1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2019 MediaTek Inc.
4  * Author: Stanley Chu <stanley.chu@mediatek.com>
5  */
6 
7 #include <linux/clk.h>
8 #include <linux/delay.h>
9 #include <linux/io.h>
10 #include <linux/module.h>
11 #include <linux/phy/phy.h>
12 #include <linux/platform_device.h>
13 
14 /* mphy register and offsets */
15 #define MP_GLB_DIG_8C               0x008C
16 #define FRC_PLL_ISO_EN              BIT(8)
17 #define PLL_ISO_EN                  BIT(9)
18 #define FRC_FRC_PWR_ON              BIT(10)
19 #define PLL_PWR_ON                  BIT(11)
20 
21 #define MP_LN_DIG_RX_9C             0xA09C
22 #define FSM_DIFZ_FRC                BIT(18)
23 
24 #define MP_LN_DIG_RX_AC             0xA0AC
25 #define FRC_RX_SQ_EN                BIT(0)
26 #define RX_SQ_EN                    BIT(1)
27 
28 #define MP_LN_RX_44                 0xB044
29 #define FRC_CDR_PWR_ON              BIT(17)
30 #define CDR_PWR_ON                  BIT(18)
31 #define FRC_CDR_ISO_EN              BIT(19)
32 #define CDR_ISO_EN                  BIT(20)
33 
34 struct ufs_mtk_phy {
35 	struct device *dev;
36 	void __iomem *mmio;
37 	struct clk *mp_clk;
38 	struct clk *unipro_clk;
39 };
40 
41 static inline u32 mphy_readl(struct ufs_mtk_phy *phy, u32 reg)
42 {
43 	return readl(phy->mmio + reg);
44 }
45 
46 static inline void mphy_writel(struct ufs_mtk_phy *phy, u32 val, u32 reg)
47 {
48 	writel(val, phy->mmio + reg);
49 }
50 
51 static void mphy_set_bit(struct ufs_mtk_phy *phy, u32 reg, u32 bit)
52 {
53 	u32 val;
54 
55 	val = mphy_readl(phy, reg);
56 	val |= bit;
57 	mphy_writel(phy, val, reg);
58 }
59 
60 static void mphy_clr_bit(struct ufs_mtk_phy *phy, u32 reg, u32 bit)
61 {
62 	u32 val;
63 
64 	val = mphy_readl(phy, reg);
65 	val &= ~bit;
66 	mphy_writel(phy, val, reg);
67 }
68 
69 static struct ufs_mtk_phy *get_ufs_mtk_phy(struct phy *generic_phy)
70 {
71 	return (struct ufs_mtk_phy *)phy_get_drvdata(generic_phy);
72 }
73 
74 static int ufs_mtk_phy_clk_init(struct ufs_mtk_phy *phy)
75 {
76 	struct device *dev = phy->dev;
77 
78 	phy->unipro_clk = devm_clk_get(dev, "unipro");
79 	if (IS_ERR(phy->unipro_clk)) {
80 		dev_err(dev, "failed to get clock: unipro");
81 		return PTR_ERR(phy->unipro_clk);
82 	}
83 
84 	phy->mp_clk = devm_clk_get(dev, "mp");
85 	if (IS_ERR(phy->mp_clk)) {
86 		dev_err(dev, "failed to get clock: mp");
87 		return PTR_ERR(phy->mp_clk);
88 	}
89 
90 	return 0;
91 }
92 
93 static void ufs_mtk_phy_set_active(struct ufs_mtk_phy *phy)
94 {
95 	/* release DA_MP_PLL_PWR_ON */
96 	mphy_set_bit(phy, MP_GLB_DIG_8C, PLL_PWR_ON);
97 	mphy_clr_bit(phy, MP_GLB_DIG_8C, FRC_FRC_PWR_ON);
98 
99 	/* release DA_MP_PLL_ISO_EN */
100 	mphy_clr_bit(phy, MP_GLB_DIG_8C, PLL_ISO_EN);
101 	mphy_clr_bit(phy, MP_GLB_DIG_8C, FRC_PLL_ISO_EN);
102 
103 	/* release DA_MP_CDR_PWR_ON */
104 	mphy_set_bit(phy, MP_LN_RX_44, CDR_PWR_ON);
105 	mphy_clr_bit(phy, MP_LN_RX_44, FRC_CDR_PWR_ON);
106 
107 	/* release DA_MP_CDR_ISO_EN */
108 	mphy_clr_bit(phy, MP_LN_RX_44, CDR_ISO_EN);
109 	mphy_clr_bit(phy, MP_LN_RX_44, FRC_CDR_ISO_EN);
110 
111 	/* release DA_MP_RX0_SQ_EN */
112 	mphy_set_bit(phy, MP_LN_DIG_RX_AC, RX_SQ_EN);
113 	mphy_clr_bit(phy, MP_LN_DIG_RX_AC, FRC_RX_SQ_EN);
114 
115 	/* delay 1us to wait DIFZ stable */
116 	udelay(1);
117 
118 	/* release DIFZ */
119 	mphy_clr_bit(phy, MP_LN_DIG_RX_9C, FSM_DIFZ_FRC);
120 }
121 
122 static void ufs_mtk_phy_set_deep_hibern(struct ufs_mtk_phy *phy)
