This is a note to let you know that I've just added the patch titled net: dsa: mv88e6xxx: Update mv88e6393x serdes errata to the 5.13-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-dsa-mv88e6xxx-update-mv88e6393x-serdes-errata.patch and it can be found in the queue-5.13 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 57c218c6ba9b232332a97fd35fa1a928274938a3 Author: Nathan Rossi <nathan.rossi@xxxxxxxx> Date: Tue Aug 24 06:44:13 2021 +0000 net: dsa: mv88e6xxx: Update mv88e6393x serdes errata [ Upstream commit 3b0720ba00a7413997ad331838d22c81f252556a ] In early erratas this issue only covered port 0 when changing from [x]MII (rev A 3.6). In subsequent errata versions this errata changed to cover the additional "Hardware reset in CPU managed mode" condition, and removed the note specifying that it only applied to port 0. In designs where the device is configured with CPU managed mode (CPU_MGD), on reset all SERDES ports (p0, p9, p10) have a stuck power down bit and require this initial power up procedure. As such apply this errata to all three SERDES ports of the mv88e6393x. Signed-off-by: Nathan Rossi <nathan.rossi@xxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/dsa/mv88e6xxx/serdes.c b/drivers/net/dsa/mv88e6xxx/serdes.c index b1d46dd8eaab..6ea003678798 100644 --- a/drivers/net/dsa/mv88e6xxx/serdes.c +++ b/drivers/net/dsa/mv88e6xxx/serdes.c @@ -1277,15 +1277,16 @@ static int mv88e6393x_serdes_port_errata(struct mv88e6xxx_chip *chip, int lane) int err; /* mv88e6393x family errata 4.6: - * Cannot clear PwrDn bit on SERDES on port 0 if device is configured - * CPU_MGD mode or P0_mode is configured for [x]MII. - * Workaround: Set Port0 SERDES register 4.F002 bit 5=0 and bit 15=1. + * Cannot clear PwrDn bit on SERDES if device is configured CPU_MGD + * mode or P0_mode is configured for [x]MII. + * Workaround: Set SERDES register 4.F002 bit 5=0 and bit 15=1. * * It seems that after this workaround the SERDES is automatically * powered up (the bit is cleared), so power it down. */ - if (lane == MV88E6393X_PORT0_LANE) { - err = mv88e6390_serdes_read(chip, MV88E6393X_PORT0_LANE, + if (lane == MV88E6393X_PORT0_LANE || lane == MV88E6393X_PORT9_LANE || + lane == MV88E6393X_PORT10_LANE) { + err = mv88e6390_serdes_read(chip, lane, MDIO_MMD_PHYXS, MV88E6393X_SERDES_POC, ®); if (err)