aboutsummaryrefslogtreecommitdiff
path: root/drivers/net/phy/bcm84881.c
blob: 9717a1626f3fa1c4a1daea0e96858afc13472d95 (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
// SPDX-License-Identifier: GPL-2.0
// Broadcom BCM84881 NBASE-T PHY driver, as found on a SFP+ module.
// Copyright (C) 2019 Russell King, Deep Blue Solutions Ltd.
//
// Like the Marvell 88x3310, the Broadcom 84881 changes its host-side
// interface according to the operating speed between 10GBASE-R,
// 2500BASE-X and SGMII (but unlike the 88x3310, without the control
// word).
//
// This driver only supports those aspects of the PHY that I'm able to
// observe and test with the SFP+ module, which is an incomplete subset
// of what this PHY is able to support. For example, I only assume it
// supports a single lane Serdes connection, but it may be that the PHY
// is able to support more than that.
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/phy.h>

enum {
	MDIO_AN_C22 = 0xffe0,
};

static int bcm84881_wait_init(struct phy_device *phydev)
{
	int val;

	return phy_read_mmd_poll_timeout(phydev, MDIO_MMD_PMAPMD, MDIO_CTRL1,
					 val, !(val & MDIO_CTRL1_RESET),
					 100000, 2000000, false);
}

static int bcm84881_config_init(struct phy_device *phydev)
{
	switch (phydev->interface) {
	case PHY_INTERFACE_MODE_SGMII:
	case PHY_INTERFACE_MODE_2500BASEX:
	case PHY_INTERFACE_MODE_10GBASER:
		break;
	default:
		return -ENODEV;
	}
	return 0;
}

static int bcm84881_probe(struct phy_device *phydev)
{
	/* This driver requires PMAPMD and AN blocks */
	const u32 mmd_mask = MDIO_DEVS_PMAPMD | MDIO_DEVS_AN;

	if (!phydev->is_c45 ||
	    (phydev->c45_ids.devices_in_package & mmd_mask) != mmd_mask)
		return -ENODEV;

	return 0;
}

static int bcm84881_get_features(struct phy_device *phydev)
{
	int ret;

	ret = genphy_c45_pma_read_abilities(phydev);
	if (ret)
		return ret;

	/* Although the PHY sets bit 1.11.8, it does not support 10M modes */
	linkmode_clear_bit(ETHTOOL_LINK_MODE_10baseT_Half_BIT,
			   phydev->supported);
	linkmode_clear_bit(ETHTOOL_LINK_MODE_10baseT_Full_BIT,
			   phydev->supported);

	return 0;
}

static int bcm84881_config_aneg(struct phy_device *phydev)
{
	bool changed = false;
	u32 adv;
	int ret;

	/* Wait for the PHY to finish initialising, otherwise our
	 * advertisement may be overwritten.
	 */
	ret = bcm84881_wait_init(phydev);
	if (ret)
		return ret;

	/* We don't support manual MDI control */
	phydev->mdix_ctrl = ETH_TP_MDI_AUTO;

	/* disabled autoneg doesn't seem to work with this PHY */
	if (phydev->autoneg == AUTONEG_DISABLE)
		return -EINVAL;

	ret = genphy_c45_an_config_aneg(phydev);
	if (ret < 0)
		return ret;
	if (ret > 0)
		changed = true;

	adv = linkmode_adv_to_mii_ctrl1000_t(phydev->advertising);
	ret = phy_modify_mmd_changed(phydev, MDIO_MMD_AN,
				     MDIO_AN_C22 + MII_CTRL1000,
				     ADVERTISE_1000FULL | ADVERTISE_1000HALF,
				     adv);
	if (ret < 0)
		return ret;
	if (ret > 0)
		changed = true;

	return genphy_c45_check_and_restart_aneg(phydev, changed);
}

static int bcm84881_aneg_done(struct phy_device *phydev)
{
	int bmsr, val;

	val = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_STAT1);
	if (val < 0)
		return val;

	bmsr = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_AN_C22 + MII_BMSR);
	if (bmsr < 0)
		return val;

