octeontx2-af: Knobs for NPC default rule counters

Add devlink knobs to enable/disable counters on NPC
default rule entries.

Sample command to enable default rule counters:
devlink dev param set <dev> name npc_def_rule_cntr value true cmode runtime

Sample command to read the counter:
cat /sys/kernel/debug/cn10k/npc/mcam_rules

Signed-off-by: Linu Cherian <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

drivers/net/ethernet/marvell/octeontx2/af/rvu.h

···
 	struct mutex		alias_lock; /* Serialize bar2 alias access */
 	int			vfs; /* Number of VFs attached to RVU */
 	u16			vf_devid; /* VF devices id */
+	bool			def_rule_cntr_en;
 	int			nix_blkaddr[MAX_NIX_BLKS];
 
 	/* Mbox */
···
 void npc_read_mcam_entry(struct rvu *rvu, struct npc_mcam *mcam,
 			 int blkaddr, u16 src, struct mcam_entry *entry,
 			 u8 *intf, u8 *ena);
+int npc_config_cntr_default_entries(struct rvu *rvu, bool enable);
 bool is_cgx_config_permitted(struct rvu *rvu, u16 pcifunc);
 bool is_mac_feature_supported(struct rvu *rvu, int pf, int feature);
 u32  rvu_cgx_get_fifolen(struct rvu *rvu);

drivers/net/ethernet/marvell/octeontx2/af/rvu_devlink.c

···
 	RVU_AF_DEVLINK_PARAM_ID_DWRR_MTU,
 	RVU_AF_DEVLINK_PARAM_ID_NPC_MCAM_ZONE_PERCENT,
 	RVU_AF_DEVLINK_PARAM_ID_NPC_EXACT_FEATURE_DISABLE,
+	RVU_AF_DEVLINK_PARAM_ID_NPC_DEF_RULE_CNTR_ENABLE,
 	RVU_AF_DEVLINK_PARAM_ID_NIX_MAXLF,
 };
 
···
 	return 0;
 }
 
+static int rvu_af_dl_npc_def_rule_cntr_get(struct devlink *devlink, u32 id,
+					   struct devlink_param_gset_ctx *ctx)
+{
+	struct rvu_devlink *rvu_dl = devlink_priv(devlink);
+	struct rvu *rvu = rvu_dl->rvu;
+
+	ctx->val.vbool = rvu->def_rule_cntr_en;
+
+	return 0;
+}
+
+static int rvu_af_dl_npc_def_rule_cntr_set(struct devlink *devlink, u32 id,
+					   struct devlink_param_gset_ctx *ctx,
+					   struct netlink_ext_ack *extack)
+{
+	struct rvu_devlink *rvu_dl = devlink_priv(devlink);
+	struct rvu *rvu = rvu_dl->rvu;
+	int err;
+
+	err = npc_config_cntr_default_entries(rvu, ctx->val.vbool);
+	if (!err)
+		rvu->def_rule_cntr_en = ctx->val.vbool;
+
+	return err;
+}
+
 static int rvu_af_dl_nix_maxlf_get(struct devlink *devlink, u32 id,
 				   struct devlink_param_gset_ctx *ctx)
 {
···
 			     rvu_af_dl_npc_mcam_high_zone_percent_get,
 			     rvu_af_dl_npc_mcam_high_zone_percent_set,
 			     rvu_af_dl_npc_mcam_high_zone_percent_validate),
+	DEVLINK_PARAM_DRIVER(RVU_AF_DEVLINK_PARAM_ID_NPC_DEF_RULE_CNTR_ENABLE,
+			     "npc_def_rule_cntr", DEVLINK_PARAM_TYPE_BOOL,
+			     BIT(DEVLINK_PARAM_CMODE_RUNTIME),
+			     rvu_af_dl_npc_def_rule_cntr_get,
+			     rvu_af_dl_npc_def_rule_cntr_set, NULL),
 	DEVLINK_PARAM_DRIVER(RVU_AF_DEVLINK_PARAM_ID_NIX_MAXLF,
 			     "nix_maxlf", DEVLINK_PARAM_TYPE_U16,
 			     BIT(DEVLINK_PARAM_CMODE_RUNTIME),

drivers/net/ethernet/marvell/octeontx2/af/rvu_npc.c

···
 	npc_mcam_set_bit(mcam, entry_idx);
 }
 
+int npc_config_cntr_default_entries(struct rvu *rvu, bool enable)
+{
+	struct npc_mcam *mcam = &rvu->hw->mcam;
+	struct npc_install_flow_rsp rsp;
+	struct rvu_npc_mcam_rule *rule;
+	int blkaddr;
+
+	blkaddr = rvu_get_blkaddr(rvu, BLKTYPE_NPC, 0);
+	if (blkaddr < 0)
+		return -EINVAL;
+
+	mutex_lock(&mcam->lock);
+	list_for_each_entry(rule, &mcam->mcam_rules, list) {
+		if (!is_mcam_entry_enabled(rvu, mcam, blkaddr, rule->entry))
+			continue;
+		if (!rule->default_rule)
+			continue;
+		if (enable && !rule->has_cntr) { /* Alloc and map new counter */
+			__rvu_mcam_add_counter_to_rule(rvu, rule->owner,
+						       rule, &rsp);
+			if (rsp.counter < 0) {
+				dev_err(rvu->dev,
+					"%s: Failed to allocate cntr for default rule (err=%d)\n",
+					__func__, rsp.counter);
+				break;
+			}
+			npc_map_mcam_entry_and_cntr(rvu, mcam, blkaddr,
+						    rule->entry, rsp.counter);
+			/* Reset counter before use */
+			rvu_write64(rvu, blkaddr,
+				    NPC_AF_MATCH_STATX(rule->cntr), 0x0);
+		}
+
+		/* Free and unmap counter */
+		if (!enable && rule->has_cntr)
+			__rvu_mcam_remove_counter_from_rule(rvu, rule->owner,
+							    rule);
+	}
+	mutex_unlock(&mcam->lock);
+
+	return 0;
+}
+
 int rvu_mbox_handler_npc_mcam_alloc_entry(struct rvu *rvu,
 					  struct npc_mcam_alloc_entry_req *req,
 					  struct npc_mcam_alloc_entry_rsp *rsp)