net: dsa: introduce dsa_towards_port helper

Add a new helper returning the local port used to reach an arbitrary
switch port in the fabric.

Its only user at the moment is the dsa_upstream_port helper, which
returns the local port reaching the dedicated CPU port, but it will be
used in cross-chip FDB operations.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Vivien Didelot 2017-11-30 12:56:42 -05:00 committed by David S. Miller
parent 5420683ae3
commit 3b8fac5d90
1 changed files with 13 additions and 10 deletions

View File

@ -296,20 +296,23 @@ static inline u32 dsa_user_ports(struct dsa_switch *ds)
return mask;
}
/* Return the local port used to reach an arbitrary switch port */
static inline unsigned int dsa_towards_port(struct dsa_switch *ds, int device,
int port)
{
if (device == ds->index)
return port;
else
return ds->rtable[device];
}
/* Return the local port used to reach the dedicated CPU port */
static inline u8 dsa_upstream_port(struct dsa_switch *ds)
{
struct dsa_switch_tree *dst = ds->dst;
struct dsa_port *cpu_dp = dst->cpu_dp;
/*
* If this is the root switch (i.e. the switch that connects
* to the CPU), return the cpu port number on this switch.
* Else return the (DSA) port number that connects to the
* switch that is one hop closer to the cpu.
*/
if (dst->cpu_dp->ds == ds)
return dst->cpu_dp->index;
else
return ds->rtable[dst->cpu_dp->ds->index];
return dsa_towards_port(ds, cpu_dp->ds->index, cpu_dp->index);
}
typedef int dsa_fdb_dump_cb_t(const unsigned char *addr, u16 vid,