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 void b53_serdes_write_blk(struct b53_device *dev, u8 offset, u16 block,
  21                                  u16 value)
  22 {
  23         b53_write16(dev, B53_SERDES_PAGE, B53_SERDES_BLKADDR, block);
  24         b53_write16(dev, B53_SERDES_PAGE, offset, value);
  25 }
  26
  27 static u16 b53_serdes_read_blk(struct b53_device *dev, u8 offset, u16 block)
  28 {
  29         u16 value;
  30
  31         b53_write16(dev, B53_SERDES_PAGE, B53_SERDES_BLKADDR, block);
  32         b53_read16(dev, B53_SERDES_PAGE, offset, &value);
  33
  34         return value;
  35 }
  36
  37 static void b53_serdes_set_lane(struct b53_device *dev, u8 lane)
  38 {
  39         if (dev->serdes_lane == lane)
  40                 return;
  41
  42         WARN_ON(lane > 1);
  43
  44         b53_serdes_write_blk(dev, B53_SERDES_LANE,
  45                              SERDES_XGXSBLK0_BLOCKADDRESS, lane);
  46         dev->serdes_lane = lane;
  47 }
  48
  49 static void b53_serdes_write(struct b53_device *dev, u8 lane,
  50                              u8 offset, u16 block, u16 value)
  51 {
  52         b53_serdes_set_lane(dev, lane);
  53         b53_serdes_write_blk(dev, offset, block, value);
  54 }
  55
  56 static u16 b53_serdes_read(struct b53_device *dev, u8 lane,
  57                            u8 offset, u16 block)
  58 {
  59         b53_serdes_set_lane(dev, lane);
  60         return b53_serdes_read_blk(dev, offset, block);
  61 }
  62
  63 void b53_serdes_config(struct b53_device *dev, int port, unsigned int mode,
  64                        const struct phylink_link_state *state)
  65 {
  66         u8 lane = b53_serdes_map_lane(dev, port);
  67         u16 reg;
  68
  69         if (lane == B53_INVALID_LANE)
  70                 return;
  71
  72         reg = b53_serdes_read(dev, lane, B53_SERDES_DIGITAL_CONTROL(1),
  73                               SERDES_DIGITAL_BLK);
  74         if (state->interface == PHY_INTERFACE_MODE_1000BASEX)
  75                 reg |= FIBER_MODE_1000X;
  76         else
  77                 reg &= ~FIBER_MODE_1000X;
  78         b53_serdes_write(dev, lane, B53_SERDES_DIGITAL_CONTROL(1),
  79                          SERDES_DIGITAL_BLK, reg);
  80 }
  81 EXPORT_SYMBOL(b53_serdes_config);
  82
  83 void b53_serdes_an_restart(struct b53_device *dev, int port)
  84 {
  85         u8 lane = b53_serdes_map_lane(dev, port);
  86         u16 reg;
  87
  88         if (lane == B53_INVALID_LANE)
  89                 return;
  90
  91         reg = b53_serdes_read(dev, lane, B53_SERDES_MII_REG(MII_BMCR),
  92                               SERDES_MII_BLK);
  93         reg |= BMCR_ANRESTART;
  94         b53_serdes_write(dev, lane, B53_SERDES_MII_REG(MII_BMCR),
  95                          SERDES_MII_BLK, reg);
  96 }
  97 EXPORT_SYMBOL(b53_serdes_an_restart);
  98
  99 int b53_serdes_link_state(struct b53_device *dev, int port,
 100                           struct phylink_link_state *state)
 101 {
 102         u8 lane = b53_serdes_map_lane(dev, port);
 103         u16 dig, bmsr;
 104
 105         if (lane == B53_INVALID_LANE)
 106                 return 1;
 107
 108         dig = b53_serdes_read(dev, lane, B53_SERDES_DIGITAL_STATUS,
 109                               SERDES_DIGITAL_BLK);
 110         bmsr = b53_serdes_read(dev, lane, B53_SERDES_MII_REG(MII_BMSR),
 111                                SERDES_MII_BLK);
 112
 113         switch ((dig >> SPEED_STATUS_SHIFT) & SPEED_STATUS_MASK) {
 114         case SPEED_STATUS_10:
 115                 state->speed = SPEED_10;
 116                 break;
 117         case SPEED_STATUS_100:
