summaryrefslogtreecommitdiff
path: root/drivers/net/mdio/mdio-aspeed.c
blob: c2170650415cdbd9d6076fe12e0014c33e40be15 (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
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
// SPDX-License-Identifier: GPL-2.0-or-later
/* Copyright (C) 2019 IBM Corp. */

#include <linux/bitfield.h>
#include <linux/delay.h>
#include <linux/reset.h>
#include <linux/iopoll.h>
#include <linux/mdio.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_mdio.h>
#include <linux/phy.h>
#include <linux/platform_device.h>

#define DRV_NAME "mdio-aspeed"

#define ASPEED_MDIO_CTRL		0x0
#define   ASPEED_MDIO_CTRL_FIRE		BIT(31)
#define   ASPEED_MDIO_CTRL_ST		BIT(28)
#define     ASPEED_MDIO_CTRL_ST_C45	0
#define     ASPEED_MDIO_CTRL_ST_C22	1
#define   ASPEED_MDIO_CTRL_OP		GENMASK(27, 26)
#define     MDIO_C22_OP_WRITE		0b01
#define     MDIO_C22_OP_READ		0b10
#define     MDIO_C45_OP_ADDR		0b00
#define     MDIO_C45_OP_WRITE		0b01
#define     MDIO_C45_OP_PREAD		0b10
#define     MDIO_C45_OP_READ		0b11
#define   ASPEED_MDIO_CTRL_PHYAD	GENMASK(25, 21)
#define   ASPEED_MDIO_CTRL_REGAD	GENMASK(20, 16)
#define   ASPEED_MDIO_CTRL_MIIWDATA	GENMASK(15, 0)

#define ASPEED_MDIO_DATA		0x4
#define   ASPEED_MDIO_DATA_MDC_THRES	GENMASK(31, 24)
#define   ASPEED_MDIO_DATA_MDIO_EDGE	BIT(23)
#define   ASPEED_MDIO_DATA_MDIO_LATCH	GENMASK(22, 20)
#define   ASPEED_MDIO_DATA_IDLE		BIT(16)
#define   ASPEED_MDIO_DATA_MIIRDATA	GENMASK(15, 0)

#define ASPEED_MDIO_INTERVAL_US		100
#define ASPEED_MDIO_TIMEOUT_US		(ASPEED_MDIO_INTERVAL_US * 10)

struct aspeed_mdio {
	void __iomem *base;
	struct reset_control *reset;
};

static int aspeed_mdio_op(struct mii_bus *bus, u8 st, u8 op, u8 phyad, u8 regad,
			  u16 data)
{
	struct aspeed_mdio *ctx = bus->priv;
	u32 ctrl;

	dev_dbg(&bus->dev, "%s: st: %u op: %u, phyad: %u, regad: %u, data: %u\n",
		__func__, st, op, phyad, regad, data);

	ctrl = ASPEED_MDIO_CTRL_FIRE
		| FIELD_PREP(ASPEED_MDIO_CTRL_ST, st)
		| FIELD_PREP(ASPEED_MDIO_CTRL_OP, op)
		| FIELD_PREP(ASPEED_MDIO_CTRL_PHYAD, phyad)
		| FIELD_PREP(ASPEED_MDIO_CTRL_REGAD, regad)
		| FIELD_PREP(ASPEED_MDIO_DATA_MIIRDATA, data);

	iowrite32(ctrl, ctx->base + ASPEED_MDIO_CTRL);

	return readl_poll_timeout(ctx->base + ASPEED_MDIO_CTRL, ctrl,
				!(ctrl & ASPEED_MDIO_CTRL_FIRE),
				ASPEED_MDIO_INTERVAL_US,
				ASPEED_MDIO_TIMEOUT_US);
}

static int aspeed_mdio_get_data(struct mii_bus *bus)
{
	struct aspeed_mdio *ctx = bus->priv;
	u32 data;
	int rc;

	rc = readl_poll_timeout(ctx->base + ASPEED_MDIO_DATA, data,
				data & ASPEED_MDIO_DATA_IDLE,
				ASPEED_MDIO_INTERVAL_US,
				ASPEED_MDIO_TIMEOUT_US);
	if (rc < 0)
		return rc;

