Merge branch 'knobs-for-npc-default-rule-counters'

Linu Cherian says:

====================
Knobs for NPC default rule counters

Patch 1 introduce _rvu_mcam_remove/add_counter_from/to_rule
by refactoring existing code

Patch 2 adds a devlink param to enable/disable counters for default
rules. Once enabled, counters can

Patch 3 adds documentation for devlink params

v4: https://lore.kernel.org/20241029035739.1981839-1-lcherian@marvell.com
====================

Link: https://patch.msgid.link/20241105125620.2114301-1-lcherian@marvell.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Documentation/networking/devlink/octeontx2.rst

@@ -40,6 +40,27 @@ The ``octeontx2 AF`` driver implements the following driver-specific parameters.
      - runtime
      - Use to set the quantum which hardware uses for scheduling among transmit queues.
        Hardware uses weighted DWRR algorithm to schedule among all transmit queues.
+   * - ``npc_mcam_high_zone_percent``
+     - u8
+     - runtime
+     - Use to set the number of high priority zone entries in NPC MCAM that can be allocated
+       by a user, out of the three priority zone categories high, mid and low.
+   * - ``npc_def_rule_cntr``
+     - bool
+     - runtime
+     - Use to enable or disable hit counters for the default rules in NPC MCAM.
+       Its not guaranteed that counters gets enabled and mapped to all the default rules,
+       since the counters are scarce and driver follows a best effort approach.
+       The default rule serves as the primary packet steering rule for a specific PF or VF,
+       based on its DMAC address which is installed by AF driver as part of its initialization.
+       Sample command to read hit counters for default rule from debugfs is as follows,
+       cat /sys/kernel/debug/cn10k/npc/mcam_rules
+   * - ``nix_maxlf``
+     - u16
+     - runtime
+     - Use to set the maximum number of LFs in NIX hardware block. This would be useful
+       to increase the availability of default resources allocated to enabled LFs like
+       MCAM entries for example.
 
 The ``octeontx2 PF`` driver implements the following driver-specific parameters.
 

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

@@ -525,6 +525,7 @@ struct rvu {
 	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 */
@@ -960,7 +961,11 @@ void rvu_npc_disable_default_entries(struct rvu *rvu, u16 pcifunc, int nixlf);
 void rvu_npc_enable_default_entries(struct rvu *rvu, u16 pcifunc, int nixlf);
 void rvu_npc_update_flowkey_alg_idx(struct rvu *rvu, u16 pcifunc, int nixlf,
 				    int group, int alg_idx, int mcam_index);
-
+void __rvu_mcam_remove_counter_from_rule(struct rvu *rvu, u16 pcifunc,
+					 struct rvu_npc_mcam_rule *rule);
+void __rvu_mcam_add_counter_to_rule(struct rvu *rvu, u16 pcifunc,
+				    struct rvu_npc_mcam_rule *rule,
+				    struct npc_install_flow_rsp *rsp);
 void rvu_npc_get_mcam_entry_alloc_info(struct rvu *rvu, u16 pcifunc,
 				       int blkaddr, int *alloc_cnt,
 				       int *enable_cnt);
@@ -985,6 +990,7 @@ void npc_set_mcam_action(struct rvu *rvu, struct npc_mcam *mcam,
 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

@@ -1238,6 +1238,7 @@ enum rvu_af_dl_param_id {
 	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,
 };
 
@@ -1358,6 +1359,32 @@ static int rvu_af_dl_npc_mcam_high_zone_percent_validate(struct devlink *devlink
 	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)
 {
@@ -1444,6 +1471,11 @@ static const struct devlink_param rvu_af_dl_params[] = {
 			     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

@@ -2691,6 +2691,49 @@ void npc_mcam_rsrcs_reserve(struct rvu *rvu, int blkaddr, int entry_idx)
 	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)
@@ -2975,9 +3018,9 @@ int rvu_mbox_handler_npc_mcam_shift_entry(struct rvu *rvu,
 	return rc;
 }
 
