[PATCH v3 2/6] net: phy: introduce core support for phy-mode = "10g-qxgmii"

From: Luo Jie
Date: Wed Nov 15 2023 - 09:09:06 EST


From: Vladimir Oltean <vladimir.oltean@xxxxxxx>

10G-QXGMII is a MAC-to-PHY interface defined by the USXGMII multiport
specification. It uses the same signaling as USXGMII, but it multiplexes
4 ports over the link, resulting in a maximum speed of 2.5G per port.

Some in-tree SoCs like the NXP LS1028A use "usxgmii" when they mean
either the single-port USXGMII or the quad-port 10G-QXGMII variant, and
they could get away just fine with that thus far. But there is a need to
distinguish between the 2 as far as SerDes drivers are concerned.

Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
Signed-off-by: Luo Jie <quic_luoj@xxxxxxxxxxx>
---
.../devicetree/bindings/net/ethernet-controller.yaml | 1 +
Documentation/networking/phy.rst | 6 ++++++
drivers/net/phy/phy-core.c | 1 +
drivers/net/phy/phylink.c | 12 ++++++++++--
include/linux/phy.h | 4 ++++
include/linux/phylink.h | 1 +
6 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/ethernet-controller.yaml b/Documentation/devicetree/bindings/net/ethernet-controller.yaml
index 9f6a5ccbcefe..044880d804db 100644
--- a/Documentation/devicetree/bindings/net/ethernet-controller.yaml
+++ b/Documentation/devicetree/bindings/net/ethernet-controller.yaml
@@ -104,6 +104,7 @@ properties:
- usxgmii
- 10gbase-r
- 25gbase-r
+ - 10g-qxgmii

phy-mode:
$ref: "#/properties/phy-connection-type"
diff --git a/Documentation/networking/phy.rst b/Documentation/networking/phy.rst
index 1283240d7620..f64641417c54 100644
--- a/Documentation/networking/phy.rst
+++ b/Documentation/networking/phy.rst
@@ -327,6 +327,12 @@ Some of the interface modes are described below:
This is the Penta SGMII mode, it is similar to QSGMII but it combines 5
SGMII lines into a single link compared to 4 on QSGMII.

+``PHY_INTERFACE_MODE_10G_QXGMII``
+ Represents the 10G-QXGMII PHY-MAC interface as defined by the Cisco USXGMII
+ Multiport Copper Interface document. It supports 4 ports over a 10.3125 GHz
+ SerDes lane, each port having speeds of 2.5G / 1G / 100M / 10M achieved
+ through symbol replication. The PCS expects the standard USXGMII code word.
+
Pause frames / flow control
===========================

diff --git a/drivers/net/phy/phy-core.c b/drivers/net/phy/phy-core.c
index 966c93cbe616..1cd58723d6d0 100644
--- a/drivers/net/phy/phy-core.c
+++ b/drivers/net/phy/phy-core.c
@@ -141,6 +141,7 @@ int phy_interface_num_ports(phy_interface_t interface)
return 1;
case PHY_INTERFACE_MODE_QSGMII:
case PHY_INTERFACE_MODE_QUSGMII:
+ case PHY_INTERFACE_MODE_10G_QXGMII:
return 4;
case PHY_INTERFACE_MODE_PSGMII:
return 5;
diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 162f51b0986a..e9ab20bd6984 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -191,6 +191,7 @@ static unsigned int phylink_pcs_neg_mode(unsigned int mode, phy_interface_t inte
case PHY_INTERFACE_MODE_QSGMII:
case PHY_INTERFACE_MODE_QUSGMII:
case PHY_INTERFACE_MODE_USXGMII:
+ case PHY_INTERFACE_MODE_10G_QXGMII:
/* These protocols are designed for use with a PHY which
* communicates its negotiation result back to the MAC via
* inband communication. Note: there exist PHYs that run
@@ -283,6 +284,7 @@ static int phylink_interface_max_speed(phy_interface_t interface)
return SPEED_1000;

