drivers/net/dsa/b53/b53_serdes.c

   1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
   2 /*
   3  * Northstar Plus switch SerDes/SGMII PHY main logic
   4  *
   5  * Copyright (C) 2018 Florian Fainelli <f.fainelli@gmail.com>
   6  */
   7
   8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   9
  10 #include <linux/delay.h>
  11 #include <linux/kernel.h>
  12 #include <linux/phy.h>
  13 #include <linux/phylink.h>
  14 #include <net/dsa.h>
  15
  16 #include "b53_priv.h"
  17 #include "b53_serdes.h"
  18 #include "b53_regs.h"
  19
  20 static inline struct b53_pcs *pcs_to_b53_pcs(struct phylink_pcs *pcs)
  21 {
  22         return container_of(pcs, struct b53_pcs, pcs);
  23 }
  24
  25 static void b53_serdes_write_blk(struct b53_device *dev, u8 offset, u16 block,
  26                                  u16 value)
  27 {
  28         b53_write16(dev, B53_SERDES_PAGE, B53_SERDES_BLKADDR, block);
  29         b53_write16(dev, B53_SERDES_PAGE, offset, value);
  30 }
  31
  32 static u16 b53_serdes_read_blk(struct b53_device *dev, u8 offset, u16 block)
  33 {
  34         u16 value;
  35
  36         b53_write16(dev, B53_SERDES_PAGE, B53_SERDES_BLKADDR, block);
  37         b53_read16(dev, B53_SERDES_PAGE, offset, &value);
  38
  39         return value;
  40 }
  41
  42 static void b53_serdes_set_lane(struct b53_device *dev, u8 lane)
  43 {
  44         if (dev->serdes_lane == lane)
  45                 return;
  46
  47         WARN_ON(lane > 1);
  48
  49         b53_serdes_write_blk(dev, B53_SERDES_LANE,
  50                              SERDES_XGXSBLK0_BLOCKADDRESS, lane);
  51         dev->serdes_lane = lane;
  52 }
  53
  54 static void b53_serdes_write(struct b53_device *dev, u8 lane,
  55                              u8 offset, u16 block, u16 value)
  56 {
  57         b53_serdes_set_lane(dev, lane);
  58         b53_serdes_write_blk(dev, offset, block, value);
  59 }
  60
  61 static u16 b53_serdes_read(struct b53_device *dev, u8 lane,
  62                            u8 offset, u16 block)
  63 {
  64         b53_serdes_set_lane(dev, lane);
  65         return b53_serdes_read_blk(dev, offset, block);
  66 }
  67
  68 static int b53_serdes_config(struct phylink_pcs *pcs, unsigned int neg_mode,
  69                              phy_interface_t interface,
  70                              const unsigned long *advertising,
  71                              bool permit_pause_to_mac)
  72 {
  73         struct b53_device *dev = pcs_to_b53_pcs(pcs)->dev;
  74         u8 lane = pcs_to_b53_pcs(pcs)->lane;
  75         u16 reg;
  76
  77         reg = b53_serdes_read(dev, lane, B53_SERDES_DIGITAL_CONTROL(1),
  78                               SERDES_DIGITAL_BLK);
  79         if (interface == PHY_INTERFACE_MODE_1000BASEX)
  80                 reg |= FIBER_MODE_1000X;
  81         else
  82                 reg &= ~FIBER_MODE_1000X;
  83         b53_serdes_write(dev, lane, B53_SERDES_DIGITAL_CONTROL(1),
  84                          SERDES_DIGITAL_BLK, reg);
  85
  86         return 0;
  87 }
  88
  89 static void b53_serdes_an_restart(struct phylink_pcs *pcs)
  90 {
  91         struct b53_device *dev = pcs_to_b53_pcs(pcs)->dev;
  92         u8 lane = pcs_to_b53_pcs(pcs)->lane;
  93         u16 reg;
  94
  95         reg = b53_serdes_read(dev, lane, B53_SERDES_MII_REG(MII_BMCR),
  96                               SERDES_MII_BLK);
  97         reg |= BMCR_ANRESTART;
  98         b53_serdes_write(dev, lane, B53_SERDES_MII_REG(MII_BMCR),
  99                          SERDES_MII_BLK, reg);
 100 }
 101
 102 static void b53_serdes_get_state(struct phylink_pcs *pcs,
 103                                   struct phylink_link_state *state)
 104 {
 105         struct b53_device *dev = pcs_to_b53_pcs(pcs)->dev;
 106         u8 lane = pcs_to_b53_pcs(pcs)->lane;
 107         u16 dig, bmsr;
 108
 109         dig = b53_serdes_read(dev, lane, B53_SERDES_DIGITAL_STATUS,
 110                               SERDES_DIGITAL_BLK);
 111         bmsr = b53_serdes_read(dev, lane, B53_SERDES_MII_REG(MII_BMSR),
 112                                SERDES_MII_BLK);
 113
 114         switch ((dig >> SPEED_STATUS_SHIFT) & SPEED_STATUS_MASK) {
 115         case SPEED_STATUS_10:
 116                 state->speed = SPEED_10;
 117                 break;
 118         case SPEED_STATUS_100:
 119                 state->speed = SPEED_100;
 120                 break;
 121         case SPEED_STATUS_1000:
 122                 state->speed = SPEED_1000;
 123                 break;
 124         default:
 125         case SPEED_STATUS_2500:
 126                 state->speed = SPEED_2500;
 127                 break;
 128         }
 129
 130         state->duplex = dig & DUPLEX_STATUS ? DUPLEX_FULL : DUPLEX_HALF;
