net: mdio: add clause 73 to ethtool conversion helper

Add a helper to convert a clause 73 advertisement to an ethtool bitmap.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

include/linux/mdio.h

@@ -486,6 +486,45 @@ static inline u32 linkmode_adv_to_mii_10base_t1_t(unsigned long *adv)
 	return result;
 }
 
+/**
+ * mii_c73_mod_linkmode - convert a Clause 73 advertisement to linkmodes
+ * @adv: linkmode advertisement setting
+ * @lpa: array of three u16s containing the advertisement
+ *
+ * Convert an IEEE 802.3 Clause 73 advertisement to ethtool link modes.
+ */
+static inline void mii_c73_mod_linkmode(unsigned long *adv, u16 *lpa)
+{
+	linkmode_mod_bit(ETHTOOL_LINK_MODE_Pause_BIT,
+			 adv, lpa[0] & MDIO_AN_C73_0_PAUSE);
+	linkmode_mod_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
+			 adv, lpa[0] & MDIO_AN_C73_0_ASM_DIR);
+	linkmode_mod_bit(ETHTOOL_LINK_MODE_1000baseKX_Full_BIT,
+			 adv, lpa[1] & MDIO_AN_C73_1_1000BASE_KX);
+	linkmode_mod_bit(ETHTOOL_LINK_MODE_10000baseKX4_Full_BIT,
+			 adv, lpa[1] & MDIO_AN_C73_1_10GBASE_KX4);
+	linkmode_mod_bit(ETHTOOL_LINK_MODE_40000baseKR4_Full_BIT,
+			 adv, lpa[1] & MDIO_AN_C73_1_40GBASE_KR4);
+	linkmode_mod_bit(ETHTOOL_LINK_MODE_40000baseCR4_Full_BIT,
+			 adv, lpa[1] & MDIO_AN_C73_1_40GBASE_CR4);
+	/* 100GBASE_CR10 and 100GBASE_KP4 not implemented */
+	linkmode_mod_bit(ETHTOOL_LINK_MODE_100000baseKR4_Full_BIT,
+			 adv, lpa[1] & MDIO_AN_C73_1_100GBASE_KR4);
+	linkmode_mod_bit(ETHTOOL_LINK_MODE_100000baseCR4_Full_BIT,
+			 adv, lpa[1] & MDIO_AN_C73_1_100GBASE_CR4);
+	/* 25GBASE_R_S not implemented */
+	/* The 25GBASE_R bit can be used for 25Gbase KR or CR modes */
+	linkmode_mod_bit(ETHTOOL_LINK_MODE_25000baseKR_Full_BIT,
+			 adv, lpa[1] & MDIO_AN_C73_1_25GBASE_R);
+	linkmode_mod_bit(ETHTOOL_LINK_MODE_25000baseCR_Full_BIT,
+			 adv, lpa[1] & MDIO_AN_C73_1_25GBASE_R);
+	linkmode_mod_bit(ETHTOOL_LINK_MODE_10000baseKR_Full_BIT,
+			 adv, lpa[1] & MDIO_AN_C73_1_10GBASE_KR);
+	linkmode_mod_bit(ETHTOOL_LINK_MODE_2500baseX_Full_BIT,
+			 adv, lpa[2] & MDIO_AN_C73_2_2500BASE_KX);
+	/* 5GBASE_KR not implemented */
+}
+
 int __mdiobus_read(struct mii_bus *bus, int addr, u32 regnum);
 int __mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val);
 int __mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum,

include/uapi/linux/mdio.h

@@ -231,6 +231,30 @@
 #define MDIO_PMA_EXTABLE_BT1		0x0800	/* BASE-T1 ability */
 #define MDIO_PMA_EXTABLE_NBT		0x4000  /* 2.5/5GBASE-T ability */
 
+/* AN Clause 73 linkword */
+#define MDIO_AN_C73_0_S_MASK		GENMASK(4, 0)
+#define MDIO_AN_C73_0_E_MASK		GENMASK(9, 5)
+#define MDIO_AN_C73_0_PAUSE		BIT(10)
+#define MDIO_AN_C73_0_ASM_DIR		BIT(11)
+#define MDIO_AN_C73_0_C2		BIT(12)
+#define MDIO_AN_C73_0_RF		BIT(13)
+#define MDIO_AN_C73_0_ACK		BIT(14)
+#define MDIO_AN_C73_0_NP		BIT(15)
+#define MDIO_AN_C73_1_T_MASK		GENMASK(4, 0)
+#define MDIO_AN_C73_1_1000BASE_KX	BIT(5)
+#define MDIO_AN_C73_1_10GBASE_KX4	BIT(6)
+#define MDIO_AN_C73_1_10GBASE_KR	BIT(7)
+#define MDIO_AN_C73_1_40GBASE_KR4	BIT(8)
+#define MDIO_AN_C73_1_40GBASE_CR4	BIT(9)
+#define MDIO_AN_C73_1_100GBASE_CR10	BIT(10)
+#define MDIO_AN_C73_1_100GBASE_KP4	BIT(11)
+#define MDIO_AN_C73_1_100GBASE_KR4	BIT(12)
+#define MDIO_AN_C73_1_100GBASE_CR4	BIT(13)
+#define MDIO_AN_C73_1_25GBASE_R_S	BIT(14)
+#define MDIO_AN_C73_1_25GBASE_R		BIT(15)
+#define MDIO_AN_C73_2_2500BASE_KX	BIT(0)
+#define MDIO_AN_C73_2_5GBASE_KR		BIT(1)
+
 /* PHY XGXS lane state register. */
 #define MDIO_PHYXS_LNSTAT_SYNC0		0x0001
 #define MDIO_PHYXS_LNSTAT_SYNC1		0x0002