1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright (c) 2018-2019 MediaTek Inc. 3 /* A library for MediaTek SGMII circuit 4 * 5 * Author: Sean Wang <sean.wang@mediatek.com> 6 * Author: Alexander Couzens <lynxis@fe80.eu> 7 * Author: Daniel Golle <daniel@makrotopia.org> 8 * 9 */ 10 11 #include <linux/mdio.h> 12 #include <linux/of.h> 13 #include <linux/pcs/pcs-mtk-lynxi.h> 14 #include <linux/phylink.h> 15 #include <linux/regmap.h> 16 17 /* SGMII subsystem config registers */ 18 /* BMCR (low 16) BMSR (high 16) */ 19 #define SGMSYS_PCS_CONTROL_1 0x0 20 #define SGMII_BMCR GENMASK(15, 0) 21 #define SGMII_BMSR GENMASK(31, 16) 22 23 #define SGMSYS_PCS_DEVICE_ID 0x4 24 #define SGMII_LYNXI_DEV_ID 0x4d544950 25 26 #define SGMSYS_PCS_ADVERTISE 0x8 27 #define SGMII_ADVERTISE GENMASK(15, 0) 28 #define SGMII_LPA GENMASK(31, 16) 29 30 #define SGMSYS_PCS_SCRATCH 0x14 31 #define SGMII_DEV_VERSION GENMASK(31, 16) 32 33 /* Register to programmable link timer, the unit in 2 * 8ns */ 34 #define SGMSYS_PCS_LINK_TIMER 0x18 35 #define SGMII_LINK_TIMER_MASK GENMASK(19, 0) 36 #define SGMII_LINK_TIMER_VAL(ns) FIELD_PREP(SGMII_LINK_TIMER_MASK, \ 37 ((ns) / 2 / 8)) 38 39 /* Register to control remote fault */ 40 #define SGMSYS_SGMII_MODE 0x20 41 #define SGMII_IF_MODE_SGMII BIT(0) 42 #define SGMII_SPEED_DUPLEX_AN BIT(1) 43 #define SGMII_SPEED_MASK GENMASK(3, 2) 44 #define SGMII_SPEED_10 FIELD_PREP(SGMII_SPEED_MASK, 0) 45 #define SGMII_SPEED_100 FIELD_PREP(SGMII_SPEED_MASK, 1) 46 #define SGMII_SPEED_1000 FIELD_PREP(SGMII_SPEED_MASK, 2) 47 #define SGMII_DUPLEX_HALF BIT(4) 48 #define SGMII_REMOTE_FAULT_DIS BIT(8) 49 50 /* Register to reset SGMII design */ 51 #define SGMSYS_RESERVED_0 0x34 52 #define SGMII_SW_RESET BIT(0) 53 54 /* Register to set SGMII speed, ANA RG_ Control Signals III */ 55 #define SGMII_PHY_SPEED_MASK GENMASK(3, 2) 56 #define SGMII_PHY_SPEED_1_25G FIELD_PREP(SGMII_PHY_SPEED_MASK, 0) 57 #define SGMII_PHY_SPEED_3_125G FIELD_PREP(SGMII_PHY_SPEED_MASK, 1) 58 59 /* Register to power up QPHY */ 60 #define SGMSYS_QPHY_PWR_STATE_CTRL 0xe8 61 #define SGMII_PHYA_PWD BIT(4) 62 63 /* Register to QPHY wrapper control */ 64 #define SGMSYS_QPHY_WRAP_CTRL 0xec 65 #define SGMII_PN_SWAP_MASK GENMASK(1, 0) 66 #define SGMII_PN_SWAP_TX_RX (BIT(0) | BIT(1)) 67 68 /* struct mtk_pcs_lynxi - This structure holds each sgmii regmap andassociated 69 * data 70 * @regmap: The register map pointing at the range used to setup 71 * SGMII modes 72 * @dev: Pointer to device owning the PCS 73 * @ana_rgc3: The offset of register ANA_RGC3 relative to regmap 74 * @interface: Currently configured interface mode 75 * @pcs: Phylink PCS structure 76 * @flags: Flags indicating hardware properties 77 */ 78 struct mtk_pcs_lynxi { 79 struct regmap *regmap; 80 u32 ana_rgc3; 81 phy_interface_t interface; 82 struct phylink_pcs pcs; 83 u32 flags; 84 }; 85 86 static struct mtk_pcs_lynxi *pcs_to_mtk_pcs_lynxi(struct phylink_pcs *pcs) 87 { 88 return container_of(pcs, struct mtk_pcs_lynxi, pcs); 89 } 90 91 static void mtk_pcs_lynxi_get_state(struct phylink_pcs *pcs, 92 struct phylink_link_state *state) 93 { 94 struct mtk_pcs_lynxi *mpcs = pcs_to_mtk_pcs_lynxi(pcs); 