net: dsa: tag_8021q: support up to 8 VLANs per port using sub-VLANs

[linux-2.6-microblaze.git] / net / dsa / tag_8021q.c

diff --git a/net/dsa/tag_8021q.c b/net/dsa/tag_8021q.c
index 3236fbb..3052da6 100644 (file)
--- a/net/dsa/tag_8021q.c
+++ b/net/dsa/tag_8021q.c
@@ -17,7 +17,7 @@
  *
  * | 11  | 10  |  9  |  8  |  7  |  6  |  5  |  4  |  3  |  2  |  1  |  0  |
  * +-----------+-----+-----------------+-----------+-----------------------+
- * |    DIR    | RSV |    SWITCH_ID    |    RSV    |          PORT         |
+ * |    DIR    | SVL |    SWITCH_ID    |  SUBVLAN  |          PORT         |
  * +-----------+-----+-----------------+-----------+-----------------------+
  *
  * DIR - VID[11:10]:
@@ -27,17 +27,24 @@
  *     These values make the special VIDs of 0, 1 and 4095 to be left
  *     unused by this coding scheme.
  *
- * RSV - VID[9]:
- *     To be used for further expansion of SWITCH_ID or for other purposes.
- *     Must be transmitted as zero and ignored on receive.
+ * SVL/SUBVLAN - { VID[9], VID[5:4] }:
+ *     Sub-VLAN encoding. Valid only when DIR indicates an RX VLAN.
+ *     * 0 (0b000): Field does not encode a sub-VLAN, either because
+ *     received traffic is untagged, PVID-tagged or because a second
+ *     VLAN tag is present after this tag and not inside of it.
+ *     * 1 (0b001): Received traffic is tagged with a VID value private
+ *     to the host. This field encodes the index in the host's lookup
+ *     table through which the value of the ingress VLAN ID can be
+ *     recovered.
+ *     * 2 (0b010): Field encodes a sub-VLAN.
+ *     ...
+ *     * 7 (0b111): Field encodes a sub-VLAN.
+ *     When DIR indicates a TX VLAN, SUBVLAN must be transmitted as zero
+ *     (by the host) and ignored on receive (by the switch).
  *
  * SWITCH_ID - VID[8:6]:
  *     Index of switch within DSA tree. Must be between 0 and 7.
  *
- * RSV - VID[5:4]:
- *     To be used for further expansion of PORT or for other purposes.
- *     Must be transmitted as zero and ignored on receive.
- *
  * PORT - VID[3:0]:
  *     Index of switch port. Must be between 0 and 15.
  */
@@ -54,6 +61,18 @@
 #define DSA_8021Q_SWITCH_ID(x)         (((x) << DSA_8021Q_SWITCH_ID_SHIFT) & \
                                                 DSA_8021Q_SWITCH_ID_MASK)
 
+#define DSA_8021Q_SUBVLAN_HI_SHIFT     9
+#define DSA_8021Q_SUBVLAN_HI_MASK      GENMASK(9, 9)
+#define DSA_8021Q_SUBVLAN_LO_SHIFT     4
+#define DSA_8021Q_SUBVLAN_LO_MASK      GENMASK(4, 3)
+#define DSA_8021Q_SUBVLAN_HI(x)                (((x) & GENMASK(2, 2)) >> 2)
+#define DSA_8021Q_SUBVLAN_LO(x)                ((x) & GENMASK(1, 0))
+#define DSA_8021Q_SUBVLAN(x)           \
+               (((DSA_8021Q_SUBVLAN_LO(x) << DSA_8021Q_SUBVLAN_LO_SHIFT) & \
+                 DSA_8021Q_SUBVLAN_LO_MASK) | \
+                ((DSA_8021Q_SUBVLAN_HI(x) << DSA_8021Q_SUBVLAN_HI_SHIFT) & \
+                 DSA_8021Q_SUBVLAN_HI_MASK))
+
 #define DSA_8021Q_PORT_SHIFT           0
 #define DSA_8021Q_PORT_MASK            GENMASK(3, 0)
 #define DSA_8021Q_PORT(x)              (((x) << DSA_8021Q_PORT_SHIFT) & \
@@ -79,6 +98,13 @@ u16 dsa_8021q_rx_vid(struct dsa_switch *ds, int port)
 }
 EXPORT_SYMBOL_GPL(dsa_8021q_rx_vid);
 
+u16 dsa_8021q_rx_vid_subvlan(struct dsa_switch *ds, int port, u16 subvlan)
+{
+       return DSA_8021Q_DIR_RX | DSA_8021Q_SWITCH_ID(ds->index) |
+              DSA_8021Q_PORT(port) | DSA_8021Q_SUBVLAN(subvlan);
+}
+EXPORT_SYMBOL_GPL(dsa_8021q_rx_vid_subvlan);
+
 /* Returns the decoded switch ID from the RX VID. */
 int dsa_8021q_rx_switch_id(u16 vid)
 {
@@ -93,6 +119,20 @@ int dsa_8021q_rx_source_port(u16 vid)
 }
 EXPORT_SYMBOL_GPL(dsa_8021q_rx_source_port);
 
+/* Returns the decoded subvlan from the RX VID. */
+u16 dsa_8021q_rx_subvlan(u16 vid)
+{
+       u16 svl_hi, svl_lo;
+
+       svl_hi = (vid & DSA_8021Q_SUBVLAN_HI_MASK) >>
+                DSA_8021Q_SUBVLAN_HI_SHIFT;
+       svl_lo = (vid & DSA_8021Q_SUBVLAN_LO_MASK) >>
+                DSA_8021Q_SUBVLAN_LO_SHIFT;
+
+       return (svl_hi << 2) | svl_lo;
+}
+EXPORT_SYMBOL_GPL(dsa_8021q_rx_subvlan);
+
 bool vid_is_dsa_8021q(u16 vid)
 {
        return ((vid & DSA_8021Q_DIR_MASK) == DSA_8021Q_DIR_RX ||