE("GPL");
323