[PATCH net-next 12/17] net: dsa: sja1105: Add support for VLAN operations

From: Vladimir Oltean
Date: Sun Mar 31 2019 - 13:44:00 EST


VLAN filtering cannot be properly disabled in SJA1105. So in order to
emulate the "no VLAN awareness" behavior (not dropping traffic that is
tagged with a VID that isn't configured on the port), we need to hack
another switch feature: programmable TPID (which is 0x8100 for 802.1Q).
We are reprogramming the TPID to a bogus value (ETH_P_EDSA) which leaves
the switch thinking that all traffic is untagged, and therefore accepts
it.

Under a vlan_filtering bridge, the proper TPID of ETH_P_8021Q is
installed again, and the switch starts identifying 802.1Q-tagged
traffic.

Signed-off-by: Vladimir Oltean <olteanv@xxxxxxxxx>
Reviewed-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
drivers/net/dsa/sja1105/sja1105_main.c | 260 +++++++++++++++++-
.../net/dsa/sja1105/sja1105_static_config.c | 38 +++
.../net/dsa/sja1105/sja1105_static_config.h | 3 +
3 files changed, 299 insertions(+), 2 deletions(-)

diff --git a/drivers/net/dsa/sja1105/sja1105_main.c b/drivers/net/dsa/sja1105/sja1105_main.c
index 93d1f607eeab..028ed1ebe358 100644
--- a/drivers/net/dsa/sja1105/sja1105_main.c
+++ b/drivers/net/dsa/sja1105/sja1105_main.c
@@ -260,6 +260,13 @@ static int sja1105_init_static_vlan(struct sja1105_private *priv)
table = &priv->static_config.tables[BLK_IDX_VLAN_LOOKUP];

/* The static VLAN table will only contain the initial pvid of 0.
+ * All other VLANs are to be configured through dynamic entries,
+ * and kept in the static configuration table as backing memory.
+ * The pvid of 0 is sufficient to pass traffic while the ports are
+ * standalone and when vlan_filtering is disabled. When filtering
+ * gets enabled, the switchdev core sets up the VLAN ID 1 and sets
+ * it as the new pvid. Actually 'pvid 1' still comes up in 'bridge
+ * vlan' even when vlan_filtering is off, but it has no effect.
*/
if (table->entry_count) {
kfree(table->entries);
@@ -400,8 +407,11 @@ static int sja1105_init_general_params(struct sja1105_private *priv)
.vlmask = 0,
/* Only update correctionField for 1-step PTP (L2 transport) */
.ignore2stf = 0,
- .tpid = ETH_P_8021Q,
- .tpid2 = ETH_P_8021Q,
+ /* Forcefully disable VLAN filtering by telling
+ * the switch that VLAN has a different EtherType.
+ */
+ .tpid = ETH_P_EDSA,
+ .tpid2 = ETH_P_EDSA,
/* P/Q/R/S only */
.queue_ts = 0,
.egrmirrvid = 0,
@@ -930,12 +940,245 @@ static void sja1105_bridge_leave(struct dsa_switch *ds, int port,
sja1105_bridge_member(ds, port, br, false);
}

