1 /*
2  * Marvell Berlin SATA PHY driver
3  *
4  * Copyright (C) 2014 Marvell Technology Group Ltd.
5  *
6  * Antoine Ténart <antoine.tenart@free-electrons.com>
7  *
8  * This file is licensed under the terms of the GNU General Public
9  * License version 2. This program is licensed "as is" without any
10  * warranty of any kind, whether express or implied.
11  */
12 
13 #include <linux/clk.h>
14 #include <linux/module.h>
15 #include <linux/phy/phy.h>
16 #include <linux/io.h>
17 #include <linux/platform_device.h>
18 
19 #define HOST_VSA_ADDR		0x0
20 #define HOST_VSA_DATA		0x4
21 #define PORT_SCR_CTL		0x2c
22 #define PORT_VSR_ADDR		0x78
23 #define PORT_VSR_DATA		0x7c
24 
25 #define CONTROL_REGISTER	0x0
26 #define MBUS_SIZE_CONTROL	0x4
27 
28 #define POWER_DOWN_PHY0			BIT(6)
29 #define POWER_DOWN_PHY1			BIT(14)
30 #define MBUS_WRITE_REQUEST_SIZE_128	(BIT(2) << 16)
31 #define MBUS_READ_REQUEST_SIZE_128	(BIT(2) << 19)
32 
33 #define BG2_PHY_BASE		0x080
34 #define BG2Q_PHY_BASE		0x200
35 
36 /* register 0x01 */
37 #define REF_FREF_SEL_25		BIT(0)
38 #define PHY_MODE_SATA		(0x0 << 5)
39 
40 /* register 0x02 */
41 #define USE_MAX_PLL_RATE	BIT(12)
42 
43 /* register 0x23 */
44 #define DATA_BIT_WIDTH_10	(0x0 << 10)
45 #define DATA_BIT_WIDTH_20	(0x1 << 10)
46 #define DATA_BIT_WIDTH_40	(0x2 << 10)
47 
48 /* register 0x25 */
49 #define PHY_GEN_MAX_1_5		(0x0 << 10)
50 #define PHY_GEN_MAX_3_0		(0x1 << 10)
51 #define PHY_GEN_MAX_6_0		(0x2 << 10)
52 
53 struct phy_berlin_desc {
54 	struct phy	*phy;
55 	u32		power_bit;
56 	unsigned	index;
57 };
58 
59 struct phy_berlin_priv {
60 	void __iomem		*base;
61 	spinlock_t		lock;
62 	struct clk		*clk;
63 	struct phy_berlin_desc	**phys;
64 	unsigned		nphys;
65 	u32			phy_base;
66 };
67 
68 static inline void phy_berlin_sata_reg_setbits(void __iomem *ctrl_reg,
69 			       u32 phy_base, u32 reg, u32 mask, u32 val)
70 {
71 	u32 regval;
72 
73 	/* select register */
74 	writel(phy_base + reg, ctrl_reg + PORT_VSR_ADDR);
75 
76 	/* set bits */
77 	regval = readl(ctrl_reg + PORT_VSR_DATA);
78 	regval &= ~mask;
79 	regval |= val;
80 	writel(regval, ctrl_reg + PORT_VSR_DATA);
81 }
82 
83 static int phy_berlin_sata_power_on(struct phy *phy)
84 {
85 	struct phy_berlin_desc *desc = phy_get_drvdata(phy);
86 	struct phy_berlin_priv *priv = dev_get_drvdata(phy->dev.parent);
87 	void __iomem *ctrl_reg = priv->base + 0x60 + (desc->index * 0x80);
88 	u32 regval;
89 
90 	clk_prepare_enable(priv->clk);
91 
92 	spin_lock(&priv->lock);
93 
94 	/* Power on PHY */
95 	writel(CONTROL_REGISTER, priv->base + HOST_VSA_ADDR);
96 	regval = readl(priv->base + HOST_VSA_DATA);
97 	regval &= ~desc->power_bit;
98 	writel(regval, priv->base + HOST_VSA_DATA);
99 
100 	/* Configure MBus */
101 	writel(MBUS_SIZE_CONTROL, priv->base + HOST_VSA_ADDR);
102 	regval = readl(priv->base + HOST_VSA_DATA);
