net: mvpp2: cls: Use RSS contexts to handle RSS tables

The PPv2 controller has 8 RSS tables that are shared across all ports on
a given PPv2 instance. The previous implementation allocated one table
per port, leaving others unused.

By using RSS contexts, we can make use of multiple RSS tables per
port, one being the default table (always id 0), the other ones being
used as destinations for flow steering, in the same way as rx rings.

This commit introduces RSS contexts management in the PPv2 driver. We
always reserve one table per port, allocated when the port is probed.

The global table list is stored in the struct mvpp2, as it's a global
resource. Each port then maintains a list of indices in that global
table, that way each port can have it's own numbering scheme starting
from 0.

One limitation that seems unavoidable is that the hashing parameters are
shared across all RSS contexts for a given port. Hashing parameters for
ctx 0 will be applied to all contexts.

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

1 files changed, 13 insertions, 3 deletions

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
index bb466af9434b..18ae8d06b692 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
@@ -626,6 +626,7 @@
 #define MVPP2_N_RFS_RULES		(MVPP2_N_RFS_ENTRIES_PER_FLOW * 7)
 
 /* RSS constants */
+#define MVPP22_N_RSS_TABLES		8
 #define MVPP22_RSS_TABLE_ENTRIES	32
 
 /* IPv6 max L3 address size */
@@ -727,6 +728,10 @@ enum mvpp2_prs_l3_cast {
 /* Definitions */
 struct mvpp2_dbgfs_entries;
 
+struct mvpp2_rss_table {
+	u32 indir[MVPP22_RSS_TABLE_ENTRIES];
+};
+
 /* Shared Packet Processor resources */
 struct mvpp2 {
 	/* Shared registers' base addresses */
@@ -790,6 +795,9 @@ struct mvpp2 {
 
 	/* Debugfs entries private data */
 	struct mvpp2_dbgfs_entries *dbgfs_entries;
+
+	/* RSS Indirection tables */
+	struct mvpp2_rss_table *rss_tables[MVPP22_N_RSS_TABLES];
 };
 
 struct mvpp2_pcpu_stats {
@@ -921,12 +929,14 @@ struct mvpp2_port {
 
 	u32 tx_time_coal;
 
-	/* RSS indirection table */
-	u32 indir[MVPP22_RSS_TABLE_ENTRIES];
-
 	/* List of steering rules active on that port */
 	struct mvpp2_ethtool_fs *rfs_rules[MVPP2_N_RFS_ENTRIES_PER_FLOW];
 	int n_rfs_rules;
+
+	/* Each port has its own view of the rss contexts, so that it can number
+	 * them from 0
+	 */
+	int rss_ctx[MVPP22_N_RSS_TABLES];
 };
 
 /* The mvpp2_tx_desc and mvpp2_rx_desc structures describe the