Merge branch 'net-phy-bcm5481x-add-support-for-broadr-reach-mode'

Kamil Horák says:

====================
net: phy: bcm5481x: add support for BroadR-Reach mode

PATCH 1 - Add the 10baseT1BRR_Full link mode

PATCH 2 - Add the definitions of LRE registers, necessary to use
   BroadR-Reach modes on the BCM5481x PHY

PATCH 3 - Add brr-mode flag to switch between IEEE802.3 and BroadR-Reach

PATCH 4 - Implementation of the BroadR-Reach modes for the Broadcom
   PHYs
====================

Link: https://patch.msgid.link/20240712150709.3134474-1-kamilh@axis.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: kuba-moo

Documentation/devicetree/bindings/net/ethernet-phy.yaml

@@ -93,6 +93,14 @@ properties:
       the turn around line low at end of the control phase of the
       MDIO transaction.
 
+  brr-mode:
+    $ref: /schemas/types.yaml#/definitions/flag
+    description:
+      If set, indicates the network cable interface is an alternative one as
+      defined in the BroadR-Reach link mode specification under 1BR-100 and
+      1BR-10 names. The PHY must be configured to operate in BroadR-Reach mode
+      by software.
+
   clocks:
     maxItems: 1
     description:

drivers/net/phy/bcm-phy-lib.c

@@ -794,6 +794,49 @@ static int _bcm_phy_cable_test_get_status(struct phy_device *phydev,
 	return ret;
 }
 
+static int bcm_setup_lre_forced(struct phy_device *phydev)
+{
+	u16 ctl = 0;
+
+	phydev->pause = 0;
+	phydev->asym_pause = 0;
+
+	if (phydev->speed == SPEED_100)
+		ctl |= LRECR_SPEED100;
+
+	if (phydev->duplex != DUPLEX_FULL)
+		return -EOPNOTSUPP;
+
+	return phy_modify(phydev, MII_BCM54XX_LRECR, LRECR_SPEED100, ctl);
+}
+
+/**
+ * bcm_linkmode_adv_to_lre_adv_t - translate linkmode advertisement to LDS
+ * @advertising: the linkmode advertisement settings
+ * Return: LDS Auto-Negotiation Advertised Ability register value
+ *
+ * A small helper function that translates linkmode advertisement
+ * settings to phy LDS autonegotiation advertisements for the
+ * MII_BCM54XX_LREANAA register of Broadcom PHYs capable of LDS
+ */
+static u32 bcm_linkmode_adv_to_lre_adv_t(unsigned long *advertising)
+{
+	u32 result = 0;
+
+	if (linkmode_test_bit(ETHTOOL_LINK_MODE_10baseT1BRR_Full_BIT,
+			      advertising))
+		result |= LREANAA_10_1PAIR;
+	if (linkmode_test_bit(ETHTOOL_LINK_MODE_100baseT1_Full_BIT,
+			      advertising))
+		result |= LREANAA_100_1PAIR;
+	if (linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT, advertising))
+		result |= LRELPA_PAUSE;
+	if (linkmode_test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT, advertising))
+		result |= LRELPA_PAUSE_ASYM;
+
+	return result;
+}
+
 int bcm_phy_cable_test_start(struct phy_device *phydev)
 {
 	return _bcm_phy_cable_test_start(phydev, false);
@@ -1066,6 +1109,78 @@ int bcm_phy_led_brightness_set(struct phy_device *phydev,
 }
 EXPORT_SYMBOL_GPL(bcm_phy_led_brightness_set);
 
+int bcm_setup_lre_master_slave(struct phy_device *phydev)
+{
+	u16 ctl = 0;
+
+	switch (phydev->master_slave_set) {
+	case MASTER_SLAVE_CFG_MASTER_PREFERRED:
+	case MASTER_SLAVE_CFG_MASTER_FORCE:
+		ctl = LRECR_MASTER;
+		break;
+	case MASTER_SLAVE_CFG_SLAVE_PREFERRED:
+	case MASTER_SLAVE_CFG_SLAVE_FORCE:
+		break;
+	case MASTER_SLAVE_CFG_UNKNOWN:
+	case MASTER_SLAVE_CFG_UNSUPPORTED:
+		return 0;
+	default:
+		phydev_warn(phydev, "Unsupported Master/Slave mode\n");
+		return -EOPNOTSUPP;
+	}
+
+	return phy_modify_changed(phydev, MII_BCM54XX_LRECR, LRECR_MASTER, ctl);
+}
+EXPORT_SYMBOL_GPL(bcm_setup_lre_master_slave);
+
+int bcm_config_lre_aneg(struct phy_device *phydev, bool changed)
+{
+	int err;
+
+	if (genphy_config_eee_advert(phydev))
+		changed = true;
+
+	err = bcm_setup_lre_master_slave(phydev);
+	if (err < 0)
+		return err;
+	else if (err)
+		changed = true;
+
+	if (phydev->autoneg != AUTONEG_ENABLE)
+		return bcm_setup_lre_forced(phydev);
+
+	err = bcm_config_lre_advert(phydev);
+	if (err < 0)
+		return err;
+	else if (err)
+		changed = true;
+
+	return genphy_check_and_restart_aneg(phydev, changed);
+}
+EXPORT_SYMBOL_GPL(bcm_config_lre_aneg);
+
+/**
+ * bcm_config_lre_advert - sanitize and advertise Long-Distance Signaling
+ *  auto-negotiation parameters
+ * @phydev: target phy_device struct
+ * Return:  0 if the PHY's advertisement hasn't changed, < 0 on error,
+ *          > 0 if it has changed
+ *
+ * Writes MII_BCM54XX_LREANAA with the appropriate values. The values are to be
+ *   sanitized before, to make sure we only advertise what is supported.
+ *  The sanitization is done already in phy_ethtool_ksettings_set()
+ */
+int bcm_config_lre_advert(struct phy_device *phydev)
+{
+	u32 adv = bcm_linkmode_adv_to_lre_adv_t(phydev->advertising);
+
+	/* Setup BroadR-Reach mode advertisement */
+	return phy_modify_changed(phydev, MII_BCM54XX_LREANAA,
+				 LRE_ADVERTISE_ALL | LREANAA_PAUSE |
+				 LREANAA_PAUSE_ASYM, adv);
+}
+EXPORT_SYMBOL_GPL(bcm_config_lre_advert);
+
 MODULE_DESCRIPTION("Broadcom PHY Library");
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Broadcom Corporation");

drivers/net/phy/bcm-phy-lib.h

@@ -121,4 +121,8 @@ irqreturn_t bcm_phy_wol_isr(int irq, void *dev_id);
 int bcm_phy_led_brightness_set(struct phy_device *phydev,
 			       u8 index, enum led_brightness value);
 
+int bcm_setup_lre_master_slave(struct phy_device *phydev);
+int bcm_config_lre_aneg(struct phy_device *phydev, bool changed);
+int bcm_config_lre_advert(struct phy_device *phydev);
+
 #endif /* _LINUX_BCM_PHY_LIB_H */