103 	regval |= MBUS_WRITE_REQUEST_SIZE_128 | MBUS_READ_REQUEST_SIZE_128;
104 	writel(regval, priv->base + HOST_VSA_DATA);
105 
106 	/* set PHY mode and ref freq to 25 MHz */
107 	phy_berlin_sata_reg_setbits(ctrl_reg, priv->phy_base, 0x01,
108 				    0x00ff, REF_FREF_SEL_25 | PHY_MODE_SATA);
109 
110 	/* set PHY up to 6 Gbps */
111 	phy_berlin_sata_reg_setbits(ctrl_reg, priv->phy_base, 0x25,
112 				    0x0c00, PHY_GEN_MAX_6_0);
113 
114 	/* set 40 bits width */
115 	phy_berlin_sata_reg_setbits(ctrl_reg, priv->phy_base, 0x23,
116 				    0x0c00, DATA_BIT_WIDTH_40);
117 
118 	/* use max pll rate */
119 	phy_berlin_sata_reg_setbits(ctrl_reg, priv->phy_base, 0x02,
120 				    0x0000, USE_MAX_PLL_RATE);
121 
122 	/* set Gen3 controller speed */
123 	regval = readl(ctrl_reg + PORT_SCR_CTL);
124 	regval &= ~GENMASK(7, 4);
125 	regval |= 0x30;
126 	writel(regval, ctrl_reg + PORT_SCR_CTL);
127 
128 	spin_unlock(&priv->lock);
129 
130 	clk_disable_unprepare(priv->clk);
131 
132 	return 0;
133 }
134 
135 static int phy_berlin_sata_power_off(struct phy *phy)
136 {
137 	struct phy_berlin_desc *desc = phy_get_drvdata(phy);
138 	struct phy_berlin_priv *priv = dev_get_drvdata(phy->dev.parent);
139 	u32 regval;
140 
141 	clk_prepare_enable(priv->clk);
142 
143 	spin_lock(&priv->lock);
144 
145 	/* Power down PHY */
146 	writel(CONTROL_REGISTER, priv->base + HOST_VSA_ADDR);
147 	regval = readl(priv->base + HOST_VSA_DATA);
148 	regval |= desc->power_bit;
149 	writel(regval, priv->base + HOST_VSA_DATA);
150 
151 	spin_unlock(&priv->lock);
152 
153 	clk_disable_unprepare(priv->clk);
154 
155 	return 0;
156 }
157 
158 static struct phy *phy_berlin_sata_phy_xlate(struct device *dev,
159 					     struct of_phandle_args *args)
160 {
161 	struct phy_berlin_priv *priv = dev_get_drvdata(dev);
162 	int i;
163 
164 	if (WARN_ON(args->args[0] >= priv->nphys))
165 		return ERR_PTR(-ENODEV);
166 
167 	for (i = 0; i < priv->nphys; i++) {
168 		if (priv->phys[i]->index == args->args[0])
169 			break;
170 	}
171 
172 	if (i == priv->nphys)
173 		return ERR_PTR(-ENODEV);
174 
175 	return priv->phys[i]->phy;
176 }
177 
178 static const struct phy_ops phy_berlin_sata_ops = {
179 	.power_on	= phy_berlin_sata_power_on,
180 	.power_off	= phy_berlin_sata_power_off,
181 	.owner		= THIS_MODULE,
182 };
183 
184 static u32 phy_berlin_power_down_bits[] = {
185 	POWER_DOWN_PHY0,
186 	POWER_DOWN_PHY1,
187 };
188 
189 static int phy_berlin_sata_probe(struct platform_device *pdev)
190 {
191 	struct device *dev = &pdev->dev;
192 	struct device_node *child;
193 	struct phy *phy;
194 	struct phy_provider *phy_provider;
195 	struct phy_berlin_priv *priv;
196 	struct resource *res;
197 	int ret, i = 0;
198 	u32 phy_id;
199 
200 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
201 	if (!priv)
202 		return -ENOMEM;
203 
