[PATCH v5 net-next 15/15] net: dsa: mv88e6xxx: MST Offloading

Tobias Waldekranz
2022-03-16T15:10:48Z

Allocate a SID in the STU for each MSTID in use by a bridge and handle
the mapping of MSTIDs to VLANs using the SID field of each VTU entry.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
---
drivers/net/dsa/mv88e6xxx/chip.c | 250 ++++++++++++++++++++++++++++++-
drivers/net/dsa/mv88e6xxx/chip.h | 13 ++
2 files changed, 255 insertions(+), 8 deletions(-)

diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index c14a62aa6a6c..bed1a5658eac 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -1667,24 +1667,31 @@ static int mv88e6xxx_pvt_setup(struct mv88e6xxx_chip *chip)
return 0;
}

-static void mv88e6xxx_port_fast_age(struct dsa_switch *ds, int port)
+static int mv88e6xxx_port_fast_age_fid(struct mv88e6xxx_chip *chip, int port,
+ u16 fid)
{
- struct mv88e6xxx_chip *chip = ds->priv;
- int err;
-
- if (dsa_to_port(ds, port)->lag)
+ if (dsa_to_port(chip->ds, port)->lag)
/* Hardware is incapable of fast-aging a LAG through a
* regular ATU move operation. Until we have something
* more fancy in place this is a no-op.
*/
- return;
+ return -EOPNOTSUPP;
+
+ return mv88e6xxx_g1_atu_remove(chip, fid, port, false);
+}
+
+static void mv88e6xxx_port_fast_age(struct dsa_switch *ds, int port)
+{
+ struct mv88e6xxx_chip *chip = ds->priv;
+ int err;

mv88e6xxx_reg_lock(chip);
- err = mv88e6xxx_g1_atu_remove(chip, 0, port, false);
+ err = mv88e6xxx_port_fast_age_fid(chip, port, 0);
mv88e6xxx_reg_unlock(chip);

if (err)
- dev_err(ds->dev, "p%d: failed to flush ATU\n", port);
+ dev_err(chip->ds->dev, "p%d: failed to flush ATU: %d\n",
+ port, err);
}

static int mv88e6xxx_vtu_setup(struct mv88e6xxx_chip *chip)
@@ -1818,6 +1825,160 @@ static int mv88e6xxx_stu_setup(struct mv88e6xxx_chip *chip)
return mv88e6xxx_stu_loadpurge(chip, &stu);
}

