[PATCH v3 3/3] net: phy: bcm-phy-lib: Implement BroadR-Reach link modes

From: Kamil Horák - 2N
Date: Mon May 06 2024 - 10:42:32 EST


Implement single-pair BroadR-Reach modes on bcm5481x PHY by Broadcom.
Create set of functions alternative to IEEE 802.3 to handle configuration
of these modes on compatible Broadcom PHYs.

Signed-off-by: Kamil Horák - 2N <kamilh@xxxxxxxx>
---
drivers/net/phy/bcm-phy-lib.c | 122 ++++++++++++
drivers/net/phy/bcm-phy-lib.h | 4 +
drivers/net/phy/broadcom.c | 338 ++++++++++++++++++++++++++++++++--
3 files changed, 449 insertions(+), 15 deletions(-)

diff --git a/drivers/net/phy/bcm-phy-lib.c b/drivers/net/phy/bcm-phy-lib.c
index 876f28fd8256..9fa2a20e641f 100644
--- a/drivers/net/phy/bcm-phy-lib.c
+++ b/drivers/net/phy/bcm-phy-lib.c
@@ -794,6 +794,46 @@ static int _bcm_phy_cable_test_get_status(struct phy_device *phydev,
return ret;
}

+static int bcm_setup_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_mii_adv_t
+ * @advertising: the linkmode advertisement settings
+ *
+ * A small helper function that translates linkmode advertisement
+ * settings to phy autonegotiation advertisements for the
+ * MII_BCM54XX_LREANAA register.
+ */
+static inline u32 bcm_linkmode_adv_to_mii_adv_t(unsigned long *advertising)
+{
+ u32 result = 0;
+
+ if (linkmode_test_bit(ETHTOOL_LINK_MODE_1BR10_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 +1106,88 @@ int bcm_phy_led_brightness_set(struct phy_device *phydev,
}
EXPORT_SYMBOL_GPL(bcm_phy_led_brightness_set);

+int bcm_setup_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_master_slave);
+
+int bcm_config_aneg(struct phy_device *phydev, bool changed)
+{
+ int err;
+
+ if (genphy_config_eee_advert(phydev))
+ changed = true;
+
+ err = bcm_setup_master_slave(phydev);
+ if (err < 0)
+ return err;
+ else if (err)
+ changed = true;
+
+ if (phydev->autoneg != AUTONEG_ENABLE)
+ return bcm_setup_forced(phydev);
+
+ err = bcm_config_advert(phydev);
+ if (err < 0) /* error */
+ return err;
+ else if (err)
+ changed = true;
+
+ return genphy_check_and_restart_aneg(phydev, changed);
+}
+EXPORT_SYMBOL_GPL(bcm_config_aneg);
+
+/**
+ * bcm_config_advert - sanitize and advertise auto-negotiation parameters
+ * @phydev: target phy_device struct
+ *
+ * Description: Writes MII_BCM54XX_LREANAA with the appropriate values,
+ * after sanitizing the values to make sure we only advertise
+ * what is supported. Returns < 0 on error, 0 if the PHY's advertisement
+ * hasn't changed, and > 0 if it has changed.
+ */
+int bcm_config_advert(struct phy_device *phydev)
+{
+ int err;
+ u32 adv;
+
+ /* Only allow advertising what this PHY supports */
+ linkmode_and(phydev->advertising, phydev->advertising,
+ phydev->supported);
+
+ adv = bcm_linkmode_adv_to_mii_adv_t(phydev->advertising);
+
+ /* Setup BroadR-Reach mode advertisement */
+ err = phy_modify_changed(phydev, MII_BCM54XX_LREANAA,
+ LRE_ADVERTISE_ALL | LREANAA_PAUSE |
+ LREANAA_PAUSE_ASYM, adv);
+
+ if (err < 0)
+ return err;
+
+ return err > 0 ? 1 : 0;
+}
+EXPORT_SYMBOL_GPL(bcm_config_advert);
+
MODULE_DESCRIPTION("Broadcom PHY Library");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Broadcom Corporation");
diff --git a/drivers/net/phy/bcm-phy-lib.h b/drivers/net/phy/bcm-phy-lib.h
index b52189e45a84..0f6d06c0b7af 100644
--- a/drivers/net/phy/bcm-phy-lib.h
+++ b/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_master_slave(struct phy_device *phydev);
+int bcm_config_aneg(struct phy_device *phydev, bool changed);
+int bcm_config_advert(struct phy_device *phydev);
+
#endif /* _LINUX_BCM_PHY_LIB_H */
diff --git a/drivers/net/phy/broadcom.c b/drivers/net/phy/broadcom.c
index 370e4ed45098..2d8898fd2228 100644
--- a/drivers/net/phy/broadcom.c
+++ b/drivers/net/phy/broadcom.c
@@ -553,18 +553,46 @@ static int bcm54810_write_mmd(struct phy_device *phydev, int devnum, u16 regnum,
return -EOPNOTSUPP;
}