204 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
205 	if (!res)
206 		return -EINVAL;
207 
208 	priv->base = devm_ioremap(dev, res->start, resource_size(res));
209 	if (!priv->base)
210 		return -ENOMEM;
211 
212 	priv->clk = devm_clk_get(dev, NULL);
213 	if (IS_ERR(priv->clk))
214 		return PTR_ERR(priv->clk);
215 
216 	priv->nphys = of_get_child_count(dev->of_node);
217 	if (priv->nphys == 0)
218 		return -ENODEV;
219 
220 	priv->phys = devm_kcalloc(dev, priv->nphys, sizeof(*priv->phys),
221 				  GFP_KERNEL);
222 	if (!priv->phys)
223 		return -ENOMEM;
224 
225 	if (of_device_is_compatible(dev->of_node, "marvell,berlin2-sata-phy"))
226 		priv->phy_base = BG2_PHY_BASE;
227 	else
228 		priv->phy_base = BG2Q_PHY_BASE;
229 
230 	dev_set_drvdata(dev, priv);
231 	spin_lock_init(&priv->lock);
232 
233 	for_each_available_child_of_node(dev->of_node, child) {
234 		struct phy_berlin_desc *phy_desc;
235 
236 		if (of_property_read_u32(child, "reg", &phy_id)) {
237 			dev_err(dev, "missing reg property in node %s\n",
238 				child->name);
239 			ret = -EINVAL;
240 			goto put_child;
241 		}
242 
243 		if (phy_id >= ARRAY_SIZE(phy_berlin_power_down_bits)) {
244 			dev_err(dev, "invalid reg in node %s\n", child->name);
245 			ret = -EINVAL;
246 			goto put_child;
247 		}
248 
249 		phy_desc = devm_kzalloc(dev, sizeof(*phy_desc), GFP_KERNEL);
250 		if (!phy_desc) {
251 			ret = -ENOMEM;
252 			goto put_child;
253 		}
254 
255 		phy = devm_phy_create(dev, NULL, &phy_berlin_sata_ops);
256 		if (IS_ERR(phy)) {
257 			dev_err(dev, "failed to create PHY %d\n", phy_id);
258 			ret = PTR_ERR(phy);
259 			goto put_child;
260 		}
261 
262 		phy_desc->phy = phy;
263 		phy_desc->power_bit = phy_berlin_power_down_bits[phy_id];
264 		phy_desc->index = phy_id;
265 		phy_set_drvdata(phy, phy_desc);
266 
267 		priv->phys[i++] = phy_desc;
268 
269 		/* Make sure the PHY is off */
270 		phy_berlin_sata_power_off(phy);
271 	}
272 
273 	phy_provider =
274 		devm_of_phy_provider_register(dev, phy_berlin_sata_phy_xlate);
275 	return PTR_ERR_OR_ZERO(phy_provider);
276 put_child:
277 	of_node_put(child);
278 	return ret;
279 }
280 
281 static const struct of_device_id phy_berlin_sata_of_match[] = {
282 	{ .compatible = "marvell,berlin2-sata-phy" },
283 	{ .compatible = "marvell,berlin2q-sata-phy" },
284 	{ },
285 };
286 MODULE_DEVICE_TABLE(of, phy_berlin_sata_of_match);
287 
288 static struct platform_driver phy_berlin_sata_driver = {
289 	.probe	= phy_berlin_sata_probe,
290 	.driver	= {
291 		.name		= "phy-berlin-sata",
292 		.of_match_table	= phy_berlin_sata_of_match,
293 	},
294 };
295 module_platform_driver(phy_berlin_sata_driver);
296 
297 MODULE_DESCRIPTION("Marvell Berlin SATA PHY driver");
298 MODULE_AUTHOR("Antoine Ténart <antoine.tenart@free-electrons.com>");
299 MODULE_LICENSE("GPL v2");
300