octeontx2-af: Add new devlink param to configure maximum usable NIX block LFs

On some silicon variants the number of available CAM entries are
less. Reserving one entry for each NIX-LF for default DMAC based pkt
forwarding rules will reduce the number of available CAM entries
further. Hence add configurability via devlink to set maximum number of
NIX-LFs needed which inturn frees up some CAM entries.

Signed-off-by: Suman Ghosh <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

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

···
 			       u64 bcast_mcast_val, u64 bcast_mcast_mask);
 void npc_mcam_rsrcs_reserve(struct rvu *rvu, int blkaddr, int entry_idx);
 bool npc_is_feature_supported(struct rvu *rvu, u64 features, u8 intf);
+int npc_mcam_rsrcs_init(struct rvu *rvu, int blkaddr);
+void npc_mcam_rsrcs_deinit(struct rvu *rvu);
 
 /* CPT APIs */
 int rvu_cpt_register_interrupts(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_EXACT_FEATURE_DISABLE,
 	RVU_AF_DEVLINK_PARAM_ID_NPC_MCAM_ZONE_PERCENT,
+	RVU_AF_DEVLINK_PARAM_ID_NIX_MAXLF,
 };
 
 static int rvu_af_npc_exact_feature_get(struct devlink *devlink, u32 id,
···
 	return 0;
 }
 
+static int rvu_af_dl_nix_maxlf_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.vu16 = (u16)rvu_get_nixlf_count(rvu);
+
+	return 0;
+}
+
+static int rvu_af_dl_nix_maxlf_set(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;
+	struct rvu_block *block;
+	int blkaddr = 0;
+
+	npc_mcam_rsrcs_deinit(rvu);
+	blkaddr = rvu_get_next_nix_blkaddr(rvu, blkaddr);
+	while (blkaddr) {
+		block = &rvu->hw->block[blkaddr];
+		block->lf.max = ctx->val.vu16;
+		blkaddr = rvu_get_next_nix_blkaddr(rvu, blkaddr);
+	}
+
+	blkaddr = rvu_get_blkaddr(rvu, BLKTYPE_NPC, 0);
+	npc_mcam_rsrcs_init(rvu, blkaddr);
+
+	return 0;
+}
+
+static int rvu_af_dl_nix_maxlf_validate(struct devlink *devlink, u32 id,
+					union devlink_param_value val,
+					struct netlink_ext_ack *extack)
+{
+	struct rvu_devlink *rvu_dl = devlink_priv(devlink);
+	struct rvu *rvu = rvu_dl->rvu;
+	u16 max_nix0_lf, max_nix1_lf;
+	struct npc_mcam *mcam;
+	u64 cfg;
+
+	cfg = rvu_read64(rvu, BLKADDR_NIX0, NIX_AF_CONST2);
+	max_nix0_lf = cfg & 0xFFF;
+	cfg = rvu_read64(rvu, BLKADDR_NIX1, NIX_AF_CONST2);
+	max_nix1_lf = cfg & 0xFFF;
+
+	/* Do not allow user to modify maximum NIX LFs while mcam entries
+	 * have already been assigned.
+	 */
+	mcam = &rvu->hw->mcam;
+	if (mcam->bmap_fcnt < mcam->bmap_entries) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "mcam entries have already been assigned, can't resize");
+		return -EPERM;
+	}
+
+	if (max_nix0_lf && val.vu16 > max_nix0_lf) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "requested nixlf is greater than the max supported nix0_lf");
+		return -EPERM;
+	}
+
+	if (max_nix1_lf && val.vu16 > max_nix1_lf) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "requested nixlf is greater than the max supported nix1_lf");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static const struct devlink_param rvu_af_dl_params[] = {
 	DEVLINK_PARAM_DRIVER(RVU_AF_DEVLINK_PARAM_ID_DWRR_MTU,
 			     "dwrr_mtu", DEVLINK_PARAM_TYPE_U32,
···
 			     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_NIX_MAXLF,
+			     "nix_maxlf", DEVLINK_PARAM_TYPE_U16,
+			     BIT(DEVLINK_PARAM_CMODE_RUNTIME),
+			     rvu_af_dl_nix_maxlf_get,
+			     rvu_af_dl_nix_maxlf_set,
+			     rvu_af_dl_nix_maxlf_validate),
 };
 
 /* Devlink switch mode */

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

···
 		npc_program_kpu_profile(rvu, blkaddr, idx, &rvu->kpu.kpu[idx]);
 }
 
-static int npc_mcam_rsrcs_init(struct rvu *rvu, int blkaddr)
+void npc_mcam_rsrcs_deinit(struct rvu *rvu)
+{
+	struct npc_mcam *mcam = &rvu->hw->mcam;
+
+	kfree(mcam->bmap);
+	kfree(mcam->bmap_reverse);
+	kfree(mcam->entry2pfvf_map);
+	kfree(mcam->cntr2pfvf_map);
+	kfree(mcam->entry2cntr_map);
+	kfree(mcam->cntr_refcnt);
+	kfree(mcam->entry2target_pffunc);
+	kfree(mcam->counters.bmap);
+}
+
+int npc_mcam_rsrcs_init(struct rvu *rvu, int blkaddr)
 {
 	int nixlf_count = rvu_get_nixlf_count(rvu);
 	struct npc_mcam *mcam = &rvu->hw->mcam;
···
 	mcam->pf_offset = mcam->nixlf_offset + nixlf_count;
 
