[PATCH net-next v4 1/2] ethtool: provide UAPI for PHY master/slave configuration.

Oleksij Rempel
2020-05-01T07:46:50Z

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.rempel@pengutronix.de>
---
Documentation/networking/ethtool-netlink.rst | 35 ++++----
drivers/net/phy/phy.c | 4 +-
drivers/net/phy/phy_device.c | 95 ++++++++++++++++++++
include/linux/phy.h | 3 +
include/uapi/linux/ethtool.h | 16 +++-
include/uapi/linux/ethtool_netlink.h | 2 +
include/uapi/linux/mii.h | 2 +
net/ethtool/linkmodes.c | 48 ++++++++++
8 files changed, 187 insertions(+), 18 deletions(-)

diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index 567326491f80b..8f5cefc539cf1 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -392,14 +392,16 @@ Request contents:

Kernel response contents:

- ==================================== ====== ==========================
- ``ETHTOOL_A_LINKMODES_HEADER`` nested reply header
- ``ETHTOOL_A_LINKMODES_AUTONEG`` u8 autonegotiation status
- ``ETHTOOL_A_LINKMODES_OURS`` bitset advertised link modes
- ``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_HEADER`` nested reply header
+ ``ETHTOOL_A_LINKMODES_AUTONEG`` u8 autonegotiation status
+ ``ETHTOOL_A_LINKMODES_OURS`` bitset advertised link modes
+ ``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 state
+ ========================================== ====== ==========================

For ``ETHTOOL_A_LINKMODES_OURS``, value represents advertised modes and mask
represents supported modes. ``ETHTOOL_A_LINKMODES_PEER`` in the reply is a bit
@@ -414,14 +416,15 @@ LINKMODES_SET

Request contents:

- ==================================== ====== ==========================
- ``ETHTOOL_A_LINKMODES_HEADER`` nested request header
- ``ETHTOOL_A_LINKMODES_AUTONEG`` u8 autonegotiation status
- ``ETHTOOL_A_LINKMODES_OURS`` bitset advertised link modes
- ``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_HEADER`` nested request header
+ ``ETHTOOL_A_LINKMODES_AUTONEG`` u8 autonegotiation status
+ ``ETHTOOL_A_LINKMODES_OURS`` bitset advertised link modes
+ ``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
autonegotiation is on (either set now or kept from before), advertised modes
diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index 72c69a9c8a98a..8c22d02b4218e 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -295,7 +295,7 @@ 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 +314,8 @@ 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..89a28345e04dd 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -1768,6 +1768,91 @@ 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) {
+ if (phydev->master_slave_set != MASTER_SLAVE_CFG_UNKNOWN)
+ return -EOPNOTSUPP;
+ else
+ return 0;
+ }
+
+ switch (phydev->master_slave_set) {
+ case MASTER_SLAVE_CFG_MASTER_PREFERRED:
+ ctl |= CTL1000_PREFER_MASTER;
+ break;
+ case MASTER_SLAVE_CFG_SLAVE_PREFERRED:
+ break;
+ case MASTER_SLAVE_CFG_MASTER_FORCE:
+ ctl |= CTL1000_AS_MASTER;
+ /* fallthrough */
+ case MASTER_SLAVE_CFG_SLAVE_FORCE:
+ ctl |= CTL1000_ENABLE_MASTER;
+ break;
+ case MASTER_SLAVE_CFG_UNKNOWN:
+ return 0;
+ default:
+ phydev_warn(phydev, "Unsupported Master/Slave mode\n");
+ return -EOPNOTSUPP;
+ }
+
+ 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;
+
+ if (!phydev->is_gigabit_capable) {
+ phydev->master_slave_get = MASTER_SLAVE_CFG_UNSUPPORTED;
+ phydev->master_slave_state = MASTER_SLAVE_STATE_UNSUPPORTED;
+ return 0;
+ }
+
+ phydev->master_slave_get = MASTER_SLAVE_CFG_UNKNOWN;
+ phydev->master_slave_state = MASTER_SLAVE_STATE_UNKNOWN;
+
+ val = phy_read(phydev, MII_CTRL1000);
+ if (val < 0)
+ return val;
+
+ if (val & CTL1000_ENABLE_MASTER) {
+ if (val & CTL1000_AS_MASTER)
+ cfg = MASTER_SLAVE_CFG_MASTER_FORCE;
+ else
+ cfg = MASTER_SLAVE_CFG_SLAVE_FORCE;
+ } else {
+ if (val & CTL1000_PREFER_MASTER)
+ cfg = MASTER_SLAVE_CFG_MASTER_PREFERRED;
+ else
+ cfg = MASTER_SLAVE_CFG_SLAVE_PREFERRED;
+ }
+
+ val = phy_read(phydev, MII_STAT1000);
+ if (val < 0)
+ return val;
+
+ if (val & LPA_1000MSFAIL) {
+ state = MASTER_SLAVE_STATE_ERR;
+ } else if (phydev->link) {
+ /* this bits are valid only for active link */
+ if (val & LPA_1000MSRES)
+ state = MASTER_SLAVE_STATE_MASTER;
+ else
+ state = MASTER_SLAVE_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 +1911,12 @@ 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 +2151,10 @@ 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..8c36c3b45c1aa 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -1666,6 +1666,18 @@ static inline int ethtool_validate_duplex(__u8 duplex)
return 0;
}

