xref: /linux/drivers/phy/marvell/phy-pxa-28nm-hsic.c (revision 37744feebc086908fd89760650f458ab19071750)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2015 Linaro, Ltd.
4  * Rob Herring <robh@kernel.org>
5  *
6  * Based on vendor driver:
7  * Copyright (C) 2013 Marvell Inc.
8  * Author: Chao Xie <xiechao.mail@gmail.com>
9  */
10 
11 #include <linux/delay.h>
12 #include <linux/slab.h>
13 #include <linux/of.h>
14 #include <linux/io.h>
15 #include <linux/err.h>
16 #include <linux/clk.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 #include <linux/phy/phy.h>
20 
21 #define PHY_28NM_HSIC_CTRL			0x08
22 #define PHY_28NM_HSIC_IMPCAL_CAL		0x18
23 #define PHY_28NM_HSIC_PLL_CTRL01		0x1c
24 #define PHY_28NM_HSIC_PLL_CTRL2			0x20
25 #define PHY_28NM_HSIC_INT			0x28
26 
27 #define PHY_28NM_HSIC_PLL_SELLPFR_SHIFT		26
28 #define PHY_28NM_HSIC_PLL_FBDIV_SHIFT		0
29 #define PHY_28NM_HSIC_PLL_REFDIV_SHIFT		9
30 
31 #define PHY_28NM_HSIC_S2H_PU_PLL		BIT(10)
32 #define PHY_28NM_HSIC_H2S_PLL_LOCK		BIT(15)
33 #define PHY_28NM_HSIC_S2H_HSIC_EN		BIT(7)
34 #define S2H_DRV_SE0_4RESUME			BIT(14)
35 #define PHY_28NM_HSIC_H2S_IMPCAL_DONE		BIT(27)
36 
37 #define PHY_28NM_HSIC_CONNECT_INT		BIT(1)
38 #define PHY_28NM_HSIC_HS_READY_INT		BIT(2)
39 
40 struct mv_hsic_phy {
41 	struct phy		*phy;
42 	struct platform_device	*pdev;
43 	void __iomem		*base;
44 	struct clk		*clk;
45 };
46 
47 static bool wait_for_reg(void __iomem *reg, u32 mask, unsigned long timeout)
48 {
49 	timeout += jiffies;
50 	while (time_is_after_eq_jiffies(timeout)) {
51 		if ((readl(reg) & mask) == mask)
52 			return true;
53 		msleep(1);
54 	}
55 	return false;
56 }
57 
58 static int mv_hsic_phy_init(struct phy *phy)
59 {
60 	struct mv_hsic_phy *mv_phy = phy_get_drvdata(phy);
61 	struct platform_device *pdev = mv_phy->pdev;
62 	void __iomem *base = mv_phy->base;
63 
64 	clk_prepare_enable(mv_phy->clk);
65 
66 	/* Set reference clock */
67 	writel(0x1 << PHY_28NM_HSIC_PLL_SELLPFR_SHIFT |
68 		0xf0 << PHY_28NM_HSIC_PLL_FBDIV_SHIFT |
69 		0xd << PHY_28NM_HSIC_PLL_REFDIV_SHIFT,
70 		base + PHY_28NM_HSIC_PLL_CTRL01);
71 
72 	/* Turn on PLL */
73 	writel(readl(base + PHY_28NM_HSIC_PLL_CTRL2) |
74 		PHY_28NM_HSIC_S2H_PU_PLL,
75 		base + PHY_28NM_HSIC_PLL_CTRL2);
76 
77 	/* Make sure PHY PLL is locked */
78 	if (!wait_for_reg(base + PHY_28NM_HSIC_PLL_CTRL2,
79 	    PHY_28NM_HSIC_H2S_PLL_LOCK, HZ / 10)) {
80 		dev_err(&pdev->dev, "HSIC PHY PLL not locked after 100mS.");
81 		clk_disable_unprepare(mv_phy->clk);
82 		return -ETIMEDOUT;
83 	}
84 
85 	return 0;
86 }
87 
88 static int mv_hsic_phy_power_on(struct phy *phy)
89 {
90 	struct mv_hsic_phy *mv_phy = phy_get_drvdata(phy);
91 	struct platform_device *pdev = mv_phy->pdev;
92 	void __iomem *base = mv_phy->base;
93 	u32 reg;
94 
95 	reg = readl(base + PHY_28NM_HSIC_CTRL);
96 	/* Avoid SE0 state when resume for some device will take it as reset */
97 	reg &= ~S2H_DRV_SE0_4RESUME;
98 	reg |= PHY_28NM_HSIC_S2H_HSIC_EN;	/* Enable HSIC PHY */
99 	writel(reg, base + PHY_28NM_HSIC_CTRL);
100 
101 	/*
102 	 *  Calibration Timing
103 	 *		   ____________________________
104 	 *  CAL START   ___|