+/* For situations where we need to change a setting at runtime that is only
+ * available through the static configuration, resetting the switch in order
+ * to upload the new static config is unavoidable. Back up the settings we
+ * modify at runtime (currently only MAC) and restore them after uploading,
+ * such that this operation is relatively seamless.
+ */
+static int sja1105_static_config_reload(struct sja1105_private *priv)
+{
+ struct sja1105_mac_config_entry *mac;
+ int speed_mbps[SJA1105_NUM_PORTS];
+ int rc, i;
+
+ mac = priv->static_config.tables[BLK_IDX_MAC_CONFIG].entries;
+
+ /* Back up settings changed by sja1105_adjust_port_config and
+ * and restore their defaults.
+ */
+ for (i = 0; i < SJA1105_NUM_PORTS; i++) {
+ speed_mbps[i] = sja1105_speed[mac[i].speed];
+ mac[i].speed = SJA1105_SPEED_AUTO;
+ }
+
+ /* Reset switch and send updated static configuration */
+ rc = sja1105_static_config_upload(priv);
+ if (rc < 0)
+ goto out;
+
+ /* Configure the CGU (PLLs) for MII and RMII PHYs.
+ * For these interfaces there is no dynamic configuration
+ * needed, since PLLs have same settings at all speeds.
+ */
+ rc = sja1105_clocking_setup(priv);
+ if (rc < 0)
+ goto out;
+
+ for (i = 0; i < SJA1105_NUM_PORTS; i++) {
+ bool enabled = (speed_mbps[i] != 0);
+
+ rc = sja1105_adjust_port_config(priv, i, speed_mbps[i],
+ enabled);
+ if (rc < 0)
+ goto out;
+ }
+out:
+ return rc;
+}
+
+#define sja1105_vlan_filtering_enabled(priv) \
+ (((struct sja1105_general_params_entry *) \
+ ((struct sja1105_private *)priv)->static_config. \
+ tables[BLK_IDX_GENERAL_PARAMS].entries)->tpid == ETH_P_8021Q)
+
+/* The TPID setting belongs to the General Parameters table,
+ * which can only be partially reconfigured at runtime (and not the TPID).
+ * So a switch reset is required.
+ */
+static int sja1105_change_tpid(struct sja1105_private *priv,
+ u16 tpid, u16 tpid2)
+{
+ struct sja1105_general_params_entry *general_params;
+ struct sja1105_table *table;
+
+ table = &priv->static_config.tables[BLK_IDX_GENERAL_PARAMS];
+ general_params = table->entries;
+ general_params->tpid = tpid;
+ general_params->tpid2 = tpid2;
+ return sja1105_static_config_reload(priv);
+}
+
+static int sja1105_pvid_apply(struct sja1105_private *priv, int port, u16 pvid)
+{
+ struct sja1105_mac_config_entry *mac;
+
+ mac = priv->static_config.tables[BLK_IDX_MAC_CONFIG].entries;
+
+ mac[port].vlanid = pvid;
+
+ return sja1105_dynamic_config_write(priv, BLK_IDX_MAC_CONFIG, port,
+ &mac[port], true);
+}
+
+static int sja1105_is_vlan_configured(struct sja1105_private *priv, u16 vid)
+{
+ struct sja1105_vlan_lookup_entry *vlan;
+ int count, i;
+
+ vlan = priv->static_config.tables[BLK_IDX_VLAN_LOOKUP].entries;
+ count = priv->static_config.tables[BLK_IDX_VLAN_LOOKUP].entry_count;
+
+ for (i = 0; i < count; i++)
+ if (vlan[i].vlanid == vid)
+ return i;
+
+ /* Return an invalid entry index if not found */
+ return -1;
+}
+
+static int sja1105_vlan_apply(struct sja1105_private *priv, int port, u16 vid,
+ bool enabled, bool untagged)
+{
+ struct sja1105_vlan_lookup_entry *vlan;
+ struct sja1105_table *table;
+ bool keep = true;
+ int match, rc;
+
+ table = &priv->static_config.tables[BLK_IDX_VLAN_LOOKUP];
+
+ match = sja1105_is_vlan_configured(priv, vid);
+ if (match < 0) {
+ /* Can't delete a missing entry. */
+ if (!enabled)
+ return 0;
+ rc = sja1105_table_resize(table, table->entry_count + 1);
+ if (rc)
+ return rc;
+ match = table->entry_count - 1;
+ }
+ /* Assign pointer after the resize (it's new memory) */
+ vlan = table->entries;
+ vlan[match].vlanid = vid;
+ if (enabled) {
+ vlan[match].vlan_bc |= BIT(port);
+ vlan[match].vmemb_port |= BIT(port);
+ } else {
+ vlan[match].vlan_bc &= ~BIT(port);
+ vlan[match].vmemb_port &= ~BIT(port);
+ }
+ /* Also unset tag_port if removing this VLAN was requested,
+ * just so we don't have a confusing bitmap (no practical purpose).
+ */
+ if (untagged || !enabled)
+ vlan[match].tag_port &= ~BIT(port);
+ else
+ vlan[match].tag_port |= BIT(port);
+ /* If there's no port left as member of this VLAN,
+ * it's time for it to go.
+ */
+ if (!vlan[match].vmemb_port)
+ keep = false;
+
+ dev_dbg(priv->ds->dev,
+ "%s: port %d, vid %llu, broadcast domain 0x%llx, "
+ "port members 0x%llx, tagged ports 0x%llx, keep %d\n",
+ __func__, port, vlan[match].vlanid, vlan[match].vlan_bc,
+ vlan[match].vmemb_port, vlan[match].tag_port, keep);
+
+ rc = sja1105_dynamic_config_write(priv, BLK_IDX_VLAN_LOOKUP, vid,
+ &vlan[match], keep);
+ if (rc < 0)
+ return rc;
+
+ if (!keep)
+ return sja1105_table_delete_entry(table, match);
+
+ return 0;
+}
+
static enum dsa_tag_protocol
sja1105_get_tag_protocol(struct dsa_switch *ds, int port)
{
return DSA_TAG_PROTO_NONE;
}

