net: dsa: bcm_sf2: Allow non-IMP ports to have Broadcom tags enabled

Parse the "brcm,use-bcm-hdr" boolean property during ports
identification to fill a bitmask of ports that should have Broadcom tags
enabled. This is needed in some configurations where per-packet metadata
can be exchanged using Broadcom tags between the switch and an on-chip
acceleration device.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/brcm,bcm7445-switch-v4.0.txt

@@ -41,6 +41,13 @@ Optional properties:
   Admission Control Block supports reporting the number of packets in-flight in a
   switch queue
 
+Port subnodes:
+
+Optional properties:
+
+- brcm,use-bcm-hdr: boolean property, if present, indicates that the switch
+  port has Broadcom tags enabled (per-packet metadata)
+
 Example:
 
 switch_top@f0b00000 {
@@ -114,6 +121,7 @@ switch_top@f0b00000 {
 			port@0 {
 				label = "gphy";
 				reg = <0>;
+				brcm,use-bcm-hdr;
 			};
 			...
 		};

drivers/net/dsa/bcm_sf2.c

@@ -236,6 +236,10 @@ static int bcm_sf2_port_setup(struct dsa_switch *ds, int port,
 	reg &= ~P_TXQ_PSM_VDD(port);
 	core_writel(priv, reg, CORE_MEM_PSM_VDD_CTRL);
 
+	/* Enable Broadcom tags for that port if requested */
+	if (priv->brcm_tag_mask & BIT(port))
+		bcm_sf2_brcm_hdr_setup(priv, port);
+
 	/* Clear the Rx and Tx disable bits and set to no spanning tree */
 	core_writel(priv, 0, CORE_G_PCTL_PORT(port));
 
@@ -515,6 +519,9 @@ static void bcm_sf2_identify_ports(struct bcm_sf2_priv *priv,
 
 		if (mode == PHY_INTERFACE_MODE_MOCA)
 			priv->moca_port = port_num;
+
+		if (of_property_read_bool(port, "brcm,use-bcm-hdr"))
+			priv->brcm_tag_mask |= 1 << port_num;
 	}
 }
 

drivers/net/dsa/bcm_sf2.h

@@ -100,6 +100,9 @@ struct bcm_sf2_priv {
 	struct device_node		*master_mii_dn;
 	struct mii_bus			*slave_mii_bus;
 	struct mii_bus			*master_mii_bus;
+
+	/* Bitmask of ports needing BRCM tags */
+	unsigned int			brcm_tag_mask;
 };
 
 static inline struct bcm_sf2_priv *bcm_sf2_to_priv(struct dsa_switch *ds)