summaryrefslogtreecommitdiff
path: root/drivers/phy/broadcom/phy-bcm-cygnus-pcie.c
blob: cc29b08e49ebcb5399c9969cd1cb05fdaefea561 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
// SPDX-License-Identifier: GPL-2.0-only
// Copyright (C) 2015 Broadcom Corporation

#include <linux/delay.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>

#define PCIE_CFG_OFFSET         0x00
#define PCIE1_PHY_IDDQ_SHIFT    10
#define PCIE0_PHY_IDDQ_SHIFT    2

enum cygnus_pcie_phy_id {
	CYGNUS_PHY_PCIE0 = 0,
	CYGNUS_PHY_PCIE1,
	MAX_NUM_PHYS,
};

struct cygnus_pcie_phy_core;

/**
 * struct cygnus_pcie_phy - Cygnus PCIe PHY device
 * @core: pointer to the Cygnus PCIe PHY core control
 * @id: internal ID to identify the Cygnus PCIe PHY
 * @phy: pointer to the kernel PHY device
 */
struct cygnus_pcie_phy {
	struct cygnus_pcie_phy_core *core;
	enum cygnus_pcie_phy_id id;
	struct phy *phy;
};

/**
 * struct cygnus_pcie_phy_core - Cygnus PCIe PHY core control
 * @dev: pointer to device
 * @base: base register
 * @lock: mutex to protect access to individual PHYs
 * @phys: pointer to Cygnus PHY device
 */
struct cygnus_pcie_phy_core {
	struct device *dev;
	void __iomem *base;
	struct mutex lock;
	struct cygnus_pcie_phy phys[MAX_NUM_PHYS];
};

static int cygnus_pcie_power_config(struct cygnus_pcie_phy *phy, bool enable)
{
	struct cygnus_pcie_phy_core *core = phy->core;
	unsigned shift;
	u32 val;

	mutex_lock(&core->lock);

	switch (phy->id) {
	case CYGNUS_PHY_PCIE0:
		shift = PCIE0_PHY_IDDQ_SHIFT;
		break;

	case CYGNUS_PHY_PCIE1:
		shift = PCIE1_PHY_IDDQ_SHIFT;
		break;

	default:
		mutex_unlock(&core->lock);
		dev_err(core->dev, "PCIe PHY %d invalid\n", phy->id);
		return -EINVAL;
	}

	if (enable) {
		val = readl(core->base + PCIE_CFG_OFFSET);
		val &= ~BIT(shift);
		writel(val, core->base + PCIE_CFG_OFFSET);
		/*
		 * Wait 50 ms for the PCIe Serdes to stabilize after the analog
		 * front end is brought up
		 */
		msleep(50);
	} else {
		val = readl(core->base + PCIE_CFG_OFFSET);
		val |= BIT(shift);
		writel(val, core->base + PCIE_CFG_OFFSET);
	}

	mutex_unlock(&core->lock);
	dev_dbg(core->dev, "PCIe PHY %d %s\n", phy->id,
		enable ? "enabled" : "disabled");
	return 0;
}

static int cygnus_pcie_phy_power_on(struct phy *p)
{
	struct cygnus_pcie_phy *phy = phy_get_drvdata(p);

	return cygnus_pcie_power_config(phy, true);
}

static int cygnus_pcie_phy_power_off(struct phy *p)
{
	struct cygnus_pcie_phy *phy = phy_get_drvdata(p);

	return cygnus_pcie_power_config(phy, false);
}

static const struct phy_ops cygnus_pcie_phy_ops = {
	.power_on = cygnus_pcie_phy_power_on,
	.power_off = cygnus_pcie_phy_power_off,
	.owner = THIS_MODULE,
};

static int cygnus_pcie_phy_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct device_node *node = dev->of_node, *child;
	struct cygnus_pcie_phy_core *core;
	struct phy_provider *provider;
	unsigned cnt = 0;
	int ret;

	if (of_get_child_count(node) == 0) {
		dev_err(dev, "PHY no child node\n");
		return -ENODEV;
	}

	core = devm_kzalloc(dev, sizeof(*core), GFP_KERNEL);
	if (!core)
		return -ENOMEM;

	core->dev = dev;

	core->base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(core->base))
		return PTR_ERR(core->base);

	mutex_init(&core->lock);

	for_each_available_child_of_node(node, child) {
		unsigned int id;
		struct cygnus_pcie_phy *p;

		if (of_property_read_u32(child, "reg", &id)) {
			dev_err(dev, "missing reg property for %pOFn\n",
				child);
			ret = -EINVAL;
			goto put_child;
		}

		if (id >= MAX_NUM_PHYS) {
			dev_err(dev, "invalid PHY id: %u\n", id);
			ret = -EINVAL;
			goto put_child;
		}

		if (core->phys[id].phy) {
			dev_err(dev, "duplicated PHY id: %u\n", id);
			ret = -EINVAL;
			goto put_child;
		}

		p = &core->phys[id];
		p->phy = devm_phy_create(dev, child, &cygnus_pcie_phy_ops);
		if (IS_ERR(p->phy)) {
			dev_err(dev, "failed to create PHY\n");
			ret = PTR_ERR(p->phy);
			goto put_child;
		}

		p->core = core;
		p->id = id;
		phy_set_drvdata(p->phy, p);
		cnt++;
	}

	dev_set_drvdata(dev, core);

	provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
	if (IS_ERR(provider)) {
		dev_err(dev, "failed to register PHY provider\n");
		return PTR_ERR(provider);
	}

	dev_dbg(dev, "registered %u PCIe PHY(s)\n", cnt);

	return 0;
put_child:
	of_node_put(child);
	return ret;
}

static const struct of_device_id cygnus_pcie_phy_match_table[] = {
	{ .compatible = "brcm,cygnus-pcie-phy" },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, cygnus_pcie_phy_match_table);

static struct platform_driver cygnus_pcie_phy_driver = {
	.driver = {
		.name = "cygnus-pcie-phy",
		.of_match_table = cygnus_pcie_phy_match_table,
	},
	.probe = cygnus_pcie_phy_probe,
};
module_platform_driver(cygnus_pcie_phy_driver);

MODULE_AUTHOR("Ray Jui <rjui@broadcom.com>");
MODULE_DESCRIPTION("Broadcom Cygnus PCIe PHY driver");
MODULE_LICENSE("GPL v2");