95 unsigned int bm, adv; 96 97 /* Read the BMSR and LPA */ 98 regmap_read(mpcs->regmap, SGMSYS_PCS_CONTROL_1, &bm); 99 regmap_read(mpcs->regmap, SGMSYS_PCS_ADVERTISE, &adv); 100 101 phylink_mii_c22_pcs_decode_state(state, FIELD_GET(SGMII_BMSR, bm), 102 FIELD_GET(SGMII_LPA, adv)); 103 } 104 105 static int mtk_pcs_lynxi_config(struct phylink_pcs *pcs, unsigned int neg_mode, 106 phy_interface_t interface, 107 const unsigned long *advertising, 108 bool permit_pause_to_mac) 109 { 110 struct mtk_pcs_lynxi *mpcs = pcs_to_mtk_pcs_lynxi(pcs); 111 bool mode_changed = false, changed; 112 unsigned int rgc3, sgm_mode, bmcr; 113 int advertise, link_timer; 114 115 advertise = phylink_mii_c22_pcs_encode_advertisement(interface, 116 advertising); 117 if (advertise < 0) 118 return advertise; 119 120 /* Clearing IF_MODE_BIT0 switches the PCS to BASE-X mode, and 121 * we assume that fixes it's speed at bitrate = line rate (in 122 * other words, 1000Mbps or 2500Mbps). 123 */ 124 if (interface == PHY_INTERFACE_MODE_SGMII) 125 sgm_mode = SGMII_IF_MODE_SGMII; 126 else 127 sgm_mode = 0; 128 129 if (neg_mode & PHYLINK_PCS_NEG_INBAND) 130 sgm_mode |= SGMII_REMOTE_FAULT_DIS; 131 132 if (neg_mode == PHYLINK_PCS_NEG_INBAND_ENABLED) { 133 if (interface == PHY_INTERFACE_MODE_SGMII) 134 sgm_mode |= SGMII_SPEED_DUPLEX_AN; 135 bmcr = BMCR_ANENABLE; 136 } else { 137 bmcr = 0; 138 } 139 140 if (mpcs->interface != interface) { 141 link_timer = phylink_get_link_timer_ns(interface); 142 if (link_timer < 0) 143 return link_timer; 144 145 /* PHYA power down */ 146 regmap_set_bits(mpcs->regmap, SGMSYS_QPHY_PWR_STATE_CTRL, 147 SGMII_PHYA_PWD); 148 149 /* Reset SGMII PCS state */ 150 regmap_set_bits(mpcs->regmap, SGMSYS_RESERVED_0, 151 SGMII_SW_RESET); 152 153 if (mpcs->flags & MTK_SGMII_FLAG_PN_SWAP) 154 regmap_update_bits(mpcs->regmap, SGMSYS_QPHY_WRAP_CTRL, 155 SGMII_PN_SWAP_MASK, 156 SGMII_PN_SWAP_TX_RX); 157 158 if (interface == PHY_INTERFACE_MODE_2500BASEX) 159 rgc3 = SGMII_PHY_SPEED_3_125G; 160 else 161 rgc3 = SGMII_PHY_SPEED_1_25G; 162 163 /* Configure the underlying interface speed */ 164 regmap_update_bits(mpcs->regmap, mpcs->ana_rgc3, 165 SGMII_PHY_SPEED_MASK, rgc3); 166 167 /* Setup the link timer */ 168 regmap_write(mpcs->regmap, SGMSYS_PCS_LINK_TIMER, 169 SGMII_LINK_TIMER_VAL(link_timer)); 170 171 mpcs->interface = interface; 172 mode_changed = true; 173 } 174 175 /* Update the advertisement, noting whether it has changed */ 176 regmap_update_bits_check(mpcs->regmap, SGMSYS_PCS_ADVERTISE, 177 SGMII_ADVERTISE, advertise, &changed); 178 179 /* Update the sgmsys mode register */ 180 regmap_update_bits(mpcs->regmap, SGMSYS_SGMII_MODE, 181 SGMII_REMOTE_FAULT_DIS | SGMII_SPEED_DUPLEX_AN | 182 SGMII_IF_MODE_SGMII, sgm_mode); 183 184 /* Update the BMCR */ 185 regmap_update_bits(mpcs->regmap, SGMSYS_PCS_CONTROL_1, 186 BMCR_ANENABLE, bmcr); 187 188 /* Release PHYA power down state 189 * Only removing bit SGMII_PHYA_PWD isn't enough. 190 * There are cases when the SGMII_PHYA_PWD register contains 0x9 which 191 * prevents SGMII from working. The SGMII still shows link but no traffic 192 * can flow. Writing 0x0 to the PHYA_PWD register fix the issue. 