1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2018-2019 MediaTek Inc.
3
4 /* A library for MediaTek SGMII circuit
5 *
6 * Author: Sean Wang <sean.wang@mediatek.com>
7 *
8 */
9
10 #include <linux/mfd/syscon.h>
11 #include <linux/of.h>
12 #include <linux/phylink.h>
13 #include <linux/regmap.h>
14
15 #include "mtk_eth_soc.h"
16
pcs_to_mtk_pcs(struct phylink_pcs * pcs)17 static struct mtk_pcs *pcs_to_mtk_pcs(struct phylink_pcs *pcs)
18 {
19 return container_of(pcs, struct mtk_pcs, pcs);
20 }
21
mtk_pcs_get_state(struct phylink_pcs * pcs,struct phylink_link_state * state)22 static void mtk_pcs_get_state(struct phylink_pcs *pcs,
23 struct phylink_link_state *state)
24 {
25 struct mtk_pcs *mpcs = pcs_to_mtk_pcs(pcs);
26 unsigned int bm, adv;
27
28 /* Read the BMSR and LPA */
29 regmap_read(mpcs->regmap, SGMSYS_PCS_CONTROL_1, &bm);
30 regmap_read(mpcs->regmap, SGMSYS_PCS_ADVERTISE, &adv);
31
32 phylink_mii_c22_pcs_decode_state(state, FIELD_GET(SGMII_BMSR, bm),
33 FIELD_GET(SGMII_LPA, adv));
34 }
35
mtk_pcs_config(struct phylink_pcs * pcs,unsigned int mode,phy_interface_t interface,const unsigned long * advertising,bool permit_pause_to_mac)36 static int mtk_pcs_config(struct phylink_pcs *pcs, unsigned int mode,
37 phy_interface_t interface,
38 const unsigned long *advertising,
39 bool permit_pause_to_mac)
40 {
41 struct mtk_pcs *mpcs = pcs_to_mtk_pcs(pcs);
42 unsigned int rgc3, sgm_mode, bmcr;
43 int advertise, link_timer;
44 bool changed, use_an;
45
46 advertise = phylink_mii_c22_pcs_encode_advertisement(interface,
47 advertising);
48 if (advertise < 0)
49 return advertise;
50
51 link_timer = phylink_get_link_timer_ns(interface);
52 if (link_timer < 0)
53 return link_timer;
54
55 /* Clearing IF_MODE_BIT0 switches the PCS to BASE-X mode, and
56 * we assume that fixes it's speed at bitrate = line rate (in
57 * other words, 1000Mbps or 2500Mbps).
58 */
59 if (interface == PHY_INTERFACE_MODE_SGMII) {
60 sgm_mode = SGMII_IF_MODE_SGMII;
61 if (phylink_autoneg_inband(mode)) {
62 sgm_mode |= SGMII_REMOTE_FAULT_DIS |
63 SGMII_SPEED_DUPLEX_AN;
64 use_an = true;
65 } else {
66 use_an = false;
67 }
68 } else if (phylink_autoneg_inband(mode)) {
69 /* 1000base-X or 2500base-X autoneg */
70 sgm_mode = SGMII_REMOTE_FAULT_DIS;
71 use_an = linkmode_test_bit(ETHTOOL_LINK_MODE_Autoneg_BIT,
72 advertising);
73 } else {
74 /* 1000base-X or 2500base-X without autoneg */
75 sgm_mode = 0;
76 use_an = false;
77 }
78
79 if (use_an) {
80 /* FIXME: Do we need to set AN_RESTART here? */
81 bmcr = SGMII_AN_RESTART | SGMII_AN_ENABLE;
82 } else {
83 bmcr = 0;
84 }
85
86 if (mpcs->interface != interface) {
87 /* PHYA power down */
88 regmap_update_bits(mpcs->regmap, SGMSYS_QPHY_PWR_STATE_CTRL,
89 SGMII_PHYA_PWD, SGMII_PHYA_PWD);
90
91 if (interface == PHY_INTERFACE_MODE_2500BASEX)
92 rgc3 = RG_PHY_SPEED_3_125G;
93 else
94 rgc3 = 0;
95
96 /* Configure the underlying interface speed */
97 regmap_update_bits(mpcs->regmap, mpcs->ana_rgc3,
98 RG_PHY_SPEED_3_125G, rgc3);
99
100 mpcs->interface = interface;
101 }
102
103 /* Update the advertisement, noting whether it has changed */
104 regmap_update_bits_check(mpcs->regmap, SGMSYS_PCS_ADVERTISE,
105 SGMII_ADVERTISE, advertise, &changed);
106
107 /* Setup the link timer and QPHY power up inside SGMIISYS */
108 regmap_write(mpcs->regmap, SGMSYS_PCS_LINK_TIMER, link_timer / 2 / 8);
109
110 /* Update the sgmsys mode register */
111 regmap_update_bits(mpcs->regmap, SGMSYS_SGMII_MODE,
112 SGMII_REMOTE_FAULT_DIS | SGMII_SPEED_DUPLEX_AN |
113 SGMII_IF_MODE_SGMII, sgm_mode);
114
115 /* Update the BMCR */
116 regmap_update_bits(mpcs->regmap, SGMSYS_PCS_CONTROL_1,
117 SGMII_AN_RESTART | SGMII_AN_ENABLE, bmcr);
118
119 /* Release PHYA power down state
120 * Only removing bit SGMII_PHYA_PWD isn't enough.