+/* This callback needs to be present */
+static int sja1105_vlan_prepare(struct dsa_switch *ds, int port,
+ const struct switchdev_obj_port_vlan *vlan)
+{
+ return 0;
+}
+
+static int sja1105_vlan_filtering(struct dsa_switch *ds, int port, bool enabled)
+{
+ struct sja1105_private *priv = ds->priv;
+ int rc;
+
+ if (enabled && !sja1105_vlan_filtering_enabled(priv))
+ /* Enable VLAN filtering.
+ * TODO read these from bridge_dev->protocol.
+ */
+ rc = sja1105_change_tpid(priv, ETH_P_8021Q, ETH_P_8021AD);
+ else if (!enabled && sja1105_vlan_filtering_enabled(priv))
+ /* Disable VLAN filtering. TODO: Install a TPID
+ * that also encodes the switch ID (aka ds->index)
+ * so that stacking switch tags will be supported.
+ */
+ rc = sja1105_change_tpid(priv, ETH_P_EDSA, ETH_P_EDSA);
+ else
+ return 0;
+ if (rc)
+ dev_err(ds->dev, "Failed to change VLAN Ethertype\n");
+
+ return rc;
+}
+
+static void sja1105_vlan_add(struct dsa_switch *ds, int port,
+ const struct switchdev_obj_port_vlan *vlan)
+{
+ struct sja1105_private *priv = ds->priv;
+ u16 vid;
+ int rc;
+
+ for (vid = vlan->vid_begin; vid <= vlan->vid_end; vid++) {
+ rc = sja1105_vlan_apply(priv, port, vid, true, vlan->flags &
+ BRIDGE_VLAN_INFO_UNTAGGED);
+ if (rc < 0) {
+ dev_err(ds->dev, "Failed to add VLAN %d to port %d: %d\n",
+ vid, port, rc);
+ return;
+ }
+ if (vlan->flags & BRIDGE_VLAN_INFO_PVID) {
+ rc = sja1105_pvid_apply(ds->priv, port, vid);
+ if (rc < 0) {
+ dev_err(ds->dev, "Failed to set pvid %d on port %d: %d\n",
+ vid, port, rc);
+ return;
+ }
+ }
+ }
+}
+
+static int sja1105_vlan_del(struct dsa_switch *ds, int port,
+ const struct switchdev_obj_port_vlan *vlan)
+{
+ struct sja1105_private *priv = ds->priv;
+ u16 vid;
+ int rc;
+
+ for (vid = vlan->vid_begin; vid <= vlan->vid_end; vid++) {
+ rc = sja1105_vlan_apply(priv, port, vid, false, vlan->flags &
+ BRIDGE_VLAN_INFO_UNTAGGED);
+ if (rc < 0) {
+ dev_err(ds->dev, "Failed to remove VLAN %d from port %d: %d\n",
+ vid, port, rc);
+ return rc;
+ }
+ }
+ return 0;
+}
+
/* The programming model for the SJA1105 switch is "all-at-once" via static
* configuration tables. Some of these can be dynamically modified at runtime,
* but not the xMII mode parameters table.
@@ -971,6 +1214,15 @@ static int sja1105_setup(struct dsa_switch *ds)
dev_err(ds->dev, "Failed to configure MII clocking: %d\n", rc);
return rc;
}
+ /* On SJA1105, VLAN filtering per se is always enabled in hardware.
+ * The only thing we can do to disable it is lie about what the 802.1Q
+ * EtherType is. So it will still try to apply VLAN filtering, but all
+ * ingress traffic (except frames received with EtherType of
+ * ETH_P_EDSA, which are invalid) will be internally tagged with a
+ * distorted VLAN header where the TPID is ETH_P_EDSA, and the VLAN ID
+ * is the port pvid.
+ */
+ ds->vlan_filtering_is_global = true;