+#define MASTER_SLAVE_CFG_UNKNOWN 0
+#define MASTER_SLAVE_CFG_MASTER_PREFERRED 1
+#define MASTER_SLAVE_CFG_SLAVE_PREFERRED 2
+#define MASTER_SLAVE_CFG_MASTER_FORCE 3
+#define MASTER_SLAVE_CFG_SLAVE_FORCE 4
+#define MASTER_SLAVE_CFG_UNSUPPORTED 5
+#define MASTER_SLAVE_STATE_UNKNOWN 0
+#define MASTER_SLAVE_STATE_MASTER 1
+#define MASTER_SLAVE_STATE_SLAVE 2
+#define MASTER_SLAVE_STATE_ERR 3
+#define MASTER_SLAVE_STATE_UNSUPPORTED 4
+
/* Which connector port. */
#define PORT_TP 0x00
#define PORT_AUI 0x01
@@ -1904,7 +1916,9 @@ 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..8268b9b86ebc7 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,
@@ -63,6 +65,7 @@ static int linkmodes_reply_size(const struct ethnl_req_info *req_base,
{
const struct linkmodes_reply_data *data = LINKMODES_REPDATA(reply_base);
const struct ethtool_link_ksettings *ksettings = &data->ksettings;
+ const struct ethtool_link_settings *lsettings = &ksettings->base;
bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
int len, ret;

@@ -86,6 +89,12 @@ static int linkmodes_reply_size(const struct ethnl_req_info *req_base,
len += ret;
}

+ if (lsettings->master_slave_cfg != MASTER_SLAVE_CFG_UNSUPPORTED)
+ len += nla_total_size(sizeof(u8));
+
+ if (lsettings->master_slave_state != MASTER_SLAVE_STATE_UNSUPPORTED)
+ len += nla_total_size(sizeof(u8));
+
return len;
}

@@ -122,6 +131,20 @@ static int linkmodes_fill_reply(struct sk_buff *skb,
nla_put_u8(skb, ETHTOOL_A_LINKMODES_DUPLEX, lsettings->duplex))
return -EMSGSIZE;

+ if (lsettings->master_slave_cfg != MASTER_SLAVE_CFG_UNSUPPORTED) {
+ ret = nla_put_u8(skb, ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG,
+ lsettings->master_slave_cfg);
+ if (ret < 0)
+ return -EMSGSIZE;
+ }
+
+ if (lsettings->master_slave_state != MASTER_SLAVE_STATE_UNSUPPORTED) {
+ ret = nla_put_u8(skb, ETHTOOL_A_LINKMODES_MASTER_SLAVE_STATE,
+ lsettings->master_slave_state);
+ if (ret < 0)
+ return -EMSGSIZE;
+ }
+
return 0;
}

@@ -249,6 +272,8 @@ 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
@@ -287,14 +312,35 @@ static bool ethnl_auto_linkmodes(struct ethtool_link_ksettings *ksettings,
__ETHTOOL_LINK_MODE_MASK_NBITS);
}

+static int ethnl_validate_master_slave_cfg(u8 cfg)
+{
+ switch (cfg) {
+ case MASTER_SLAVE_CFG_MASTER_PREFERRED:
+ case MASTER_SLAVE_CFG_SLAVE_PREFERRED:
+ case MASTER_SLAVE_CFG_MASTER_FORCE:
+ case MASTER_SLAVE_CFG_SLAVE_FORCE:
+ return 1;
+ }
+
+ return 0;
+}
+
static int ethnl_update_linkmodes(struct genl_info *info, struct nlattr **tb,
struct ethtool_link_ksettings *ksettings,
bool *mod)
{
struct ethtool_link_settings *lsettings = &ksettings->base;
bool req_speed, req_duplex;
+ const struct nlattr *attr;
int ret;

+ attr = tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG];
+ if (attr) {
+ u8 cfg = nla_get_u8(tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG]);
+ if (!ethnl_validate_master_slave_cfg(cfg))
+ return -EOPNOTSUPP;
+ }
+
*mod = false;
req_speed = tb[ETHTOOL_A_LINKMODES_SPEED];
req_duplex = tb[ETHTOOL_A_LINKMODES_DUPLEX];
@@ -311,6 +357,8 @@ 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