1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2014, The Linux Foundation. All rights reserved.
4  */
5 
6 #include <linux/io.h>
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/of.h>
10 #include <linux/of_address.h>
11 #include <linux/time.h>
12 #include <linux/delay.h>
13 #include <linux/clk.h>
14 #include <linux/slab.h>
15 #include <linux/platform_device.h>
16 #include <linux/phy/phy.h>
17 
18 struct qcom_ipq806x_sata_phy {
19 	void __iomem *mmio;
20 	struct clk *cfg_clk;
21 	struct device *dev;
22 };
23 
24 #define __set(v, a, b)	(((v) << (b)) & GENMASK(a, b))
25 
26 #define SATA_PHY_P0_PARAM0		0x200
27 #define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3(x)	__set(x, 17, 12)
28 #define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3_MASK	GENMASK(17, 12)
29 #define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN2(x)	__set(x, 11, 6)
30 #define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN2_MASK	GENMASK(11, 6)
31 #define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN1(x)	__set(x, 5, 0)
32 #define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN1_MASK	GENMASK(5, 0)
33 
34 #define SATA_PHY_P0_PARAM1		0x204
35 #define SATA_PHY_P0_PARAM1_RESERVED_BITS31_21(x)	__set(x, 31, 21)
36 #define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3(x)	__set(x, 20, 14)
37 #define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3_MASK	GENMASK(20, 14)
38 #define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2(x)	__set(x, 13, 7)
39 #define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2_MASK	GENMASK(13, 7)
40 #define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1(x)	__set(x, 6, 0)
41 #define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1_MASK	GENMASK(6, 0)
42 
43 #define SATA_PHY_P0_PARAM2		0x208
44 #define SATA_PHY_P0_PARAM2_RX_EQ(x)	__set(x, 20, 18)
45 #define SATA_PHY_P0_PARAM2_RX_EQ_MASK	GENMASK(20, 18)
46 
47 #define SATA_PHY_P0_PARAM3		0x20C
48 #define SATA_PHY_SSC_EN			0x8
49 #define SATA_PHY_P0_PARAM4		0x210
50 #define SATA_PHY_REF_SSP_EN		0x2
51 #define SATA_PHY_RESET			0x1
52 
53 static int qcom_ipq806x_sata_phy_init(struct phy *generic_phy)
54 {
55 	struct qcom_ipq806x_sata_phy *phy = phy_get_drvdata(generic_phy);
56 	u32 reg;
57 
58 	/* Setting SSC_EN to 1 */
59 	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM3);
60 	reg = reg | SATA_PHY_SSC_EN;
61 	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM3);
62 
63 	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM0) &
64 			~(SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3_MASK |
65 			  SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN2_MASK |
66 			  SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN1_MASK);
67 	reg |= SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3(0xf);
68 	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM0);
69 
70 	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM1) &
71 			~(SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3_MASK |
72 			  SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2_MASK |
73 			  SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1_MASK);
74 	reg |= SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3(0x55) |
75 		SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2(0x55) |
76 		SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1(0x55);
77 	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM1);
78 
79 	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM2) &
80 		~SATA_PHY_P0_PARAM2_RX_EQ_MASK;
81 	reg |= SATA_PHY_P0_PARAM2_RX_EQ(0x3);
82 	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM2);
83 
84 	/* Setting PHY_RESET to 1 */
85 	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
86 	reg = reg | SATA_PHY_RESET;
87 	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
88 
89 	/* Setting REF_SSP_EN to 1 */
90 	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
91 	reg = reg | SATA_PHY_REF_SSP_EN | SATA_PHY_RESET;
92 	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
93 
94 	/* make sure all changes complete before we let the PHY out of reset */
95 	mb();
96 
97 	/* sleep for max. 50us more to combine processor wakeups */
98 	usleep_range(20, 20 + 50);
99 
100 	/* Clearing PHY_RESET to 0 */
101 	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
102 	reg = reg & ~SATA_PHY_RESET;
103 	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
104 
105 	return 0;
106 }
107 
108 static int qcom_ipq806x_sata_phy_exit(struct phy *generic_phy)
109 {
110 	struct qcom_ipq806x_sata_phy *phy = phy_get_drvdata(generic_phy);
111 	u32 reg;
112 
113 	/* Setting PHY_RESET to 1 */
114 	reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
115 	reg = reg | SATA_PHY_RESET;
116 	writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
117 
118 	return 0;
119 }
120 
121 static const struct phy_ops qcom_ipq806x_sata_phy_ops = {
122 	.init		= qcom_ipq806x_sata_phy_init,
123 	.exit		= qcom_ipq806x_sata_phy_exit,
124 	.owner		= THIS_MODULE,
125 };
126 
127 static int qcom_ipq806x_sata_phy_probe(struct platform_device *pdev)
128 {
129 	struct qcom_ipq806x_sata_phy *phy;
130 	struct device *dev = &pdev->dev;
131 	struct phy_provider *phy_provider;
132 	struct phy *generic_phy;
133 	int ret;
134 
135 	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
136 	if (!phy)
137 		return -ENOMEM;
138 
139 	phy->mmio = devm_platform_ioremap_resource(pdev, 0);
140 	if (IS_ERR(phy->mmio))
141 		return PTR_ERR(phy->mmio);
142 
143 	generic_phy = devm_phy_create(dev, NULL, &qcom_ipq806x_sata_phy_ops);
144 	if (IS_ERR(generic_phy)) {
145 		dev_err(dev, "%s: failed to create phy\n", __func__);
146 		return PTR_ERR(generic_phy);
147 	}
148 
149 	phy->dev = dev;
150 	phy_set_drvdata(generic_phy, phy);
151 	platform_set_drvdata(pdev, phy);
152 
153 	phy->cfg_clk = devm_clk_get(dev, "cfg");
154 	if (IS_ERR(phy->cfg_clk)) {
155 		dev_err(dev, "Failed to get sata cfg clock\n");
156 		return PTR_ERR(phy->cfg_clk);
157 	}
158 
159 	ret = clk_prepare_enable(phy->cfg_clk);
160 	if (ret)
161 		return ret;
162 
163 	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
164 	if (IS_ERR(phy_provider)) {
165 		clk_disable_unprepare(phy->cfg_clk);
166 		dev_err(dev, "%s: failed to register phy\n", __func__);
167 		return PTR_ERR(phy_provider);
168 	}
169 
170 	return 0;
171 }
172 
173 static void qcom_ipq806x_sata_phy_remove(struct platform_device *pdev)
174 {
175 	struct qcom_ipq806x_sata_phy *phy = platform_get_drvdata(pdev);
176 
177 	clk_disable_unprepare(phy->cfg_clk);
178 }
179 
180 static const struct of_device_id qcom_ipq806x_sata_phy_of_match[] = {
181 	{ .compatible = "qcom,ipq806x-sata-phy" },
182 	{ },
183 };
184 MODULE_DEVICE_TABLE(of, qcom_ipq806x_sata_phy_of_match);
185 
186 static struct platform_driver qcom_ipq806x_sata_phy_driver = {
187 	.probe	= qcom_ipq806x_sata_phy_probe,
188 	.remove_new = qcom_ipq806x_sata_phy_remove,
189 	.driver = {
190 		.name	= "qcom-ipq806x-sata-phy",
191 		.of_match_table	= qcom_ipq806x_sata_phy_of_match,
192 	}
193 };
194 module_platform_driver(qcom_ipq806x_sata_phy_driver);
195 
196 MODULE_DESCRIPTION("QCOM IPQ806x SATA PHY driver");
197 MODULE_LICENSE("GPL v2");
198