105 	 *			   ____________________
106 	 *  CAL_DONE    ___________|
107 	 *		   | 400us |
108 	 */
109 
110 	/* Make sure PHY Calibration is ready */
111 	if (!wait_for_reg(base + PHY_28NM_HSIC_IMPCAL_CAL,
112 	    PHY_28NM_HSIC_H2S_IMPCAL_DONE, HZ / 10)) {
113 		dev_warn(&pdev->dev, "HSIC PHY READY not set after 100mS.");
114 		return -ETIMEDOUT;
115 	}
116 
117 	/* Waiting for HSIC connect int*/
118 	if (!wait_for_reg(base + PHY_28NM_HSIC_INT,
119 	    PHY_28NM_HSIC_CONNECT_INT, HZ / 5)) {
120 		dev_warn(&pdev->dev, "HSIC wait for connect interrupt timeout.");
121 		return -ETIMEDOUT;
122 	}
123 
124 	return 0;
125 }
126 
127 static int mv_hsic_phy_power_off(struct phy *phy)
128 {
129 	struct mv_hsic_phy *mv_phy = phy_get_drvdata(phy);
130 	void __iomem *base = mv_phy->base;
131 
132 	writel(readl(base + PHY_28NM_HSIC_CTRL) & ~PHY_28NM_HSIC_S2H_HSIC_EN,
133 		base + PHY_28NM_HSIC_CTRL);
134 
135 	return 0;
136 }
137 
138 static int mv_hsic_phy_exit(struct phy *phy)
139 {
140 	struct mv_hsic_phy *mv_phy = phy_get_drvdata(phy);
141 	void __iomem *base = mv_phy->base;
142 
143 	/* Turn off PLL */
144 	writel(readl(base + PHY_28NM_HSIC_PLL_CTRL2) &
145 		~PHY_28NM_HSIC_S2H_PU_PLL,
146 		base + PHY_28NM_HSIC_PLL_CTRL2);
147 
148 	clk_disable_unprepare(mv_phy->clk);
149 	return 0;
150 }
151 
152 
153 static const struct phy_ops hsic_ops = {
154 	.init		= mv_hsic_phy_init,
155 	.power_on	= mv_hsic_phy_power_on,
156 	.power_off	= mv_hsic_phy_power_off,
157 	.exit		= mv_hsic_phy_exit,
158 	.owner		= THIS_MODULE,
159 };
160 
161 static int mv_hsic_phy_probe(struct platform_device *pdev)
162 {
163 	struct phy_provider *phy_provider;
164 	struct mv_hsic_phy *mv_phy;
165 	struct resource *r;
166 
167 	mv_phy = devm_kzalloc(&pdev->dev, sizeof(*mv_phy), GFP_KERNEL);
168 	if (!mv_phy)
169 		return -ENOMEM;
170 
171 	mv_phy->pdev = pdev;
172 
173 	mv_phy->clk = devm_clk_get(&pdev->dev, NULL);
174 	if (IS_ERR(mv_phy->clk)) {
175 		dev_err(&pdev->dev, "failed to get clock.\n");
176 		return PTR_ERR(mv_phy->clk);
177 	}
178 
179 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
180 	mv_phy->base = devm_ioremap_resource(&pdev->dev, r);
181 	if (IS_ERR(mv_phy->base))
182 		return PTR_ERR(mv_phy->base);
183 
184 	mv_phy->phy = devm_phy_create(&pdev->dev, pdev->dev.of_node, &hsic_ops);
185 	if (IS_ERR(mv_phy->phy))
186 		return PTR_ERR(mv_phy->phy);
187 
188 	phy_set_drvdata(mv_phy->phy, mv_phy);
189 
190 	phy_provider = devm_of_phy_provider_register(&pdev->dev, of_phy_simple_xlate);
191 	return PTR_ERR_OR_ZERO(phy_provider);
192 }
193 
194 static const struct of_device_id mv_hsic_phy_dt_match[] = {
195 	{ .compatible = "marvell,pxa1928-hsic-phy", },
196 	{},
197 };
198 MODULE_DEVICE_TABLE(of, mv_hsic_phy_dt_match);
199 
200 static struct platform_driver mv_hsic_phy_driver = {
201 	.probe	= mv_hsic_phy_probe,
202 	.driver = {
203 		.name   = "mv-hsic-phy",
204 		.of_match_table = of_match_ptr(mv_hsic_phy_dt_match),
205 	},
206 };
207 module_platform_driver(mv_hsic_phy_driver);
208 
209 MODULE_AUTHOR("Rob Herring <robh@kernel.org>");
210 MODULE_DESCRIPTION("Marvell HSIC phy driver");
211 MODULE_LICENSE("GPL v2");
212