Re: [PATCH net-next 5/5] net: dsa: mv88e6xxx: implementation of dynamic ATU entries

[Simon Horman <simon.horman@corigine.com>]

On Mon, Jan 30, 2023 at 06:34:29PM +0100, Hans J. Schultz wrote:
> For 802.1X or MAB security authed hosts we want to have these hosts authed
> by adding dynamic FDB entries, so that if an authed host goes silent for
> a time period it's FDB entry will be removed and it must reauth when
> wanting to communicate again.
> In the mv88e6xxx offloaded case, we can use the HoldAt1 feature, that
> gives an age out interrupt when the FDB entry is about to age out, so
> that userspace can be notified of the entry being deleted with the help
> of an SWITCHDEV_FDB_DEL_TO_BRIDGE event.
> When adding a dynamic entry the bridge must be informed that the driver
> takes care of the ageing be sending an SWITCHDEV_FDB_OFFLOADED event,
> telling the bridge that this added FDB entry will be handled by the
> driver.
> With this implementation, trace events for age out interrupts are also
> added.
> 
> note: A special case arises with the age out interrupt, as the entry
> state/spid (source port id) value read from the registers will be zero.
> Thus we need to extract the source port from the port vector instead.
> 
> Signed-off-by: Hans J. Schultz <netdev@kapio-technology.com>
> ---
>  drivers/net/dsa/mv88e6xxx/chip.c        | 18 ++++++--
>  drivers/net/dsa/mv88e6xxx/global1_atu.c | 21 +++++++++
>  drivers/net/dsa/mv88e6xxx/port.c        |  6 ++-
>  drivers/net/dsa/mv88e6xxx/switchdev.c   | 61 +++++++++++++++++++++++++
>  drivers/net/dsa/mv88e6xxx/switchdev.h   |  5 ++
>  drivers/net/dsa/mv88e6xxx/trace.h       |  5 ++
>  6 files changed, 110 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
> index 61d5dc4680e3..a0007d96b2a3 100644
> --- a/drivers/net/dsa/mv88e6xxx/chip.c
> +++ b/drivers/net/dsa/mv88e6xxx/chip.c
> @@ -42,6 +42,7 @@
>  #include "ptp.h"
>  #include "serdes.h"
>  #include "smi.h"
> +#include "switchdev.h"
>  
>  static void assert_reg_lock(struct mv88e6xxx_chip *chip)
>  {
> @@ -2726,18 +2727,25 @@ static int mv88e6xxx_port_fdb_add(struct dsa_switch *ds, int port,
>  				  const unsigned char *addr, u16 vid,
>  				  u16 fdb_flags, struct dsa_db db)
>  {
> +	bool is_dynamic = !!(fdb_flags & DSA_FDB_FLAG_DYNAMIC);
>  	struct mv88e6xxx_chip *chip = ds->priv;
> +	u8 state;
>  	int err;
>  
> -	/* Ignore entries with flags set */
> -	if (fdb_flags)
> -		return 0;
> +	state = MV88E6XXX_G1_ATU_DATA_STATE_UC_STATIC;
> +	if (is_dynamic)
> +		state = MV88E6XXX_G1_ATU_DATA_STATE_UC_AGE_7_NEWEST;

What if flags other than DSA_FDB_FLAG_DYNAMIC are set (in future)?

> +	else
> +		if (fdb_flags)

nit: else if (fdb_flags)

> +			return 0;
>  

...