Commit c279c726 authored by Vladimir Oltean's avatar Vladimir Oltean Committed by David S. Miller
Browse files

net: dsa: sja1105: implement the port MTU callbacks 



On this switch, the frame length enforcements are performed by the
ingress policers. There are 2 types of those: regular L2 (also called
best-effort) and Virtual Link policers (an ARINC664/AFDX concept for
defining L2 streams with certain QoS abilities). To avoid future
confusion, I prefer to call the reset reason "Best-effort policers",
even though the VL policers are not yet supported.

We also need to change the setup of the initial static config, such that
DSA calls to .change_mtu (which are expensive) become no-ops and don't
reset the switch 5 times.

A driver-level decision is to unconditionally allow single VLAN-tagged
traffic on all ports. The CPU port must accept an additional VLAN header
for the DSA tag, which is again a driver-level decision.

The policers actually count bytes not only from the SDU, but also from
the Ethernet header and FCS, so those need to be accounted for as well.

Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 6ae5834b

drivers/net/dsa/sja1105/sja1105.h

+1 −0
Original line number Diff line number Diff line
@@ -126,6 +126,7 @@ enum sja1105_reset_reason { 
	SJA1105_RX_HWTSTAMPING,

	SJA1105_AGEING_TIME,

	SJA1105_SCHEDULING,

	SJA1105_BEST_EFFORT_POLICING,

};



int sja1105_static_config_reload(struct sja1105_private *priv,

drivers/net/dsa/sja1105/sja1105_main.c

+46 −4
Original line number Diff line number Diff line
@@ -519,12 +519,12 @@ static int sja1105_init_avb_params(struct sja1105_private *priv) 
#define SJA1105_RATE_MBPS(speed) (((speed) * 64000) / 1000)



static void sja1105_setup_policer(struct sja1105_l2_policing_entry *policing,

				  int index)

				  int index, int mtu)

{

	policing[index].sharindx = index;

	policing[index].smax = 65535; /* Burst size in bytes */

	policing[index].rate = SJA1105_RATE_MBPS(1000);

	policing[index].maxlen = ETH_FRAME_LEN + VLAN_HLEN + ETH_FCS_LEN;

	policing[index].maxlen = mtu;

	policing[index].partition = 0;

}
@@ -556,12 +556,16 @@ static int sja1105_init_l2_policing(struct sja1105_private *priv) 
	 */

	for (i = 0, k = 0; i < SJA1105_NUM_PORTS; i++) {

		int bcast = (SJA1105_NUM_PORTS * SJA1105_NUM_TC) + i;

		int mtu = VLAN_ETH_FRAME_LEN + ETH_FCS_LEN;



		if (dsa_is_cpu_port(priv->ds, i))

			mtu += VLAN_HLEN;



		for (j = 0; j < SJA1105_NUM_TC; j++, k++)

			sja1105_setup_policer(policing, k);

			sja1105_setup_policer(policing, k, mtu);



		/* Set up this port's policer for broadcast traffic */

		sja1105_setup_policer(policing, bcast);

		sja1105_setup_policer(policing, bcast, mtu);

	}

	return 0;

}
@@ -1544,6 +1548,7 @@ static const char * const sja1105_reset_reasons[] = { 
	[SJA1105_RX_HWTSTAMPING] = "RX timestamping",

	[SJA1105_AGEING_TIME] = "Ageing time",

	[SJA1105_SCHEDULING] = "Time-aware scheduling",

	[SJA1105_BEST_EFFORT_POLICING] = "Best-effort policing",

};



/* For situations where we need to change a setting at runtime that is only
@@ -1952,6 +1957,8 @@ static int sja1105_setup(struct dsa_switch *ds) 
	/* Advertise the 8 egress queues */

	ds->num_tx_queues = SJA1105_NUM_TC;



	ds->mtu_enforcement_ingress = true;



	/* The DSA/switchdev model brings up switch ports in standalone mode by

	 * default, and that means vlan_filtering is 0 since they're not under

	 * a bridge, so it's safe to set up switch tagging at this time.
@@ -2120,6 +2127,39 @@ static int sja1105_set_ageing_time(struct dsa_switch *ds, 
	return sja1105_static_config_reload(priv, SJA1105_AGEING_TIME);

}



static int sja1105_change_mtu(struct dsa_switch *ds, int port, int new_mtu)

{

	int bcast = (SJA1105_NUM_PORTS * SJA1105_NUM_TC) + port;

	struct sja1105_l2_policing_entry *policing;

	struct sja1105_private *priv = ds->priv;

	int tc;



	new_mtu += VLAN_ETH_HLEN + ETH_FCS_LEN;



	if (dsa_is_cpu_port(ds, port))

		new_mtu += VLAN_HLEN;



	policing = priv->static_config.tables[BLK_IDX_L2_POLICING].entries;



	/* We set all 9 port policers to the same value, so just checking the

	 * broadcast one is fine.

	 */

	if (policing[bcast].maxlen == new_mtu)

		return 0;



	for (tc = 0; tc < SJA1105_NUM_TC; tc++)

		policing[port * SJA1105_NUM_TC + tc].maxlen = new_mtu;



	policing[bcast].maxlen = new_mtu;



	return sja1105_static_config_reload(priv, SJA1105_BEST_EFFORT_POLICING);

}



static int sja1105_get_max_mtu(struct dsa_switch *ds, int port)

{

	return 2043 - VLAN_ETH_HLEN - ETH_FCS_LEN;

}



static int sja1105_port_setup_tc(struct dsa_switch *ds, int port,

				 enum tc_setup_type type,

				 void *type_data)
@@ -2215,6 +2255,8 @@ static const struct dsa_switch_ops sja1105_switch_ops = { 
	.setup			= sja1105_setup,

	.teardown		= sja1105_teardown,

	.set_ageing_time	= sja1105_set_ageing_time,

	.port_change_mtu	= sja1105_change_mtu,

	.port_max_mtu		= sja1105_get_max_mtu,

	.phylink_validate	= sja1105_phylink_validate,

	.phylink_mac_link_state	= sja1105_mac_pcs_get_state,

	.phylink_mac_config	= sja1105_mac_config,

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