This UAPI is needed for BroadR-Reach 100BASE-T1 devices. Due to lack of
auto-negotiation support, we needed to be able to configure the
MASTER-SLAVE role of the port manually or from an application in user
space.

The same UAPI can be used for 1000BASE-T or MultiGBASE-T devices to
force MASTER or SLAVE role. See IEEE 802.3-2018:
22.2.4.3.7 MASTER-SLAVE control register (Register 9)
22.2.4.3.8 MASTER-SLAVE status register (Register 10)
40.5.2 MASTER-SLAVE configuration resolution
45.2.1.185.1 MASTER-SLAVE config value (1.2100.14)
45.2.7.10 MultiGBASE-T AN control 1 register (Register 7.32)

The MASTER-SLAVE role affects the clock configuration:

-------------------------------------------------------------------------------
When the  PHY is configured as MASTER, the PMA Transmit function shall
source TX_TCLK from a local clock source. When configured as SLAVE, the
PMA Transmit function shall source TX_TCLK from the clock recovered from
data stream provided by MASTER.

iMX6Q                     KSZ9031                XXX
------\                /-----------\        /------------\
      |                |           |        |            |
 MAC  |<----RGMII----->| PHY Slave |<------>| PHY Master |
      |<--- 125 MHz ---+-<------/  |        | \          |
------/                \-----------/        \------------/
                                               ^
                                                \-TX_TCLK

-------------------------------------------------------------------------------

Since some clock or link related issues are only reproducible in a
specific MASTER-SLAVE-role, MAC and PHY configuration, it is beneficial
to provide generic (not 100BASE-T1 specific) interface to the user space
for configuration flexibility and trouble shooting.

Signed-off-by: Oleksij Rempel <o.rem...@pengutronix.de>
---
 Documentation/networking/ethtool-netlink.rst |  3 +
 drivers/net/phy/phy.c                        |  7 +-
 drivers/net/phy/phy_device.c                 | 89 ++++++++++++++++++++
 include/linux/phy.h                          |  3 +
 include/uapi/linux/ethtool.h                 | 29 ++++++-
 include/uapi/linux/ethtool_netlink.h         |  2 +
 include/uapi/linux/mii.h                     |  2 +
 net/ethtool/linkmodes.c                      | 15 +++-
 8 files changed, 147 insertions(+), 3 deletions(-)

diff --git a/Documentation/networking/ethtool-netlink.rst 
b/Documentation/networking/ethtool-netlink.rst
index 567326491f80b..c32b109ebe1b3 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -399,6 +399,8 @@ Kernel response contents:
   ``ETHTOOL_A_LINKMODES_PEER``          bitset  partner link modes
   ``ETHTOOL_A_LINKMODES_SPEED``         u32     link speed (Mb/s)
   ``ETHTOOL_A_LINKMODES_DUPLEX``        u8      duplex mode
+  ``ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG``  u8      Master/slave port mode
+  ``ETHTOOL_A_LINKMODES_MASTER_SLAVE_STATE``  u8      Master/slave port mode
   ====================================  ======  ==========================
 
 For ``ETHTOOL_A_LINKMODES_OURS``, value represents advertised modes and mask
@@ -421,6 +423,7 @@ Request contents:
   ``ETHTOOL_A_LINKMODES_PEER``          bitset  partner link modes
   ``ETHTOOL_A_LINKMODES_SPEED``         u32     link speed (Mb/s)
   ``ETHTOOL_A_LINKMODES_DUPLEX``        u8      duplex mode
+  ``ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG``  u8      Master/slave port mode
   ====================================  ======  ==========================
 
 ``ETHTOOL_A_LINKMODES_OURS`` bit set allows setting advertised link modes. If
diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index 72c69a9c8a98a..a6a774beb2f90 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -285,6 +285,9 @@ int phy_ethtool_ksettings_set(struct phy_device *phydev,
              duplex != DUPLEX_FULL)))
                return -EINVAL;
 
+       if (!ethtool_validate_master_slave_cfg(cmd->base.master_slave_cfg))
+               return -EINVAL;
+
        phydev->autoneg = autoneg;
 
        phydev->speed = speed;
@@ -295,7 +298,7 @@ int phy_ethtool_ksettings_set(struct phy_device *phydev,
                         phydev->advertising, autoneg == AUTONEG_ENABLE);
 
        phydev->duplex = duplex;
-
+       phydev->master_slave_set = cmd->base.master_slave_cfg;
        phydev->mdix_ctrl = cmd->base.eth_tp_mdix_ctrl;
 