return 0;
}
@@ -984,6 +1236,10 @@ static const struct dsa_switch_ops sja1105_switch_ops = {
.port_fdb_del = sja1105_fdb_del,
.port_bridge_join = sja1105_bridge_join,
.port_bridge_leave = sja1105_bridge_leave,
+ .port_vlan_prepare = sja1105_vlan_prepare,
+ .port_vlan_filtering = sja1105_vlan_filtering,
+ .port_vlan_add = sja1105_vlan_add,
+ .port_vlan_del = sja1105_vlan_del,
.port_mdb_prepare = sja1105_mdb_prepare,
.port_mdb_add = sja1105_mdb_add,
.port_mdb_del = sja1105_mdb_del,
diff --git a/drivers/net/dsa/sja1105/sja1105_static_config.c b/drivers/net/dsa/sja1105/sja1105_static_config.c
index f5d1866216bd..c477f0520141 100644
--- a/drivers/net/dsa/sja1105/sja1105_static_config.c
+++ b/drivers/net/dsa/sja1105/sja1105_static_config.c
@@ -1034,3 +1034,41 @@ void sja1105_static_config_free(struct sja1105_static_config *config)
}
}

+int sja1105_table_delete_entry(struct sja1105_table *table, int i)
+{
+ size_t entry_size = table->ops->unpacked_entry_size;
+ u8 *entries = table->entries;
+
+ if (i > table->entry_count)
+ return -ERANGE;
+
+ memmove(entries + i * entry_size, entries + (i + 1) * entry_size,
+ (table->entry_count - i) * entry_size);
+
+ table->entry_count--;
+
+ return 0;
+}
+
+/* No pointers to table->entries should be kept when this is called. */
+int sja1105_table_resize(struct sja1105_table *table, size_t new_count)
+{
+ size_t entry_size = table->ops->unpacked_entry_size;
+ void *new_entries, *old_entries = table->entries;
+
+ if (new_count > table->ops->max_entry_count)
+ return -ERANGE;
+
+ new_entries = kcalloc(new_count, entry_size, GFP_KERNEL);
+ if (!new_entries)
+ return -ENOMEM;
+
+ memcpy(new_entries, old_entries, min(new_count, table->entry_count) *
+ entry_size);
+
+ table->entries = new_entries;
+ table->entry_count = new_count;
+ kfree(old_entries);
+ return 0;
+}
+
diff --git a/drivers/net/dsa/sja1105/sja1105_static_config.h b/drivers/net/dsa/sja1105/sja1105_static_config.h
index 1c331c9e20b3..2f9db15a454d 100644
--- a/drivers/net/dsa/sja1105/sja1105_static_config.h
+++ b/drivers/net/dsa/sja1105/sja1105_static_config.h
@@ -297,6 +297,9 @@ int sja1105_static_config_init(struct sja1105_static_config *config,
u64 device_id, u64 part_nr);
void sja1105_static_config_free(struct sja1105_static_config *config);

+int sja1105_table_delete_entry(struct sja1105_table *table, int i);
+int sja1105_table_resize(struct sja1105_table *table, size_t new_count);
+
u32 sja1105_crc32(const void *buf, size_t len);

void sja1105_pack(void *buf, const u64 *val, int start, int end, size_t len);
--
2.17.1