+static int mv88e6xxx_sid_get(struct mv88e6xxx_chip *chip, u8 *sid)
+{
+ DECLARE_BITMAP(busy, MV88E6XXX_N_SID) = { 0 };
+ struct mv88e6xxx_mst *mst;
+
+ __set_bit(0, busy);
+
+ list_for_each_entry(mst, &chip->msts, node)
+ __set_bit(mst->stu.sid, busy);
+
+ *sid = find_first_zero_bit(busy, MV88E6XXX_N_SID);
+
+ return (*sid >= mv88e6xxx_max_sid(chip)) ? -ENOSPC : 0;
+}
+
+static int mv88e6xxx_mst_put(struct mv88e6xxx_chip *chip, u8 sid)
+{
+ struct mv88e6xxx_mst *mst, *tmp;
+ int err;
+
+ if (!sid)
+ return 0;
+
+ list_for_each_entry_safe(mst, tmp, &chip->msts, node) {
+ if (mst->stu.sid != sid)
+ continue;
+
+ if (!refcount_dec_and_test(&mst->refcnt))
+ return 0;
+
+ mst->stu.valid = false;
+ err = mv88e6xxx_stu_loadpurge(chip, &mst->stu);
+ if (err) {
+ refcount_set(&mst->refcnt, 1);
+ return err;
+ }
+
+ list_del(&mst->node);
+ kfree(mst);
+ return 0;
+ }
+
+ return -ENOENT;
+}
+
+static int mv88e6xxx_mst_get(struct mv88e6xxx_chip *chip, struct net_device *br,
+ u16 msti, u8 *sid)
+{
+ struct mv88e6xxx_mst *mst;
+ int err, i;
+
+ if (!mv88e6xxx_has_stu(chip)) {
+ err = -EOPNOTSUPP;
+ goto err;
+ }
+
+ if (!msti) {
+ *sid = 0;
+ return 0;
+ }
+
+ list_for_each_entry(mst, &chip->msts, node) {
+ if (mst->br == br && mst->msti == msti) {
+ refcount_inc(&mst->refcnt);
+ *sid = mst->stu.sid;
+ return 0;
+ }
+ }
+
+ err = mv88e6xxx_sid_get(chip, sid);
+ if (err)
+ goto err;
+
+ mst = kzalloc(sizeof(*mst), GFP_KERNEL);
+ if (!mst) {
+ err = -ENOMEM;
+ goto err;
+ }
+
+ INIT_LIST_HEAD(&mst->node);
+ refcount_set(&mst->refcnt, 1);
+ mst->br = br;
+ mst->msti = msti;
+ mst->stu.valid = true;
+ mst->stu.sid = *sid;
+
+ /* The bridge starts out all ports in the disabled state. But
+ * a STU state of disabled means to go by the port-global
+ * state. So we set all user port's initial state to blocking,
+ * to match the bridge's behavior.
+ */
+ for (i = 0; i < mv88e6xxx_num_ports(chip); i++)
+ mst->stu.state[i] = dsa_is_user_port(chip->ds, i) ?
+ MV88E6XXX_PORT_CTL0_STATE_BLOCKING :
+ MV88E6XXX_PORT_CTL0_STATE_DISABLED;
+
+ err = mv88e6xxx_stu_loadpurge(chip, &mst->stu);
+ if (err)
+ goto err_free;
+
+ list_add_tail(&mst->node, &chip->msts);
+ return 0;
+
+err_free:
+ kfree(mst);
+err:
+ return err;
+}
+
+static int mv88e6xxx_port_mst_state_set(struct dsa_switch *ds, int port,
+ const struct switchdev_mst_state *st)
+{
+ struct dsa_port *dp = dsa_to_port(ds, port);
+ struct mv88e6xxx_chip *chip = ds->priv;
+ struct mv88e6xxx_mst *mst;
+ u8 state;
+ int err;
+
+ if (!mv88e6xxx_has_stu(chip))
+ return -EOPNOTSUPP;
+
+ switch (st->state) {
+ case BR_STATE_DISABLED:
+ case BR_STATE_BLOCKING:
+ case BR_STATE_LISTENING:
+ state = MV88E6XXX_PORT_CTL0_STATE_BLOCKING;
+ break;
+ case BR_STATE_LEARNING:
+ state = MV88E6XXX_PORT_CTL0_STATE_LEARNING;
+ break;
+ case BR_STATE_FORWARDING:
+ state = MV88E6XXX_PORT_CTL0_STATE_FORWARDING;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ list_for_each_entry(mst, &chip->msts, node) {
+ if (mst->br == dsa_port_bridge_dev_get(dp) &&
+ mst->msti == st->msti) {
+ if (mst->stu.state[port] == state)
+ return 0;
+
+ mst->stu.state[port] = state;
+ mv88e6xxx_reg_lock(chip);
+ err = mv88e6xxx_stu_loadpurge(chip, &mst->stu);
+ mv88e6xxx_reg_unlock(chip);
+ return err;
+ }
+ }
+
+ return -ENOENT;
+}
+
static int mv88e6xxx_port_check_hw_vlan(struct dsa_switch *ds, int port,
u16 vid)
{
@@ -2437,6 +2598,12 @@ static int mv88e6xxx_port_vlan_leave(struct mv88e6xxx_chip *chip,
if (err)
return err;

+ if (!vlan.valid) {
+ err = mv88e6xxx_mst_put(chip, vlan.sid);
+ if (err)
+ return err;
+ }
+
return mv88e6xxx_g1_atu_remove(chip, vlan.fid, port, false);
}

@@ -2482,6 +2649,69 @@ static int mv88e6xxx_port_vlan_del(struct dsa_switch *ds, int port,
return err;
}

