[PATCH v2 2/3] netlink: add master/slave configuration support

From: Oleksij Rempel
Date: Thu May 28 2020 - 07:54:45 EST


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@xxxxxxxxxxxxxx>
---
ethtool.8.in | 19 ++++++++++++++++
ethtool.c | 1 +
netlink/desc-ethtool.c | 2 ++
netlink/settings.c | 50 ++++++++++++++++++++++++++++++++++++++++++
4 files changed, 72 insertions(+)

diff --git a/ethtool.8.in b/ethtool.8.in
index f8b09e0..dac42f7 100644
--- a/ethtool.8.in
+++ b/ethtool.8.in
@@ -52,6 +52,10 @@
.\"
.ds MA \fIxx\fP\fB:\fP\fIyy\fP\fB:\fP\fIzz\fP\fB:\fP\fIaa\fP\fB:\fP\fIbb\fP\fB:\fP\fIcc\fP
.\"
+.\" \(*MS - master-slave property
+.\"
+.ds MS \fBmaster-preferred\fP|\fBslave-preferred\fP|\fBmaster-force\fP|\fBslave-force\fP
+.\"
.\" \(*PA - IP address
.\"
.ds PA \fIip-address\fP
@@ -255,6 +259,7 @@ ethtool \- query or control network driver and hardware settings
.RB [ wol \ \fIN\fP[\fB/\fP\fIM\fP]
.RB | \ wol \ \*(WO]
.RB [ sopass \ \*(MA]
+.RB [ master-slave \ \*(MS]
.RB [ msglvl
.IR N\fP[/\fIM\fP] \ |
.BI msglvl \ type
@@ -646,6 +651,20 @@ Sets full or half duplex mode.
.A4 port tp aui bnc mii fibre da
Selects device port.
.TP
+.BR master-slave \ \*(MS
+Configure MASTER/SLAVE role of the PHY. 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. Not all devices support this.
+.TS
+nokeep;
+lB l.
+master-preferred Prefer MASTER role on autonegotiation
+slave-preferred Prefer SLAVE role on autonegotiation
+master-force Force the PHY in MASTER role. Can be used without autonegotiation
+slave-force Force the PHY in SLAVE role. Can be used without autonegotiation
+.TE
+.TP
.A3 mdix auto on off
Selects MDI-X mode for port. May be used to override the automatic
detection feature of most adapters. An argument of \fBauto\fR means
diff --git a/ethtool.c b/ethtool.c
index 900880a..a6e9bfc 100644
--- a/ethtool.c
+++ b/ethtool.c
@@ -5196,6 +5196,7 @@ static const struct option args[] = {
" [ wol %d[/%d] | p|u|m|b|a|g|s|f|d... ]\n"
" [ sopass %x:%x:%x:%x:%x:%x ]\n"
" [ msglvl %d[/%d] | type on|off ... [--] ]\n"
+ " [ master-slave master-preferred|slave-preferred|master-force|slave-force ]\n"
},
{
.opts = "-a|--show-pause",
diff --git a/netlink/desc-ethtool.c b/netlink/desc-ethtool.c
index 76c6f13..b0a793c 100644
--- a/netlink/desc-ethtool.c
+++ b/netlink/desc-ethtool.c
@@ -85,6 +85,8 @@ static const struct pretty_nla_desc __linkmodes_desc[] = {
NLATTR_DESC_NESTED(ETHTOOL_A_LINKMODES_PEER, bitset),
NLATTR_DESC_U32(ETHTOOL_A_LINKMODES_SPEED),
NLATTR_DESC_U8(ETHTOOL_A_LINKMODES_DUPLEX),
+ NLATTR_DESC_U8(ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG),
+ NLATTR_DESC_U8(ETHTOOL_A_LINKMODES_MASTER_SLAVE_STATE),
};

static const struct pretty_nla_desc __linkstate_desc[] = {
diff --git a/netlink/settings.c b/netlink/settings.c
index 8be5a22..851de15 100644
--- a/netlink/settings.c
+++ b/netlink/settings.c
@@ -37,6 +37,21 @@ static const char *const names_duplex[] = {
[DUPLEX_FULL] = "Full",
};

+static const char *const names_master_slave_state[] = {
+ [MASTER_SLAVE_STATE_UNKNOWN] = "Unknown",
+ [MASTER_SLAVE_STATE_MASTER] = "Master",
+ [MASTER_SLAVE_STATE_SLAVE] = "Slave",
+ [MASTER_SLAVE_STATE_ERR] = "Resolution error",
+};
+
+static const char *const names_master_slave_cfg[] = {
+ [MASTER_SLAVE_CFG_UNKNOWN] = "Unknown",
+ [MASTER_SLAVE_CFG_MASTER_PREFERRED] = "preferred Master",
+ [MASTER_SLAVE_CFG_SLAVE_PREFERRED] = "preferred Slave",
+ [MASTER_SLAVE_CFG_MASTER_FORCE] = "forced Master",
+ [MASTER_SLAVE_CFG_SLAVE_FORCE] = "forced Slave",
+};
+
static const char *const names_port[] = {
[PORT_TP] = "Twisted Pair",
[PORT_AUI] = "AUI",
@@ -520,6 +535,25 @@ int linkmodes_reply_cb(const struct nlmsghdr *nlhdr, void *data)
printf("\tAuto-negotiation: %s\n",
(autoneg == AUTONEG_DISABLE) ? "off" : "on");
}
+ if (tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG]) {
+ uint8_t val;
+
+ val = mnl_attr_get_u8(tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG]);
+
+ print_banner(nlctx);
+ print_enum(names_master_slave_cfg,
+ ARRAY_SIZE(names_master_slave_cfg), val,
+ "Port mode cfg");
+ }
+ if (tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_STATE]) {
+ uint8_t val;
+
+ val = mnl_attr_get_u8(tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_STATE]);
+ print_banner(nlctx);
+ print_enum(names_master_slave_state,
+ ARRAY_SIZE(names_master_slave_state), val,
+ "Port mode status");
+ }

return MNL_CB_OK;
err:
@@ -827,6 +861,14 @@ static const struct lookup_entry_u32 duplex_values[] = {
{}
};

+static const struct lookup_entry_u8 master_slave_values[] = {
+ { .arg = "master-preferred", .val = MASTER_SLAVE_CFG_MASTER_PREFERRED },
+ { .arg = "slave-preferred", .val = MASTER_SLAVE_CFG_SLAVE_PREFERRED },
+ { .arg = "master-force", .val = MASTER_SLAVE_CFG_MASTER_FORCE },
+ { .arg = "slave-force", .val = MASTER_SLAVE_CFG_SLAVE_FORCE },
+ {}
+};
+
char wol_bit_chars[WOL_MODE_COUNT] = {
[WAKE_PHY_BIT] = 'p',
[WAKE_UCAST_BIT] = 'u',
@@ -917,6 +959,14 @@ static const struct param_parser sset_params[] = {
.handler_data = duplex_values,
.min_argc = 1,
},
+ {
+ .arg = "master-slave",
+ .group = ETHTOOL_MSG_LINKMODES_SET,
+ .type = ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG,
+ .handler = nl_parse_lookup_u8,
+ .handler_data = master_slave_values,
+ .min_argc = 1,
+ },
{
.arg = "wol",
.group = ETHTOOL_MSG_WOL_SET,
--
2.26.2