case PHY_INTERFACE_MODE_2500BASEX:
+ case PHY_INTERFACE_MODE_10G_QXGMII:
return SPEED_2500;

case PHY_INTERFACE_MODE_5GBASER:
@@ -552,7 +554,11 @@ static unsigned long phylink_get_capabilities(phy_interface_t interface,

switch (interface) {
case PHY_INTERFACE_MODE_USXGMII:
- caps |= MAC_10000FD | MAC_5000FD | MAC_2500FD;
+ caps |= MAC_10000FD | MAC_5000FD;
+ fallthrough;
+
+ case PHY_INTERFACE_MODE_10G_QXGMII:
+ caps |= MAC_2500FD;
fallthrough;

case PHY_INTERFACE_MODE_RGMII_TXID:
@@ -972,6 +978,7 @@ static int phylink_parse_mode(struct phylink *pl,
phylink_set(pl->supported, 25000baseSR_Full);
fallthrough;
case PHY_INTERFACE_MODE_USXGMII:
+ case PHY_INTERFACE_MODE_10G_QXGMII:
case PHY_INTERFACE_MODE_10GKR:
case PHY_INTERFACE_MODE_10GBASER:
phylink_set(pl->supported, 10baseT_Half);
@@ -1844,7 +1851,8 @@ static int phylink_bringup_phy(struct phylink *pl, struct phy_device *phy,
if (phy->is_c45 && config.rate_matching == RATE_MATCH_NONE &&
interface != PHY_INTERFACE_MODE_RXAUI &&
interface != PHY_INTERFACE_MODE_XAUI &&
- interface != PHY_INTERFACE_MODE_USXGMII)
+ interface != PHY_INTERFACE_MODE_USXGMII &&
+ interface != PHY_INTERFACE_MODE_10G_QXGMII)
config.interface = PHY_INTERFACE_MODE_NA;
else
config.interface = interface;
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 3cc52826f18e..e0af0378e2a1 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -125,6 +125,7 @@ extern const int phy_10gbit_features_array[1];
* @PHY_INTERFACE_MODE_10GKR: 10GBASE-KR - with Clause 73 AN
* @PHY_INTERFACE_MODE_QUSGMII: Quad Universal SGMII
* @PHY_INTERFACE_MODE_1000BASEKX: 1000Base-KX - with Clause 73 AN
+ * @PHY_INTERFACE_MODE_10G_QXGMII: 10G-QXGMII - 4 ports over 10G USXGMII
* @PHY_INTERFACE_MODE_MAX: Book keeping
*
* Describes the interface between the MAC and PHY.
@@ -165,6 +166,7 @@ typedef enum {
PHY_INTERFACE_MODE_10GKR,
PHY_INTERFACE_MODE_QUSGMII,
PHY_INTERFACE_MODE_1000BASEKX,
+ PHY_INTERFACE_MODE_10G_QXGMII,
PHY_INTERFACE_MODE_MAX,
} phy_interface_t;

@@ -286,6 +288,8 @@ static inline const char *phy_modes(phy_interface_t interface)
return "100base-x";
case PHY_INTERFACE_MODE_QUSGMII:
return "qusgmii";
+ case PHY_INTERFACE_MODE_10G_QXGMII:
+ return "10g-qxgmii";
default:
return "unknown";
}
diff --git a/include/linux/phylink.h b/include/linux/phylink.h
index d589f89c612c..d7e32c9f3ae1 100644
--- a/include/linux/phylink.h
+++ b/include/linux/phylink.h
@@ -614,6 +614,7 @@ static inline int phylink_get_link_timer_ns(phy_interface_t interface)
case PHY_INTERFACE_MODE_SGMII:
case PHY_INTERFACE_MODE_QSGMII:
case PHY_INTERFACE_MODE_USXGMII:
+ case PHY_INTERFACE_MODE_10G_QXGMII:
return 1600000;

case PHY_INTERFACE_MODE_1000BASEX:
--
2.42.0