        /* Restart the PHY */
@@ -314,6 +317,8 @@ void phy_ethtool_ksettings_get(struct phy_device *phydev,
 
        cmd->base.speed = phydev->speed;
        cmd->base.duplex = phydev->duplex;
+       cmd->base.master_slave_cfg = phydev->master_slave_get;
+       cmd->base.master_slave_state = phydev->master_slave_state;
        if (phydev->interface == PHY_INTERFACE_MODE_MOCA)
                cmd->base.port = PORT_BNC;
        else
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index ac2784192472f..756c3642d0f8e 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -9,6 +9,7 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
+#include <linux/bitfield.h>
 #include <linux/kernel.h>
 #include <linux/string.h>
 #include <linux/errno.h>
@@ -1768,6 +1769,84 @@ int genphy_setup_forced(struct phy_device *phydev)
 }
 EXPORT_SYMBOL(genphy_setup_forced);
 
+static int genphy_setup_master_slave(struct phy_device *phydev)
+{
+       u16 ctl = 0;
+
+       if (!phydev->is_gigabit_capable)
+               return 0;
+
+       switch (phydev->master_slave_set) {
+       case PORT_MODE_CFG_MASTER_PREFERRED:
+               ctl |= CTL1000_PREFER_MASTER;
+               break;
+       case PORT_MODE_CFG_SLAVE_PREFERRED:
+               break;
+       case PORT_MODE_CFG_MASTER_FORCE:
+               ctl |= CTL1000_AS_MASTER;
+               /* fallthrough */
+       case PORT_MODE_CFG_SLAVE_FORCE:
+               ctl |= CTL1000_ENABLE_MASTER;
+               break;
+       case PORT_MODE_CFG_UNKNOWN:
+               return 0;
+       default:
+               phydev_warn(phydev, "Unsupported Master/Slave mode\n");
+               return 0;
+       }
+
+       return phy_modify_changed(phydev, MII_CTRL1000,
+                                 (CTL1000_ENABLE_MASTER | CTL1000_AS_MASTER |
+                                  CTL1000_PREFER_MASTER), ctl);
+}
+
+static int genphy_read_master_slave(struct phy_device *phydev)
+{
+       int cfg, state = 0;
+       u16 val;
+
+       phydev->master_slave_get = 0;
+       phydev->master_slave_state = 0;
+
+       if (!phydev->is_gigabit_capable)
+               return 0;
+
+       val = phy_read(phydev, MII_CTRL1000);
+       if (val < 0)
+               return val;
+
+       if (val & CTL1000_ENABLE_MASTER) {
+               if (val & CTL1000_AS_MASTER)
+                       cfg = PORT_MODE_CFG_MASTER_FORCE;
+               else
+                       cfg = PORT_MODE_CFG_SLAVE_FORCE;
+       } else {
+               if (val & CTL1000_PREFER_MASTER)
+                       cfg = PORT_MODE_CFG_MASTER_PREFERRED;
+               else
+                       cfg = PORT_MODE_CFG_SLAVE_PREFERRED;
+       }
+
+       val = phy_read(phydev, MII_STAT1000);
+       if (val < 0)
+               return val;
+
+       if (val & LPA_1000MSFAIL) {
+               state = PORT_MODE_STATE_ERR;
+       } else if (phydev->link) {
+               /* this bits are valid only for active link */
+               if (val & LPA_1000MSRES)
+                       state = PORT_MODE_STATE_MASTER;
+               else
+                       state = PORT_MODE_STATE_SLAVE;
+       }
+
+       phydev->master_slave_get = cfg;
+       phydev->master_slave_state = state;
+
+       return 0;
+}
+
 /**
  * genphy_restart_aneg - Enable and Restart Autonegotiation
  * @phydev: target phy_device struct
@@ -1826,6 +1905,12 @@ int __genphy_config_aneg(struct phy_device *phydev, bool 
changed)
        if (genphy_config_eee_advert(phydev))
                changed = true;
 