-static int bcm54811_config_init(struct phy_device *phydev)
+static int bcm5481x_get_brrmode(struct phy_device *phydev, u8 *data)
{
- int err, reg;
+ int reg;

- /* Disable BroadR-Reach function. */
reg = bcm_phy_read_exp(phydev, BCM54810_EXP_BROADREACH_LRE_MISC_CTL);
- reg &= ~BCM54810_EXP_BROADREACH_LRE_MISC_CTL_EN;
- err = bcm_phy_write_exp(phydev, BCM54810_EXP_BROADREACH_LRE_MISC_CTL,
- reg);
- if (err < 0)
+
+ *data = (reg & BCM54810_EXP_BROADREACH_LRE_MISC_CTL_EN) ?
+ ETHTOOL_PHY_BRR_MODE_ON : ETHTOOL_PHY_BRR_MODE_OFF;
+
+ return 0;
+}
+
+static int bcm5481x_set_brrmode(struct phy_device *phydev, u8 on)
+{
+ int reg;
+ int err;
+
+ reg = bcm_phy_read_exp(phydev, BCM54810_EXP_BROADREACH_LRE_MISC_CTL);
+
+ if (on)
+ reg |= BCM54810_EXP_BROADREACH_LRE_MISC_CTL_EN;
+ else
+ reg &= ~BCM54810_EXP_BROADREACH_LRE_MISC_CTL_EN;
+
+ err = bcm_phy_write_exp(phydev, BCM54810_EXP_BROADREACH_LRE_MISC_CTL, reg);
+ if (err)
return err;

+ /* Ensure LRE or IEEE register set is accessed according to the brr on/off,
+ * thus set the override
+ */
+ return bcm_phy_write_exp(phydev, BCM54811_EXP_BROADREACH_LRE_OVERLAY_CTL,
+ BCM54811_EXP_BROADREACH_LRE_OVERLAY_CTL_EN |
+ on ? 0 : BCM54811_EXP_BROADREACH_LRE_OVERLAY_CTL_OVERRIDE_VAL);
+}
+
+static int bcm54811_config_init(struct phy_device *phydev)
+{
+ int err, reg;
+
err = bcm54xx_config_init(phydev);

/* Enable CLK125 MUX on LED4 if ref clock is enabled. */
@@ -576,18 +604,16 @@ static int bcm54811_config_init(struct phy_device *phydev)
return err;
}

- return err;
+ /* Configure BroadR-Reach function. */
+ return bcm5481x_set_brrmode(phydev, ETHTOOL_PHY_BRR_MODE_OFF);
}

-static int bcm5481_config_aneg(struct phy_device *phydev)
+static int bcm5481x_config_delay_swap(struct phy_device *phydev)
{
struct device_node *np = phydev->mdio.dev.of_node;
- int ret;
-
- /* Aneg firstly. */
- ret = genphy_config_aneg(phydev);
+ int ret = 0;

- /* Then we can set up the delay. */
+ /* Set up the delay. */
bcm54xx_config_clock_delay(phydev);

if (of_property_read_bool(np, "enet-phy-lane-swap")) {
@@ -601,6 +627,56 @@ static int bcm5481_config_aneg(struct phy_device *phydev)
return ret;
}

+static int bcm5481_config_aneg(struct phy_device *phydev)
+{
+ int ret;
+ u8 brr_mode;
+
+ /* Aneg firstly. */
+ ret = bcm5481x_get_brrmode(phydev, &brr_mode);
+ if (ret)
+ return ret;
+
+ if (brr_mode == ETHTOOL_PHY_BRR_MODE_ON)
+ ret = bcm_config_aneg(phydev, false);
+ else
+ ret = genphy_config_aneg(phydev);
+
+ if (ret)
+ return ret;
+
+ /* Then we can set up the delay and swap. */
+ return bcm5481x_config_delay_swap(phydev);
+}
+
+static int bcm54811_config_aneg(struct phy_device *phydev)
+{
+ int ret;
+ u8 brr_mode;
+
+ /* Aneg firstly. */
+ ret = bcm5481x_get_brrmode(phydev, &brr_mode);
+ if (ret)
+ return ret;
+
+ if (brr_mode == ETHTOOL_PHY_BRR_MODE_ON) {
+ /* BCM54811 is only capable of autonegotiation in IEEE mode */
+ if (phydev->autoneg)
+ return -EOPNOTSUPP;
+
+ ret = bcm_config_aneg(phydev, false);
+
+ } else {
+ ret = genphy_config_aneg(phydev);
+ }
+
+ if (ret)
+ return ret;
+
+ /* Then we can set up the delay and swap. */
+ return bcm5481x_config_delay_swap(phydev);
+}
+
struct bcm54616s_phy_priv {
bool mode_1000bx_en;
};
@@ -1062,6 +1138,234 @@ static void bcm54xx_link_change_notify(struct phy_device *phydev)
bcm_phy_write_exp(phydev, MII_BCM54XX_EXP_EXP08, ret);
}

