summaryrefslogtreecommitdiffstats
path: root/drivers/net/phy/meson-gxl.c
blob: b03bcf2c388aee4fa2b9d0bfa22f573e2689d824 (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
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
/*
 * Amlogic Meson GXL Internal PHY Driver
 *
 * Copyright (C) 2015 Amlogic, Inc. All rights reserved.
 * Copyright (C) 2016 BayLibre, SAS. All rights reserved.
 * Author: Neil Armstrong <narmstrong@baylibre.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mii.h>
#include <linux/ethtool.h>
#include <linux/phy.h>
#include <linux/netdevice.h>
#include <linux/bitfield.h>

#define TSTCNTL		20
#define  TSTCNTL_READ		BIT(15)
#define  TSTCNTL_WRITE		BIT(14)
#define  TSTCNTL_REG_BANK_SEL	GENMASK(12, 11)
#define  TSTCNTL_TEST_MODE	BIT(10)
#define  TSTCNTL_READ_ADDRESS	GENMASK(9, 5)
#define  TSTCNTL_WRITE_ADDRESS	GENMASK(4, 0)
#define TSTREAD1	21
#define TSTWRITE	23
#define INTSRC_FLAG	29
#define  INTSRC_ANEG_PR		BIT(1)
#define  INTSRC_PARALLEL_FAULT	BIT(2)
#define  INTSRC_ANEG_LP_ACK	BIT(3)
#define  INTSRC_LINK_DOWN	BIT(4)
#define  INTSRC_REMOTE_FAULT	BIT(5)
#define  INTSRC_ANEG_COMPLETE	BIT(6)
#define INTSRC_MASK	30

#define BANK_ANALOG_DSP		0
#define BANK_WOL		1
#define BANK_BIST		3

/* WOL Registers */
#define LPI_STATUS	0xc
#define  LPI_STATUS_RSV12	BIT(12)

/* BIST Registers */
#define FR_PLL_CONTROL	0x1b
#define FR_PLL_DIV0	0x1c
#define FR_PLL_DIV1	0x1d

static int meson_gxl_open_banks(struct phy_device *phydev)
{
	int ret;

	/* Enable Analog and DSP register Bank access by
	 * toggling TSTCNTL_TEST_MODE bit in the TSTCNTL register
	 */
	ret = phy_write(phydev, TSTCNTL, 0);
	if (ret)
		return ret;
	ret = phy_write(phydev, TSTCNTL, TSTCNTL_TEST_MODE);
	if (ret)
		return ret;
	ret = phy_write(phydev, TSTCNTL, 0);
	if (ret)
		return ret;
	return phy_write(phydev, TSTCNTL, TSTCNTL_TEST_MODE);
}

static void meson_gxl_close_banks(struct phy_device *phydev)
{
	phy_write(phydev, TSTCNTL, 0);
}

static int meson_gxl_read_reg(struct phy_device *phydev,
			      unsigned int bank, unsigned int reg)
{
	int ret;

	ret = meson_gxl_open_banks(phydev);
	if (ret)
		goto out;

	ret = phy_write(phydev, TSTCNTL, TSTCNTL_READ |
			FIELD_PREP(TSTCNTL_REG_BANK_SEL, bank) |
			TSTCNTL_TEST_MODE |
			FIELD_PREP(TSTCNTL_READ_ADDRESS, reg));
	if (ret)
		goto out;

	ret = phy_read(phydev, TSTREAD1);
out:
	/* Close the bank access on our way out */
	meson_gxl_close_banks(phydev);
	return ret;
}

static int meson_gxl_write_reg(struct phy_device *phydev,
			       unsigned int bank, unsigned int reg,
			       uint16_t value)
{
	int ret;

	ret = meson_gxl_open_banks(phydev);
	if (ret)
		goto out;

	ret = phy_write(phydev, TSTWRITE, value);
	if (ret)
		goto out;

	ret = phy_write(phydev, TSTCNTL, TSTCNTL_WRITE |
			FIELD_PREP(TSTCNTL_REG_BANK_SEL, bank) |
			TSTCNTL_TEST_MODE |
			FIELD_PREP(TSTCNTL_WRITE_ADDRESS, reg));

out:
	/* Close the bank access on our way out */
	meson_gxl_close_banks(phydev);
	return ret;
}

static int meson_gxl_config_init(struct phy_device *phydev)
{
	int ret;

