target/linux/generic/backport-5.15/703-08-v5.17-net-phylink-add-mac_select_pcs-method-to-phylink_mac.patch

   1 From d1e86325af377129adb7fc6f34eb044ca6068b47 Mon Sep 17 00:00:00 2001
   2 From: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk>
   3 Date: Wed, 15 Dec 2021 15:34:15 +0000
   4 Subject: [PATCH] net: phylink: add mac_select_pcs() method to phylink_mac_ops
   5
   6 mac_select_pcs() allows us to have an explicit point to query which
   7 PCS the MAC wishes to use for a particular PHY interface mode, thereby
   8 allowing us to add support to validate the link settings with the PCS.
   9
  10 Phylink will also use this to select the PCS to be used during a major
  11 configuration event without the MAC driver needing to call
  12 phylink_set_pcs().
  13
  14 Note that if mac_select_pcs() is present, the supported_interfaces
  15 bitmap must be filled in; this avoids mac_select_pcs() being called
  16 with PHY_INTERFACE_MODE_NA when we want to get support for all
  17 interface types. Phylink will return an error in phylink_create()
  18 unless this condition is satisfied.
  19
  20 Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
  21 Signed-off-by: David S. Miller <davem@davemloft.net>
  22 ---
  23  drivers/net/phy/phylink.c | 68 +++++++++++++++++++++++++++++++++------
  24  include/linux/phylink.h   | 18 +++++++++++
  25  2 files changed, 77 insertions(+), 9 deletions(-)
  26
  27 --- a/drivers/net/phy/phylink.c
  28 +++ b/drivers/net/phy/phylink.c
  29 @@ -155,6 +155,23 @@ static const char *phylink_an_mode_str(u
  30         return mode < ARRAY_SIZE(modestr) ? modestr[mode] : "unknown";
  31  }
  32
  33 +static int phylink_validate_mac_and_pcs(struct phylink *pl,
  34 +                                       unsigned long *supported,
  35 +                                       struct phylink_link_state *state)
  36 +{
  37 +       struct phylink_pcs *pcs;
  38 +
  39 +       if (pl->mac_ops->mac_select_pcs) {
  40 +               pcs = pl->mac_ops->mac_select_pcs(pl->config, state->interface);
  41 +               if (IS_ERR(pcs))
  42 +                       return PTR_ERR(pcs);
  43 +       }
  44 +
  45 +       pl->mac_ops->validate(pl->config, supported, state);
  46 +
  47 +       return phylink_is_empty_linkmode(supported) ? -EINVAL : 0;
  48 +}
  49 +
  50  static int phylink_validate_any(struct phylink *pl, unsigned long *supported,
  51                                 struct phylink_link_state *state)
  52  {
  53 @@ -170,9 +187,10 @@ static int phylink_validate_any(struct p
  54
  55                         t = *state;
  56                         t.interface = intf;
  57 -                       pl->mac_ops->validate(pl->config, s, &t);
  58 -                       linkmode_or(all_s, all_s, s);
  59 -                       linkmode_or(all_adv, all_adv, t.advertising);
  60 +                       if (!phylink_validate_mac_and_pcs(pl, s, &t)) {
  61 +                               linkmode_or(all_s, all_s, s);
  62 +                               linkmode_or(all_adv, all_adv, t.advertising);
  63 +                       }
  64                 }
  65         }
  66
  67 @@ -194,9 +212,7 @@ static int phylink_validate(struct phyli
  68                         return -EINVAL;
  69         }
  70
  71 -       pl->mac_ops->validate(pl->config, supported, state);
  72 -
  73 -       return phylink_is_empty_linkmode(supported) ? -EINVAL : 0;
  74 +       return phylink_validate_mac_and_pcs(pl, supported, state);
  75  }
  76
  77  static int phylink_parse_fixedlink(struct phylink *pl,
  78 @@ -486,10 +502,21 @@ static void phylink_mac_pcs_an_restart(s
  79  static void phylink_major_config(struct phylink *pl, bool restart,
  80                                   const struct phylink_link_state *state)
  81  {
  82 +       struct phylink_pcs *pcs = NULL;
  83         int err;
  84
  85         phylink_dbg(pl, "major config %s\n", phy_modes(state->interface));
  86
  87 +       if (pl->mac_ops->mac_select_pcs) {
  88 +               pcs = pl->mac_ops->mac_select_pcs(pl->config, state->interface);
  89 +               if (IS_ERR(pcs)) {
  90 +                       phylink_err(pl,
  91 +                                   "mac_select_pcs unexpectedly failed: %pe\n",
  92 +                                   pcs);
  93 +                       return;
  94 +               }
  95 +       }
  96 +
  97         if (pl->mac_ops->mac_prepare) {
  98                 err = pl->mac_ops->mac_prepare(pl->config, pl->cur_link_an_mode,
  99                                                state->interface);
 100 @@ -500,6 +527,12 @@ static void phylink_major_config(struct
 101                 }
 102         }
 103
 104 +       /* If we have a new PCS, switch to the new PCS after preparing the MAC
 105 +        * for the change.
