target/linux/generic/pending-5.4/751-net-phylink-make-Broadcom-BCM84881-based-SFPs-work.patch

   1 From 3d8592a23dd67fb78ad85ddf711a059d3880fcb4 Mon Sep 17 00:00:00 2001
   2 From: Russell King <rmk+kernel@armlinux.org.uk>
   3 Date: Fri, 8 Nov 2019 17:19:16 +0000
   4 Subject: [PATCH 654/660] net: phylink: make Broadcom BCM84881 based SFPs work
   5
   6 The Broadcom BCM84881 does not appear to send the SGMII control word
   7 when operating in SGMII mode, which causes network adapters to fail
   8 to link with the PHY, or decide to operate at fixed 1G speed, even if
   9 the PHY negotiated 100M.
  10
  11 Work around this by detecting the Broadcom BCM84881 and switch to phy
  12 mode rather than inband mode.
  13
  14 Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
  15 ---
  16  drivers/net/phy/phylink.c | 17 ++++++++++++++++-
  17  1 file changed, 16 insertions(+), 1 deletion(-)
  18
  19 --- a/drivers/net/phy/phylink.c
  20 +++ b/drivers/net/phy/phylink.c
  21 @@ -1787,12 +1787,22 @@ static void phylink_sfp_link_up(void *up
  22         phylink_run_resolve(pl);
  23  }
  24
  25 +/* The Broadcom BCM84881 in the Methode DM7052 is unable to provide a SGMII
  26 + * or 802.3z control word, so inband will not work.
  27 + */
  28 +static bool phylink_phy_no_inband(struct phy_device *phy)
  29 +{
  30 +       return phy->is_c45 &&
  31 +               (phy->c45_ids.device_ids[1] & 0xfffffff0) == 0xae025150;
  32 +}
  33 +
  34  static int phylink_sfp_connect_phy(void *upstream, struct phy_device *phy)
  35  {
  36         struct phylink *pl = upstream;
  37         __ETHTOOL_DECLARE_LINK_MODE_MASK(supported);
  38         __ETHTOOL_DECLARE_LINK_MODE_MASK(advertising);
  39         phy_interface_t interface;
  40 +       u8 mode;
  41         int ret;
  42
  43         /*
  44 @@ -1807,8 +1817,13 @@ static int phylink_sfp_connect_phy(void
  45         ethtool_convert_legacy_u32_to_link_mode(supported, phy->supported);
  46         ethtool_convert_legacy_u32_to_link_mode(advertising, phy->advertising);
  47
  48 +       if (phylink_phy_no_inband(phy))
  49 +               mode = MLO_AN_PHY;
  50 +       else
  51 +               mode = MLO_AN_INBAND;
  52 +
  53         /* Do the initial configuration */
  54 -       ret = phylink_sfp_config(pl, ML_AN_INBAND, supported, advertising);
  55 +       ret = phylink_sfp_config(pl, mode, supported, advertising);
  56         if (ret < 0)
  57                 return ret;
  58