-int rvu_mbox_handler_npc_mcam_alloc_counter(struct rvu *rvu,
-			struct npc_mcam_alloc_counter_req *req,
-			struct npc_mcam_alloc_counter_rsp *rsp)
+static int __npc_mcam_alloc_counter(struct rvu *rvu,
+				    struct npc_mcam_alloc_counter_req *req,
+				    struct npc_mcam_alloc_counter_rsp *rsp)
 {
 	struct npc_mcam *mcam = &rvu->hw->mcam;
 	u16 pcifunc = req->hdr.pcifunc;
@@ -2998,11 +3041,9 @@ int rvu_mbox_handler_npc_mcam_alloc_counter(struct rvu *rvu,
 	if (!req->contig && req->count > NPC_MAX_NONCONTIG_COUNTERS)
 		return NPC_MCAM_INVALID_REQ;
 
-	mutex_lock(&mcam->lock);
 
 	/* Check if unused counters are available or not */
 	if (!rvu_rsrc_free_count(&mcam->counters)) {
-		mutex_unlock(&mcam->lock);
 		return NPC_MCAM_ALLOC_FAILED;
 	}
 
@@ -3035,12 +3076,27 @@ int rvu_mbox_handler_npc_mcam_alloc_counter(struct rvu *rvu,
 		}
 	}
 
-	mutex_unlock(&mcam->lock);
 	return 0;
 }
 
-int rvu_mbox_handler_npc_mcam_free_counter(struct rvu *rvu,
-		struct npc_mcam_oper_counter_req *req, struct msg_rsp *rsp)
+int rvu_mbox_handler_npc_mcam_alloc_counter(struct rvu *rvu,
+			struct npc_mcam_alloc_counter_req *req,
+			struct npc_mcam_alloc_counter_rsp *rsp)
+{
+	struct npc_mcam *mcam = &rvu->hw->mcam;
+	int err;
+
+	mutex_lock(&mcam->lock);
+
+	err = __npc_mcam_alloc_counter(rvu, req, rsp);
+
+	mutex_unlock(&mcam->lock);
+	return err;
+}
+
+static int __npc_mcam_free_counter(struct rvu *rvu,
+				   struct npc_mcam_oper_counter_req *req,
+				   struct msg_rsp *rsp)
 {
 	struct npc_mcam *mcam = &rvu->hw->mcam;
 	u16 index, entry = 0;
@@ -3050,10 +3106,8 @@ int rvu_mbox_handler_npc_mcam_free_counter(struct rvu *rvu,
 	if (blkaddr < 0)
 		return NPC_MCAM_INVALID_REQ;
 
-	mutex_lock(&mcam->lock);
 	err = npc_mcam_verify_counter(mcam, req->hdr.pcifunc, req->cntr);
 	if (err) {
-		mutex_unlock(&mcam->lock);
 		return err;
 	}
 
@@ -3077,10 +3131,66 @@ int rvu_mbox_handler_npc_mcam_free_counter(struct rvu *rvu,
 					      index, req->cntr);
 	}
 
