net: dsa: b53: implement port isolation support

Implement port isolation support via the Protected Ports register.

Protected ports can only communicate with unprotected ports, but not
with each other, matching the expected behaviour of isolated ports.

Tested on BCM963268BU.

Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://patch.msgid.link/20251013152834.100169-1-jonas.gorski@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c
index 2f846381d5a76273da60dede07a256c496a3fcf4..ad4990da9f7cff00d550373882d451dad41a16f9 100644 (file)
--- a/drivers/net/dsa/b53/b53_common.c
+++ b/drivers/net/dsa/b53/b53_common.c
@@ -632,6 +632,25 @@ static void b53_port_set_learning(struct b53_device *dev, int port,
        b53_write16(dev, B53_CTRL_PAGE, B53_DIS_LEARNING, reg);
 }
 
+static void b53_port_set_isolated(struct b53_device *dev, int port,
+                                 bool isolated)
+{
+       u8 offset;
+       u16 reg;
+
+       if (is5325(dev))
+               offset = B53_PROTECTED_PORT_SEL_25;
+       else
+               offset = B53_PROTECTED_PORT_SEL;
+
+       b53_read16(dev, B53_CTRL_PAGE, offset, &reg);
+       if (isolated)
+               reg |= BIT(port);
+       else
+               reg &= ~BIT(port);
+       b53_write16(dev, B53_CTRL_PAGE, offset, reg);
+}
+
 static void b53_eee_enable_set(struct dsa_switch *ds, int port, bool enable)
 {
        struct b53_device *dev = ds->priv;
@@ -652,6 +671,7 @@ int b53_setup_port(struct dsa_switch *ds, int port)
        b53_port_set_ucast_flood(dev, port, true);
        b53_port_set_mcast_flood(dev, port, true);
        b53_port_set_learning(dev, port, false);
+       b53_port_set_isolated(dev, port, false);
 
        /* Force all traffic to go to the CPU port to prevent the ASIC from
         * trying to forward to bridged ports on matching FDB entries, then
@@ -2318,7 +2338,7 @@ int b53_br_flags_pre(struct dsa_switch *ds, int port,
                     struct netlink_ext_ack *extack)
 {
        struct b53_device *dev = ds->priv;
-       unsigned long mask = (BR_FLOOD | BR_MCAST_FLOOD);
+       unsigned long mask = (BR_FLOOD | BR_MCAST_FLOOD | BR_ISOLATED);
 
        if (!is5325(dev))
                mask |= BR_LEARNING;
@@ -2343,6 +2363,9 @@ int b53_br_flags(struct dsa_switch *ds, int port,
        if (flags.mask & BR_LEARNING)
                b53_port_set_learning(ds->priv, port,
                                      !!(flags.val & BR_LEARNING));
+       if (flags.mask & BR_ISOLATED)
+               b53_port_set_isolated(ds->priv, port,
+                                     !!(flags.val & BR_ISOLATED));
 
        return 0;
 }

diff --git a/drivers/net/dsa/b53/b53_regs.h b/drivers/net/dsa/b53/b53_regs.h
index 309fe0e46dadf4cc3e3c4185e5f8053d386ea33f..c16b3e3e8227873d24c9cc48c79dc7f835404d9e 100644 (file)
--- a/drivers/net/dsa/b53/b53_regs.h
+++ b/drivers/net/dsa/b53/b53_regs.h
@@ -120,6 +120,10 @@
 #define B53_SWITCH_CTRL                        0x22
 #define  B53_MII_DUMB_FWDG_EN          BIT(6)
 
+/* Protected Port Selection (16 bit) */
+#define B53_PROTECTED_PORT_SEL         0x24
+#define B53_PROTECTED_PORT_SEL_25      0x26
+
 /* (16 bit) */
 #define B53_UC_FLOOD_MASK              0x32
 #define B53_MC_FLOOD_MASK              0x34