Merge branch 'dsa-lan9303-Learn-addresses-on-CPU-port-when-bridged'

Egil Hjelmeland says:

====================
net: dsa: lan9303: Learn addresses on CPU port when bridged

When CPU transmit directly to port using tag, the LAN9303 does not
learn MAC addresses received on the CPU port into the ALR table.
ALR learning is performed only when transmitting using ALR lookup.

Solution:
If the two external ports are bridged and the packet is not STP BPDU,
then use ALR lookup to allow ALR learning on CPU port.
Otherwise transmit directly to port with STP state override.

The first patch moves struct lan9303 to include/linux/dsa/lan9303.h in
order to prepare for the second patch.

Changes v1 -> v2:
 - new file: include/linux/dsa/lan9303.h instead of include/linux/lan9303.h
 - include linux/if_ether.h in include/linux/dsa/lan9303.h
 - renamed lan9303_tx_use_arl to lan9303_xmit_use_arl for consistency.
 - removed inline keyword to lan9303_xmit_use_arl
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

MAINTAINERS

@@ -9415,6 +9415,7 @@ M:	Florian Fainelli <f.fainelli@gmail.com>
 S:	Maintained
 F:	net/dsa/
 F:	include/net/dsa.h
+F:	include/linux/dsa/
 F:	drivers/net/dsa/
 
 NETWORKING [GENERAL]

drivers/net/dsa/lan9303.h

@@ -2,39 +2,7 @@
 #include <linux/device.h>
 #include <net/dsa.h>
 
-struct lan9303;
-
-struct lan9303_phy_ops {
-	/* PHY 1 and 2 access*/
-	int	(*phy_read)(struct lan9303 *chip, int port, int regnum);
-	int	(*phy_write)(struct lan9303 *chip, int port,
-			     int regnum, u16 val);
-};
-
-#define LAN9303_NUM_ALR_RECORDS 512
-struct lan9303_alr_cache_entry {
-	u8  mac_addr[ETH_ALEN];
-	u8  port_map;           /* Bitmap of ports. Zero if unused entry */
-	u8  stp_override;       /* non zero if set ALR_DAT1_AGE_OVERRID */
-};
-
-struct lan9303 {
-	struct device *dev;
-	struct regmap *regmap;
-	struct regmap_irq_chip_data *irq_data;
-	struct gpio_desc *reset_gpio;
-	u32 reset_duration; /* in [ms] */
-	bool phy_addr_sel_strap;
-	struct dsa_switch *ds;
-	struct mutex indirect_mutex; /* protect indexed register access */
-	const struct lan9303_phy_ops *ops;
-	bool is_bridged; /* true if port 1 and 2 are bridged */
-	u32 swe_port_state; /* remember SWE_PORT_STATE while not bridged */
-	/* LAN9303 do not offer reading specific ALR entry. Cache all
-	 * static entries in a flat table
-	 **/
-	struct lan9303_alr_cache_entry alr_cache[LAN9303_NUM_ALR_RECORDS];
-};
+#include <linux/dsa/lan9303.h>
 
 extern const struct regmap_access_table lan9303_register_set;
 extern const struct lan9303_phy_ops lan9303_indirect_phy_ops;

include/linux/dsa/lan9303.h

+/* Included by drivers/net/dsa/lan9303.h and net/dsa/tag_lan9303.c */
+#include <linux/if_ether.h>
+
+struct lan9303;
+
+struct lan9303_phy_ops {
+	/* PHY 1 and 2 access*/
+	int	(*phy_read)(struct lan9303 *chip, int port, int regnum);
+	int	(*phy_write)(struct lan9303 *chip, int port,
+			     int regnum, u16 val);
+};
+
+#define LAN9303_NUM_ALR_RECORDS 512
+struct lan9303_alr_cache_entry {
+	u8  mac_addr[ETH_ALEN];
+	u8  port_map;           /* Bitmap of ports. Zero if unused entry */
+	u8  stp_override;       /* non zero if set ALR_DAT1_AGE_OVERRID */
+};
+
+struct lan9303 {
+	struct device *dev;
+	struct regmap *regmap;
+	struct regmap_irq_chip_data *irq_data;
+	struct gpio_desc *reset_gpio;
+	u32 reset_duration; /* in [ms] */
+	bool phy_addr_sel_strap;
+	struct dsa_switch *ds;
+	struct mutex indirect_mutex; /* protect indexed register access */
+	const struct lan9303_phy_ops *ops;
+	bool is_bridged; /* true if port 1 and 2 are bridged */
+	u32 swe_port_state; /* remember SWE_PORT_STATE while not bridged */
+	/* LAN9303 do not offer reading specific ALR entry. Cache all
+	 * static entries in a flat table
+	 **/
+	struct lan9303_alr_cache_entry alr_cache[LAN9303_NUM_ALR_RECORDS];
+};

net/dsa/tag_lan9303.c

@@ -11,6 +11,7 @@
  * GNU General Public License for more details.
  *
  */
+#include <linux/dsa/lan9303.h>
 #include <linux/etherdevice.h>
 #include <linux/list.h>
 #include <linux/slab.h>
@@ -39,6 +40,23 @@
  */
 
 #define LAN9303_TAG_LEN 4
+# define LAN9303_TAG_TX_USE_ALR BIT(3)
+# define LAN9303_TAG_TX_STP_OVERRIDE BIT(4)
+#define eth_stp_addr eth_reserved_addr_base
+
+/* Decide whether to transmit using ALR lookup, or transmit directly to
+ * port using tag. ALR learning is performed only when using ALR lookup.
+ * If the two external ports are bridged and the packet is not STP BPDU,
+ * then use ALR lookup to allow ALR learning on CPU port.
+ * Otherwise transmit directly to port with STP state override.
+ * See also: lan9303_separate_ports() and lan9303.pdf 6.4.10.1
+ */
+static int lan9303_xmit_use_arl(struct dsa_port *dp, u8 *dest_addr)
+{
+	struct lan9303 *chip = dp->ds->priv;
+
+	return chip->is_bridged && !ether_addr_equal(dest_addr, eth_stp_addr);
+}
 
 static struct sk_buff *lan9303_xmit(struct sk_buff *skb, struct net_device *dev)
 {
@@ -62,7 +80,10 @@ static struct sk_buff *lan9303_xmit(struct sk_buff *skb, struct net_device *dev)
 
 	lan9303_tag = (u16 *)(skb->data + 2 * ETH_ALEN);
 	lan9303_tag[0] = htons(ETH_P_8021Q);
-	lan9303_tag[1] = htons(dp->index | BIT(4));
+	lan9303_tag[1] = lan9303_xmit_use_arl(dp, skb->data) ?
+				LAN9303_TAG_TX_USE_ALR :
+				dp->index | LAN9303_TAG_TX_STP_OVERRIDE;
+	lan9303_tag[1] = htons(lan9303_tag[1]);
 
 	return skb;
 }