+static int bcm54811_read_abilities(struct phy_device *phydev)
+{
+ int val, err;
+ int i;
+ static const int modes_array[] = {ETHTOOL_LINK_MODE_100baseT1_Full_BIT,
+ ETHTOOL_LINK_MODE_1BR10_BIT,
+ ETHTOOL_LINK_MODE_1000baseT_Full_BIT,
+ ETHTOOL_LINK_MODE_1000baseX_Full_BIT,
+ ETHTOOL_LINK_MODE_1000baseT_Half_BIT,
+ ETHTOOL_LINK_MODE_100baseT_Full_BIT,
+ ETHTOOL_LINK_MODE_100baseT_Half_BIT,
+ ETHTOOL_LINK_MODE_10baseT_Full_BIT,
+ ETHTOOL_LINK_MODE_10baseT_Half_BIT};
+
+ u8 brr_mode;
+
+ for (i = 0; i < ARRAY_SIZE(modes_array); i++)
+ linkmode_clear_bit(modes_array[i], phydev->supported);
+
+ err = bcm5481x_get_brrmode(phydev, &brr_mode);
+
+ if (err)
+ return err;
+
+ if (brr_mode == ETHTOOL_PHY_BRR_MODE_ON) {
+ linkmode_set_bit_array(phy_basic_ports_array,
+ ARRAY_SIZE(phy_basic_ports_array),
+ phydev->supported);
+
+ val = phy_read(phydev, MII_BCM54XX_LRESR);
+ if (val < 0)
+ return val;
+
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_Autoneg_BIT,
+ phydev->supported, 1);
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_100baseT1_Full_BIT,
+ phydev->supported,
+ val & LRESR_100_1PAIR);
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_1BR10_BIT,
+ phydev->supported,
+ val & LRESR_10_1PAIR);
+ } else {
+ return genphy_read_abilities(phydev);
+ }
+
+ return err;
+}
+
+static int bcm5481x_get_tunable(struct phy_device *phydev,
+ struct ethtool_tunable *tuna, void *data)
+{
+ switch (tuna->id) {
+ case ETHTOOL_PHY_BRR_MODE:
+ return bcm5481x_get_brrmode(phydev, data);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int bcm5481x_set_tunable(struct phy_device *phydev,
+ struct ethtool_tunable *tuna, const void *data)
+{
+ int res;
+
+ switch (tuna->id) {
+ case ETHTOOL_PHY_BRR_MODE:
+ res = bcm5481x_set_brrmode(phydev, *(const u8 *)data);
+ if (res >= 0)
+ res = bcm54811_read_abilities(phydev);
+ break;
+ default:
+ res = -EOPNOTSUPP;
+ }
+
+ return res;
+}
+
+static int bcm_read_master_slave(struct phy_device *phydev)
+{
+ int cfg, state;
+ int val;
+
+ /* In BroadR-Reach mode we are always capable of master-slave
+ * and there is no preferred master or slave configuration
+ */
+ phydev->master_slave_get = MASTER_SLAVE_CFG_UNKNOWN;
+ phydev->master_slave_state = MASTER_SLAVE_STATE_UNKNOWN;
+
+ val = phy_read(phydev, MII_BCM54XX_LRECR);
+ if (val < 0)
+ return val;
+
+ if ((val & LRECR_LDSEN) == 0) {
+ if (val & LRECR_MASTER)
+ cfg = MASTER_SLAVE_CFG_MASTER_FORCE;
+ else
+ cfg = MASTER_SLAVE_CFG_SLAVE_FORCE;
+ }
+
+ val = phy_read(phydev, MII_BCM54XX_LRELDSE);
+ if (val < 0)
+ return val;
+
+ if (val & LDSE_MASTER)
+ state = MASTER_SLAVE_STATE_MASTER;
+ else
+ state = MASTER_SLAVE_STATE_SLAVE;
+
+ phydev->master_slave_get = cfg;
+ phydev->master_slave_state = state;
+
+ return 0;
+}
+
+/* Read LDS Link Partner Ability in BroadR-Reach mode */
+static int bcm_read_lpa(struct phy_device *phydev)
+{
+ int i, lrelpa;
+
+ if (phydev->autoneg != AUTONEG_ENABLE) {
+ if (!phydev->autoneg_complete) {
+ /* aneg not yet done, reset all relevant bits */
+ static int br_bits[] = { ETHTOOL_LINK_MODE_Autoneg_BIT,
+ ETHTOOL_LINK_MODE_Pause_BIT,
+ ETHTOOL_LINK_MODE_Asym_Pause_BIT,