	/* Enable fractional PLL */
	ret = meson_gxl_write_reg(phydev, BANK_BIST, FR_PLL_CONTROL, 0x5);
	if (ret)
		return ret;

	/* Program fraction FR_PLL_DIV1 */
	ret = meson_gxl_write_reg(phydev, BANK_BIST, FR_PLL_DIV1, 0x029a);
	if (ret)
		return ret;

	/* Program fraction FR_PLL_DIV1 */
	ret = meson_gxl_write_reg(phydev, BANK_BIST, FR_PLL_DIV0, 0xaaaa);
	if (ret)
		return ret;

	return genphy_config_init(phydev);
}

/* This function is provided to cope with the possible failures of this phy
 * during aneg process. When aneg fails, the PHY reports that aneg is done
 * but the value found in MII_LPA is wrong:
 *  - Early failures: MII_LPA is just 0x0001. if MII_EXPANSION reports that
 *    the link partner (LP) supports aneg but the LP never acked our base
 *    code word, it is likely that we never sent it to begin with.
 *  - Late failures: MII_LPA is filled with a value which seems to make sense
 *    but it actually is not what the LP is advertising. It seems that we
 *    can detect this using a magic bit in the WOL bank (reg 12 - bit 12).
 *    If this particular bit is not set when aneg is reported being done,
 *    it means MII_LPA is likely to be wrong.
 *
 * In both case, forcing a restart of the aneg process solve the problem.
 * When this failure happens, the first retry is usually successful but,
 * in some cases, it may take up to 6 retries to get a decent result
 */
static int meson_gxl_read_status(struct phy_device *phydev)
{
	int ret, wol, lpa, exp;

	if (phydev->autoneg == AUTONEG_ENABLE) {
		ret = genphy_aneg_done(phydev);
		if (ret < 0)
			return ret;
		else if (!ret)
			goto read_status_continue;

		/* Aneg is done, let's check everything is fine */
		wol = meson_gxl_read_reg(phydev, BANK_WOL, LPI_STATUS);
		if (wol < 0)
			return wol;

		lpa = phy_read(phydev, MII_LPA);
		if (lpa < 0)
			return lpa;

		exp = phy_read(phydev, MII_EXPANSION);
		if (exp < 0)
			return exp;

		if (!(wol & LPI_STATUS_RSV12) ||
		    ((exp & EXPANSION_NWAY) && !(lpa & LPA_LPACK))) {
			/* Looks like aneg failed after all */
			phydev_dbg(phydev, "LPA corruption - aneg restart\n");
			return genphy_restart_aneg(phydev);
		}
	}

read_status_continue:
	return genphy_read_status(phydev);
}

static int meson_gxl_ack_interrupt(struct phy_device *phydev)
{
	int ret = phy_read(phydev, INTSRC_FLAG);

	return ret < 0 ? ret : 0;
}

static int meson_gxl_config_intr(struct phy_device *phydev)
{
	u16 val;

	if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
		val = INTSRC_ANEG_PR
			| INTSRC_PARALLEL_FAULT
			| INTSRC_ANEG_LP_ACK
			| INTSRC_LINK_DOWN
			| INTSRC_REMOTE_FAULT
			| INTSRC_ANEG_COMPLETE;
	} else {
		val = 0;
	}

	return phy_write(phydev, INTSRC_MASK, val);
}

static struct phy_driver meson_gxl_phy[] = {
	{
		.phy_id		= 0x01814400,
		.phy_id_mask	= 0xfffffff0,
		.name		= "Meson GXL Internal PHY",
		.features	= PHY_BASIC_FEATURES,
		.flags		= PHY_IS_INTERNAL,
		.config_init	= meson_gxl_config_init,
		.aneg_done      = genphy_aneg_done,
		.read_status	= meson_gxl_read_status,
		.ack_interrupt	= meson_gxl_ack_interrupt,
		.config_intr	= meson_gxl_config_intr,
		.suspend        = genphy_suspend,
		.resume         = genphy_resume,
	},
};

static struct mdio_device_id __maybe_unused meson_gxl_tbl[] = {
	{ 0x01814400, 0xfffffff0 },
	{ }
};

module_phy_driver(meson_gxl_phy);

MODULE_DEVICE_TABLE(mdio, meson_gxl_tbl);

MODULE_DESCRIPTION("Amlogic Meson GXL Internal PHY driver");
MODULE_AUTHOR("Baoqi wang");
MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
MODULE_LICENSE("GPL");