From 6ba135d8c334a854cd163490bd587d4e034ce7c1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marek=20Beh=C3=BAn?= <kabel@kernel.org>
Date: Tue, 30 Nov 2021 18:01:46 +0100
Subject: [PATCH 03/26] net: dsa: mv88e6xxx: Fix application of erratum 4.8 for
 88E6393X
Git-commit: 21635d9203e1cf2b73b67e9a86059a62f62a3563
Patch-mainline: v5.16-rc4
References: git-fixes

According to SERDES scripts for 88E6393X, erratum 4.8 has to be applied
every time before SerDes is powered on.

Split the code for erratum 4.8 into separate function and call it in
mv88e6393x_serdes_power().

Fixes: de776d0d316f ("net: dsa: mv88e6xxx: add support for mv88e6393x family")
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
 drivers/net/dsa/mv88e6xxx/serdes.c | 53 ++++++++++++++++++++++++--------------
 1 file changed, 33 insertions(+), 20 deletions(-)

diff --git a/drivers/net/dsa/mv88e6xxx/serdes.c b/drivers/net/dsa/mv88e6xxx/serdes.c
index 6ea003678798..0658ee3b014c 100644
--- a/drivers/net/dsa/mv88e6xxx/serdes.c
+++ b/drivers/net/dsa/mv88e6xxx/serdes.c
@@ -1271,9 +1271,9 @@ void mv88e6390_serdes_get_regs(struct mv88e6xxx_chip *chip, int port, void *_p)
 	}
 }
 
-static int mv88e6393x_serdes_port_errata(struct mv88e6xxx_chip *chip, int lane)
+static int mv88e6393x_serdes_erratum_4_6(struct mv88e6xxx_chip *chip, int lane)
 {
-	u16 reg, pcs;
+	u16 reg;
 	int err;
 
 	/* mv88e6393x family errata 4.6:
@@ -1300,11 +1300,32 @@ static int mv88e6393x_serdes_port_errata(struct mv88e6xxx_chip *chip, int lane)
 		if (err)
 			return err;
 
-		err = mv88e6390_serdes_power_sgmii(chip, lane, false);
-		if (err)
-			return err;
+		return mv88e6390_serdes_power_sgmii(chip, lane, false);
 	}
 
+	return 0;
+}
+
+int mv88e6393x_serdes_setup_errata(struct mv88e6xxx_chip *chip)
+{
+	int err;
+
+	err = mv88e6393x_serdes_erratum_4_6(chip, MV88E6393X_PORT0_LANE);
+	if (err)
+		return err;
+
+	err = mv88e6393x_serdes_erratum_4_6(chip, MV88E6393X_PORT9_LANE);
+	if (err)
+		return err;
+
+	return mv88e6393x_serdes_erratum_4_6(chip, MV88E6393X_PORT10_LANE);
+}
+
+static int mv88e6393x_serdes_erratum_4_8(struct mv88e6xxx_chip *chip, int lane)
+{
+	u16 reg, pcs;
+	int err;
+
 	/* mv88e6393x family errata 4.8:
 	 * When a SERDES port is operating in 1000BASE-X or SGMII mode link may
 	 * not come up after hardware reset or software reset of SERDES core.
@@ -1334,29 +1355,21 @@ static int mv88e6393x_serdes_port_errata(struct mv88e6xxx_chip *chip, int lane)
 				      MV88E6393X_ERRATA_4_8_REG, reg);
 }
 
-int mv88e6393x_serdes_setup_errata(struct mv88e6xxx_chip *chip)
-{
-	int err;
-
-	err = mv88e6393x_serdes_port_errata(chip, MV88E6393X_PORT0_LANE);
-	if (err)
-		return err;
-
-	err = mv88e6393x_serdes_port_errata(chip, MV88E6393X_PORT9_LANE);
-	if (err)
-		return err;
-
-	return mv88e6393x_serdes_port_errata(chip, MV88E6393X_PORT10_LANE);
-}
-
 int mv88e6393x_serdes_power(struct mv88e6xxx_chip *chip, int port, int lane,
 			    bool on)
 {
 	u8 cmode = chip->ports[port].cmode;
+	int err;
 
 	if (port != 0 && port != 9 && port != 10)
 		return -EOPNOTSUPP;
 
+	if (on) {
+		err = mv88e6393x_serdes_erratum_4_8(chip, lane);
+		if (err)
+			return err;
+	}
+
 	switch (cmode) {
 	case MV88E6XXX_PORT_STS_CMODE_SGMII:
 	case MV88E6XXX_PORT_STS_CMODE_1000BASEX:
-- 
2.16.4