Commit 291d1e72 authored by Vladimir Oltean's avatar Vladimir Oltean Committed by David S. Miller

net: dsa: sja1105: Add support for FDB and MDB management

Currently only the (more difficult) first generation E/T series is
supported. Here the TCAM is only 4-way associative, and to know where
the hardware will search for a FDB entry, we need to perform the same
hash algorithm in order to install the entry in the correct bin.

On P/Q/R/S, the TCAM should be fully associative. However the SPI
command interface is different, and because I don't have access to a
new-generation device at the moment, support for it is TODO.
Signed-off-by: default avatarVladimir Oltean <olteanv@gmail.com>
Reviewed-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 8aa9ebcc
......@@ -123,6 +123,8 @@ int sja1105_dynamic_config_write(struct sja1105_private *priv,
enum sja1105_blk_idx blk_idx,
int index, void *entry, bool keep);
u8 sja1105_fdb_hash(struct sja1105_private *priv, const u8 *addr, u16 vid);
/* Common implementations for the static and dynamic configs */
size_t sja1105_l2_forwarding_entry_packing(void *buf, void *entry_ptr,
enum packing_op op);
......
......@@ -487,3 +487,46 @@ int sja1105_dynamic_config_write(struct sja1105_private *priv,
return 0;
}
static u8 sja1105_crc8_add(u8 crc, u8 byte, u8 poly)
{
int i;
for (i = 0; i < 8; i++) {
if ((crc ^ byte) & (1 << 7)) {
crc <<= 1;
crc ^= poly;
} else {
crc <<= 1;
}
byte <<= 1;
}
return crc;
}
/* CRC8 algorithm with non-reversed input, non-reversed output,
* no input xor and no output xor. Code customized for receiving
* the SJA1105 E/T FDB keys (vlanid, macaddr) as input. CRC polynomial
* is also received as argument in the Koopman notation that the switch
* hardware stores it in.
*/
u8 sja1105_fdb_hash(struct sja1105_private *priv, const u8 *addr, u16 vid)
{
struct sja1105_l2_lookup_params_entry *l2_lookup_params =
priv->static_config.tables[BLK_IDX_L2_LOOKUP_PARAMS].entries;
u64 poly_koopman = l2_lookup_params->poly;
/* Convert polynomial from Koopman to 'normal' notation */
u8 poly = (u8)(1 + (poly_koopman << 1));
u64 vlanid = l2_lookup_params->shared_learn ? 0 : vid;
u64 input = (vlanid << 48) | ether_addr_to_u64(addr);
u8 crc = 0; /* seed */
int i;
/* Mask the eight bytes starting from MSB one at a time */
for (i = 56; i >= 0; i -= 8) {
u8 byte = (input & (0xffull << i)) >> i;
crc = sja1105_crc8_add(crc, byte, poly);
}
return crc;
}
......@@ -179,6 +179,9 @@ static int sja1105_init_static_fdb(struct sja1105_private *priv)
table = &priv->static_config.tables[BLK_IDX_L2_LOOKUP];
/* We only populate the FDB table through dynamic
* L2 Address Lookup entries
*/
if (table->entry_count) {
kfree(table->entries);
table->entry_count = 0;
......@@ -689,6 +692,191 @@ static void sja1105_adjust_link(struct dsa_switch *ds, int port,
sja1105_adjust_port_config(priv, port, phydev->speed, true);
}
/* First-generation switches have a 4-way set associative TCAM that
* holds the FDB entries. An FDB index spans from 0 to 1023 and is comprised of
* a "bin" (grouping of 4 entries) and a "way" (an entry within a bin).
* For the placement of a newly learnt FDB entry, the switch selects the bin
* based on a hash function, and the way within that bin incrementally.
*/
static inline int sja1105et_fdb_index(int bin, int way)
{
return bin * SJA1105ET_FDB_BIN_SIZE + way;
}
static int sja1105_is_fdb_entry_in_bin(struct sja1105_private *priv, int bin,
const u8 *addr, u16 vid,
struct sja1105_l2_lookup_entry *match,
int *last_unused)
{
int way;
for (way = 0; way < SJA1105ET_FDB_BIN_SIZE; way++) {
struct sja1105_l2_lookup_entry l2_lookup = {0};
int index = sja1105et_fdb_index(bin, way);
/* Skip unused entries, optionally marking them
* into the return value
*/
if (sja1105_dynamic_config_read(priv, BLK_IDX_L2_LOOKUP,
index, &l2_lookup)) {
if (last_unused)
*last_unused = way;
continue;
}
if (l2_lookup.macaddr == ether_addr_to_u64(addr) &&
l2_lookup.vlanid == vid) {
if (match)
*match = l2_lookup;
return way;
}
}
/* Return an invalid entry index if not found */
return -1;
}
static int sja1105_fdb_add(struct dsa_switch *ds, int port,
const unsigned char *addr, u16 vid)
{
struct sja1105_l2_lookup_entry l2_lookup = {0};
struct sja1105_private *priv = ds->priv;
struct device *dev = ds->dev;
int last_unused = -1;
int bin, way;
