octeontx2-af: Add new mbox messages to retrieve MCAM entries

This patch introduces new mailbox mesages to retrieve a given
MCAM entry or base flow steering rule of a VF installed by its
parent PF. This helps while updating the existing MCAM rules
with out re-framing the whole mailbox request again. The INSTALL
FLOW mailbox consumer can read-modify-write the existing entry.
Similarly while installing new flow rules for a VF, the base
flow steering rule match creteria is copied to the new flow rule
and the deltas are appended to the new rule.

Signed-off-by: Naveen Mamindlapalli <naveenm@marvell.com>
Co-developed-by: Vamsi Attunuru <vattunuru@marvell.com>
Signed-off-by: Vamsi Attunuru <vattunuru@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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

@@ -192,6 +192,11 @@ M(NPC_INSTALL_FLOW,	  0x600d, npc_install_flow,			       \
 				  npc_install_flow_req, npc_install_flow_rsp)  \
 M(NPC_DELETE_FLOW,	  0x600e, npc_delete_flow,			\
 				  npc_delete_flow_req, msg_rsp)		\
+M(NPC_MCAM_READ_ENTRY,	  0x600f, npc_mcam_read_entry,			\
+				  npc_mcam_read_entry_req,		\
+				  npc_mcam_read_entry_rsp)		\
+M(NPC_MCAM_READ_BASE_RULE, 0x6011, npc_read_base_steer_rule,            \
+				   msg_req, npc_mcam_read_base_rule_rsp)  \
 /* NIX mbox IDs (range 0x8000 - 0xFFFF) */				\
 M(NIX_LF_ALLOC,		0x8000, nix_lf_alloc,				\
 				 nix_lf_alloc_req, nix_lf_alloc_rsp)	\
@@ -1009,6 +1014,23 @@ struct npc_delete_flow_req {
 	u8 all; /* PF + VFs */
 };
 
+struct npc_mcam_read_entry_req {
+	struct mbox_msghdr hdr;
+	u16 entry;	 /* MCAM entry to read */
+};
+
+struct npc_mcam_read_entry_rsp {
+	struct mbox_msghdr hdr;
+	struct mcam_entry entry_data;
+	u8 intf;
+	u8 enable;
+};
+
+struct npc_mcam_read_base_rule_rsp {
+	struct mbox_msghdr hdr;
+	struct mcam_entry entry;
+};
+
 enum ptp_op {
 	PTP_OP_ADJFINE = 0,
 	PTP_OP_GET_CLOCK = 1,

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

@@ -2193,6 +2193,30 @@ int rvu_mbox_handler_npc_mcam_free_entry(struct rvu *rvu,
 	return rc;
 }
 
+int rvu_mbox_handler_npc_mcam_read_entry(struct rvu *rvu,
+					 struct npc_mcam_read_entry_req *req,
+					 struct npc_mcam_read_entry_rsp *rsp)
+{
+	struct npc_mcam *mcam = &rvu->hw->mcam;
+	u16 pcifunc = req->hdr.pcifunc;
+	int blkaddr, rc;
+
+	blkaddr = rvu_get_blkaddr(rvu, BLKTYPE_NPC, 0);
+	if (blkaddr < 0)
+		return NPC_MCAM_INVALID_REQ;
+
+	mutex_lock(&mcam->lock);
+	rc = npc_mcam_verify_entry(mcam, pcifunc, req->entry);
+	if (!rc) {
+		npc_read_mcam_entry(rvu, mcam, blkaddr, req->entry,
+				    &rsp->entry_data,
+				    &rsp->intf, &rsp->enable);
+	}
+
+	mutex_unlock(&mcam->lock);
+	return rc;
+}
+
 int rvu_mbox_handler_npc_mcam_write_entry(struct rvu *rvu,
 					  struct npc_mcam_write_entry_req *req,
 					  struct msg_rsp *rsp)
@@ -2753,3 +2777,49 @@ bool rvu_npc_write_default_rule(struct rvu *rvu, int blkaddr, int nixlf,
 
 	return enable;
 }
+
+int rvu_mbox_handler_npc_read_base_steer_rule(struct rvu *rvu,
+					      struct msg_req *req,
+					      struct npc_mcam_read_base_rule_rsp *rsp)
+{
+	struct npc_mcam *mcam = &rvu->hw->mcam;
+	int index, blkaddr, nixlf, rc = 0;
+	u16 pcifunc = req->hdr.pcifunc;
+	struct rvu_pfvf *pfvf;
+	u8 intf, enable;
+
+	blkaddr = rvu_get_blkaddr(rvu, BLKTYPE_NPC, 0);
+	if (blkaddr < 0)
+		return NPC_MCAM_INVALID_REQ;
+
+	/* Return the channel number in case of PF */
+	if (!(pcifunc & RVU_PFVF_FUNC_MASK)) {
+		pfvf = rvu_get_pfvf(rvu, pcifunc);
+		rsp->entry.kw[0] = pfvf->rx_chan_base;
+		rsp->entry.kw_mask[0] = 0xFFFULL;
+		goto out;
+	}
+
+	/* Find the pkt steering rule installed by PF to this VF */
+	mutex_lock(&mcam->lock);
+	for (index = 0; index < mcam->bmap_entries; index++) {
+		if (mcam->entry2target_pffunc[index] == pcifunc)
+			goto read_entry;
+	}
+
+	rc = nix_get_nixlf(rvu, pcifunc, &nixlf, NULL);
+	if (rc < 0) {
+		mutex_unlock(&mcam->lock);
+		goto out;
+	}
+	/* Read the default ucast entry if there is no pkt steering rule */
+	index = npc_get_nixlf_mcam_index(mcam, pcifunc, nixlf,
+					 NIXLF_UCAST_ENTRY);
+read_entry:
+	/* Read the mcam entry */
+	npc_read_mcam_entry(rvu, mcam, blkaddr, index, &rsp->entry, &intf,
+			    &enable);
+	mutex_unlock(&mcam->lock);
+out:
+	return rc;
+}