 	/* Allocate bitmaps for managing MCAM entries */
-	mcam->bmap = devm_kcalloc(rvu->dev, BITS_TO_LONGS(mcam->bmap_entries),
-				  sizeof(long), GFP_KERNEL);
+	mcam->bmap = kmalloc_array(BITS_TO_LONGS(mcam->bmap_entries),
+				   sizeof(long), GFP_KERNEL);
 	if (!mcam->bmap)
 		return -ENOMEM;
 
-	mcam->bmap_reverse = devm_kcalloc(rvu->dev,
-					  BITS_TO_LONGS(mcam->bmap_entries),
-					  sizeof(long), GFP_KERNEL);
+	mcam->bmap_reverse = kmalloc_array(BITS_TO_LONGS(mcam->bmap_entries),
+					   sizeof(long), GFP_KERNEL);
 	if (!mcam->bmap_reverse)
-		return -ENOMEM;
+		goto free_bmap;
 
 	mcam->bmap_fcnt = mcam->bmap_entries;
 
 	/* Alloc memory for saving entry to RVU PFFUNC allocation mapping */
-	mcam->entry2pfvf_map = devm_kcalloc(rvu->dev, mcam->bmap_entries,
-					    sizeof(u16), GFP_KERNEL);
+	mcam->entry2pfvf_map = kmalloc_array(mcam->bmap_entries,
+					     sizeof(u16), GFP_KERNEL);
 	if (!mcam->entry2pfvf_map)
-		return -ENOMEM;
+		goto free_bmap_reverse;
 
 	/* Reserve 1/8th of MCAM entries at the bottom for low priority
 	 * allocations and another 1/8th at the top for high priority
···
 	 */
 	err = rvu_alloc_bitmap(&mcam->counters);
 	if (err)
-		return err;
+		goto free_entry_map;
 
-	mcam->cntr2pfvf_map = devm_kcalloc(rvu->dev, mcam->counters.max,
-					   sizeof(u16), GFP_KERNEL);
+	mcam->cntr2pfvf_map = kmalloc_array(mcam->counters.max,
+					    sizeof(u16), GFP_KERNEL);
 	if (!mcam->cntr2pfvf_map)
-		goto free_mem;
+		goto free_cntr_bmap;
 
 	/* Alloc memory for MCAM entry to counter mapping and for tracking
 	 * counter's reference count.
 	 */
-	mcam->entry2cntr_map = devm_kcalloc(rvu->dev, mcam->bmap_entries,
-					    sizeof(u16), GFP_KERNEL);
+	mcam->entry2cntr_map = kmalloc_array(mcam->bmap_entries,
+					     sizeof(u16), GFP_KERNEL);
 	if (!mcam->entry2cntr_map)
-		goto free_mem;
+		goto free_cntr_map;
 
-	mcam->cntr_refcnt = devm_kcalloc(rvu->dev, mcam->counters.max,
-					 sizeof(u16), GFP_KERNEL);
+	mcam->cntr_refcnt = kmalloc_array(mcam->counters.max,
+					  sizeof(u16), GFP_KERNEL);
 	if (!mcam->cntr_refcnt)
-		goto free_mem;
+		goto free_entry_cntr_map;
 
 	/* Alloc memory for saving target device of mcam rule */
-	mcam->entry2target_pffunc = devm_kcalloc(rvu->dev, mcam->total_entries,
-						 sizeof(u16), GFP_KERNEL);
+	mcam->entry2target_pffunc = kmalloc_array(mcam->total_entries,
+						  sizeof(u16), GFP_KERNEL);
 	if (!mcam->entry2target_pffunc)
-		goto free_mem;
+		goto free_cntr_refcnt;
 
 	for (index = 0; index < mcam->bmap_entries; index++) {
 		mcam->entry2pfvf_map[index] = NPC_MCAM_INVALID_MAP;
···
 
 	return 0;
 
-free_mem:
+free_cntr_refcnt:
+	kfree(mcam->cntr_refcnt);
+free_entry_cntr_map:
+	kfree(mcam->entry2cntr_map);
+free_cntr_map:
+	kfree(mcam->cntr2pfvf_map);
+free_cntr_bmap:
 	kfree(mcam->counters.bmap);
+free_entry_map:
+	kfree(mcam->entry2pfvf_map);
+free_bmap_reverse:
+	kfree(mcam->bmap_reverse);
+free_bmap:
+	kfree(mcam->counters.bmap);
+
 	return -ENOMEM;
 }
 
···
 	struct npc_mcam *mcam = &rvu->hw->mcam;
 
 	kfree(pkind->rsrc.bmap);
+	npc_mcam_rsrcs_deinit(rvu);
 	kfree(mcam->counters.bmap);
 	if (rvu->kpu_prfl_addr)
 		iounmap(rvu->kpu_prfl_addr);