net: mvpp2: add an RSS classification step for each flow

One of the classification action that can be performed is to compute a
hash of the packet header based on some header fields, and lookup a RSS
table based on this hash to determine the final RxQ.

This is done by adding one lookup entry per flow per port, so that we
can configure the hash generation parameters for each flow and each
port.

There are 2 possible engines that can be used for RSS hash generation :

 - C3HA, that generates a hash based on up to 4 header-extracted fields
 - C3HB, that does the same as c3HA, but also includes L4 info in the hash

There are a lot of fields that can be extracted from the header. For now,
we only use the ones that we can configure using ethtool :
 - DST MAC address
 - L3 info
 - Source IP
 - Destination IP
 - Source port
 - Destination port

The C3HB engine is selected when we use L4 fields (src/dst port).

               Header parser          Dec table
 Ingress pkt  +-------------+ flow id +----------------------------+
------------->| TCAM + SRAM |-------->|TCP IPv4 w/ VLAN, not frag  |
              +-------------+         |TCP IPv4 w/o VLAN, not frag |
                                      |TCP IPv4 w/ VLAN, frag      |--+
                                      |etc.                        |  |
                                      +----------------------------+  |
                                                                      |
                                            Flow table                |
  +---------+   +------------+         +--------------------------+   |
  | RSS tbl |<--| Classifier |<--------| flow 0: C2 lookup        |   |
  +---------+   +------------+         |         C3 lookup port 0 |   |
                 |         |           |         C3 lookup port 1 |   |
         +-----------+ +-------------+ |         ...              |   |
         | C2 engine | | C3H engines | | flow 1: C2 lookup        |<--+
         +-----------+ +-------------+ |         C3 lookup port 0 |
                                       |         ...              |
                                       | ...                      |
                                       | flow 51 : C2 lookup      |
                                       |           ...            |
                                       +--------------------------+

The C2 engine also gains the role of enabling and disabling the RSS
table lookup for this packet.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 15 insertions, 0 deletions

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_cls.h b/drivers/net/ethernet/marvell/mvpp2/mvpp2_cls.h
index 747c5f055b82..21bd0249be0d 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_cls.h
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_cls.h
@@ -62,6 +62,18 @@ enum mvpp2_cls_engine {
 #define MVPP22_CLS_HEK_IP6_5T	(MVPP22_CLS_HEK_IP6_2T | \
 				 MVPP22_CLS_HEK_L4_OPTS)
 
+enum mvpp2_cls_field_id {
+	MVPP22_CLS_FIELD_MAC_DA = 0x03,
+	MVPP22_CLS_FIELD_VLAN = 0x06,
+	MVPP22_CLS_FIELD_L3_PROTO = 0x0f,
+	MVPP22_CLS_FIELD_IP4SA = 0x10,
+	MVPP22_CLS_FIELD_IP4DA = 0x11,
+	MVPP22_CLS_FIELD_IP6SA = 0x17,
+	MVPP22_CLS_FIELD_IP6DA = 0x1a,
+	MVPP22_CLS_FIELD_L4SIP = 0x1d,
+	MVPP22_CLS_FIELD_L4DIP = 0x1e,
+};
+
 enum mvpp2_cls_flow_seq {
 	MVPP2_CLS_FLOW_SEQ_NORMAL = 0,
 	MVPP2_CLS_FLOW_SEQ_FIRST1,
@@ -188,6 +200,9 @@ void mvpp22_rss_fill_table(struct mvpp2_port *port, u32 table);
 
 void mvpp22_rss_port_init(struct mvpp2_port *port);
 
+void mvpp22_rss_enable(struct mvpp2_port *port);
+void mvpp22_rss_disable(struct mvpp2_port *port);
+
 void mvpp2_cls_init(struct mvpp2 *priv);
 
 void mvpp2_cls_port_config(struct mvpp2_port *port);