	return FIELD_GET(ASPEED_MDIO_DATA_MIIRDATA, data);
}

static int aspeed_mdio_read_c22(struct mii_bus *bus, int addr, int regnum)
{
	int rc;

	rc = aspeed_mdio_op(bus, ASPEED_MDIO_CTRL_ST_C22, MDIO_C22_OP_READ,
			    addr, regnum, 0);
	if (rc < 0)
		return rc;

	return aspeed_mdio_get_data(bus);
}

static int aspeed_mdio_write_c22(struct mii_bus *bus, int addr, int regnum,
				 u16 val)
{
	return aspeed_mdio_op(bus, ASPEED_MDIO_CTRL_ST_C22, MDIO_C22_OP_WRITE,
			      addr, regnum, val);
}

static int aspeed_mdio_read_c45(struct mii_bus *bus, int addr, int devad,
				int regnum)
{
	int rc;

	rc = aspeed_mdio_op(bus, ASPEED_MDIO_CTRL_ST_C45, MDIO_C45_OP_ADDR,
			    addr, devad, regnum);
	if (rc < 0)
		return rc;

	rc = aspeed_mdio_op(bus, ASPEED_MDIO_CTRL_ST_C45, MDIO_C45_OP_READ,
			    addr, devad, 0);
	if (rc < 0)
		return rc;

	return aspeed_mdio_get_data(bus);
}

static int aspeed_mdio_write_c45(struct mii_bus *bus, int addr, int devad,
				 int regnum, u16 val)
{
	int rc;

	rc = aspeed_mdio_op(bus, ASPEED_MDIO_CTRL_ST_C45, MDIO_C45_OP_ADDR,
			    addr, devad, regnum);
	if (rc < 0)
		return rc;

	return aspeed_mdio_op(bus, ASPEED_MDIO_CTRL_ST_C45, MDIO_C45_OP_WRITE,
			      addr, devad, val);
}

static int aspeed_mdio_probe(struct platform_device *pdev)
{
	struct aspeed_mdio *ctx;
	struct mii_bus *bus;
	int rc;

	bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*ctx));
	if (!bus)
		return -ENOMEM;

	ctx = bus->priv;
	ctx->base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(ctx->base))
		return PTR_ERR(ctx->base);

	ctx->reset = devm_reset_control_get_optional_shared(&pdev->dev, NULL);
	if (IS_ERR(ctx->reset))
		return PTR_ERR(ctx->reset);

	reset_control_deassert(ctx->reset);

	bus->name = DRV_NAME;
	snprintf(bus->id, MII_BUS_ID_SIZE, "%s%d", pdev->name, pdev->id);
	bus->parent = &pdev->dev;
	bus->read = aspeed_mdio_read_c22;
	bus->write = aspeed_mdio_write_c22;
	bus->read_c45 = aspeed_mdio_read_c45;
	bus->write_c45 = aspeed_mdio_write_c45;

	rc = of_mdiobus_register(bus, pdev->dev.of_node);
	if (rc) {
		dev_err(&pdev->dev, "Cannot register MDIO bus!\n");
		reset_control_assert(ctx->reset);
		return rc;
	}

	platform_set_drvdata(pdev, bus);

	return 0;
}

static void aspeed_mdio_remove(struct platform_device *pdev)
{
	struct mii_bus *bus = (struct mii_bus *)platform_get_drvdata(pdev);
	struct aspeed_mdio *ctx = bus->priv;

	reset_control_assert(ctx->reset);
	mdiobus_unregister(bus);
}

static const struct of_device_id aspeed_mdio_of_match[] = {
	{ .compatible = "aspeed,ast2600-mdio", },
	{ },
};
MODULE_DEVICE_TABLE(of, aspeed_mdio_of_match);

static struct platform_driver aspeed_mdio_driver = {
	.driver = {
		.name = DRV_NAME,
		.of_match_table = aspeed_mdio_of_match,
	},
	.probe = aspeed_mdio_probe,
	.remove_new = aspeed_mdio_remove,
};

module_platform_driver(aspeed_mdio_driver);

MODULE_AUTHOR("Andrew Jeffery <andrew@aj.id.au>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("ASPEED MDIO bus controller");