netdev - [PATCH net-next 2/2] net: dsa :mv88e6xxx: Disable unused ports

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed,  1 May 2019 00:08:31 +0200
From:   Andrew Lunn <andrew@...n.ch>
To:     David Miller <davem@...emloft.net>
Cc:     netdev <netdev@...r.kernel.org>,
        Vivien Didelot <vivien.didelot@...il.com>,
        Andrew Lunn <andrew@...n.ch>
Subject: [PATCH net-next 2/2] net: dsa :mv88e6xxx: Disable unused ports

If the NO_CPU strap is set, the switch starts in 'dumb hub' mode, with
all ports enable. Ports which are then actively used are reconfigured
as required when the driver starts. However unused ports are left
alone. Change this to disable them, and turn off any SERDES
interface. This could save some power and so reduce the temperature a
bit.

Signed-off-by: Andrew Lunn <andrew@...n.ch>
---
 drivers/net/dsa/mv88e6xxx/chip.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index dc891d83610e..46020fe1b5e7 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -2599,8 +2599,18 @@ static int mv88e6xxx_setup(struct dsa_switch *ds)
 
 	/* Setup Switch Port Registers */
 	for (i = 0; i < mv88e6xxx_num_ports(chip); i++) {
-		if (dsa_is_unused_port(ds, i))
+		if (dsa_is_unused_port(ds, i)) {
+			err = mv88e6xxx_port_set_state(chip, i,
+						       BR_STATE_DISABLED);
+			if (err)
+				goto unlock;
+
+			err = mv88e6xxx_serdes_power(chip, i, false);
+			if (err)
+				goto unlock;
+
 			continue;
+		}
 
 		err = mv88e6xxx_setup_port(chip, i);
 		if (err)
-- 
2.20.1