+       err = genphy_setup_master_slave(phydev);
+       if (err < 0)
+               return err;
+       else if (err)
+               changed = true;
+
        if (AUTONEG_ENABLE != phydev->autoneg)
                return genphy_setup_forced(phydev);
 
@@ -2060,6 +2145,10 @@ int genphy_read_status(struct phy_device *phydev)
        phydev->pause = 0;
        phydev->asym_pause = 0;
 
+       err = genphy_read_master_slave(phydev);
+       if (err < 0)
+               return err;
+
        err = genphy_read_lpa(phydev);
        if (err < 0)
                return err;
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 2432ca463ddc0..19cd4fe6efbf1 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -431,6 +431,9 @@ struct phy_device {
        int duplex;
        int pause;
        int asym_pause;
+       u8 master_slave_get;
+       u8 master_slave_set;
+       u8 master_slave_state;
 
        /* Union of PHY and Attached devices' supported link modes */
        /* See ethtool.h for more info */
diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index 92f737f101178..eb680e3d6bda5 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -1666,6 +1666,31 @@ static inline int ethtool_validate_duplex(__u8 duplex)
        return 0;
 }
 
+/* Port mode */
+#define PORT_MODE_CFG_UNKNOWN          0
+#define PORT_MODE_CFG_MASTER_PREFERRED 1
+#define PORT_MODE_CFG_SLAVE_PREFERRED  2
+#define PORT_MODE_CFG_MASTER_FORCE     3
+#define PORT_MODE_CFG_SLAVE_FORCE      4
+#define PORT_MODE_STATE_UNKNOWN                0
+#define PORT_MODE_STATE_MASTER         1
+#define PORT_MODE_STATE_SLAVE          2
+#define PORT_MODE_STATE_ERR            3
+
+static inline int ethtool_validate_master_slave_cfg(__u8 cfg)
+{
+       switch (cfg) {
+       case PORT_MODE_CFG_MASTER_PREFERRED:
+       case PORT_MODE_CFG_SLAVE_PREFERRED:
+       case PORT_MODE_CFG_MASTER_FORCE:
+       case PORT_MODE_CFG_SLAVE_FORCE:
+       case PORT_MODE_CFG_UNKNOWN:
+               return 1;
+       }
+
+       return 0;
+}
+
 /* Which connector port. */
 #define PORT_TP                        0x00
 #define PORT_AUI               0x01
@@ -1904,7 +1929,9 @@ struct ethtool_link_settings {
        __u8    eth_tp_mdix_ctrl;
        __s8    link_mode_masks_nwords;
        __u8    transceiver;
-       __u8    reserved1[3];
+       __u8    master_slave_cfg;
+       __u8    master_slave_state;
+       __u8    reserved1[1];
        __u32   reserved[7];
        __u32   link_mode_masks[0];
        /* layout of link_mode_masks fields:
diff --git a/include/uapi/linux/ethtool_netlink.h 
b/include/uapi/linux/ethtool_netlink.h
index 7fde76366ba46..bf1d310e20bc6 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -216,6 +216,8 @@ enum {
        ETHTOOL_A_LINKMODES_PEER,               /* bitset */
        ETHTOOL_A_LINKMODES_SPEED,              /* u32 */
        ETHTOOL_A_LINKMODES_DUPLEX,             /* u8 */
+       ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG,   /* u8 */
+       ETHTOOL_A_LINKMODES_MASTER_SLAVE_STATE, /* u8 */
 
        /* add new constants above here */
        __ETHTOOL_A_LINKMODES_CNT,
diff --git a/include/uapi/linux/mii.h b/include/uapi/linux/mii.h
index 90f9b4e1ba277..39f7c44baf535 100644
--- a/include/uapi/linux/mii.h
+++ b/include/uapi/linux/mii.h
@@ -151,11 +151,13 @@
 /* 1000BASE-T Control register */
 #define ADVERTISE_1000FULL     0x0200  /* Advertise 1000BASE-T full duplex */
 #define ADVERTISE_1000HALF     0x0100  /* Advertise 1000BASE-T half duplex */
+#define CTL1000_PREFER_MASTER  0x0400  /* prefer to operate as master */
 #define CTL1000_AS_MASTER      0x0800
 #define CTL1000_ENABLE_MASTER  0x1000
 