 131         state->an_complete = !!(bmsr & BMSR_ANEGCOMPLETE);
 132         state->link = !!(dig & LINK_STATUS);
 133         if (dig & PAUSE_RESOLUTION_RX_SIDE)
 134                 state->pause |= MLO_PAUSE_RX;
 135         if (dig & PAUSE_RESOLUTION_TX_SIDE)
 136                 state->pause |= MLO_PAUSE_TX;
 137 }
 138
 139 void b53_serdes_link_set(struct b53_device *dev, int port, unsigned int mode,
 140                          phy_interface_t interface, bool link_up)
 141 {
 142         u8 lane = b53_serdes_map_lane(dev, port);
 143         u16 reg;
 144
 145         if (lane == B53_INVALID_LANE)
 146                 return;
 147
 148         reg = b53_serdes_read(dev, lane, B53_SERDES_MII_REG(MII_BMCR),
 149                               SERDES_MII_BLK);
 150         if (link_up)
 151                 reg &= ~BMCR_PDOWN;
 152         else
 153                 reg |= BMCR_PDOWN;
 154         b53_serdes_write(dev, lane, B53_SERDES_MII_REG(MII_BMCR),
 155                          SERDES_MII_BLK, reg);
 156 }
 157 EXPORT_SYMBOL(b53_serdes_link_set);
 158
 159 static const struct phylink_pcs_ops b53_pcs_ops = {
 160         .pcs_get_state = b53_serdes_get_state,
 161         .pcs_config = b53_serdes_config,
 162         .pcs_an_restart = b53_serdes_an_restart,
 163 };
 164
 165 void b53_serdes_phylink_get_caps(struct b53_device *dev, int port,
 166                                  struct phylink_config *config)
 167 {
 168         u8 lane = b53_serdes_map_lane(dev, port);
 169
 170         if (lane == B53_INVALID_LANE)
 171                 return;
 172
 173         switch (lane) {
 174         case 0:
 175                 /* It appears lane 0 supports 2500base-X and 1000base-X */
 176                 __set_bit(PHY_INTERFACE_MODE_2500BASEX,
 177                           config->supported_interfaces);
 178                 config->mac_capabilities |= MAC_2500FD;
 179                 fallthrough;
 180         case 1:
 181                 /* It appears lane 1 only supports 1000base-X and SGMII */
 182                 __set_bit(PHY_INTERFACE_MODE_1000BASEX,
 183                           config->supported_interfaces);
 184                 __set_bit(PHY_INTERFACE_MODE_SGMII,
 185                           config->supported_interfaces);
 186                 config->mac_capabilities |= MAC_1000FD;
 187                 break;
 188         default:
 189                 break;
 190         }
 191 }
 192 EXPORT_SYMBOL(b53_serdes_phylink_get_caps);
 193
 194 struct phylink_pcs *b53_serdes_phylink_mac_select_pcs(struct b53_device *dev,
 195                                                       int port,
 196                                                       phy_interface_t interface)
 197 {
 198         u8 lane = b53_serdes_map_lane(dev, port);
 199
 200         if (lane == B53_INVALID_LANE || lane >= B53_N_PCS ||
 201             !dev->pcs[lane].dev)
 202                 return NULL;
 203
 204         if (!phy_interface_mode_is_8023z(interface) &&
 205             interface != PHY_INTERFACE_MODE_SGMII)
 206                 return NULL;
 207
 208         return &dev->pcs[lane].pcs;
 209 }
 210 EXPORT_SYMBOL(b53_serdes_phylink_mac_select_pcs);
 211
 212 int b53_serdes_init(struct b53_device *dev, int port)
 213 {
 214         u8 lane = b53_serdes_map_lane(dev, port);
 215         struct b53_pcs *pcs;
 216         u16 id0, msb, lsb;
 217
 218         if (lane == B53_INVALID_LANE)
 219                 return -EINVAL;
 220
 221         id0 = b53_serdes_read(dev, lane, B53_SERDES_ID0, SERDES_ID0);
 222         msb = b53_serdes_read(dev, lane, B53_SERDES_MII_REG(MII_PHYSID1),
 223                               SERDES_MII_BLK);
 224         lsb = b53_serdes_read(dev, lane, B53_SERDES_MII_REG(MII_PHYSID2),
 225                               SERDES_MII_BLK);
 226         if (id0 == 0 || id0 == 0xffff) {
 227                 dev_err(dev->dev, "SerDes not initialized, check settings\n");
 228                 return -ENODEV;
 229         }
 230
 231         dev_info(dev->dev,
 232                  "SerDes lane %d, model: %d, rev %c%d (OUI: 0x%08x)\n",
 233                  lane, id0 & SERDES_ID0_MODEL_MASK,
 234                  (id0 >> SERDES_ID0_REV_LETTER_SHIFT) + 0x41,
 235                  (id0 >> SERDES_ID0_REV_NUM_SHIFT) & SERDES_ID0_REV_NUM_MASK,
 236                  (u32)msb << 16 | lsb);
 237
 238         pcs = &dev->pcs[lane];
 239         pcs->dev = dev;
 240         pcs->lane = lane;
 241         pcs->pcs.ops = &b53_pcs_ops;
 242         pcs->pcs.neg_mode = true;
 243
 244         return 0;
 245 }
 246 EXPORT_SYMBOL(b53_serdes_init);
 247
 248 MODULE_AUTHOR("Florian Fainelli <f.fainelli@gmail.com>");
 249 MODULE_DESCRIPTION("B53 Switch SerDes driver");
 250 MODULE_LICENSE("Dual BSD/GPL");