summaryrefslogtreecommitdiffstats
path: root/drivers/phy/tegra/phy-tegra194-p2u.c
blob: f49b417c9eb605b42dce5910fb29d5331bdfb4ce (plain)
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
// SPDX-License-Identifier: GPL-2.0+
/*
 * P2U (PIPE to UPHY) driver for Tegra T194 SoC
 *
 * Copyright (C) 2019-2022 NVIDIA Corporation.
 *
 * Author: Vidya Sagar <vidyas@nvidia.com>
 */

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

#define P2U_CONTROL_CMN			0x74
#define P2U_CONTROL_CMN_ENABLE_L2_EXIT_RATE_CHANGE		BIT(13)
#define P2U_CONTROL_CMN_SKP_SIZE_PROTECTION_EN			BIT(20)

#define P2U_PERIODIC_EQ_CTRL_GEN3	0xc0
#define P2U_PERIODIC_EQ_CTRL_GEN3_PERIODIC_EQ_EN		BIT(0)
#define P2U_PERIODIC_EQ_CTRL_GEN3_INIT_PRESET_EQ_TRAIN_EN	BIT(1)
#define P2U_PERIODIC_EQ_CTRL_GEN4	0xc4
#define P2U_PERIODIC_EQ_CTRL_GEN4_INIT_PRESET_EQ_TRAIN_EN	BIT(1)

#define P2U_RX_DEBOUNCE_TIME				0xa4
#define P2U_RX_DEBOUNCE_TIME_DEBOUNCE_TIMER_MASK	0xffff
#define P2U_RX_DEBOUNCE_TIME_DEBOUNCE_TIMER_VAL		160

#define P2U_DIR_SEARCH_CTRL				0xd4
#define P2U_DIR_SEARCH_CTRL_GEN4_FINE_GRAIN_SEARCH_TWICE	BIT(18)

struct tegra_p2u_of_data {
	bool one_dir_search;
};

struct tegra_p2u {
	void __iomem *base;
	bool skip_sz_protection_en; /* Needed to support two retimers */
	struct tegra_p2u_of_data *of_data;
};

static inline void p2u_writel(struct tegra_p2u *phy, const u32 value,
			      const u32 reg)
{
	writel_relaxed(value, phy->base + reg);
}

static inline u32 p2u_readl(struct tegra_p2u *phy, const u32 reg)
{
	return readl_relaxed(phy->base + reg);
}

static int tegra_p2u_power_on(struct phy *x)
{
	struct tegra_p2u *phy = phy_get_drvdata(x);
	u32 val;

	if (phy->skip_sz_protection_en) {
		val = p2u_readl(phy, P2U_CONTROL_CMN);
		val |= P2U_CONTROL_CMN_SKP_SIZE_PROTECTION_EN;
		p2u_writel(phy, val, P2U_CONTROL_CMN);
	}

	val = p2u_readl(phy, P2U_PERIODIC_EQ_CTRL_GEN3);
	val &= ~P2U_PERIODIC_EQ_CTRL_GEN3_PERIODIC_EQ_EN;
	val |= P2U_PERIODIC_EQ_CTRL_GEN3_INIT_PRESET_EQ_TRAIN_EN;
	p2u_writel(phy, val, P2U_PERIODIC_EQ_CTRL_GEN3);

	val = p2u_readl(phy, P2U_PERIODIC_EQ_CTRL_GEN4);
	val |= P2U_PERIODIC_EQ_CTRL_GEN4_INIT_PRESET_EQ_TRAIN_EN;
	p2u_writel(phy, val, P2U_PERIODIC_EQ_CTRL_GEN4);

	val = p2u_readl(phy, P2U_RX_DEBOUNCE_TIME);
	val &= ~P2U_RX_DEBOUNCE_TIME_DEBOUNCE_TIMER_MASK;
	val |= P2U_RX_DEBOUNCE_TIME_DEBOUNCE_TIMER_VAL;
	p2u_writel(phy, val, P2U_RX_DEBOUNCE_TIME);

	if (phy->of_data->one_dir_search) {
		val = p2u_readl(phy, P2U_DIR_SEARCH_CTRL);
		val &= ~P2U_DIR_SEARCH_CTRL_GEN4_FINE_GRAIN_SEARCH_TWICE;
		p2u_writel(phy, val, P2U_DIR_SEARCH_CTRL);
	}

	return 0;
}

static int tegra_p2u_calibrate(struct phy *x)
{
	struct tegra_p2u *phy = phy_get_drvdata(x);
	u32 val;

	val = p2u_readl(phy, P2U_CONTROL_CMN);
	val |= P2U_CONTROL_CMN_ENABLE_L2_EXIT_RATE_CHANGE;
	p2u_writel(phy, val, P2U_CONTROL_CMN);

	return 0;
}

static const struct phy_ops ops = {
	.power_on = tegra_p2u_power_on,
	.calibrate = tegra_p2u_calibrate,
	.owner = THIS_MODULE,
};

static int tegra_p2u_probe(struct platform_device *pdev)
{
	struct phy_provider *phy_provider;
	struct device *dev = &pdev->dev;
	struct phy *generic_phy;
	struct tegra_p2u *phy;

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

	phy->of_data =
		(struct tegra_p2u_of_data *)of_device_get_match_data(dev);
	if (!phy->of_data)
		return -EINVAL;

	phy->base = devm_platform_ioremap_resource_byname(pdev, "ctl");
	if (IS_ERR(phy->base))
		return PTR_ERR(phy->base);

	phy->skip_sz_protection_en =
		of_property_read_bool(dev->of_node,
				      "nvidia,skip-sz-protect-en");

	platform_set_drvdata(pdev, phy);

	generic_phy = devm_phy_create(dev, NULL, &ops);
	if (IS_ERR(generic_phy))
		return PTR_ERR(generic_phy);

	phy_set_drvdata(generic_phy, phy);

	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
	if (IS_ERR(phy_provider))
		return PTR_ERR(phy_provider);

	return 0;
}

static const struct tegra_p2u_of_data tegra194_p2u_of_data = {
	.one_dir_search = false,
};

static const struct tegra_p2u_of_data tegra234_p2u_of_data = {
	.one_dir_search = true,
};

static const struct of_device_id tegra_p2u_id_table[] = {
	{
		.compatible = "nvidia,tegra194-p2u",
		.data = &tegra194_p2u_of_data,
	},
	{
		.compatible = "nvidia,tegra234-p2u",
		.data = &tegra234_p2u_of_data,
	},
	{}
};
MODULE_DEVICE_TABLE(of, tegra_p2u_id_table);

static struct platform_driver tegra_p2u_driver = {
	.probe = tegra_p2u_probe,
	.driver = {
		.name = "tegra194-p2u",
		.of_match_table = tegra_p2u_id_table,
	},
};
module_platform_driver(tegra_p2u_driver);

MODULE_AUTHOR("Vidya Sagar <vidyas@nvidia.com>");
MODULE_DESCRIPTION("NVIDIA Tegra194 PIPE2UPHY PHY driver");
MODULE_LICENSE("GPL v2");