123 {
124 	/* force DIFZ */
125 	mphy_set_bit(phy, MP_LN_DIG_RX_9C, FSM_DIFZ_FRC);
126 
127 	/* force DA_MP_RX0_SQ_EN */
128 	mphy_set_bit(phy, MP_LN_DIG_RX_AC, FRC_RX_SQ_EN);
129 	mphy_clr_bit(phy, MP_LN_DIG_RX_AC, RX_SQ_EN);
130 
131 	/* force DA_MP_CDR_ISO_EN */
132 	mphy_set_bit(phy, MP_LN_RX_44, FRC_CDR_ISO_EN);
133 	mphy_set_bit(phy, MP_LN_RX_44, CDR_ISO_EN);
134 
135 	/* force DA_MP_CDR_PWR_ON */
136 	mphy_set_bit(phy, MP_LN_RX_44, FRC_CDR_PWR_ON);
137 	mphy_clr_bit(phy, MP_LN_RX_44, CDR_PWR_ON);
138 
139 	/* force DA_MP_PLL_ISO_EN */
140 	mphy_set_bit(phy, MP_GLB_DIG_8C, FRC_PLL_ISO_EN);
141 	mphy_set_bit(phy, MP_GLB_DIG_8C, PLL_ISO_EN);
142 
143 	/* force DA_MP_PLL_PWR_ON */
144 	mphy_set_bit(phy, MP_GLB_DIG_8C, FRC_FRC_PWR_ON);
145 	mphy_clr_bit(phy, MP_GLB_DIG_8C, PLL_PWR_ON);
146 }
147 
148 static int ufs_mtk_phy_power_on(struct phy *generic_phy)
149 {
150 	struct ufs_mtk_phy *phy = get_ufs_mtk_phy(generic_phy);
151 	int ret;
152 
153 	ret = clk_prepare_enable(phy->unipro_clk);
154 	if (ret) {
155 		dev_err(phy->dev, "unipro_clk enable failed %d\n", ret);
156 		goto out;
157 	}
158 
159 	ret = clk_prepare_enable(phy->mp_clk);
160 	if (ret) {
161 		dev_err(phy->dev, "mp_clk enable failed %d\n", ret);
162 		goto out_unprepare_unipro_clk;
163 	}
164 
165 	ufs_mtk_phy_set_active(phy);
166 
167 	return 0;
168 
169 out_unprepare_unipro_clk:
170 	clk_disable_unprepare(phy->unipro_clk);
171 out:
172 	return ret;
173 }
174 
175 static int ufs_mtk_phy_power_off(struct phy *generic_phy)
176 {
177 	struct ufs_mtk_phy *phy = get_ufs_mtk_phy(generic_phy);
178 
179 	ufs_mtk_phy_set_deep_hibern(phy);
180 
181 	clk_disable_unprepare(phy->unipro_clk);
182 	clk_disable_unprepare(phy->mp_clk);
183 
184 	return 0;
185 }
186 
187 static const struct phy_ops ufs_mtk_phy_ops = {
188 	.power_on       = ufs_mtk_phy_power_on,
189 	.power_off      = ufs_mtk_phy_power_off,
190 	.owner          = THIS_MODULE,
191 };
192 
193 static int ufs_mtk_phy_probe(struct platform_device *pdev)
194 {
195 	struct device *dev = &pdev->dev;
196 	struct phy *generic_phy;
197 	struct phy_provider *phy_provider;
198 	struct ufs_mtk_phy *phy;
199 	int ret;
200 
201 	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
202 	if (!phy)
203 		return -ENOMEM;
204 
205 	phy->mmio = devm_platform_ioremap_resource(pdev, 0);
206 	if (IS_ERR(phy->mmio))
207 		return PTR_ERR(phy->mmio);
208 
209 	phy->dev = dev;
210 
211 	ret = ufs_mtk_phy_clk_init(phy);
212 	if (ret)
213 		return ret;
214 
215 	generic_phy = devm_phy_create(dev, NULL, &ufs_mtk_phy_ops);
216 	if (IS_ERR(generic_phy))
217 		return PTR_ERR(generic_phy);
218 
219 	phy_set_drvdata(generic_phy, phy);
220 
221 	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
222 
223 	return PTR_ERR_OR_ZERO(phy_provider);
224 }
225 
226 static const struct of_device_id ufs_mtk_phy_of_match[] = {
227 	{.compatible = "mediatek,mt8183-ufsphy"},
228 	{},
229 };
230 MODULE_DEVICE_TABLE(of, ufs_mtk_phy_of_match);
231 
232 static struct platform_driver ufs_mtk_phy_driver = {
233 	.probe = ufs_mtk_phy_probe,
234 	.driver = {
235 		.of_match_table = ufs_mtk_phy_of_match,
236 		.name = "ufs_mtk_phy",
237 	},
238 };
239 module_platform_driver(ufs_mtk_phy_driver);
240 
241 MODULE_DESCRIPTION("Universal Flash Storage (UFS) MediaTek MPHY");
242 MODULE_AUTHOR("Stanley Chu <stanley.chu@mediatek.com>");
243 MODULE_LICENSE("GPL v2");
244