0x0 was 193 * taken from a good working state of the SGMII interface. 194 * Unknown how much the QPHY needs but it is racy without a sleep. 195 * Tested on mt7622 & mt7986. 196 */ 197 usleep_range(50, 100); 198 regmap_write(mpcs->regmap, SGMSYS_QPHY_PWR_STATE_CTRL, 0); 199 200 return changed || mode_changed; 201 } 202 203 static void mtk_pcs_lynxi_restart_an(struct phylink_pcs *pcs) 204 { 205 struct mtk_pcs_lynxi *mpcs = pcs_to_mtk_pcs_lynxi(pcs); 206 207 regmap_set_bits(mpcs->regmap, SGMSYS_PCS_CONTROL_1, BMCR_ANRESTART); 208 } 209 210 static void mtk_pcs_lynxi_link_up(struct phylink_pcs *pcs, 211 unsigned int neg_mode, 212 phy_interface_t interface, int speed, 213 int duplex) 214 { 215 struct mtk_pcs_lynxi *mpcs = pcs_to_mtk_pcs_lynxi(pcs); 216 unsigned int sgm_mode; 217 218 if (neg_mode != PHYLINK_PCS_NEG_INBAND_ENABLED) { 219 /* Force the speed and duplex setting */ 220 if (speed == SPEED_10) 221 sgm_mode = SGMII_SPEED_10; 222 else if (speed == SPEED_100) 223 sgm_mode = SGMII_SPEED_100; 224 else 225 sgm_mode = SGMII_SPEED_1000; 226 227 if (duplex != DUPLEX_FULL) 228 sgm_mode |= SGMII_DUPLEX_HALF; 229 230 regmap_update_bits(mpcs->regmap, SGMSYS_SGMII_MODE, 231 SGMII_DUPLEX_HALF | SGMII_SPEED_MASK, 232 sgm_mode); 233 } 234 } 235 236 static void mtk_pcs_lynxi_disable(struct phylink_pcs *pcs) 237 { 238 struct mtk_pcs_lynxi *mpcs = pcs_to_mtk_pcs_lynxi(pcs); 239 240 mpcs->interface = PHY_INTERFACE_MODE_NA; 241 } 242 243 static const struct phylink_pcs_ops mtk_pcs_lynxi_ops = { 244 .pcs_get_state = mtk_pcs_lynxi_get_state, 245 .pcs_config = mtk_pcs_lynxi_config, 246 .pcs_an_restart = mtk_pcs_lynxi_restart_an, 247 .pcs_link_up = mtk_pcs_lynxi_link_up, 248 .pcs_disable = mtk_pcs_lynxi_disable, 249 }; 250 251 struct phylink_pcs *mtk_pcs_lynxi_create(struct device *dev, 252 struct regmap *regmap, u32 ana_rgc3, 253 u32 flags) 254 { 255 struct mtk_pcs_lynxi *mpcs; 256 u32 id, ver; 257 int ret; 258 259 ret = regmap_read(regmap, SGMSYS_PCS_DEVICE_ID, &id); 260 if (ret < 0) 261 return NULL; 262 263 if (id != SGMII_LYNXI_DEV_ID) { 264 dev_err(dev, "unknown PCS device id %08x\n", id); 265 return NULL; 266 } 267 268 ret = regmap_read(regmap, SGMSYS_PCS_SCRATCH, &ver); 269 if (ret < 0) 270 return NULL; 271 272 ver = FIELD_GET(SGMII_DEV_VERSION, ver); 273 if (ver != 0x1) { 274 dev_err(dev, "unknown PCS device version %04x\n", ver); 275 return NULL; 276 } 277 278 dev_dbg(dev, "MediaTek LynxI SGMII PCS (id 0x%08x, ver 0x%04x)\n", id, 279 ver); 280 281 mpcs = kzalloc(sizeof(*mpcs), GFP_KERNEL); 282 if (!mpcs) 283 return NULL; 284 285 mpcs->ana_rgc3 = ana_rgc3; 286 mpcs->regmap = regmap; 287 mpcs->flags = flags; 288 mpcs->pcs.ops = &mtk_pcs_lynxi_ops; 289 mpcs->pcs.neg_mode = true; 290 mpcs->pcs.poll = true; 291 mpcs->interface = PHY_INTERFACE_MODE_NA; 292 293 return &mpcs->pcs; 294 } 295 EXPORT_SYMBOL(mtk_pcs_lynxi_create); 296 297 void mtk_pcs_lynxi_destroy(struct phylink_pcs *pcs) 298 { 299 if (!pcs) 300 return; 301 302 kfree(pcs_to_mtk_pcs_lynxi(pcs)); 303 } 304 EXPORT_SYMBOL(mtk_pcs_lynxi_destroy); 305 306 MODULE_DESCRIPTION("MediaTek SGMII library for LynxI"); 307 MODULE_LICENSE("GPL"); 308