Merge branch 'net-pcs-xpcs-cleanups-for-clause-73-support'

Russell King says:

====================
net: pcs: xpcs: cleanups for clause 73 support

This series cleans up xpcs code, moving much of the clause 73 code
out of the driver into places where others can make use of it.

Specifically, we add a helper to convert a clause 73 advertisement
to ethtool link modes to mdio.h, and a helper to resolve the clause
73 negotiation state to phylink, which includes the pause modes.

In doing this cleanup, several issues were identified with the
original xpcs implementation:

1) it masks the link partner advertisement with its own advertisement
   so userspace can't see what the full link partner advertisement
   was.
2) it was always setting pause modes irrespective of the advertisements
   on either end of the link.
3) it was reading the STAT1 registers multiple times. Reading STAT1
   has the side effect of unlatching the link-down status, so
   multiple reads should be avoided.

This patch series addresses the first two first by addressing the
issues, and then by moving over to the new helpers. The third issue
is solved by restructuring the xpcs code.
====================

Link: https://lore.kernel.org/r/ZGyR/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

2 files changed, 41 insertions, 0 deletions

diff --git a/include/linux/mdio.h b/include/linux/mdio.h
index 27013d6bf24a..0670cc6e067c 100644
--- a/include/linux/mdio.h
+++ b/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,
diff --git a/include/linux/phylink.h b/include/linux/phylink.h
index bb782f05ad08..0cf07d7d11b8 100644
--- a/include/linux/phylink.h
+++ b/include/linux/phylink.h
@@ -656,6 +656,8 @@ int phylink_mii_c22_pcs_config(struct mdio_device *pcs, unsigned int mode,
 			       const unsigned long *advertising);
 void phylink_mii_c22_pcs_an_restart(struct mdio_device *pcs);
 
+void phylink_resolve_c73(struct phylink_link_state *state);
+
 void phylink_mii_c45_pcs_get_state(struct mdio_device *pcs,
 				   struct phylink_link_state *state);