	return !!(val & MDIO_AN_STAT1_COMPLETE) &&
	       !!(bmsr & BMSR_ANEGCOMPLETE);
}

static int bcm84881_read_status(struct phy_device *phydev)
{
	unsigned int mode;
	int bmsr, val;

	val = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_CTRL1);
	if (val < 0)
		return val;

	if (val & MDIO_AN_CTRL1_RESTART) {
		phydev->link = 0;
		return 0;
	}

	val = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_STAT1);
	if (val < 0)
		return val;

	bmsr = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_AN_C22 + MII_BMSR);
	if (bmsr < 0)
		return val;

	phydev->autoneg_complete = !!(val & MDIO_AN_STAT1_COMPLETE) &&
				   !!(bmsr & BMSR_ANEGCOMPLETE);
	phydev->link = !!(val & MDIO_STAT1_LSTATUS) &&
		       !!(bmsr & BMSR_LSTATUS);
	if (phydev->autoneg == AUTONEG_ENABLE && !phydev->autoneg_complete)
		phydev->link = false;

	linkmode_zero(phydev->lp_advertising);
	phydev->speed = SPEED_UNKNOWN;
	phydev->duplex = DUPLEX_UNKNOWN;
	phydev->pause = 0;
	phydev->asym_pause = 0;
	phydev->mdix = 0;

	if (!phydev->link)
		return 0;

	if (phydev->autoneg_complete) {
		val = genphy_c45_read_lpa(phydev);
		if (val < 0)
			return val;

		val = phy_read_mmd(phydev, MDIO_MMD_AN,
				   MDIO_AN_C22 + MII_STAT1000);
		if (val < 0)
			return val;

		mii_stat1000_mod_linkmode_lpa_t(phydev->lp_advertising, val);

		if (phydev->autoneg == AUTONEG_ENABLE)
			phy_resolve_aneg_linkmode(phydev);
	}

	if (phydev->autoneg == AUTONEG_DISABLE) {
		/* disabled autoneg doesn't seem to work, so force the link
		 * down.
		 */
		phydev->link = 0;
		return 0;
	}

	/* Set the host link mode - we set the phy interface mode and
	 * the speed according to this register so that downshift works.
	 * We leave the duplex setting as per the resolution from the
	 * above.
	 */
	val = phy_read_mmd(phydev, MDIO_MMD_VEND1, 0x4011);
	mode = (val & 0x1e) >> 1;
	if (mode == 1 || mode == 2)
		phydev->interface = PHY_INTERFACE_MODE_SGMII;
	else if (mode == 3)
		phydev->interface = PHY_INTERFACE_MODE_10GBASER;
	else if (mode == 4)
		phydev->interface = PHY_INTERFACE_MODE_2500BASEX;
	switch (mode & 7) {
	case 1:
		phydev->speed = SPEED_100;
		break;
	case 2:
		phydev->speed = SPEED_1000;
		break;
	case 3:
		phydev->speed = SPEED_10000;
		break;
	case 4:
		phydev->speed = SPEED_2500;
		break;
	case 5:
		phydev->speed = SPEED_5000;
		break;
	}

	return genphy_c45_read_mdix(phydev);
}

static struct phy_driver bcm84881_drivers[] = {
	{
		.phy_id		= 0xae025150,
		.phy_id_mask	= 0xfffffff0,
		.name		= "Broadcom BCM84881",
		.config_init	= bcm84881_config_init,
		.probe		= bcm84881_probe,
		.get_features	= bcm84881_get_features,
		.config_aneg	= bcm84881_config_aneg,
		.aneg_done	= bcm84881_aneg_done,
		.read_status	= bcm84881_read_status,
	},
};

module_phy_driver(bcm84881_drivers);

/* FIXME: module auto-loading for Clause 45 PHYs seems non-functional */
static struct mdio_device_id __maybe_unused bcm84881_tbl[] = {
	{ 0xae025150, 0xfffffff0 },
	{ },
};
MODULE_AUTHOR("Russell King");
MODULE_DESCRIPTION("Broadcom BCM84881 PHY driver");
MODULE_DEVICE_TABLE(mdio, bcm84881_tbl);
MODULE_LICENSE("GPL");