[PATCH net-next 1/2] net: dsa: bcm_sf2: Disallow port 5 to be a DSA CPU port

[Florian Fainelli]

While the switch driver is written such that port 5 or 8 could be CPU
ports, the use case on Broadcom STB chips is to use port 8 exclusively.
The platform firmware does make port 5 comply to a proper DSA CPU port
binding by specifiying an "ethernet" phandle. This is undesirable for
now until we have an user-space configuration mechanism (such as
devlink) which could support dynamically changing the port flavor at
run time.

Signed-off-by: Florian Fainelli <f.faine...@gmail.com>
---
 drivers/net/dsa/bcm_sf2.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/net/dsa/bcm_sf2.c b/drivers/net/dsa/bcm_sf2.c
index 723820603107..2bd52b03de38 100644
--- a/drivers/net/dsa/bcm_sf2.c
+++ b/drivers/net/dsa/bcm_sf2.c
@@ -457,6 +457,7 @@ static void bcm_sf2_identify_ports(struct bcm_sf2_priv 
*priv,
 {
        struct device_node *port;
        unsigned int port_num;
+       struct property *prop;
        phy_interface_t mode;
        int err;
 
@@ -483,6 +484,16 @@ static void bcm_sf2_identify_ports(struct bcm_sf2_priv 
*priv,
 
                if (of_property_read_bool(port, "brcm,use-bcm-hdr"))
                        priv->brcm_tag_mask |= 1 << port_num;
+
+               /* Ensure that port 5 is not picked up as a DSA CPU port
+                * flavour but a regular port instead. We should be using
+                * devlink to be able to set the port flavour.
+                */
+               if (port_num == 5 && priv->type == BCM7278_DEVICE_ID) {
+                       prop = of_find_property(port, "ethernet", NULL);
+                       if (prop)
+                               of_remove_property(port, prop);
+               }
        }
 }
 
-- 
2.25.1