 106 +        */
 107 +       if (pcs)
 108 +               phylink_set_pcs(pl, pcs);
 109 +
 110         phylink_mac_config(pl, state);
 111
 112         if (pl->pcs_ops) {
 113 @@ -879,6 +912,14 @@ struct phylink *phylink_create(struct ph
 114         struct phylink *pl;
 115         int ret;
 116
 117 +       /* Validate the supplied configuration */
 118 +       if (mac_ops->mac_select_pcs &&
 119 +           phy_interface_empty(config->supported_interfaces)) {
 120 +               dev_err(config->dev,
 121 +                       "phylink: error: empty supported_interfaces but mac_select_pcs() method present\n");
 122 +               return ERR_PTR(-EINVAL);
 123 +       }
 124 +
 125         pl = kzalloc(sizeof(*pl), GFP_KERNEL);
 126         if (!pl)
 127                 return ERR_PTR(-ENOMEM);
 128 @@ -947,9 +988,10 @@ EXPORT_SYMBOL_GPL(phylink_create);
 129   * @pl: a pointer to a &struct phylink returned from phylink_create()
 130   * @pcs: a pointer to the &struct phylink_pcs
 131   *
 132 - * Bind the MAC PCS to phylink.  This may be called after phylink_create(),
 133 - * in mac_prepare() or mac_config() methods if it is desired to dynamically
 134 - * change the PCS.
 135 + * Bind the MAC PCS to phylink.  This may be called after phylink_create().
 136 + * If it is desired to dynamically change the PCS, then the preferred method
 137 + * is to use mac_select_pcs(), but it may also be called in mac_prepare()
 138 + * or mac_config().
 139   *
 140   * Please note that there are behavioural changes with the mac_config()
 141   * callback if a PCS is present (denoting a newer setup) so removing a PCS
 142 @@ -960,6 +1002,14 @@ void phylink_set_pcs(struct phylink *pl,
 143  {
 144         pl->pcs = pcs;
 145         pl->pcs_ops = pcs->ops;
 146 +
 147 +       if (!pl->phylink_disable_state &&
 148 +           pl->cfg_link_an_mode == MLO_AN_INBAND) {
 149 +               if (pl->config->pcs_poll || pcs->poll)
 150 +                       mod_timer(&pl->link_poll, jiffies + HZ);
 151 +               else
 152 +                       del_timer(&pl->link_poll);
 153 +       }
 154  }
 155  EXPORT_SYMBOL_GPL(phylink_set_pcs);
 156
 157 --- a/include/linux/phylink.h
 158 +++ b/include/linux/phylink.h
 159 @@ -86,6 +86,7 @@ struct phylink_config {
 160  /**
 161   * struct phylink_mac_ops - MAC operations structure.
 162   * @validate: Validate and update the link configuration.
 163 + * @mac_select_pcs: Select a PCS for the interface mode.
 164   * @mac_pcs_get_state: Read the current link state from the hardware.
 165   * @mac_prepare: prepare for a major reconfiguration of the interface.
 166   * @mac_config: configure the MAC for the selected mode and state.
 167 @@ -100,6 +101,8 @@ struct phylink_mac_ops {
 168         void (*validate)(struct phylink_config *config,
 169                          unsigned long *supported,
 170                          struct phylink_link_state *state);
 171 +       struct phylink_pcs *(*mac_select_pcs)(struct phylink_config *config,
 172 +                                             phy_interface_t interface);
 173         void (*mac_pcs_get_state)(struct phylink_config *config,
 174                                   struct phylink_link_state *state);
 175         int (*mac_prepare)(struct phylink_config *config, unsigned int mode,
 176 @@ -152,6 +155,21 @@ struct phylink_mac_ops {
 177   */
 178  void validate(struct phylink_config *config, unsigned long *supported,
 179               struct phylink_link_state *state);
 180 +/**
 181 + * mac_select_pcs: Select a PCS for the interface mode.
 182 + * @config: a pointer to a &struct phylink_config.
 183 + * @interface: PHY interface mode for PCS
 184 + *
 185 + * Return the &struct phylink_pcs for the specified interface mode, or
 186 + * NULL if none is required, or an error pointer on error.
 187 + *
 188 + * This must not modify any state. It is used to query which PCS should
 189 + * be used. Phylink will use this during validation to ensure that the
 190 + * configuration is valid, and when setting a configuration to internally
 191 + * set the PCS that will be used.
 192 + */
 193 +struct phylink_pcs *mac_select_pcs(struct phylink_config *config,
 194 +                                  phy_interface_t interface);
 195
 196  /**
 197   * mac_pcs_get_state() - Read the current inband link state from the hardware