 /* 1000BASE-T Status register */
 #define LPA_1000MSFAIL         0x8000  /* Master/Slave resolution failure */
+#define LPA_1000MSRES          0x4000  /* Master/Slave resolution status */
 #define LPA_1000LOCALRXOK      0x2000  /* Link partner local receiver status */
 #define LPA_1000REMRXOK                0x1000  /* Link partner remote receiver 
status */
 #define LPA_1000FULL           0x0800  /* Link partner 1000BASE-T full duplex 
*/
diff --git a/net/ethtool/linkmodes.c b/net/ethtool/linkmodes.c
index 452608c6d8562..f67da2f1ba8a1 100644
--- a/net/ethtool/linkmodes.c
+++ b/net/ethtool/linkmodes.c
@@ -27,6 +27,8 @@ linkmodes_get_policy[ETHTOOL_A_LINKMODES_MAX + 1] = {
        [ETHTOOL_A_LINKMODES_PEER]              = { .type = NLA_REJECT },
        [ETHTOOL_A_LINKMODES_SPEED]             = { .type = NLA_REJECT },
        [ETHTOOL_A_LINKMODES_DUPLEX]            = { .type = NLA_REJECT },
+       [ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG]  = { .type = NLA_REJECT },
+       [ETHTOOL_A_LINKMODES_MASTER_SLAVE_STATE]        = { .type = NLA_REJECT 
},
 };
 
 static int linkmodes_prepare_data(const struct ethnl_req_info *req_base,
@@ -69,6 +71,8 @@ static int linkmodes_reply_size(const struct ethnl_req_info 
*req_base,
        len = nla_total_size(sizeof(u8)) /* LINKMODES_AUTONEG */
                + nla_total_size(sizeof(u32)) /* LINKMODES_SPEED */
                + nla_total_size(sizeof(u8)) /* LINKMODES_DUPLEX */
+               + nla_total_size(sizeof(u8)) /* LINKMODES_MASTER_SLAVE_CFG */
+               + nla_total_size(sizeof(u8)) /* LINKMODES_MASTER_SLAVE_STATE */
                + 0;
        ret = ethnl_bitset_size(ksettings->link_modes.advertising,
                                ksettings->link_modes.supported,
@@ -119,7 +123,12 @@ static int linkmodes_fill_reply(struct sk_buff *skb,
        }
 
        if (nla_put_u32(skb, ETHTOOL_A_LINKMODES_SPEED, lsettings->speed) ||
-           nla_put_u8(skb, ETHTOOL_A_LINKMODES_DUPLEX, lsettings->duplex))
+           nla_put_u8(skb, ETHTOOL_A_LINKMODES_DUPLEX, lsettings->duplex) ||
+           nla_put_u8(skb, ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG,
+                      lsettings->master_slave_cfg) ||
+           nla_put_u8(skb, ETHTOOL_A_LINKMODES_MASTER_SLAVE_STATE,
+                      lsettings->master_slave_state))
+
                return -EMSGSIZE;
 
        return 0;
@@ -249,6 +258,8 @@ linkmodes_set_policy[ETHTOOL_A_LINKMODES_MAX + 1] = {
        [ETHTOOL_A_LINKMODES_PEER]              = { .type = NLA_REJECT },
        [ETHTOOL_A_LINKMODES_SPEED]             = { .type = NLA_U32 },
        [ETHTOOL_A_LINKMODES_DUPLEX]            = { .type = NLA_U8 },
+       [ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG]  = { .type = NLA_U8 },
+       [ETHTOOL_A_LINKMODES_MASTER_SLAVE_STATE]        = { .type = NLA_REJECT 
},
 };
 
 /* Set advertised link modes to all supported modes matching requested speed
@@ -311,6 +322,8 @@ static int ethnl_update_linkmodes(struct genl_info *info, 
struct nlattr **tb,
                         mod);
        ethnl_update_u8(&lsettings->duplex, tb[ETHTOOL_A_LINKMODES_DUPLEX],
                        mod);
+       ethnl_update_u8(&lsettings->master_slave_cfg,
+                       tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG], mod);
 
        if (!tb[ETHTOOL_A_LINKMODES_OURS] && lsettings->autoneg &&
            (req_speed || req_duplex) &&
-- 
2.26.2

Reply via email to