 118                 state->speed = SPEED_100;
 119                 break;
 120         case SPEED_STATUS_1000:
 121                 state->speed = SPEED_1000;
 122                 break;
 123         default:
 124         case SPEED_STATUS_2500:
 125                 state->speed = SPEED_2500;
 126                 break;
 127         }
 128
 129         state->duplex = dig & DUPLEX_STATUS ? DUPLEX_FULL : DUPLEX_HALF;
 130         state->an_complete = !!(bmsr & BMSR_ANEGCOMPLETE);
 131         state->link = !!(dig & LINK_STATUS);
 132         if (dig & PAUSE_RESOLUTION_RX_SIDE)
 133                 state->pause |= MLO_PAUSE_RX;
 134         if (dig & PAUSE_RESOLUTION_TX_SIDE)
 135                 state->pause |= MLO_PAUSE_TX;
 136
 137         return 0;
 138 }
 139 EXPORT_SYMBOL(b53_serdes_link_state);
 140
 141 void b53_serdes_link_set(struct b53_device *dev, int port, unsigned int mode,
 142                          phy_interface_t interface, bool link_up)
 143 {
 144         u8 lane = b53_serdes_map_lane(dev, port);
 145         u16 reg;
 146
 147         if (lane == B53_INVALID_LANE)
 148                 return;
 149
 150         reg = b53_serdes_read(dev, lane, B53_SERDES_MII_REG(MII_BMCR),
 151                               SERDES_MII_BLK);
 152         if (link_up)
 153                 reg &= ~BMCR_PDOWN;
 154         else
 155                 reg |= BMCR_PDOWN;
 156         b53_serdes_write(dev, lane, B53_SERDES_MII_REG(MII_BMCR),
 157                          SERDES_MII_BLK, reg);
 158 }
 159 EXPORT_SYMBOL(b53_serdes_link_set);
 160
 161 void b53_serdes_phylink_validate(struct b53_device *dev, int port,
 162                                  unsigned long *supported,
 163                                  struct phylink_link_state *state)
 164 {
 165         u8 lane = b53_serdes_map_lane(dev, port);
 166
 167         if (lane == B53_INVALID_LANE)
 168                 return;
 169
 170         switch (lane) {
 171         case 0:
 172                 phylink_set(supported, 2500baseX_Full);
 173                 /* fallthrough */
 174         case 1:
 175                 phylink_set(supported, 1000baseX_Full);
 176                 break;
 177         default:
 178                 break;
 179         }
 180 }
 181 EXPORT_SYMBOL(b53_serdes_phylink_validate);
 182
 183 int b53_serdes_init(struct b53_device *dev, int port)
 184 {
 185         u8 lane = b53_serdes_map_lane(dev, port);
 186         u16 id0, msb, lsb;
 187
 188         if (lane == B53_INVALID_LANE)
 189                 return -EINVAL;
 190
 191         id0 = b53_serdes_read(dev, lane, B53_SERDES_ID0, SERDES_ID0);
 192         msb = b53_serdes_read(dev, lane, B53_SERDES_MII_REG(MII_PHYSID1),
 193                               SERDES_MII_BLK);
 194         lsb = b53_serdes_read(dev, lane, B53_SERDES_MII_REG(MII_PHYSID2),
 195                               SERDES_MII_BLK);
 196         if (id0 == 0 || id0 == 0xffff) {
 197                 dev_err(dev->dev, "SerDes not initialized, check settings\n");
 198                 return -ENODEV;
 199         }
 200
 201         dev_info(dev->dev,
 202                  "SerDes lane %d, model: %d, rev %c%d (OUI: 0x%08x)\n",
 203                  lane, id0 & SERDES_ID0_MODEL_MASK,
 204                  (id0 >> SERDES_ID0_REV_LETTER_SHIFT) + 0x41,
 205                  (id0 >> SERDES_ID0_REV_NUM_SHIFT) & SERDES_ID0_REV_NUM_MASK,
 206                  (u32)msb << 16 | lsb);
 207
 208         return 0;
 209 }
 210 EXPORT_SYMBOL(b53_serdes_init);
 211
 212 MODULE_AUTHOR("Florian Fainelli <f.fainelli@gmail.com>");
 213 MODULE_DESCRIPTION("B53 Switch SerDes driver");
 214 MODULE_LICENSE("Dual BSD/GPL");