[PATCH stable 4.14 v2] net: dsa: bcm_sf2: force pause link settings

[Florian Fainelli <f.fainelli@gmail.com>]

From: Doug Berger <opendmb@gmail.com>

commit 7c97bc0128b2eecc703106112679a69d446d1a12 upstream

The pause settings reported by the PHY should also be applied to the
GMII port status override otherwise the switch will not generate pause
frames towards the link partner despite the advertisement saying
otherwise.

Fixes: 246d7f773c13 ("net: dsa: add Broadcom SF2 switch driver")
Signed-off-by: Doug Berger <opendmb@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20220623030204.1966851-1-f.fainelli@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
Changes in v2:

- use both local and remote advertisement to determine when to apply
  flow control settings

 drivers/net/dsa/bcm_sf2.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/net/dsa/bcm_sf2.c b/drivers/net/dsa/bcm_sf2.c
index 11a72c4cbb92..42b4f49c9f47 100644
--- a/drivers/net/dsa/bcm_sf2.c
+++ b/drivers/net/dsa/bcm_sf2.c
@@ -625,7 +625,9 @@ static void bcm_sf2_sw_adjust_link(struct dsa_switch *ds, int port,
 	struct bcm_sf2_priv *priv = bcm_sf2_to_priv(ds);
 	struct ethtool_eee *p = &priv->port_sts[port].eee;
 	u32 id_mode_dis = 0, port_mode;
+	u16 lcl_adv = 0, rmt_adv = 0;
 	const char *str = NULL;
+	u8 flowctrl = 0;
 	u32 reg, offset;
 
 	if (priv->type == BCM7445_DEVICE_ID)
@@ -697,10 +699,24 @@ static void bcm_sf2_sw_adjust_link(struct dsa_switch *ds, int port,
 		break;
 	}
 
+	if (phydev->pause)
+		rmt_adv = LPA_PAUSE_CAP;
+	if (phydev->asym_pause)
+		rmt_adv |= LPA_PAUSE_ASYM;
+	if (phydev->advertising & ADVERTISED_Pause)
+		lcl_adv = ADVERTISE_PAUSE_CAP;
+	if (phydev->advertising & ADVERTISED_Asym_Pause)
+		lcl_adv |= ADVERTISE_PAUSE_ASYM;
+	flowctrl = mii_resolve_flowctrl_fdx(lcl_adv, rmt_adv);
+
 	if (phydev->link)
 		reg |= LINK_STS;
 	if (phydev->duplex == DUPLEX_FULL)
 		reg |= DUPLX_MODE;
+	if (flowctrl & FLOW_CTRL_TX)
+		reg |= TXFLOW_CNTL;
+	if (flowctrl & FLOW_CTRL_RX)
+		reg |= RXFLOW_CNTL;
 
 	core_writel(priv, reg, offset);
 
-- 
2.25.1