+static int mv88e6xxx_port_vlan_fast_age(struct dsa_switch *ds, int port, u16 vid)
+{
+ struct mv88e6xxx_chip *chip = ds->priv;
+ struct mv88e6xxx_vtu_entry vlan;
+ int err;
+
+ mv88e6xxx_reg_lock(chip);
+
+ err = mv88e6xxx_vtu_get(chip, vid, &vlan);
+ if (err)
+ goto unlock;
+
+ err = mv88e6xxx_port_fast_age_fid(chip, port, vlan.fid);
+
+unlock:
+ mv88e6xxx_reg_unlock(chip);
+
+ return err;
+}
+
+static int mv88e6xxx_vlan_msti_set(struct dsa_switch *ds,
+ struct dsa_bridge bridge,
+ const struct switchdev_vlan_msti *msti)
+{
+ struct mv88e6xxx_chip *chip = ds->priv;
+ struct mv88e6xxx_vtu_entry vlan;
+ u8 old_sid, new_sid;
+ int err;
+
+ mv88e6xxx_reg_lock(chip);
+
+ err = mv88e6xxx_vtu_get(chip, msti->vid, &vlan);
+ if (err)
+ goto unlock;
+
+ if (!vlan.valid) {
+ err = -EINVAL;
+ goto unlock;
+ }
+
+ old_sid = vlan.sid;
+
+ err = mv88e6xxx_mst_get(chip, bridge.dev, msti->msti, &new_sid);
+ if (err)
+ goto unlock;
+
+ if (new_sid != old_sid) {
+ vlan.sid = new_sid;
+
+ err = mv88e6xxx_vtu_loadpurge(chip, &vlan);
+ if (err) {
+ mv88e6xxx_mst_put(chip, new_sid);
+ goto unlock;
+ }
+ }
+
+ err = mv88e6xxx_mst_put(chip, old_sid);
+
+unlock:
+ mv88e6xxx_reg_unlock(chip);
+ return err;
+}
+
static int mv88e6xxx_port_fdb_add(struct dsa_switch *ds, int port,
const unsigned char *addr, u16 vid,
struct dsa_db db)
@@ -6008,6 +6238,7 @@ static struct mv88e6xxx_chip *mv88e6xxx_alloc_chip(struct device *dev)
mutex_init(&chip->reg_lock);
INIT_LIST_HEAD(&chip->mdios);
idr_init(&chip->policies);
+ INIT_LIST_HEAD(&chip->msts);

return chip;
}
@@ -6540,10 +6771,13 @@ static const struct dsa_switch_ops mv88e6xxx_switch_ops = {
.port_pre_bridge_flags = mv88e6xxx_port_pre_bridge_flags,
.port_bridge_flags = mv88e6xxx_port_bridge_flags,
.port_stp_state_set = mv88e6xxx_port_stp_state_set,
+ .port_mst_state_set = mv88e6xxx_port_mst_state_set,
.port_fast_age = mv88e6xxx_port_fast_age,
+ .port_vlan_fast_age = mv88e6xxx_port_vlan_fast_age,
.port_vlan_filtering = mv88e6xxx_port_vlan_filtering,
.port_vlan_add = mv88e6xxx_port_vlan_add,
.port_vlan_del = mv88e6xxx_port_vlan_del,
+ .vlan_msti_set = mv88e6xxx_vlan_msti_set,
.port_fdb_add = mv88e6xxx_port_fdb_add,
.port_fdb_del = mv88e6xxx_port_fdb_del,
.port_fdb_dump = mv88e6xxx_port_fdb_dump,
diff --git a/drivers/net/dsa/mv88e6xxx/chip.h b/drivers/net/dsa/mv88e6xxx/chip.h
index 6d4daa24d3e5..6a0b66354e1d 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.h
+++ b/drivers/net/dsa/mv88e6xxx/chip.h
@@ -297,6 +297,16 @@ struct mv88e6xxx_region_priv {
enum mv88e6xxx_region_id id;
};

+struct mv88e6xxx_mst {
+ struct list_head node;
+
+ refcount_t refcnt;
+ struct net_device *br;
+ u16 msti;
+
+ struct mv88e6xxx_stu_entry stu;
+};
+
struct mv88e6xxx_chip {
const struct mv88e6xxx_info *info;

@@ -397,6 +407,9 @@ struct mv88e6xxx_chip {

/* devlink regions */
struct devlink_region *regions[_MV88E6XXX_REGION_MAX];
+
+ /* Bridge MST to SID mappings */
+ struct list_head msts;
};

struct mv88e6xxx_bus_ops {
--
2.25.1