5.4-stable review patch. If anyone has any objections, please let me know.
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From: Jonas Gorski jonas.gorski@gmail.com
[ Upstream commit b6a8a5477fe9bd6be2b594a88f82f8bba41e6d54 ]
There is no guarantee that the port state override registers have their default values, as not all switches support being reset via register or have a reset GPIO.
So when forcing port config, we need to make sure to clear all fields, which we currently do not do for the speed and flow control configuration. This can cause flow control stay enabled, or in the case of speed becoming an illegal value, e.g. configured for 1G (0x2), then setting 100M (0x1), results in 0x3 which is invalid.
For PORT_OVERRIDE_SPEED_2000M we need to make sure to only clear it on supported chips, as the bit can have different meanings on other chips, e.g. for BCM5389 this controls scanning PHYs for link/speed configuration.
Fixes: 5e004460f874 ("net: dsa: b53: Add helper to set link parameters") Signed-off-by: Jonas Gorski jonas.gorski@gmail.com Reviewed-by: Florian Fainelli florian.fainelli@broadcom.com Link: https://patch.msgid.link/20251101132807.50419-2-jonas.gorski@gmail.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/dsa/b53/b53_common.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c index dca23e0edb9a8..234ef7771ceef 100644 --- a/drivers/net/dsa/b53/b53_common.c +++ b/drivers/net/dsa/b53/b53_common.c @@ -1066,6 +1066,10 @@ static void b53_force_port_config(struct b53_device *dev, int port, else reg &= ~PORT_OVERRIDE_FULL_DUPLEX;
+ reg &= ~(0x3 << GMII_PO_SPEED_S); + if (is5301x(dev) || is58xx(dev)) + reg &= ~PORT_OVERRIDE_SPEED_2000M; + switch (speed) { case 2000: reg |= PORT_OVERRIDE_SPEED_2000M; @@ -1084,6 +1088,11 @@ static void b53_force_port_config(struct b53_device *dev, int port, return; }
+ if (is5325(dev)) + reg &= ~PORT_OVERRIDE_LP_FLOW_25; + else + reg &= ~(PORT_OVERRIDE_RX_FLOW | PORT_OVERRIDE_TX_FLOW); + if (rx_pause) { if (is5325(dev)) reg |= PORT_OVERRIDE_LP_FLOW_25;