net: dsa: sja1105: add broadcast and per-traffic class policers

This patch adds complete support for manipulating the L2 Policing Tables
from this switch. There are 45 table entries, one entry per each port
and traffic class, and one dedicated entry for broadcast traffic for
each ingress port.

Policing entries are shareable, and we use this functionality to support
shared block filters.

We are modeling broadcast policers as simple tc-flower matches on
dst_mac. As for the traffic class policers, the switch only deduces the
traffic class from the VLAN PCP field, so it makes sense to model this
as a tc-flower match on vlan_prio.

How to limit broadcast traffic coming from all front-panel ports to a
cumulated total of 10 Mbit/s:

tc qdisc add dev sw0p0 ingress_block 1 clsact
tc qdisc add dev sw0p1 ingress_block 1 clsact
tc qdisc add dev sw0p2 ingress_block 1 clsact
tc qdisc add dev sw0p3 ingress_block 1 clsact
tc filter add block 1 flower skip_sw dst_mac ff:ff:ff:ff:ff:ff \
	action police rate 10mbit burst 64k

How to limit traffic with VLAN PCP 0 (also includes untagged traffic) to
100 Mbit/s on port 0 only:

tc filter add dev sw0p0 ingress protocol 802.1Q flower skip_sw \
	vlan_prio 0 action police rate 100mbit burst 64k

The broadcast, VLAN PCP and port policers are compatible with one
another (can be installed at the same time on a port).

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/sja1105/Makefile

@@ -4,6 +4,7 @@ obj-$(CONFIG_NET_DSA_SJA1105) += sja1105.o
 sja1105-objs := \
     sja1105_spi.o \
     sja1105_main.o \
+    sja1105_flower.o \
     sja1105_ethtool.o \
     sja1105_clocking.o \
     sja1105_static_config.o \

drivers/net/dsa/sja1105/sja1105.h

@@ -19,6 +19,7 @@
  * The passed parameter is in multiples of 1 ms.
  */
 #define SJA1105_AGEING_TIME_MS(ms)	((ms) / 10)
+#define SJA1105_NUM_L2_POLICERS		45
 
 typedef enum {
 	SPI_READ = 0,
@@ -95,6 +96,36 @@ struct sja1105_info {
 	const char *name;
 };
 
+enum sja1105_rule_type {
+	SJA1105_RULE_BCAST_POLICER,
+	SJA1105_RULE_TC_POLICER,
+};
+
+struct sja1105_rule {
+	struct list_head list;
+	unsigned long cookie;
+	unsigned long port_mask;
+	enum sja1105_rule_type type;
+
+	union {
+		/* SJA1105_RULE_BCAST_POLICER */
+		struct {
+			int sharindx;
+		} bcast_pol;
+
+		/* SJA1105_RULE_TC_POLICER */
+		struct {
+			int sharindx;
+			int tc;
+		} tc_pol;
+	};
+};
+
+struct sja1105_flow_block {
+	struct list_head rules;
+	bool l2_policer_used[SJA1105_NUM_L2_POLICERS];
+};
+
 struct sja1105_private {
 	struct sja1105_static_config static_config;
 	bool rgmii_rx_delay[SJA1105_NUM_PORTS];
@@ -103,6 +134,7 @@ struct sja1105_private {
 	struct gpio_desc *reset_gpio;
 	struct spi_device *spidev;
 	struct dsa_switch *ds;
+	struct sja1105_flow_block flow_block;
 	struct sja1105_port ports[SJA1105_NUM_PORTS];
 	/* Serializes transmission of management frames so that
 	 * the switch doesn't confuse them with one another.
@@ -222,4 +254,12 @@ size_t sja1105pqrs_mac_config_entry_packing(void *buf, void *entry_ptr,
 size_t sja1105pqrs_avb_params_entry_packing(void *buf, void *entry_ptr,
 					    enum packing_op op);
 
+/* From sja1105_flower.c */
+int sja1105_cls_flower_del(struct dsa_switch *ds, int port,
+			   struct flow_cls_offload *cls, bool ingress);
+int sja1105_cls_flower_add(struct dsa_switch *ds, int port,
+			   struct flow_cls_offload *cls, bool ingress);
+void sja1105_flower_setup(struct dsa_switch *ds);
+void sja1105_flower_teardown(struct dsa_switch *ds);
+
 #endif