121 * There are cases when the SGMII_PHYA_PWD register contains 0x9 which
122 * prevents SGMII from working. The SGMII still shows link but no traffic
123 * can flow. Writing 0x0 to the PHYA_PWD register fix the issue. 0x0 was
124 * taken from a good working state of the SGMII interface.
125 * Unknown how much the QPHY needs but it is racy without a sleep.
126 * Tested on mt7622 & mt7986.
127 */
128 usleep_range(50, 100);
129 regmap_write(mpcs->regmap, SGMSYS_QPHY_PWR_STATE_CTRL, 0);
130
131 return changed;
132 }
133
mtk_pcs_restart_an(struct phylink_pcs * pcs)134 static void mtk_pcs_restart_an(struct phylink_pcs *pcs)
135 {
136 struct mtk_pcs *mpcs = pcs_to_mtk_pcs(pcs);
137
138 regmap_update_bits(mpcs->regmap, SGMSYS_PCS_CONTROL_1,
139 SGMII_AN_RESTART, SGMII_AN_RESTART);
140 }
141
mtk_pcs_link_up(struct phylink_pcs * pcs,unsigned int mode,phy_interface_t interface,int speed,int duplex)142 static void mtk_pcs_link_up(struct phylink_pcs *pcs, unsigned int mode,
143 phy_interface_t interface, int speed, int duplex)
144 {
145 struct mtk_pcs *mpcs = pcs_to_mtk_pcs(pcs);
146 unsigned int sgm_mode;
147
148 if (!phylink_autoneg_inband(mode)) {
149 /* Force the speed and duplex setting */
150 if (speed == SPEED_10)
151 sgm_mode = SGMII_SPEED_10;
152 else if (speed == SPEED_100)
153 sgm_mode = SGMII_SPEED_100;
154 else
155 sgm_mode = SGMII_SPEED_1000;
156
157 if (duplex != DUPLEX_FULL)
158 sgm_mode |= SGMII_DUPLEX_HALF;
159
160 regmap_update_bits(mpcs->regmap, SGMSYS_SGMII_MODE,
161 SGMII_DUPLEX_HALF | SGMII_SPEED_MASK,
162 sgm_mode);
163 }
164 }
165
166 static const struct phylink_pcs_ops mtk_pcs_ops = {
167 .pcs_get_state = mtk_pcs_get_state,
168 .pcs_config = mtk_pcs_config,
169 .pcs_an_restart = mtk_pcs_restart_an,
170 .pcs_link_up = mtk_pcs_link_up,
171 };
172
mtk_sgmii_init(struct mtk_sgmii * ss,struct device_node * r,u32 ana_rgc3)173 int mtk_sgmii_init(struct mtk_sgmii *ss, struct device_node *r, u32 ana_rgc3)
174 {
175 struct device_node *np;
176 int i;
177
178 for (i = 0; i < MTK_MAX_DEVS; i++) {
179 np = of_parse_phandle(r, "mediatek,sgmiisys", i);
180 if (!np)
181 break;
182
183 ss->pcs[i].ana_rgc3 = ana_rgc3;
184 ss->pcs[i].regmap = syscon_node_to_regmap(np);
185 of_node_put(np);
186 if (IS_ERR(ss->pcs[i].regmap))
187 return PTR_ERR(ss->pcs[i].regmap);
188
189 ss->pcs[i].pcs.ops = &mtk_pcs_ops;
190 ss->pcs[i].pcs.poll = true;
191 ss->pcs[i].interface = PHY_INTERFACE_MODE_NA;
192 }
193
194 return 0;
195 }
196
mtk_sgmii_select_pcs(struct mtk_sgmii * ss,int id)197 struct phylink_pcs *mtk_sgmii_select_pcs(struct mtk_sgmii *ss, int id)
198 {
199 if (!ss->pcs[id].regmap)
200 return NULL;
201
202 return &ss->pcs[id].pcs;
203 }
204