+ ETHTOOL_LINK_MODE_1BR10_BIT,
+ ETHTOOL_LINK_MODE_100baseT1_Full_BIT };
+ for (i = 0; i < ARRAY_SIZE(br_bits); i++)
+ linkmode_clear_bit(br_bits[i], phydev->lp_advertising);
+
+ return 0;
+ }
+
+ /* Long-Distance-Signalling Link Partner Ability */
+ lrelpa = phy_read(phydev, MII_BCM54XX_LRELPA);
+ if (lrelpa < 0)
+ return lrelpa;
+
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
+ phydev->lp_advertising, lrelpa & LRELPA_PAUSE_ASYM);
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_Pause_BIT,
+ phydev->lp_advertising, lrelpa & LRELPA_PAUSE);
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_100baseT1_Full_BIT,
+ phydev->lp_advertising, lrelpa & LRELPA_100_1PAIR);
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_1BR10_BIT,
+ phydev->lp_advertising, lrelpa & LRELPA_10_1PAIR);
+ } else {
+ linkmode_zero(phydev->lp_advertising);
+ }
+
+ return 0;
+}
+
+static int bcm_read_status_fixed(struct phy_device *phydev)
+{
+ int lrecr = phy_read(phydev, MII_BCM54XX_LRECR);
+
+ if (lrecr < 0)
+ return lrecr;
+
+ phydev->duplex = DUPLEX_FULL;
+
+ if (lrecr & LRECR_SPEED100)
+ phydev->speed = SPEED_100;
+ else
+ phydev->speed = SPEED_10;
+
+ return 0;
+}
+
+static int bcm54811_read_status(struct phy_device *phydev)
+{
+ int err;
+ u8 brr_mode;
+
+ err = bcm5481x_get_brrmode(phydev, &brr_mode);
+
+ if (err)
+ return err;
+
+ if (brr_mode == ETHTOOL_PHY_BRR_MODE_ON) {
+ /* Get the status in BroadRReach mode just like genphy_read_status
+ * does in normal mode
+ */
+
+ int err, old_link = phydev->link;
+
+ /* Update the link, but return if there was an error
+ * genphy_update_link() functions equally on IEEE and LRE
+ * register set
+ */
+
+ err = genphy_update_link(phydev);
+ if (err)
+ return err;
+
+ /* why bother the PHY if nothing can have changed */
+ if (phydev->autoneg == AUTONEG_ENABLE && old_link && phydev->link)
+ return 0;
+
+ phydev->speed = SPEED_UNKNOWN;
+ phydev->duplex = DUPLEX_UNKNOWN;
+ phydev->pause = 0;
+ phydev->asym_pause = 0;
+
+ err = bcm_read_master_slave(phydev);
+ if (err < 0)
+ return err;
+
+ /* Read LDS Link Partner Ability */
+ err = bcm_read_lpa(phydev);
+ if (err < 0)
+ return err;
+
+ if (phydev->autoneg == AUTONEG_ENABLE && phydev->autoneg_complete) {
+ phy_resolve_aneg_linkmode(phydev);
+ } else if (phydev->autoneg == AUTONEG_DISABLE) {
+ err = bcm_read_status_fixed(phydev);
+ if (err < 0)
+ return err;
+ }
+ } else {
+ err = genphy_read_status(phydev);
+ }
+
+ return err;
+}
+
static struct phy_driver broadcom_drivers[] = {
{
.phy_id = PHY_ID_BCM5411,
@@ -1212,9 +1516,13 @@ static struct phy_driver broadcom_drivers[] = {
.get_stats = bcm54xx_get_stats,
.probe = bcm54xx_phy_probe,
.config_init = bcm54811_config_init,
- .config_aneg = bcm5481_config_aneg,
+ .config_aneg = bcm54811_config_aneg,
.config_intr = bcm_phy_config_intr,
.handle_interrupt = bcm_phy_handle_interrupt,
+ .read_status = bcm54811_read_status,
+ .get_tunable = bcm5481x_get_tunable,
+ .set_tunable = bcm5481x_set_tunable,
+ .get_features = bcm54811_read_abilities,
.suspend = bcm54xx_suspend,
.resume = bcm54xx_resume,
.link_change_notify = bcm54xx_link_change_notify,
--
2.39.2