bin = sja1105_fdb_hash(priv, addr, vid);
way = sja1105_is_fdb_entry_in_bin(priv, bin, addr, vid,
&l2_lookup, &last_unused);
if (way >= 0) {
/* We have an FDB entry. Is our port in the destination
* mask? If yes, we need to do nothing. If not, we need
* to rewrite the entry by adding this port to it.
*/
if (l2_lookup.destports & BIT(port))
return 0;
l2_lookup.destports |= BIT(port);
} else {
int index = sja1105et_fdb_index(bin, way);
/* We don't have an FDB entry. We construct a new one and
* try to find a place for it within the FDB table.
*/
l2_lookup.macaddr = ether_addr_to_u64(addr);
l2_lookup.destports = BIT(port);
l2_lookup.vlanid = vid;
if (last_unused >= 0) {
way = last_unused;
} else {
/* Bin is full, need to evict somebody.
* Choose victim at random. If you get these messages
* often, you may need to consider changing the
* distribution function:
* static_config[BLK_IDX_L2_LOOKUP_PARAMS].entries->poly
*/
get_random_bytes(&way, sizeof(u8));
way %= SJA1105ET_FDB_BIN_SIZE;
dev_warn(dev, "Warning, FDB bin %d full while adding entry for %pM. Evicting entry %u.\n",
bin, addr, way);
/* Evict entry */
sja1105_dynamic_config_write(priv, BLK_IDX_L2_LOOKUP,
index, NULL, false);
}
}
l2_lookup.index = sja1105et_fdb_index(bin, way);
return sja1105_dynamic_config_write(priv, BLK_IDX_L2_LOOKUP,
l2_lookup.index, &l2_lookup,
true);
}
static int sja1105_fdb_del(struct dsa_switch *ds, int port,
const unsigned char *addr, u16 vid)
{
struct sja1105_l2_lookup_entry l2_lookup = {0};
struct sja1105_private *priv = ds->priv;
int index, bin, way;
bool keep;
bin = sja1105_fdb_hash(priv, addr, vid);
way = sja1105_is_fdb_entry_in_bin(priv, bin, addr, vid,
&l2_lookup, NULL);
if (way < 0)
return 0;
index = sja1105et_fdb_index(bin, way);
/* We have an FDB entry. Is our port in the destination mask? If yes,
* we need to remove it. If the resulting port mask becomes empty, we
* need to completely evict the FDB entry.
* Otherwise we just write it back.
*/
if (l2_lookup.destports & BIT(port))
l2_lookup.destports &= ~BIT(port);
if (l2_lookup.destports)
keep = true;
else
keep = false;
return sja1105_dynamic_config_write(priv, BLK_IDX_L2_LOOKUP,
index, &l2_lookup, keep);
}
static int sja1105_fdb_dump(struct dsa_switch *ds, int port,
dsa_fdb_dump_cb_t *cb, void *data)
{
struct sja1105_private *priv = ds->priv;
struct device *dev = ds->dev;
int i;
for (i = 0; i < SJA1105_MAX_L2_LOOKUP_COUNT; i++) {
struct sja1105_l2_lookup_entry l2_lookup = {0};
u8 macaddr[ETH_ALEN];
int rc;
rc = sja1105_dynamic_config_read(priv, BLK_IDX_L2_LOOKUP,
i, &l2_lookup);
/* No fdb entry at i, not an issue */
if (rc == -EINVAL)
continue;
if (rc) {
dev_err(dev, "Failed to dump FDB: %d\n", rc);
return rc;
}
/* FDB dump callback is per port. This means we have to
* disregard a valid entry if it's not for this port, even if
* only to revisit it later. This is inefficient because the
* 1024-sized FDB table needs to be traversed 4 times through
* SPI during a 'bridge fdb show' command.
*/
if (!(l2_lookup.destports & BIT(port)))
continue;
u64_to_ether_addr(l2_lookup.macaddr, macaddr);
cb(macaddr, l2_lookup.vlanid, false, data);
}
return 0;
}
/* This callback needs to be present */
static int sja1105_mdb_prepare(struct dsa_switch *ds, int port,
const struct switchdev_obj_port_mdb *mdb)
{
return 0;
}
static void sja1105_mdb_add(struct dsa_switch *ds, int port,
const struct switchdev_obj_port_mdb *mdb)
{
sja1105_fdb_add(ds, port, mdb->addr, mdb->vid);
}
static int sja1105_mdb_del(struct dsa_switch *ds, int port,
const struct switchdev_obj_port_mdb *mdb)
{
return sja1105_fdb_del(ds, port, mdb->addr, mdb->vid);
}
static int sja1105_bridge_member(struct dsa_switch *ds, int port,
struct net_device *br, bool member)
{
......@@ -791,8 +979,14 @@ static const struct dsa_switch_ops sja1105_switch_ops = {
.get_tag_protocol = sja1105_get_tag_protocol,
.setup = sja1105_setup,
.adjust_link = sja1105_adjust_link,
.port_fdb_dump = sja1105_fdb_dump,
.port_fdb_add = sja1105_fdb_add,
.port_fdb_del = sja1105_fdb_del,
.port_bridge_join = sja1105_bridge_join,
.port_bridge_leave = sja1105_bridge_leave,
.port_mdb_prepare = sja1105_mdb_prepare,
.port_mdb_add = sja1105_mdb_add,
.port_mdb_del = sja1105_mdb_del,
};
static int sja1105_check_device_id(struct sja1105_private *priv)
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment