scsi: lpfc: Add NVMe sequence level error recovery support

FC-NVMe-2 added support for sequence level error recovery in the FC-NVME
protocol. This allows for the detection of errors and lost frames and
immediate retransmission of data to avoid exchange termination, which
escalates into NVMeoFC connection and association failures. A significant
RAS improvement.

The driver is modified to indicate support for SLER in the NVMe PRLI is
issues and to check for support in the PRLI response.  When both sides
support it, the driver will set a bit in the WQE to enable the recovery
behavior on the exchange. The adapter will take care of all detection and
retransmission.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/lpfc/lpfc.h

@@ -797,6 +797,7 @@ struct lpfc_hba {
 	uint8_t  mds_diags_support;
 	uint8_t  bbcredit_support;
 	uint8_t  enab_exp_wqcq_pages;
+	u8	 nsler; /* Firmware supports FC-NVMe-2 SLER */
 
 	/* HBA Config Parameters */
 	uint32_t cfg_ack0;

drivers/scsi/lpfc/lpfc_disc.h

@@ -112,6 +112,8 @@ struct lpfc_nodelist {
 	uint8_t         nlp_retry;		/* used for ELS retries */
 	uint8_t         nlp_fcp_info;	        /* class info, bits 0-3 */
 #define NLP_FCP_2_DEVICE   0x10			/* FCP-2 device */
+	u8		nlp_nvme_info;	        /* NVME NSLER Support */
+#define NLP_NVME_NSLER     0x1			/* NVME NSLER device */
 
 	uint16_t        nlp_usg_map;	/* ndlp management usage bitmap */
 #define NLP_USG_NODE_ACT_BIT	0x1	/* Indicate ndlp is actively used */

drivers/scsi/lpfc/lpfc_els.c

@@ -2435,6 +2435,10 @@ lpfc_issue_els_prli(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
 		npr_nvme = (struct lpfc_nvme_prli *)pcmd;
 		bf_set(prli_type_code, npr_nvme, PRLI_NVME_TYPE);
 		bf_set(prli_estabImagePair, npr_nvme, 0);  /* Should be 0 */
+		if (phba->nsler) {
+			bf_set(prli_nsler, npr_nvme, 1);
+			bf_set(prli_conf, npr_nvme, 1);
+		}
 
 		/* Only initiators request first burst. */
 		if ((phba->cfg_nvme_enable_fb) &&

drivers/scsi/lpfc/lpfc_hw4.h

@@ -3480,6 +3480,10 @@ struct lpfc_sli4_parameters {
 #define cfg_bv1s_MASK                           0x00000001
 #define cfg_bv1s_WORD                           word19
 
+#define cfg_nsler_SHIFT                         12
+#define cfg_nsler_MASK                          0x00000001
+#define cfg_nsler_WORD                          word19
+
 	uint32_t word20;
 #define cfg_max_tow_xri_SHIFT			0
 #define cfg_max_tow_xri_MASK			0x0000ffff
@@ -4621,6 +4625,7 @@ struct lpfc_nvme_prli {
 #define prli_type_code_WORD             word1
 	uint32_t word_rsvd2;
 	uint32_t word_rsvd3;
+
 	uint32_t word4;
 #define prli_fba_SHIFT                  0
 #define prli_fba_MASK                   0x00000001
@@ -4637,6 +4642,9 @@ struct lpfc_nvme_prli {
 #define prli_conf_SHIFT                 7
 #define prli_conf_MASK                  0x00000001
 #define prli_conf_WORD                  word4
+#define prli_nsler_SHIFT		8
+#define prli_nsler_MASK			0x00000001
+#define prli_nsler_WORD			word4
 	uint32_t word5;
 #define prli_fb_sz_SHIFT                0
 #define prli_fb_sz_MASK                 0x0000ffff

drivers/scsi/lpfc/lpfc_init.c

@@ -11846,6 +11846,14 @@ lpfc_get_sli4_parameters(struct lpfc_hba *phba, LPFC_MBOXQ_t *mboxq)
 	else
 		phba->mds_diags_support = 0;
 
+	/*
+	 * Check if the SLI port supports NSLER
+	 */
+	if (bf_get(cfg_nsler, mbx_sli4_parameters))
+		phba->nsler = 1;
+	else
+		phba->nsler = 0;
+
 	return 0;
 }
 

drivers/scsi/lpfc/lpfc_nportdisc.c

@@ -799,9 +799,15 @@ lpfc_rcv_prli(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
 			if (npr->writeXferRdyDis)
 				ndlp->nlp_flag |= NLP_FIRSTBURST;
 		}
-		if (npr->Retry)
+		if (npr->Retry && ndlp->nlp_type &
+					(NLP_FCP_INITIATOR | NLP_FCP_TARGET))
 			ndlp->nlp_fcp_info |= NLP_FCP_2_DEVICE;
 
+		if (npr->Retry && phba->nsler &&
+		    ndlp->nlp_type & (NLP_NVME_INITIATOR | NLP_NVME_TARGET))
+			ndlp->nlp_nvme_info |= NLP_NVME_NSLER;
+
+
 		/* If this driver is in nvme target mode, set the ndlp's fc4
 		 * type to NVME provided the PRLI response claims NVME FC4
 		 * type.  Target mode does not issue gft_id so doesn't get
@@ -2024,6 +2030,11 @@ lpfc_cmpl_prli_prli_issue(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
 		if (bf_get_be32(prli_init, nvpr))
 			ndlp->nlp_type |= NLP_NVME_INITIATOR;
 
+		if (phba->nsler && bf_get_be32(prli_nsler, nvpr))
+			ndlp->nlp_nvme_info |= NLP_NVME_NSLER;
+		else
+			ndlp->nlp_nvme_info &= ~NLP_NVME_NSLER;
+
 		/* Target driver cannot solicit NVME FB. */
 		if (bf_get_be32(prli_tgt, nvpr)) {
 			/* Complete the nvme target roles.  The transport

drivers/scsi/lpfc/lpfc_nvme.c

@@ -1255,6 +1255,9 @@ lpfc_nvme_prep_io_cmd(struct lpfc_vport *vport,
 		       sizeof(uint32_t) * 8);
 		cstat->control_requests++;
 	}
+
+	if (pnode->nlp_nvme_info & NLP_NVME_NSLER)
+		bf_set(wqe_erp, &wqe->generic.wqe_com, 1);
 	/*
 	 * Finish initializing those WQE fields that are independent
 	 * of the nvme_cmnd request_buffer