-	mutex_unlock(&mcam->lock);
 	return 0;
 }
 
+int rvu_mbox_handler_npc_mcam_free_counter(struct rvu *rvu,
+		struct npc_mcam_oper_counter_req *req, struct msg_rsp *rsp)
+{
+	struct npc_mcam *mcam = &rvu->hw->mcam;
+	int err;
+
+	mutex_lock(&mcam->lock);
+
+	err = __npc_mcam_free_counter(rvu, req, rsp);
+
+	mutex_unlock(&mcam->lock);
+
+	return err;
+}
+
+void __rvu_mcam_remove_counter_from_rule(struct rvu *rvu, u16 pcifunc,
+					 struct rvu_npc_mcam_rule *rule)
+{
+	struct npc_mcam_oper_counter_req free_req = { 0 };
+	struct msg_rsp free_rsp;
+
+	if (!rule->has_cntr)
+		return;
+
+	free_req.hdr.pcifunc = pcifunc;
+	free_req.cntr = rule->cntr;
+
+	__npc_mcam_free_counter(rvu, &free_req, &free_rsp);
+	rule->has_cntr = false;
+}
+
+void __rvu_mcam_add_counter_to_rule(struct rvu *rvu, u16 pcifunc,
+				    struct rvu_npc_mcam_rule *rule,
+				    struct npc_install_flow_rsp *rsp)
+{
+	struct npc_mcam_alloc_counter_req cntr_req = { 0 };
+	struct npc_mcam_alloc_counter_rsp cntr_rsp = { 0 };
+	int err;
+
+	cntr_req.hdr.pcifunc = pcifunc;
+	cntr_req.contig = true;
+	cntr_req.count = 1;
+
+	/* we try to allocate a counter to track the stats of this
+	 * rule. If counter could not be allocated then proceed
+	 * without counter because counters are limited than entries.
+	 */
+	err = __npc_mcam_alloc_counter(rvu, &cntr_req, &cntr_rsp);
+	if (!err && cntr_rsp.count) {
+		rule->cntr = cntr_rsp.cntr;
+		rule->has_cntr = true;
+		rsp->counter = rule->cntr;
+	} else {
+		rsp->counter = err;
+	}
+}
+
 int rvu_mbox_handler_npc_mcam_unmap_counter(struct rvu *rvu,
 		struct npc_mcam_unmap_counter_req *req, struct msg_rsp *rsp)
 {

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

@@ -1081,44 +1081,26 @@ static void rvu_mcam_add_rule(struct npc_mcam *mcam,
 static void rvu_mcam_remove_counter_from_rule(struct rvu *rvu, u16 pcifunc,
 					      struct rvu_npc_mcam_rule *rule)
 {
-	struct npc_mcam_oper_counter_req free_req = { 0 };
-	struct msg_rsp free_rsp;
+	struct npc_mcam *mcam = &rvu->hw->mcam;
 
-	if (!rule->has_cntr)
-		return;
+	mutex_lock(&mcam->lock);
 
-	free_req.hdr.pcifunc = pcifunc;
-	free_req.cntr = rule->cntr;
+	__rvu_mcam_remove_counter_from_rule(rvu, pcifunc, rule);
 
-	rvu_mbox_handler_npc_mcam_free_counter(rvu, &free_req, &free_rsp);
-	rule->has_cntr = false;
+	mutex_unlock(&mcam->lock);
 }
 
 static void rvu_mcam_add_counter_to_rule(struct rvu *rvu, u16 pcifunc,
 					 struct rvu_npc_mcam_rule *rule,
 					 struct npc_install_flow_rsp *rsp)
 {
-	struct npc_mcam_alloc_counter_req cntr_req = { 0 };
-	struct npc_mcam_alloc_counter_rsp cntr_rsp = { 0 };
-	int err;
+	struct npc_mcam *mcam = &rvu->hw->mcam;
 
-	cntr_req.hdr.pcifunc = pcifunc;
-	cntr_req.contig = true;
-	cntr_req.count = 1;
+	mutex_lock(&mcam->lock);
 
-	/* we try to allocate a counter to track the stats of this
-	 * rule. If counter could not be allocated then proceed
-	 * without counter because counters are limited than entries.
-	 */
-	err = rvu_mbox_handler_npc_mcam_alloc_counter(rvu, &cntr_req,
-						      &cntr_rsp);
-	if (!err && cntr_rsp.count) {
-		rule->cntr = cntr_rsp.cntr;
-		rule->has_cntr = true;
-		rsp->counter = rule->cntr;
-	} else {
-		rsp->counter = err;
-	}
+	__rvu_mcam_add_counter_to_rule(rvu, pcifunc, rule, rsp);
+
+	mutex_unlock(&mcam->lock);
 }
 
 static int npc_mcast_update_action_index(struct rvu *rvu, struct npc_install_flow_req *req,